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  • 1.
    Diepenbrock, Stefan
    et al.
    University of Münster.
    Praßni, Jörg-Stefan
    University of Münster.
    Lindemann, Florian
    University of Münster.
    Bothe, Hans-Werner
    University Hospital Münster.
    Ropinski, Timo
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
    2010 IEEE Visualization Contest Winner: Interactive Planning for Brain Tumor Resections2011In: IEEE Computer Graphics and Applications, ISSN 0272-1716, E-ISSN 1558-1756, Vol. 31, no 5, 6-13 p.Article in journal (Other academic)
    Abstract [en]

    n/a

  • 2.
    Rodríguez-Vila, Borja
    et al.
    Bioengineering and Telemedicine Group, Universidad Politécnica de Madrid Spain.
    Pettersson, Johanna
    Linköping University, Department of Biomedical Engineering, Medical Informatics. Linköping University, Center for Medical Image Science and Visualization (CMIV). Linköping University, The Institute of Technology.
    Borga, Magnus
    Linköping University, Department of Biomedical Engineering, Medical Informatics. Linköping University, Center for Medical Image Science and Visualization (CMIV). Linköping University, The Institute of Technology.
    García-Vicente, Feliciano
    Medical Physics, Radiotherapy Department, University Hospital La Princesa Spain.
    Gómez, Enrique J.
    Bioengineering and Telemedicine Group, Universidad Politécnica de Madrid Spain.
    Knutsson, Hans
    Linköping University, Department of Biomedical Engineering, Medical Informatics. Linköping University, The Institute of Technology. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    3D deformable registration for monitoring radiotherapy treatment in prostate cancer2007In: Image Analysis: 15th Scandinavian Conference, SCIA 2007, Aalborg, Denmark, June 10-14, 2007, Berlin/Heidelberg, Germany: Springer Berlin/Heidelberg, 2007, 750-759 p.Conference paper (Refereed)
    Abstract [en]

    Two deformable registration methods, the Demons and the Morphon algorithms, have been used for registration of CT datasets to evaluate their usability in radiotherapy planning for prostate cancer. These methods were chosen because they can perform deformable registration in a fully automated way. The experiments show that for intrapatient registration both of the methods give useful results, although some differences exist in the way they deform the template. The Morphon method has, however, some advantageous compared to the Demons method. It is invariant to the image intensity and it does not distort the deformed data. The conclusion is therefore to recommend the Morphon method as a registration tool for this application. A more flexible regularization model is needed, though, in order to be able to catch the full range of deformations required to match the datasets.

  • 3.
    Steen, Alexander
    et al.
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, The Institute of Technology.
    Widegren, Marcus
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, The Institute of Technology.
    3D Visualization for Pre-operative Planning of Orthopedic Surgery2013Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This report presents a master thesis on 3D visualization for pre-operation planning of orthopedic surgery done for Sectra Medical Systems AB. The focus is on visualizing clinically relevant data for planning a Total Hip Replacement (THR). The thesis includes a pre-study and the implementation of a prototype using the Sectra IDS7 workstation.

  • 4.
    Hernell, Frida
    et al.
    Linköping University, Department of Science and Technology, Visual Information Technology and Applications (VITA). Linköping University, Center for Medical Image Science and Visualization (CMIV). Linköping University, The Institute of Technology.
    Ynnerman, Anders
    Linköping University, Department of Science and Technology, Visual Information Technology and Applications (VITA). Linköping University, The Institute of Technology. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    Smedby, Örjan
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Medical Radiology. Östergötlands Läns Landsting, Centre for Medical Imaging, Department of Radiology UHL. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    A blending technique for enhanced depth perception in medical x-ray vision applications2007In: Medicine Meets Virtual Reality 15 / [ed] James D. Westwood, Randy S. Haluck, Helene M. Hoffman, Greg T. Mogel, Roger Phillips, Richard A. Robb, Kirby G. Vosburgh, IOS Press, 2007, Vol. 125, 176-178 p.Conference paper (Refereed)
    Abstract [en]

    Depth perception is a common problem for x-ray vision in augmented reality applications since the goal is to visualize occluded and embedded objects. In this paper we present an x-ray vision blending method for neurosurgical applications that intensifies the interposition depth cue in order to achieve enhanced depth perception. The proposed technique emphasizes important structures, which provides the user with an improved depth context.

  • 5.
    Edström, Kristina
    et al.
    School of Education and Communication in Engineering Science, KTH Royal Institute of Technology, Stockholm, Sweden.
    Kolmos, Anette
    Department of Development and Planning, Aalborg University, Aalborg, Denmark.
    Malmi, Lauri
    Department of Computer Science, Aalto University, Helsinki, Finland.
    Bernhard, Jonte
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Andersson, Pernille
    LearningLab DTU, Technical University of Denmark, Kgs. Lyngby, Denmark.
    A bottom-up strategy for establishment of EER in three Nordic countries: The role of networks2016In: European Journal of Engineering Education, ISSN 0304-3797, E-ISSN 1469-5898Article in journal (Refereed)
    Abstract [en]

    This paper investigates the emergence of an engineering education research (EER) community in three Nordic countries: Denmark, Finland and Sweden. First, an overview of the current state of Nordic EER authorship is produced through statistics on international publication. Then, the history of EER and its precursor activities is described in three national narratives. These national storylines are tied together in a description of recent networking activities, aiming to strengthen the EER communities on the Nordic level. Taking these three perspectives together, and drawing on concepts from community of practice theory, network theory and learning network theory, we discuss factors behind the differences in the countries, and draw some conclusions about implications for networking activities in a heterogeneous community. Further, we discuss the role of networks for affording a joint identity.

  • 6.
    Quast, Ulrich
    et al.
    Ex University Hospital, Germany.
    Kaulich, Theodor W.
    University Hospital, Germany.
    Alvarez-Romero, Jose T.
    ININ, Mexico.
    Carlsson Tedgren, Åsa
    Linköping University, Department of Medical and Health Sciences, Division of Radiological Sciences. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Surgery, Orthopaedics and Cancer Treatment, Department of Radiation Physics. Karolinska University Hospital, Sweden.
    Enger, Shirin A.
    McGill University, Canada.
    Medich, David C.
    Worcester Polytech Institute, MA 01609 USA.
    Mourtada, Firas
    Helen F Graham Cancer Centre and Research Institute, DE 19713 USA.
    Perez-Calatayud, Jose
    University Hospital La Fe, Spain; Clin Benidorm, Spain.
    Rivard, Mark J.
    Tufts University, MA 02111 USA.
    Abu Zakaria, G.
    University of Cologne, Germany; Gono University, Bangladesh.
    A brachytherapy photon radiation quality index Q(BT) for probe-type dosimetry2016In: Physica medica (Testo stampato), ISSN 1120-1797, E-ISSN 1724-191X, Vol. 32, no 6, 741-748 p.Article in journal (Refereed)
    Abstract [en]

    Introduction: In photon brachytherapy (BT), experimental dosimetry is needed to verify treatment plans if planning algorithms neglect varying attenuation, absorption or scattering conditions. The detectors response is energy dependent, including the detector material to water dose ratio and the intrinsic mechanisms. The local mean photon energy E(r) must be known or another equivalent energy quality parameter used. We propose the brachytherapy photon radiation quality index Q(BT) ((E) over bar), to characterize the photon radiation quality in view of measurements of distributions of the absorbed dose to water, D-w, around BT sources. Materials and methods: While the external photon beam radiotherapy (EBRT) radiation quality index Q(EBRT) ((E) over bar) = TPR1020((E) over bar) is not applicable to BT, the authors have applied a novel energy dependent parameter, called brachytherapy photon radiation quality index, defined as Q(BT) ((E) over bar) = D-prim(r = 2 cm; theta(0) = 90 degrees)/D-prim(r(0) = 1 cm; theta(0) = 90 degrees), utilizing precise primary absorbed dose data, D-prim, from source reference databases, without additional MC-calculations. Results and discussion: For BT photon sources used clinically, Q(BT) ((E) over bar) enables to determine the effective mean linear attenuation coefficient (mu) over bar (E) and thus the effective energy of the primary photons E-prim(eff)(r(0), theta(0)) at the TG-43 reference position P-ref (r(0) = 1 cm; theta(0) = 90 degrees) being close to the mean total photon energy (E) over bar (tot)(r(0), theta(0)). If one has calibrated detectors, published (E) over bar (tot)(r) and the BT radiation quality correction factor k(Q, Q0)(BT) ((E) over bar, r, theta) for different BT radiation qualities Q and Q(0), the detectors response can be determined and D-w(r, theta) measured in the vicinity of BT photon sources. Conclusions: This novel brachytherapy photon radiation quality index Q(BT) characterizes sufficiently accurate and precise the primary photon` s penetration probability and scattering potential. (C) 2016 Published by Elsevier Ltd on behalf of Associazione Italiana di Fisica Medica.

  • 7.
    van der Zijpp, Teatske Johanna
    et al.
    Fontys University of Applied Sciences, Faculty of Nursing, Eindhoven, The Netherlands.
    Niessen, Theo
    Fontys University of Applied Sciences, Faculty of Nursing, Eindhoven, The Netherlands.
    Eldh, Ann Catrine
    Health and Social Studies, Dalarna University, Falun, Sweden; Division of Nursing, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm, Sweden.
    Hawkes, Claire
    Warwick Clinical Trials Unit, Division of Health Sciences, Warwick Medical School, The University of Warwick, Coventry, UK.
    McMullan, Christel
    Institute of Applied Health Research, Murray Learning Centre, University of Birmingham, Birmingham, UK.
    Mockford, Carole
    Royal College of Nursing Research Institute, Department of Health Sciences, Warwick Medical School, University of Warwick, Coventry, UK.
    Wallin, Lars
    Health and Social Studies, Dalarna University, Falun, Sweden; Division of Nursing, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm, Sweden.
    McCormack, Brendan
    School of Health Sciences, Queen Margaret University, East Lothian,UK.
    Rycroft-Malone, Jo
    Bangor University, UK, and School of Healthcare Sciences, Bangor, UK.
    Seers, Kate
    Division of Health Sciences, Warwick Medical School, University of Warwick, Coventry, UK.
    A Bridge Over Turbulent Waters: Illustrating the Interaction Between Managerial Leaders and Facilitators When Implementing Research Evidence.2016In: Worldviews on Evidence-Based Nursing, ISSN 1545-102X, E-ISSN 1741-6787, Vol. 13, no 1, 25-31 p.Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: Emerging evidence focuses on the importance of the role of leadership in successfully transferring research evidence into practice. However, little is known about the interaction between managerial leaders and clinical leaders acting as facilitators (internal facilitators [IFs]) in this implementation process.

    AIMS: To describe the interaction between managerial leaders and IFs and how this enabled or hindered the facilitation process of implementing urinary incontinence guideline recommendations in a local context in settings that provide long-term care to older people.

    METHODS: Semistructured interviews with 105 managers and 22 IFs, collected for a realist process evaluation across four European countries informed this study. An interpretive data analysis unpacks interactions between managerial leaders and IFs.

    RESULTS: This study identified three themes that were important in the interactions between managerial leaders and IFs that could hinder or support the implementation process: "realising commitment"; "negotiating conditions"; and "encouragement to keep momentum going." The findings revealed that the continuous reciprocal relationships between IFs and managerial leaders influenced the progress of implementation, and could slow the process down or disrupt it. A metaphor of crossing a turbulent river by the "building of a bridge" emerged as one way of understanding the findings.

    LINKING EVIDENCE TO ACTION: Our findings illuminate a neglected area, the effects of relationships between key staff on implementing evidence into practice. Relational aspects of managerial and clinical leadership roles need greater consideration when planning guideline implementation and practice change. In order to support implementation, staff assigned as IFs as well as stakeholders like managers at all levels of an organisation should be engaged in realising commitment, negotiating conditions, and keeping momentum going. Thus, communication is crucial between all involved.

  • 8.
    Hallander, Ingrid
    Linköping University, Department of Mechanical Engineering, Fluid and Mechanical Engineering Systems. Linköping University, The Institute of Technology.
    A broad perspective on life cycle considerations in product development2004Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    For products with long life cycles, operational and support costs represent a significant part of the total cost for the product. Moreover, such products frequently tend to be complex and contain a mixture of both mature. stable technology with bng life cycles and new technology with short life cycles. lt is therefore of great interest to industry to determine how to take these factors into consideration in an efficient way during product development.

    Another factor that affects product development for these and other kinds of products with shorter life cycles is interest in taking a wider view of the end-user or customer scenario, for instance by offering support and after sales services for the products. All these interests drive the demand to consider life cycle related issues in product development, not just life cycle cost. This also makes a life cycle perspective interesting for fums that produce products with shorter life cycles than the ones studied here through the opportunity for after market sales and services.

    This research has been explorative, aiming to understand how firms manage to take life cycle related demands into consideration during product development. The aim was to expand from a cost oriented focus to a wider focus, a value oriented focus, here called life cycle value. The dominant question has been "how" life cycle related demands are considered, focusing on barriers to and enablers for this. Equally important has been to determine the implication of life cycle value for different firms and industries and to find out where value is added in product development. A combination of a quantitative and qualitative research approach has been used to collect empirical data.

    One important finding was that there is an interest to deliver a solution to the customer rather than just a product, to consider customer revenue. This adds a new perspective to the implication of life cycle value, moving from a life cycle cost scenario to a life cycle cost versus revenue scenario. The results fom cases were categorized into six main attributes. These attributes were considered to be very influential and important for the ability to take life cycle perspective into account during product development.

    • Holistic Perspective
    • Requirements & Metrics
    • Leadership & Management/Knowledge management
    • Tools & Methods
    • Organizational Factors
    • Enterprise Relationships

    Within each of these attributes, several practices and lessons learned were identified. Some of the results are also worth investigating further in continued research:

    • Requirements formulation and management is considered to be critical. Well defined and clearly stated demands are key to taking life cycle issues into account due to the difficulty of incorporating life cycle related demands into the product. Nonetheless, balancing these demands against others is perceived to be difficult, and there is a clear need for tools, methods or models to support decision-making in this context.
    • The incorporation of new technology and services is another field of interest to industry. Organizational support and planning for technology insertion and new innovations and services into existing products and product lines are needed.
    • The organizational support to balance specialization and integration in a product development context, with a long-term focus
    • The effect of a transfer from delivering a product to delivering product and support services to the organization.
    List of papers
    1. Life cycle value in product development: a case study in the transportation industry
    Open this publication in new window or tab >>Life cycle value in product development: a case study in the transportation industry
    2003 (English)In: DS 31: Proceedings of ICED 03, the 14th International Conference on Engineering Design, Stockholm, Stockholm, Sweden: ICED'03 , 2003, 417-418 p.Conference paper, Published paper (Other academic)
    Abstract [en]

    Several factors prevent enterprises from having a holistic perspective during product development. Important aspects include increased product complexity and significant uncertainty with regard to technology. For products with a long life cycle this is extremely important since development and life cycle costs are high. The combination of complexity of system design and the limits of individual human comprehension typically make it difficult to envision a best value solution.

    In an attempt to encircle a more holistic perspective of value, the concept of Life Cycle Value has evolved within the Lean Aerospace Initiative, LAI. The implication of this is development of products incorporating life cycle and long-term focus including cost and performance and reliability factors. A similar perspective has evolved within the Lean Aircraft Research Program, LARP, in Sweden.

    This paper contributes a new study of how life cycle aspects are taken into consideration in a large corporation in the transportation industry. The purpose of the research was to examine relative contributions to product development and determine factors that significantly promote the ability to consider the life cycle perspective. The results will be discussed with respect to tools, methods, requirements, metrics, leadership and other organizational factors, innovation, and enterprise relationships.

    Place, publisher, year, edition, pages
    Stockholm, Sweden: ICED'03, 2003
    Keyword
    Life cycle, value, product development, transportation industry
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-36398 (URN)31246 (Local ID)1-904670-00-8 (ISBN)31246 (Archive number)31246 (OAI)
    Conference
    ICED 03, the 14th International Conference on Engineering Design, Stockholm
    Available from: 2009-10-10 Created: 2009-10-10 Last updated: 2013-12-03
    2. Lifecycle value framework for tactical aircraft product development
    Open this publication in new window or tab >>Lifecycle value framework for tactical aircraft product development
    2001 (English)Conference paper, Published paper (Other academic)
    Abstract [en]

    Due to a dramatic reduction in defense procurement, the benchmark for developing new defense systems today is performance at an affordable cost. In an attempt to encircle a more holistic perspective of value, lifecycle value has evolved as a concept within the Lean Aerospace Initiative, LAI. The implication of this is development of products incorporating lifecycle and long-term focus instead of a shortsighted cost cutting focus. The interest to reduce total cost of ownership while still improving performance, availability, and sustainability, other dimensions taken into account within the lifecycle value approach, falls well within this context. Several factors prevent enterprises from having a holistic perspective during product development. Some important aspects are increased complexity of the products and significant technological uncertainty. The combination of complexity in system design and the limits of individual human comprehension typically prevent a best value solution to be envisioned. The purpose of this research was to examine relative contributions in product development and determine factors that significantly promote abilities to consider and achieve lifecycle value. This paper contributes a maturity matrix based on important practices and lessons learned through extensive interview based case studies of three tactical aircraft programs, including experiences from more than 100 interviews.

    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-102199 (URN)
    Conference
    2001 Eleventh Annual International Symposium, Melbourne, Australia, 1-5 July 2001
    Available from: 2013-12-03 Created: 2013-12-03 Last updated: 2013-12-03
  • 9.
    Patel, Mikael
    et al.
    Ericsson AB, Linköping, Sweden.
    Borg, Andreas
    Linköping University, Department of Computer and Information Science, PELAB - Programming Environment Laboratory. Linköping University, The Institute of Technology.
    Sandahl, Kristian
    Linköping University, Department of Computer and Information Science. Linköping University, Department of Computer and Information Science, PELAB - Programming Environment Laboratory.
    A Case Study in Assessing and Improving Capacity Using an Anatomy of Good Practice2007In: The 6th joint meeting of the European Software Engineering Conference and the ACM SIGSOFT Symposium on the Foundations of Software Engineering (ESEC/FSE 2007), Dubrovnik, Croatia, New York: ACM , 2007, 509-512 p.Conference paper (Refereed)
    Abstract [en]

    Capacity in telecommunication systems is highly related to operator revenue. As a vendor of such systems, Ericsson AB is continuously improving its processes for estimating, specifying, tuning, and testing the capacity of delivered systems. In order to systematize process improvements Ericsson AB and Linköping University joined forces to create an anatomy of Capacity Sub Processes (CSPs). The anatomy is the result of an interview series conducted to document good practices amongst organizations active in capacity improvement. In this paper we analyze four different development processes in terms of how far they have reached in their process maturity according to our anatomy and show possible improvement directions. Three of the processes are currently in use at Ericsson, and the fourth is the OpenUP/Basic process which we have used as a reference process in earlier research. We also include an analysis of the observed good practices. The result mainly confirms the order of CSPs in the anatomy, but we need to use our information of the maturity of products and the major life cycle in the organization in order to fully explain the role of the anatomy in planning of improvements.

  • 10.
    Eliasson, Karolina
    Linköping University, Department of Computer and Information Science, CASL - Cognitive Autonomous Systems Laboratory. Linköping University, The Institute of Technology.
    A case-based approach to dialogue systems2010In: Journal of experimental and theoretical artificial intelligence (Print), ISSN 0952-813X, E-ISSN 1362-3079, Vol. 22, no 1, 23-51 p.Article in journal (Refereed)
    Abstract [en]

    We describe an approach to integrate dialogue management, machine-learning and action planning in a system for dialogue between a human and a robot. Case-based techniques are used because they permit life-long learning from experience and demand little prior knowledge and few static hand-written structures. This approach has been developed through the work on an experimental dialogue system, called CEDERIC, that is connected to an unmanned aerial vehicle (UAV). A single case base and case-based reasoning engine is used both for understanding and for planning actions by the UAV. Dialogue experiments both with experienced and novice users, where the users have solved tasks by dialogue with this system, showed very adequate success rates.

  • 11.
    Andriolo, Alessandro
    et al.
    University of Padova, Italy.
    Battini, Dania
    University of Padova, Italy.
    Grubbström, Robert W.
    Linköping University, Department of Management and Engineering, Production Economics. Linköping University, The Institute of Technology.
    Persona, Alessandro
    University of Padova, Italy.
    Sgarbossa, Fabio
    University of Padova, Italy.
    A century of evolution from Harriss basic lot size model: Survey and research agenda2014In: International Journal of Production Economics, ISSN 0925-5273, Vol. 155, 16-38 p.Article in journal (Refereed)
    Abstract [en]

    Determining the economic lot size has always represented one of the most important issues in production planning. This problem has long attracted the attention of researchers, and several models have been developed to meet requirements at minimum cost. In this paper we explore and discuss the evolution of these models during one hundred years of history, starting from the basic model developed by Harris in 1913, up to today. Following Harriss work, a number of researchers have devised extensions that incorporate additional considerations. The evolution of EOQ theory strongly reflects the development of industrial systems over the past century. Here we outline all the research areas faced in the past by conducting a holistic analysis of 219 selected journal papers and trying to give a comprehensive view of past work on the EOQ problem. Finally, a new research agenda is proposed and discussed.

  • 12.
    Elfving, Tommy
    et al.
    Linköping University, Department of Mathematics, Scientific Computing. Linköping University, The Institute of Technology.
    Nikazad, Touraj
    Dept. of Mathematics, Iran Uv of Science and Technology.
    Popa, Constantin
    Faculty of Math. and Comp. Science, Ovidius uv. Romania.
    A Class of Iterative Methods: Semi-Convergence, Stopping Rules, Inconsistency, and Constraining2010In: Biomedical Mathematics: Promising Directions in Imaging,Therapy Planning and Inverse Problems / [ed] Y. Censor, M. Jiang and G. Wang, Madison, Wi, USA: Medical Physics Publishing , 2010, 157-184 p.Chapter in book (Refereed)
    Abstract [en]

    This book brings together 27 state-of-the-art research and review papers by leading experts and practitioners in mathematical methods in biomedical imaging, in intensity-modulated radiation therapy (IMRT) and in optimization and inverse problems. These papers were presented at the Huangguoshu International Interdisciplinary Conference on Biomedical Mathematics Promising Directions in Imaging, Therapy Planning, and Inverse Problems November 3 9, 2008 in China. The emphasis is on trying to discover relations and connections between these fields that will enhance progress in each of them. As this volume shows, applicable mathematical work in these fields goes hand-in-hand with real-world applications and the mutual technology transfers between them leads to further progress. The topics covered here include mathematical aspects and practical problems in current major and emerging technologies in diagnostic and therapeutic medicine and biology research. The contributed work signifies the interdisciplinary cooperation between mathematicians and scientists from medical physics, engineering, clinical medicine, and biology that leads to mathematically based better solutions of practical problems in biomedical imaging and IMRT.

  • 13.
    Desai, Avni
    et al.
    Linköping University, Department of Management and Engineering, Environmental Technology and Management. Linköping University, Faculty of Science & Engineering.
    Widgren, Maria
    Linköping University, Department of Management and Engineering, Environmental Technology and Management. Linköping University, Faculty of Science & Engineering.
    A Collaboration in Product Service System for Telecom Networks: An "Orange and Ericsson case" study2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The purpose of the research is to study the “Orange and Ericsson case” while developing the method Actors and System Map. The interaction between actors within Ericsson’s Device Connection Platform is investigated in order to identify improvement opportunities in the interaction between the provider and the customer. To answer the purpose the following research questions was formulated:

    RQ1)  What type of actors may be involved in a telecom related IPSO?

    RQ2)  How can the connections between actors in the telecom related IPSO be illustrated?

    RQ3)  How can the Actors and System Map method be refined?

    In order to answer the research questions different methodologies were used for the analysing process. The research started with a widespread literature study to collect knowledge related to the area of Product Service System (PSS) and methodologies for identifying how actors interact with one another. Studying different mapping methods the conclusion was made that Actors and System Map was most suitable for this study.

    In the methodology background the previous selected method, Actors and System Map from an Integrated Product Service Offering (IPSO) perspective, was examined in order to be able to refine and improve the mapping method. Actors Map provides a visual and clear overview of the actors involved while a System Map shows the information flows and activities between the actors.

    To understand the interaction between the two companies, the definition of IPSO and the importance of value-based selling for a service offering are described in the theory background. Also, different ways of looking at a business model within the telecommunication industry is presented.

    Obtaining information regarding making an Actors Map and a System Map an improved mapping method was refined. The adaption of the method was divided into eight steps. The refined Actors Maps of the DCP shows the actors involved, how they are connected and their main assignments from each respondent’s point of view at Ericsson. The refined System Map shows what kind of information is transferred between the actors within the companies and between Orange and Ericsson. Both maps delivered as a decision basis will help identification of non-value giving links and non-optimal distances in the information flow for both companies.

  • 14.
    Murphy, Robin
    et al.
    Texas A&M University.
    Kleiner, Alexander
    Linköping University, Department of Computer and Information Science, KPLAB - Knowledge Processing Lab. Linköping University, The Institute of Technology.
    A Community-Driven Roadmap for the Adoption of Safety Security and Rescue Robots2013In: Safety, Security, and Rescue Robotics (SSRR), 2013 IEEE International Symposium on, IEEE conference proceedings, 2013, 1-5 p.Conference paper (Refereed)
    Abstract [en]

    The IEEE Safety, Security, and Rescue Robotics community has created a roadmap for producing unmanned systems that could be adopted by the Public Safety sector within 10 years, given appropriate R&D investment especially in human-robot interaction and perception. The five applications expected to be of highest value to the Public Safety community, highest value first, are: assisting with routine inspection of the critical infrastructure, “chronic emergencies” such as firefighting, hazardous material spills, port inspection, and damage estimation after a disaster. The technical feasibility of the applications were ranked, with the most attractive scenario, infrastructure inspection, rated as the second easiest scenario; this suggests the maturity of robotics technology is beginning to match stakeholder needs. Each of the five applications were discussed in terms of the six broad enabling technology areas specified in the current National Robotics Initiative Roadmap (perception, human-robot interaction, mechanisms, modeling and simulation, control and planning, and testing and evaluation) and nine specific capabilities identified by the community as being essential to commercialization (communication, alerting, localization, fault tolerance, mapping, manpower needs, plug and play capabilities, multiple users, and multiple robots). The community believes that perception and human-robot interaction are the two biggest barriers to adoption, and require more research, given that their low technical maturity (3rd and 6th rank respectively). However, each of the specific capabilities needed for commercialization are being addressed by current research and could be achieved within 10 years with sustained funding. 

  • 15.
    Gannholm, Lovisa
    Linköping University, Department of Computer and Information Science. Linköping University, The Institute of Technology.
    A Comparative Evaluation Between Two Design Solutions for an Information Dashboard2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This study is a software usability design case about information presentation in a software dash­board. The dashboard is supposed to present system information about an enterprise resource planning system. The study aims to evaluate if the intended users of the dash­board prefer a list-based or an object-based presentation of the information and why. It also investigates if the possi­bility to get familiar with the prototype affects the evaluation’s result.

    The study was performed using parallel prototypes and evaluation with users. The use of parallel prototypes is a rather unexplored area. Likewise, little research has been done in the area of how user experience changes over time.

    Two prototypes were created, presenting the same information in two different design solutions, one list-based, and one object-based. The prototypes were evaluated with ten presumptive users, with respect to usability. The evaluation consisted of two parts, one quantitative and one qualita­tive. Half of the respondents got a chance to get familiar with the list-based prototype, and half the object-based prototype, after which they evaluated both sequentially.

    The result of the evaluation showed that seven out of ten respondents preferred the list-based prototype. The two primary reasons were that they are more used to the list-based concept from their work, and that the list-based prototype presented all information about an application at once. In the object-based prototype the user had to make a request for each type of information, which opened up in a new pop-up window.

    The primary reason that three of the ten respondents preferred the object-based prototype was that it had a more modern look, and gave a cleaner impression since it only presented the information the respondent was interested in at each point in time.

    The result also implied that the possibility to get familiar with the prototype by testing it for a couple of days affected the result. Eight out of ten respondents preferred the prototype they got familiar to, and the only ones that liked or preferred the object-based prototype were those who had gotten familiar with it.  

    The results of the study support the results of the existing research done by Dow et al. (2010) on the use of parallel prototypes, i.e. creating several prototypes in parallel, and conform with the results of the research of Karapanos et al. (2009) on how user experience changes over time.

    Some other interesting information that emerged from the study was that all but one of the respondents thought that the prototype they got familiar with had an acceptable level of usability.

    The study also validated that all respondents are positive to use a dashboard in their work, and that the presented information was enough for a first version of the dashboard. It also validated that the different groups of users would use the dashboard differently, and therefore are in need of slightly different information.

  • 16.
    Hildebrand, Cisilia
    et al.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Hörtin, Stina
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    A comparative study between Emme and Visum with respect to public transport assignment2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

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

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

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

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

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

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

  • 17.
    Lagerqvist, Victor
    Linköping University, Department of Computer and Information Science, TCSLAB - Theoretical Computer Science Laboratory.
    A comparison of SL- and unit-resolution search rules for stratified logic programs2010Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    There are two symmetrical resolution rules applicable to logic programs - SL-resolution which yields a top-down refutation and unit-resolution which yields a bottom-up refutation. Both resolution principles need to be coupled with a search rule before they can be used in practice. The search rule determines in which order program clauses are used in the refutation and affects both performance, completeness and quality of solutions. The thesis surveys exhaustive and heuristic search rules for SL-resolution and transformation techniques for (general) logic programs that makes unit-resolution goal oriented.

    The search rules were implemented as meta-interpreters for Prolog and were benchmarked on a suite of programs incorporating both deterministic and nondeterministic code. Whenever deemed applicable benchmark programs were permuted with respect to clause and goal ordering to see if it affected the interpreters performance and termination.

    With the help of the evaluation the conclusion was that alternative search rules for SL-resolution should not be used for performance gains but can in some cases greatly improve the quality of solutions, e.g. in planning or other applications where the quality of an answer correlates with the length of the refutation. It was also established that A* is more flexible than exhaustive search rules since its behavior can be fine-tuned with weighting, and can in some cases be more efficient than both iterative deepening and breadth-first search. The bottom-up interpreter based on unit-resolution and magic transformation had several advantages over the top-down interpreters. Notably for programs where subgoals are recomputed many times. The great disparity in implementation techniques made direct performance comparisons hard however, and it is not clear if even an optimized bottom-up interpreter is competitive against a top-down interpreter with tabling of answers.

  • 18.
    Bäckström, Christer
    et al.
    Linköping University, Department of Computer and Information Science, Software and Systems. Linköping University, Faculty of Science & Engineering.
    Jonsson, Peter
    Linköping University, Department of Computer and Information Science, Software and Systems. Linköping University, Faculty of Science & Engineering.
    Ordyniak, Sebastian
    Masaryk University, Czech Republic.
    Szeider, Stefan
    Vienna University of Technology, Austria.
    A complete parameterized complexity analysis of bounded planning2015In: Journal of computer and system sciences (Print), ISSN 0022-0000, E-ISSN 1090-2724, Vol. 81, no 7, 1311-1332 p.Article in journal (Refereed)
    Abstract [en]

    The propositional planning problem is a notoriously difficult computational problem, which remains hard even under strong syntactical and structural restrictions. Given its difficulty it becomes natural to study planning in the context of parameterized complexity. In this paper we continue the work initiated by Downey, Fellows and Stege on the parameterized complexity of planning with respect to the parameter "length of the solution plan." We provide a complete classification of the parameterized complexity of the planning problem under two of the most prominent syntactical restrictions, i.e., the so called PUBS restrictions introduced by Backstrom and Nebel and restrictions on the number of preconditions and effects as introduced by Bylander. We also determine which of the considered fixed-parameter tractable problems admit a polynomial kernel and which do not. (C) 2015 Elsevier Inc. All rights reserved.

  • 19.
    Peng, Huatao
    et al.
    Wuhan University of Technology, Peoples R China.
    Liu, Yang
    Linköping University, Department of Management and Engineering, Environmental Technology and Management. Hubei University of Technology, Peoples R China; University of Vaasa, Finland.
    A comprehensive analysis of cleaner production policies in China2016In: Journal of Cleaner Production, ISSN 0959-6526, E-ISSN 1879-1786, Vol. 135, 1138-1149 p.Article in journal (Refereed)
    Abstract [en]

    Studies of cleaner production have often focused on two domains: the applications and the effects. An ever-increasing importance of cleaner production is pushing researchers to pay more attention to the formulation and principles of cleaner production policies. However, there is nearly none of the previous research that systematically and comprehensively analyses the development processes of cleaner production policies and exploring their characteristics deeply. The missing study is important in not only contributing to the perfection of cleaner production policies but also influencing the strategic planning of firms. This paper bridges this gap by first presenting a comprehensive study of the development process of cleaner production policies and then exploring their characteristics. We choose China, the biggest developing country and one of the most challenging countries to implement cleaner production, as the main research target and in addition a number of other developed and developing countries for comparisons. To investigate deeper into the characteristics of cleaner production in China, all the major policies and regulations issued by central ministries from 1997 to 2013 have been studied, ensuring the accuracy and reliability of the research. By employing T-LAB software with linguistic and statistical content analysis method, this paper derives following conclusions. (1) "audit", "implementation" and "environmental" have the highest correlation coefficients with cleaner production; (2) cleaner production policies focus on four themes: "pilot", "indicator", "people" and "list"; (3) the formulation and implementation of cleaner production policies are endowed with typical characteristics of collaboration; (4) the characteristics of cleaner production policies are typically constraining types that evidently guide and regulate the behaviours of firms. This paper contributes as a general important reference of cleaner production policies for governments and firms especially in developing countries. (C) 2016 Elsevier Ltd. All rights reserved.

    The full text will be freely available from 2018-07-01 11:04
  • 20.
    Andersson, Per Gösta
    Linköping University, The Institute of Technology. Linköping University, Department of Mathematics, Mathematical Statistics .
    A conditional perspective of weighted variance estimation of the optimal regression estimator2006In: Journal of Statistical Planning and Inference, ISSN 0378-3758, Vol. 136, no 1, 221-234 p.Article in journal (Refereed)
    Abstract [en]

    The estimation of the variance for the GREG (general regression) estimator by weighted residuals is widely accepted as a method which yields estimators with good conditional properties. Since the optimal (regression) estimator shares the properties of GREG estimators which are used in the construction of weighted variance estimators, we introduce the weighting procedure also for estimating the variance of the optimal estimator. This method of variance estimation was originally presented in a seemingly ad hoc manner, and we shall discuss it from a conditional point of view and also look at an alternative way of utilizing the weights. Examples that stress conditional behaviour of estimators are then given for elementary sampling designs such as simple random sampling, stratified simple random sampling and Poisson sampling, where for the latter design we have conducted a small simulation study. © 2004 Elsevier B.V. All rights reserved.

  • 21.
    Blikstad, Mathias
    et al.
    Saab AB, Sweden.
    Karlsson, Emil
    Linköping University, Department of Mathematics, Optimization . Linköping University, Faculty of Science & Engineering.
    Lööw, Tomas
    Saab AB, Sweden.
    Rönnberg, Elina
    Linköping University, Department of Mathematics, Optimization . Linköping University, Faculty of Science & Engineering.
    A constraint generation procedure for pre-runtime scheduling of integrated modular avionic systems2017In: Proceedings of the 13th Workshop on Models and Algorithms for Planning and Scheduling Problems / [ed] Susanne Albers, Nicole Megow, Andreas S. Schulz, Leen Stougie, 2017Conference paper (Other academic)
    Abstract [en]

    In modern integrated modular avionic systems, applications share hardware resources on a common avionic platform. Such an architecture necessitates strict requirements on the spatial and temporal partitioning of the system to prevent fault propagation between different aircraft functions. One way to establish a temporal partitioning is through pre-runtime scheduling of the system, which involves creating a schedule for both tasks and a communication network.

    While the avionic systems are growing more and more complex, so is the challenge of scheduling them. Scheduling of the system has an important role in the development of new avionic systems since functionality typically is added to the system over a period of several years and a scheduling tool is used both to detect if the platform can host the new functionality and, in case this is possible, to create a new schedule. For this reason an exact solution strategy for avionics scheduling is preferred over a heuristic one.

    In this paper we present a mathematical model for an industrially relevant avionic system and present a constraint generation  procedure for scheduling of such systems. We apply our optimisation approach to instances provided by our industrial partner. These instances are of relevance for the development of future avionic systems and contain up to 20 000 tasks to be scheduled. The computational results show that our optimisation approach can be used to create schedules for such instances within reasonable time.

  • 22.
    Wiréhn, Ann-Britt
    Linköping University, Department of Medicine and Health Sciences, Health and Society. Linköping University, Faculty of Health Sciences.
    A Data-Rich World: Population‐based registers in healthcare research2007Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Advances and integration of information and communication technologies into healthcare systems offer new opportunities to improve public health worldwide. In Sweden, there are already unique possibilities for epidemiological research from registers because of a long tradition of centralized data collection into population-based registers and their allowance for linkage. The growing efficiency of automated digital storage provides growing volumes of archived data that increases the potential of analyses further.

    The purpose of this thesis can be divided into two parallel themes: illustrations and discussions of the use and usefulness of population-based registers on the one hand, and specific research questions in epidemiology and healthcare research on the other. The research questions are addressed in separate papers.

    From the Swedish Cancer Registry, 25 years of incidence data on testicular cancer was extracted for a large cohort. Record linkage to survey data on serum cholesterol showed a highly significant positive association, suggesting that elevated serum cholesterol concentration is a risk factor for testicular cancer. Since the finding is the first of its kind and because of wide confidence intervals further studies are needed to confirm the association.

    Östergötland County council’s administra-tive database (the Care Data Warehouse in Östergötland (CDWÖ)) provided data for preva-lence estimations of four common chronic diseases.

    The prevalence rate agreed very well with previous estimates for diabetes and fairly well with those for asthma. For hypertension and chronic obstructive pulmonary disease, the observed rates were lower than previous prevalence estimates. Data on several consecutive years covering all healthcare levels are needed to achieve valid prevalence estimates.

    CDWÖ data was also used to analyse the impact of diabetes on the prevalence of ischemic heart disease. Women had higher diabetes/non-diabetes prevalence rate ratios across all ages. The relative gender difference remained up to the age of 65 years and thereafter decreased considerably.

    The age-specific direct healthcare cost of diabetes was explored using data from the CDWÖ, the county council’s Cost Per Patient database and the Swedish Prescribed Drug Register. The cost per patient and the relative magnitude of different cost components varied considerably by age, which is important to consider in the future planning of diabetes management.

    The Cancer Registry was established mainly as a basis for epidemiological surveillance and research, exemplified in this thesis by a study on testicular cancer. In contrast, the newly established and planned healthcare databases in different Swedish counties are mainly for managerial purposes. As is shown in this thesis, these new databases may also be used to address problems in epidemiology and healthcare research.

    List of papers
    1. Serum cholesterol and testicular cancer incidence in 45 000 men followed for 25 years
    Open this publication in new window or tab >>Serum cholesterol and testicular cancer incidence in 45 000 men followed for 25 years
    2005 (English)In: British Journal of Cancer, ISSN 0007-0920, Vol. 92, no 9, 1785-1786 p.Article in journal (Refereed) Published
    Abstract [en]

    In a 25-year follow-up study of 44 864 men with measured serum cholesterol levels, the testicular cancer hazard ratios for the serum cholesterol categories 5.7–6.9 and ≥7.0 mmol l-1 vs the reference category (<5.7 mmol l-1) were 1.3 and 4.5, respectively; P-value for trend=0.005. This highly significant association suggests that high-serum cholesterol is a risk factor for testicular cancer.

    Keyword
    epidemiology, testicular neoplasm, cholesterol
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-12757 (URN)10.1038/sj.bjc.6602539 (DOI)
    Available from: 2007-11-06 Created: 2007-11-06 Last updated: 2011-02-03
    2. Estimating disease prevalence using a population-based administrative healthcare database
    Open this publication in new window or tab >>Estimating disease prevalence using a population-based administrative healthcare database
    2007 (English)In: Scandinavian Journal of Public Health, ISSN 1403-4948, Vol. 35, no 4, 424-431 p.Article in journal (Refereed) Published
    Abstract [en]

    Aims: In Östergötland County, Sweden, all data on hospital care and primary healthcare (PHC) have been entered in a diagnosis-related administrative database since 1999. This database was used to estimate the prevalence of four chronic diseases and to examine the capture of data in PHC, outpatient hospital care, and inpatient hospital care, considered in different time frames.

    Methods: A case-finding algorithm identified patients with at least one healthcare contact involving a diagnosis of diabetes, hypertension, asthma, or chronic obstructive pulmonary disease (COPD) in 1999—2003. Prevalence rates were calculated as the ratio of the number of identified patients alive to the total number of inhabitants on 31 December 2003 (n~415,000).

    Results: Prevalence rates were 4.4% for diabetes, 10.3% for hypertension, 4.5% for asthma, and 1.2% for COPD. For all four diagnoses, the proportions of patients identified on only one healthcare level were greatest for PHC, reaching rates of 23%, 68%, 53%, and 48%, respectively. The cases identified solely in PHC comprised larger proportions of women and patients over the age of 65 years. Considering the proportion of patients identified in 2003 in relation to the total five-year period gave values of 71%, 50%, 38%, and 58%, respectively, for the four diagnoses.

    Conclusions: The administrative healthcare databases in Sweden today can be important tools in epidemiological research. However, data on several consecutive years and both PHC and hospital data are needed to achieve valid prevalence estimates.

    Keyword
    Asthma, COPD, diabetes mellitus, epidemiology, healthcare, hypertension, inpatients, prevalence, primary outpatients, registries
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-12758 (URN)10.1080/14034940701195230 (DOI)
    Available from: 2007-11-06 Created: 2007-11-06 Last updated: 2009-05-19
    3. Age and Gender Differences in the Impact of Diabetes on the Prevalence of Ischemic Heart Disease: a Population-Based Register Study
    Open this publication in new window or tab >>Age and Gender Differences in the Impact of Diabetes on the Prevalence of Ischemic Heart Disease: a Population-Based Register Study
    2008 (English)In: Diabetes Research and Clinical Practice, ISSN 0168-8227, E-ISSN 1872-8227, Vol. 79, no 3, 497-502 p.Article in journal (Refereed) Published
    Abstract [en]

    Objective: To explore age and gender differences in the impact of diabetes on the prevalence of ischemic heart disease (IHD) in a defined population.

    Methods: Data were obtained from an administrative health care register covering a population of about 415 000. The study included all patients aged 45-74 years diagnosed between 1999-2003 with IHD (n=11 311) and diabetes (n=10 364) by physicians at all primary health care centres (PHCs) and out- and inpatient clinics at all hospitals in the county of Östergötland, Sweden.

    Results: In the 45-54 year-old age group, diabetes was associated with an increase in IHD prevalence equivalent to ageing about 20 years in women and 10 years in men. The diabetes/nondiabetes IHD prevalence rate ratio (IPR) decreased with age in both men and women (trend p-values < 0.001). The IPR was higher among women than men in each age group, though the female relative excess decreased from 75% higher in the 45-54 year-old age group to 33% higher in the 65-74 year-old age group (trend p-value = 0.018).

    Conclusions: The relative gender difference in the impact of diabetes on IHD in younger middle-aged patients remained up to the age of 65 years, decreasing considerably thereafter.

    Place, publisher, year, edition, pages
    Institutionen för medicin och hälsa, 2008
    Keyword
    aging, coronary disease, diabetes mellitus, prevalence, sex differences
    National Category
    Social Sciences
    Identifiers
    urn:nbn:se:liu:diva-11241 (URN)10.1016/j.diabres.2007.10.009 (DOI)
    Note
    Original publication: Ann-Britt E. Wiréhn, Carl Johan Östgren and John M. Carstensen, Age and Gender Differences in the Impact of Diabetes on the Prevalence of Ischemic Heart Disease: a Population-Based Register Study, 2008, Diabetes Research and Clinical Practice, (79), 3, 497-502. http://dx.doi.org/10.1016/j.diabres.2007.10.009. Copyright: Elsevier B.V., http://www.elsevier.com/Available from: 2008-03-12 Created: 2008-03-12 Last updated: 2011-02-03
    4. Age-specific direct health care costs attributable to diabetesin a Swedish population: a register-based analysis
    Open this publication in new window or tab >>Age-specific direct health care costs attributable to diabetesin a Swedish population: a register-based analysis
    2008 (English)In: Diabetic Medicine, ISSN 0742-3071, Vol. 25, no 6, 732-737 p.Article in journal (Refereed) Published
    Abstract [en]

    Aims: The aim of this population-based study was to explore the age-specific additional direct healthcare cost for patients with diabetes compared with the non-diabetic population.

    Methods: In 1999-2005, patients with diabetes in the Swedish county of Östergötland (n = 20 876) were identified from an administrative database. Cost data on the healthcare expenditure in primary healthcare, out-patient hospital care and in-patient care for the entire county population (n = ∼415 000) in 2005 were extracted from a cost per patient (CPP) database, which includes information on all utilized healthcare resources in the county. Data on drug sales were obtained from the Swedish Prescribed Drug Register.

    Results: The cost per person was 1.8 times higher in patients with diabetes than in the non-diabetic population, 7.7 times higher in children and 1.3 times higher in subjects aged > 75 years. The additional cost per person for diabetes was €1971; €3930 and €1367, respectively, for children and subjects aged > 75 years. The proportion of total additional diabetes costs attributable to in-patient care increased with age from 25 to 50%; in-patient care was the most expensive component at all ages except in children, for whom visiting a specialist was most expensive. The diabetes-related segment of the total healthcare cost was 6.6%, increasing from 2.0% in children to 10.3% in the age group 65-74 years, declining to 6.2% in the oldest age group.

    Conclusions: The direct medical cost of diabetes varies considerably by age. Knowledge about the influence of age on healthcare costs to society will be important in future planning of diabetes management.

    Keyword
    Diabetes, Economics, Healthcare delivery, Prevalence, Registers
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-12760 (URN)10.1111/j.1464-5491.2008.02444.x (DOI)
    Available from: 2007-11-06 Created: 2007-11-06 Last updated: 2009-08-21
  • 23.
    Karlsson, Anna-Carin
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Fallahsharoudi, Amir
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Johnsen, Hanna
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Hagenblad, Jenny
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Wright, Dominic
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Andersson, Leif
    Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden.
    Jensen, Per
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    A domestication related mutation in the thyroid stimulating hormonereceptor gene (TSHR) modulates photoperiodic response andreproduction in chickens2016In: General and Comparative Endocrinology, ISSN 0016-6480, E-ISSN 1095-6840, Vol. 228, 69-78 p.Article in journal (Refereed)
    Abstract [en]

    The thyroid stimulating hormone receptor gene (TSHR) has been suggested to be a ‘‘domestication locus”in the chicken. A strong selective sweep over TSHR in domestic breeds together with significant effects ofa mutation in the gene on several domestication related traits, indicate that the gene has been importantfor chicken domestication. TSHR plays a key role in the signal transduction of seasonal reproduction,which is characteristically less strict in domestic animals. We used birds from an advanced intercross linebetween ancestral Red Junglefowl (RJF) and domesticated White Leghorn (WL) to investigate effects ofthe mutation on reproductive traits as well as on TSHB, TSHR, DIO2 and DIO3 gene expression duringaltered day length (photoperiod). We bred chickens homozygous for either the mutation (d/d) or wildtype allele (w/w), allowing assessment of the effect of genotype at this locus while also controlling forbackground variation in the rest of the genome. TSHR gene expression in brain was significantly lowerin both d/d females and males and d/d females showed a faster onset of egg laying at sexual maturity thanw/w. Furthermore, d/d males showed a reduced testicular size response to decreased day length, andlower levels of TSHB and DIO3 expression. Additionally, purebred White Leghorn females kept under naturalshort day length in Sweden during December had active ovaries and lower levels of TSHR and DIO3expression compared to Red Junglefowl females kept under similar conditions. Our study indicates thatthe TSHR mutation affects photoperiodic response in chicken by reducing dependence of seasonal reproduction,a typical domestication feature, and may therefore have been important for chickendomestication.

  • 24.
    Hutter, Jonas
    et al.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Mashayeke, Mehnaz
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    A dynamic decision model and a system logic evaluation for Sandvik Machining Solutions distribution flows2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The aim of this thesis is partly to create a dynamic decision model for Sandvik Machining Solutions distribution flows and partly to evaluate how the stock transfer system logic handle four specific exceptional situations. The purpose is to reduce the total costs while keeping or improving the service level. The thesis presents a total cost model and guidelines for the planning function when deciding the main supplier in the distribution. The thesis also presents a system logic evaluation of the stock transfer logic used by Sandvik Machining Solutions.

  • 25.
    Ockander, Marlene
    Linköping University, Department of Department of Health and Society, Division of Preventive and Social Medicine and Public Health Science. Linköping University, Faculty of Health Sciences.
    A female lay perspective on health, disease, and sickness absence2001Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Background: Knowledge about a female perspective on health and disease is important to understand what happens in e.g. the medical meeting. A deeper understanding for the phenomenon of health also has social and economic importance. In Sweden women account for about 60% of the long-term cases of sickness absence.

    Aim: To explore and describe women's perceptions of health and disease and their accounts of sickness absence.

    Methods: The chronic diseases mentioned by elderly women in an interview study are compared with those documented in their respective medical records (n=199). The prevalence of positive diagnoses, overall agreement, and the kappa-coefficient were calculated for each group of diagnoses. Semi-stmctnred interviews were conducted with 82 women who had been on sick leave (60 days or more) or who had disability pension. Sixty of these middle-aged women also carried out a Q-sort.

    Results: The lowest overall agreement between the elderly women report during interviews and their medical records was observed for psychiatric diseases, followed by diseases of the gastrointestinal system. Poor chance-adjusted agreement was found concerning diseases of the gastrointestinal system and diseases of the skin (Paper I). Long-term sickness absence can be said to arise in three distinguishable "spaces": the workspace, the medical-legal space, and the mental space. In the beginning, the women were positive about sick leave as such, which they saw as an opportunity for physical rest. But as time went on, they came to regard sick leave as creating a vicious circle of new problems related to inactivity and isolation. Apart from this vicious circle and chronic physical impairments, certain conditions at the workplace, at the hospital, and the social insurance office transformed seemingly trivial sick leaves into long-term and irreversible sickness absences (Paper II). The women's accounts of being sickness absent contained interpretations of what had happened to them, how things were for the moment, and what they thought the future would bring. Three different accounts could be distinguished: the crisis, the breakpoint, and the migration. The perceptions of their own situation and especially what they thought about their future were associated with their feelings of power to initiative and well-being. The descriptions of life on sick leave are connected to a theory of "loss of work" (Paper III). For these women, to be able to get back to work was found to be equivalent to breaking away from the prospect of isolation and loneliness. Five actors were identified along with suggestions for their actions: the woman who is on sick leave herself, the employer, the health care provider, the social insurance official, and the shop-steward. It was found important to take oneself seriously and also to be taken seriously by others. The results are related to a theory of enduring and suffering (Paper IV). Six accounts representing different conceptions of health, illness, and medicine were identified and described (Paper V).

    Conclusions: The results point to the importance of doing research from different perspectives, using different methods and different sources of information to obtain a deeper understanding of a complex phenomenon like health. Above all, the results presented in this thesis point to a large variation at the individual level in perceptions, which implies the need for care in, for example, the planning of rehabilitation programs. The results also highlight the point that sick leave without follow-up from work, health care, and the social insurance office might have negative consequences on health. Implications for practice are suggested along with proposals for future research.

    List of papers
    1. Patient-doctor Concordance in Elderly Women’s Self-reported Health and Medical Records
    Open this publication in new window or tab >>Patient-doctor Concordance in Elderly Women’s Self-reported Health and Medical Records
    2002 (English)In: Methods of Information in Medicine, ISSN 0026-1270, Vol. 41, no 2, 119-124 p.Article in journal (Refereed) Published
    Abstract [en]

    OBJECTIVES: To compare the chronic diseases mentioned by elderly women in an interview study with those documented in their respective medical records.

    METHODS: The prevalence of positive diagnoses, overall agreement, and the kappa-coefficient were calculated for each group of diagnoses.

    RESULTS: The lowest overall agreement was observed for psychiatric diseases, followed by diseases of the gastrointestinal system. Poor chance-adjusted agreement was found concerning diseases of the gastrointestinal system and diseases of the skin.

    CONCLUSIONS: The results suggest that a main reason for discordance was that the elderly women feared "losing face" by reporting some diseases.

    Keyword
    diagnosis, women, medical records, patients, medical decision making
    National Category
    Social Sciences
    Identifiers
    urn:nbn:se:liu:diva-26291 (URN)12061118 (PubMedID)10807 (Local ID)10807 (Archive number)10807 (OAI)
    Available from: 2009-10-08 Created: 2009-10-08 Last updated: 2013-09-05Bibliographically approved
    2. A female lay perspective on the establishment of long-term sickness absence
    Open this publication in new window or tab >>A female lay perspective on the establishment of long-term sickness absence
    2001 (English)In: International Journal of Social Welfare, ISSN 1369-6866, E-ISSN 1468-2397, Vol. 10, no 1, 74-79 p.Article in journal (Refereed) Published
    Abstract [en]

    In Sweden women account for about 60% of the long-term cases of sickness absence. The aim of this study was to describe women's explanations as to how long-term sickness absence arises and becomes permanent, with reference to their personal experience. Semi-structured interviews were performed with 82 middle-aged women who have personal experience of long-term sickness absence. Long-term sickness absence can be said to arise in three distinguishable “spaces”: the work space, the medico-legal space and the mental space. In the beginning, the women were positive about sick-leave as such, which they saw as an opportunity for physical rest. But as time went on, they came to regard sick-leave as creating a vicious circle of new problems related to inactivity and isolation. Apart from this vicious circle and chronic physical impairments, certain conditions at the workplace, at the hospital and the social insurance office transformed seemingly trivial sick-leaves into long-term and irreversible sickness absences

    Keyword
    sickness absence, lay explanation models, women, phenomenology, interview
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-26067 (URN)10.1111/1468-2397.00154 (DOI)10526 (Local ID)10526 (Archive number)10526 (OAI)
    Available from: 2009-10-08 Created: 2009-10-08 Last updated: 2013-09-05Bibliographically approved
    3. Women's experiences of long term sickness absence: Is there a "loss of work syndrome"?
    Open this publication in new window or tab >>Women's experiences of long term sickness absence: Is there a "loss of work syndrome"?
    (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    Background: In most European countries, long-term sickness absence contribute the greatest number of days that are reimbursed due to sickness absence. This group is growing and it is constituted mainly of women.

    Aim: The present study seeks further knowledge about what happens then and there, i.e., how long-term sickness absent women handle and explain, for themselves and others, this interruption in their daily life.

    Methods: Semi-structured interviews were performed with 82 middle-aged women with personal experience from long-term sickness absence.

    Results: The women's accounts of being sickness absent contained interpretations of what had happen to them, how things were for the moment, and what they thought the future would bring. Three different accounts could be distinguished: the crisis, the breakpoint, and the migration. The perception of their own situation and especially what they thought about their future was associated with their feeling of power to initiative and well-being.

    Conclusion: From our study we have found implications for central topics of importance: time elapse, sense of coherence, reorientation/adaptation, and vital goals.

    Keyword
    Vital goal, life plan, sense of coherence, phenomenology, women, sickness absence
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-80264 (URN)
    Available from: 2012-08-23 Created: 2012-08-23 Last updated: 2013-09-05Bibliographically approved
    4. How to avoid the frightening scenario of long-term sickness absence: The advice from women with personal experience
    Open this publication in new window or tab >>How to avoid the frightening scenario of long-term sickness absence: The advice from women with personal experience
    (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    Aims: The aim of this study was to describe women's perceptions of what can be done to avoid long-term sickness absence.

    Methods: Interviews were conducted with 82 women who had been on sickness absence ( 60 days or more) or had disability pensions.

    Results: For these women, to be able to get back to work was found to be equivalent to breaking away from the prospect of isolation and loneliness. Five actors were identified along with suggestions for their actions: the woman who is on sick leave herself, the employer, the healthcare provider, the social insurance official, and the shop-steward.

    Conclusions: It is important to take oneself seriously and also to be taken seriously by others. Thus, it is important to not wait too long to take action which concerns both the individual herself and all those who get involved in her case at work, at hospital or at the social insurance office. Practical advice to reach recovery and avoid sickness absence is presented.

    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-80265 (URN)
    Available from: 2012-08-23 Created: 2012-08-23 Last updated: 2013-09-05Bibliographically approved
    5. Accounts of health, illness and medicine in women on long-term sickness absence
    Open this publication in new window or tab >>Accounts of health, illness and medicine in women on long-term sickness absence
    (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    Long-term sickness absence has grown to an important social and economic question and it affects women more than men. The specific aim of the study was to identify patterns of association between ideas of health endorsed by groups of women having a close firsthand experience of long-term sickness absence. Using the Q-methodology, in a group of 60 middle-aged women, six accounts representing different conceptions of health, illness, and medicine were identified. Future studies should be implemented to investigate the prospective value of the categorisation identified in this study e.g. to see whether, and in that case how, these conceptions affect sick leave and rehabilitation.

    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-80266 (URN)
    Available from: 2012-08-23 Created: 2012-08-23 Last updated: 2013-09-05Bibliographically approved
  • 26.
    Wang, Qunzhi
    et al.
    Department of Industrial Engineering and Management Tokyo Institute of Technology.
    Tang, Ou
    Linköping University, The Institute of Technology. Linköping University, Department of Production Economics.
    Tsao, De-bi
    Department of Industrial Engineering and Management Tokyo Institute of Technology.
    A flexible contract strategy in a supply chain with an inflexible production mode2006In: International Journal of Operational Research, ISSN 1745-7645, Vol. 1, no 3, 228-248 p.Article in journal (Refereed)
    Abstract [en]

    This paper presents a flexible supply contract with call options model for an inflexible supply chain, where the supplier only has an opportunity to produce one batch due to a long lead-time limitation. In such systems, there are eventually two decision points. At the beginning of the planning horizon, the supplier offers a wholesale price, and possibly also option purchasing and exercising prices. In addition to a firm initial order, the buyer can purchase options to adjust order quantity later. The supplier then determines the production volume. At the second decision point, with updated forecast, the buyer finalises the order quantity by exercising options. We formulate both the buyer's and the supplier's profit functions. Furthermore, we develop explicit expressions to determine the buyer's optimal decisions, and calculate the supplier's optimal decisions numerically. In numerical study, we illustrate that such a flexible contract strategy improves both the buyer's and supplier's profits. Copyright © 2006 Inderscience Enterprises Ltd.

  • 27.
    Häll, Carl Henrik
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
    A Framework for Evaluation and Design of an Integrated Public Transport System2006Licentiate thesis, monograph (Other academic)
    Abstract [en]

    Operators of public transport always try to make their service as attractive as possible, to as many persons as possible and in a so cost effective way as possible. One way to make the service more attractive, especially to elderly and disabled, is to offer door-to-door transportation. The cost for the local authorities to provide this service is very high and increases every year.

    To better serve the needs of the population and to reduce the cost for transportation of elderly and disabled, public transportation systems are evolving towards more flexible solutions. One such flexible solution is a demand responsive service integrated with a fixed route service, together giving a form of flexible public transport system. The demand responsive service can in such a system be used to carry passengers from their origin to a transfer location to the fixed route network, and/or from the fixed route network to their destination.

    This thesis concerns the development of a framework for evaluation and design of such an integrated public transport service. The framework includes a geographic information system, optimization tools and simulation tools. This framework describes how these tools can be used in combination to aid the operators in the planning process of an integrated service. The thesis also presents simulations made in order to find guidelines of how an integrated service should be designed. The guidelines are intended to help operators of public transport to implement integrated services and are found by evaluating the effects on availability, travel time, cost and other service indicators for variations in the design and structure of the service.

    In a planning system for an integrated public transport service, individual journeys must in some way be scheduled. For this reason the thesis also presents an exact optimization model of how journeys should be scheduled in this kind of service.

  • 28.
    Windridge, David
    et al.
    University of Surrey, Guildford, U.K..
    Felsberg, Michael
    Linköping University, Department of Electrical Engineering, Computer Vision. Linköping University, The Institute of Technology.
    Shaukat, Affan
    University of Surrey, Guildford, U.K..
    A Framework for Hierarchical Perception–Action Learning Utilizing Fuzzy Reasoning2013In: IEEE transactions on systems, man and cybernetics. Part B. Cybernetics, ISSN 1083-4419, E-ISSN 1941-0492, Vol. 43, no 1, 155-169 p.Article in journal (Refereed)
    Abstract [en]

    Perception-action (P-A) learning is an approach to cognitive system building that seeks to reduce the complexity associated with conventional environment-representation/action-planning approaches. Instead, actions are directly mapped onto the perceptual transitions that they bring about, eliminating the need for intermediate representation and significantly reducing training requirements. We here set out a very general learning framework for cognitive systems in which online learning of the P-A mapping may be conducted within a symbolic processing context, so that complex contextual reasoning can influence the P-A mapping. In utilizing a variational calculus approach to define a suitable objective function, the P-A mapping can be treated as an online learning problem via gradient descent using partial derivatives. Our central theoretical result is to demonstrate top-down modulation of low-level perceptual confidences via the Jacobian of the higher levels of a subsumptive P-A hierarchy. Thus, the separation of the Jacobian as a multiplying factor between levels within the objective function naturally enables the integration of abstract symbolic manipulation in the form of fuzzy deductive logic into the P-A mapping learning. We experimentally demonstrate that the resulting framework achieves significantly better accuracy than using P-A learning without top-down modulation. We also demonstrate that it permits novel forms of context-dependent multilevel P-A mapping, applying the mechanism in the context of an intelligent driver assistance system.

  • 29.
    Klein, Richard
    et al.
    Linköping University, The Tema Institute, Department of Water and Environmental Studies. Linköping University, The Tema Institute, Centre for Climate Science and Policy Research . Linköping University, Faculty of Arts and Sciences. Stockholm Environment Institute, Sweden.
    Juhola, Sirkku
    University of Helsinki, Finland; Aalto University, Finland .
    A framework for Nordic actor-oriented climate adaptation research2014In: Environmental Science and Policy, ISSN 1462-9011, E-ISSN 1873-6416, Vol. 40, 101-115 p.Article in journal (Refereed)
    Abstract [en]

    The past ten years have seen a substantial increase in research on climate change adaptation, but a large gap remains between adaptation research and action. Adaptation researchers have either failed to demonstrate the relevance of their findings to practitioners and policymakers, or stakeholders have based their views and decisions on other kinds of information. In addition, in sectors such as agriculture, forestry, nature conservation, urban planning, water management and energy supply, adaptation has been studied separately from mitigation, which contradicts the reality of many practitioners. This paper identifies five bottlenecks to the use of adaptation research in adaptation practice and policy. These bottlenecks have gone unnoticed because the traditional framing of adaptation does not adequately consider the notion of agency, often rendering stakeholder interactions ineffective. Knowledge and use of actor-oriented theory when analysing and discussing adaptation needs and options could serve to find ways to overcome the bottlenecks and narrow the gap between research and action. The paper presents a novel framework for actor-oriented adaptation research that is being conducted within the Nordic Centre of Excellence for Strategic Adaptation Research (NORD-STAR). It frames climate adaptation as addressing both the impacts of climate change and the consequences of climate policy. Two methodological approaches - modelling and visualisation, and policy analysis - are applied to three thematic issues: land-use change, energy transitions, and insurance and finance.

  • 30.
    Wzorek, Mariusz
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Computer and Information Science, KPLAB - Knowledge Processing Lab.
    Doherty, Patrick
    Linköping University, The Institute of Technology. Linköping University, Department of Computer and Information Science, KPLAB - Knowledge Processing Lab.
    A framework for reconfigurable path planning for autonomous unmanned aerial vehicles.2007Manuscript (preprint) (Other (popular science, discussion, etc.))
  • 31.
    Wzorek, Mariusz
    et al.
    Linköping University, Department of Computer and Information Science, Artificial Intelligence and Integrated Computer Systems. Linköping University, Faculty of Science & Engineering.
    Berger, Cyrille
    Linköping University, Department of Computer and Information Science, Artificial Intelligence and Integrated Computer Systems. Linköping University, Faculty of Science & Engineering.
    Doherty, Patrick
    Linköping University, Department of Computer and Information Science, Artificial Intelligence and Integrated Computer Systems. Linköping University, Faculty of Science & Engineering.
    A Framework for Safe Navigation of Unmanned Aerial Vehicles in Unknown Environments2017In: 25th International Conference on Systems Engineering, 2017Conference paper (Refereed)
    Abstract [en]

    This paper presents a software framework which combines reactive collision avoidance control approach with path planning techniques for the purpose of safe navigation of multiple Unmanned Aerial Vehicles (UAVs) operating in unknown environments. The system proposed leverages advantages of using a fast local sense-and-react type control which guarantees real-time execution with computationally demanding path planning algorithms which generate globally optimal plans. A number of probabilistic path planning algorithms based on Probabilistic Roadmaps and Rapidly- Exploring Random Trees have been integrated. Additionally, the system uses a reactive controller based on Optimal Reciprocal Collision Avoidance (ORCA) for path execution and fast sense-and-avoid behavior. During the mission execution a 3D map representation of the environment is build incrementally and used for path planning. A prototype implementation on a small scale quad-rotor platform has been developed. The UAV used in the experiments was equipped with a structured-light depth sensor to obtain information about the environment in form of occupancy grid map. The system has been tested in a number of simulated missions as well as in real flights and the results of the evaluations are presented. 

  • 32.
    Noroozi, Sayeh
    Linköping University, Department of Management and Engineering, Production Economics. Linköping University, The Institute of Technology.
    A Framework for Sales and Operations Planning in Process Industries2014Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    This thesis studies Sales and Operations Planning (S&OP) in process industries. S&OP is a planning process which has a role of balancing demand and supply at an aggregate level. S&OP has traditionally been considered as a generic process meaning that it is independent from the context of the industry in which it is implemented. Process industries do; however, have specific characteristics which affect their planning and control processes, including S&OP. Therefore, the aim in this thesis is to reconcile these two contradictory stances and furthermore investigate how the specific properties in process industries should be included into an S&OP framework. Such a differentiated framework aims to support process industries to design/implement their S&OP process based on their unique requirements in relation to their markets, products and processes while it also takes into account the specific characteristics regarding the continuous production. Consequently, the process industries would realize the expected benefits from S&OP process to a greater extent.

    The study starts with a literature review on S&OP in process industries in order to build the knowledge foundation for subsequent studies. The results show that the underlying difference between process industries and discrete industries is the object continuity which affects the selection of production processes including resources. Thus, process industries are often hybrids in the sense that their production processes include both continuous production, when the transformed object (material) is continuous, and discrete production when the object (material) turns into discrete products after the discretization point. In other words, process industries deploy both continuous production and discrete production while discrete industries use only discrete production. The specific characteristics of process industries are actually related to the continuous production part and influence the planning processes as well. As the result of this study, the continuous production characteristics that can affect the S&OP process are identified.

    In the continuation of the thesis and in order to provide a typology for planning and control purposes, the object type (continuous and discrete) is combined with two other dimensions i.e. mode type (onetime, intermittent and continuous) and driver type (customer order driven and forecast driven) into a planning and control typology. The mode type addresses the repetitivity of the flow and the driver type takes into account the trigger of the flow. Each dimension has a transition point – i.e. the discretization point for the object type, mode interface point for the mode type and customer order decoupling point for the driver type – and represents a hybrid situation since different production environments are required before and after each transition point. The typology aims to illustrate how each dimension affects the planning and control issues as well as how the dimensions are interrelated and how this combination influence the managerial decisions. The typology integrates the concepts from both process industries and discrete industries and thus, is applicable for both.

    Thereafter the typology is applied to the S&OP process and an integrated framework is suggested based on the three dimensions with specific focus on process industries. In this framework, the effects of hybridities within each dimension and cross-hybridities between the dimensions on the S&OP process are also considered. The importance of hybridities and cross-hybridities lies in the fact that the planning of the hybrid systems is a complex task due to the varying managerial decisions before and after the transition points. Finally, implementation steps for the suggested S&OP framework are outlined for the process industries in order to position themselves in the framework, identify the implementing procedures, and obtain potential benefits based on the differentiated S&OP process.

    List of papers
    1. Sales and operations planning in the process industry: A literature review
    Open this publication in new window or tab >>Sales and operations planning in the process industry: A literature review
    2017 (English)In: International Journal of Production Economics, ISSN 0925-5273, E-ISSN 1873-7579, Vol. 188, 139-155 p.Article in journal (Refereed) Published
    Abstract [en]

    This paper provides a systematic literature review of Sales and Operations Planning (S&OP) in process industries. The aim is to investigate the present state of S&OP in process industries in comparison to discrete manufacturing industries and to identify the desired future state of the S&OP process based on the specific characteristics of process industries. The findings of this paper show that this issue has not received much attention in the academic world. Hence there is a need for conceptual models with focus on process industries’ specific characteristics. Process industries are actually hybrids of continuous production and discrete production (respectively, upstream and downstream of the discretization point) and the specific characteristics of process industries are related to the continuous production part. Thus, in this paper, the characteristics upstream of the discretization point are investigated and the integration of them in the S&OP process of the process industries is stressed.

    Place, publisher, year, edition, pages
    Elsevier, 2017
    Keyword
    Sales and operations planning, Process industry, Discretization point
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-106705 (URN)10.1016/j.ijpe.2017.03.006 (DOI)000401381300013 ()
    Note

    The original title in manuskript fiorm of this article was Sales and operations planning in the process industry.

    Funding agencies: Swedish Foundation for Strategic Research (SSF)

    Available from: 2014-05-19 Created: 2014-05-19 Last updated: 2017-06-13Bibliographically approved
    2. A modularised typology for flow design based on decoupling points - a holistic view on process industries and discrete manufacturing industries
    Open this publication in new window or tab >>A modularised typology for flow design based on decoupling points - a holistic view on process industries and discrete manufacturing industries
    2016 (English)In: Production planning & control (Print), ISSN 0953-7287, E-ISSN 1366-5871, Vol. 27, no 16, 1344-1355 p.Article in journal (Refereed) Published
    Abstract [en]

    Management of production activities covers a wide range of decisions. In this paper, a modularised approach is suggested that, through configuration, generates a case-specific flow design. The approach is based on identification of decision categories that are generic and fundamental in the flow design, covering both discrete manufacturing industries and process industries. Each decision category identifies a unique property of the flow which changes at a particular point: this is termed a decoupling point. A three-dimensional modularised typology is developed by combining three different decision categories. Cases from the steel industry and the tooling industry are used to illustrate how the typology can be applied. The modularised approach provides a typology for the application of both qualitative and quantitative methods for flow management, including planning, control and performance management.

    Place, publisher, year, edition, pages
    TAYLOR & FRANCIS LTD, 2016
    Keyword
    Typology; decoupling point; planning and control; process industry; modularisation
    National Category
    Production Engineering, Human Work Science and Ergonomics
    Identifiers
    urn:nbn:se:liu:diva-132245 (URN)10.1080/09537287.2016.1220649 (DOI)000384468200004 ()
    Note

    Funding Agencies|Swedish Foundation for Strategic Research [PIC-LI]; Process Industrial IT and Automation (PiiA) - VINNOVA; Swedish Energy Agency, Formas; Swedish industry [2014-05110]

    Available from: 2016-10-24 Created: 2016-10-21 Last updated: 2017-04-11
    3. A modularized framework for sales and operations planning with focus on process industries
    Open this publication in new window or tab >>A modularized framework for sales and operations planning with focus on process industries
    2016 (English)In: Production & Manufacturing Research, ISSN 2169-3277, Vol. 4, no 1, 65-89 p.Article in journal (Refereed) Published
    Abstract [en]

    This paper suggests a modularized sales and operations planning (S&OP) framework, consisting of content and process. The framework’s content is based on a typology of decoupling points in which the effect of decoupling points on the decision variables in S&OP is studied. The framework’s process takes a step back and addresses the need for a more elaborate design to precede the operational use of S&OP content for different production contexts. The framework supports both process industries (PIs) and discrete manufacturing industries (DIs), and recognizes their specific requirements and reflects them in their S&OP. The differentiating characteristics of PIs and DIs are emphasized through three different decoupling points, namely: discretization decoupling point, control mode decoupling point, and customer order decoupling point. The suggested framework aims to fill the gap in the literature regarding the lack of aggregate planning processes that match the PIs’ specific requirements by reflecting the differentiating characteristics of PIs in S&OP.

    Place, publisher, year, edition, pages
    Taylor & Francis, 2016
    National Category
    Economics and Business Other Mechanical Engineering Software Engineering
    Identifiers
    urn:nbn:se:liu:diva-133240 (URN)10.1080/21693277.2016.1200502 (DOI)
    Available from: 2016-12-15 Created: 2016-12-15 Last updated: 2017-04-11Bibliographically approved
  • 33.
    Ballester, Facundo
    et al.
    University of Valencia, Spain.
    Carlsson Tedgren, Åsa
    Linköping University, Department of Medical and Health Sciences, Division of Radiological Sciences. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Surgery, Orthopaedics and Cancer Treatment, Department of Radiation Physics. Karolinska University Hospital, Sweden.
    Granero, Domingo
    Hospital Gen University, Spain.
    Haworth, Annette
    Peter MacCallum Cancer Centre, Australia; RMIT University, Australia.
    Mourtada, Firas
    Helen F Graham Cancer Centre, DE 19713 USA.
    Paiva Fonseca, Gabriel
    CNEN SP, Brazil; Maastricht University, Netherlands.
    Zourari, Kyveli
    University of Athens, Greece.
    Papagiannis, Panagiotis
    University of Athens, Greece.
    Rivard, Mark J.
    Tufts University, MA 02111 USA.
    Siebert, Frank-Andre
    University Hospital Schleswig Holstein, Germany.
    Sloboda, Ron S.
    Cross Cancer Institute, Canada; University of Alberta, Canada.
    Smith, Ryan L.
    Alfred Hospital, Australia.
    Thomson, Rowan M.
    Carleton University, Canada.
    Verhaegen, Frank
    Maastricht University, Netherlands; McGill University, Canada.
    Vijande, Javier
    University of Valencia, Spain; IFIC CSIC UV, Spain.
    Ma, Yunzhi
    CHU Quebec, Canada; University of Laval, Canada; University of Laval, Canada.
    Beaulieu, Luc
    CHU Quebec, Canada; University of Laval, Canada; University of Laval, Canada.
    A generic high-dose rate Ir-192 brachytherapy source for evaluation of model-based dose calculations beyond the TG-43 formalism2015In: Medical physics (Lancaster), ISSN 0094-2405, Vol. 42, no 6, 3048-3062 p.Article in journal (Refereed)
    Abstract [en]

    Purpose: In order to facilitate a smooth transition for brachytherapy dose calculations from the American Association of Physicists in Medicine (AAPM) Task Group No. 43 (TG-43) formalism to model-based dose calculation algorithms (MBDCAs), treatment planning systems (TPSs) using a MBDCA require a set of well-defined test case plans characterized by Monte Carlo (MC) methods. This also permits direct dose comparison to TG-43 reference data. Such test case plans should be made available for use in the software commissioning process performed by clinical end users. To this end, a hypothetical, generic high-dose rate (HDR) Ir-192 source and a virtual water phantom were designed, which can be imported into a TPS. Methods: A hypothetical, generic HDR Ir-192 source was designed based on commercially available sources as well as a virtual, cubic water phantom that can be imported into any TPS in DICOM format. The dose distribution of the generic Ir-192 source when placed at the center of the cubic phantom, and away from the center under altered scatter conditions, was evaluated using two commercial MBDCAs [Oncentra (R) Brachy with advanced collapsed-cone engine (ACE) and BrachyVision AcuRos (TM)]. Dose comparisons were performed using state-of-the-art MC codes for radiation transport, including ALGEBRA, BrachyDose, GEANT4, MCNP5, MCNP6, and pENELopE2008. The methodologies adhered to recommendations in the AAPM TG-229 report on high-energy brachytherapy source dosimetry. TG-43 dosimetry parameters, an along-away dose-rate table, and primary and scatter separated (PSS) data were obtained. The virtual water phantom of (201)(3) voxels (1 mm sides) was used to evaluate the calculated dose distributions. Two test case plans involving a single position of the generic HDR Ir-192 source in this phantom were prepared: (i) source centered in the phantom and (ii) source displaced 7 cm laterally from the center. Datasets were independently produced by different investigators. MC results were then compared against dose calculated using TG-43 and MBDCA methods. Results: TG-43 and PSS datasets were generated for the generic source, the PSS data for use with the ACE algorithm. The dose-rate constant values obtained from seven MC simulations, performed independently using different codes, were in excellent agreement, yielding an average of 1.1109 +/- 0.0004 cGy/(h U) (k = 1, Type A uncertainty). MC calculated dose-rate distributions for the two plans were also found to be in excellent agreement, with differences within type A uncertainties. Differences between commercial MBDCA and MC results were test, position, and calculation parameter dependent. On average, however, these differences were within 1% for ACUROS and 2% for ACE at clinically relevant distances. Conclusions: A hypothetical, generic HDR Ir-192 source was designed and implemented in two commercially available TPSs employing different MBDCAs. Reference dose distributions for this source were benchmarked and used for the evaluation of MBDCA calculations employing a virtual, cubic water phantom in the form of a CT DICOM image series. The implementation of a generic source of identical design in all TPSs using MBDCAs is an important step toward supporting univocal commissioning procedures and direct comparisons between TPSs. (C) 2015 American Association of Physicists in Medicine.

  • 34.
    Steins, Krisjanis
    et al.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Walther, Sten
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Thoracic and Vascular Surgery. Linköping University, Faculty of Health Sciences.
    A generic simulation model for planning critical care resource requirements2013In: Anaesthesia, ISSN 0003-2409, E-ISSN 1365-2044, Vol. 68, no 11, 1148-1155 p.Article in journal (Refereed)
    Abstract [en]

    Intensive care capacity planning based on factual or forecasted mean admission numbers and mean length of stay without taking non-linearity and variability into account is fraught with error. Simulation modelling may allow for a more accurate assessment of capacity needs. We developed a generic intensive care simulation model using data generated from anonymised patient records of all admissions to four different hospital intensive care units. The model was modified and calibrated stepwise to identify important parameters and their values to obtain a match between model predictions and actual data. The most important characteristic of the final model was the dependency of admission rate on actual occupancy. Occupancy, coverage and transfers of the final model were found to be within 2% of the actual data for all four simulated intensive care units. We have shown that this model could provide accurate decision support for planning critical care resource requirements.

  • 35.
    Norin, Anna
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Science and Technology.
    Andersson, Tobias
    Linköping University, The Institute of Technology. Linköping University, Department of Science and Technology.
    Värbrand, Peter
    Linköping University, The Institute of Technology. Linköping University, Department of Science and Technology.
    Yuan, Di
    Linköping University, The Institute of Technology. Linköping University, Department of Science and Technology, Communications and Transport Systems.
    A GRASP Heuristic for Scheduling De-icing trucks at Stockholm Arlanda Airport2007In: 6th Eurocontrol Innovative Research Workshop and Exhibition,2007, 2007Conference paper (Other academic)
    Abstract [en]

    It is a fact that the most delays in the Air Transportation System (ATS) today occur at the airport. One reason for this is the large number of actors operating at the airport and the scarcity of communication between them and other parts of the ATS. Airport Logistics is a concept developed to survey all the flows of ehicles, people, material and information, which can be found on and around the airport. The objective is to increase efficiency, where one part is to decrease the delays. As an initial step, the turn-around process is analysed and an optimization model for the planning of de-icing trucks is implemented. The model shows that large savings can be made both by reducing the travelling distances for the trucks and reducing the delays the de-icing process is causing the ATS. However, most important is the advantage of having a plan for how the de-icing trucks should be utilized, something that is missing today.  

  • 36.
    Olofsson, Ida
    et al.
    ReachIn Technologies, Sweden.
    Lundin, Karljohan
    Linköping University, Department of Science and Technology, Visual Information Technology and Applications (VITA). Linköping University, The Institute of Technology.
    Cooper, Matthew
    Linköping University, Department of Science and Technology, Visual Information Technology and Applications (VITA). Linköping University, The Institute of Technology.
    Kjäll, Per
    Elekta AB, Sweden.
    Ynnerman, Anders
    Linköping University, Department of Science and Technology, Visual Information Technology and Applications (VITA). Linköping University, The Institute of Technology.
    A haptic interface for dose planning in stereo-tactic radio-surgery2004Conference paper (Refereed)
  • 37.
    Mahdavi Mazdeh, Mohammad
    et al.
    Iran University of Science and Technology, Iran.
    Emadikhiav, Mohsen
    Linköping University, Department of Management and Engineering. Linköping University, Faculty of Science & Engineering.
    Parsa, Iman
    Iran University of Science and Technology, Iran.
    A heuristic to solve the dynamic lot sizing problem with supplier selection and quantity discounts2015In: Computers & industrial engineering, ISSN 0360-8352, Vol. 85, 33-43 p.Article in journal (Refereed)
    Abstract [en]

    In the present study, the single-item dynamic lot sizing problem with supplier selection is investigated. The problem is broken down into two different cases. In the first case, quantity discounts are not taken into account; in the second case, incremental and all-unit quantity discounts are considered. Due to the complexity of the problems, a new heuristic is developed, which is based on the Fordyce-Webster Algorithm (Fordyce and Webster, 1984). In order to solve the problem where multiple suppliers are considered, a third dimension is added to the matrices used in the Fordyce-Webster Algorithm. The solutions gained using the proposed algorithm are similar to those of Parsa, Khiav, Mazdeh, and Mehrani (2013) in terms of accuracy and computational time. However, the implementation of matrices makes this method easy to explain in comparison with other heuristics developed for similar problems. (C) 2015 Elsevier Ltd. All rights reserved.

  • 38.
    Pettersson, Johanna
    et al.
    Linköping University, Department of Biomedical Engineering, Medical Informatics. Linköping University, Center for Medical Image Science and Visualization (CMIV). Linköping University, The Institute of Technology.
    Knutsson, Hans
    Linköping University, Department of Biomedical Engineering, Medical Informatics. Linköping University, Center for Medical Image Science and Visualization (CMIV). Linköping University, The Institute of Technology.
    Nordqvist, Per
    Melerit Medical AB .
    Borga, Magnus
    Linköping University, Department of Biomedical Engineering, Medical Informatics. Linköping University, Center for Medical Image Science and Visualization (CMIV). Linköping University, The Institute of Technology.
    A hip surgery simulator based on patient specific models generated by automatic segmentation2006In: Medicine Meets Virtual Reality 14: Accelerating Change in Healthcare: Next Medical Toolkit / [ed] James D Westwood; et al, Amsterdam, Nederländerna: IOS Press, 2006, 431-436 p.Conference paper (Refereed)
    Abstract [en]

    The use of surgical simulator systems for education and preoperative planning is likely to increase in the future. A natural course of development of these systems is to incorporate patient specific anatomical models. This step requires some kind of segmentation process in which the different anatomical parts are extracted. Anatomical datasets are, however, usually very large and manual processing would be too demanding. Hence, automatic, or semi-automatic, methods to handle this step are required. The framework presented in this paper uses nonrigid registration, based on the morphon method, to automatically segment the hip anatomy and generate models for a hip surgery simulator system.

  • 39.
    Holm, Åsa
    et al.
    Linköping University, Department of Mathematics, Optimization . Linköping University, The Institute of Technology.
    Larsson, Torbjörn
    Linköping University, Department of Mathematics, Optimization . Linköping University, The Institute of Technology.
    Carlsson Tedgren, Åsa
    Linköping University, Department of Medical and Health Sciences, Division of Radiological Sciences. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Center for Surgery, Orthopaedics and Cancer Treatment, Department of Radiation Physics.
    A linear programming model for optimizing HDR brachytherapy dose distributions with respect to mean dose in the DVH-tail2013In: Medical physics (Lancaster), ISSN 0094-2405, Vol. 40, no 8Article in journal (Refereed)
    Abstract [en]

    Purpose: Recent research has shown that the optimization model hitherto used in high-dose-rate (HDR) brachytherapy corresponds weakly to the dosimetric indices used to evaluate the quality of a dose distribution. Although alternative models that explicitly include such dosimetric indices have been presented, the inclusion of the dosimetric indices explicitly yields intractable models. The purpose of this paper is to develop a model for optimizing dosimetric indices that is easier to solve than those proposed earlier. less thanbrgreater than less thanbrgreater thanMethods: In this paper, the authors present an alternative approach for optimizing dose distributions for HDR brachytherapy where dosimetric indices are taken into account through surrogates based on the conditional value-at-risk concept. This yields a linear optimization model that is easy to solve, and has the advantage that the constraints are easy to interpret and modify to obtain satisfactory dose distributions. less thanbrgreater than less thanbrgreater thanResults: The authors show by experimental comparisons, carried out retrospectively for a set of prostate cancer patients, that their proposed model corresponds well with constraining dosimetric indices. All modifications of the parameters in the authors model yield the expected result. The dose distributions generated are also comparable to those generated by the standard model with respect to the dosimetric indices that are used for evaluating quality. less thanbrgreater than less thanbrgreater thanConclusions: The authors new model is a viable surrogate to optimizing dosimetric indices and quickly and easily yields high quality dose distributions.

  • 40.
    Strömgren, Per
    et al.
    Division of Transport planning, Economics and Engineering, Royal Institute of Technology (KTH), Stockholm, Sweden.
    Olstam, Johan
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering. Swedish National Road and Transport Research Institute (VTI), Linköping, Sweden.
    A Model for Capacity Reduction at Roadwork Zone2016In: International Symposium on Enhancing Highway Performance (ISEHP), (7th International Symposium on Highway Capacity and Quality of Service, 3rd International Symposium on Freeway and Tollway Operations), Elsevier, 2016, Vol. 15, 245-256 p.Conference paper (Refereed)
    Abstract [en]

    This paper presents an investigation of capacity reduction in connection with roadwork zones. The paper presents a state-of-the-art description on roadwork effects on capacity. Based on the literature on this topic the most important parameters that should be incorporated in a Swedish capacity manual for the operation and maintenance roadwork are: the proportion of heavy traffic; lane width; number of closed lanes; closed road shoulder; proportion of commuter traffic; and length of roadwork zone. The paper presents a comparison of a composite model of correction factors from Germany, USA and Denmark and the Dutch model for computation of capacity reduction. The comparison show that the two models essentially gives the same results. Based on these results a model was developed. The model developed was validated using empirical data from a full scale test at the motorway network in Gothenburg. The throughput was measured in two cases during the morning and afternoon peak hour. The capacity for the normal site conditions was estimated based on traffic flow and speed data from the same site. The result shows that the empirically estimated capacity reduction is consistent with the reduction calculated with the new model for the different road work designs evaluated. The conclusion is that the model developed seems to be valid for capacity reduction estimations of roadworks on Swedish motorways but that more empirics are needed to ensure general validity.

  • 41.
    Leifler, Ola
    et al.
    Linköping University, Department of Computer and Information Science, MDALAB - Human Computer Interfaces. Linköping University, The Institute of Technology.
    Eriksson, Henrik
    Linköping University, Department of Computer and Information Science, MDALAB - Human Computer Interfaces. Linköping University, The Institute of Technology.
    A Model for Document Processing in Semantic Desktop Systems2008In: Proceedings of the I-KNOW '08, the International Conference on Knowledge Management, Berlin, Heidelberg: Springer Verlag , 2008Conference paper (Refereed)
    Abstract [en]

    There is a significant gap between the services provided by dedicated information systems and general desktop systems for document communication and preparation. This situation is a serious knowledge-management problem, which often results in information loss, poor communication, and confusion among users. Semantic desktops promise to bring knowledge-based services to common desktop applications and, ultimately, to support knowledge management by adding advanced functionality to familiar computing environments. By custom tailoring these systems to different application domains, it is possible to provide dedicated services that assist users in combining document handling and communication with structured workflow processes and the services provided by dedicated systems. This paper presents a model for developing custom-tailored document processing for semantic-desktop systems. Our approach has been applied to the domain of military command and control, which as based on highly-structured document-driven processes. Key Words: semantic desktop, document-driven processes, semantic documents, planning

  • 42.
    Holm, Christer
    et al.
    Linköping University, Department of Mathematics.
    Larsson, Andreas
    Linköping University, Department of Mathematics.
    A Model for Multiperiod Route Planning and a Tabu Search Method for Daily Log Truck Scheduling2004Independent thesis Basic level (professional degree)Student thesis
    Abstract [en]

    The transportation cost of logs from forest to customers is a large part of the overall cost for the Swedish forestry industry. Finding good routes from harvesting points to saw and pulp mills is a complex task, where the total number of feasible routes is extremely high. In this thesis we present two methods for log truck scheduling.

    The first is to, from a given set of routes, find the most valuable subset that fulfils the customers demand. We use a model that is similar to the set partitioning problem and a method that is referred to as a composite pricing coupled with Branch and Bound. The composite pricing based method prices the routes (columns) and chooses the most valuable ones that are then added to the LP relaxation. Once an LP optimum is found, the Branch and Bound method is used to find an integer optimum solution. We have tested this on a case of realistic size.

    The second method is a tabu search heuristic. Here, the purpose is to create efficient and qualitative routes from a given number of trips (referred to as predefined trips). From a start solution tabu search systematically generates new solutions. This method was tested on a small problem and on a five times larger problem to study how the size of the problem affected the result. It was also tested and compared on two cases in which the backhauling possibilities (i.e. instead of traveling empty the truck picks up another load on the return trip) had and had not been studied. The composite pricing based method and the tabu search method proved to be very useful for this kind of scheduling.

  • 43.
    Malusek, Alexandr
    et al.
    Linköping University, Department of Medical and Health Sciences, Division of Radiological Sciences. Linköping University, Faculty of Medicine and Health Sciences.
    Magnusson, Maria
    Linköping University, Department of Electrical Engineering, Computer Vision. Linköping University, Faculty of Science & Engineering. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    Sandborg, Michael
    Linköping University, Department of Medical and Health Sciences, Division of Radiological Sciences. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Surgery, Orthopaedics and Cancer Treatment, Department of Radiation Physics. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    Alm Carlsson, Gudrun
    Linköping University, Department of Medical and Health Sciences, Division of Radiological Sciences. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Surgery, Orthopaedics and Cancer Treatment, Department of Radiation Physics. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    A model-based iterative reconstruction algorithm DIRA using patient-specific tissue classification via DECT for improved quantitative CT in dose planning2017In: Medical physics (Lancaster), ISSN 0094-2405, Vol. 44, no 6, 2345-2357 p.Article in journal (Refereed)
    Abstract [en]

    Purpose: To develop and evaluate-in a proof-of-concept configuration-a novel iterative reconstruction algorithm (DIRA) for quantitative determination of elemental composition of patient tissues for application to brachytherapy with low energy (amp;lt; 50 keV) photons and proton therapy. Methods: DIRA was designed as a model-based iterative reconstruction algorithm, which uses filtered backprojection, automatic segmentation and multimaterial tissue decomposition. The evaluation was done for a phantom derived from the voxelized ICRP 110 male phantom. Soft tissues were decomposed to the lipid, protein and water triplet, bones were decomposed to the compact bone and bone marrow doublet. Projections were derived using the Drasim simulation code for an axial scanning configuration resembling a typical DECT (dual-energy CT) scanner with 80 kV and Sn140 kV x-ray spectra. The iterative loop produced mono-energetic images at 50 and 88 keV without beam hardening artifacts. Different noise levels were considered: no noise, a typical noise level in diagnostic imaging and reduced noise level corresponding to tenfold higher doses. An uncertainty analysis of the results was performed using type A and B evaluations. The two approaches were compared. Results: Linear attenuation coefficients averaged over a region were obtained with relative errors less than 0.5% for all evaluated regions. Errors in average mass fractions of the three-material decomposition were less than 0.04 for no noise and reduced noise levels and less than 0.11 for the typical noise level. Mass fractions of individual pixels were strongly affected by noise, which slightly increased after the first iteration but subsequently stabilized. Estimates of uncertainties in mass fractions provided by the type B evaluation differed from the type A estimates by less than 1.5% for most cases. The algorithm was fast, the results converged after 5 iterations. The algorithmic complexity of forward polyenergetic projection calculation was much reduced by using material doublets and triplets. Conclusions: The simulations indicated that DIRA is capable of determining elemental composition of tissues, which are needed in brachytherapy with low energy (amp;lt; 50 keV) photons and proton therapy. The algorithm provided quantitative monoenergetic images with beam hardening artifacts removed. Its convergence was fast, image sharpness expressed via the modulation transfer function was maintained, and image noise did not increase with the number of iterations. c 2017 American Association of Physicists in Medicine

    The full text will be freely available from 2018-05-04 12:54
  • 44.
    Wikner, Joakim
    et al.
    Linköping University, Department of Management and Engineering, Production Economics. Linköping University, Faculty of Science & Engineering.
    Noroozi, Sayeh
    Linköping University, Department of Management and Engineering, Production Economics. Linköping University, Faculty of Science & Engineering.
    A modularised typology for flow design based on decoupling points - a holistic view on process industries and discrete manufacturing industries2016In: Production planning & control (Print), ISSN 0953-7287, E-ISSN 1366-5871, Vol. 27, no 16, 1344-1355 p.Article in journal (Refereed)
    Abstract [en]

    Management of production activities covers a wide range of decisions. In this paper, a modularised approach is suggested that, through configuration, generates a case-specific flow design. The approach is based on identification of decision categories that are generic and fundamental in the flow design, covering both discrete manufacturing industries and process industries. Each decision category identifies a unique property of the flow which changes at a particular point: this is termed a decoupling point. A three-dimensional modularised typology is developed by combining three different decision categories. Cases from the steel industry and the tooling industry are used to illustrate how the typology can be applied. The modularised approach provides a typology for the application of both qualitative and quantitative methods for flow management, including planning, control and performance management.

  • 45.
    Noroozi, Sayeh
    et al.
    Linköping University, Department of Management and Engineering, Production Economics. Linköping University, Faculty of Science & Engineering.
    Wikner, Joakim
    Linköping University, Department of Management and Engineering, Production Economics. Linköping University, Faculty of Science & Engineering.
    A modularized framework for sales and operations planning with focus on process industries2016In: Production & Manufacturing Research, ISSN 2169-3277, Vol. 4, no 1, 65-89 p.Article in journal (Refereed)
    Abstract [en]

    This paper suggests a modularized sales and operations planning (S&OP) framework, consisting of content and process. The framework’s content is based on a typology of decoupling points in which the effect of decoupling points on the decision variables in S&OP is studied. The framework’s process takes a step back and addresses the need for a more elaborate design to precede the operational use of S&OP content for different production contexts. The framework supports both process industries (PIs) and discrete manufacturing industries (DIs), and recognizes their specific requirements and reflects them in their S&OP. The differentiating characteristics of PIs and DIs are emphasized through three different decoupling points, namely: discretization decoupling point, control mode decoupling point, and customer order decoupling point. The suggested framework aims to fill the gap in the literature regarding the lack of aggregate planning processes that match the PIs’ specific requirements by reflecting the differentiating characteristics of PIs in S&OP.

  • 46.
    Westin, C.-F.
    et al.
    Surgical Planning Laboratory, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, United States, Surgical Planning Laboratory, Brigham and Women's Hospital, Harvard Medical School, 75 Francis St., Boston, MA 02115, United States.
    Wigström, Lars
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Loock, T.
    Sjoqvist, L.
    Kikinis, R.
    Surgical Planning Laboratory, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, United States.
    Knutsson, Hans
    Linköping University, The Institute of Technology. Linköping University, Department of Biomedical Engineering, Medical Informatics.
    A multielement RF coil for MRI guidance of interventional devices2001In: Journal of Magnetic Resonance Imaging, ISSN 1053-1807, Vol. 14, no 1, 56-62 p.Article in journal (Refereed)
    Abstract [en]

    Accurate localization of minimally invasive devices is critical to the success of interventional procedures. Device orientation and tip position are two of the most important pieces of information needed to define device location for magnetic resonance imaging (MRI)-guided interventional procedures. While a single one-element micro coil incorporated into an interventional device has proven to be effective in some applications, it can only supply tip position information. However, multiple positions on the device are necessary to also determine its orientation. For this purpose, a novel single micro coil design with three separate winding elements that provides both the device orientation and tip position is described in this study. Definition of MR scan planes, by using the device orientation and the target tissue location, permits automatic tracking of the insertion of the device. Furthermore, devices that include this coil design are permitted to bend to a limited extent. This makes the micro coil design appropriate for many flexible interventional devices. Reliable near-real-time tracking of three points on an interventional device is demonstrated on a 0.2T MRI system with modest gradient performance. Phantom and in vivo animal experiments are used to demonstrate the utility of this new coil design. © 2001 Wiley-Liss, Inc.

  • 47.
    Aghighi, Meysam
    et al.
    Linköping University, Department of Computer and Information Science, Software and Systems. Linköping University, Faculty of Science & Engineering.
    Bäckström, Christer
    Linköping University, Department of Computer and Information Science, Software and Systems. Linköping University, Faculty of Science & Engineering.
    A Multi-parameter Complexity Analysis of Cost-optimal and Net-benefit Planning2016Conference paper (Refereed)
    Abstract [en]

    Aghighi and Bäckström have previously studied cost-optimal planning (COP) and net-benefit planning (NBP) for three action cost domains: the positive integers (Z_+), the non-negative integers (Z_0) and the positive rationals (Q_+). These were indistinguishable under standard complexity analysis for both problems, but separated for COP using parameterised complexity analysis. With the plan cost, k, as parameter, COP was W[2]-complete for Z_+, but para-NP-hard for both Z_0 and Q_+, i.e. presumably much harder. NBP was para-NP-hard for all three domains, thus remaining unseparable. We continue by considering combinations with several additional parameters and also the non-negative rationals (Q_0). Examples of new parameters are the plan length, l, and the largest denominator of the action costs, d. Our findings include: (1) COP remains W[2]-hard for all domains, even if combining all parameters; (2) COP for Z_0 is in W[2] for the combined parameter {k,l}; (3) COP for Q_+ is in W[2] for {k,d} and (4) COP for Q_0 is in W[2] for {k,d,l}. For NBP we consider further additional parameters, where the most crucial one for reducing complexity is the sum of variable utilities. Our results help to understand the previous results, eg. the separation between Z_+ and Q_+ for COP, and to refine the previous connections with empirical findings.

  • 48.
    Jansson, Elise
    Linköping University, Department of Social and Welfare Studies.
    "A Nation On the Move": A Discourse Analysis of Namibian Policies for Development2010Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This thesis is approaching the concept of development in Namibian plans for development, its Vision 2030 and Third National Development Plan. The aim is to analyse discourses of development in the Namibian political context of planning for development. I have done this through the theoretical and methodological framework of Norman Fairclough’s critical discourse analysis, CDA. I have identified four contrasting and complementing discourses in the way that the documents talk about development. Two of them, discourse of tradition and discourse of modernity, are connected to meanings of development. The two others, a social equity and justice discourse and a neo-liberal market discourse, are connected to structures of development, which shape how the documents vision development to happen. I have seen that there is a struggle between the discourses in the way they are described as both complementing and conflicting.

  • 49.
    Naim, M.M.
    et al.
    Cardiff University, Wales .
    Wikner, Joakim
    Linköping University, Department of Management and Engineering, Production Economics. Linköping University, The Institute of Technology.
    Grubbström, Robert W.
    Linköping University, Department of Management and Engineering, Production Economics. Linköping University, The Institute of Technology.
    A net present value assessment of make-to-order and make-to-stock manufacturing systems2007In: Omega: The International Journal of Management Science, ISSN 0305-0483, E-ISSN 1873-5274, Vol. 35, no 5, 524-532 p.Article in journal (Refereed)
    Abstract [en]

    This paper shows the impact of using the net present value (NPV) on parameter selection in the ordering policy of a production planning and control system. Using a well understood and documented model, the net present value is used as an objective function to determine the discounted future variance costs resulting from the model's dynamics. The NPV of the variance (NPVv) is defined and applied to the model under make-to-order and make-to-stock conditions. We show that the cost structure of the manufacturing system defines the NPVv and hence aids in identifying the most appropriate control strategy to apply. © 2005 Elsevier Ltd. All rights reserved.

  • 50.
    Rönnqvist, Mikael
    Linköping University, The Institute of Technology. Linköping University, Department of Mathematics, Optimization .
    A new support system for tactical transportation planning2003In: 5th EUROINFORMS Joint International meeting,2003, 2003Conference paper (Other academic)
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