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  • 301.
    Eriksson, Anders
    et al.
    Linköping University, Department of Mechanical Engineering.
    Knutsson, Jonas
    Linköping University, Department of Mechanical Engineering.
    Konstruktion av handhållet lyftverktyg2005Independent thesis Basic level (degree of Bachelor), 10 points / 15 hpStudent thesis
    Abstract [sv]

    Tyngdpunkten i arbetet ligger på framtagningen av ett handhållet verktyg för hantering av papphylsor vid Stora Ensos pappersbruk i Grycksbo. Framtagningen av verktyget följer er¬hållen kunskap inom konstruktionsmetodik och syftar till att förändra dagens arbetssätt och därmed minimera risken för arbetsskador vid den manuella hanteringen av hylsorna. Studier av alternativa lösningar, som skulle kunna skapa gynnsammare förutsättningar för att uppnå målet, har också genomförts. Resultatet, med rekommendationer och underlag för fortsatt arbete, som överlämnas till företaget innehåller följande:

    - CAD-ritningar i form av en 3D-modell över framtaget verktyg.

    - Förslag på modifiering av hylshäck för en effektivare hantering.

    - Förslag på grundläggande förändringar som idag enbart tillämpas i viss utsträckning.

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  • 302.
    Eriksson, Björn
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Mechanical Engineering, Fluid and Mechanical Engineering Systems.
    Andersson, Bo
    Linköping University, The Institute of Technology. Linköping University, Department of Mechanical Engineering, Fluid and Mechanical Engineering Systems.
    Palmberg, Jan-Ove
    Linköping University, The Institute of Technology. Linköping University, Department of Mechanical Engineering, Fluid and Mechanical Engineering Systems.
    The Dynamic Performance of a Pilot Stage in the Poppet Type Hydraulic Flow Amplifier2008In: The 51st NCFP Technical Conference,2008, Proceedings of the 51st NCFP Technical Conference: Omnipress , 2008, p. 659-Conference paper (Refereed)
    Abstract [en]

    This paper examines the dynamic properties of the pilot stage in a poppet type two-stage flow control valve of the -Valvistor- type. The particular valve studied is a screw-in Valvistor valve of NG16 size. There are several benefits to this valve type: it has a high closed loop bandwidth and the design allows big flow capacities. An attractive feature of this two-stage valve is that the pilot flow contributes to the total flow giving higher steady state flow efficiency. The dynamic characteristics of the main stage were discussed in an earlier paper. In this paper the aim is to study the influence of the pilot stage of the valve. The bandwidth of this type of valve is often unexpected low. Due to the high bandwidth of the Valvistor element the pilot dynamics is often dominating. In this paper it is shown by measurements the influence of different parts in the pilot valve that limits its bandwidth. Flow forces are used in this valve to compensate the pressure dependency in the flow. It is a common way of design in so called pressure compensated valves. It is discussed in the paper how this flow forces influences the dynamic properties of the pilot valve. The mentioned flow forces interact together with the mechanical spring in the pilot valve. Although the studied valve is just one of many variants of the Valvistor principle, we will investigate it closely due to the interest for this valve among other researchers. One important conclusion is that the inductance of the pilot solenoid is often limiting the bandwidth of the valve as a whole. 

  • 303.
    Eriksson, Björn
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Mechanical Engineering, Fluid and Mechanical Engineering Systems.
    Larsson, Jonas
    Linköping University, The Institute of Technology. Linköping University, Department of Mechanical Engineering, Fluid and Mechanical Engineering Systems.
    Palmberg, Jan-Ove
    Linköping University, The Institute of Technology. Linköping University, Department of Mechanical Engineering, Fluid and Mechanical Engineering Systems.
    A Novel Valve Concept Including the Valvistor Poppet Valve2008In: Ventil : revija za fluidno tehniko in avtomatizacijo, ISSN 1318-7279, Vol. 14, no 5, p. 433-442Article in journal (Other academic)
    Abstract [en]

    These days, energy efficient mobile fluid power systems are of great interest. A mobile system containing several different cylinder drives supplied with a single load sensing pump (LS-pump) has a number of advantages as well as disadvantages. One of the main advantages is the need of only one system pump. This makes the fluid power system compact and cost-effective. A challenge is to keep the hydraulic losses at low level, especially losses at smaller loads. This paper introduces a fail-safe proportional valve element that is based on the Valvistor poppet valve. Due to the demands of flexibility the poppet valve is bi-directional. The valve has an innovative hydro-mechanical layout that makes it fail-safe, unwanted lowering loads, for example, never occur. The new valve includes simple sensors that are suitable for identification of mode switches, e g between normal, differential and regenerative modes. It is also possible to maneuver the system with maintainted velocity control in the case of sensor failure. In a less complex system the concept has benefits as well. For example in systems where fail-safe-bi-directional on/off valves are needed, then without mode sensing capabilities.

  • 304.
    Eriksson, Björn
    et al.
    Linköping University, Department of Mechanical Engineering, Fluid and Mechanical Engineering Systems. Linköping University, The Institute of Technology.
    Palmberg, Jan-Ove
    Linköping University, Department of Mechanical Engineering, Fluid and Mechanical Engineering Systems. Linköping University, The Institute of Technology.
    Individual Metering Fluid Power Systems: Challenges and Opportunities2011In: Proceedings of the Institution of mechanical engineers. Part I, journal of systems and control engineering, ISSN 0959-6518, E-ISSN 2041-3041, Vol. 225, no 12, p. 196-211Article in journal (Refereed)
    Abstract [en]

    A review of recent and current research on individual metering fluid power systems is presented. An overview of different systems and their pros and cons is given. General challenges related to independent metering fluid power systems are discussed. The major choices in the design of these systems are the hardware layout and the control strategy. The evolution of existing independent metering fluid power systems from the 1970s until the present day is also presented.

  • 305.
    Eriksson, Björn
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Mechanical Engineering, Fluid and Mechanical Engineering Systems.
    Palmberg, Jan-Ove
    Linköping University, The Institute of Technology. Linköping University, Department of Mechanical Engineering, Fluid and Mechanical Engineering Systems.
    Modellering och design av Valvistorn2007In: Hydraulikdagar 07,2007, Linköping: Linköpings universitet , 2007Conference paper (Other academic)
    Abstract [sv]

     Detta paper presenterar en modellering av den kända Valvistorventilen samt en ny utvidgning av denna ventil som ger den proportionalegenskaper i två flödesriktningar på ett fail-safe sätt.

  • 306.
    Eriksson, Björn
    et al.
    Linköping University, Department of Mechanical Engineering, Fluid and Mechanical Engineering Systems. Linköping University, The Institute of Technology.
    Rösth, Marcus
    MCD Parker Hannifin AB.
    Palmberg, Jan-Ove
    Linköping University, Department of Mechanical Engineering, Fluid and Mechanical Engineering Systems. Linköping University, The Institute of Technology.
    A High Energy Efficient Mobile Fluid Power System: Novel System Layout and Measurements2008Conference paper (Other academic)
    Abstract [en]

    This is one of the earliest publications of the proposed energy efficient individual metering system shown in chapter 5, section 5.3.3. This paper introduces the novel system design, which utilizes independent meter-in and meter-out valves. This system design has the potential to increase energy efficiency considerably in a system that consists of a pump  connected to more than one fluid power actuator. The system proposed here is not dependent on pressure transducers for either flow control or mode selection. The main difference between the work presented in this paper and earlier work is the control strategy. The output signal choices in the closed loops are new. Some functionality is kept in hardware to avoid  critical sensor dependency. The presented system uses pressure compensators to achieve desired flows.

  • 307.
    Eriksson, Manne
    Linköping University, Department of Mechanical Engineering.
    Matematisk modellering av industriell luftridå: En jämförelse av effektivitet och elprisets påverkan av driftskostnader2006Independent thesis Advanced level (degree of Magister), 20 points / 30 hpStudent thesis
    Abstract [en]

    The Swedish electricity price has rapidly increased during the last years and is predicted to further increase in the coming years. The main reason is the deregulation of the European electricity market which has begun. As a result Swedish companies have become interested in decreasing their use of electricity to maintain their competitiveness towards foreign companies. A common way to save electricity is to install an air curtain at a door or gate between an adjacent premises or surroundings with different temperature. By aiming plane jets with high velocity at the gate, the different air volumes possibility to mix is reduced. The air curtain therefore protects against draft and maintains the temperature of the premises which improves the thermal comfort. An air curtain working properly can both improve working environment and save energy.

    This report is a final thesis performed for Boxholm Stål in cooperations with the department of energy systems, IKP, Linköping University. The main goal is to examine the flow and efficiency of an air curtain for an industrial gate at Boxholm Stål. By developing and validating a simulation model based on a real air curtain, the efficiency can be estimated. Furthermore, the model will be modified to create alternative configurations which will be compared with the original model. The thesis will also bring knowledge of how a future electricity price will affect the energy costs for operating the air curtain.

    To perform these calculations, CFD, a tool for mathematical modeling of fluids was used. The computer programs Gambit and Fluent were used to create the models, perform and present the numerical calculations.

    The result shows that an air curtain working correctly can both improve the working conditions and reduce the operating costs for heating the premises. Comparisons between the models show large differences in efficiency depending of the positions of the air curtain relative to the gate and the angle at which the air is ejected from the inlet. Solely by modifying the angle for the existing inlet, the operating costs can be reduced by over 60 % compared to a gate without an air curtain.

    The electricity price’s influence on the operating costs is very large since a poorly operating air curtain is pulling large quantities of air, from the premises to the surroundings, which has to be replaced by heated outdoor air. A modified angle on the air curtain can reduce the operating costs even for a higher electricity price in the future.

    For an air curtain placed above the gate, the angle of the inlet is of greater importance than the air velocity. The optimal angle for the inlet is between 20 and 30 degrees independent of the air velocity.

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  • 308.
    Eriksson, Ola
    et al.
    Linköping University, Department of Biomedical Engineering. Linköping University, The Institute of Technology.
    Wren, Joakim
    Linköping University, Department of Mechanical Engineering, Fluid and Mechanical Engineering Systems. Linköping University, The Institute of Technology.
    Loyd, Dan
    Linköping University, Department of Mechanical Engineering, Fluid and Mechanical Engineering Systems. Linköping University, The Institute of Technology.
    Wårdell, Karin
    Linköping University, Department of Biomedical Engineering. Linköping University, The Institute of Technology.
    A comparison between in vitro studies of protein lesions generated by brain electrodes and finite element model simulations1999In: Medical and Biological Engineering and Computing, ISSN 0140-0118, E-ISSN 1741-0444, Vol. 37, no 6, p. 737-741Article in journal (Refereed)
    Abstract [en]

    The aim of this study was to develop a finite element model for simulation of the thermal characteristics of brain electrodes and to compare its performances with an in vitro experimental albumin model. Ten lesions were created in albumin using a monopolar electrode connected to a Leksell Neuro Generator and a computer-assisted video system was used to determine the size of the generated lesions. A finite element model was set up of the in vitro experiments using the same thermal properties. With a very simple heat source applied to the finite element model in the proximity of the upper part of the tip, a good agreement (no deviations in width and distance from tip but a deviation in length of −1.6 mm) with the in vitro experiments (width 4.6±0.1 mm and length 7.4±0.1 mm) was achieved when comparing the outline of the lesion. In addition, a gelatinous albumin-model was set up and compared to computer simulations resulting in deviations in width of −0.4 mm, length of −2.2 mm and distance from the tip of −0.1 mm. Hence, the utilisation of finite element model simulations may be a useful complement to in-vitro experiments.

  • 309.
    Eriksson, Ola
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Biomedical Engineering, Biomedical Instrumentation.
    Wårdell, Karin
    Linköping University, The Institute of Technology. Linköping University, Department of Biomedical Engineering, Biomedical Instrumentation.
    Wren, Joakim
    Linköping University, The Institute of Technology. Linköping University, Department of Mechanical Engineering, Applied Thermodynamics and Fluid Mechanics.
    Loyd, Dan
    Linköping University, The Institute of Technology. Linköping University, Department of Mechanical Engineering, Applied Thermodynamics and Fluid Mechanics.
    A finite element model for brain electrodes and its comparison with in-vitro albumin lesions1999In: Congress of the International Society for Neurosurgical Technology and Instrument Invention ISNTII,1999, 1999Conference paper (Other academic)
  • 310. F, Pfeiffer
    et al.
    Ch., Glocker
    Johansson, Lars
    Linköping University, The Institute of Technology. Linköping University, Department of Mechanical Engineering, Engineering Mechanics.
    An Algorithm for Rigid Body Contact with Coulomb Friction2000In: TUTAM Symposium on Unilateral Multibody Dynamics,1999, 2000Conference paper (Other academic)
  • 311.
    Feng, Xiaolong
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Management and Engineering, Machine Design.
    Sander- Tavalley, S.
    Ölvander, Johan
    Linköping University, The Institute of Technology. Linköping University, Department of Mechanical Engineering, Machine Design.
    Cycle-based Robot Drive Train Optimization Utilizing SVD Analysis2008In: ASME Design Automation Conference,2007, Las Vegas: ASME , 2008, p. 903-910Conference paper (Refereed)
    Abstract [en]

    Designing a drive train for an industrial robot is a demanding task where a set of design variables need to be determined so that optimal performance is obtained for a wide range of different duty cycles. The paper presents a method where singular value decomposition (SVD) is used to reduce the design variable set. The application is a six degree of freedom serial manipulator, with nine drive train parameters for each axis and the objective is to minimize the cycle time on 122 representative design cycles without decreasing the expected lifetime of the robot. The optimization is based on a simulation model of the robot and conducted on a reduced set of the initial duty cycles and with the design variables suggested by the SVD analysis. The obtained design reduces the cycle time with 1.6% on the original design cycles without decreasing the life time of the robot.

  • 312.
    Fernadez, R
    et al.
    Dept of Physical Metallurgy CENIM, Madrid.
    Bruno, G
    Institute Laue-Langevin Genoble.
    Peng, Ru
    Linköping University, The Institute of Technology. Linköping University, Department of Mechanical Engineering, Engineering Materials.
    Gonzalez-Doncel, G
    Dept of Physical Metallurgy CENIM, Madrid.
    Effect of Plastic Deformation on the Microscopic Residual Stresses in 6061Al-15vol%SiCw Composites2003In: THERMEC,2003, 2003Conference paper (Refereed)
  • 313.
    Fernandez, R
    et al.
    Dept of Physical Metallurgy Centro Nacional de Invesigaciones Metalurgicas, Madrid.
    Bruno, G
    Institut Lau-Langevin Grenoble.
    Peng, Ru
    Linköping University, The Institute of Technology. Linköping University, Department of Mechanical Engineering, Engineering Materials.
    Gonzalez-Doncel, G
    Dept of Physical Metallurgy Centro Nacional de Investigaciones Metalurgicas, Madrid.
    Effect of heat treatments on the residual stress state of 60661Al-15%SiCw composite2003In: Meca Sens,2003, 2003Conference paper (Refereed)
  • 314.
    Fernegård, Hans
    Linköping University, Department of Mechanical Engineering.
    Automatisk plastlisthanterare2005Independent thesis Basic level (professional degree), 10 points / 15 hpStudent thesis
    Abstract [en]

    Today a lot of goods is transported on wood pallets because it’s practical and enabels a fast way to load cargo. The drawbacks with pallets are that they weight a lot, are big and are relatively expensive. Therefore IKEA has developed plastic lists that can replace the europallet in some applications. In this examwork an automatic handling equipment for plastic lists are design from a requirement specification to a finished machine. The task of the plastic list handler task is to automatically mount plastic lists under goods. To make the engineering design work easier the plastic list handler were divided in to modules.

    The examwork has been performed at Linköpings Tekniska Högskola, Institutionen för konstruktions- och produktionsteknik, and at TEXO Application in Älmhult. TEXO Application started in 2001 by Bo Lidbom in purpose to find new market areas for TEXO Holding.

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  • 315.
    Fernström, Agneta
    Linköping University, Department of Mechanical Engineering.
    En gustaviansk soffas resa genom två sekel: Efterforskningar, dokumentation och restaurering av en soffa från Löfstad slott2006Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The object of this project is a Gustavian sofa from Löfstad Castle. My aim was to demonstrate the alterations that upholstered furniture can undergo over two hundred years, showing what is original and what has been added at a later date. It is possible to obtain information from all the traces of restoration. In this sofa I found the stamp of the cabinetmaker, which made it possible to date the frame of the sofa. Furthermore, after thorough investigation I was able to determine that the filling of the sofa was much younger than the frame. My purpose was also to restore the sofa to an appearance as close as possible to the state that it had on the death of Emilie Piper, the last owner of Löfstad, in 1926. However, I also had to respect Emilie Piper’s will which stipulated that nothing was to be changed after her death. Finally, I also present my research concerning the history of this Gustavian sofa and its various owners.

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  • 316.
    Filla, Reno
    Linköping University, Department of Mechanical Engineering, Fluid and Mechanical Engineering Systems. Linköping University, The Institute of Technology.
    Alternative system solutions for wheel loaders and other construction equipment2008Conference paper (Other academic)
    Abstract [en]

    Within the Volvo Group there exist long-ranging experiences regarding hybrid propulsions systems for heavy commercial vehicles of the brands Volvo Trucks, Renalt Trucks, Mack Trucks, Nissan Diesel and Volvo Bus. For commercial vehicles like these, hybrid technology is to be regarded seriously and a business case is often given. The search for energy efficient solutions goes on also for construction equipment, and hybrids are everyone's topic. Within Volvo Construction Equipment there is a tradition of researching and developing energy efficient solutions, an example of which was the presentation of a first prototype of a hybrid wheel loader in the beginning of 2008. In this paper the wheel loader will be used as an example for other types of construction machinery. Using a systematic design approach, several more principle design solutions can be found. Reduced fuel consumption by 50% while keeping the performance and productivity at the same level is only possible by considering the complete machine as one system using a holistic approach. 

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  • 317.
    Filla, Reno
    Linköping University, The Institute of Technology. Linköping University, Department of Mechanical Engineering, Fluid and Mechanical Engineering Systems.
    Effektivare hjullastare: Hybrider?2007In: Hydraulikdagar 07,2007, Linköping: Linköpings universitet , 2007Conference paper (Other academic)
    Abstract [sv]

    Med allt högre bränslepriser och den tilltagande samhällsdebatten om växthusgaser och klimatförändringar förvånar det inte att även företag utanför personbilsbranschen undersöker alternativa systemlösningar för att minska avgasutsläppen och oljeberoendet. Detta föredrag presenterar Volvo CEs satsning på elhybrider med fokus på hjullastare.

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  • 318.
    Fjellman, Jonas
    Linköping University, Department of Mechanical Engineering.
    Köksluckor i svenska stadslägenheter 1920-1980: Pådrivande faktorer, material, konstruktion och utseende2006Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis presents the development of doors for kitchen cupboards in Swedish city-flats from a cultural, technique and social science perspective.

    The study consists of two main parts. The first is focused on describing and explaining the overall factors for the development of kitchen cupboard-door manufacture into an industrial and standardized manufacturing process.

    The second part presents a summary of the develpment of kitchen cupboard-doors from the 1920’s to the 1980’s. It deals with materials, construction and appearance. The description refers to the first part and the overall factors which have influenced the development.

    The attempt with this disposition has been to try to present that it should be able to put the development of doors for kitchen cupboards into a larger perspective. To see the door as the end-point marker in a story.

    The result of this work shows that it is possible to place the door in a larger perspective and regard it as a conclusive time-marker. In between the time-limits for this thesis it is possible for the door to function as a start or an end in a story of the construction of welfare Sweden.

  • 319.
    Fjällström, Per-Olof
    et al.
    Linköping University, Department of Computer and Information Science, ACTLAB - Laboratory for Complexity of Algorithms. Linköping University, The Institute of Technology.
    Petersson, Jan
    Linköping University, Department of Science and Technology, Visual Information Technology and Applications (VITA). Linköping University, The Institute of Technology.
    Nilsson, Larsgunnar
    Linköping University, Department of Mechanical Engineering, Solid Mechanics. Linköping University, The Institute of Technology.
    Zhong, Zhi-Hua
    Evaluation of Range Searching Methods for Contact Searching in Mechanical Engineering1998In: International Journal of Computational Geometry & Applications, ISSN 0218-1959, Vol. 8, no 1, p. 67-83Article in journal (Refereed)
    Abstract [en]

    Contact searching is an important and time-consuming part of computer simulation of certain deformation processes. Contact searching can be facilitated by orthogonal range searching. We have experimentally evaluated four methods for orthogonal range searching: the projection method, the cell method, the k-d tree method, and the range tree method.

     

    The results of our experiments indicate that two of these methods, the cell and k-d tree methods, have practical significance. The cell method is in most cases faster than the k-d tree method.

  • 320.
    Follin, Per
    et al.
    Linköping University, Department of Mechanical Engineering.
    Persson, Peter
    Linköping University, Department of Mechanical Engineering.
    Förstudie av utbildningshjälpmedel och beslutsstöd för Rules of Engagement inom svenska Marinen2004Independent thesis Basic level (professional degree)Student thesis
    Abstract [sv]

    Förstudiens syfte var att kartlägga användarbehov kring ROE inom svenska Marinen och ta fram stöd och hjälpmedel för att underlätta ROE-arbetet. I kartläggningen medverkade personal från olika staber, förband och skolor inom Försvarsmakten. Flertalet deltog sedan också i det iterativa utvecklingsarbetet.

    Tre användargrupper urskiljdes; Stabs- och fartygspersonal samt personal under utbildning. Några av de svårigheter som identifierades; Tolkningsskiljaktigheter mellan stabs- och fartygspersonal. ROE-arbetet ger ett administrativt merjobb för stabs- och fartygspersonal. Det finns inte tid eller resurser att öva ROE på ett realistiskt sätt med lämplig upptrappning av hotnivå. Det bedrivs ingen specifik ROE-utbildning vid Försvarsmaktens skolor eller centra.

    Utvecklingsarbetet bedrevs parallellt med kartläggningen och involverade stabs- och fartygspersonal. Efter ett antal utvärderingar med användare kunde tre koncept för stöd och hjälpmedel ges. För att öka förståelsen och visualisera koncepten har tre demonstratorer skapats. Koncepten har fått arbetsnamnen;

    - ADMIN - Administrativt stöd för ROE-hantering.

    - FARTYG - Utbildningshjälpmedel för fartygsledning och eventuellt skolor.

    - STAB - Stöd för framtagning av ROE-profil.

    Författarna rekommenderar FOI att fortsätta utreda ROE-arbetet inom Försvarmakten och även internationellt samt vidareutveckla de tre föreslagna koncepten. För att skapa en gemensam grund för sin personal bör Försvarsmakten hålla seminarium och utbildning inom ROE och tydligare definiera ansvarsförhållanden och begrepp.

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  • 321.
    Forsberg, Jimmy
    Linköping University, Department of Mechanical Engineering, Solid Mechanics. Linköping University, The Institute of Technology.
    Structural optimization in vehicle crashworthiness design2005Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    This thesis concerns the optimization of structures subjected to impact loading. Major applications can be found in the crashworthiness design of vehicles. There is an industrial interest in using optimization methods in the crashworthiness design process. However, strongly nonlinear responses, including high frequency components, make the Finite Element (FE) simulations computationally demanding. This fact restricts the number of possible optimization methods that can be applied.

    In this work two optimization methods have been investigated: Response Surface Methodology (RSM) and Kriging. In both these methods the number of functional evaluations, i.e. here FE simulations, depends at least linearly on the number of design parameters. Thus, the number of design parameters is limited due to the computational effort. One objective of this work has been to reduce the total computational cost of the optimization process, or alternatively the possibility to use more design parameters at the same computational cost. When using RSM and Kriging, the number of functional evaluations in each iteration can be reduced, and/or the convergence of the optimization process can be improved. In many applications, RSM has been used with linear approximating response surfaces for robustness and efficiency reasons. Linear RSM may suffer from iterative oscillations, since the optimal design is often found on the boundary of the feasible design region. This oscillatory behaviour can be reduced if Kriging is used for the approximating response surfaces. However, it has been found that Kriging may have problems in fulfilling the constraints. In the initial design process of a structure very many alternative designs exist. At these early stages topology optimization is a mean of finding a structure that is optimal for the objective at hand. In this work a topology optimization approach is proposed for the design of crashworthiness structures. The resulting structure must still be subjected to an interpretation by engineers and also be improved by further optimization.

    List of papers
    1. Using the response surface methodology and the D-optimality criterion in crashworthiness related problems
    Open this publication in new window or tab >>Using the response surface methodology and the D-optimality criterion in crashworthiness related problems
    2002 (English)In: Structural and multidisciplinary optimization (Print), ISSN 1615-147X, E-ISSN 1615-1488, Vol. 24, no 3, p. 185-194Article in journal (Refereed) Published
    Abstract [en]

    The aim of this paper is to determine the efficient number of experimental points when using the response surface methodology in crashworthiness problems.

    The D-optimality criterion is used as experimental design method. Two application models have been studied, one square tube and one front rail from Saab Automobile AB. Both models were fully parameterized in the preprocessor LS-INGRID but only two design variables were used. The optimization package LS-OPT was used to determine the design of experiments using the D-optimality criterion. Both models were subjected to an impact into a rigid wall and the simulations were carried out using LS-DYNA. A general recommendation is to to use 1.5 times the minimum number of experimental points. A more specialized recommendation is for linear surfaces 1.5, elliptic surfaces 2.2 and for quadratic surfaces 1.6 times the minimum number of experimental points.

    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-35584 (URN)10.1007/s00158-002-0228-9 (DOI)27810 (Local ID)27810 (Archive number)27810 (OAI)
    Available from: 2009-10-10 Created: 2009-10-10 Last updated: 2017-12-13
    2. On polynomial response surfaces and Kriging for use in structural optimization of crashworthiness
    Open this publication in new window or tab >>On polynomial response surfaces and Kriging for use in structural optimization of crashworthiness
    2005 (English)In: Structural and multidisciplinary optimization (Print), ISSN 1615-147X, E-ISSN 1615-1488, Vol. 29, no 3, p. 232-243Article in journal (Refereed) Published
    Abstract [en]

    The accuracy of different approximating response surfaces is investigated. In the classical response surface methodology (CRSM) the true response function is usually replaced with a low-order polynomial. In Kriging the true response function is replaced with a low-order polynomial and an error correcting function. In this paper the error part of the approximating response surface is obtained from “simple point Kriging” theory. The combined polynomial and error correcting function will be addressed as a Kriging surface approximation.

    To be able to use Kriging the spatial correlation or covariance must be known. In this paper the error is assumed to have a normal distribution and the covariance to depend only on one parameter. The maximum-likelihood method is used to find the latter parameter. A weighted least-square procedure is used to determine the trend before simple point Kriging is used for the error function. In CRSM the surface approximation is determined through an ordinary least-square fit. In both cases the D-optimality criterion has been used to distribute the design points.

    From this investigation we have found that a low-ordered polynomial assumption should be made with the Kriging approach. We have also concluded that Kriging better than CRSM resolves abrupt changes in the response, e.g. due to buckling, contact or plastic deformation.

    Keywords
    Crashworthiness, FEM, Kriging RSM
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-45499 (URN)10.1007/s00158-004-0487-8 (DOI)
    Available from: 2009-10-11 Created: 2009-10-11 Last updated: 2017-12-13
    3. Evaluation of response surface methodologies used in crashworthiness optimization
    Open this publication in new window or tab >>Evaluation of response surface methodologies used in crashworthiness optimization
    2006 (English)In: International Journal of Impact Engineering, ISSN 0734-743X, E-ISSN 1879-3509, Vol. 32, no 5, p. 759-777Article in journal (Refereed) Published
    Abstract [en]

    Optimization of car structures is of great interest to the automotive industry. This work is concerned with structural optimization of a car body with the intent to increase the crashworthiness properties of the vehicle or decrease weight with the crashworthiness properties unaffected. In this work two different methodologies of constructing an intermediate approximation to the optimization problem are investigated, i.e. classical response surface methodology and Kriging. The major difference between the two methodologies is how the residuals between the true function value and the polynomial surface approximation value at a design point are treated.

    Several different optimization problems have been investigated, both analytical problems as well as finite element impact problems.

    The major conclusion is that even if the same kind of updating scheme is used both for Kriging and linear classic response surface methodology, Kriging improves the sequential behaviour of the optimization algorithm in the beginning of the optimization process. Problems may occur if a constraint is violated after several iterations and then classic response surface methodology seems to more easily be able to find a design point which satisfies the constraint.

    Keywords
    RSM, kriging, I-S-DYNA, crashworthiness optimization
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-46051 (URN)10.1016/j.ijimpeng.2005.01.007 (DOI)
    Available from: 2009-10-11 Created: 2009-10-11 Last updated: 2017-12-13
    4. The optimisation process of an energy absorbing frontal underrun protection device
    Open this publication in new window or tab >>The optimisation process of an energy absorbing frontal underrun protection device
    2008 (English)In: International Journal of Vehicle Design, ISSN 0143-3369, E-ISSN 1741-5314, Vol. 46, no 3, p. 271-293Article in journal (Refereed) Published
    Abstract [en]

    This paper describes the methodology used during the development of an energy absorbing Frontal Underrun Protection device (eaFUP). The aim of this study is to show how different optimisation methods can be used at different stages during the design process. It also shows one approach to derive an optimal design taking several different design alternatives into account, each of which consists of several different materials. The outcome of the optimisation process is three different designs of the eaFUP.

    Keywords
    Design process, FEM, Finite element method, Frontal underrun protection, FUP, Optimisation, Response surface methodology, RSM
    National Category
    Natural Sciences
    Identifiers
    urn:nbn:se:liu:diva-46033 (URN)10.1504/IJVD.2008.019087 (DOI)
    Available from: 2009-10-11 Created: 2009-10-11 Last updated: 2017-12-13
    5. Topology optimization in crashworthiness design
    Open this publication in new window or tab >>Topology optimization in crashworthiness design
    2007 (English)In: Structural and multidisciplinary optimization (Print), ISSN 1615-147X, E-ISSN 1615-1488, Vol. 33, no 1, p. 1-12Article in journal (Refereed) Published
    Abstract [en]

    Topology optimization has developed rapidly, primarily with application on linear elastic structures subjected to static loadcases. In its basic form, an approximated optimization problem is formulated using analytical or semi-analytical methods to perform the sensitivity analysis. When an explicit finite element method is used to solve contact–impact problems, the sensitivities cannot easily be found. Hence, the engineer is forced to use numerical derivatives or other approaches. Since each finite element simulation of an impact problem may take days of computing time, the sensitivity-based methods are not a useful approach. Therefore, two alternative formulations for topology optimization are investigated in this work. The fundamental approach is to remove elements or, alternatively, change the element thicknesses based on the internal energy density distribution in the model. There is no automatic shift between the two methods within the existing algorithm. Within this formulation, it is possible to treat nonlinear effects, e.g., contact–impact and plasticity. Since no sensitivities are used, the updated design might be a step in the wrong direction for some finite elements. The load paths within the model will change if elements are removed or the element thicknesses are altered. Therefore, care should be taken with this procedure so that small steps are used, i.e., the change of the model should not be too large between two successive iterations and, therefore, the design parameters should not be altered too much. It is shown in this paper that the proposed method for topology optimization of a nonlinear problem gives similar result as a standard topology optimization procedures for the linear elastic case. Furthermore, the proposed procedures allow for topology optimization of nonlinear problems. The major restriction of the method is that responses in the optimization formulation must be coupled to the thickness updating procedure, e.g., constraint on a nodal displacement, acceleration level that is allowed.

    Keywords
    Contact-impacts, Explicit finite element analysis, Nonlinear problems, Topology optimization
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-50018 (URN)10.1007/s00158-006-0040-z (DOI)
    Available from: 2009-10-11 Created: 2009-10-11 Last updated: 2017-12-12
  • 322.
    Forslund, Pontus
    Linköping University, Department of Mechanical Engineering.
    A Neural Network Based Brain-Computer Interface for Classification of Movement Related EEG2003Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    A brain-computer interface, BCI, is a technical system that allows a person to control the external world without relying on muscle activity. This thesis presents an EEG based BCI designed for automatic classification of two dimensional hand movements. The long-term goal of the project is to build an intuitive communication system for operation by people with severe motor impairments. If successful, such system could for example be used by a paralyzed patient to control a word processor or a wheelchair.

    The developed BCI was tested in an offine pilot study. In response to an external cue, a test subject moved a joystick in one of four directions. During the movement, EEG was recorded from seven electrodes mounted on the subject's scalp. An autoregressive model was fitted to the data, and the extracted coefficients were used as input features to a neural network based classifier. The classifier was trained to recognize the direction of the movements. During the first half of the experiment, real physical movements were performed. In the second half, subjects were instructed just to imagine the hand moving the joystick, but to avoid any muscle activity.

    The results of the experiment indicate that the EEG signals do in fact contain extractable and classifiable information about the performed movements, during both physical and imagined movements.

    Download full text (pdf)
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  • 323.
    Franzén, Bertil
    Linköping University, Department of Mechanical Engineering. Linköping University, The Institute of Technology.
    A support method for the design of disassembly friendly products: with regards to ecology and economy2001Licentiate thesis, monograph (Other academic)
    Abstract [en]

    Environmentally adapted products will be a necessity for trade and industry in a near future. In densely populated countries or areas there is no space left to put waste on landfill. Awareness that our natural resources are limited has also been accepted. If we shall have our high standard of living and let it grow, and also increase the standard of living for the rest of the world we must find tangible solutions how to use our natural resources in a sustainable way.

    This thesis presents an approach how to, with a structured methodology, collect information and knowledge from old products for use in the product developing process. Focus in this collecting will be on environmental issues. The approach is the result from case studies done in the EUREKA-project CLEANTECH. The approach has been continuously improved during the execution of these case studies. The approached constitutes a structure, how to work, and a checklist, what to have in mind. The structure and the checklist have been tested in the product development department of Swedish companies.

    In the case studies, different products have been disassembled and the results from that are knowledge how to work in a structured way and development of a knowledge base. The knowledge base resulted into the checklist. During the disassembly discussions have been held with representatives from disassembly industries and from product development departments.

    To understand what happens at a specific stage in the product development process, a literature study has been done on this topic. Some of the most well known descriptions of the product development process have been penetrated. The result from this survey is a modified product development process that has been used as a base in this thesis.

    In this modified process new activities have been included, activities that facilitate the integration of environmental issues in the product development process. Every phase, step and activity in the product development process has been penetrated to point out the environmental activities and aspects to be focused.

    The purpose of this thesis is to give an example of how to integrate environmental aspects with the product development process. This integration must be done in such a way that environmental aspects are ordinary topics in the development of new products.

  • 324.
    Franzén, Thomas
    Linköping University, Department of Mechanical Engineering, Energy Systems. Linköping University, The Institute of Technology.
    EnSAM - EnergiSystemAnalysMetod för industriella energisystem2005Licentiate thesis, monograph (Other academic)
    Abstract [en]

    Traditionally, Swedish industries have been experiencing lower power prices compared with industries in the European continent. The specific power consumption is 2- 3 times higher than other competing industries abroad.

    Since July 2004, the power market is deregulated where industries have the possibility to choose supplier. This could imply a harmonized price level across the continent. This would be disadvantageous for Swedish companies if nothing will be done to reduce power consumption.

    Marginal power production is based on coal-fired condensing power plant in the European power system. Independent of location, reducing the use of electricity would affect the use of expensive and environmentally not favorable plants.

    In this thesis a method that can be used by nearly all industries is presented. The method has been applied on different case studies within different projects like project in Volvo Cars plants in Guthenburg and Gent, Electrolux cooker manufacturing in three European cities, Fredericia in Denmark, Spennymoor in England, Motala in Sweden and in the Oskarshamn area and a similar project ELOST in Östergotland and within program "Uthållig kommun" in Sweden.

    The studies show that the all industries that are considered can reduce their electricity energy use by about 50 %. This would imply significant reduction of carbon dioxide emission in the continent.

    Using top-down approach system failures can be identified and corresponding measures can be taken to improve the system. The use of energy can be reduced through energy avoiding cooling and heating at the same time, controlled operation of compressors and the use of power driven tools instead of compressed air driven tools, the use of efficient lamps and controlled ventilation or totally avoiding ventilation in some manufacturing halls, application of district heating driven absorption chillers and no production use can also contribute to reduced electric energy use.

    Experiences from performed case studies indicate that system failures regarding the electricity use have been detected in nearly all investigated industries.

    Three "laws" are distinguished:

    • 1kWh electricity from a coal fires condensing power plant will give rise to aout 1kg CO2 i.i. : 1 kwh el ≈ 1 kg CO2
    • Low electricity price implicate high electricity use and vice versa i.e: (Electricity price) times (specific use) ≈ constant
    • The efficiency of a coal fired condensing power plant is about 30% which implicate: Electricity price > three times the fuel price
  • 325.
    Fredricson, Harald
    Linköping University, Department of Mechanical Engineering, Solid Mechanics. Linköping University, The Institute of Technology.
    Optimization methods for vehicle body structures2002Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    This thesis is concerned with the use of optimization methods in the vehicle industry. Numerical optimization has been used with limited extend in the vehicle industry. However, great potential of using optimization methods has been identified during the development process of vehicle body structures. One driving force in this direction is the increased focus on building lighter and cheaper vehicles with better crashworthiness. There is also an interest, from an academic point of view in the area of optimization research, to establish the use of optimization methods in the industry.

    This thesis presents a method that introduces optimization as a tool to be used during the design procedure of vehicle body structures. The three included papers introduces a way of including optimization methods during the development of vehicle body structures.

  • 326.
    Fredricson, Harald
    Linköping University, Department of Mechanical Engineering. Linköping University, The Institute of Technology.
    Topology optimization of vehicle body structures: method, theory and applications2004Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    This dissertation is concerned with topology optimization of vehicle body structures.

    The first part of this thesis gives a summary of the research project. A design process for complex mechanical structures is presented. This design process includes an optimization step where simplified models are optimized. These simplified models are frame structures consisting of beams and joints. Joints are modelled as a collection of sub-elements to support for a topological change during optimization. Parameterization of beams and joint is also presented and design variables are introduced.

    An application of this frame topology optimization method, concerning a vehicle body structure, is presented.

    Two extensions to the theory are also presented. First, the possibility to penalize joints to support for easily realizable results is presented. This is followed by a two-material interpolation that introduces the possibility of using a mixed material structure.

    This introductory part is followed by five appended papers produced within the framework of this research.

    List of papers
    1. A design process for complex mechanical structures using property based models, with application to car bodies
    Open this publication in new window or tab >>A design process for complex mechanical structures using property based models, with application to car bodies
    2002 (English)In: Proceedings of the 7th International Design Conference: DESIGN 2002 / [ed] D. Marjanovic, 2002, p. 611-620Conference paper, Published paper (Refereed)
    Abstract [en]

    The design of complex mechanical structures is multi-objective and includes the treatements of a wide range of requirements such as quantitative, qualitative, subjective and objective. An example of this type of structure is a car body, where design has a long tradition from wich valuable experience can be drawn however fixation to old practises has to be avoided. The design process described in the paper aims to reduce lead time while not excluding innovative solutions. By representing all concepts on a common base as a property based model and use optimisation, an objective analysis can be done early thereby only viable concepts will emerge to further selection. The data gained at early phases is used as input to detail design reducing iterations.

    Keywords
    Design method, concept selection, optimisation, structural design, mechanical structures, multi-objective
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-87817 (URN)
    Conference
    DESIGN2002 Conference, 14-17 May, Cavtat, Croatia 2002
    Available from: 2013-01-23 Created: 2013-01-23 Last updated: 2013-01-23
    2. Structural topology optimisation: an application review
    Open this publication in new window or tab >>Structural topology optimisation: an application review
    2005 (English)In: International Journal of Vehicle Design, ISSN 0143-3369, E-ISSN 1741-5314, Vol. 37, no 1, p. 67-80Article in journal (Refereed) Published
    Abstract [en]

    This paper presents a survey of the literature on the use of structural topology optimisation in the vehicle industry. The focus is on some specific applications rather than on any specific optimisation discipline. The survey starts with a general historic resume and continues with a more detailed description of the status today. New applications and areas for optimisation are presented, with short summaries of the referred papers. The major focus is on applications for vehicle body structures. Trends and potential areas of research are also explored.

    Place, publisher, year, edition, pages
    InderScience Publishers, 2005
    Keywords
    structural topology optimisation; vehicle applications; vehicle industry
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-87819 (URN)10.1504/IJVD.2005.006089 (DOI)000227723100004 ()
    Available from: 2013-01-23 Created: 2013-01-23 Last updated: 2017-12-06
    3. Topology optimization of frame structures with flexible joints
    Open this publication in new window or tab >>Topology optimization of frame structures with flexible joints
    2003 (English)In: Structural and multidisciplinary optimization (Print), ISSN 1615-147X, E-ISSN 1615-1488, Vol. 25, no 3, p. 199-214Article in journal (Refereed) Published
    Abstract [en]

    A method for structural topology optimization of frame structures with flexible joints is presented. A typical frame structure is a set of beams and joints assembled to carry an applied load. The problem considered in this paper is to find the stiffest frame for a given mass. By introducing design variables for beams and joints, a mass distribution for optimal structural stiffness can be found. Each beam can have several design variables connected to its cross section. One of these is an area-type design variable which is used to represent the global size of the beam. The other design variables are of length ratio type, controlling the cross section of the beam. Joints are flexible elements connecting the beams in the structure. Each joint has stiffness properties and a mass. A framework for modelling these stiffnesses is presented and design variables for joints are introduced. We prove a theorem which can be interpreted as the fact that the removal of structural elements, e.g. joints or beams, can be modelled by a small strictly positive material amount assigned to the element. This is needed for the computations of sensitivities used in the applied gradient based iterative method. Both two and three dimensional problems, as well as multiple load cases and multiple mass constraints, are treated.

    Keywords
    Flexible joints, Frame structures, Joint modelling, Topology optimization
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-46540 (URN)10.1007/s00158-003-0281-z (DOI)
    Available from: 2009-10-11 Created: 2009-10-11 Last updated: 2017-12-13
    4. Topology optimization of frame structures: a vehicle body application
    Open this publication in new window or tab >>Topology optimization of frame structures: a vehicle body application
    (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    An application of frame topology optimization on a vehicle body structure is presented. A traditional way of describing the elements of a vehicle body structure is by beams and joints. Based on this, the models used in this study are frame structures with flexible joints. The problem considered is to find that stiffest frame design which fulfills a weight requirement. To support for a topological change of joints, each joint is modelled as a set of subelements. A set of design variables are applied to each beam and joint subelement. Two kinds of design variables are used. One of these variables is an area-type design variable used for controlling the global element size and supporting a topology change. The other variables are length ratio variables controlling thecross-section of bemas and internal stiffness properties of joints. The vehicle body application presented in this paper shows the usefulness of topology optimization in the early design phase.

    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-87820 (URN)
    Available from: 2013-01-23 Created: 2013-01-23 Last updated: 2013-01-23
    5. Topology optimization of frame structures: joint penalty and material selection
    Open this publication in new window or tab >>Topology optimization of frame structures: joint penalty and material selection
    2005 (English)In: Structural and multidisciplinary optimization (Print), ISSN 1615-147X, E-ISSN 1615-1488, Vol. 30, no 3, p. 193-200Article in journal (Refereed) Published
    Abstract [en]

    This paper deals with joint penalization and material selection in frame topology optimization. The models used in this study are frame structures with flexible joints. The problem considered is to find the frame design which fulfills a stiffness requirement at the lowest structural weight. To support topological change of joints, each joint is modelled as a set of subelements. A set of design variables are applied to each beam and joint subelement. Two kinds of design variables are used. One of these variables is an area-type design variable used to control the global element size and support a topology change. The other variables are length ratio variables controlling the cross section of beams and internal stiffness properties of the joints. This paper presents two extensions to classical frame topology optimization. Firstly, penalization of structural joints is presented. This introduces the possibility of finding a topology with less complexity in terms of the number of beam connections. Secondly, a material interpolation scheme is introduced to support mixed material design.

    Place, publisher, year, edition, pages
    Springer, 2005
    Keywords
    topology optimization; frame structure; joint penalty; material selection
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-87821 (URN)10.1007/s00158-005-0515-3 (DOI)000234195100003 ()
    Available from: 2013-01-23 Created: 2013-01-23 Last updated: 2017-12-06
  • 327.
    Fredricson, Harald
    et al.
    Volvo Car Corp., Göteborg, Sweden.
    Johansen, Torbjörn
    Volvo Technology Corp., Göteborg, Sweden.
    Klarbring, Anders
    Linköping University, Department of Mechanical Engineering. Linköping University, The Institute of Technology.
    Petersson, Joakim
    Linköping University, Department of Mechanical Engineering. Linköping University, The Institute of Technology.
    Topology optimization of frame structures with flexible joints2003In: Structural and multidisciplinary optimization (Print), ISSN 1615-147X, E-ISSN 1615-1488, Vol. 25, no 3, p. 199-214Article in journal (Refereed)
    Abstract [en]

    A method for structural topology optimization of frame structures with flexible joints is presented. A typical frame structure is a set of beams and joints assembled to carry an applied load. The problem considered in this paper is to find the stiffest frame for a given mass. By introducing design variables for beams and joints, a mass distribution for optimal structural stiffness can be found. Each beam can have several design variables connected to its cross section. One of these is an area-type design variable which is used to represent the global size of the beam. The other design variables are of length ratio type, controlling the cross section of the beam. Joints are flexible elements connecting the beams in the structure. Each joint has stiffness properties and a mass. A framework for modelling these stiffnesses is presented and design variables for joints are introduced. We prove a theorem which can be interpreted as the fact that the removal of structural elements, e.g. joints or beams, can be modelled by a small strictly positive material amount assigned to the element. This is needed for the computations of sensitivities used in the applied gradient based iterative method. Both two and three dimensional problems, as well as multiple load cases and multiple mass constraints, are treated.

  • 328.
    Fundin, Anders
    et al.
    Chalmers tekniska högskola.
    Elg, Mattias
    Linköping University, The Institute of Technology. Linköping University, Department of Mechanical Engineering, Quality Technology and Management.
    Learning from the dissatisfied customer2004In: 7th International QMOD Conference,2004, 2004, p. 181-Conference paper (Refereed)
  • 329.
    Furuhjelm, Jörgen
    Linköping University, Department of Mechanical Engineering. Linköping University, The Institute of Technology.
    Incorporating the end-of-life aspect into product development: analysis and a systematic approach2000Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    It is evident that we face a major challenge to overcome the environmental problems associated with our consumption and production systems. The rate at which products flow through our society is steadily increasing and this leads to serious consequences in the form of accelerating depletion of the earth's resources and generation of enormous amounts of waste. This fact is being paid increasing attention and recent developments of legislation together with a growing market awareness have brought incentives to take the end-of-life aspect into account right from the product development stage. There is thus an industrial need to enhance knowledge on how cost-efficient and environmentally sound treatment of discarded product could be facilitated through design measures.

    This thesis provides an analysis and a systematic approach concerning how the end-of-life aspect could be incorporated during product development. The systematic approach has been created by the author and is mainly based on input from case studies at ABB Motors, Nokia and Ericsson. The approach functions in the thesis as a guiding structure for a comprehensive analysis of how an effective and efficient incorporation could be achieved, leading to products that facilitate cost-efficient recycling.

     In its normative character the approach aims at applicability in companies that want to improve their products' design from an environmental as well as a market perspective. In applying the approach as a normative tool the company is advised to follow a working structure made up of four steps; 1.) Analysing relevant areas, 2.) Deriving product demands for each area, 3.) Establishing a final list of product demands and 4.) Providing support for product development.

    The areas seen as relevant to pay attention to in Step 1 are the market demand related to the end-of-life phase, the take-back legislation currently being implemented and the products' end-of-life system. Applying the approach, the company should detern1ine how the product design could be improved leading to increased market potential, compliance with the legislative demands and cost-efficient end-of-life treatment. Effective design targets should then be established through a synthesis of the demands derived from each area. The fourth step of the approach deals with the actual integration of the end-of-life aspect in relevant product development activities. The thesis then analyses how, on the basis of the established product demands, the end-of-life aspects could be efficiently incorporated. For example, it is discussed how end-of-life-related demands could be included in the design specifications and the end-of-life aspect incorporated into the project management systems. 

  • 330.
    Garcia-Padron, Ricardo
    Linköping University, Department of Mechanical Engineering, Fluid and Mechanical Engineering Systems. Linköping University, The Institute of Technology. Univ.,.
    Heat and water transfer for lacquer drying and thermal signatures: modelling, simulation and experiment2001Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The coupled phenomenon of heat and water transfer is essential in many scientific and industrial problems. This thesis focuses this phenomenon on two areas; lacquer drying and thermal signatures. Simulations of physical phenomena may in some cases replace extensive experimental investigations, which may be complicated and expensive. In other cases simulations may provide means to reduce the number of experiments necessary to perform. In the thesis models, as simple as possible, are used to simulate heat and water transfer. Experiments were made and are compared with the simulations in order to verify the validity of the simplified models.

    In the first part of the thesis the drying of a waterborne lacquer coating used in wood manufacturing industry is investigated. Problems concerning upward water transfer resulting in a specified drying period, and downward water transfer resulting in fibre swelling are addressed. Experiments were made in a full-scale drying plant.

    In the second part of this thesis heat and water transfer in solar radiated sand is investigated. The main purpose of these investigations is to improve the predictions of thermal signatures related to detection of buried objects, e.g. buried land mines. Among several factors, influencing the thermal signatures received by optical systems, water movement in the soil and water evaporation from the surface have been found to be of particular interest. Experiments were made in an indoor test landscape.

    In two related papers two other methods for investigating problems connected to lacquer drying are presented. In the first paper two-way factorial design is used to optimise the drying process of waterborne lacquer coating in a full-scale drying oven. In the second paper the inverse heat conduction problem is used to predict the surface temperature of a particleboard based on measurements inside the board.

  • 331.
    Gauthereau, Vincent
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Mechanical Engineering.
    Hollnagel, Erik
    Linköping University, The Institute of Technology. Linköping University, Department of Computer and Information Science, CSELAB - Cognitive Systems Engineering Laboratory.
    Building expectations and the management of surprises: Studies of safety-train outages at a Swedish nuclear power plant.2003In: European Conference on Cognitive Science Approache to Process Control,2003, 2003Conference paper (Refereed)
  • 332.
    Gauthereau, Vincent
    et al.
    Linköping University, Department of Mechanical Engineering, Quality Technology and Management. Linköping University, The Institute of Technology.
    Hollnagel, Erik
    Linköping University, Department of Computer and Information Science, CSELAB - Cognitive Systems Engineering Laboratory. Linköping University, The Institute of Technology.
    Organisational Improvisation: A Field Study At a Swedish NPP during a Productive-Outage.2002In: European Annual Conference on Human Decision Making and Control, 2002Conference paper (Refereed)
  • 333.
    Gavel, Hampus
    Linköping University, Department of Mechanical Engineering. Linköping University, The Institute of Technology.
    On Aircraft Fuel System Conceptual Design - Conceptual Evaluation and System modeling2004Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    THE LARGEST AND most important fluid system in an aircraft is the fuel system. Obviously, future aircraft projects involve the design of fuel system to some degree. In this project design methodologies for aircraft fuel systems are studied, with the aim to shortening the system development time.

    This is done by means of illustrative examples of how optimization and the use of matrix methods have been developed and implemented at Saab Aerospace in the conceptual design of ale fuel systems. The methods introduces automation early in the development process and increase understanding of how top requirements on the ale level impact low-level engineering parameters such as pipe diameter, pump size, etc.

    The thesis also discusses a systematic approach when building a large simulation model of a fluid system where the objective is to minirnize the development time by applying a strategy that enables parallel development and collaborative engineering, and also by building the mode! to the correct level of detail. By correct level of detail is meant the level that yields a simulation outcome that meets the stakeholders' expectations. The experienced gained at Saab in building a simulation model, mainly from the Gripen fuel system, but also the accumulated experience from other system models, is condensed and fitted into an overall process.

    List of papers
    1. Fuel Transfer System in the Conceptual Design Phase
    Open this publication in new window or tab >>Fuel Transfer System in the Conceptual Design Phase
    2002 (English)In: SAE World Aviation congress and Display, Phoenix, USA paper 2002-01-2931, 2002, no 2002-01-2931Conference paper, Published paper (Refereed)
    Abstract [en]

    As the time between different development projects of new aircraft (a/c) extends, experienced personnel in the field of basic a/c system design are difficult to employ when being on the onset of a new design. Further on basic a/c system design is a field neglected in literature and in the educational system.

    A text is under development that summarizes the Saab experience of the complete fuel system design with respect to the fighter a/c Viggen and Gripen, the commuter a/c 340 and 2000, the trainer a/c SK60 and also the conceptual a/c B3LA.

    This paper is an extract of this text and describe early considerations that have to be made when designing a fuel transfer system. Emphasis is put on the top requirements on a/c level.

    Series
    SAE technical paper series, ISSN 0148-7191
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-12987 (URN)10.4271/2002-01-2931 (DOI)
    Conference
    SAE World Aviation congress and Display, November 5-7, Phoenix, USA
    Available from: 2008-04-01 Created: 2008-04-01 Last updated: 2014-01-21Bibliographically approved
    2. Using Optimization as a Tool in Fuel System Conceptual Design
    Open this publication in new window or tab >>Using Optimization as a Tool in Fuel System Conceptual Design
    2003 (English)In: SAE World Aviation Congress and Display, Montreal, Canada, SAE Technical Paper 2003-01-3054, 2003, no 2003-01-3052Conference paper, Published paper (Refereed)
    Abstract [en]

    Choosing between concepts is often the most critical part of the design process. Different concepts have different advantages and disadvantages. The concept that is the best choice is most often dependent on the top level requirements. Sometimes there may also be a trade off between concept choice and the top requirements. In aircraft (a/c) fuel system design it has often proved difficult to find the switching point where the superior concept is changed. This sometimes makes the designer conservative and leads to the selection of a concept with too high a penalty. There is also a risk for the opposite and perhaps worse scenario: That the designer strives to reduce weight and cost and therefore, accidentally, chooses an under achieving concept and thus induces large downstream cost if late redesign or retro modifications are necessary.

    This paper shows how optimization has been successfully used at Saab Aerospace as a tool that supports concept selection. The example shown is the choice of fuel transfer method for a ventral drop tank. The example also illustrates the impact of top-level requirements on low-level practicalities such as fuel system design.

    Series
    SAE Technical Paper
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-12988 (URN)10.4271/2003-01-3054 (DOI)
    Conference
    SAE World Aviation Congress and Display, WAC 03, September 8-12, Montreal, Canada
    Available from: 2008-04-01 Created: 2008-04-01 Last updated: 2014-01-21Bibliographically approved
    3. Quantification of the Elements in the Relationship matrix: A conceptual study of Aircraft Fuel System
    Open this publication in new window or tab >>Quantification of the Elements in the Relationship matrix: A conceptual study of Aircraft Fuel System
    2004 (English)In: 42nd AIAA Aerospace Sciences Meeting and Exhibit, Reno, USA, paper AIAA-2004-0538, 2004, no AIAA-2004-0538, p. 5244-5252Conference paper, Published paper (Refereed)
    Abstract [en]

    This paper describes how the framework of thc house of quality and design structure matrices are used to visualizee dependencies between top level requirements and engineering design properties. It is also discussed how quantification of the matrix elements may increase the understanding of how the top-level requirements impacts the low-level design parameters. lndeed, history has shown that overlooking combinatory effects between subsystems and night conditions may become expensive. Not only in terms of not goning getting the sizing right but more so if an entirely wrong concept is chosen.

    This paper shows a matrix technique that has successfully been used at Saab and how this technique may facilitate the cconcept evaluation process of early fuel system design.

    The matrix method aids the designer to take alk the relevant aspects into account when evaluating a design. Use of the method will also increase the understanding of what top-level requirement or combination thereof, which drives the choice of one particular concept rather than the other. The understanding of how the top-level requiremEnts impacts low level design parameters such as pump size or pipe diameter will also increse.

    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-12984 (URN)10.2514/6.2004-538 (DOI)
    Conference
    42nd AIAA Aerospace Sciences Meeting and Exhibit, 5-8 Januari, Reno, USA
    Available from: 2008-04-01 Created: 2008-04-01 Last updated: 2014-01-21Bibliographically approved
    4. Strategy for Modeling of large A/C fluid systems
    Open this publication in new window or tab >>Strategy for Modeling of large A/C fluid systems
    Show others...
    2004 (English)In: World Aviation Congress and Display, WAC-04, SAE Technical Paper 2004-01-3093, 2004, p. 1495-1506Conference paper, Published paper (Refereed)
    Abstract [en]

    There is an ongoing trend in the European Military a/c industry towards cooperation between nations when purchasing and between manufacturers when developing and producing a/c. Different manufacturers at different locations develop different parts or sub-systems. When using this approach a vital part of a fast and precise system evaluation is the use of simulation models. In order to stay competitive it is not only sufficient to be able to build large simulation models but also to do it fast.

    This paper describes the conclusions regarding a modelling strategy of large fluid systems drawn from the building of a simulation model of the JAS 39 Gripen fuel system. An overall process is suggested into which the activities of building a model are fitted. This is however not the main objective; it is more important to identify the different issues and activities at the engineering level. If these are properly dealt with, the model development time will be reduced, if not, the wrong model may be designed. "Wrong" here means a model that does not do the job, or solves a problem other than the one intended by the stakeholder.

    Series
    SAE technical paper series, ISSN 0148-7191 ; 3093
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-12981 (URN)10.4271/2004-01-3093 (DOI)
    Conference
    World Aviation Congress and Display, WAC-04, Reno, USA
    Available from: 2008-04-01 Created: 2008-04-01 Last updated: 2014-01-21Bibliographically approved
  • 334.
    Gavel, Hampus
    Linköping University, Department of Mechanical Engineering. Linköping University, The Institute of Technology.
    On aircraft fuel system design: concept evaluation and system modeling2004Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    THE LARGEST AND most important fluid system in an aircraft is the fuel system. Obviously, future aircraft projects involve the design of fuel system to some degree. In this project design methodologies for aircraft fuel systems are studied, with the aim to shortening the system development time.

    This is done by means of illustrative examples of how optimization and the use of matrix methods have been developed and implemented at Saab Aerospace in the conceptual design of ale fuel systems. The methods introduces automation early in the development process and increase understanding of how top requirements on the ale level impact low-level engineering parameters such as pipe diameter, pump size, etc.

    The thesis also discusses a systematic approach when building a large simulation model of a fluid system where the objective is to minimize the development time by applying a strategy that enables parallel development and collaborative engineering, and also by building the model to the correct level of detail. By correct level of detail is meant the level that yields a simulation outcome that meets the stakeholders' expectations. The experienced gained at Saab in building a simulation model, mainly from the Gripen fuel system, but also the accumulated experience from other system models, is condensed and fitted into an overall process.

  • 335.
    Gavel, Hampus
    et al.
    Linköping University, Department of Management and Engineering, Machine Design. Linköping University, The Institute of Technology.
    Andersson, Johan
    Linköping University, Department of Mechanical Engineering. Linköping University, The Institute of Technology.
    Using Optimization as a Tool in Fuel System Conceptual Design2003In: SAE World Aviation Congress and Display, Montreal, Canada, SAE Technical Paper 2003-01-3054, 2003, no 2003-01-3052Conference paper (Refereed)
    Abstract [en]

    Choosing between concepts is often the most critical part of the design process. Different concepts have different advantages and disadvantages. The concept that is the best choice is most often dependent on the top level requirements. Sometimes there may also be a trade off between concept choice and the top requirements. In aircraft (a/c) fuel system design it has often proved difficult to find the switching point where the superior concept is changed. This sometimes makes the designer conservative and leads to the selection of a concept with too high a penalty. There is also a risk for the opposite and perhaps worse scenario: That the designer strives to reduce weight and cost and therefore, accidentally, chooses an under achieving concept and thus induces large downstream cost if late redesign or retro modifications are necessary.

    This paper shows how optimization has been successfully used at Saab Aerospace as a tool that supports concept selection. The example shown is the choice of fuel transfer method for a ventral drop tank. The example also illustrates the impact of top-level requirements on low-level practicalities such as fuel system design.

  • 336.
    Gavel, Hampus
    et al.
    Linköping University, Department of Management and Engineering, Machine Design. Linköping University, The Institute of Technology.
    Krus, Petter
    Linköping University, Department of Management and Engineering, Machine Design. Linköping University, The Institute of Technology.
    Andersson, Johan
    Linköping University, Department of Mechanical Engineering, Machine Design. Linköping University, The Institute of Technology.
    Quantification of the Elements in the Relationship matrix: A conceptual study of Aircraft Fuel System2004In: 42nd AIAA Aerospace Sciences Meeting and Exhibit, Reno, USA, paper AIAA-2004-0538, 2004, no AIAA-2004-0538, p. 5244-5252Conference paper (Refereed)
    Abstract [en]

    This paper describes how the framework of thc house of quality and design structure matrices are used to visualizee dependencies between top level requirements and engineering design properties. It is also discussed how quantification of the matrix elements may increase the understanding of how the top-level requirements impacts the low-level design parameters. lndeed, history has shown that overlooking combinatory effects between subsystems and night conditions may become expensive. Not only in terms of not goning getting the sizing right but more so if an entirely wrong concept is chosen.

    This paper shows a matrix technique that has successfully been used at Saab and how this technique may facilitate the cconcept evaluation process of early fuel system design.

    The matrix method aids the designer to take alk the relevant aspects into account when evaluating a design. Use of the method will also increase the understanding of what top-level requirement or combination thereof, which drives the choice of one particular concept rather than the other. The understanding of how the top-level requiremEnts impacts low level design parameters such as pump size or pipe diameter will also increse.

  • 337.
    Gebremedhin, Alemayehu
    Linköping University, Department of Mechanical Engineering, Energy Systems. Linköping University, The Institute of Technology.
    The impact of a widened energy system boundary on cost effectiveness2000Licentiate thesis, monograph (Other academic)
    Abstract [en]

    This study describes the impact of widened system boundaries in the choice of heat generating plants, the total cost of the defined energy system and the use of combined heat and power (CHP) production plants. The economic and environmental benefits of co­ operation between public utilities and industries and the importance of enlarged system boundaries are shown in the different case-studies.

    The analysis was based on computer modelling of municipal and industrial energy systems. A user-friendly graphical interface program based on the linear programming model, MODEST, was developed as part of this study. The majority of the case-studies presented in this thesis were then performed with this application program.

    The various case-studies clearly indicate the cost reduction potential of co-operation. Both utilities and heat supplying industries benefit from this co-operation concerning heat supply. The cost saving potentials change from one case to another and depend on several factors.

    New plants within a sub-system appear to be attractive when this system is connected with other sub-systems within the extended system boundaries. In general, we can say that an extended system boundary leads normally to reduced total costs, more rational utilisation of plants, increased heat and electricity generation through the CHP plant and declining use of fossil fuels.

    The net present value of the maximum allowable investment cost for district-heating pipeline connections is roughly estimated when the cost for connection is not given or known. This cost can be used as a guideline to indicate whether connections should be considered or not.

  • 338.
    Gebremedhin, Alemayehu
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Mechanical Engineering, Energy Systems.
    Akkerman, H.
    Ottosson, Hans
    Linköping University, The Institute of Technology. Linköping University, Department of Mechanical Engineering.
    Energy System Analysis: Optimization of the Karlshamn Energy System, in the KEES Project2001Other (Other (popular science, discussion, etc.))
    Abstract [en]

        

  • 339.
    Gebremedhin, Alemayehu
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Mechanical Engineering, Energy Systems.
    Glad, Wiktoria
    Linköping University, Faculty of Arts and Sciences. Linköping University, The Tema Institute, Technology and Social Change.
    Gustafsson, Stig-Inge
    Linköping University, Department of Mechanical Engineering.
    Energianalys Solna. Forskningsrapport inom programmet Uthållig kommun.2004Report (Other academic)
  • 340.
    Gebremedhin, Alemayehu
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Mechanical Engineering, Energy Systems.
    Gustafsson, Stig-Inge
    Linköping University, The Institute of Technology. Linköping University, Department of Mechanical Engineering, Energy Systems.
    Glad, Wictoria
    Tema T Linköpings Universitet.
    Energisystemanalys Solna2004Report (Other academic)
  • 341.
    Gebremedhin, Alemayehu
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Mechanical Engineering, Energy Systems.
    Henning, Dag
    Linköping University, The Institute of Technology. Linköping University, Department of Mechanical Engineering, Energy Systems.
    Palm, Jenny
    Linköping University, Faculty of Arts and Sciences. Linköping University, The Tema Institute, Technology and Social Change.
    Energianalys Vingåker2006Report (Other academic)
  • 342.
    Gebremedhin, Alemayehu
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Mechanical Engineering, Energy Systems.
    Moshfegh, Bahram
    Linköping University, The Institute of Technology. Linköping University, Department of Mechanical Engineering, Energy Systems.
    Modelling and optimization of district heating and industrial energy system - An approach to a locally deregulated heat market2004In: International journal of energy research (Print), ISSN 0363-907X, E-ISSN 1099-114X, Vol. 28, no 5, p. 411-422Article in journal (Refereed)
    Abstract [en]

    Regions with densely concentration of industries and district heating systems (DHS) could be interesting study object from the light of an integrated heat market on local basis. System analysis with a widened system boundary could be used as an approach to evaluate the benefit of an integrated heat supply system. In this study, an energy system model consisting of totally seven different participants is designed and the optimization results of the system analysis are presented. With applied data and assumptions, the study shows that a significant amount of the heat demand within two sub-systems can be covered by heat supply from the heat market (the entire heat comes from two industries). Shadow prices, which can be used for heat pricing, indicate the advantage of an integrated system. The system cost reduction through integration and the availability of several actors with diverse energy supply system, makes the region under study an interesting area to prove a locally deregulated heat market.

  • 343.
    Gebremedhin, Alemayehu
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Mechanical Engineering, Energy Systems.
    Zinko, Heimo
    Linköping University, The Institute of Technology. Linköping University, Department of Mechanical Engineering, Energy Systems.
    Avoiding high return temperatures with absorption coolers in district heating systems2004In: 9th International Symposium on district heating and cooling,2004, 2004, p. 191-Conference paper (Refereed)
  • 344.
    Gibmeier, Jens
    et al.
    Institute of Materials Technology University of Kassel.
    Peng, Ru
    Linköping University, The Institute of Technology. Linköping University, Department of Mechanical Engineering, Engineering Materials.
    Odén, Magnus
    Linköping University, The Institute of Technology. Linköping University, Department of Mechanical Engineering, Engineering Materials.
    Scholtes, B
    Institute of Materials Technology University of Kassel.
    Residual Stress Distributions around Clinched Joints2002In: Materials Science Forum, ISSN 0255-5476, E-ISSN 1662-9752, Vol. 404-407, p. 617-622Article in journal (Refereed)
    Abstract [en]

    Clinching is a mechanical press joining method, which has become of growing interest in recent time since it has the potential to replace other conventional joining methods like e.g. spot welding. However, there still exists a lack of knowledge in terms of the mechanical behavior of clinched joints under quasistatic or cyclic loading. For that reason clinching is usually used for applications in structures which are not subjected to external loads. In particular the residual stress distribution in the vicinity of clinched joints and its influence on the mechanical behavior of the joints is unknown. Here diffraction methods are used for the determination of characteristic residual stress distributions in undismantled clinched samples. A combined residual stress determination by X-ray and neutron diffraction has been used to get a well-founded assessment of the residual stress distributions in the immediate vicinity of clinched joints. The residual stress analysis is supplemented by characterizations of the microstructures and the mechanical properties of single clinched joints. Two materials with different strain hardening behavior were used for clinching, a micro alloyed steel (ZStE340) and a non age hardenable aluminum base alloy (AlMg5). In addition two different common clinching techniques were applied - the TOX- [5] and the Eckold-technique [6]. Characteristic residual stress distributions were found for the combinations of clinching techniques and joined sheet materials investigated here. It has been determined that the clinching process induces predominantly compressive residual stresses inside the clinch and in the immediate vicinity of the clinch. The near surface residual stress distributions determined by X-ray diffraction measurements tend to reveal somewhat different residual stresses than measured by neutron diffraction, indicating a possible stress gradient through the sheet thickness. Further evaluation of the FWHM-values of the respective interference profiles shows that for both clinching techniques the largest amount of plastic deformation occurs in the clinch lock region.

  • 345.
    Gibmeier, Jens
    et al.
    Institute of Materials Technology University of Kassel.
    Rode, Nils
    Institute of Materials Technology University of Kassel.
    Peng, Ru
    Linköping University, The Institute of Technology. Linköping University, Department of Mechanical Engineering, Engineering Materials.
    Odén, Magnus
    Linköping University, The Institute of Technology. Linköping University, Department of Mechanical Engineering, Engineering Materials.
    Scholtes, B
    Institute of Materials Technology University of Kassel.
    Residual stress in clinched joints of metals2002Article in journal (Refereed)
    Abstract [en]

    Diffraction methods are used for the determination of characteristic residual stress (RS) distributions in undismantled clinched samples for the assessment of the influence of RS on the mechanical behaviour of clinched joints. While X-ray diffraction enables merely the determination of near-surface RS distributions, the higher penetration depth of neutron radiation allows the determination of triaxial RS states inside the material. In addition, the complex geometry of clinched joints restricts the application of X-ray RS analysis. Therefore a combined RS determination by X-ray and neutron diffraction has been used to obtain an expressive assessment of the RS distributions in the immediate vicinity of clinched joints. Two different materials with different mechanical behaviour were used for clinching, as well as two different common clinching techniques.

  • 346.
    Gong, Mei
    Linköping University, Department of Mechanical Engineering, Energy Systems. Linköping University, The Institute of Technology.
    Exergy analysis of a pulp and paper mill2005In: International journal of energy research (Print), ISSN 0363-907X, E-ISSN 1099-114X, Vol. 29, no 1, p. 79-93Article in journal (Refereed)
    Abstract [en]

    Different energy and exergy concepts and methods are presented and applied to a Swedish pulp and paper mill. Flow diagrams show that the exergy content is mostly much less than the energy content of the flows. The largest exergy losses appear in the boilers. Heating processes are highly exergy inefficient. A limited Life Cycle Exergy Analysis (LCEA) shows that the exergy output amounts to over 3 times the spent exergy as non-sustainable resources. By replacing the present use of non-sustainable resources, mostly fuel oil, the mill could move towards a truly sustainable process.

  • 347.
    Gong, Mei
    Linköping University, Department of Mechanical Engineering, Energy Systems. Linköping University, The Institute of Technology.
    Using exergy and optimization models to improve industrial energy systems towards sustainability2004Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    With finite natural resources and large energy demands in the world, a sustainable development approach becomes increasingly important in the improvement of energy systems. The concept of sustainability is examined with relation to exergy flows on the earth. The present industrial society is obviously not sustainable. The main aim of this study is to analyze and improve industrial energy systems towards an increased sustainability.

    Exergy analysis is used for evaluating energy systems and for guiding efficiency-improvement efforts. An existing optimization method is improved and applied to an energy system in order to maximize its economic feasibility and profitability. Life cycle analysis based on exergy is applied in order to further guide towards sustainable development. This thesis offers tools to better evaluate energy systems with regard to physical resource use, economy and environment. These tools are particularly useful for decision-making in long-term plarming.

    The concepts and methods presented are useful in the design and optimization of more sustainable energy systems, particularly in industrial processes. A typical Swedish industry, a pulp and board mill, is examined using an improved optimization method together with the exergy method. The main cause of the low exergy efficiency in the mill is irreversibility of combustion and of heat transfer in the steam generator. The change in the price of electricity has a greater effect on the energy cost than the change in the price of fuel, which means a unified European electricity market has large impact on the Swedish industry. Increasing efficiency of processes usually minimizes environmental damage and maximizes economic benefits. In spite of increasing the exergy loss switching from fossil fuel to bio-fuels can decrease the net CO2 emission as well as the energy cost, and is a step towards increased sustainability. The investments in an oil-bark boiler, evaporation plant and recovery boiler give a good supply of sustainable resources, a reduction of environmental impact, and both energy and economical saving. In addition, with replacing the present evaporation plant with the non-conventional one, even more benefits could be achieved. Still, there are more potential for further improvement in the mill.

    List of papers
    1. On exergy and sustainable development - Part 1: conditions and concepts
    Open this publication in new window or tab >>On exergy and sustainable development - Part 1: conditions and concepts
    2001 (English)In: Exergy: An International Journal, ISSN 1634-7803, E-ISSN 1164-0235, Vol. 1, no 3, p. 128-145Article in journal (Refereed) Published
    Abstract [en]

    The future of life on our planet is a matter of great concern. This paper is based on a vision of sustainable development. It is divided into two parts. The first part introduces conditions and concepts that are of importance for sustainable development. Environmental conditions in terms of causes and effects of emissions, the concept of exergy as a physical measure of difference or contrast and a number of different exergy forms common in nature are presented. Emissions and pollutants are differences in the environment, thus effecting the environment. Exergy is a suitable measure of these differences. The concept of sustainability is examined with relation to exergy flows on the earth. Part 2 of this paper introduces methods based on presented concepts and applies these to real systems. Exergy is applied to emissions to the environment by case studies in order to describe and evaluate its values and limitations as an ecological indicator. Exergy is considered as a useful ecological indicator by reference to the literature in the field.

    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-86944 (URN)10.1016/S1164-0235(01)00020-6 (DOI)
    Available from: 2013-01-08 Created: 2013-01-08 Last updated: 2017-12-06
    2. On exergy and sustainable development - Part 2: indicators and methods
    Open this publication in new window or tab >>On exergy and sustainable development - Part 2: indicators and methods
    2001 (English)In: Exergy: An International Journal, ISSN 1634-7803, E-ISSN 1164-0235, Vol. 1, no 4, p. 217-233Article in journal (Refereed) Published
    Abstract [en]

    This second part is the continuation of Wall and Gong [Exergy Internat. J. 1 (3) (2001), in press]. This part is an overview of a number of different methods based on concepts presented in the first part and applies these to real systems. A number of ecological indicators will be presented and the concept of sustainable development will be further clarified. The method of Life Cycle Exergy Analysis will be presented. Exergy will be applied to emissions into the environment by case studies in order to describe and evaluate its values and limitation as an ecological indicator. Exergy is concluded to be a suitable ecological indicator and future research in this area is strongly recommended.

    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-86945 (URN)10.1016/S1164-0235(01)00030-9 (DOI)
    Available from: 2013-01-08 Created: 2013-01-08 Last updated: 2017-12-06
    3. 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
    Keywords
    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
    4. Optimization of industrial energy systems by incorporating feedback loops into the MIND method
    Open this publication in new window or tab >>Optimization of industrial energy systems by incorporating feedback loops into the MIND method
    2003 (English)In: Energy, ISSN 0360-5442, E-ISSN 1873-6785, Vol. 28, no 15, p. 1655-1669Article in journal (Refereed) Published
    Abstract [en]

    The MIND (Method for analysis of INDustrial energy system) method has been developed for multi-period cost optimization of industrial energy systems. Existing industrial processes can be represented at the desired level of accuracy, i.e. one modeling unit may represent a part of the production process or the whole plant. The optimization method includes both energy and material flows. Nonlinear relations, energy conversion efficiencies and investment costs are linearized by mixed-integer linear programming. A flexible time-scale facilitates the performance of long- and short-term analyses. In order to meet the requirements with regard to sustainable development, the recycling of energy and material flows is becoming more common in many industrial processes. The recycling or reuse of energy and material is managed by feedback loops, which are incorporated into the original MIND method to improve the model and reduce the calculation time. The improved MIND/F method (MIND method with feedback loops) model is applied to a pulp and paper mill in Sweden. A comparison between the original MIND method with manual handling of the feedback loops and the MIND/F method gives highly satisfactory results. Cost optimization using the improved MIND method is well within the given accuracy and computer time and manual calculation time are both reduced considerably. The reuse of energy and material resources is not only an economic advantage, but also implies a reduction of the environmental impact.

    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-46367 (URN)10.1016/S0360-5442(03)00170-1 (DOI)
    Available from: 2009-10-11 Created: 2009-10-11 Last updated: 2017-12-13
    5. Exergy analysis of a pulp and paper mill
    Open this publication in new window or tab >>Exergy analysis of a pulp and paper mill
    2005 (English)In: International journal of energy research (Print), ISSN 0363-907X, E-ISSN 1099-114X, Vol. 29, no 1, p. 79-93Article in journal (Refereed) Published
    Abstract [en]

    Different energy and exergy concepts and methods are presented and applied to a Swedish pulp and paper mill. Flow diagrams show that the exergy content is mostly much less than the energy content of the flows. The largest exergy losses appear in the boilers. Heating processes are highly exergy inefficient. A limited Life Cycle Exergy Analysis (LCEA) shows that the exergy output amounts to over 3 times the spent exergy as non-sustainable resources. By replacing the present use of non-sustainable resources, mostly fuel oil, the mill could move towards a truly sustainable process.

    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-29317 (URN)10.1002/er.1041 (DOI)14614 (Local ID)14614 (Archive number)14614 (OAI)
    Available from: 2009-10-09 Created: 2009-10-09 Last updated: 2017-12-13
    6. Coordination of exergy analysis and the MIND method - applied to a pulp and board mill
    Open this publication in new window or tab >>Coordination of exergy analysis and the MIND method - applied to a pulp and board mill
    2004 (English)In: International Journal of Exergy, ISSN 1742-8297, E-ISSN 1742-8300, Vol. 1, no 3, p. 289-302Article in journal (Refereed) Published
    Abstract [en]

    The MIND (Method for analysis of INDustrial energy systems) method has been developed for cost optimisation of industrial energy systems, mainly with regard to quantities of energy. Exergy analysis reveals losses, efficiencies and possible improvements. These methods can be combined in order to improve industrial energy systems. In this paper, a Swedish pulp and board mill is used as a case study. The efficiencies of the processes in the mill are evaluated using exergy analysis. The most exergy inefficient processes are indicated and some improvements are suggested. This case study shows that it is the boilers and the evaporation plant that are the most inefficient processes, with efficiencies down to 29%. Different investment alternatives for these processes are studied and cost optimisation is achieved using the MIND method. The study shows that the energy costs can be reduced by up to 15 million Euros per year while the exergy efficiency can be improved by up to 14%. The combined approach shows that the energy cost-efficient alternatives are also usually exergy efficient.

    Keywords
    efficiency; energy; exergy; industrial energy system; optimisation; pulp and paper
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-22918 (URN)10.1504/IJEX.2004.005558 (DOI)2273 (Local ID)2273 (Archive number)2273 (OAI)
    Available from: 2009-10-07 Created: 2009-10-07 Last updated: 2017-12-13
  • 348.
    Gong, Mei
    et al.
    Linköping University, Department of Mechanical Engineering, Energy Systems. Linköping University, The Institute of Technology.
    Karlsson, Magnus
    Linköping University, Department of Mechanical Engineering, Energy Systems. Linköping University, The Institute of Technology.
    Coordination of exergy analysis and the MIND method - applied to a pulp and board mill2004In: International Journal of Exergy, ISSN 1742-8297, E-ISSN 1742-8300, Vol. 1, no 3, p. 289-302Article in journal (Refereed)
    Abstract [en]

    The MIND (Method for analysis of INDustrial energy systems) method has been developed for cost optimisation of industrial energy systems, mainly with regard to quantities of energy. Exergy analysis reveals losses, efficiencies and possible improvements. These methods can be combined in order to improve industrial energy systems. In this paper, a Swedish pulp and board mill is used as a case study. The efficiencies of the processes in the mill are evaluated using exergy analysis. The most exergy inefficient processes are indicated and some improvements are suggested. This case study shows that it is the boilers and the evaporation plant that are the most inefficient processes, with efficiencies down to 29%. Different investment alternatives for these processes are studied and cost optimisation is achieved using the MIND method. The study shows that the energy costs can be reduced by up to 15 million Euros per year while the exergy efficiency can be improved by up to 14%. The combined approach shows that the energy cost-efficient alternatives are also usually exergy efficient.

  • 349.
    Gong, Mei
    et al.
    Linköping University, Department of Mechanical Engineering, Energy Systems. Linköping University, The Institute of Technology.
    Karlsson, Magnus
    Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, The Institute of Technology.
    Söderström, Mats
    Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, The Institute of Technology.
    Industry and the energy market - optimal choice of measures using the MIND method2002In: CRIS Conference on Power Systems and Communications Infrastructures for the future, 2002, China: CRIS, International Institute for Critical Infrastructures , 2002Conference paper (Refereed)
    Abstract [en]

    No abstract available.

  • 350.
    Gong, Mei
    et al.
    Linköping University, Department of Mechanical Engineering, Energy Systems. Linköping University, The Institute of Technology.
    Wall, Göran
    Independent Researcher, Mölndal, Sweden.
    On exergy and sustainable development - Part 2: indicators and methods2001In: Exergy: An International Journal, ISSN 1634-7803, E-ISSN 1164-0235, Vol. 1, no 4, p. 217-233Article in journal (Refereed)
    Abstract [en]

    This second part is the continuation of Wall and Gong [Exergy Internat. J. 1 (3) (2001), in press]. This part is an overview of a number of different methods based on concepts presented in the first part and applies these to real systems. A number of ecological indicators will be presented and the concept of sustainable development will be further clarified. The method of Life Cycle Exergy Analysis will be presented. Exergy will be applied to emissions into the environment by case studies in order to describe and evaluate its values and limitation as an ecological indicator. Exergy is concluded to be a suitable ecological indicator and future research in this area is strongly recommended.

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