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  • 1.
    Hildebrand, Cisilia
    et al.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Hörtin, Stina
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    A comparative study between Emme and Visum with respect to public transport assignment2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Macroscopic traffic simulations are widely used in the world in order to provide assistance in the traffic infrastructure development as well as for the strategic traffic planning. When studying a large traffic network macroscopic traffic simulation can be used to model current and future traffic situations. The two most common software used for traffic simulation in Sweden today are Emme and Visum, developed by INRO respective PTV.

    The aim of the thesis is to perform a comparison between the software Emme and Visum with respect to the assignment of public transport, in other words how passengers choose their routes on the existing public transport lines. However, in order to make a complete software comparison the run-time, analysis capabilities, multi-modality, capacity to model various behavioural phenomena like crowding, fares etc. this will not be done in this comparison. It is of interest to study the differences between the two software algorithms and why they might occur because the Swedish Transport Administration uses Emme and the Traffic Administration in Stockholm uses Visum when planning public transport. The comparison will include the resulting volumes on transit lines, travel times, flow through specific nodes, number of boarding, auxiliary volumes and number of transits. The goal of this work is to answer the following objective: What are the differences with modelling a public transport network in Emme and in Visum, based on that the passengers only have information about the travel times and the line frequency, and why does the differences occur?

    In order to evaluate how the algorithms work in a larger network, Nacka municipality (in Stockholm) and the new metro route between Nacka Forum and Kungsträdgården have been used. The motivation for choosing this area and case is due to that it is interesting to see what differences could occur between the programs when there is a major change in the traffic network.

    The network of Nacka, and parts of Stockholm City, has been developed from an existing road network of Sweden and then restricted by "cutting out" the area of interest and then removing all public transportation lines outside the selected area. The OD-matrix was also limited and in order not to loose the correct flow of travellers portal zones was used to collect and retain volumes.

    To find out why the differences occur the headway-based algorithms in each software were studied carefully. An example of a small and simple network (consisting of only a start and end node) has been used to demonstrate and show how the algorithms work and why volumes split differently on the existing transit lines in Emme and Visum. The limited network of Nacka shows how the different software may produce different results in a larger public transport network.

    The results show that there are differences between the program algorithms but the significance varies depending on which output is being studied and the size of the network. The Visum algorithm results in more total boardings, i.e. more passengers have an optimal strategy including a transit. The algorithms are very similar in both software programs, since they include more or less parts of the optimal strategy. The parameters used are taken more or less into consideration in Emme and Visum. For example Visum will first of all focus on the shortest total travel time and then consider the other lines with respect to the maximum waiting time. Emme however, first focuses on the shortest travel time and then considers the total travel time for other lines with half the waiting time instead of the maximum wait time. This results in that less transit lines will be attractive in Emme compared to Visum. The thesis concludes that varying the parameters for public transport in each software algorithm one can obtain similar results, which implies that it is most important to choose the best parameter values and not to choose the "best" software when simulating a traffic network.

  • 2.
    Wallin, Ragnar
    et al.
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, The Institute of Technology.
    Kao, Chung-Yao
    University of Melbourne, Australia.
    Hansson, Anders
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, The Institute of Technology.
    A Cutting Plane Method for Solving KYP-SDPs2006Report (Other academic)
    Abstract [en]

    Semidefinite programs originating from the Kalman-Yakubovich-Popov lemma are convex optimization problems and there exist polynomial time algorithms that solve them. However, the number of variables is often very large making the computational time extremely long. Algorithms more efficient than general purpose solvers are thus needed. To this end structure exploiting algorithms have been proposed, based on the dual formulation. In this paper a cutting plane algorithm is proposed. In a comparison with a general purpose solver and a structure exploiting solver it is shown that the cutting plane based solver can handle optimization problems of much higher dimension.

  • 3.
    Wallin, Ragnar
    et al.
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, The Institute of Technology.
    Kao, Chung-Yao
    University of Melbourne, Australia.
    Hansson, Anders
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, The Institute of Technology.
    A Cutting Plane Method for Solving KYP-SDPs2008In: Automatica, ISSN 0005-1098, Vol. 44, no 2, 418-429 p.Article in journal (Refereed)
    Abstract [en]

    Semidefinite programs originating from the Kalman-Yakubovich-Popov lemma are convex optimization problems and there exist polynomial time algorithms that solve them. However, the number of variables is often very large making the computational time extremely long. Algorithms more efficient than general purpose solvers are thus needed. To this end structure exploiting algorithms have been proposed, based on the dual formulation. In this paper a cutting plane algorithm is proposed. In a comparison with a general purpose solver and a structure exploiting solver it is shown that the cutting plane based solver can handle optimization problems of much higher dimension.

  • 4.
    Holmberg, Kaj
    et al.
    Linköping University, Department of Mathematics. Linköping University, The Institute of Technology.
    Yuan, Di
    Linköping University, Department of Mathematics. Linköping University, The Institute of Technology.
    A Lagrangian heuristic based branch-and-bound approach for the capacitated network design problem2000In: Operations Research, ISSN 0030-364X, E-ISSN 1526-5463, Vol. 48, no 3, 461-481 p.Article in journal (Refereed)
    Abstract [en]

    The capacitated network design problem is a multicommodity minimal cost network flow problem with fixed charges on the arcs and is well known to be NP-hard. The problem type is very common in the context of transportation networks, telecommunication networks, etc. In this paper we propose an efficient method for this problem, based on a Lagrangian heuristic within a branch-and-bound framework. The Lagrangian heuristic uses a Lagrangian relaxation to obtain easily solved subproblems and solves the Lagrangian dual by subgradient optimization. It also includes techniques for finding primal feasible solutions. The Lagrangian heuristic is then embedded into a branch-and-bound scheme that yields further primal improvements. Special penalty tests and cutting criteria are developed. The branch-and-bound scheme can either be an exact method that guarantees the optimal solution of the problem or be a quicker heuristic. The method has been tested on networks of various structures and sizes. Computational comparisons between this method and a state-of-the-art mixed-integer code are presented. The method is found to be capable of generating good feasible solutions to large-scale problems within reasonable time and data storage limits.

  • 5.
    Lindén, Erik
    Linköping University, Department of Computer and Information Science, Software and Systems.
    A latency comparison of IoT protocols in MES2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Many industries are now moving several of their processes into the cloud computing sphere. One important process is to collect machine data in an effective way. Moving signal collection processes to the cloud instead of on premise raises many questions about performance, scalability, security and cost.This thesis focuses on some of the market leading and cutting edge protocols appropriate for industrial production data collection. It investigates and compares the pros and cons of the protocols with respect to the demands of industrial systems. The thesis also presents examples of how the protocols can be used to collect data all the way to a higher-level system such as ERP or MES.The protocols focused on are MQTT and AMQP (in OPC-UA). The possibilities of OPC-UA in cloud computing is of extra interest to investigate in this thesis due to its increasing usage and development.

  • 6.
    Tiwari, Ashutosh
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Biosensors and Bioelectronics. Linköping University, The Institute of Technology.
    Valyukh, SergiyLinköping University, Department of Physics, Chemistry and Biology, Applied Optics . Linköping University, The Institute of Technology.
    Advanced Energy Materials2014Collection (editor) (Other academic)
    Abstract [en]

    An essential resource for scientists designing new energy materials for the vast landscape of solar energy conversion as well as materials processing and characterizatio.

    Based on the new and fundamental research on novel energy materials with tailor-made photonic properties, the role of materials engineering has been to provide much needed support in the development of photovoltaic devices. Advanced Energy Materials offers a unique, state-of-the-art look at the new world of novel energy materials science, shedding light on the subject's vast multi-disciplinary approach.

    The book focuses particularly on photovoltaics, efficient light sources, fuel cells, energy-saving technologies, energy storage technologies, nanostructured materials as well as innovating materials and techniques for future nanoscale electronics. Pathways to future development are also discussed.Critical, cutting-edge subjects are addressed, including:

    • Non-imaging focusing heliostat; state-of-the-art of nanostructures
    • Metal oxide semiconductors and their nanocomposites
    • Superionic solids; polymer nanocomposites; solid electrolytes; advanced electronics
    • Electronic and optical properties of lead sulfide
    • High-electron mobility transistors and light-emitting diodes
    • Anti-ferroelectric liquid crystals; PEEK membrane for fuel cells
    • Advanced phosphors for energy-efficient lighting
    • Molecular computation photovoltaics and photocatalysts
    • Photovoltaic device technology and non-conventional energy applicationsReadership

    The book is written for a large and broad readership including researchers and university graduate students from diverse backgrounds such as chemistry, materials science, physics, and engineering working in the fields of nanotechnology, photovoltaic device technology, and non-conventional energy.

  • 7.
    Tiwari, Ashutosh
    Linköping University, Department of Physics, Chemistry and Biology, Biosensors and Bioelectronics. Linköping University, The Institute of Technology.
    Advanced Healthcare Materials2014Collection (editor) (Other academic)
    Abstract [en]

    Advanced materials are attracting strong interest in the fundamental as well as applied sciences and are being extensively explored for their potential usage in a range of healthcare technological and biological applications.Advanced Healthcare Nanomaterials summarises the current status of knowledge in the fields of advanced materials for functional therapeutics, point-of-care diagnostics, translational materials, up and coming bio-engineering devices. The book highlights the key features which enable engineers to design stimuli-responsive smart nanoparticles, novel biomaterials, nano/micro-devices for diagnosis, therapy (theranostics).The leading contributor researchers cover the following topics: 

    • State-of-the-art of biomaterials for human health
    • Micro- and nanoparticles and their application in biosensors
    • The role of immunoassays
    • Stimuli-responsive smart nanoparticles
    • Diagnosis and treatment of cancer
    • Advanced materials for biomedical application and drug delivery
    • Nanoparticles for diagnosis and/or treatment of Alzheimers disease
    • Hierarchical modelling of elastic behavior of human dental tissue
    • Biodegradable porous hydrogels
    • Hydrogels in tissue engineering, drug delivery and wound care
    • Modified natural zeolites
    • Supramolecular hydrogels based on cyclodextrin poly(pseudo)rotaxane
    • Polyhydroxyalkanoate-based biomaterials
    • Biomimetic molecularly imprinted polymers

    The book is written for readers from diverse backgrounds across chemistry, physics, materials science and engineering, medical science, pharmacy, biotechnology, and biomedical engineering. It offers a comprehensive view of cutting-edge research on advanced materials for healthcare technology and applications.

  • 8.
    Tiwari, Ashutosh
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Biosensors and Bioelectronics. Linköping University, The Institute of Technology.
    Demir, Mustafa M.Izmir Institute of Technology, Turkey.
    Advanced Sensor and Detection Materials2014Collection (editor) (Other academic)
    Abstract [en]

    The development of sensors at macroscopic or nanometric scales in solid, liquid, or gas phases, contact or noncontact configurations, has driven the research of sensor & detection materials and technology into high gear. The emphasis on detection techniques requires the use of spin crossover organic, inorganic and composite materials and methods that could be unique for sensors fabrication.  The influence of length, composition and conformation structure of materials on their properties and the possibilities to adjust sensing properties by doping or adding the side-groups are the starting point of multifarious sensing. The role of inter-molecular interactions, polymer and ordered phases formation, as well as the behavior under pressure, magnetic and electric fields are also important facts for processing of ultra-sensing materials. Advanced Sensor and Detection Materials highlights the key features that aid the design of new sensor and detection materials for a multitude of sensor and detection devices. The senior contributors write on the follow topics:

    • Construction of nanostructures
    • The role of the shape in the design of new nanoparticles
    • Advances in sensors’ nanotechnology
    • Molecularly imprinted polymer for enantioselective sensing devices
    • Ferrites for high frequency applications
    • Mesoporous Silica: Making “Sense” of Sensors
    • Porous TiO2-Au/Ag materials
    • Ferroelectronic glass-ceramics
    • NASICON: Synthesis, structure and electrical characterisation
    • Heavy clay products quality
    • Ionic liquids
    • Dendrimers and hyperbranched polymers
    • Theoretical investigation of superconducting state parameters
    • Microscopic polarization and thermal conductivity of binary Wurtzite nitrides
    • Experiments techniques and theoretical background to study materials

    The book is written for readers from diverse backgrounds across chemistry, physics, materials science and engineering, medical science, pharmacy, biotechnology, and biomedical engineering. It offers a comprehensive view of cutting-edge research on advanced materials for sensor and detection technology and applications.

  • 9.
    Kihlman, Henrik
    Linköping University, Department of Mechanical Engineering. Linköping University, The Institute of Technology.
    Affordable automation for airframe assembly: developing of key enabling technologies2005Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Building aircraft is a challenging field. An aircraft has a life expectancy of 40 years, compared to just 10 years for a car. Given the vibrations of flying at close to Mach one at an altitude of 10,000 meters, these machines must function flawlessly in a tough environment. This demands high quality in the assembly processes. The typical part joining process in the automotive industry is welding, whereas in the aircraft industry, assembly is made through drilling, followed by fastening. The typical tolerances for part location in aircraft assembly, as well as for hole drilling, is +/- 0.2 mm.

    This dissertation discusses the use of industrial robots, widely used for welding and pick-and-place operation for automotive industry, in the automation of the aircraft industry, and specifically for the drilling of holes in the assembly process of airframe parts. The dissertation presents how a new drilling technology called orbital drilling is incorporated with and industrial robot. Orbital drilling reduces the cutting forces up to ten times compared to conventional drilling using a spiral cutter.

    The robot is also utilized for performing changeovers between different airframe structure types. A novel jointed reconfigurable tooling system called Affordable Reconfigurable Tooling (ART) is presented, which uses the robot to reconfigure flexible fixture modules. The ART system can also be rebuilt, which means that the tool is dismantled and reused for a completely different product family (e.g. wings, fins or fuselage sections). This is made possible through a modular framework, i.e. not welded as with conventional tooling, but rather jointed by screws.

    Robots, originally developed for the automotive industry, have an accuracy which is ten times less accurate than that required for aerospace applications. To help meet this limitation in the use of robots in aircraft assembly, an additional metrology system, used in the aircraft industry for calibrating assembly tooling, is integrated into the robot controller. The feedback loop enables the robot to be positioned to ±0.05 mm absolute accuracy. This integration is made possible by existing embedded software packages for the robot and the metrology system.

    The processes in the system are programmed in a software package with an intuitive user interface in a 3D-environment, normally used for the offline-programming of robots in automotive industry. The planning is intuitive, and an approach towards a process planning abstraction level is presented where processes are defined directly on the coordinate frames constituting the robot trajectories and manual operations. Tolerance on accuracy requirements are dynamically programmed in the same environment. The metrology system, working online with the robot controller, eliminates most of the calibration work required in traditional robot programming. Changes in the operation planning take less than a minute to run physically with the best tolerance.

    List of papers
    1. Reconfigurable tooling for airframe assembly: a state-of-the-art review of the related literature and a short presentation of a new tooling concept
    Open this publication in new window or tab >>Reconfigurable tooling for airframe assembly: a state-of-the-art review of the related literature and a short presentation of a new tooling concept
    2001 (English)Conference paper, Published paper (Refereed)
    Abstract [en]

    From the early days of aircraft manufacturing Dedicated Tooling has been used in the assembly process to ensure the attainment of assembly tolerances and product quality. Dedicated Tooling clamps the aircraft parts to be assembled into the jig to enable assembly by riveting. However, increased competition in the aircraft industry has driven the need to improve quality while reducing cost and in turn the need for innovative solutions to accomplish this.

    In this review paper the possibility of using metrology to increase the position accuracy in robotics will be examined. This is necessary to be able to use robotics in assembly of aircraft parts with the appropriate accuracy. Also, because of the small product volumes in the aircraft industry, the jigs must be flexible in order to assemble more than one structure in each jig. Solving these two problems could be the break through for starting to use robotics in aircraft assembly at a higher rate, and doing so in a cost-effective way.

    By then reviewing literature of today's flexible tooling technology in the aircraft industry, the conclusion indicates that there is a gap to fill in aircraft assembly tooling. Modular Tools is one solution where standard aluminium profiles are used to manufacture jigs with some degree of flexibility. Another way is pogo fixturing, which uses sticks to hold airframe parts together in the assembly process. The sticks can only be reconfigured in a limited range, and are not cost-effective. By using Affordable Reconfigurable Tooling, the jigs will not only have greater ability to be reconfigured, but by using robotics for the reconfiguration task as well as for drilling, riveting and other material handling tasks, the system will also be cost effective.

    Place, publisher, year, edition, pages
    Ann Arbor, Michigan, USA: University of Michigan, 2001
    Keyword
    Reconfigurable, Airframe, Assembly, Tooling, Flexibility, Affordable
    National Category
    Production Engineering, Human Work Science and Ergonomics
    Identifiers
    urn:nbn:se:liu:diva-73297 (URN)
    Conference
    CIRP 1st International Conference on Agile, Reconfigurable Manufacturing, Ann Arbor, Michigan, USA, 21-22 May
    Available from: 2012-01-13 Created: 2012-01-02 Last updated: 2012-11-29Bibliographically approved
    2. Reconfigurable aircraft assembly: using industrial robots and new tooling to meet future production scenarios
    Open this publication in new window or tab >>Reconfigurable aircraft assembly: using industrial robots and new tooling to meet future production scenarios
    2002 (English)In: Proceedings of the 33rd ISR (International Symposium on Robotics), 2002Conference paper, Published paper (Refereed)
    Abstract [en]

    This paper presents the development of a new concept for aircraft airframe assembly tooling. While conventional aircraft assembly tooling relics on rigid steel frames this novel approach can be re-con figured for different products by the help of an accurate laser tracker guided industrial robot. Through this, aircraft manufacturers can better cope with an increased number of variants and smaller volumes which will increase the already high tooling costs. So far in the project a tooling concept has been conceptually designed and economically evaluated. The early technical results of the concepntal work indicate that the concept will work provided that enough mechanical stiffness can be obtained. The economical analysis shows that despite a much higher investment cost, a reconfigurable tool can be economical if it will replace 4-5 conventional tools. In certain future production scenarios reconfigurable tooling can play a very important role to keep the tooling costs down.

    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-85838 (URN)
    Conference
    33rd International Symposium on Robotics in Stockholm, October 8-10
    Available from: 2012-11-29 Created: 2012-11-29 Last updated: 2012-11-29
    3. Affordable reconfigurable tooling
    Open this publication in new window or tab >>Affordable reconfigurable tooling
    2002 (English)Conference paper, Published paper (Refereed)
    Abstract [en]

    Since the early days of aircraft assembly, welded steel structures called Conventional Tooling has been used for positioning and holding parts in place during assembly. This paper presents a new tooling concept called Affordable Reconfigurable Tooling, where a robot is not only used for drilling and riveting but also for reconfiguring the tool itself. The concept consists of modular units that can either be reconfigured between products of the same family of assembly or rebuilt between product families. The research is part of an ongoing EU-founded aircraft industry project - ADFAST*.

    Place, publisher, year, edition, pages
    Society of Automotive Engineers, 2002
    National Category
    Aerospace Engineering
    Identifiers
    urn:nbn:se:liu:diva-73299 (URN)10.4271/2002-01-2645 (DOI)0-7680-1285-6 (ISBN)
    Conference
    2002 SAE Automated Fastening Conference & Exhibition, 1 October 2002, Chester, United Kingdom
    Projects
    ADFAST
    Available from: 2012-01-13 Created: 2012-01-02 Last updated: 2012-11-29Bibliographically approved
    4. Robotic orbital drilling of structures for aerospace applications
    Open this publication in new window or tab >>Robotic orbital drilling of structures for aerospace applications
    2002 (English)Conference paper, Published paper (Refereed)
    Abstract [en]

    This paper describes ongoing research into orbital drilling using standard industrial robots. The research is a part of an ongoing EU funded aircraft industry project - ADFAST*. Generally it is difficult to use standard industrial robots to automate drilling in the aerospace industry. The stiffness of the standard robotic device is not sufficient to resist the deflections caused by the cutting forces from the drilling process, therefore it is difficult to achieve the tight hole tolerance requirements. Orbital drilling creates lower axial cutting forces compared to conventional drilling and therefore allows the use of low-cost standard industrial robots for drilling holes within the required hole tolerances. This paper presents results from a study where forces, moments and dislocations produced during orbital- and conventional drilling have been measured.

    Place, publisher, year, edition, pages
    Chester, United Kingdom: Society of Automotive Engineers, 2002
    National Category
    Production Engineering, Human Work Science and Ergonomics
    Identifiers
    urn:nbn:se:liu:diva-73377 (URN)10.4271/2002-01-2636 (DOI)
    Conference
    SAE Automated Fastening Conference & Exhibition, Oktober 1, 2002, Chester, United Kingdom
    Available from: 2012-01-13 Created: 2012-01-02 Last updated: 2012-11-29Bibliographically approved
    5. 6DOF metrology-integrated robot control
    Open this publication in new window or tab >>6DOF metrology-integrated robot control
    2003 (English)Conference paper, Published paper (Refereed)
    Abstract [en]

    This paper describes ongoing research into Metrology-integrated robot control. The research is a part of an ongoing EU funded aircraft industry project – ADFAST*. The ADFAST project tries to implement the use of industrial robots in low-volume production, high-demand-on-accuracy operations and for dynamic force compensation. To detect and compensate deflection in industrial robots during a process, the robot uses a metrology system. The metrology system supervises the tool center point of the robot as it executes its processes. Leica has recently released a new metrology system; the LTD800, which measures distances with laser interferometry and can simultaneously measure orientation of targets, through photogrammetry, using an additional camera on top of the measuring unit. This paper will describe theory and results from tests performed on integrating the LTD800 with the robot.

    Place, publisher, year, edition, pages
    Montreal, QC, Canada: Society of Automotive Engineers, 2003
    Keyword
    Aircraft Assembly
    National Category
    Production Engineering, Human Work Science and Ergonomics Aerospace Engineering
    Identifiers
    urn:nbn:se:liu:diva-73378 (URN)10.4271/2003-01-2961 (DOI)
    Conference
    Automated Fastening Conference & Exposition, September 8, 2003, Montreal, Canada
    Available from: 2012-01-13 Created: 2012-01-02 Last updated: 2012-11-29Bibliographically approved
    6. Metrology-integrated industrial robots: calibration, implementation and testing
    Open this publication in new window or tab >>Metrology-integrated industrial robots: calibration, implementation and testing
    Show others...
    2004 (English)In: Proceedings of the 35th ISR (International Symposium on Robotics), 2004Conference paper, Published paper (Other academic)
    Abstract [en]

    This paper presents integration of a metrology system and an industrial robot. The metrology system consists of a laser tracker that measures the distance to a prism with high accuracy and a camera that through photogrammetry measures the orientation of a reflector. Both laser prism and camera reflector is integrated to a 6D-Reflector that is attached close to the TCP of an industrial robot. Tracker and robot is connected to a PC on a TCP/IP network. The PC takes measurements with the tracker, and thereby compensates the robot to reach high absolute accuracy in the robot positioning (+/-50 μm). The 6D-Reflector has multi-functionality and simplifies calibration procedures. This paper explains the architecture of the system and the methods for calibration.

    Keyword
    Metrology, laser, photogrammetry, robot, online control, calibration
    National Category
    Production Engineering, Human Work Science and Ergonomics
    Identifiers
    urn:nbn:se:liu:diva-73380 (URN)
    Conference
    35th ISR International Symposium on Robotics, 23-26 March, Paris, France
    Available from: 2012-01-09 Created: 2012-01-02 Last updated: 2012-11-29Bibliographically approved
    7. Low-cost automation for aircraft assembly
    Open this publication in new window or tab >>Low-cost automation for aircraft assembly
    2004 (English)Conference paper, Published paper (Refereed)
    Abstract [en]

    In this paper solution for low-cost automation of aircraft assembly is presented. The concept of this development is closely related to "Lean Automation", which in this case concerns the use of modern standard equipment such as standard robots, PC-computers and a newlydeveloped spatial sensor system for prec1s1on measurements of positions. The robot is used to perform reconfiguration of tooling modules that arepossible to be configured/reconfigured in six degrees of freedom. A prototype developed as the result of an EU-project called ADFAST* has been evaluated at Linköping University in Sweden. Technical functionality is reported where the robot manages to configure the flexible tooling modules to a total error bellow 50 μm. This paper presents the resu~s on the portion of the project addressing robot, metrology system and tooling.

    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-22547 (URN)10.4271/2004-01-2830 (DOI)1810 (Local ID)1810 (Archive number)1810 (OAI)
    Conference
    SAE 2004 Aerospace Manufacturing & Automated Fastening Conference & Exhibition, September 21th 2004, St Louis, Missouri, United States
    Available from: 2009-10-07 Created: 2009-10-07 Last updated: 2012-11-29
    8. Orbital drilling: implementation and evaluation
    Open this publication in new window or tab >>Orbital drilling: implementation and evaluation
    2004 (English)Conference paper, Published paper (Refereed)
    Abstract [en]

    This paper deals with issues about Orbital drilling implementation and evaluation. The paper summarizes and includes the so far written papers about Orbital drilling.

    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-22549 (URN)10.4271/2004-01-2814 (DOI)1812 (Local ID)1812 (Archive number)1812 (OAI)
    Conference
    SAE 2004 Aerospace Manufacturing & Automated Fastening Conference & Exhibition, September 21th 2004, St Louis, Missouri, United States
    Available from: 2009-10-07 Created: 2009-10-07 Last updated: 2012-11-29
  • 10.
    Wallin, Erik
    Linköping University, Department of Physics, Chemistry and Biology, Plasma and Coating Physics . Linköping University, The Institute of Technology.
    Alumina Thin Films: From Computer Calculations to Cutting Tools2008Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The work presented in this thesis deals with experimental and theoretical studies related to alumina thin films. Alumina, Al2O3, is a polymorphic material utilized in a variety of applications, e.g., in the form of thin films. However, controlling thin film growth of this material, in particular at low substrate temperatures, is not straightforward. The aim of this work is to increase the understanding of the basic mechanisms governing alumina growth and to investigate novel ways of synthesizing alumina coatings. The thesis can be divided into two main parts, where the first part deals with fundamental studies of mechanisms affecting alumina growth and the second part with more application-oriented studies of high power impulse magnetron sputter (HiPIMS) deposition of the material.

    In the first part, it was shown that the thermodynamically stable α phase, which normally is synthesized at substrate temperatures of around 1000 °C, can be grown using reactive sputtering at a substrate temperature of merely 500 °C by controlling the nucleation surface. This was done by predepositing a Cr2O3 nucleation layer. Moreover, it was found that an additional requirement for the formation of the α phase is that the depositions are carried out at low enough total pressure and high enough oxygen partial pressure. Based on these observations, it was concluded that energetic bombardment, plausibly originating from energetic oxygen, is necessary for the formation of α-alumina (in addition to the effect of the chromia nucleation layer). Moreover, the effects of residual water on the growth of crystalline films were investigated by varying the partial pressure of water in the ultra high vacuum (UHV) chamber. Films deposited onto chromia nucleation layers exhibited a columnar structure and consisted of crystalline α-alumina if deposited under UHV conditions. However, as water to a partial pressure of 1*10-5 Torr was introduced, the columnar α-alumina growth was disrupted. Instead, a microstructure consisting of small, equiaxed grains was formed, and the γ-alumina content was found to increase with increasing film thickness.

    To gain a better understanding of the atomistic processes occurring on the surface, density functional theory based computational studies of adsorption and diffusion of Al, O, AlO, and O2 on different α-alumina (0001) surfaces were also performed. The results give possible reasons for the difficulties in growing the α phase at low temperatures through the identification of several metastable adsorption sites and also show how adsorbed hydrogen might inhibit further growth of α-alumina crystallites. In addition, it was shown that the Al surface diffusion activation energies are unexpectedly low, suggesting that limited surface diffusivity is not the main obstacle for low-temperature α-alumina growth. Instead, it is suggested to be more important to find ways of reducing the amount of impurities, especially hydrogen, in the process and to facilitate α-alumina nucleation when designing new processes for low-temperature deposition of α-alumina.

    In the second part of the thesis, reactive HiPIMS deposition of alumina was studied. In HiPIMS, a high-density plasma is created by applying very high power to the sputtering magnetron at a low duty cycle. It was found, both from experiments and modeling, that the use of HiPIMS drastically influences the characteristics of the reactive sputtering process, causing reduced target poisoning and thereby reduced or eliminated hysteresis effects and relatively high deposition rates of stoichiometric alumina films. This is not only of importance for alumina growth, but for reactive sputter deposition in general, where hysteresis effects and loss of deposition rate pose a substantial problem. Moreover, it was found that the energetic and ionized deposition flux in the HiPIMS discharge can be used to lower the deposition temperature of α-alumina. Coatings predominantly consisting of the α phase were grown at temperatures as low as 650 °C directly onto cemented carbide substrates without the use of nucleation layers. Such coatings were also deposited onto cutting inserts and were tested in a steel turning application. The coatings were found to increase the crater wear resistance compared to a benchmark TiAlN coating, and the process consequently shows great potential for further development towards industrial applications.

    List of papers
    1. Phase control of Al2O3 thin films grown at low temperatures
    Open this publication in new window or tab >>Phase control of Al2O3 thin films grown at low temperatures
    Show others...
    2006 (English)In: Thin Solid Films, ISSN 0040-6090, Vol. 513, no 1-2, 57-59 p.Article in journal (Refereed) Published
    Abstract [en]

    Low-temperature growth (500 °C) of α-Al2O3 thin films by reactive magnetron sputtering was achieved for the first time. The films were grown onto Cr2O3 nucleation layers and the effects of the total and O2 partial pressures were investigated. At 0.33 Pa total pressure and ≥ 16 mPa O2 partial pressure α-Al2O3 films formed, while at lower O2 pressure or higher total pressure (0.67 Pa), only γ phase was detected in the films (which were all stoichiometric). Based on these results we suggest that α phase formation was promoted by a high energetic bombardment of the growth surface. This implies that the phase content of Al2O3 films can be controlled by controlling the energy of the depositing species. The effect of residual H2O (10− 4 Pa) on the films was also studied, showing no change in phase content and no incorporated H (< 0.1%). Overall, these results are of fundamental importance in the further development of low-temperature Al2O3 growth processes.

    Place, publisher, year, edition, pages
    Elsevier, 2006
    Keyword
    Aluminum oxide, Chromium oxide, Sputtering, Ion bombardment, X-ray diffraction
    National Category
    Physical Sciences
    Identifiers
    urn:nbn:se:liu:diva-14318 (URN)10.1016/j.tsf.2006.01.016 (DOI)
    Note
    Original publication: Andersson, J.M., Wallin, E., Helmersson, U., Kreissig, U. and Münger, E.P., Phase control of Al2O3 thin films grown at low temperatures, 2006, Thin Solid Films, (513), 1-2, 57-59. http://dx.doi.org/10.1016/j.tsf.2006.01.016. Copyright: Elsevier B.V., http://www.elsevier.com/ Available from: 2007-03-02 Created: 2007-03-02 Last updated: 2013-10-30Bibliographically approved
    2. Ab initio studies of Al, O, and O2 adsorption on α-Al2O3 (0001) surfaces
    Open this publication in new window or tab >>Ab initio studies of Al, O, and O2 adsorption on α-Al2O3 (0001) surfaces
    Show others...
    2006 (English)In: Physical Review B. Condensed Matter and Materials Physics, ISSN 1098-0121, E-ISSN 1550-235X, Vol. 74, no 12, 125409-1-125409-9 p.Article in journal (Refereed) Published
    Abstract [en]

    The interactions of Al, O, and O2 with different α- Al2O3 (0001) surfaces have been studied using ab initio density functional theory methods. All three surface terminations obtainable by cleaving the bulk structure [single Al-layer (AlO), double Al-layer (AlAl), and O terminations] have been considered, as well as a completely hydrogenated O-terminated surface. Adsorbed Al shows strong ioniclike interaction with the AlO - and O-terminated surfaces, and several metastable adsorption sites are identified on the O-terminated surface. On the completely hydrogenated surface, however, Al adsorption in the bulk position is found to be unstable or very weak for the studied configurations of surface H atoms. Atomic O is found to interact strongly with the AlAl -terminated surface, where also O2 dissociative adsorption without any appreciable barrier is observed. In contrast, O adsorption on the AlO -terminated surface is metastable relative to molecular O2. On the O-terminated surface, we find the creation of O surface vacancies to be plausible, especially upon exposure to atomic O at elevated temperatures. The results are mainly discussed in the context of alumina thin film growth and provide insight into phenomena related to, e.g., preferred adsorption sites and effects of hydrogen on the growth.

    Place, publisher, year, edition, pages
    College Park, MD, United States: American Physical Society, 2006
    National Category
    Physical Sciences
    Identifiers
    urn:nbn:se:liu:diva-10427 (URN)10.1103/PhysRevB.74.125409 (DOI)000240872500080 ()
    Note

    Original publication: E. Wallin, J.M. Andersson, E.P. Münger, V. Chirita & U. Helmersson, Ab initio studies of Al, O, and O2 adsorption on α- Al2 O3 (0001) surfaces, 2006, Physical Review B, (74), 125409. http://dx.doi.org/10.1103/PhysRevB.74.125409. Copyright: The America Physical Society, http://prb.aps.org/

    Available from: 2007-12-12 Created: 2007-12-12 Last updated: 2014-06-18Bibliographically approved
    3. Influence of residual water on magnetron sputter deposited crystalline Al2O3 thin films
    Open this publication in new window or tab >>Influence of residual water on magnetron sputter deposited crystalline Al2O3 thin films
    2008 (English)In: Thin Solid Films, ISSN 0040-6090, Vol. 516, no 12, 3877-3883 p.Article in journal (Refereed) Published
    Abstract [en]

    The effects of residual water on the phase formation, composition, and microstructure evolution of magnetron sputter deposited crystalline alumina thin films have been investigated. To mimic different vacuum conditions, depositions have been carried out with varying partial pressures of H2O. Films have been grown both with and without chromia nucleation layers. It is shown that films deposited onto chromia nucleation layers at relatively low temperatures (500 °C) consists of crystalline alpha-alumina if deposited at a low enough total pressure under ultra high vacuum (UHV) conditions. However, as water was introduced a gradual increase of the gamma phase content in the film with increasing film thickness was observed. At the same time, the microstructure changed drastically from a dense columnar structure to a structure with small, equiaxed grains. Based on mass spectrometry measurements and previous ab initio calculations, we suggest that either bombardment of energetic negative (or later neutralized) species being accelerated over the target sheath voltage, adsorbed hydrogen on growth surfaces, or a combination of these effects, is responsible for the change in structure. For films containing the metastable gamma phase under UHV conditions, no influence of residual water on the phase content was observed. The amounts of hydrogen incorporated into the films, as determined by elastic recoil detection analysis, were shown to be low. Overall, the results demonstrate that residual water present during film growth drastically affects film properties, also in cases where the hydrogen incorporation is found to be low.

    Place, publisher, year, edition, pages
    ScienceDirect, 2008
    Keyword
    Aluminum oxide, Phase formation, Sputtering, Water
    National Category
    Physical Sciences
    Identifiers
    urn:nbn:se:liu:diva-11476 (URN)10.1016/j.tsf.2007.07.135 (DOI)
    Note
    Original publication: E. Wallin, J.M. Andersson, M. Lattemann, and U. Helmersson, Influence of residual water on magnetron sputter deposited crystalline Al2O3 thin films, 2008, Thin Solid Films, (516), 12, 3877-3883. http://dx.doi.org/10.1016/j.tsf.2007.07.135. Copyright: Elsevier B.V., http://www.elsevier.com/Available from: 2008-04-03 Created: 2008-04-03 Last updated: 2013-10-30Bibliographically approved
    4. Low-temperature alpha-alumina thin film growth: ab initio studies of Al adatom surface migration
    Open this publication in new window or tab >>Low-temperature alpha-alumina thin film growth: ab initio studies of Al adatom surface migration
    2009 (English)In: JOURNAL OF PHYSICS D-APPLIED PHYSICS, ISSN 0022-3727, Vol. 42, no 12, 125302- p.Article in journal (Refereed) Published
    Abstract [en]

    Investigations of activation energy barriers for Al surface hopping on alpha-Al2O3 (0 0 0 1) surfaces have been carried out by means of first-principles density functional theory calculations and the nudged elastic band method. Results show that surface diffusion on the (most stable) Al-terminated surface is relatively fast with an energy barrier of 0.75 eV, whereas Al hopping on the O-terminated surface is slower, with barriers for jumps from the two metastable positions existing on this surface to the stable site of 0.31 and 0.99 eV. Based on this study and on the literature, the governing mechanisms during low-temperature alpha-alumina thin film growth are summarized and discussed. Our results support suggestions made in some previous experimental studies, pointing out that limited surface diffusivity is not the main obstacle for alpha-alumina growth at low-to-moderate temperatures, and that other effects should primarily be considered when designing novel processes for low-temperature alpha-alumina deposition.

    National Category
    Natural Sciences
    Identifiers
    urn:nbn:se:liu:diva-19393 (URN)10.1088/0022-3727/42/12/125302 (DOI)
    Note
    Original Publication: Erik Wallin, Peter Münger, Valeriu Chirita and Ulf Helmersson, Low-temperature alpha-alumina thin film growth: ab initio studies of Al adatom surface migration, 2009, JOURNAL OF PHYSICS D-APPLIED PHYSICS, (42), 12, 125302. http://dx.doi.org/10.1088/0022-3727/42/12/125302 Copyright: Iop Publishing Ltd http://www.iop.org/ Available from: 2009-06-29 Created: 2009-06-22 Last updated: 2013-10-30Bibliographically approved
    5. Hysteresis-free reactive high power impulse magnetron sputtering
    Open this publication in new window or tab >>Hysteresis-free reactive high power impulse magnetron sputtering
    2008 (English)In: Thin Solid Films, ISSN 0040-6090, Vol. 516, no 18, 6398-6401 p.Article in journal (Refereed) Published
    Abstract [en]

    High power impulse magnetron sputtering (HIPIMS) of an Al target in Ar/O2 mixtures has been studied. The use of HIPIMS is shown to drastically influence the process characteristics compared to conventional sputtering. Under suitable conditions, oxide formation on the target as the reactive gas flow is increased is suppressed, and the hysteresis effect commonly observed as the gas flow is varied during conventional sputtering can be reduced, or even completely eliminated, using HIPIMS. Consequently, stoichiometric alumina can be deposited under stable process conditions at high rates. Possible explanations for this behavior as well as a model qualitatively describing the process are presented.

    Keyword
    Reactive Sputtering, High Power Impulse Magnetron Sputtering, Alumina, Process modeling
    National Category
    Physical Sciences
    Identifiers
    urn:nbn:se:liu:diva-15028 (URN)10.1016/j.tsf.2007.08.123 (DOI)
    Note
    Original publication: E. Wallin and U. Helmersson, Hysteresis-free reactive high power impulse magnetron sputtering, 2008, Thin Solid Films, (516), 18, 6398-6401.http://dx.doi.org/10.1016/j.tsf.2007.08.123. Copyright: Elsevier B.V., http://www.elsevier.com/Available from: 2008-10-10 Created: 2008-10-10 Last updated: 2013-10-30Bibliographically approved
    6. Synthesis of α-Al2O3 thin films using reactive high power impulse magnetron sputtering
    Open this publication in new window or tab >>Synthesis of α-Al2O3 thin films using reactive high power impulse magnetron sputtering
    2008 (English)In: Europhysics letters, ISSN 0295-5075, Vol. 82, no 3, 36002- p.Article in journal (Refereed) Published
    Abstract [en]

    α-alumina coatings have been deposited directly onto cemented-carbide and Mo substrates at a temperature as low as 650 °C using reactive high-power impulse magnetron sputtering (HiPIMS) of Al in an Ar/O2 gas mixture. The coatings consisted of plate-like crystallites, as revealed by scanning electron microscopy. α phase growth was retained over the studied range of substrate bias voltages (from floating potential up to -100 V), with films exhibiting a slightly denser microstructure at higher bias voltages. X-ray diffraction indicated that the α-alumina grains had a preferred orientation of (0001)-planes perpendicular to the substrate surface. X-ray analysis of films deposited at 575 °C indicated the presence of γ-alumina, whereas films grown at 500 °C or lower were X-ray amorphous.

    National Category
    Physical Sciences
    Identifiers
    urn:nbn:se:liu:diva-15354 (URN)10.1209/0295-5075/82/36002 (DOI)
    Note
    Original Publication: Erik Wallin, T. I. Selinder, M. Elfwing and Ulf Helmersson, Synthesis of α-Al2O3 thin films using reactive high power impulse magnetron sputtering, 2008, Europhysics letters, (82), 36002. http://dx.doi.org/10.1209/0295-5075/82/36002 Copyright: EDP Sciences. http://publications.edpsciences.org/ Available from: 2009-02-22 Created: 2008-11-05 Last updated: 2013-10-30Bibliographically approved
    7. α-alumina coatings on WC/Co substrates by physical vapor deposition
    Open this publication in new window or tab >>α-alumina coatings on WC/Co substrates by physical vapor deposition
    2009 (English)In: International journal of refractory metals & hard materials, ISSN 0958-0611, Vol. 27, no 2, 507-512 p.Article in journal (Refereed) Published
    Abstract [en]

    Physical vapor deposition coatings for cutting tools may be deposited by, e.g. reactive magnetron sputtering. Alumina growth in Ar/O2 gas mixtures gives rise to problems due to insulating layers on targets, and hysteresis effects with respect to oxygen gas flow. In this paper is described a technology for the deposition of crystalline alumina: reactive high power impulse magnetron sputtering. Pure Al was used as target material, and the cemented carbide (WC/Co) substrates were kept at 500-650 ºC. Hysteresis effects with respect to oxygen gas flow were alleviated, which enabled stable growth at a high deposition rate. The high power impulses were helpful in obtaining a crystalline oxide coating. X-ray diffraction and crosssection transmission electron microscopy showed that α-alumina films were formed. Technological testing of these PVD alumina coatings, with state-of-the-art AlTiN as benchmark, showed significantly improved crater wear resistance in steel turning.

    Keyword
    HiPIMS, HPPMS, ionized-PVD, alumina, corundum
    National Category
    Physical Sciences
    Identifiers
    urn:nbn:se:liu:diva-15359 (URN)10.1016/j.ijrmhm.2008.10.007 (DOI)
    Note
    On the day of defence date the status of article VII was: Accepted. Original Publication: T.I. Selinder, E. Coronel, Erik Wallin and Ulf Helmersson, α-alumina coatings on WC/Co substrates by physical vapor deposition, 2009, International journal of refractory metals & hard materials, (27), 2, 507-512. http://dx.doi.org/10.1016/j.ijrmhm.2008.10.007 Copyright: Elsevier Science B.V., Amsterdam. http://www.elsevier.com/ Available from: 2009-02-23 Created: 2008-11-05 Last updated: 2013-10-30Bibliographically approved
  • 11. Olovsson, Lars
    et al.
    Nilsson, Larsgunnar
    Linköping University, The Institute of Technology. Linköping University, Department of Mechanical Engineering, Solid Mechanics.
    Simonsson, Kjell
    Linköping University, The Institute of Technology. Linköping University, Department of Mechanical Engineering, Solid Mechanics.
    An ALE formulation for the solution of two-dimensional metal cutting problems1999In: Computers & structures, ISSN 0045-7949, Vol. 72, 497-507 p.Article in journal (Refereed)
  • 12.
    Edling, Erik
    et al.
    Linköping University, Department of Computer and Information Science, Human-Centered systems.
    Östergren, Emil
    Linköping University, Department of Computer and Information Science, Human-Centered systems.
    An analysis of microservice frameworks2017Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [en]

    Microservice architecture has entered the industry to solve some of the problems with the monolithic architecture. However, this architecture comes with its own set of problems. In order to solve the microservice architecture problems while also providing additional functionalities, microservice frameworks have been developed. In this thesis, microservice frameworks were compared and thereafter two were chosen to implement a small part of a large monolithic system as microservices. This was done in order to see how well they could implement the different functionalities that the frameworks provided in relation to the benefits and the cross-cutting concerns of the microservice architecture which are concerns that is applicable to the entire system. The results showed that the frameworks embraced the benefits of the microservice architecture in the aspects of maintainability and scalability. However, in the terms of being able to change frameworks in the pursuit of newer technologies there were problems. Some functionalities such as service discovery requires all of the new services created to use the same mechanism in order to create a unified system. There were also problems caused by the load balancing mechanism provided by the frameworks used in this thesis. The load balancing mechanism made the system unable to send large data files which was crucial for the system that was to be implemented as a microservice system.

  • 13.
    Karlsson, Magnus
    Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, The Institute of Technology.
    Analysing strategic energy-related investments in process industries: applied studies at a pulp and board mill2002Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The potential to reduce energy demand in industrial applications is often substantiaL Since energy cost represents a considerable share of the value added in several categories of process industries, a great potential exists for cutting costs through investment, for instance in energy efficiency improvements. However, industrial energy systems form complex relations not only within the industrial unit, but also in the interaction with their surroundings. Consequently, issues such as energy prices and governmental regulations influence the systems to varying extents. At the moment environmental issues, as manifested in the Kyoto agreement, and the new common European electricity market are in focus and are likely to influence the different boundary conditions that face European industries. Therefore, when major investments are to take place, changes in such boundary conditions need to be considered.

    Analysing potential investments in industrial energy systems require advanced methods that manage these complex relations and interactions and concurrently consider technical, economic and environmental issues. The purpose of the thesis is to develop and co-ordinate such methods and apply them to investments in an existing process industry. A method based on optimisation is used as the main tool for analysis. Other methods are applied as complements, for example to manage different aggregation levels and to facilitate sensitivity analyses.

    A pulp and board mill in central Sweden is used as a case study, where investments and changes in the utility systems and the main processes are analysed. These investments are subject to changes in boundary conditions and other mill-specific changes, showing both potentially interesting investments, and also the extensive influence of different boundary conditions. It is also shown that the methods used are appropriate for the purpose at hand.

    List of papers
    1. Co-ordination of pinch technology and the MIND method: applied to a Swedish board mill
    Open this publication in new window or tab >>Co-ordination of pinch technology and the MIND method: applied to a Swedish board mill
    2002 (English)In: Applied Thermal Engineering, ISSN 1359-4311, E-ISSN 1873-5606, Vol. 22, no 2, 133-144 p.Article in journal (Refereed) Published
    Abstract [en]

    By combining the pinch technology and the MIND method, it is possible to identify beneficial and energy-efficient measures in a complex industrial energy system. By tackling a problem on the two different aggregation levels, the result is thoroughly evaluated and durable measures are achieved. The strength of the combination of methods is elucidated in a case study where a Scandinavian pulp and paper mill is analysed. The studied problem concerns pre-evaporation of effluents in a board mill using excess heat. Different alternatives are evaluated, taking into account economic, technical and practicable constraints. The results show that it is cost-effective to pre-evaporate the effluent using excess heat in the studied mill.

    Keyword
    Effluent, Energy, Energy efficiency, Evaporation, Excess heat, Industrial energy system, MIND, Optimisation, Pinch technology, Process integration, Pulp and paper
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-46976 (URN)10.1016/S1359-4311(01)00080-1 (DOI)
    Available from: 2009-10-11 Created: 2009-10-11 Last updated: 2013-02-11
    2. Sensitivity analysis of investments in the pulp and paper industry: on investments in the chemical recovery cycle at a board mill
    Open this publication in new window or tab >>Sensitivity analysis of investments in the pulp and paper industry: on investments in the chemical recovery cycle at a board mill
    2002 (English)In: International journal of energy research (Print), ISSN 0363-907X, E-ISSN 1099-114X, Vol. 26, no 14, 1253-1267 p.Article in journal (Refereed) Published
    Abstract [en]

    In the pulp and paper industry, energy costs represents a relatively large proportion of the value of production. When investing in new equipment, considerations concerning boundary conditions, such as electricity and oil prices, are therefore of great importance. A vital requirement is the identification of other key parameters influencing production costs as well as possible interaction between these parameters. In this paper, a sensitivity analysis is accomplished by using an optimization model that minimizes the system cost combined with a systematic approach involving a statistical method.

    The paper analyses the possibilities of investing in a new chemical recovery cycle, including a new recovery boiler and evaporation plant, at a Swedish board mill. The study includes a survey of future changes, together with forecasts of boundary conditions, such as changes in the price of electricity and oil. Interactions between different parameters are also examined.

    Keyword
    optimization, energy efficiency, industrial energy system, pulp and paper, interaction, factorial design
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-39955 (URN)10.1002/er.848 (DOI)51861 (Local ID)51861 (Archive number)51861 (OAI)
    Available from: 2009-10-10 Created: 2009-10-10 Last updated: 2013-02-11
    3. A systems approach to the reduction of oil demand in a Swedish board mill
    Open this publication in new window or tab >>A systems approach to the reduction of oil demand in a Swedish board mill
    2004 (English)In: Energy, ISSN 0360-5442, Vol. 29, no 1, 103-124 p.Article in journal (Refereed) Published
    Abstract [en]

    The possibility of reducing oil demand in the board mill at Skoghall, operated by Stora Enso, is analysed from a systems perspective. Identification of different key factors influencing the potential for reducing oil demand includes measures within the mill, e.g. steam reduction measures, and boundary conditions, such as electricity prices. Different key factors influence each other to different extents, indicating that an analysis concerning interactions between the different factors is also vital. A survey of these factors influencing oil demand has been carried out and a sensitivity analysis, including a factorial design method, has been applied to the subject.

    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-22917 (URN)10.1016/j.energy.2003.08.003 (DOI)2272 (Local ID)2272 (Archive number)2272 (OAI)
    Available from: 2009-10-07 Created: 2009-10-07 Last updated: 2013-02-11
    4. Cost-efficient CO2-reduction in the pulp and paper industry: a case study
    Open this publication in new window or tab >>Cost-efficient CO2-reduction in the pulp and paper industry: a case study
    2002 (English)In: International Conference on Sustainable Energy Technologies, 2002, Porto, Portugal: FEUP , 2002, EES58- p.Conference paper, Published paper (Refereed)
    Abstract [en]

    It is generally accepted that human activities have a large influence on global climate. In order to minimize human impact on global warming, regulations and agreements may be introduced for all CO2‑generating sectors. Therefore, measures to reduce CO2-emissions will be of importance to the industrial sector. Strategic decisions and long-term thinking are needed to comply with the regulations and to fulfil the agreements.

    The pulp and paper industry is an energy intensive sector with relatively large potentials to accomplish energy efficiency measures that result in reduction of CO2-emissions. To settle the cost-effectiveness for each measure a number of system parameters have to be considered, such as investment costs, boundary conditions and reference systems.

    This paper presents two methods, pinch technology and the MIND method. These methods are used for analysis of industrial energy systems considering different parameters and aspects. Pinch technology is used for thermodynamic and economic evaluation of process integration possibilities and the MIND method is used for strategic evaluation of different energy efficiency measures. Foundation for long-term decision-making can be obtained by co-ordinating the results from the two methods. In this paper, cost-effectiveness has been determined for different energy efficiency measures. The measures are non-conventional evaporation and heat pumping. The case studied is from a Swedish board mill. Economic potentials and consequences for these CO2-reducing measures are discussed from both an industrial and a societal perspective.

    Place, publisher, year, edition, pages
    Porto, Portugal: FEUP, 2002
    Keyword
    MIND, Pinch, Industrial energy systems, CO2, pulp and paper
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-39952 (URN)51858 (Local ID)51858 (Archive number)51858 (OAI)
    Conference
    1st International Conference on Sustainable Energy Technologies, 12-14 June 2002, Porto, Portugal
    Available from: 2009-10-10 Created: 2009-10-10 Last updated: 2013-02-11
    5. Increasing the use of wood fuel in a pulp and paper mill: investment opportunity and external costs
    Open this publication in new window or tab >>Increasing the use of wood fuel in a pulp and paper mill: investment opportunity and external costs
    2002 (English)In: Proceedings of the 10th Biennal Bioenergy Conference, 2002, 174- p.Conference paper, Published paper (Refereed)
    Abstract [en]

    Wood fuel is a by-product produced in large quantities in the pulp and paper industry. It is a relatively cheap energy carrier that can be used to satisfy the internal demand for heat and electricity. Furthermore, it can replace the use of fossil fuels and thereby reduce emissions of CO2 and the related external costs. The aim of this study is to analyze the economics of using more wood fuel for energy purposes, as well as the economics of using wood fiber sludge as a fuel instead of delivering it to landfills. A pulp and paper mill in Sweden is analyzed and the study focuses on providing a demand for heat and electricity. An energy system model based on mixed integer linear programming is used to perform the study. The analysis illustrates the investment opportunity of a new boiler fuelled with bark and sludge. A business economic approach is compared with a socio-economic approach, in which some external costs are considered. The result of the comparison is that the investment opportunity for a wood fuel-boiler is greater when the external cost of production is considered. Furthermore, the amount of emissions associated with the energy conversion and related external costs is estimated for the different cases.

    Keyword
    optimization, industrial energy system, pulp and paper, investment, external costs, bioenergy
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-39956 (URN)51862 (Local ID)51862 (Archive number)51862 (OAI)
    Conference
    10th Biennal Bioenergy Conference, Boise, Idaho USA, 22-26 September
    Available from: 2009-10-10 Created: 2009-10-10 Last updated: 2013-02-11
    6. A pulp and paper mill in the deregulated electricity market: strategies for electricity production
    Open this publication in new window or tab >>A pulp and paper mill in the deregulated electricity market: strategies for electricity production
    (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    The deregulated electricity market has changed the prerequisites for the different actors in the market, both electricity producing companies and electricity purchasers. Companies may purchase electricity directly on the spot market and/ or use different derivatives, such as forwards and futures, as hedging instruments. There are various strategies for acting in the market and this paper explores alternative strategies for a Swedish board mill where hedging contracts to secure the price of electricity cover part of the electricity demand. The remaining demand is purchased on the spot market or produced on site. The back-pressure turbines on site are subject to possible changes in order to determine whether it is profitable to make additional investments aimed at reducing costs.

    Producing electricity close to the demand is a favourable alternative due to reduced losses in the grid and a lesser risk of power failure. Using back-pressure turbines on site meets these requirements and may also help to reduce the risk of power shortages. In certain situations, offering electricity production when there is a lack of electric power in the national grid is a possible alternative aimed at increasing income.

    The result shows that the choice of hedging strategy strongly influences the possibility of reducing costs. It is also shown that the different hedging strategies depend on factors such as the amount of electricity produced on site and the spot price.

    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-88511 (URN)
    Available from: 2013-02-11 Created: 2013-02-11 Last updated: 2013-02-11
    7. Industry and the energy market - optimal choice of measures using the MIND method
    Open this publication in new window or tab >>Industry and the energy market - optimal choice of measures using the MIND method
    2002 (English)In: CRIS Conference on Power Systems and Communications Infrastructures for the future, 2002, China: CRIS, International Institute for Critical Infrastructures , 2002Conference paper, Published paper (Refereed)
    Abstract [en]

    No abstract available.

    Place, publisher, year, edition, pages
    China: CRIS, International Institute for Critical Infrastructures, 2002
    Keyword
    MIND, Industrial energy systems
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-39960 (URN)51866 (Local ID)51866 (Archive number)51866 (OAI)
    Conference
    Power Systems and Communication Systems Infrastructures for the Future International Conference (CRIS'2002) September 23-27, 2002, Beijing, China
    Available from: 2009-10-10 Created: 2009-10-10 Last updated: 2013-02-11
  • 14.
    Sadrossadat, Mohsen
    et al.
    Linköping University, Department of Management and Engineering, Engineering Materials. Linköping University, The Institute of Technology.
    Peng, Ru
    Linköping University, Department of Management and Engineering, Engineering Materials. Linköping University, The Institute of Technology.
    Johansson, Sten
    Linköping University, Department of Management and Engineering, Engineering Materials. Linköping University, The Institute of Technology.
    Analysis of residual stress development during thermal processing of Al-Si alloys2010Conference paper (Refereed)
    Abstract [en]

    Residuals stresses can be present in almost every industrial component. Manufacturing processes such as casting, welding, and heat treatment are the most common causes of residual stresses. Thermal residual stresses could be developed in a component during heat treatment process as a result of non-uniform heating or cooling operations. In this study, experiments were carried out to develop insights into and understanding of the residual stresses that can arise during thermal treatments of Al-Si components. Due to the complexity of residual stresses analysis in real components, a common mixed-section casting was employed. In order to fulfill the requirements of performing different thermal treatments, a special cooling apparatus was designed and built. A number of the casting components of an Al-Si alloy were annealed for stress relief, and then removed from the furnace and cooled with different water flow rates. Then, the amount of accumulated residual stresses in the components was measured relaxation of stress using cutting. Thermal analysis and residual stress measurement for different thermal treatment regimes showed that by choosing a specific holding temperature before direct cooling, the value of residual stress increases linearly with flow rate of cooling. On the other hand, for a constant value of cooling water flow, ∆Tmax and residual stress level decreases when the value of base temperature of furnace decreases. Moreover, the cutting method can be a suitable method for measuring thermal residual stresses in Al-Si components and thermal analysis is a powerful technique to predict residual stresses.

  • 15.
    Zhou, Jinming
    et al.
    Division of Production and Materials Engineering, Lund university.
    Bushlya, Volodymyr
    Division of Production and Materials Engineering, Lund university.
    Peng, Ru
    Linköping University, Department of Management and Engineering, Engineering Materials. Linköping University, The Institute of Technology.
    Chen, Zhe
    Linköping University, Department of Management and Engineering, Engineering Materials. Linköping University, The Institute of Technology.
    Johansson, Sten
    Linköping University, Department of Management and Engineering, Engineering Materials. Linköping University, The Institute of Technology.
    Stahl, Jan-Erik
    Division of Production and Materials Engineering, Lund university.
    Analysis of Subsurface Microstructure and Residual Stresses in Machined Inconel 718 with PCBN and Al2O3-SiCw Tools2014In: 2ND CIRP CONFERENCE ON SURFACE INTEGRITY (CSI), Elsevier, 2014, Vol. 13, 150-155 p.Conference paper (Refereed)
    Abstract [en]

    Subsurface microstructural alterations and residual stresses caused by machining significantly affect component lifetime and performance by influencing fatigue, creep, and stress corrosion cracking resistance. Assessing the surface quality of a machined part by characterizing subsurface microstructural alterations and residual stresses is essential for ensuring part performance and lifetime in aero-engines and power generators. This comparative study characterizes and analyzes subsurface microstructural alterations and residual stresses in Inconel 718 subjected to high-speed machining with PCBN and whisker-reinforced ceramic cutting tools. Effects of cutting tool materials and microgeometry on subsurface deformation, microstructural alterations, and residual stresses were investigated. Surface and subsurface regions of machined specimens were investigated using X-ray diffraction, electron channeling contrast imaging, and electron back-scatter diffraction to characterize microstructural alterations and measure deformation intensity and depth.

  • 16.
    Johansson Jöesaar, Mats P.
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Nanostructured Materials. Linköping University, The Institute of Technology. Seco Tools AB, Fagersta, Sweden.
    Norrby, Niklas
    Linköping University, Department of Physics, Chemistry and Biology, Nanostructured Materials. Linköping University, The Institute of Technology.
    Ullbrand, Jennifer
    Linköping University, Department of Physics, Chemistry and Biology, Nanostructured Materials. Linköping University, The Institute of Technology.
    Saoubi, R.
    Seco Tools AB, Fagersta, Sweden.
    Odén, Magnus
    Linköping University, Department of Physics, Chemistry and Biology, Nanostructured Materials. Linköping University, The Institute of Technology.
    Anisotropy effects onmicrostructure and properties in decomposed arc evaporated Ti1-xAlxN coatings during metal cutting2013In: Surface & Coatings Technology, ISSN 0257-8972, E-ISSN 1879-3347, Vol. 235, no 25, 181-185 p.Article in journal (Refereed)
    Abstract [en]

    Anisotropy effects on the spinodal decomposition in cathodic arc evaporated cubic “phase c-Ti1−xAlxN coatingshave been studied with respect to composition, microstructure and hardness properties before and after a continuousturning operation. Coatings are simultaneously being exposed to both a high temperature and high pressureduring the metal cutting process. As evident from the current results, a high Al content coating, x = 0.66,when exposed to such extreme conditions decomposes into cubic c-AlN and c-TiN-rich domains. In this case,the evolving microstructure comprises interconnected spatially periodic, elongated and coherent cubic c-AlNand c-TiN-rich regions aligned along elastic compliant b100N crystal direction. A significantly different microstructurewith randomly oriented domains is observed for a coating with an elemental composition closer tothe isotropic limit, x = 0.28, exposed under the same conditions. From a coating hardness perspective, thenanoindentation results display a minor age hardening effect for the c-Ti1−xAlxN coating grown at x = 0.28while the coating grown with x = 0.66 exhibits a significant age-hardening effect of about 18%. We concludethat both microstructure and age hardening behavior during spinodal decomposition of c-Ti1−xAlxN correlateto the relative amount ofmetal Ti/Al ratio and consequently to the elastic anisotropy of the as-grown coatingmaterial.These results provide newinsights to the understanding of improvedwear resistance of c-Ti1−xAlxN withAl content during metal cutting.

  • 17.
    Andersson, Lotta
    Linköping University, The Tema Institute.
    Annual variability of nitrogen concentrations and export from forested catchments: A consequence of climatic variability, sampling strategies or human interference?2000In: Boreal environment research, ISSN 1239-6095, Vol. 5, no 3, 221-233 p.Article in journal (Refereed)
    Abstract [en]

    This study was based on the data from 18 years of monitoring in six forested catchments. The aim was to find links between annual estimates of export and concentrations of NO3-N and organic N and hydroclimatological factors, sampling strategy and human interference. A topography-based wetness index was used to assess whether the effects of forestry activities depended on prevailing wetness conditions. For organic N, annual runoff was the main explaining factor in three catchments. The flow condition during sampling was for organic N the main explaining factor in three and for NO3-N in one catchment. Effects of clear-cutting of 14% in one catchment were observed. For organic N, the model could be improved by considering clear-cutting in wet areas only. The southernmost catchment, but also the northernmost catchment with the lowest deposition, showed links to atmospheric deposition, demonstrating that deposition can cause a significant direct response in streamwater concentrations in nutrient-poor catchments.

  • 18.
    Kvist, Joanna
    et al.
    Linköping University, Department of Medical and Health Sciences, Sports Medicine . Linköping University, Faculty of Health Sciences.
    Gillquist, Jan
    Linköping University, Department of Medical and Health Sciences, Sports Medicine . Linköping University, Faculty of Health Sciences.
    Anterior positioning of tibia during motion after anterior cruciate ligament injury2001In: Medicine & Science in Sports & Exercise, ISSN 0195-9131, E-ISSN 1530-0315, Vol. 33, no 7, 1063-1072 p.Article in journal (Refereed)
    Abstract [en]

    PURPOSE: The purpose of this study was to describe the sagittal tibial translation and EMG activity of muscles v. medialis and lateralis, gastrocnemius, and hamstrings, during common locomotion, in patients with an anterior cruciate ligament deficiency (ACL-def) and uninjured controls.

    METHODS: In 12 ACL-def patients and 17 controls, sagittal tibial translation was registered with the CA-4000 electrogoniometer during level walking, cutting, and stair walking. Tibial position at each flexion angle was expressed relative to the femuro-tibial position at passive knee extension. EMG activity, measured with ME-4000, was normalized to the individual maximum isometric voluntary contraction for each muscle.

    RESULTS: During the weight-bearing phase of motion, the tibia was anteriorly positioned in all legs. In the injured leg, the tibia translated more rapidly to an anterior position that was maintained for a longer time during the gait cycle. In the noninjured knees, motions with increased load lead to an increased anterior tibial translation in contrast to the injured knees, where the maximum displacement was already reached during level walking. The quadriceps and gastrocnemius muscles were simultaneously active during stance phase. Hamstrings were mainly active when the knee was close to extension and translation increased in spite of this activity.

    CONCLUSIONS: The mechanism of the anterior positioning of tibia is qualitatively similar in the normal and the injured knee, but that position is obtained much further forward in the ACL deficient knee. Quadriceps and gastrocnemius muscles seem to work synergistically to stabilize the knee by maintaining the anterior position of tibia during weight-bearing motion. The role of hamstrings to restrict anterior translation is questioned.

  • 19.
    Flisberg, Patrik
    Linköping University, Department of Mathematics, Optimization . Linköping University, The Institute of Technology.
    Application of operations research in operative planning in the forest industry2007Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The focus of this thesis is the use of Operations Research for pplications in the forest industry. Optimization models and methods have been developed for problems in the forest supply chain and they have been integrated in decision support systems. The problems considered in this thesis are operative with a planning horizon of less than a month. Short solution times for the methods and the feasibility of the models used are important aspects. The body of this thesis consists of eight research papers where six of them consider operative problems and follows the forest supply chain. The industrial applications include routing of forwarders, routing of logging trucks, a process control problem, and roll cutting problems. The other two papers consider an operative planning problem in the home care sector. They are spin offs from one of the other projects in this thesis. In these applications both linear and nonlinear problems occur.

    The forwarding problem is to decide routes for forwarders to pick up the small piles of logs the harvesters have left in the harvest areas. The forwarders then put the logs adjacent to forest roads. The logging truck problem is to decide routes for logging trucks to pick up the piles created by the forwarders and transport them to demand points, for example pulp or paper mills. The process control problem appear in the bleaching stage of a pulp mill where the control variables are the bleaching chemical charges. The cost of bleaching chemicals is minimized while a finishing brightness within target values is ensured. Mainly two roll cutting problems are studied. One is to minimize the number of cutting patterns and one is to minimize the number of reels when defects in the papper reels are considered. The solution methods developed for the forwarding problem have also been applied to a routing problem which appears in staff planning for home care operations.

    The different DSS developed and implemented have been tested and several are in daily industrial use. In each of the papers, we have developed robust OR models and quick and effective OR methods. The savings from using the systems vary but are typically in the range 5-20%.

    List of papers
    1. Optimization based planning tools for routing of forwarders at harvest areas
    Open this publication in new window or tab >>Optimization based planning tools for routing of forwarders at harvest areas
    2007 (English)In: Canadian Journal of Forest Research, ISSN 0045-5067, Vol. 37, no 11, 2153-2163 p.Article in journal (Refereed) Published
    Abstract [en]

    The forwarding of logs at harvest areas once the harvesting is done is planned manually by experienced operators. To improve their efficiency and simplify the planning we have developed and tested a decision support system at a major Swedish forest company. The system is based on a combination of a geographic information system (GIS), global positioning system (GPS), and optimization routines to solve the underlying vehicle routing problem. The routes for the forwarders are found by using a repeated matching algorithm. The solution time is short, and it is possible to find routes dynamically in a real-time environment. The geographic information required is found by using a GPS together with data obtained from the bucking software in the harvesters. To show the routes and location of the forwarder, we make use of a GIS that is connected to the GPS. We report on a study with savings in the distance travelled of 8% and numerical tests on the solution methodology. We also compare the proposed solution method with some well-known routing methods.

    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-47900 (URN)10.1139/X07-065 (DOI)
    Available from: 2009-10-11 Created: 2009-10-11 Last updated: 2012-11-22
    2. A hybrid method based on linear programming and tabu search for routing of logging trucks
    Open this publication in new window or tab >>A hybrid method based on linear programming and tabu search for routing of logging trucks
    2009 (English)In: Computers & Operations Research, ISSN 0305-0548, Vol. 36, no 4, 1122-1144 p.Article in journal (Refereed) Published
    Abstract [en]

    In this paper, we consider an operational routing problem to decide the daily routes of logging trucks in forestry. This industrial problem is difficult and includes aspects such as pickup and delivery with split pickups, multiple products, time windows, several time periods, multiple depots, driver changes and a heterogeneous truck fleet. In addition, the problem size is large and the solution time limited. We describe a two-phase solution approach which transforms the problem into a standard vehicle routing problem with time windows. In the first phase, we solve an LP problem in order to find a destination of flow from supply points to demand points. Based on this solution, we create transport nodes which each defines the origin(s) and destination for a full truckload. In phase two, we make use of a standard tabu search method to combine these transport nodes, which can be considered to be customers in vehicle routing problems, into actual routes. The tabu search method is extended to consider some new features. The solution approach is tested on a set of industrial cases from major forest companies in Sweden.

    Keyword
    Forestry, Routing, Tabu search, Linear Programming, OR in Practice
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-85519 (URN)10.1016/j.cor.2007.12.012 (DOI)
    Available from: 2012-11-21 Created: 2012-11-21 Last updated: 2012-11-22
    3. RuttOpt: a decision support system for routing of logging trucks
    Open this publication in new window or tab >>RuttOpt: a decision support system for routing of logging trucks
    2008 (English)In: Canadian Journal of Forest Research, ISSN 0045-5067, Vol. 38, no 7, 1784-1796 p.Article in journal (Refereed) Published
    Abstract [en]

    We describe the decision support system RuttOpt, which is developed for scheduling logging trucks in the forest industry. The system is made up of a number of modules. One module is the Swedish road database NVDB, which consists of detailed information of all of the roads in Sweden. This also includes a tool to compute distances between locations. A second module is an optimization routine that finds a schedule, i.e., set of routes for all trucks. This is based on a two-phase algorithm where linear programming and a standard tabu search method are used. A third module is a database storing all relevant information. At the center of the system is a user interface where information and results can be viewed on maps, Gantt schedules, and result reports. The RuttOpt system has been used in a number of case studies and we describe four of these. The case studies have been made in both forest companies and hauling companies. The cases range from 10 to 110 trucks and with a planning horizon ranging between 1 and 5 days. The results show that the system can be used to solve large case studies and that the potential savings are in the range 5%–30%.

    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-85521 (URN)10.1139/X08-017 (DOI)
    Available from: 2012-11-21 Created: 2012-11-21 Last updated: 2012-11-22
    4. Pulp fact, not fiction
    Open this publication in new window or tab >>Pulp fact, not fiction
    2005 (English)In: OR/MS Today, ISSN 1085-1038, Vol. 32, no 2, 42-47 p.Article in journal (Refereed) Published
    Abstract [en]

    By taking the guesswork out of the equation, operations research-based process control system helps cut costs, reduce environmental impact at Swedish paper mill.

    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-85522 (URN)
    Available from: 2012-11-21 Created: 2012-11-21 Last updated: 2012-11-27
    5. Optimized on-line process control of bleaching operations with OptCab
    Open this publication in new window or tab >>Optimized on-line process control of bleaching operations with OptCab
    2007 (English)In: Norges Handelshoeyskole. Institutt for Foretaksoekonomi. Discussion Paper, ISSN 1500-4066Article, review/survey (Refereed) Published
    Abstract [en]

    To produce pulp for paper production or as market pulp is a complicated on-line process with many integrated stages that impact the final quality. In the bleaching plant which is at the end of pulp production, the main objective is to increase pulp brightness within specified limits. Here chemical treatments are applied in sequential stages to achieve the right brightness while striving to maintain the pulp strength as unaffected as possible. The raw material, i.e. pulp logs and wood chips from saw mills, differ in quality and properties. Due to this, it is important to continuously update the amount of chemicals added to the pulp in real-time. This is typically done by experienced operators. In this paper, we describe an on-line optimization based decision support system called OptCab that controls the bleaching process at Billerud AB's paper mill in Skärblacka. The solution approach is based on two phases. In phase one, we establish approximations of each of the processes based on process data collected on-line. These approximations are found by solving a set of constrained least square problems and are updated every 15 minutes. In phase two, we formulate an overall nonlinear control problem that links all stages together and aims to minimize the cost of chemicals. This is solved on-line every five minutes. The system has been in operation during the last three years providing a 10% reduction in the use of chemicals. Additional benefits include a more stable brightness quality.

    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-85523 (URN)
    Note

    This is a working paper.

    Available from: 2012-11-21 Created: 2012-11-21 Last updated: 2012-11-22
    6. Roll cutting at paper mills
    Open this publication in new window or tab >>Roll cutting at paper mills
    2002 (English)In: Proceedings of the Control Systems 2002, 2002, 159-163 p.Conference paper, Published paper (Other academic)
    Abstract [en]

    Roll cutting has attracted a great deal of research attention. However, most of the development of models and methods in academic research has not considered some key industrial requirements. These are practical production aspects that often create non-tractable optimization problems. In this paper, we study two important problems and show how these can be solved efficiently in an industrial setting. These are operative roll cutting where the number of reels and different patterns should be minimized and real-time cutting, when defects and quality restrictions on ordered rolls are included.

    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-85524 (URN)
    Conference
    Control Systems 2002, June 3-5, Stockholm, Sweden
    Available from: 2012-11-21 Created: 2012-11-21 Last updated: 2012-11-22
    7. Home care operations
    Open this publication in new window or tab >>Home care operations
    2004 (English)In: OR/MS today, ISSN 1085-1038, Vol. April, 38-43 p.Article in journal (Refereed) Published
    Abstract [en]

    No abstract available.

    National Category
    Mathematics
    Identifiers
    urn:nbn:se:liu:diva-22746 (URN)2060 (Local ID)2060 (Archive number)2060 (OAI)
    Available from: 2009-10-07 Created: 2009-10-07 Last updated: 2012-11-22
    8. Laps Care: an operational system for staff planning of home care
    Open this publication in new window or tab >>Laps Care: an operational system for staff planning of home care
    2006 (English)In: European Journal of Operational Research, ISSN 0377-2217, Vol. 171, no 3, 962-976 p.Article in journal (Refereed) Published
    Abstract [en]

    The health care system in Sweden and many other countries is facing increasing costs. The major reason is the changing age distribution of the population with more elderly people in need of support. At the same time, health care systems are often very labor and staff intensive. In this paper, we focus on a staff planning problem arising in Sweden where people receive home care from the local authorities. The objective is to develop visiting schedules for care providers that incorporate some restrictions and soft objectives. Each visit has a particular task to be performed, for example: cleaning, washing, personal hygiene and/or nursing activities. Each staff member has skills and each client should, if possible, be visited by the same contact person. The operational situation is continuously changing and planning is done each day. We describe the development of a decision support system Laps Care to aid the planners. The system consists of a number of components including information data bases, maps, optimization routines, and report possibilities. We formulate the problem using a set partitioning model and, for a solution method, we make use of a repeated matching algorithm. The system is currently in operation at a number of home care organizations. We report on the practical impact of the system in the health care organization which was involved in the development. The savings are considerably in terms of saved planning time and in the quality of the routes, as well as the measured quality for the clients. Numerical experiments of the system are presented.

    Keyword
    health care; home care; staff planning; modelling; heuristics; optimization; practice of OR
    National Category
    Social Sciences
    Identifiers
    urn:nbn:se:liu:diva-53494 (URN)10.1016/j.ejor.2005.01.011 (DOI)
    Available from: 2010-01-25 Created: 2010-01-25 Last updated: 2012-11-22
  • 20.
    Sjölén, Jacob
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    Arc evaporated wear-resistant nitride coatings for metal cutting tools2008Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    This Thesis is dedicated to increase the understanding of arc evaporated PVD coatings as wear resistant layers on metal cutting tools. The approach is to study coatings that have excellent performance in metal cutting applications, specifically (Ti,Al)N and (Ti,Si)N in terms of thermal and mechanical properties, and to correlate this to their microstructure, stress state, and composition. The effect of addition of oxygen into (Ti,Al)N is also evaluated in terms of structure, chemical bonding, and mechanical properties. It is shown that metastable fcc-(Ti,Al)N coatings separate into Ti-rich and Al-rich fcc-(Ti,Al)N zones via spinodal decomposition at 800 - 1000 °C, which acts as a hardening mechanism. This is followed by nucleation and growth into the stable phases fcc-TiN and hex-AlN at T>1000°C, with subsequent loss of hardness. These structural changes are correlated to the cutting performance, showing that the initial spinodal phase separation improves the performance. The success of (Ti,Al)N in metal cutting applications is, hence, due not only to the well documented oxidation resistance, but also to the spinodal decomposition process, which is active at the typical temperatures at the cutting edge of an engaged cutting insert. The potential subsequent renucleation process is, however, detrimental in metal cutting applications. Oxygen is commonly regarded as a contamination in PVD coating processes due to the risk of formation of insulating layers. This study, however, shows that by using arcevaporation, up to 35 at.% O can be incorporated into (Ti,Al)N coatings without altering its NaCl-structure. 1t is inferred that O substitutes for N in the lattice and (Ti,Al)(O,N) is formed. The incorporation of small amounts of oxygen (up to 13 at.%) improves the cutting performance by reducing the risk of chipping. However, at higher oxygen levels, the wear resistant properties are dramatically reduced. Finally, is shown that it is poss ible to replace at least 14 at.% Ti by Si, without altering the NaCl-structure in (Ti,Si)N coatings. The measured hardness of solid solution fcc-(Ti,Si)N is nearly a linear function of Si-content in the coating (from 31 GPa in TiN up to 45 GPa in (Ti0.86Si0.14)N). The hardness is also retained after annealing at 900 oC for 2h.

    List of papers
    1. Thermal stability of arc evaporated high aluminum-content Ti1−xAlxN thin films
    Open this publication in new window or tab >>Thermal stability of arc evaporated high aluminum-content Ti1−xAlxN thin films
    Show others...
    2002 (English)In: Journal of Vacuum Science & Technology. A. Vacuum, Surfaces, and Films, ISSN 0734-2101, E-ISSN 1520-8559, Vol. 20, no 5, 1815-1823 p.Article in journal (Refereed) Published
    Abstract [en]

    The thermal stability of Ti1−xAlxN films deposited by arc evaporation from Ti–Al cathodes with 67 and 75 at. % aluminum, respectively, has been investigated. The microstructure of as-deposited and isothermally annealed samples were studied using scanning electron microscopy, transmission electron microscopy, and x-ray diffraction. The chemical composition and elemental distribution were determined by energy dispersive x ray (EDX), Rutherford backscattering spectrometry, and EDX mapping. Transmission electron micrographs revealed a dense and columnar microstructure in the as-deposited condition. Films deposited from the 67 at. % cathodes were of cubic NaCl-structure phase, whereas films deposited from the 75 at. % cathodes exhibited nanocrystallites of wurzite-structure hexagonal-phase AlN in a cubic (c)-(Ti,Al)N matrix. Both films were stable during annealing at 900 °C/120 min with respect to phase composition and grain size. Annealing at 1100 °C of films deposited from the 67 at. % cathodes resulted in phase separation of c-TiN and h-AlN, via spinodal decomposition of c-TiN and c-AlN. (Ti,Al)N films undergo extensive stress relaxation and defect annihilation at relatively high temperatures, and aspects of these microstructural transformations are discussed.

    National Category
    Condensed Matter Physics
    Identifiers
    urn:nbn:se:liu:diva-18801 (URN)10.1116/1.1503784 (DOI)
    Available from: 2009-06-08 Created: 2009-06-04 Last updated: 2016-08-31Bibliographically approved
    2. Self-organized nanostructures in the Ti-Al-N system
    Open this publication in new window or tab >>Self-organized nanostructures in the Ti-Al-N system
    Show others...
    2003 (English)In: Applied Physics Letters, ISSN 0003-6951, Vol. 83, no 10, 2049-2051 p.Article in journal (Refereed) Published
    Abstract [en]

    The phenomenon of age hardening could be evidenced in thin film applications. A model system, Ti1-xAlxN was chosen as such coatings are known for their excellent wear resistance enabling improved machining processes like high-speed and dry cutting. Here, we show unambiguously that metastable Ti1-xAlxN coatings initially undergo spinodal decomposition into coherent cubic-phase nanometer-size domains, causing an increase in hardness at elevated temperatures. These intermediate metastable domains transform into their stable phases TiN and AlN during further thermal treatment. Activation energies for the processes indicate defect-assisted segregation of Ti and Al. The findings are corroborated by ab initio calculations. A long-standing discussion on the thermal stability of this important class of ceramics is thus resolved.

    National Category
    Condensed Matter Physics
    Identifiers
    urn:nbn:se:liu:diva-18822 (URN)10.1063/1.1608464 (DOI)
    Available from: 2009-06-08 Created: 2009-06-05 Last updated: 2016-08-31Bibliographically approved
    3. Mechanical properties and machining performance of Ti1−xAlxN-coated cutting tools
    Open this publication in new window or tab >>Mechanical properties and machining performance of Ti1−xAlxN-coated cutting tools
    Show others...
    2005 (English)In: Surface & Coatings Technology, ISSN 0257-8972, E-ISSN 1879-3347, Vol. 191, no 2-3, 384-392 p.Article in journal (Refereed) Published
    Abstract [en]

    The mechanical properties and machining performance of Ti1−xAlxN-coated cutting tools have been investigated. Processing by arc evaporation using cathodes with a range of compositions was performed to obtain coatings with compositions x=0, x=0.25, x=0.33, x=0.50, x=0.66 and x=0.74. As-deposited coatings with x≤0.66 had metastable cubic structures, whereas x=0.74 yielded two-phase coatings consisting of cubic and hexagonal structures. The as-deposited and isothermally annealed coatings were characterised by nanoindentation, scanning electron microscopy (SEM) and X-ray diffraction (XRD). Cutting tests revealing tool wear mechanisms were also performed. Results show that the Al content, x, promotes a (200) preferred crystallographic orientation and has a large influence on the hardness of as-deposited coatings. The high hardness (∼37 GPa) and texture of the as-deposited Ti1−xAlxN coatings are retained for annealing temperatures up to 950 °C, which indicates a superior stability of this system compared to TiN and Ti(C,N) coatings. We propose that competing mechanisms are responsible for the effectively constant hardness: softening by residual stress relaxation through lattice defect annihilation is balanced by hardening from formation of a coherent nanocomposite structure of c-TiN and c-AlN domains by spinodal decomposition. This example of secondary-phase transformation (age-) hardening is proposed as a new route for advanced surface engineering, and for the development of future generation hard coatings.

    Keyword
    Hard coatings; TiAlN; Age hardening; Spinodal decomposition; Transition; Metal nitrides
    National Category
    Condensed Matter Physics
    Identifiers
    urn:nbn:se:liu:diva-18823 (URN)10.1016/j.surfcoat.2004.04.056 (DOI)
    Available from: 2009-06-08 Created: 2009-06-05 Last updated: 2016-08-31Bibliographically approved
    4. Structure and mechanical properties of arc evaporated Ti–Al–O–N thin films
    Open this publication in new window or tab >>Structure and mechanical properties of arc evaporated Ti–Al–O–N thin films
    Show others...
    2007 (English)In: Surface & Coatings Technology, ISSN 0257-8972, Vol. 201, no 14, 6392-6403 p.Article in journal (Refereed) Published
    Abstract [en]

    The structure, mechanical properties, and machining performance of arc evaporated Ti–Al–O–N coatings have been investigated for an Al0.66Ti0.34 target composition and O2/(O2+N2) gas flow-ratio varied between 0 to 24%. The coating structure was analysed using SEM, EDX, XRD, XPS, TEM, and STEM. Mechanical properties were analysed using nanoindentation and the deformation behaviour was analysed by probing the nanoindentation craters. The coatings performances in cutting tests were evaluated in a turning application in low carbon steel (DIN Ck45). It is shown that the addition of oxygen into the arc deposition process leads to the formation of a dual layer structure. It consists of an initial cubic NaCl-structure solid solution phase formed closest to the substrate, containing up to 35 at.% oxygen (O/O+N), followed by steady-state growth of a nanocomposite compound layer comprised of Al2O3, AlN, TiN, and Ti(O,N). The addition of oxygen increases the ductility of the coatings, which improves the performances in cutting tests. At high levels of oxygen, (>13 at.%), however, the performance is dramaticallyreduced as a result of increased crater wear.

    Keyword
    TiAlON; Arc-evaporation; Nanostructure; Mechanical properties
    National Category
    Condensed Matter Physics
    Identifiers
    urn:nbn:se:liu:diva-18825 (URN)10.1016/j.surfcoat.2006.12.006 (DOI)
    Available from: 2009-06-08 Created: 2009-06-05 Last updated: 2016-08-31Bibliographically approved
    5. Influence of Si on the Microstructure of Arc Evaporated (Ti,Si)N Thin Films: Evidence for Cubic Solid Solutions and their Thermal Stability
    Open this publication in new window or tab >>Influence of Si on the Microstructure of Arc Evaporated (Ti,Si)N Thin Films: Evidence for Cubic Solid Solutions and their Thermal Stability
    Show others...
    2005 (English)In: Surface and Coatings Technology, ISSN 0257-8972, Vol. 200, no 5-6, 1535-1542 p.Article in journal (Refereed) Published
    Abstract [en]

    Ti1−xSixN (0 ≤ x ≤ 0.14) thin solid films were deposited onto cemented carbide (WC-Co) substrates by arc evaporation. X-ray diffraction and transmission electron microscopy showed that all films were of NaCl-structure type phase. The as-deposited films exhibited a competitive columnar growth mode where the structure transits to a feather-like nanostructure with increasing Si content. Films with 0 ≤ x ≤ 0.01 had a 111 crystallographic preferred orientation which changed to an exclusive 200 texture for 0.05 ≤ x ≤ 0.14. X-ray photoelectron spectroscopy revealed the presence of Si–N bonding, but no amorphous Si3N4. Band structure calculations performed using a full potential linear muffin tin orbital method showed that for a given NaCl-structure Ti1−xSixN solid solution, a phase separation into cubic SiN and TiN is energetically favorable. The microstructure was maintained for the Ti0.86Si0.14N film annealed at 900 °C, while recrystallization in the cubic state took place at 1100 °C annealing during 2 h. The Si content influenced the film hardness close to linearly, by combination of solid-solution hardening in the cubic state and defect hardening. For x = 0 and x = 0.14, nanoindentation gave a hardness of 31.3 ± 1.3 GPa and 44.7 ± 1.9 GPa, respectively. The hardness was retained after annealing at 900 °C, while it decreased to below 30 GPa for 1100 °C following recrystallization and W and Co interdiffusion.

    Keyword
    Nitrides; Arc evaporation; Transmission electron microscopy (TEM); Thin films; Solid solution; Microstructure
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-14144 (URN)10.1016/j.surfcoat.2005.08.096 (DOI)
    Available from: 2006-11-15 Created: 2006-11-15 Last updated: 2016-08-31
  • 21.
    Wallén, Johanna
    et al.
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, The Institute of Technology.
    Norrlöf, Mikael
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, The Institute of Technology.
    Gunnarsson, Svante
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, The Institute of Technology.
    Arm-Side Evaluation of ILC Applied to a Six-Degrees-of-Freedom Industrial Robot2007Report (Other academic)
    Abstract [en]

    Experimental results from a first-order ILC algorithm applied to a large-size sixdegrees-of-freedom commercial industrial robot are presented. The ILC algorithm is based on measurements of the motor angles, but in addition to the conventional evaluation of the ILC algorithm based on the motor-side error, the tool-path error on the arm side is evaluated using a laser-measurement system. Experiments have been carried out in three operating points using movements that represent typical paths in a laser-cutting application and different choices of algorithm design parameters have been studied. The motor-angle error is reduced substantially in all experiments and the tool-path error is reduced in most of the cases. In one operating point, however, the error does not decrease as much and an oscillatory tool behaviour is observed. Changed filter variables can give worse error reduction in all operating points. To achieve even better performance, especially in difficult operating points, it is concluded that an arm-side measurement, from for example an accelerometer, needs to be included in the learning.

  • 22.
    Wallén, Johanna
    et al.
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, The Institute of Technology.
    Norrlöf, Mikael
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, The Institute of Technology.
    Gunnarsson, Svante
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, The Institute of Technology.
    Arm-Side Evaluation of ILC Applied to a Six-Degrees-of-Freedom Industrial Robot2008In: Proceedings of the 17th IFAC World Congress, 2008, , 13450-13455 p.13450-13455 p.Conference paper (Refereed)
    Abstract [en]

    Experimental results from a first-order ILC algorithm applied to a large-size sixdegrees-of-freedom commercial industrial robot are presented. The ILC algorithm is based on measurements of the motor angles, but in addition to the conventional evaluation of the ILC algorithm based on the motor-side error, the tool-path error on the arm side is evaluated using a laser-measurement system. Experiments have been carried out in three operating points using movements that represent typical paths in a laser-cutting application and different choices of algorithm design parameters have been studied. The motor-angle error is reduced substantially in all experiments and the tool-path error is reduced in most of the cases. In one operating point, however, the error does not decrease as much and an oscillatory tool behaviour is observed. Changed filter variables can give worse error reduction in all operating points. To achieve even better performance, especially in difficult operating points, it is concluded that an arm-side measurement, from for example an accelerometer, needs to be included in the learning.

  • 23.
    Vagin, Mikhail
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Chemical and Optical Sensor Systems. Linköping University, The Institute of Technology.
    Sekretareva, Alina
    Linköping University, Department of Physics, Chemistry and Biology, Chemical and Optical Sensor Systems. Linköping University, The Institute of Technology.
    Sanchez, Rafael
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Lundström, Ingemar
    Linköping University, Department of Physics, Chemistry and Biology, Biosensors and Bioelectronics. Linköping University, The Institute of Technology.
    Winquist, Fredrik
    Linköping University, Department of Physics, Chemistry and Biology, Biosensors and Bioelectronics. Linköping University, The Institute of Technology.
    Eriksson, Mats
    Linköping University, Department of Physics, Chemistry and Biology, Chemical and Optical Sensor Systems. Linköping University, The Institute of Technology.
    Arrays of Screen-Printed Graphite Microband Electrodes as a Versatile Electroanalysis Platform2014In: ChemElectroChem, ISSN 2196-0216, Vol. 1, no 4, 755-762 p.Article in journal (Refereed)
    Abstract [en]

    Arrays of microband electrodes were developed by screen printing followed by cutting, which enabled the realization of microband arrays at the cut edge. The microband arrays of different designs were characterized by physical and electro-chemical methods. In both cases, the methods showed that the microband width was around 5 mm. Semi-steady-state cyclic voltammetry responses were observed for redox probes, and chronocoulometric measurements showed the establishment of convergent diffusion regimes characterized by current densities similar to those of a single microelectrode. The analytical performance of the electrode system and its versatility were illustrated with two electrochemical assays: detection of ascorbic acid through direct oxidation and a mediated glucose biosensor fabricated by dip coating. Due to convergent mass transport, both systems showed an enhancement in their analytical characteristics. The developed approach can be adapted to automated electrode recovery.

  • 24.
    Lykke, Nina
    et al.
    Linköping University, Department of Thematic Studies, The Department of Gender Studies. Linköping University, Faculty of Arts and Sciences.
    Lie, Merete
    Department of interdisciplinary cultural studies, University of Trondheim (NTNU), Trondheim, Norway.
    Assisted Reproduction Across Borders. Feminist  Perspectives on Normalizations, Disruptions and Transmissions: Editorial Introduction2017In: Assisted Reproduction Across Borders: Feminist  Perspectives on Normalizations, Disruptions and Transmissions / [ed] Merete Lie and Nina Lykke, New York: Routledge, 2017, 1-21 p.Chapter in book (Refereed)
    Abstract [en]

    The introduction presents the rationale and main aims of the co-edited volume. It explains the starting points that assisted reproductive technologies (ARTs) in the 21st century are no longer ‘new technology’ or cutting-edge science but are rather regarded as mundane practice, and that the reproductive possibilities opened by ARTs from commercialized transnational traffic in eggs, sperm, embryos and gestational labour to new queer family buildings continue to make legislators perplex and create moral dilemmas leading to all kinds of restrictions and exclusionary practices.  Against this background, the main purpose is defined  as taking stock of this complex situation, and look at the contradictions, disruptions and renegotiations which it generates – a purpose which gives rise to the framing of two more specific aims: 1) to study the social and cultural aspects of ARTs as something that is integrated into both public health services and people’s understanding of common ways to achieve pregnancy, 2) and to do so against the background of data gathered from a wide array of social, cultural and geopolitical contexts, combining a European focus with a strong global outlook, which opens possibilities  to reflect on the workings of different local constraints and enablings. The chapter also provides a detailed reflection on the complementary perspectives of the differently located contributions and the ways they each address one of five overall themes: transnational reproflows, national constraints and conditions, religious and other kinds of fundamentalism, demographic agendas and biopolitics, and ‘new normals’ and their discontents, considered important for a general understanding of  policies, discourses and practices of ARTs in the contemporary world.

      

  • 25.
    Björnsson, Andreas
    et al.
    Linköping University, Department of Management and Engineering, Manufacturing Engineering. Linköping University, The Institute of Technology.
    Lindbäck, Jan Erik
    Saab Aerostructures.
    Johansen, Kerstin
    Linköping University, Department of Management and Engineering, Machine Design. Linköping University, The Institute of Technology.
    Automated Removal of Prepreg Backing Paper - A Sticky Problem2013In: Proceedings of the SAE 2013, Aerotech Congress and Exhibition, 24th-26th September 2013, Montreal,Canada, 2013Conference paper (Refereed)
    Abstract [en]

    Automated solutions for manufacturing composite products based on prepreg often imply Automatic Fiber Placement or Automatic Tape Laying. These systems are generally associated with huge investments. For certain manufacturing applications it is interesting to investigate alternatives to find simpler and less costly automation. One example of an automated system could be the use of a standard industrial robot to pick single prepreg plies from an automated cutting machine and stack them to form a plane laminate. This paper is based on a case illustrating a product from the aircraft manufacturing industry. The case will demonstrate a pick and place concept on a general level and illustrate challenges that must be solved. The challenge selected to be the main focus for this paper is an automated process for backing paper removal. A literature review of different gripping technologies reveals several interesting technologies, and the most promising are tested for backing paper removal. The tests show that an automated removal process can be designed by using standard vacuum grippers in combination with mechanical clamping grippers. In order to lift the backing paper with a vacuum gripper an initial separation between the backing paper and prepreg is needed. This separation is most easily mechanically induced by bending the material. The proposed solution for automatic backing paper removal can be integrated in a manufacturing cell for manufacturing of the studied product.

  • 26.
    Carlsson, Magnus
    et al.
    Linköping University, Department of Mechanical Engineering.
    Kristoffersson, Daniel
    Linköping University, Department of Mechanical Engineering.
    Automatiskt avvägningssystem för obemannad undervattensfarkost2005Independent thesis Basic level (professional degree)Student thesis
    Abstract [en]

    This master thesis work was done at Saab Underwater Systems AB, a company at the cutting edge of underwater technology. Here torpedoes and other underwater vehicles are developed and manufactured. The major customers are navies of different countries, mostly the Swedish navy.

    The aim of this master thesis is to develop, construct and evaluate an automatic Trim System for Unmanned Underwater Vehicles. The task of the system is to change the position of the centre of mass and the vehicle’s total mass or volume. A system like this gives more opportunities like improved low speed properties, manoeuvre ability and energy consumption.

    Different ways to make this change of total mass and position of centre of mass has been discussed and a choice has been done. A system of chosen concept has then been developed, constructed and evaluated. A part of big importance in this report is the work with simulations to predict the performance of the system and its behaviour. Other big parts has been to find suiting components and to develop the control electronics of the system.

  • 27.
    Hultman, Lars
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    Hörling, Anders
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    Auto-organized nanostructures in the Ti-Al-N thin film system2004In: SURFACES AND INTERFACES IN NANOSTRUCTURED MATERIALS AND TRENDS IN LIGA, MINIATURIZATION, AND NANOSCALE MATERIALS: Fifth MPMD Global Innovations Symposium / [ed] Mukhopadhyay, SM; Seal, S; Dahotre, N; Agarwal, A; Smugeresky, JE; Moody, N, John Wiley & Sons, 2004, 163-172 p.Conference paper (Refereed)
    Abstract [en]

    Age hardening by spinodal decomposition in ceramic thin film systems is reviewed. This is a new concept for advanced surface engineering with applications for wear-resistant coatings in machining processes like high-speed and dry cutting. The reactive arc deposition method with relatively low substrate temperatures is employed to produce supersaturated solid solutions of the material by ion-bombardment-induced mixing of atoms and kinetic limitation to reduce thermodynamically-driven segregation during synthesis. It is shown using electron microscopy, X-ray diffraction, and nanoindentation techniques that Ti1-xAlxN (0 less than or equal to x less than or equal to 1) coatings with compositions in the miscibility gap undergo spinodal decomposition during annealing at temperatures between similar to900 degreesC and 1100 degreesC. As a result, coherent cubic-phase nanometer-size domains form that cause an increase in hardness. These intermediate metastable domains transform into their stable phases TiN and hexagonal wurtzite-structure AlN during further thermal treatment. The findings are corroborated by Ab initio calculations of phase stability and molar volume for competing phases. Activation energies for the processes indicate defect-assisted segregation of Ti and Al. It is inferred that the success of Ti1-xAlxN coatings is not only based on its superior oxidation resistance, but also on its ability for self-adaptation to the thermal load applied during cutting by age hardening. The findings and experimental approach have implications also for other ternary and multinary ceramic systems including the group-III nitride alloys.

  • 28.
    Lifvergren-Kaya, Marie
    Linköping University, Department of Thematic Studies.
    Avverkning av nyckelbiotoper: en studie av den teoretiska begreppsdefinitionen och den praktiska hanteringen av nyckelbiotoper2003Independent thesis Advanced level (degree of Magister)Student thesis
    Abstract [sv]

    Detta är en studie av de teoretiska riktlinjerna kring begrepsdefinitionen nyckelbiotop samt den praktiska hanteringen av nyckelbiotoper i skogregionerna Östra Götaland, Dalarna/Gävleborg och Örebro/Värmland. Syftet med studien är att undersöka orsakerna till att nyckelbiotoper avverkas idag. Fokus ligger på om det finns en skillnad mellan den teoretiska begreppsdefinitionen och den praktiska hanteringen av nyckelbiotoper. Undersökningen genomfördes genom enkätfrågor och intervjufrågor till respondenter inom skogsbolag, skogsägarföreningar, stift (skogsbruken) och Skogsvårdsstyrelsen. De övergripande frågeställningarna var om det finns avvikelser mellan beslut och handling i hanteringen av nyckelbiotoper och om definitionen av nyckelbiotoper är förankrad, relevant och fungerande hos dem som planerar och avverkar inom skogssektorn. Enkät - och intervjusvaren från denna studie visar att både skogsbruken och Skogsvårdsstyrelserna anser att definitionen av nyckelbiotoper är förankrad hos dem som planerar och avverkar. Orsakerna till att det avverkas nyckelbiotoper är enligt Skogsvårdsstyrelserna att avverkningarna beror på ekonomiska faktorer vilket inte överensstämmer med skogsbrukens svar. Skogsstyrelsen menade att informationsbrist kunde vara en tänkbar orsak medan skogsbruken var delade i sin synpunkt på denna orsak. Angående definitionens relevans och fungerande i praktiken svarade Skogsvårdstyrelsen övervägande att de tyckte den var fungerande och i skogsbruken var meningarna delade om denna fråga. Av svaren framkom att den teoretiska begreppsdefinitionen ifrågasätts av främst skogsbruken men också av Skogsvårdsstyrelsen då den bland annat är så starkt kopplad till rödlistade arter. Studien visar att det finns mycket som kan och bör åtgärdas i problematiken kring avverkning av nyckelbiotoper och dess orsaker. Det är positivt att studien också visar att samtliga inom skogsbruken samt Skogsvårdsstyrelsens personal anser sig ha möjlighet att påverka inom sin organisation för att förhindra att avverkning av nyckelbiotoper sker i framtiden.

  • 29.
    Dilner, David
    Linköping University, Department of Physics, Chemistry and Biology.
    Behavior of cutting tool coating material Ti1-xAlxN at high pressure and high temperature2009Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The high pressure and high temperature (HPHT) behavior of Ti1-xAlxN coatings on cutting tool inserts have been of interest for this diploma work. A literature study of HPHT techniques as well as measurement methods has been done. A diamond anvil cell (DAC) would be a good device to achieve high pressure and high temperature conditions on small samples. Another way to obtain these conditions would be a cutting test, which has been performed on a Ti1-xAlxN coated cutting tool insert with x = 0.67. Also a cubic press could be used to apply HPHT on a     Ti1-xAlxN sample or a large volume press on a whole cutting tool insert. To measure hardness on thin coatings a nanoindentor could be used, which have been done on heat-treated Ti0.33Al0.67N and TiN samples. X-ray diffraction (XRD) is a suitable method to measure phase composition of a sample and was performed on the cutting tested insert as well as on an untreated reference insert. Three ways to continue this project have been outlined all starting with more comprehensive cutting tests.

  • 30.
    Lenner, Matz
    Linköping University, The Institute of Technology. Linköping University, Department of Mechanical Engineering, Production Engineering.
    Better Workmanship Reduces Hazardous Cutting1999In: IWMS14,1999, 1999Conference paper (Other academic)
  • 31.
    Persson, Bengt
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Bioinformatics.
    Bioinformatics in Membrane Protein Analysis2006In: Structural Genomics on Membrane Proteins / [ed] Lundstrom, Kenneth H., Boca Raton: Taylor&Francis Group , 2006, -400 p.Chapter in book (Other academic)
    Abstract [en]

    While the genomic revolution has quickly led to the deposit of  more than 30,000 structures in the protein data bank (PDB), less than one percent of those contributions represent membrane proteins despite the fact that membrane proteins constitute some 20 percent of all proteins. This discrepancy becomes significantly troublesome when it is coupled with the fact that 60 percent of current drugs are based on targeting this group of proteins, a trend that does not seem likely to reverse.

    Structural Genomics on Membrane Proteinsprovides an excellent overview on novel research in bioinformatics and modeling on membranes, as well as the latest technological developments being employed in expression, purification, and crystallography to obtain high-resolution structures on membrane proteins. This cutting-edge work also explains the difficulties facing researchers—both technical and ethical—that have slowed the process. 

    Structural Genomics on Membrane Proteins provides researchers with an unprecedented look at the novel technologies that will ultimately allow them to conquer the last frontier in structural biology, leading to accelerated breakthroughs in drug discovery.

  • 32.
    Mandenius, Carl-Fredrik
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Biotechnology. Linköping University, The Institute of Technology.
    Björkman, Mats
    Linköping University, Department of Management and Engineering, Assembly technology. Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology.
    Biomechatronic Design in Biotechnology: A Methodology for Development of Biotechnological Products2011Book (Other academic)
    Abstract [en]

    This cutting-edge guide on the fundamentals, theory, and applications of biomechatronic design principles.

    Biomechatronic Design in Biotechnology presents a complete methodology of biomechatronics, an emerging variant of the mechatronics field that marries biology, electronics, and mechanics to create products where biological and biochemical, technical, human, management-and-goal, and information systems are combined and integrated in order to solve a mission that fulfills a human need. A biomechatronic product includes a biological, mechanical, and electronic part. Beginning with an overview of the fundamentals and theory behind biomechatronic technology, this book describes how general engineering design science theory can be applied when designing a technical system where biological species or components are integrated. Some research methods explored include schemes and matrices for analyzing the functionality of the designed products, ranking methods for screening and scoring the best design solutions, and structuring graphical tools for a thorough investigation of the subsystems and sub-functions of products. This insightful guide also:

    • Discusses tools for creating shorter development times, thereby reducing the need for prototype testing and verification
    • Presents case study-like examples of the technology used such as a surface plasmon resonance sensor and a robotic cell culturing system for human embryonic stem cells
    • Provides an interdisciplinary and unifying approach of the many fields of engineering and biotechnology used in biomechatronic design

    By combining designs between traditional electronic and mechanical subsystems and biological systems, this book demonstrates how biotechnology and bioengineering design can utilize and benefit from commonly used design tools-- and benefit humanity itself.

  • 33.
    Mandenius, Carl-Fredrik
    Linköping University, Department of Physics, Chemistry and Biology, Biotechnology. Linköping University, Faculty of Science & Engineering.
    Bioreactors : design, operation and novel applications2016Collection (editor) (Other academic)
    Abstract [en]

    In this expert handbook both the topics and contributors are selected so as to provide an authoritative view of possible applications for this new technology. The result is an up-to-date survey of current challenges and opportunities in the design and operation of bioreactors for high-value products in the biomedical and chemical industries.

    Combining theory and practice, the authors explain such leading-edge technologies as single-use bioreactors, bioreactor simulators, and soft sensor monitoring, and discuss novel applications, such as stem cell production, process development, and multi-product reactors, using case studies from academia as well as from industry. A final section addresses the latest trends, including culture media design and systems biotechnology, which are expected to have an increasing impact on bioreactor design.

    With its focus on cutting-edge technologies and discussions of future developments, this handbook will remain an invaluable reference for many years to come.

  • 34.
    Siddiqui, Farhan
    et al.
    Walden University, Minneapolis, MN, USA .
    Zeadally, Sherali
    University of the District of Columbia, Washington, DC, USA .
    Fowler, Scott
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Boardband Wireless Technologies2013In: Next-Generation Wireless Technologies: 4G and Beyond / [ed] Fourth-generation (4G) or long-term evolution (LTE) technology offers the promise of even smarter computing and multimedia applications which will be available anywhere, at any time. This comprehensive text/reference presents a detailed review of the pioneering research underpinning this emerging technological revolution. The book also examines the various challenges to secure, efficient and cost-effective next-generation wireless networking. Opening with a selection of chapters devoted to the exciting trends in wireless network technology, followed by a section focusing on advanced applications, the text then concludes with an investigation into the future internet systems that will pave the way towards true ubiquitous computing. Topics and features: Presents the latest advances, standards and technical challenges in a broad range of emerging wireless technologies Discusses cooperative and mesh networks, delay tolerant networks, and other next-generation networks such as LTE Examines real-world applications of vehicular communications, broadband wireless technologies, RFID technology, and energy-efficient wireless communications Introduces developments towards the ‘Internet of Things’ from both a communications and a service perspective Discusses the machine-to-machine communication model, important applications of wireless technologies in healthcare, and security issues in state-of-the-art networks This wide-ranging, cutting-edge volume is a ‘must-read’ for all researchers and practitioners involved in wireless communications. Dr. Naveen Chilamkurti is a Senior Lecturer in the Department of Computer Science and Engineering at La Trobe University, Melbourne, Australia. Dr. Sherali Zeadally is an Associate Professor in the Department of Computer Science and Information Technology at the University of the District of Columbia, USA. Dr. Hakima Chaouchi is an Associate Professor at Telecom SudParis, France, London: Springer London, 2013, 71-103 p.Chapter in book (Refereed)
    Abstract [en]

    Fourth-generation (4G) or long-term evolution (LTE) technology offers the promise of even smarter computing and multimedia applications which will be available anywhere, at any time. This comprehensive text/reference presents a detailed review of the pioneering research underpinning this emerging technological revolution. The book also examines the various challenges to secure, efficient and cost-effective next-generation wireless networking. Opening with a selection of chapters devoted to the exciting trends in wireless network technology, followed by a section focusing on advanced applications, the text then concludes with an investigation into the future internet systems that will pave the way towards true ubiquitous computing. Topics and features: Presents the latest advances, standards and technical challenges in a broad range of emerging wireless technologies Discusses cooperative and mesh networks, delay tolerant networks, and other next-generation networks such as LTE Examines real-world applications of vehicular communications, broadband wireless technologies, RFID technology, and energy-efficient wireless communications Introduces developments towards the ‘Internet of Things’ from both a communications and a service perspective Discusses the machine-to-machine communication model, important applications of wireless technologies in healthcare, and security issues in state-of-the-art networks This wide-ranging, cutting-edge volume is a ‘must-read’ for all researchers and practitioners involved in wireless communications. Dr. Naveen Chilamkurti is a Senior Lecturer in the Department of Computer Science and Engineering at La Trobe University, Melbourne, Australia.

  • 35.
    Malmqvist, Erik
    et al.
    Linköping University, The Tema Institute, Technology and Social Change. Linköping University, Faculty of Arts and Sciences.
    Zeiler, KristinLinköping University, The Tema Institute, Technology and Social Change. Linköping University, Faculty of Arts and Sciences.
    Bodily Exchanges, Bioethics and Border Crossing: Perspectives on Giving, Selling and Sharing Bodies2016Collection (editor) (Refereed)
    Abstract [en]

    Medical therapy, research and technology enable us to make our bodies, or parts of them, available to others in an increasing number of ways. This is the case in organ, tissue, egg and sperm donation as well as in surrogate motherhood and clinical research. Bringing together leading scholars working on the ethical, social and cultural aspects of such bodily exchanges, this cutting-edge book develops new ways of understanding them.

    Bodily Exchanges, Bioethics and Border Crossing both probes the established giving and selling frameworks for conceptualising bodily exchanges in medicine, and seeks to develop and examine another, less familiar framework: that of sharing. A framework of sharing can capture practices that involve giving up and giving away part of one’s body, such as organ and tissue donation, and practices that do not, such as surrogacy and research participation. Sharing also recognizes the multiple relationalities that these exchanges can involve and invites inquiry into the context in which they occur. In addition, the book explores the multiple forms of border crossing that bodily exchanges in medicine involve, from the physical boundaries of the body to relational borders – as can happen in surrogacy – to national borders and the range of ethical issues that these various border-crossings can give rise to. 

    Engaging with anthropology, sociology, philosophy, and feminist and postcolonical perspectives, this is an original and timely contribution to contemporary bioethics in a time of increasing globalization. It will be of use to students and researchers from a range of humanities and social science backgrounds as well as medical and other healthcare professionals with an interest in bioethics.

  • 36.
    Bergstedt, Johan
    Linköping University, Department of Physics, Chemistry and Biology, Ecology . Linköping University, The Institute of Technology.
    Boreal vegetation responses to forestry as reflected in field trial and survey data and the quality of cover estimates and presence/absence in vegetation inventory2008Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    This thesis has two main focuses; first, the response of forest ground layer flora on forestry, mainly harvesting and secondly, the quality of the vegetation assessment methods, cover estimates by eye and presence/absence data.

    The effect of harvesting intensity was evaluated with survey data from permanent plots as well as vegetation data from a field trial fourteen years after harvesting. Both data sets confirmed that response of ground layer flora increased with increasing logging intensity. Thereby, indicating that survey data is possible to use in research. From the survey data set, existence of a time lag was evident for several species and also a threshold level was evident in cutting intensity needed to affect a number of species. Logging had a modest, but significant positive effect on the change in species number per plot. Species turnover was influenced by the proportion of Picea abies in the tree canopy; site productivity; and logging intensity. In the field trial scarification had a strong effect that was different from the one created by cutting.

    In plant ecology cover estimate by eye and presence/absence recording are the two most frequent methods used. The methods were evaluated with survey data and a field trial.

    In the first data set vegetation was recorded independently by two observers in 342 permanent 100-m2 plots. Overall, one third of each occurrence was missed by one of the two observers, but with large differences among species. Species occurring at low abundance tended to be frequently overlooked. Observer-explained variance in cover estimates was <10% in 15 of 17 species.

    In the second data set, 10 observers independently estimated cover in sixteen 100-m2 plots in two different vegetation types. The bias connected to observer varied substantially between species. The estimates of missing field and bottom layer had the highest bias, indicating that missing layers are problematic to use in analysis of change. Experience had a surprisingly small impact on the bias connected to observer. Analyses revealed that for the statistical power, cover estimates by eye carries a higher information value than do presence/absence data when distinguishing between vegetation types, differences between observers is negligible, and using more than one observer had little effect.

    List of papers
    1. The impact of logging intensity on field-layer vegetation in Swedish boreal forests
    Open this publication in new window or tab >>The impact of logging intensity on field-layer vegetation in Swedish boreal forests
    2001 (English)In: Forest Ecology and Management, ISSN 0378-1127, Vol. 154, no 1-2, 105-115 p.Article in journal (Refereed) Published
    Abstract [en]

    The relationship between logging intensity and changes in ground cover vegetation was studied in 16 species and groups of species recorded at 10- or 11-year intervals in mature conifer-dominated forests. The 789 plots located in northern and central Sweden had been surveyed by the National Forest Inventory and the National Survey of Forest Soil and Vegetation. Thirty-seven percent of the plots had been subjected to a thinning or clear-cutting between the inventories. A principal components analysis showed that, of the variables considered, logging intensity had the highest explanatory power regarding change in ground cover vegetation between the inventories (the other variables were sum of temperatures, age of stand, timber volume, percentage Pinus sylvestris and site productivity). A multivariate direct gradient analysis technique (Redundancy analysis) showed that the logging intensity significantly affected the change in cover. This analysis also ranked the species in their responsiveness to logging. Epilobium angustifolium, narrow-leaved grasses and broad-leaved grasses, increased most with logging intensity. The response was not linear and only detectable at high logging intensities (>80%). In contrast, Vaccinium myrtillus seemed to decrease linearly with increased logging intensity. There was several years time-lag in the response to logging of E. angustifolium, V. myrtillus and narrow-leaved grasses. Several species and groups of species seemed unaffected by the logging. In sample plots unaffected by logging the cover of most species decreased.

    Keyword
    Clear cut, Community, Cutting, Multivariate analysis, Sweden, Thinning
    Identifiers
    urn:nbn:se:liu:diva-13278 (URN)10.1016/S0378-1127(00)00642-3 (DOI)
    Available from: 2008-05-07 Created: 2008-05-07 Last updated: 2014-10-08
    2. Composition of vegetation after a modified harvesting and propagation method compared with conventional clear-cutting, scarification and planting: evaluation 14 years after logging
    Open this publication in new window or tab >>Composition of vegetation after a modified harvesting and propagation method compared with conventional clear-cutting, scarification and planting: evaluation 14 years after logging
    2008 (English)In: Applied Vegetation Science, ISSN 1402-2001, Vol. 11, no 2, 159-168 p.Article in journal (Refereed) Published
    Abstract [en]

    Question: How does the vegetation of boreal forests respond to harvesting and scarification?

    Location: 650 m a.s.l., central Sweden (61°38' N).

    Methods: The response of boreal forest vegetation to cutting and scarification was studied in a field trial, which consisted of three treatments plus conventional harvesting as a control in a complete block design with four replicates. The cutting was done 14 years prior to vegetation inventory and scarification and planting were conducted the first or second years after cutting.

    Results: The species most abundant at higher cutting intensities were crustose lichens, Cladonia spp., Cladina arbuscula, Polytrichum spp. and pioneer mosses, the grass Deschampsia flexuosa, and the tree Betula pubescens, A few species had substantially lower abundance in treatments with higher cutting intensity, notably Hylocomium splendens and Vaccinium myrtillus. Scarification had a strong effect that was different from the one created by cutting. In scarification treatments, Polytrichum spp. were the only species with high abundance; most species had low abundance, i.e. Barbilophozia lycopodioides, Vaccinium vitis-idaea, Pleurozium schreberi, Carex globularis, Empetrum nigrum, Cladina arbuscula, Sphagnum spp.

    Conclusions: Our results elaborate on the details of the well-known effect of cutting on ground-layer flora, and also give support for the profound and long-lasting effect that soil scarification has on forest vegetation.

    Keyword
    Boreal forest, Cutting intensity, Field trial, Forest understorey, Logging, Propagation, Sweden
    National Category
    Natural Sciences
    Identifiers
    urn:nbn:se:liu:diva-13279 (URN)10.3170/2007-7-18343 (DOI)
    Available from: 2008-05-07 Created: 2008-05-07 Last updated: 2014-10-08
    3. Turnover of ground layer species in Swedish boreal forests and its response to logging
    Open this publication in new window or tab >>Turnover of ground layer species in Swedish boreal forests and its response to logging
    Manuscript (Other academic)
    Identifiers
    urn:nbn:se:liu:diva-13280 (URN)
    Available from: 2008-05-07 Created: 2008-05-07 Last updated: 2010-01-13
    4. Systematic and random variation in vegetation monitoring data
    Open this publication in new window or tab >>Systematic and random variation in vegetation monitoring data
    Show others...
    2008 (English)In: Journal of Vegetation Science, ISSN 1100-9233, Vol. 19, 633-644 p.Article in journal (Refereed) Published
    Abstract [en]

    Question: Detecting species presence in vegetation and making visual assessment of abundances involve a certain amount of skill, and therefore subjectivity. We evaluated the magnitude of the error in data, and its consequences for evaluating temporal trends.

    Location: Swedish forest vegetation.

    Methods: Vegetation data were collected independently by two observers in 342 permanent 100-m2 plots in mature boreal forests. Each plot was visited by one observer from a group of 36 and one of two quality assessment observers. The cover class of 29 taxa was recorded, and presence/absence for an additional 50.

    Results: Overall, one third of each occurrence was missed by one of the two observers, but with large differences among species. There were more missed occurrences at low abundances. Species occurring at low abundance when present tended to be frequently overlooked. Variance component analyses indicated that cover data on 5 of 17 species had a significant observer bias. Observer-explained variance was < 10% in 15 of 17 species.

    Conclusion: The substantial number of missed occurrences suggests poor power in detecting changes based on presence/absence data. The magnitude of observer bias in cover estimates was relatively small, compared with random error, and therefore potentially analytically tractable. Data in this monitoring system could be improved by a more structured working model during field work.

    Place, publisher, year, edition, pages
    Institutionen för fysik, kemi och biologi, 2008
    Keyword
    Forest, Observer error, Permanent plot, Statistical power, Sweden
    National Category
    Natural Sciences
    Identifiers
    urn:nbn:se:liu:diva-11872 (URN)10.3170/2008-8-18423 (DOI)
    Note
    Original publication: Milberg, P., Bergstedt, J., Fridman, J., Odell, G & Westerberg, L., Systematic and random variation in vegetation monitoring data, 2008, Journal of Vegetation Science, (19), 633-644. http://dx.doi.org/10.3170/2008-8-18423. Copyright: Opulus Press, http://www.opuluspress.se/index.phpAvailable from: 2008-05-22 Created: 2008-05-22 Last updated: 2014-10-08
    5. In the eye of the beholder: bias and stochastic variation in cover estimates
    Open this publication in new window or tab >>In the eye of the beholder: bias and stochastic variation in cover estimates
    Manuscript (Other academic)
    Identifiers
    urn:nbn:se:liu:diva-13282 (URN)
    Available from: 2008-05-07 Created: 2008-05-07 Last updated: 2010-01-13
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    Bousquet, J.
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    University Hospital, France; European Innovat Partnership Act and Health Ageing Re, France; INSERM, France; University of Versailles St Quentin En Yvelines, France.
    Bewick, M.
    iQ4U Consultants Ltd, England.
    Cano, A.
    University of Valencia, Spain.
    Eklund, P.
    Umeå University, Sweden; Four Comp Oy, Finland.
    Fico, G.
    University of Politecn Madrid, Spain.
    Goswami, N.
    Medical University of Graz, Austria.
    Guldemond, N. A.
    University of Medical Centre Utrecht, Netherlands.
    Henderson, D.
    European Innovat Partnership Act and Health Ageing, Scotland.
    Hinkema, M. J.
    TNO, Netherlands.
    Liotta, G.
    University of Roma Tor Vergata, Italy.
    Mair, A.
    Scottish Govt Health Department, Scotland.
    Molloy, W.
    University of Coll, Ireland.
    Monaco, A.
    AIFA Agenzia Italiana Farmaco, Italy.
    Monsonis-Paya, I.
    University of Valencia, Spain.
    Nizinska, A.
    University of Lower Silesia, Poland.
    Papadopoulos, H.
    National Centre Science Research, Greece.
    Pavlickova, A.
    European Innovat Partnership Act and Health Ageing, Scotland.
    Pecorelli, S.
    University of Brescia, Italy.
    Prados-Torres, A.
    IIS Aragon Aragon Health Science Institute IACS, Spain.
    Roller-Wirnsberger, R. E.
    Medical University of Graz, Austria.
    Somekh, D.
    European Health Futures Forum, England.
    Vera-Munoz, C.
    University of Politecn Madrid, Spain.
    Visser, F.
    Avisco, Netherlands.
    Farrell, J.
    Department Health Social Serv and Public Safety, North Ireland.
    Malva, J.
    University of Coimbra, Portugal; Ageing Coimbra EIP AHA, Portugal.
    Andersen Ranberg, K.
    Odense University Hospital, Denmark.
    Camuzat, T.
    European Innovat Partnership Act and Health Ageing Re, France; Regional Languedoc Roussillon Midi Pyrenees, France.
    Carriazo, A. M.
    Regional Minist Health Andalusia, Spain.
    Crooks, G.
    European Innovat Partnership Act and Health Ageing, Scotland.
    Gutter, Z.
    University Hospital Olomouc, Czech Republic.
    Iaccarino, G.
    University of Salerno, Italy.
    Manuel De Keenoy, E.
    Kronikgune, Spain.
    Moda, G.
    Regional Piemonte, Italy.
    Rodriguez-Manas, L.
    Getafe University Hospital, Spain.
    Vontetsianos, T.
    Sotiria Hospital, Greece.
    Abreu, C.
    Coimbra School Nursing, Portugal.
    Alonso, J.
    IMIM Institute Hospital Mar Invest Mediques, Spain.
    Alonso-Bouzon, C.
    Getafe University Hospital, Spain.
    Ankri, J.
    INSERM, France; University of Versailles St Quentin En Yvelines, France.
    Arredondo, M. T.
    University of Politecn Madrid, Spain.
    Avolio, F.
    Regional Puglia, Italy.
    Bedbrook, A.
    European Innovat Partnership Act and Health Ageing Re, France.
    Bialoszewski, A. Z.
    Medical University of Warsaw, Poland.
    Blain, H.
    European Innovat Partnership Act and Health Ageing Re, France; Montpellier University Hospital, France; University of Montpellier, France.
    Bourret, R.
    European Innovat Partnership Act and Health Ageing Re, France; Montpellier University Hospital, France.
    Cabrera-Umpierrez, M. F.
    University of Politecn Madrid, Spain; University of Politecn Madrid, Spain.
    Catala, A.
    Technical University of Catalonia, Spain.
    OCaoimh, R.
    University of Coll, Ireland.
    Cesari, M.
    Gerontopole Toulouse, France.
    Chavannes, N. H.
    Leiden University, Netherlands.
    Correia-Da-Sousa, J.
    University of Minho, Portugal.
    Dedeu, T.
    European Regional and Local Health Assoc, Belgium; University of Edinburgh, Scotland.
    Ferrando, M.
    University of Valencia, Spain.
    Ferri, M.
    University of Valencia, Spain.
    Fokkens, W. J.
    Academic Medical Centre, Netherlands.
    Garcia-Lizana, F.
    Institute Health Carlos III, Spain.
    Guerin, O.
    CHRU Nice, France.
    Hellings, P. W.
    Katholieke University of Leuven, Belgium.
    Haahtela, T.
    Helsinki University Hospital, Finland.
    Illario, M.
    Federico II University Hospital Naples, Italy.
    Inzerilli, M. C.
    Community St Egidio Long Live Elderly Program, Italy.
    Lodrup Carlsen, K. C.
    Oslo University Hospital, Norway; University of Oslo, Norway; Oslo University Hospital, Norway; University of Oslo, Norway.
    Kardas, P.
    Medical University of Lodz, Poland.
    Keil, T.
    Charite, Germany; University of Wurzburg, Germany.
    Maggio, M.
    University of Parma, Italy.
    Mendez-Zorrilla, A.
    University of Deusto, Spain.
    Menditto, E.
    University of Naples Federico II, Italy.
    Mercier, J.
    European Innovat Partnership Act and Health Ageing Re, France; University of Montpellier, France.
    Michel, J. P.
    European Union Geriatr Medical Soc, Switzerland; European Geriatr Med, Switzerland.
    Murray, R.
    NHS Scotland, Scotland.
    Nogues, M.
    European Innovat Partnership Act and Health Ageing Re, France; Caisse Assurance Retraite and Sante Travail Langued, France.
    OByrne-Maguire, I.
    AFFINITY, Ireland.
    Pappa, D.
    National Centre Science Research, Greece.
    Parent, A. S.
    AGE Platform Europe, Belgium.
    Pastorino, M.
    University of Politecn Madrid, Spain.
    Robalo-Cordeiro, C.
    Coimbra University Hospital, Portugal.
    Samolinski, B.
    Medical University of Warsaw, Poland.
    Siciliano, P.
    CNR, Italy; INNOVAAL, Italy.
    Teixeira, A. M.
    University of Coimbra, Portugal.
    Tsartara, S. I.
    South East Europe Healthcare Integrated Care and Sr, Greece.
    Valiulis, A.
    Vilnius University, Lithuania; European Academic Paediat EAP UEMS SP, Belgium; European Academic Paediat, Belgium.
    Vandenplas, O.
    Catholic University of Louvain, Belgium.
    Vasankari, T.
    Finnish Lung Assoc, Finland.
    Vellas, B.
    Gerontopole Toulouse, France.
    Vollenbroek-Hutten, M.
    Telemed Grp, Netherlands; University of Twente, Netherlands.
    Wickman, M.
    Soder Sjukhuset, Sweden; Karolinska Institute, Sweden.
    Yorgancioglu, A.
    A Celal Bayar University, Turkey; GARD Execut Comm, Turkey.
    Zuberbier, T.
    Charite, Germany; Global Allergy and Asthma European Network, Germany.
    Barbagallo, M.
    University of Palermo, Italy.
    Canonica, G. W.
    University of Genoa, Italy.
    Klimek, L.
    KLIMEK, Germany.
    Maggi, S.
    CNR Aging Branch, Italy.
    Aberer, W.
    Medical University of Graz, Austria.
    Akdis, C.
    University of Zurich, Switzerland.
    Adcock, I. M.
    Imperial Coll London, England; Royal Brompton and Harefield NHS Trust, England.
    Agache, I.
    Transylvania University of Brasov, Romania.
    Albera, C.
    University of Turin, Italy.
    Alonso-Trujillo, F.
    Andalusian Agency Social Serv and Dependency, Spain.
    Angel Guarcia, M.
    University of Valencia, Spain.
    Annesi-Maesano, I.
    INSERM, France; UPMC, France.
    Apostolo, J.
    Coimbra School Nursing, Portugal.
    Arshad, S. H.
    David Hide Asthma and Allergy Research Centre, England.
    Attalin, V.
    Aviitam, France.
    Avignon, A.
    Montpellier University Hospital, France.
    Bachert, C.
    Ghent University Hospital, Belgium.
    Baroni, I.
    Telbios, Italy.
    Bel, E.
    University of Amsterdam, Netherlands.
    Benson, Mikael
    Linköping University, Department of Clinical and Experimental Medicine, Division of Children's and Women's health. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Allergy Center.
    Bescos, C.
    Phillips Research Institute, Netherlands.
    Blasi, F.
    University of Milan, Italy.
    Barbara, C.
    Portuguese National Programme Resp Disease, Portugal.
    Bergmann, K. C.
    Charite, Germany; Global Allergy and Asthma European Network, Germany.
    Bernard, P. L.
    University of Montpellier, France.
    Bonini, S.
    University of Naples 2, Italy; Italian National Research Council, Italy.
    Bousquet, P. J.
    INSERM, France; UPMC, France.
    Branchini, B.
    University of Valencia, Spain.
    Brightling, C. E.
    University Hospital Leicester NHS Trust, England; University of Leicester, England.
    Bruguiere, V.
    Caisse Assurance Retraite and Sante Travail Langued, France.
    Bunu, C.
    University of Medical and Farm Timisoara, Romania.
    Bush, A.
    Bush A Imperial Coll, England; Royal Brompton Hospital, England.
    Caimmi, D. P.
    Montpellier University Hospital, France.
    Calderon, M. A.
    University of London Imperial Coll Science Technology and Med, England.
    Canovas, G.
    Maire, France.
    Cardona, V.
    Hospital Valle De Hebron, Spain.
    Carlsen, K. H.
    Oslo University Hospital, Norway; University of Oslo, Norway; Oslo University Hospital, Norway; University of Oslo, Norway.
    Cesario, A.
    IRCCS Azienda Osped Santa Maria Nuova, Italy.
    Chkhartishvili, E.
    Grigol Robakidze University, Rep of Georgia.
    Chiron, R.
    Montpellier University Hospital, France.
    Chivato, T.
    University of CEU San Pablo, Spain.
    Chung, K. F.
    University of London Imperial Coll Science Technology and Med, England.
    DAngelantonio, M.
    Health Informat Management SA, Belgium.
    De Carlo, G.
    EFA European Federat Allergy and Airways Disease Patien, Belgium.
    Cholley, D.
    Direct Regional Serv Med, France.
    Chorin, F.
    CIU Sante, France.
    Combe, B.
    University Hospital, France.
    Compas, B.
    Conseil Dep Herault, France.
    Costa, D. J.
    European Innovat Partnership Act and Health Ageing Re, France.
    Costa, E.
    University of Porto, Portugal; University of Porto, Portugal.
    Coste, O.
    Direct Regional Jeunesse Sports and Cohes Sociale, France.
    Coupet, A. -L.
    Caisse Assurance Retraite and Sante Travail Langued, France.
    Crepaldi, G.
    CNR, Italy.
    Custovic, A.
    University of London Imperial Coll Science Technology and Med, England.
    Dahl, R.
    Odense University Hospital, Denmark.
    Dahlen, S. E.
    Karolinska Institute, Sweden.
    Demoly, P.
    INSERM, France; UPMC, France; Montpellier University Hospital, France.
    Devillier, P.
    Suresnes University of Versailles St Quentin, France.
    Didier, A.
    Rangueil Larrey Hospital, France.
    Dinh-Xuan, A. T.
    University of Paris 05, France.
    Djukanovic, R.
    University of Southampton, England; NIHR Southampton Resp Biomed Research Unit, England.
    Dokic, D.
    University of Clin Pulmol and Allergy, Macedonia.
    Du Toit, G.
    Kings Coll London, England.
    Dubakiene, R.
    Vilnius University, Lithuania.
    Dupeyron, A.
    University of Montpellier, France; University of Nimes Hospital, France.
    Emuzyte, R.
    Vilnius University, Lithuania.
    Fiocchi, A.
    Bambino Gesu Childrens Research Hospital, Italy.
    Wagner, A.
    Global Allergy and Asthma Platform GAAPP, Austria.
    Fletcher, M.
    Educ Heatlh, England.
    Fonseca, J.
    Institute CUF Porto Hospital CUF Porto, Portugal; University of Porto, Portugal.
    Fougere, B.
    Gerontopole Toulouse, France.
    Gamkrelidze, A.
    National Centre Disease Control and Public Health Georgia, Rep of Georgia.
    Garces, G.
    University of Valencia, Spain.
    Garcia-Aymeric, J.
    ISGLoBAL, Spain.
    Garcia-Zapirain, B.
    University of Deusto, Spain.
    Gemicioglu, B.
    Istanbul University, Turkey.
    Gouder, C.
    Resident Medical Specialist Medical Mater Dei Hospital, Malta.
    Hellquist-Dahl, B.
    Odense University Hospital, Denmark.
    Hermosilla-Gimeno, I.
    Institute Salud Carlos III, Spain.
    Heve, D.
    Agence Regional Sante, France.
    Holland, C.
    Aston University, England.
    Humbert, M.
    University of Paris 11, France.
    Hyland, M.
    University of Plymouth, England.
    Johnston, S. L.
    University of London Imperial Coll Science Technology and Med, England; MRC and Asthma UK Centre Allerg Mech Asthma, England.
    Just, J.
    University of Paris 06, France.
    Jutel, M.
    Wroclaw Medical University, Poland.
    Kaidashev, I. P.
    Ukrainina Medical Stomatol Acad, Ukraine.
    Khaitov, M.
    National Research Centre, Russia.
    Kalayci, O.
    Hacettepe University, Turkey.
    Kalyoncu, A. F.
    Hacettepe University, Turkey.
    Keijser, W.
    University of Twente, Netherlands; Health Informat Management Spain SL, Spain.
    Kerstjens, H.
    University of Groningen, Netherlands.
    Knezovic, J.
    University of Zagreb, Croatia.
    Kowalski, M.
    Medical University of Lodz, Poland; HARC, Poland.
    Koppelman, G. H.
    University of Groningen, Netherlands.
    Kotska, T.
    Medical University of Lodz, Poland.
    Kovac, M.
    University of Zagreb, Croatia.
    Kull, I.
    Soder Sjukhuset, Sweden; Karolinska Institute, Sweden.
    Kuna, P.
    Barlicki University Hospital, Poland.
    Kvedariene, V.
    Vilnius University, Lithuania.
    Lepore, V.
    AReS Puglia, Italy.
    Macnee, W.
    University of Edinburgh, Scotland.
    Maggio, M.
    University of Parma, Italy.
    Magnan, A.
    University of Nantes, France; Institute Thorax, France.
    Majer, I.
    University of Bratislava, Slovakia.
    Manning, P.
    Bon Secours Hospital, Ireland.
    Marcucci, M.
    University of Milan, Italy; University of Milan, Italy.
    Marti, T.
    Generalitat Catalunya, Spain.
    Masoli, M.
    University of Plymouth, England.
    Melen, E.
    Stockholm County Council, Sweden.
    Miculinic, N.
    Croatian Pulm Soc, Croatia.
    Mihaltan, F.
    National Institute Pneumol M Nasta, Romania.
    Milenkovic, B.
    University of Belgrade, Serbia.
    Millot-Keurinck, J.
    Caisse Assurance Retraite and Sante Travail Langued, France.
    Mlinaric, H.
    University of Zagreb, Croatia.
    Momas, I.
    Paris Descartes University, France; Paris Municipal Department Social Act Childhood and Heatlh, France.
    Montefort, S.
    University of Malta, Malta.
    Morais-Almeida, M.
    Hospital CUF Descobertas, Portugal; Soc Portuguesa Alergol and Imunol Clin, Portugal.
    Moreno-Casbas, T.
    Institute Health Carlos III, Spain.
    Moesges, R.
    University of Cologne, Germany.
    Mullol, J.
    CIBERES, Spain; CIBERES, Spain.
    Nadif, R.
    INSERM, France; University of Versailles St Quentin En Yvelines, France.
    Nalin, M.
    Telbios, Italy.
    Navarro-Pardo, E.
    University of Valencia, Spain; University of Valencia, Spain.
    Nekam, K.
    Hospital Hospitaller Brothers Buda, Hungary.
    Ninot, G.
    University of Montpellier I, France.
    Paccard, D.
    Caisse Assurance Retraite and Sante Travail Langued, France.
    Pais, S.
    University of Algarve, Portugal.
    Palummeri, E.
    Gakkiera Hospital, Italy.
    Panzner, P.
    Charles University of Prague, Czech Republic; Charles University of Prague, Czech Republic.
    Papadopoulos, N. K.
    University of Manchester, England; University of Athens, Greece.
    Papanikolaou, C.
    Laikon Gen Hospital Athens, Greece.
    Passalacqua, G.
    University of Genoa, Italy.
    Pastor, E.
    LETAPE, France; Conseil Regional Ordre Masseurs Kinesitherapeutes, France.
    Perrot, M.
    Regime Social Independants, France.
    Plavec, D.
    University of JJ Strossmayer, Croatia.
    Popov, T. A.
    Alexanders University Hospital, Bulgaria.
    Postma, D. S.
    University of Groningen, Netherlands.
    Price, D.
    Optimum Patient Care, England; University of Aberdeen, Scotland.
    Raffort, N.
    Soc Public Locale Exploitat Balaruc Les Bains, France.
    Reuzeau, J. C.
    Caisse Assurance Retraite and Sante Travail Langued, France.
    Robine, J. M.
    INSERM, France; INSERM, France; Ecole Prat Hautes Etud, France.
    Rodenas, F.
    University of Valencia, Spain.
    Robusto, F.
    AReS Puglia, Italy.
    Roche, N.
    Hop University of Paris, India.
    Romano, A.
    Complesso Integrato Columbus, Italy.
    Romano, V.
    Piedmonte Reference Site, Italy.
    Rosado-Pinto, J.
    Serv Imunoalergol Hospital Luz Lisboa, Portugal.
    Roubille, F.
    European Innovat Partnership Act and Health Ageing Re, France; Montpellier University Hospital, France.
    Ruiz, F.
    University of Valencia, Spain.
    Ryan, D.
    Woodbrook Medical Centre, England; University of Edinburgh, Scotland.
    Salcedo, T.
    University of Politecn Valencia, Spain.
    Schmid-Grendelmeier, P.
    University of Zurich Hospital, Switzerland.
    Schulz, H.
    Helmholtz Zentrum Munchen, Germany.
    Schunemann, H. J.
    University of Freiburg, Germany.
    Serrano, E.
    CHU Rangueil Larrey, France.
    Sheikh, A.
    University of Edinburgh, Scotland.
    Shields, M.
    Queens University of Belfast, North Ireland; Royal Belfast Hospital Sick Children, North Ireland.
    Siafakas, N.
    University Hospital Heraklion, Greece.
    Scichilone, N.
    University of Palermo, Italy.
    Siciliano, P.
    CNR, Italy; INNOVAAL, Italy.
    Skrindo, I.
    Akershun University Hospital, Norway.
    Smit, H. A.
    University of Utrecht, Netherlands.
    Sourdet, S.
    Gerontopole Toulouse, France.
    Sousa-Costa, E.
    University of Porto, Portugal.
    Spranger, O.
    Global Allergy and Asthma Platform GAAPP, Austria.
    Sooronbaev, T.
    Euro Asian Resp Soc, Kyrgyzstan.
    Sruk, V.
    University of Zagreb, Croatia.
    Sterk, P. J.
    University of Amsterdam, Netherlands.
    Todo-Bom, A.
    University of Coimbra, Portugal.
    Touchon, J.
    University Hospital Montpellier, France.
    Tramontano, D.
    University of Naples Federico II, Italy; GENS Fdn, Italy.
    Triggiani, M.
    University of Salerno, Italy.
    Tsartara, S. I.
    South East Europe Healthcare Integrated Care and Sr, Greece.
    Valero, A. L.
    IDIBAPS, Spain.
    Valovirta, E.
    University of Turku, Finland.
    Van Ganse, E.
    University of Lyon 1, France.
    Van Hage, M.
    Karolinska Institute and University Hospital, Sweden.
    Van den Berge, M.
    University of Groningen, Netherlands.
    Vandenplas, O.
    Catholic University of Louvain, Belgium.
    Ventura, M. T.
    University of Bari, Italy.
    Vergara, I.
    VERGARA Itziar Kronikgune, Spain.
    Vezzani, G.
    Research Hospital, Italy; Regional Agency Health and Social Care, Italy.
    Vidal, D.
    University of Valencia, Spain.
    Viegi, G.
    CNR, Italy.
    Wagemann, M.
    University of Klinikum Dusseldorf, Germany.
    Whalley, B.
    University of Plymouth, England.
    Wickman, M.
    Soder Sjukhuset, Sweden; Karolinska Institute, Sweden.
    Wilson, N.
    North England EU Health Partnership, Australia.
    Yiallouros, P. K.
    Cyprus University of Technology, Cyprus; Hospital Archbishop Makarios III, Cyprus.
    Zagar, M.
    University of Zagreb, Croatia.
    Zaidi, A.
    University of Southampton, England.
    Zidarn, M.
    University of Clin Resp and Allerg Disease, Slovenia.
    Hoogerwerf, E. J.
    Funka, Sweden.
    Usero, J.
    Funka, Sweden.
    Zuffada, R.
    Funka, Sweden.
    Senn, A.
    European Commiss, Belgium.
    De Oliveira-Alves, B.
    European Commiss, Belgium.
    BUILDING BRIDGES FOR INNOVATION IN AGEING: SYNERGIES BETWEEN ACTION GROUPS OF THE EIP ON AHA2017In: The Journal of Nutrition, Health & Aging, ISSN 1279-7707, E-ISSN 1760-4788, Vol. 21, no 1, 92-104 p.Article in journal (Refereed)
    Abstract [en]

    The Strategic Implementation Plan of the European Innovation Partnership on Active and Healthy Ageing (EIP on AHA) proposed six Action Groups. After almost three years of activity, many achievements have been obtained through commitments or collaborative work of the Action Groups. However, they have often worked in silos and, consequently, synergies between Action Groups have been proposed to strengthen the triple win of the EIP on AHA. The paper presents the methodology and current status of the Task Force on EIP on AHA synergies. Synergies are in line with the Action Groups new Renovated Action Plan (2016-2018) to ensure that their future objectives are coherent and fully connected. The outcomes and impact of synergies are using the Monitoring and Assessment Framework for the EIP on AHA (MAFEIP). Eight proposals for synergies have been approved by the Task Force: Five cross-cutting synergies which can be used for all current and future synergies as they consider overarching domains (appropriate polypharmacy, citizen empowerment, teaching and coaching on AHA, deployment of synergies to EU regions, Responsible Research and Innovation), and three cross-cutting synergies focussing on current Action Group activities (falls, frailty, integrated care and chronic respiratory diseases).

  • 38.
    Jover Casanovas, Elena
    Linköping University, Department of Management and Engineering, Carl Malmsten - furniture studies.
    Can laser cutting be an alternative technique for marquetry completion in furniture conservation?2011Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [en]

    This study describes experiments and findings of an investigation to evaluate the use of laser cutting as an alternative to traditional sawing techniques in marquetry completion conservation.

    Experiments on veneer from 11 different species of wood, covering ring porous, semi-diffuse/-ring porous and diffuse porous woods, were carried out and examined. The optimal cutting metrics with respect to speed, power and frequency for the types of wood were determined. The most important ethical question for a conservator is to be able to preserve as much as original material as possible. The results of this project show that the use of a laser cutting machine is indeed a suitable solution to produce replacement veneer for marquetry works in furniture conservation with respect to quality and time. Especially when it comes to the precision in the shape of the replacement piece, laser cutting is superior to hand sawing. This makes laser cutting an interesting option and reduces the need for expert skills in hand sawing in order to perform very detailed completion work. It also reduces the need of invasive work on the original marquetry to accommodate the replacement piece.

    The findings are general for all of the examined types of wood. On the negative side, the laser cutting machine requires a relatively big initial investment, making it difficult to say if it is really a cost-effective method of cutting replacement veneer pieces.

  • 39.
    Norrlander, Jens
    et al.
    Linköping University, Department of Management and Economics.
    Andersson Anell, Per
    Linköping University, Department of Management and Economics.
    Can Micro Credits Contribute To Poverty Alleviation?: A study of female entrepreneurs in Vietnam.2001Independent thesis Advanced level (degree of Magister)Student thesis
    Abstract [en]

    Introduction: Poverty is today a global problem which is getting more and more attention. Organisations as UNDP, OECD and World Bank have a common target of cutting poverty in half by year 2015. But if this target is going to be feasible it is important to understand poverty. Nobel Prize winner Amartya Sen argues that standard of living should be expressed in quality of life not in terms of quantity of goods and other economic factors. Sen has developed theories concerning poverty that is commonly used in today debate. One way to diminish poverty is microfinance. Microfinance is small loans given to poor people as a way for them to start or develop a business of some kind. Microfinance programs often combine the loans with education and social activities. Aim: Investigate if microfinance can contribute to permanent poverty alleviation, develop a model and apply it in rural Vietnam. The following questions will help to achieve our aim: - How do microfinance effect poor women in rural Vietnam? - What happens if one applies Amartya Sen's theories of poverty in rural Vietnam?

    Results: Microfinance is a good tool in the struggle to diminishing poverty. We found many examples where microfinance had improved the women’s life in different areas. But to make the microfinance even more effective it is important it is effective education and right members participating. Under ideal circumstances the process of microfinance work as in the NORAN-model, however in reality it is not so easy. But if you are aware of the problems and try to avoid them, microfinance can help many women. Thus our conclusion is that microfinance certainly can and already do contribute to permanent poverty alleviation.

  • 40.
    Ittekot, Venu
    et al.
    University of Bremen.
    Humborg, Christoph
    SU.
    Rahm, Lars
    Linköping University, The Tema Institute, Department of Water and Environmental Studies. Linköping University, Faculty of Arts and Sciences.
    An, Tac
    Viet Nam.
    Carbon Silicon Interactions.2003In: Interactions of the Major Biogeochemical Cycles: Global Change and Human Impacts / [ed] Jerry M. Melillo, Christopher B. Field, Bedrich Moldan, New York: Island Press , 2003, 1, 311-336 p.Chapter in book (Other academic)
    Abstract [en]

    The circulation and interactions of major elements such as carbon, nitrogen, phosphorus, sulphur, oxygen, and hydrogen are critical for the maintenance of the earth's ecosystems. Human activities including agriculture, industry, and urbanization alter element interactions and contribute to major environmental problems ranging from climate change and depletion of the ozone layer to acidification of soils to the destruction of coral reefs.

    Interactions of the Major Biogeochemical Cyclesis a new scientific assessment of element interactions in the biosphere. It provides an up-to-date review of biogeochemistry and its effects on earth's systems, with leading experts in biogeochemical cycling in atmospheric, land, freshwater, and marine environments offering chapters that summarize and synthesize information in each discipline.

    The book opens with chapters on cross-cutting issues that have significance in understanding global change effects and their potential management. These chapters address:

    * trends in element interactions in response to global change

    • the effects of natural disturbances
    • new approaches and methods for advancing our understanding of element interactions
    • the potential for managing element interactions to address major environmental issues
  • 41. Geusens, B
    et al.
    Mollet, I
    Anderson, Chris D
    Linköping University, Department of Clinical and Experimental Medicine, Dermatology and Venerology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Centre, Department of Dermatology and Venerology in Östergötland.
    Terras, S
    Roberts, M S
    Lambert, J
    Changes in skin immunity with age and disease2010In: The Innate Immune System of Skin and Oral Mucosa: Properties and Impact in Pharmaceutics, Cosmetics and Personal Care Products / [ed] Nava Dayan and Philip Wertz, Wiley , 2010Chapter in book (Other academic)
    Abstract [en]

    An in-depth look at cutting-edge research on the body's innate immune system

    Innate immunity is the body's first line of protection against potential microbial, viral, and environmental attacks, and the skin and oral mucosa are two of the most powerful barriers that which we rely on to stay well. The definitive book on the subject, Innate Immune System of Skin and Oral Mucosa: Properties and Impact in Pharmaceutics, Cosmetics, and Personal Care Products provides a comprehensive overview of these systems, including coverage of antimicrobial peptides and lipids and microbial challenges and stressors that can influence innate immunity.

    Designed to help experts and newcomers alike in fields like dermatology, oral pathology, cosmetics, personal care, and pharmaceuticals, the book is filled with suggestions to assist research and development. Looking at the many challenges facing the innate immune system, including the impact of topically applied skin products and medications, Innate Immune System of Skin and Oral Mucosa paves the way for next generation treatment avenues, preventative approaches, and drug development.

  • 42.
    Blixt, Torbjörn
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Bergman, Karl-Olof
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Milberg, Per
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Westerberg, Lars
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Jonason, Dennis
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Clear-cuts in production forests: From matrix to neo-habitat forbutterflies2015In: Acta Oecologica, ISSN 1146-609X, E-ISSN 1873-6238, Vol. 69, 71-77 p.Article in journal (Refereed)
    Abstract [en]

    Butterfly conservation in Europe is mainly focused on well-defined grassland habitat patches. Such anapproach ignores the impact of the surrounding landscape, which may contain complementary resourcesand facilitate dispersal. Here, we investigated butterfly species richness and abundance in a habitatnormally regarded as unsuitable matrix: production forestry clear-cuts. Butterflies were recorded in 48clear-cuts in southern Sweden differing with regards to the time since clear-cutting and land-use history(meadow or forest based on historical maps from the 1870s). All clear-cuts had been managed as productionforests for at least 80e120 years. A total of 39 species were found in clear-cuts of both land-usehistories, but clear-cuts with a history as meadow had on average 34% higher species richness and 19%higher abundance than did clear-cuts with a history as forest. No effect of the time since clear-cuttingwas found, irrespective of land-use history, which was likely due to the narrow timespan sampled (<8years). The absence of temporal effect suggests that clear-cuts may provide butterflies with valuableresources for 10e15 years. Assuming a 100 year forest rotational cycle, this means that 10e15% of thetotal forested area are made up by clear-cuts valuable to butterflies, which corresponds to an area aboutfour times as large as that of species-rich semi-natural grasslands. The study illustrates the importance ofconsidering land-use legacies in ecological research and question the landscape-ecological view thatclear-cuts make up an unsuitable matrix for butterflies. Moreover, forest conservation management withspecial attention to land-use history may increase the quality of the landscape, thus facilitating butterflymetapopulation persistence. Given their large area and assets of nectar and host plant resources, clearcutsmust be considered as a butterfly habitat in its own right. Being a man-made environment withshort history, we might call it a neo-habitat.

  • 43.
    Bäckman, Jenny
    et al.
    Linköping University, Department of Physics, Chemistry and Biology.
    Kasimir Klemedtsson, Åsa
    Klemedtsson, Leif
    Lindgren, Per-Eric
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Molecular and Clinical Medicine, Medical Microbiology.
    Clear-cutting affects the ammonia-oxidising community differently in limed and non-limed coniferous forest soils2004In: Biology and Fertility of Soils, ISSN 0178-2762, Vol. 40, no 4, 260-267 p.Article in journal (Refereed)
    Abstract [en]

    The effects of clear-cutting on the ammonia-oxidising bacterial community were studied in the soil of limed and non-limed spruce forest plots located in the central part of southern Sweden. The communities were studied using denaturing gradient gel electrophoresis (DGGE) profiling after polymerase chain reaction (PCR) amplification from total DNA with primers reported to be specific for β-subgroup ammonia-oxidising bacteria. The bands on the DGGE were sequenced and each unique sequence was interpreted as representing one ammonia-oxidising population. The relative abundance of each population was determined by measuring the fluorescence of the respective DGGE bands. In both limed and non-limed soil, the same two Nitrosospira populations were found, one belonging to cluster 2 (NScl2) and one to cluster 4 (NScl4). However, while NScl4 first appeared a year after the clear-cutting in the non-limed plot, it was present both before and after the cutting in the limed plot. Irrespective of previous liming, clear-cutting caused a shift in the ammonia-oxidiser community, from dominance by the NScl2 population to a community with approximately equal relative abundance of NScl2 and NScl4. In both plots the total size of the community increased after clear-cutting (based on increased DGGE band intensity), most likely due to increased NH4+ availability, but the growth response was faster in the limed plot. Hence, the prior liming increased the responsiveness of the ammonia-oxidisers to the changes caused by cutting. This is the first study to report the effects of clear-cutting on the ammonia-oxidising community, and the results show a clear correlation between increased potential nitrification and a shift in the ammonia-oxidiser community.

  • 44.
    Skoglund, Björn
    Linköping University, Department of Electrical Engineering.
    Code profiling as a design tool for application specific instruction sets2007Independent thesis Basic level (professional degree), 20 points / 30 hpStudent thesis
    Abstract [en]

    As the embedded devices has become more and more generalized and as their product cycles keeps shrinking the field has opened up for the Application Specific Instruction set Processor. A mix between the classic generalized microcontroller and the specialized ASIC the ASIP keeps a set of general processing instructions for executing embedded software but combines that with a set of heavily specialized instructions for speeding up the data intense application core algorithms. One important aspect of the ASIP design flow

    research is cutting design time and cost. One way of that is automation of the instruction set design. In order to do so a process is needed where the algorithm to be ASIPed is analyzed and critical operations are found and exposed so that they can be implemented in special hardware. This process is called profiling. This thesis describes an implementation of a fine grained source code profiler for use in an ASIP design flow. The profiler software is based on a static-dynamic workflow where data is assembled from both static

    analysis and dynamic execution of the program and then analyzed together in an specially made analysis software.

  • 45.
    Rönnberg, Jerker
    Linköping University, Faculty of Arts and Sciences. Linköping University, Department of Behavioural Sciences, The Swedish Institute for Disability Research.
    Cognitive and neuroscience perspectives on speech and sign processing: Evidence from persons with deafness, hearing impairment, and normal hearing2006In: Progress in psychological science around the world: proceedings of the 28th International Congress of Psychology. 1, Neural, cognitive and developmental issues / [ed] Gery d'Ydewalle, Houcan Zhang, Hsuan-Chih Chen, Kan Zhang, London: Psychology Press , 2006, 383-399 p.Chapter in book (Other academic)
    Abstract [en]

    Progress in Psychological Science around the World, Volumes 1 and 2, present the main contributions from the 28th International Congress of Psychology, held in Beijing in 2004. These expert contributions include the Nobel laureate address, the Presidential address, and the Keynote and State-of-the-Art lectures. They are written by international leaders in psychology from 25 countries and regions around the world. The authors present a variety of approaches and perspectives that reflect cutting-edge advances in psychological science.

  • 46.
    Safavi, Edris
    Linköping University, Department of Management and Engineering, Machine Design. Linköping University, Faculty of Science & Engineering.
    Collaborative Multidisciplinary Design Optimization for Conceptual Design of Complex Products2016Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    MULTIDESCIPLINARY design optimization (MDO) has developed in theory andpractice during the last three decades with the aim of optimizing complexproducts as well as cutting costs and product development time. Despite thisdevelopment, the implementation of such a method in industry is still a challenge andmany complex products suffer time and cost overruns.

    Employing higher fidelity models (HFMs) in conceptual design, one of the early and most important phases in the design process, can play an important role in increasing the knowledge base regarding the concept under evaluation. However, design space in the presence of HFMs could significantly be expanded. MDO has proven to be an important tool for searching the design space and finding optimal solutions. This leads to a reduction in the number of design iterations later in the design process, with wiser and more robust decisions made early in the design process to rely on.

    In complex products, different systems from a multitude of engineering disciplines have to work tightly together. This stresses the importance of evolving various domain experts in the design process to improve the design from diverse engineering perspectives. Involving more engineers in the design process early on raises the challenges of collaboration, known to be an important barrier to MDO implementation in industry. Another barrier is the unavailability and lack of MDO experts in industry; those who understand the MDO process and know the implementation tasks involved.

    In an endeavor to address the mentioned implementation challenges, a novel collaborative multidisciplinary design optimization (CMDO) framework is defined in order to be applied in the conceptual design phase. CMDO provides a platform where many engineers team up to increase the likelihood of more accurate decisions being taken early on. The structured way to define the engineering responsibilities and tasks involved in MDO helps to facilitate the implementation process.

    It will be further elaborated that educating active engineers with MDO knowledge is an expensive and time-consuming process for industries. Therefore, a guideline for CMDO implementation in conceptual design is proposed in this thesis that can be easily followed by design engineers with limited prior knowledge in MDO. The performance of the framework is evaluated in a number of case studies, including applications such as aircraft design and the design of a tidal water power plant, and by engineers in  industry and student groups in academia.

    List of papers
    1. A Collaborative Tool for Conceptual Aircraft Systems Design
    Open this publication in new window or tab >>A Collaborative Tool for Conceptual Aircraft Systems Design
    2012 (English)In: Guidance, Navigation, and Control and Co-located Conferences: AIAA Modeling and Simulation Technologies Conference / [ed] The American Institute of Aeronautics and Astronautics, Reston, VA, USA: American Institute of Aeronautics and Astronautics, 2012, 1-10 p.Conference paper, Published paper (Refereed)
    Abstract [en]

    Advances in recent years has brought forth many feasible technologies which oer signif-icant design advantages over the traditional aircraft vehicle ight systems. These advanceshave brought about a need for the aircraft conceptual engineers to evaluate these newtechnologies so as to realize a realistic and optimized architecture which fulls all criti-cal disciplinary requirements. To evaluate these systems, it is necessary to use models ofcomplexity which are a degree higher than what is being used today. Quick developmentand evaluation of these models can be a hard task for an engineer to achieve consideringthe multidisciplinary nature of the systems. A collaborative eort in model developmentbetween various department is needed if the conceptual design is to be completed withinthe time frame. To facilitate a collaborative conceptual design a research project was for-malized at Linkoping university, which has led to the development of a tool named CAVE(Conceptual Aircraft Vehicle Engineering) which can be used to evaluate the architectureof aircraft systems. In this paper, CAVE as a conceptual design tool will be presented.

    Place, publisher, year, edition, pages
    Reston, VA, USA: American Institute of Aeronautics and Astronautics, 2012
    Keyword
    Aircraft Conceptual Design
    National Category
    Aerospace Engineering
    Identifiers
    urn:nbn:se:liu:diva-86275 (URN)10.2514/6.2012-4716 (DOI)978-1-62410-183-0 (ISBN)
    Conference
    AIAA Modeling and Simulation Technologies Conference 13-16 August 2012, Minneapolis, Minnesota
    Available from: 2012-12-18 Created: 2012-12-12 Last updated: 2016-10-06Bibliographically approved
    2. Collaborative multidisciplinary design optimization: A framework applied on aircraft conceptual system design
    Open this publication in new window or tab >>Collaborative multidisciplinary design optimization: A framework applied on aircraft conceptual system design
    2015 (English)In: Concurrent Engineering - Research and Applications, ISSN 1063-293X, E-ISSN 1531-2003, Vol. 23, no 3, 236-249 p.Article in journal (Refereed) Published
    Abstract [en]

    In a product development process, it is crucial to understand and evaluate multiple and synergic aspects of systems such as performance, cost, reliability, and safety. These aspects are mainly considered during later stages of the design process. However, in order to improve the foundations for decision-making, this article presents methods that are intended to increase the engineering knowledge in the early design phases. In complex products, different systems from a multitude of engineering disciplines have to work tightly together. Collaborative design is described as a process where a product is designed through the collective and joint efforts of domain experts. A collaborative multidisciplinary design optimization process is therefore proposed in the conceptual design phase in order to increase the likelihood of more accurate decisions being taken early on. The performance of the presented framework is demonstrated in an industrial application to design aircraft systems in the conceptual phase.

    Place, publisher, year, edition, pages
    Sage Publications, 2015
    Keyword
    conceptual design; collaborative design; aircraft system design; multidisciplinary design optimization
    National Category
    Mechanical Engineering
    Identifiers
    urn:nbn:se:liu:diva-122539 (URN)10.1177/1063293X15587020 (DOI)000362993200005 ()
    Note

    Funding Agencies|VINNOVA (Swedens innovation agency) through the IMPOz project [2013-03758]

    Available from: 2015-11-09 Created: 2015-11-06 Last updated: 2016-10-06
    3. Implementation of collaborative multidisciplinary design optimization for conceptual design of a complex engineering product
    Open this publication in new window or tab >>Implementation of collaborative multidisciplinary design optimization for conceptual design of a complex engineering product
    Show others...
    2016 (English)In: Concurrent Engineering - Research and Applications, ISSN 1063-293X, E-ISSN 1531-2003, Vol. 24, no 3, 251-265 p.Article in journal (Refereed) Published
    Abstract [en]

    This study investigates the performance of the collaborative multidisciplinary design optimization framework and how it facilitates the knowledge integration process. The framework is used to design and optimize an innovative concept of a tidal water power plant. The case study helps to highlight the challenges that may occur during implementation. The result is presented as a modified framework with less implementation difficulties. The improved framework shows significant reduction in design time and improvement in collaborative design optimization for a design team. The geometry of the product is optimized to minimize weight and maximize the power generated by the turbine with respect to some mechanical constraints.

    Place, publisher, year, edition, pages
    Sage Publications, 2016
    National Category
    Production Engineering, Human Work Science and Ergonomics Human Computer Interaction Fluid Mechanics and Acoustics Interaction Technologies Aerospace Engineering Design
    Identifiers
    urn:nbn:se:liu:diva-131790 (URN)10.1177/1063293X16661224 (DOI)000382850200005 ()
    Note

    Funding agencies: VINNOVA (Swedens innovation agency) through IMPOz project [2013-03758]

    Available from: 2016-10-06 Created: 2016-10-06 Last updated: 2016-10-13Bibliographically approved
    4. Rapid Concept Realization for Conceptual Design of Modular Industrial Robots
    Open this publication in new window or tab >>Rapid Concept Realization for Conceptual Design of Modular Industrial Robots
    2010 (English)In: Proceedings of NordDesign 2010, the 8th International NordDesign Conference, Göteborg, Sweden, 25.-27.08. 2010 / [ed] Andreas Dagman and Rikard Söderberg, 2010, 375-384 p.Conference paper, Published paper (Refereed)
    Abstract [en]

    When conducting design on novel mechatronic products, it can be valuable to test and evaluate the performance and properties of the concepts throughout the design process by producing them as downscaled prototypes, see Jouannet et al. [1]. This is especially true when the product is of unconventional design and the designer can get increased confidence of the proposed concept by testing it as a sub scaled version. Nonetheless, the process of realization of new concept should be done in a rapid fashion in order not to halt the design process and simultaneously increasing explicit knowledge about the concept. A case study will be illustrated which demonstrates how fully automated design and construction of downscaled prototypes is performed.

    Keyword
    Automated design, multidisciplinary design, industrial robots
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-62606 (URN)978-91-633-7063-2 (Vol. 1) (ISBN)978-91-633-7064-9 (Vol. 2) (ISBN)
    Conference
    8th International NordDesign Conference, Göteborg, Sweden, August 25-27, Göteborg, Sweden
    Available from: 2010-11-30 Created: 2010-11-30 Last updated: 2016-10-06Bibliographically approved
  • 47.
    Alling, Björn
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Theoretical Physics .
    Marten, Tobias
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Theoretical Physics .
    Abrikosov, Igor
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Theoretical Physics .
    Karimi, A.
    Swiss Federal Institute of Technology Lausanne, Switzerland.
    Comparison of thermodynamic properties of cubic Cr 1-x Al x N and Ti 1-x Al x N from first-principles calculations2007In: Journal of Applied Physics, ISSN 0021-8979, Vol. 102, no 044314Article in journal (Refereed)
    Abstract [en]

    In order to investigate the stability of the cubic phase of Cr1−xAlxN at high AlN content, first principles calculations of magnetic properties, lattice parameters, electronic structure, and mixing enthalpies of the system were performed. The mixing enthalpy was calculated on a fine concentration mesh to make possible the accurate determination of its second concentration derivative. The results are compared to calculations performed for the related compound Ti1−xAlxN and with experiments. The mixing enthalpy is discussed in the context of isostructural spinodal decomposition. It is shown that the magnetism is the key to understand the difference between the Cr- and Ti-containing systems. Cr1−xAlxN turns out to be more stable against spinodal decomposition than Ti1−xAlxN, especially for AlN-rich samples which are of interest in cutting tools applications.

  • 48.
    Bergstedt, Johan
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Ecology . Linköping University, The Institute of Technology.
    Hagner, M.
    Milberg, P.
    Linköping University, Department of Physics, Chemistry and Biology, Ecology . Linköping University, The Institute of Technology.
    Composition of vegetation after a modified harvesting and propagation method compared with conventional clear-cutting, scarification and planting: evaluation 14 years after logging2008In: Applied Vegetation Science, ISSN 1402-2001, Vol. 11, no 2, 159-168 p.Article in journal (Refereed)
    Abstract [en]

    Question: How does the vegetation of boreal forests respond to harvesting and scarification?

    Location: 650 m a.s.l., central Sweden (61°38' N).

    Methods: The response of boreal forest vegetation to cutting and scarification was studied in a field trial, which consisted of three treatments plus conventional harvesting as a control in a complete block design with four replicates. The cutting was done 14 years prior to vegetation inventory and scarification and planting were conducted the first or second years after cutting.

    Results: The species most abundant at higher cutting intensities were crustose lichens, Cladonia spp., Cladina arbuscula, Polytrichum spp. and pioneer mosses, the grass Deschampsia flexuosa, and the tree Betula pubescens, A few species had substantially lower abundance in treatments with higher cutting intensity, notably Hylocomium splendens and Vaccinium myrtillus. Scarification had a strong effect that was different from the one created by cutting. In scarification treatments, Polytrichum spp. were the only species with high abundance; most species had low abundance, i.e. Barbilophozia lycopodioides, Vaccinium vitis-idaea, Pleurozium schreberi, Carex globularis, Empetrum nigrum, Cladina arbuscula, Sphagnum spp.

    Conclusions: Our results elaborate on the details of the well-known effect of cutting on ground-layer flora, and also give support for the profound and long-lasting effect that soil scarification has on forest vegetation.

  • 49.
    Sidenvall, Vincent
    Linköping University, Department of Management and Engineering, Machine Design.
    Conceptual Design of AM Container for “3D-Printer Cloud” Close to Customer Site: Plant-in-the-box2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This is a master thesis about the Plant-in-the-box concept. The master thesis is to develop initial requirements and an initial layout to further investigate the concept. Plant-in-the-box in combination with the Vertical Workshop concept are a part of the “Digitalization @ PS”–Initiative, at Siemens, that started in October 2015 and forms a way of portable and flexible workshops. Plant-in-the-box is based on the idea to have a Additive Manufacturing, AM, machine with all its surrounding systems and equipment in a container which can easily be shipped to a new destination if desired. This AM container can then be combined with other containers containing anything from machinery for cutting processing to desktop stations and equipment for climate control. The set of containers are organized in a Vertical Workshop, where the containers can be slipped into a rack which supports the multi-storage workshop with accessibility and the necessary media. The Vertical Workshop can easily be deployed close to customer and as a part of a 3DPrinter Cloud provide a network of  production units placed on strategic locations.

  • 50.
    Edvardsson, Jon
    Linköping University, Department of Mechanical Engineering, Fluid and Mechanical Engineering Systems. Linköping University, The Institute of Technology.
    Contributions to program- and specification-based test data generation2002Licentiate thesis, monograph (Other academic)
    Abstract [en]

    Software testing is complex and time consuming. One way to reduce testing effort is to automatically generate test data. In the first part of this thesis we consider a framework by Gupta et al. for generating tests from programs. In short, their approach consists of a branch predicate collector, which derives a system of linear inequalities representing an approximation of the branch predicates for a given path in the program. This system is solved using their constraint solver called the Unified Numerical Approach (UNA). In this thesis we show that in contrast to traditional optimization methods the UNA is not bounded by the size of the solved system. Instead it depends on how input is composed. That is, even for very simple systems consisting of one variable we can easily get more than a thousand iterations. We will also give a formal proof that UNA does not always find a mixed integer solution when there is one. Finally, we suggest using some traditional optimization method instead, like the simplex method in combination with branch-and-bound and/or a cutting-plane algorithm as a constraint solver.

    In the second part we study a specification-based approach for generation of software tests developed by Meudec. Briefly, tests are generated by an automatic partitioning strategy based on partition rules. An important step in the process is to reduce the number of generated subdomains and find a minimal partition. However, we have found that Meudec-s algorithm does not always produce a minimal partition. In this work we present an alternative solution to the minimal partition problem by formulating it as an integer programming problem. By doing so, we can use well known optimization methods to solve this problem.

    A more efficient way to derive a minimal partition would be using Meudec's conjectured two-step reduction approach: vertex merging and minimal path coverage. Failing to find a general solution to either of the steps, Meudec abandoned this approach. How-ever, in this work we present an algorithm based on partial expansion of the partition graph for solving the first step. Furthermore, our work in partial expansion has led to new results: we have determined an upper bound on the size of a minimal partition. In turn, this has led to a stronger definition of our current minimal partition algorithm. In some special cases we can also determine lower bounds. 

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