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  • 28701.
    Öhrwall Rönnbäck, Anna
    et al.
    Linköping University, Department of Management and Engineering, Industrial Marketing and Industrial Economics. Linköping University, The Institute of Technology.
    Risberg, Per
    Saab Combitech.
    Att leda högteknologiska innovationsföretag: Erfarenheter från Combitech 1977-19972009Book (Other (popular science, discussion, etc.))
    Abstract [sv]

    Per Risberg skapade Combitech-gruppen och var dess koncernchef i 20 år. Genom detta hade han en unik erfarenhet av att starta och driva fram tillväxt av teknikbaserade nya företag. Ur SAAB-koncernens huvudsakligen militära verksamhet, med en både bred och djup teknikbas, initierade Per nya kompetensområden och byggde upp en grupp mindre, applikationsfokuserade, självständiga men helägda bolag, som tillsammans bildade Combitech-gruppen. Gruppen utvecklades framgångsrikt under Pers ledarskap, och bidrog till ökat värdeskapande och ökad tillväxt.

    I VINNOVAs arbete är tillväxt i mindre företag ett viktigt fokus. För VINNOVA-anställda som arbetar med teknikbaserade nya företag är det mycket värdefullt att ta del av Pers erfarenheter från Combitech-tiden. Det blev därför mycket uppskattat när Per lovade att berätta om sina erfarenheter inom ramen för en serie om sju heldagsseminarier för VINNOVAs anställda.

    I denna seminarieserie, som löpte under åren 2007-2008, delade Per, på ett öppet, utförligt och

    personligt sätt, med sig av sina kunskaper och erfarenheter. Hans insikter grundar sig på upplevelser av både med- och motgång, och lockade åhörarna till både eftertänksamhet och många goda skratt.

    Pers berättelse är nu dokumenterad i denna sammanfattande skrift, förtjänstfullt nedtecknad av Tekn dr. Anna Öhrwall Rönnbäck. Berättelsen utgår från ett antal konkreta fallbeskrivningar som underbygger hans slutsatser och reflektioner, organiserade under ett antal teman.

    Vi vill hävda att Per hade en unik erfarenhet av att bygga upp ny teknikbaserad affärsverksamhet samt att han utvecklade ett spännande framgångskoncept med Combitech-gruppen. Att på detta sätt få möjlighet att ta del av och dokumentera dessa erfarenheter har stort värde. Vi känner stor och djup tacksamhet till Per för att han på ett engagerat och pedagogiskt sätt delade med sig av sina kunskaper. 

    VINNOVA hoppas och tror att du som läsare kan få inspiration och vägledning kring vilka faktorer som är avgörande för att ett teknikbaserat nytt företag skall lyckas. Det är också vår förhoppning att innehållet ska stimulera till diskussion och bidra till att ge såväl VINNOVAs medarbetare som VINNOVAs bidragsmottagare, samt övriga läsare, en ökad kännedom kring, och förståelse för frågeställningar som är väsentliga i vårt gemensamma arbete med att främja och skapa hållbar tillväxt.

  • 28702.
    Öhrwall Rönnbäck, Anna
    et al.
    Linköping University, Department of Management and Engineering, Industrial Marketing and Industrial Economics . Linköping University, The Institute of Technology.
    Rosén, Thomas
    Linköping University, Department of Management and Engineering, Industrial Marketing and Industrial Economics . Linköping University, The Institute of Technology.
    Olsson, Claes-Olof
    Föreningen Sambruk.
    Goldkuhl, Göran
    Linköping University, Department of Management and Engineering, VITS - Development of Informations Systems and Work Context. Linköping University, Faculty of Arts and Sciences.
    Innovative Business Models Enhancing Open Source Software in the Public Sector2010Conference paper (Refereed)
    Abstract [en]

    The objective of this paper is to suggest new business models and supporting arrangements for open source software in the public sector, specifically for municipalities. Methodologically, the study was carried out as a practical inquiry. Results from the initial diagnosis of longitudinal case studies 2005-2008 in a Swedish network of 80 collaborating municipalities, and a survey 2008 to all Swedish national and local authorities, indicated that Swedish municipalities do not use OSS to a large extent for several reasons, and that experience sharing and a supporting framework were requested. As a solution, a semi-open business model framework was suggested. This framework was developed and implemented in the form of action research. Evaluation of the implementation indicated two major conclusions presented in this paper. First, it that a semi-open source business model could strengthen the community, in so motto that the user-driven innovative solutions stay under control of the user organization. This prevents that the customer’s own development efforts in collaborative projects unintentionally are transferred to supplier companies, and need to be re-purchased in the form of packaged solutions, a phenomena that was observed in several previously studied cases. Second, it was concluded that the semi-open source business model can work only if both customer-side and supplier-side can take advantage. An open attitude to enhance fulfilment of the supplier’s drivers, such as commercialization opportunities, is needed from the customer side. Otherwise important knowledge contributions from suppliers may be limited.

  • 28703.
    Öhrwall Rönnbäck, Anna
    et al.
    Linköping University, Department of Management and Engineering, Industrial Marketing and Industrial Economics. Linköping University, The Institute of Technology.
    Sjöström, Roland
    Linköping University, Department of Management and Engineering, Industrial Marketing and Industrial Economics. Linköping University, The Institute of Technology.
    Uddenberg, Anders
    Linköping University, Department of Management and Engineering, Industrial Marketing and Industrial Economics. Linköping University, The Institute of Technology.
    Brege, Staffan
    Linköping University, Department of Management and Engineering, Industrial Marketing and Industrial Economics. Linköping University, The Institute of Technology.
    Evaluating innovation aspects for rapid growth in SMEs2012In: Proceedings of the XXIII ISPIM Conference: “Action for Innovation: Innovating from Experience” / [ed] Ian Bitran, ISPIM , 2012Conference paper (Other academic)
    Abstract [en]

    The importance of fast-growing companies, so-called gazelles, for

    the creation of jobs and wealth in society is undisputed (e.g. Birch 1981). Less

    is known about how a firm can become – and stay – a gazelle. While

    innovation is often pointed out as a key to successful business development, the

    relationship between investments in innovation and R&D activities and

    profitable long-term growth is still unclear. The aim of this paper is to evaluate

    the importance of innovation aspects for rapid growth in small and mediumsized

    enterprises, SMEs. Empirically, it is based on an initiative to enhance fast

    growth in SMEs in a region in Sweden. Early results from analyzing 39 cases

    indicate that innovation factors distinguish fast-growing companies from lowgrowing

    ones.

  • 28704.
    Öhrwall Rönnbäck, Anna
    et al.
    Linköping University, Department of Management and Engineering, Industrial Marketing and Industrial Economics. Linköping University, The Institute of Technology.
    Zander, Ivo
    Stockholms universitet.
    Ur startblocken: svensk innovationskraft II: baserad på Forum for Innovation Managements seminarier och salongsdebatter under 2004-2007 : bidrag från inbjudna medskribenter och intervjupersoner2008Book (Other (popular science, discussion, etc.))
    Abstract [sv]

    Ur startblocken – Svensk innovationskraft II. I den här boken ger Forum for Innovation Management, FIM, en samlad bild av Sveriges förutsättningar som innovationsland nu och i framtiden. Bokens teman speglar fims seminarier och salongsdebatter under 2004–2007 och baseras på intervjuer och texter av tongivande personer i Innovationssverige, bland andra Ayad Al Saffar, Efva Attling, Leif Johansson, Lars G Josefsson, Margareta Norell Bergendal, Maud Olofsson, Alf Rehn, Lena Treschow Torell, Per Unckel och Thomas Östros. Boken avslutas med ett manifest riktat till Sveriges beslutsfattare i innovationsfrågor. © Forum for Innovation Management (FIM) 2008. isbn: 978-91-633-2409-3.

  • 28705.
    Öhrwall Rönnbäck, Anna
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Management and Economics.
    Öhlund Sandström, Gunilla
    Developing Integrated Product and Service Offerings: A Comparison Between Large and Small Manufacturing Firms' Business2007In: 2nd National Workshop on Functional Product Development and Sales 2007,2007, Luleå: Luleå Tekniska Universitet , 2007Conference paper (Refereed)
  • 28706.
    Ölundh Sandström, Gunilla
    et al.
    KTH, Stockholm, Sweden.
    Janhager, Jenny
    KTH, Stockholm, Sweden.
    Öhrwall Rönnbäck, Anna
    Linköping University, Department of Management and Engineering, Industrial Economics. Linköping University, The Institute of Technology.
    Lindahl, Mattias
    Linköping University, Department of Management and Engineering, Environmental Technology and Management. Linköping University, The Institute of Technology.
    Sundin, Erik
    Linköping University, Department of Management and Engineering, Assembly technology. Linköping University, The Institute of Technology.
    Sakao, Tomohiko
    Linköping University, Department of Management and Engineering, Environmental Technology and Management. Linköping University, The Institute of Technology.
    Managing Innovation Processes for a Business-Driven Collaborative Network to Export Total Technical Solutions2008In: ISPIM Innovation Symposium, 2008, Singapore: ISPIM , 2008Conference paper (Other academic)
    Abstract [en]

    There is a large need of environmental solutions at developing countries, where a network of small firms, e.g. in Sweden, have much opportunity for their business. This paper discusses, from both theoretical and from practical aspects, the high degree of complexity that needs to be managed when small firms export environmental-technology innovation to emerging markets. Especially, it deals with how a network of firms should manage its innovation processes. Based on the review of some 50 literature, the paper explains the methodologies adopted in an on-going project to study these issues. Discussions include differences with development of an integration of products/services within a single firm.

  • 28707.
    Ölvander, Johan
    Linköping University, The Institute of Technology. Linköping University, Department of Management and Engineering, Machine Design.
    Design of Fluid Power Systems Using a Multi-Objective Genetic Algorithm2004In: Applications of Multi-Objective Evolutionary Algorithms / [ed] Carlos A. Coello Coello, Gary B. Lamont, Singapore: World Scientific , 2004, -761 p.Chapter in book (Other academic)
    Abstract [en]

    This book presents an extensive variety of multi-objective problems across diverse disciplines, along with statistical solutions using multi-objective evolutionary algorithms (MOEAs). The topics discussed serve to promote a wider understanding as well as the use of MOEAs, the aim being to find good solutions for high-dimensional real-world design applications. The book contains a large collection of MOEA applications from many researchers, and thus provides the practitioner with detailed algorithmic direction to achieve good results in their selected problem domain.

  • 28708.
    Ölvander, Johan
    Linköping University, The Institute of Technology. Linköping University, Department of Management and Engineering, Machine Design .
    Robustness considerations in multi-objective optimal design2005In: Journal of engineering design (Print), ISSN 0954-4828, E-ISSN 1466-1837, Vol. 16, no 5, 511-523 p.Article in journal (Refereed)
    Abstract [en]

    In real-world engineering design problems we have to search for solutions that simultaneously optimize a wide range of different criteria. Furthermore, the optimal solutions also have to be robust. Therefore, this paper presents a method where a multi-objective genetic algorithm is combined with response surface methods in order to assess the robustness of the identified optimal solutions. The design example is two different concepts of hydraulic actuation systems, which have been modelled in a simulation environment to which an optimization algorithm has been coupled. The outcome from the optimization is a set of Pareto optimal solutions that elucidate the trade-off between energy consumption and control error for each system. Based on these Pareto fronts, promising regions could be identified for each concept. In these regions, sensitivity analyses are performed and thus it can be determined how different design parameters affect the system at different optimal solutions.

  • 28709.
    Ölvander, Johan
    Linköping University, The Institute of Technology. Linköping University, Department of Management and Engineering, Machine Design.
    Sensitivity Analysis in Multi-objective Evolutionary Design, in Recent Advances in Simulated Evolution and Learning2004In: Recent Advances in Simulated Evolution and Learning / [ed] K. C. Tan, Singapore: World Scientific series on Advances in Natural Computation , 2004, 2, -832 p.Chapter in book (Other academic)
    Abstract [en]

          Inspired by the Darwinian framework of evolution through natural selection and adaptation, the field of evolutionary computation has been growing very rapidly, and is today involved in many diverse application areas. This book covers the latest advances in the theories, algorithms, and applications of simulated evolution and learning techniques. It provides insights into different evolutionary computation techniques and their applications in domains such as scheduling, control and power, robotics, signal processing, and bioinformatics. The book will be of significant value to all postgraduates, research scientists and practitioners dealing with evolutionary computation or complex real-world problems

  • 28710.
    Ölvander, Johan
    et al.
    Linköping University, Department of Management and Engineering, Machine Design. Linköping University, The Institute of Technology.
    Feng, X.
    ABB Corporate Research, Västerås, Sweden.
    Holmgren, B.
    ABB Corporate Research, Västerås, Sweden.
    Optimal kinematics design of an industrial robot family in 2008 Proceedings of the ASME International Design Engineering Technical Conferences and Computers and Information in Engineering Conference, DETC 2008, vol 1, issue PART B, pp 777-7872009In: ASME 2008 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference: Volume 1: 34th Design Automation Conference, Parts A and B, The American Society of Mechanical Engineers (ASME) , 2009, Vol. 1, no PART B, 777-787 p.Conference paper (Refereed)
    Abstract [en]

    Product family design is a well recognized method to address the demands of mass customization. A potential drawback of product families is that the performance of individual members are reduced due to the constraints added by the common platform, i.e. parts and components need to be shared by other family members. This paper presents a formal mathematical framework where the product family design problem is stated as an optimization problem and where optimization is used to find an optimal product family. The object of study is kinematics design of a family of industrial robots. The robot is a serial manipulator where different robots share arms from a common platform. The objective is to show the trade-off between the size of the common platform and the kinematics performance of the robot.

  • 28711.
    Ölvander, Johan
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Management and Engineering, Machine Design .
    Krus, Petter
    Linköping University, The Institute of Technology. Linköping University, Department of Mechanical Engineering, Machine Design.
    A multi-objective optimization approach to aircraft preliminary design2004In: SAE Transactions Journal of Aerospace, 454-460 p.Article in journal (Refereed)
  • 28712.
    Ölvander, Johan
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Mechanical Engineering, Machine Design.
    Krus, Petter
    Linköping University, The Institute of Technology. Linköping University, Department of Mechanical Engineering, Machine Design.
    Optimizing the Optimization - A Method for Comparison of Optimization Algorithms2006In: AIAA Multidisciplinary Design Optimization Specialists Conference,2006, Newport, RI; USA: AIAA , 2006Conference paper (Refereed)
  • 28713.
    Ölvander, Johan
    et al.
    Linköping University, Department of Management and Engineering, Machine Design . Linköping University, The Institute of Technology.
    Lundén, Björn
    Linköping University, Department of Management and Engineering, Machine Design . Linköping University, The Institute of Technology.
    Gavel , Hampus
    Saab Aerosystems.
    A computerized optimization framework for the morphological matrix applied to aircraft conceptual design2009In: Computer-Aided Design, ISSN 0010-4485, E-ISSN 1879-2685, Vol. 41, no 3, 187-196 p.Article in journal (Refereed)
    Abstract [en]

    This paper presents a formal mathematical framework for the use of the morphological matrix in a computerized conceptual design framework. Within the presented framework, the matrix is quantified so that each solution principle is associated with a set of characteristics such as weight, cost, performance, etc. Selection of individual solutions is modeled with decision variables and an optimization problem is formulated. The applications are the conceptual design of subsystems for an Unmanned Aerial Vehicle and an aircraft fuel transfer system. Both the system models and the mathematical framework are implemented in MS Excel.

  • 28714.
    Ölvander, Johan
    et al.
    Linköping University, Department of Management and Engineering, Machine Design. Linköping University, The Institute of Technology.
    Tarkian, Mehdi
    Linköping University, Department of Management and Engineering, Machine Design. Linköping University, The Institute of Technology.
    Feng, Xiaolong
    Linköping University, Department of Management and Engineering, Machine Design. Linköping University, The Institute of Technology.
    Multi-objective Optimization of a family of Industrial Robots2011In: Multi-objective Evolutionary Optimisation for Product Design and Manufacturing / [ed] Wang L., Ng A. H.C., Deb K., Springer Verlag , 2011, 189-217 p.Chapter in book (Refereed)
    Abstract [en]

    With the increasing complexity and dynamism in today’s product design and manufacturing, more optimal, robust and practical approaches and systems are needed to support product design and manufacturing activities. Multi-objective Evolutionary Optimisation for Product Design and Manufacturing presents a focused collection of quality chapters on state-of-the-art research efforts in multi-objective evolutionary optimisation, as well as their practical applications to integrated product design and manufacturing. Multi-objective Evolutionary Optimisation for Product Design and Manufacturing consists of two major sections. The first presents a broad-based review of the key areas of research in multi-objective evolutionary optimisation. The second gives in-depth treatments of selected methodologies and systems in intelligent design and integrated manufacturing. Recent developments and innovations in multi-objective evolutionary optimisation make Multi-objective Evolutionary Optimisation for Product Design and Manufacturing a useful text for a broad readership, from academic researchers to practicing engineers.

  • 28715.
    Ölvingson, Christina
    Linköping University, Department of Computer and Information Science. Linköping University, The Institute of Technology.
    On development of information systems with GIS functionality in public health informatics: a requirements engineering approach2003Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Public health informatics has in recent years emerged as a field of its own from medical informatics. Since public health informatics is newly established and also new to public health professionals, previous research in the field is relatively scarce. Even if the overlap with medical informatics is large, there are differences between the two fields. Public health is, for example, more theoretical and more multi-professional than most clinical fields and the focus is on populations rather than individuals. These characteristics result in a complex setting for development of information systems. To our knowledge there exist few systems that support the collaborative process that constitutes the foundation of public health programs. Moreover, most applications that do support public health practitioners are small-scale, developed for a specific purpose and have not gained any wider recognition.

    The main objective of this thesis is to explore a novel approach to identifying the requirements for information system support with geographical information system (GIS) functionality in public health informatics. The work is based on four case studies that are used to provide the foundation for the development of an initial system design. In the first study, problems that public health practitioners experience in their daily work were explored. The outcome of the study was in terms of descriptions of critical activities. In the second study, the use case map notation was exploited for modeling the process of public health programs. The study provides a contextual description of the refinement of data to information that could constitute a basis for both political and practical decision in complex inter-organizational public health programs. In the third study, ethical conflicts that arose when sharing geographically referenced data in public health programs were analyzed to find out how these affect the design of information systems. The results pointed out issues that have to be considered when developing public health information systems. In the fourth study, the use of information systems with GIS functionality in WHO Safe Communities in Sweden and the need for improvements were explored. The study resulted in identification of particular needs concerning information system support among public health practitioners.

    From these studies, general knowledge about the issues public health practitioners experience in daily practice was gained and the requirements identified were used as a starting-point for the design of information systems for Motala WHO Safe Community.

    The main contributions of the thesis involve two areas: public health informatics and requirements engineering. First, a novel approach to system development in public health informatics is presented. Second, the application of use case maps as a tool for requirements engineering in complex settings such as public health programs is presented. Third, the introduction of requirements engineering in public health informatics has been exemplified. The contributions of the thesis should enhance the possibility to perform more adequate requirements engineering in the field of public health informatics. As a result, it should be possible to develop information systems that better meet the needs in the field of public health. Hence, it contributes to making the public health programs more effective, which in the long run will improve public health. 

  • 28716.
    Ölvingson, Christina
    et al.
    Linköping University, Department of Computer and Information Science. Linköping University, The Institute of Technology.
    Hallberg, Jonas
    Linköping University, Department of Computer and Information Science. Linköping University, The Institute of Technology.
    Timpka, Toomas
    Linköping University, Department of Computer and Information Science. Linköping University, Department of Department of Health and Society. Linköping University, The Institute of Technology.
    Lindqvist, Kent
    Linköping University, Department of Computer and Information Science. Linköping University, Department of Department of Health and Society. Linköping University, The Institute of Technology.
    Ethical issues in public health informatics: implications for system design when sharing geographic information2002In: Journal of Biomedical Informatics, ISSN 1532-0464, E-ISSN 1532-0480, Vol. 35, no 3, 178-185 p.Article in journal (Refereed)
    Abstract [en]

    Public health programs today constitute a multi-professional inter-organizational environment, where both health service and other organizations are involved. Developing information systems, including the IT security measures needed to suit this complex context, is a challenge. To ensure that all involved organizations work together towards a common goal, i.e., promotion of health, an intuitive strategy would be to share information freely in these programs. However, in practice it is seldom possible to realize this ideal scenario. One reason may be that ethical issues are often ignored in the system development process. This investigation uses case study methods to explore ethical obstacles originating in the shared use of geographic health information in public health programs and how this affects the design of information systems. Concerns involving confidentiality caused by geographically referenced health information and influences of professional and organizational codes are discussed. The experience presented shows that disregard of ethical issues can result in a prolonged development process for public health information systems. Finally, a theoretical model of design issues based on the case study results is presented.

  • 28717.
    Ölvingson, Christina
    et al.
    Linköping University, Department of Computer and Information Science. Linköping University, The Institute of Technology.
    Hallberg, Niklas
    Linköping University, Department of Computer and Information Science. Linköping University, The Institute of Technology.
    Timpka, Toomas
    Linköping University, Department of Computer and Information Science. Linköping University, Department of Department of Health and Society. Linköping University, The Institute of Technology.
    Design of information systems for Public Health Programs: the case of Motala WHO safe communityManuscript (preprint) (Other academic)
    Abstract [en]

    Objectives: In public health only a fraction of the potential that information systems (ISs) and geographical information systems (GISs) provides has been used. Public-health programs are executed in complex environments, and are characterized by being multi-professional and inter-organizational. Hence, there is a need for extensive studies of how ISs should be con figured to truly support public health practitioners. The objective of this study is to explore how information technology, including GIS functionality, should be configured to support practitioners in community-based public health programs.

    Measurements: The critical incident technique, interviews, the voice of the customer table, and use case maps were used for data collection.

    Results: Communication and a clearinghouse with contact persons were identified as key features and support for creating both official and unofficial contact networks is provided. The design has a module-based architecture, including an extendable easy-to-use module with GIS functionality.

    Conclusions: To support both individuals and heterogonous teams in complex public health programs, a module-based architecture is proposed. Hence, the system can be tailor-made to support individuals in their specific tasks and at their specific skill level.

  • 28718.
    Ölvingson, Christina
    et al.
    Linköping University, Department of Computer and Information Science. Linköping University, The Institute of Technology.
    Hallberg, Niklas
    Linköping University, Department of Computer and Information Science. Linköping University, The Institute of Technology.
    Timpka, Toomas
    Linköping University, Department of Computer and Information Science. Linköping University, Department of Department of Health and Society. Linköping University, The Institute of Technology.
    Prerequisites to use information system as support in Public Health Programs: an initial requirements elicitation and analysis for WHO safe sommunitiesManuscript (preprint) (Other academic)
    Abstract [en]

    The public health context constitutes a heterogeneous environment and presents a complex task for system developers. In this study, the requirements elicitation and analysis of prerequisites for using information systems (ISs) in public health programs is investigated. Special interest is also paid to geographical information system (GIS) functionality. The specific objective of this study is to explore the need for support of ISs and GISs that exists in WHO Safe Communities in Sweden. To elicit the requirements, a questionnaire based on the critical incident technique (CIT) was used. By using CIT, it is possible to focus the development on the problems experienced by the users. Moreover, it covers both technical and social requirements. Thereafter a voice of the customer table is used to transform the needs to technical requirements. The study results in recommendations for ISs development with GIS functionality for public health practitioners.

  • 28719.
    Ölvingson, Christina
    et al.
    Linköping University, Department of Computer and Information Science. Linköping University, The Institute of Technology.
    Hallberg, Niklas
    Linköping University, Department of Computer and Information Science. Linköping University, The Institute of Technology.
    Timpka, Toomas
    Linköping University, Department of Department of Health and Society. Linköping University, Faculty of Health Sciences.
    Greenes, RA
    Adaptation of the critical incident technique to requirements engineering in public health2001In: Studies in Health Technology and Informatics, ISSN 0926-9630, E-ISSN 1879-8365, Vol. 84, no 2, 1180-1184 p.Article in journal (Refereed)
    Abstract [en]

    The introduction of modern information systems in public health provides new possibilities for improvements in public health services and hence also of population's health. However, development of information systems that truly supports public health practices requires that technical, cognitive, and social issues be taken into consideration. In requirements engineering for public health, a notable problem is that of capturing all aspects of the future user's voices, i.e., the viewpoints of different public health practitioners. Failing to capture these voices will result in inefficient or even useless systems. The aim of this paper is to report a requirements-engineering instrument to describe problems in the daily work of public health professionals. The issues of concern thus captured can be used as the basis for formulating the requirements of information systems for public health professionals.

  • 28720.
    Ölvingson, Christina
    et al.
    Linköping University, Department of Computer and Information Science. Linköping University, The Institute of Technology.
    Hallberg, Niklas
    Linköping University, Department of Computer and Information Science. Linköping University, Department of Department of Health and Society. Linköping University, The Institute of Technology.
    Timpka, Toomas
    Linköping University, Department of Computer and Information Science. Linköping University, Department of Department of Health and Society. Linköping University, The Institute of Technology.
    Greenes, Robert A.
    Decision Systems Group, Harvard Medical School and Brigham and Women's Hospital, Boston, MA, USA.
    Using the critical incident technique to define a minimal data set for requirements elicitation in public health2002In: International Journal of Medical Informatics, ISSN 1386-5056, E-ISSN 1872-8243, Vol. 68, no 1-3, 165-174 p.Article in journal (Refereed)
    Abstract [en]

    The introduction of computer-based information systems (ISs) in public health provides enhanced possibilities for service improvements and hence also for improvement of the population's health. Not least, new communication systems can help in the socialization and integration process needed between the different professions and geographical regions. Therefore, development of ISs that truly support public health practices require that technical, cognitive, and social issues be taken into consideration. A notable problem is to capture ‘voices’ of all potential users, i.e., the viewpoints of different public health practitioners. Failing to capture these voices will result in inefficient or even useless systems. The aim of this study is to develop a minimal data set for capturing users' voices on problems experienced by public health professionals in their daily work and opinions about how these problems can be solved. The issues of concern thus captured can be used both as the basis for formulating the requirements of ISs for public health professionals and to create an understanding of the use context. Further, the data can help in directing the design to the features most important for the users.

  • 28721.
    Ölvingson, Christina
    et al.
    Linköping University, Department of Computer and Information Science, EISLAB - Economic Information Systems. Linköping University, The Institute of Technology.
    Hallberg, Niklas
    Linköping University, Department of Computer and Information Science, MDALAB - Human Computer Interfaces. Linköping University, The Institute of Technology.
    Timpka, Toomas
    Linköping University, Department of Medicine and Health Sciences, Division of Preventive and Social Medicine and Public Health Science. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre for Public Health Sciences.
    Lindqvist, Kent
    Linköping University, Department of Medicine and Health Sciences, Division of Preventive and Social Medicine and Public Health Science. Linköping University, Faculty of Health Sciences.
    Ethical issues in public health projects: Implications of geographic information resolution2002In: Alvarez I:, Ward Bynum T., Àlvaro de Assis Lopes J., and Rogerson S. Proceedings of the sixth international conference: The transformation of organisations in the information Age: Social and ethical implications. ETHICOMP 2002, 2002Conference paper (Refereed)
  • 28722.
    Ölvingson, Christina
    et al.
    Linköping University, Department of Computer and Information Science. Linköping University, The Institute of Technology.
    Hallberg, Niklas
    Linköping University, Department of Computer and Information Science. Linköping University, The Institute of Technology.
    Timpka, Toomas
    Linköping University, Department of Computer and Information Science. Linköping University, Department of Department of Health and Society. Linköping University, The Institute of Technology.
    Lindqvist, Kent
    Linköping University, Department of Computer and Information Science. Linköping University, Department of Department of Health and Society. Linköping University, The Institute of Technology.
    Requirements Engineering for inter-organizational health information systems with functions for spatial analyses: modeling a WHO safe community applying Use Case Maps2002In: Methods of Information in Medicine, ISSN 0026-1270, Vol. 41, no 4, 299-304 p.Article in journal (Refereed)
    Abstract [en]

    Objectives: To evaluate Use Case Maps (UCMs) as a technique for Requirements Engineering (RE) in the development of information systems with functions for spatial analyses in inter-organizational public health settings.

    Methods: In this study, Participatory Action Research (PAR) is used to explore the UCM notation for requirements elicitation and to gather the opinions of the users. The Delphi technique is used to reach consensus in the construction of UCMs.

    Results: The results show that UCMs can provide a visualization of the system's functionality and in combination with PAR provide a sound basis for gathering requirements in inter-organizational settings. UCMs were found to represent a suitable level for describing the organization and the dynamic flux of information including spatial resolution to all stakeholders. Moreover, by using PAR, the voices of the users and their tacit knowledge is intercepted. Further, UCMs are found useful in generating intuitive requirements by the creation of use cases.

    Conclusions: With UCMs and PAR it is possible to study the effects of design changes in the general information display and the spatial resolution in the same context. Both requirements on the information system in general and the functions for spatial analyses are possible to elicit when identifying the different responsibilities and the demands on spatial resolution associated to the actions of each administrative unit. However, the development process of UCM is not well documented and needs further investigation and formulation of guidelines.

  • 28723.
    Öman, Michael
    Linköping University, Department of Management and Engineering, Solid Mechanics. Linköping University, The Institute of Technology.
    Optimization and Robustness of Structural Product Families2011Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    This thesis concerns structural optimization and robustness evaluations, and new methods are presented that considerably reduce the computational cost of these evaluations.

    Optimization is an effective tool in the design process and the interest from industry of its usage is quickly increasing. However, the usage would probably have grown faster if the required number of computationally costly finite element analyses could be reduced. Especially in the case of product family optimization, the problem size can easily get too large to be solved within a reasonable time. This is sometimes also true for robustness evaluations. To enable the usage of optimization and robustness evaluations also for large scale industrial problems, two new methods are here presented, which require a considerably smaller number of finite element analyses.

    The first method concerns structural optimization of product families subjected to multiple crash load cases. Here, the number of required finite element analyses are considerably reduced by only considering the critical constraint in each iteration step.

    The second method is an approach to approximate the variable sensibility based on the distribution of internal energy in a structure. The method can be used to evaluate the relative robustness of different design proposals or for structural optimization. Since the method is independent of the number of parameters and design variables the computational cost of such evaluations is drastically reduced for computationally large problems.

  • 28724.
    Öman, Michael
    Linköping University, Department of Management and Engineering, Solid Mechanics. Linköping University, The Institute of Technology.
    Optimization and robustness of structural product families2009Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    This thesis concerns structural optimization of product families and robustness. The overall objective is to find a method for performing structural optimization of product families subjected to multiple crash load cases and to ensure a robust behavior.

    A product family is a family of products where every product variant, or family member, shares at least one component with at least one other product in the family. Structural optimization of such a family is complex and for expensive function evaluations, e.g. crash simulations, the computing time to solve the problem with traditional methods gets unrealistically long. Therefore, a new optimization algorithm for product families is presented, called the critical constraint method (CCM), that reduces the number of required evaluations by only considering the active constraints in the optimal solution.

    Traditionally optimized structures have a tendency of being sensitive to small variations in the design or loading conditions. As these kind of variations are inevitable, it is important to account for this sensitivity in the design process to ensure the robustness of the optimized design.

    The thesis is divided in two parts. The first part serves as a theoretical background to the second part, the two appended articles. This first part includes introductions to the concepts of product families, optimization, meta modeling and robust design.

    The first appended paper presents a new optimization algorithm for product families subjected to multiple crash loads. The method is compared to traditional methods and tested on two smaller product family examples.

    The second paper is an application of an existing sensitivity analysis method on a large industrial application example. A sensitivity analysis is performed on a Scania truck cab subjected to an impact load in order to identify the most  influencing variables on the crash responses.

  • 28725.
    Öman, Michael
    et al.
    Linköping University, Department of Management and Engineering, Solid Mechanics. Linköping University, The Institute of Technology.
    Asadi Rad, Nima
    Linköping University, Department of Management and Engineering, Solid Mechanics. Linköping University, The Institute of Technology.
    Nilsson, Larsgunnar
    Linköping University, Department of Management and Engineering, Solid Mechanics. Linköping University, The Institute of Technology.
    Evaluation of structural robustness basedon internal energy distribution2011Manuscript (preprint) (Other academic)
    Abstract [en]

    Robustness evaluations give valuable information about the sensitivity of a structure to stochastic variation of design parameters, but are in general expensive to perform due to the extensive number of function evaluations required. Therefore, an Internal Energy Based (IEB) method is presented here, in which the structural sensitivity to variation of each thickness parameter is estimated based on the internal energy distribution obtained from one single function evaluation. In this way, the cost of such structural robustness evaluations is significantly reduced. However, the accuracy of the IEB method depends on the structural behaviour. Here it is tested for two structures with nonlinear displacement responses caused by impact loads. The method is however believed to be applicable to any structure exposed to a single load acting on a limited area of the structure, and for response functions related to the displacement of the loaded area.

  • 28726.
    Öman, Michael
    et al.
    Scania CV AB, Södertälje.
    Nilsson, Larsgunnar
    Linköping University, Department of Management and Engineering, Solid Mechanics. Linköping University, The Institute of Technology.
    An improved critical constraint method for structural optimization of product families2012In: Structural and multidisciplinary optimization (Print), ISSN 1615-147X, E-ISSN 1615-1488, Vol. 45, no 2, 235-246 p.Article in journal (Refereed)
    Abstract [en]

    This paper discusses important improvements in the efficient Critical Constraint Method (CCM) for the optimization of structural product families subjected to multiple crash load cases. The method was first presented by Öman and Nilsson (Struct Multidisc Optim 41(5):797–815, 2010). However, the algorithm often converged towards an infeasible solution, which considerably limited the applicability of the method. Therefore, improvements are presented here to make the method more robust regarding feasible solutions, resulting in only a minor decrease in efficiency compared to the original method. The improvements include; a penalty approach to control the feasibility of the method by continuously pushing the solution out of the infeasible region, a dynamic contraction algorithm to increase the accuracy and robustness of the method by considering the optimization progress and variable history in the reduction of the step size, and the implementation of a parallel approach to further increase the efficiency of the method by enabling the full potential of large-scale computer clusters. Finally, the potential of the improved CCM algorithm is demonstrated on a large-scale industrial family optimization problem and it is concluded that the high efficiency of the method enables the usage of large product family optimization in the design process.

  • 28727.
    Öman, Michael
    et al.
    Linköping University, Department of Management and Engineering, Solid Mechanics. Linköping University, The Institute of Technology.
    Nilsson, Larsgunnar
    Linköping University, Department of Management and Engineering, Solid Mechanics. Linköping University, The Institute of Technology.
    Structural optimization based on internal energy distribution2011Manuscript (preprint) (Other academic)
    Abstract [en]

    Structural optimization is a valuable tool to improve the performance of products, but it is in general expensive to perform due to the required extensive number of function evaluations. Therefore, an approximate method based on the internal energy distribution, which only requires a small number of function evaluations, is presented here. By this method, structural optimization can be enabled already in the initial steps in the design of new products when fast, but not necessarily precise, results are often desired. However, the accuracy of the approximate solution depends on the structural behaviour. The internal energy based optimization method is here validated for three structures, but it is believed to be applicable to any structure subjected to a single load where the functions considered are related to the displacement of the loaded area and/or the material thicknesses of the structural parts.

  • 28728.
    Öman, Michael
    et al.
    Linköping University, Department of Management and Engineering, Solid Mechanics. Linköping University, The Institute of Technology.
    Nilsson, Larsgunnar
    Linköping University, Department of Management and Engineering, Solid Mechanics. Linköping University, The Institute of Technology.
    Structural optimization of product families subjected to multiple crash load cases2010In: Structural and multidisciplinary optimization (Print), ISSN 1615-147X, E-ISSN 1615-1488, Vol. 41, no 5, 797-815 p.Article in journal (Refereed)
    Abstract [en]

    This paper discusses the problem of structural optimization of product families subjected to multiple load cases, evaluated by computationally costly finite element analysis. Product families generally have a complex composition of shared components that makes individual product optimization difficult as the relation between the shared variables is not always intuitive. More optimal is to treat the problem as a product family optimization problem. Though, for product families subjected to multiple and computationally costly crash loads, the optimization problem takes too long time to solve with traditional methods. Therefore, a new optimization algorithm is presented that decomposes the family problem into sub-problems and iteratively reduces the number of sub-problems, decouple and solve them. The algorithm is applicable for module based product families with predefined composition of generalized commonality, subjected to multiple load cases that can be analyzed separately. The problem reduction is performed by only considering the constraints that are critical in the optimal solution. Therefore the optimization algorithm is called the Critical Constraint Method, CCM. Finally the CCM algorithm is evaluated by two product family optimization problems.

  • 28729.
    Örn, Markus
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, The Institute of Technology.
    Towards Better Alternator Efficiency2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The requirements on vehicle industry are constantly getting stricter, especially when it comes to emissions. At the same time cars, trucks and buses are needed for our way of living. This have forced companies to be as ecient as possible in their way of using fossil fuels for travelling and transport. To increase the eciency companies investigate all possible fuel savings to decrease their carbon footprint as much as possible. One area of savings that is not that obvious to many people is the alternator. Several percent of the total energy used by a vehicle are needed to operate the alternator. With a typical alternator eciency of 70% considerable savings can be achieved.

    This thesis that concern alternator eciency was carried out at Scania in Södertälje, Sweden. The goal of the thesis is to construct a mathematical model of an alternator. The model is supposed to consider all losses in the alternator and together with the output power give an eciency model of the alternator at different speeds and loads. A great part of the project has been dealing with the magnetic losses. The magnetic losses have been modeled as an equivalent circuit with the load angle as a central piece. The equivalent circuit is built up by the fact that the alternator used in the vehicles is a salient pole alternator. The equivalent circuit describes a voltage equation where the voltage drop over the magnetic inductance is described. From that relations between the signals in the alternator and output signals can be written.

    The alternator model is then used together with data recorded from different buses all over the world, this to be able to investigate how the alternator contributes to the fuel consump- tion depending on the way that the buses are driven.

    The result of this thesis is a mathematical model that describes the losses in the alternator for different load cases and speeds. 

  • 28730.
    Örn, Sara
    Linköping University, Department of Electrical Engineering, Communication Systems. Linköping University, The Institute of Technology.
    Realistic Multi-Cell Interference Coordination in 4G/LTE2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In the LTE mobile system, all cells use the same set of frequencies. This means that a user could experience interference from other cells. A method that has been studied in order to reduce this interference and thereby increase data rate or system throughput is to coordinate scheduling between cells. Good results of this have been found in different studies. However, the interference is generally assumed to be known. Studies using estimated interference and simulating more than one cluster of cells have found almost no gain.

    This thesis will focus on how to use information from coordinated scheduling and other traffic estimates to do better interference estimation and link adaption. The suggested method is to coordinate larger clusters and use the coordination information, as well as estimates of which cells will be transmitting, to make estimates of interference from other cells. The additional information from interference estimation is used in the link adaptation. Limitations in bandwidth of the backhaul needed to send data between cells are considered, as well as the delay it may introduce. A limitation of the scope is that MIMO or HetNet scenarios have not been simulated.

    The suggested method for interference estimation and link adaptation have been implemented and simulated in a system simulator. The method gives a less biased estimate of SINR, but there are no gains in user bit rate. The lesser bias is since the method is better at predicting high SINR than the base estimate is. The lack of gains regarding user bit rate may result from the fact that in the studied scenarios, users where not able to make use of the higher estimated SINR since the base estimate is already high.

    The conclusion is that the method might be useful in scenarios where there are not full load, but the users either have bad channel quality or are able to make use of very high SINR. Such scenarios could be HetNet or MIMO scenarios, respectively.

  • 28731.
    Örnerheim, Mattias
    Linköping University, Department of Management and Engineering, Political Science. Linköping University, The Institute of Technology.
    Entrepreneurial actors between two systems of norms - Profound and professional quality knowledge in Swedish health care2011Conference paper (Other academic)
  • 28732.
    Örnerheim, Mattias
    Linköping University, Department of Management and Engineering, Political Science. Linköping University, The Institute of Technology.
    Kvalitetsbegreppet i lagstiftningen inom den mänskliga sektorn: - en översikt2013Report (Other (popular science, discussion, etc.))
    Abstract [sv]

    Denna undersökning behandlar hur olika kvalitetsaspekter i några utvalda sektorslagar förhåller sig till varandra inom hälso- och sjukvård, polis- och kriminalvård, utbildning samt vissa kommunala lagar. Alla befinner sig i den s.k. mänskliga sektorn av offentlig verksamhet. Den bakomliggande orsaken till detta är att Innovationsrådet vill fördjupa kunskapen om hur begreppet kvalitet definieras och används i svensk lagstiftning och i förarbetena till vissa lagar. Undersökningen strävar inte efter att generera någon legaldefinition av begreppet kvalitet.

    Kvalitetsbegreppet delas in i aspekterna; struktur, process och resultat i en analysmodell i form av en matris som även tar hänsyn till personal och medborgarperspektiv. Strukturkvalitet speglar förutsättningarna för eller inflödet i en verksamhet, processkvalitet belyser de aktiviteter som görs i verksamheten och resultatkvalitet återger prestationerna och effekterna av verksamheten. Med hjälp av analysmodellen skapas ett mönster över vilka aspekter som tydligast framträder i lagarna och förarbeten samt vilket perspektiv som är mest påtagligt i respektive lag. Genom analysmodellen har en överblick över varje sektor kunnat ges.

    Undersökningen är en dokumentstudie och baseras på lagtexter med relaterade propositioner samt statliga utredningar. De utvalda lagarna återfinns i bilaga 1. I analysen av materialet har först kvantitativa sökningar gjort på kvalitet och relaterade begrepp såsom kvalitetssäkring, kvalitetsgranskning, kvalitetskontroll samt kvalitetsutvärdering för att få en bild av om kvalitet är ett återkommande begrepp eller inte. Därefter har en granskning och tolkning gjorts för att utreda ur vilka aspekter som kvalitet beskrivs, samt vilket perspektiv som väger tyngst i skrivningar i lagen och dess förarbeten.

    Varje sektor är resultatredovisad för sig i särskilda avsnitt. Resultaten visar att kvalitetsbegreppet inom hälso- och sjukvården är frekvent förekommande ur aspekterna struktur och resultat, medan resultatkvalitet överlämnats till den autonoma medicinska professionen att definiera. I utbildningssektorn tycks förhållandet vara det motsatta där resultatkvalitet i form av måluppfyllelse är det centrala och betonas starkt även kvalitet i termer av struktur och process förekommer. Även i denna sektor lyfter lagstiftaren fram autonomi och egenkontroll i avseende på utbildning och forskning när det gäller att definiera vad som är god kvalitet i vetenskapliga processer och resultat.

    Inom socialtjänsten pågår ett arbete som syftar till att ta fram kvalitetsindikatorer ur olika aspekter inspirerat av hälso- och sjukvården. Idag är begreppet kvalitet tydligast uttryckt i socialtjänstlagen när det gäller aspekterna struktur och process i ett personalperspektiv. Även inom polis och kriminalvård tycks kvalitetsbegreppet öka i betydelse även i lagtexterna, där struktur- och processaspekter framkommer i kriminalvårdens nya fängelse- och häkteslagstftningen. I polislagen lyser dock begreppet kvalitet med sin frånvaro, vilket i sig inte hindrar att krav ställs på kvalitet genom andra kanaler.

    Undersökningen avslutas med en diskussion utifrån de sektorsvisa resultaten om behov av ständigt återkommande omprövningar av hur begreppet ska användas i lagen och avvägningar om risken för cementering av verksamheter å ena sida och rättsäkerhet samt tydlighet å den andra.

  • 28733.
    Örnerheim, Mattias
    Linköping University, Department of Management and Engineering, Political Science. Linköping University, The Institute of Technology.
    Marknadsskapande, valfrihet och e-hälsa i sjukvården: Utkast till avhandlingsdesign (lic.)2010Conference paper (Other academic)
  • 28734.
    Örtegren, Jonas
    et al.
    Department of Polymer Technology, Royal Institute of Technology, Sweden.
    Busson, Philippe
    Department of Polymer Technology, Royal Institute of Technology, Sweden.
    Gedde, Ulf W.
    Department of Polymer Technology, Royal Institute of Technology, Sweden.
    Hult, Anders
    Department of Polymer Technology, Royal Institute of Technology, Sweden.
    Eriksson, Anders
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, The Institute of Technology.
    Lindgren, Mikael
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, The Institute of Technology.
    Andersson, Gunnas
    Physics Department, Chalmers University of Technology, Göteborg, Sweden.
    Cone motion viscosity and optical second harmonic generation of ferroelectric liquid crystalline dendrimers2001In: Liquid crystals (Print), ISSN 0267-8292, E-ISSN 1366-5855, Vol. 28, no 6, 861-868 p.Article in journal (Refereed)
    Abstract [en]

    We report second harmonic generation in a ferroelectric liquid crystalline trimer and ferroelectric liquid crystalline dendrimers of first, second and third generation. Thin cells were filled with the compounds by capillary forces at elevated temperature, and cooled from the surface stabilized ferroelectric state to below the glass transition temperature, while kept in an electric field. The cone motion viscosity and the threshold electric field for unwinding of the helix axis of the chiral tilted smectic mesophases were studied separately at elevated temperature, and these data were used to optimize the preparation of the films. The measured response time was between 0.3 and 3ms, which corresponds to a cone motion viscosity between 0.5 and 50 Pa s. Second harmonic generation was studied both at elevated temperature with an electric field and at room temperature with and without electric field. The first generation dendrimer exhibited a strong increase in the second order non-linear optical response with time at room temperature. The d 23-coefficient of this dendrimer was approximately four times larger than for the other macromolecules and was 0.045 pm V-1. The relatively large d-coefficient of the first generation dendrimer is ascribed to crystallization, which improved the orientation of the molecular dipoles.

  • 28735.
    Örtegren, Jonas
    et al.
    Department of Polymer Technology, Royal Institute of Technology, Sweden.
    Busson, Philippe
    Department of Polymer Technology, Royal Institute of Technology, Sweden.
    Gedde, Ulf W.
    Department of Polymer Technology, Royal Institute of Technology, Sweden.
    Hult, Anders
    Department of Polymer Technology, Royal Institute of Technology, Sweden.
    Eriksson, Anders
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, The Institute of Technology.
    Lindgren, Mikael
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, The Institute of Technology.
    Arntzén, Per-Otto
    National Defence Research Establishment, Linköping, Sweden.
    Hermann, David S.
    Physics Department, Chalmers University of Technology,Göteborg, Sweden.
    Rudquist, Per
    Physics Department, Chalmers University of Technology,Göteborg, Sweden.
    Lagerwall, Sven T.
    Physics Department, Chalmers University of Technology,Göteborg, Sweden.
    Time-dependent nonlinear optical properties of pyroelectric liquid crystalline polymers1999In: Macromolecular Symposia, ISSN 1022-1360, E-ISSN 1521-3900, Vol. 148, 179-195 p.Article in journal (Refereed)
    Abstract [en]

    Highly oriented pyroelectric liquid-crystalline polymers were prepared by photopolymerization under the influence of a static electric field from binary mixtures of two acrylate monomers exhibiting chiral smectic C mesomorphism. Both monomers contained nitro groups to yield second order nonlinear optical properties (second harmonic generation) and one of the monomers had two functional groups to yield a crosslinked polymer. The room temperature second order nonlinear susceptibility of the polymers showed during the first two hours a 10 % decrease after which it remained constant during the next 48 days. At elevated temperatures there was a significant difference in the nonlinear optical properties over time between crosslinked and uncrosslinked polymers. The uncrosslinked polymer showed a pronounced loss of second order nonlinear optical activity with time at ≥38°C. The crosslinked polymer showed a much smaller and basically a temperature independent decrease rate in the second order nonlinear optical properties at all the ageing temperatures (23-130°C). Both the loss in mesogen order parameter, very evident for the uncrosslinked polymer, and conformational changes occurring within the mesogens (β mechanism), may account for the observations made.

  • 28736.
    Öst, Gustav
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, The Institute of Technology.
    Search path generation with UAV applications using approximate convex decomposition2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This work focuses on the problem that pertains to area searching with UAVs. Specifically developing algorithms that generate flight paths that are short with- out sacrificing flyability. For instance, very sharp turns will compromise flyability since fixed wing aircraft cannot make very sharp turns. This thesis provides an analysis of different types of search methods, area decompositions, and combi- nations thereof. The search methods used are side to side searching and spiral searching. In side to side searching the aircraft goes back and forth only making 90-degree turns. Spiral search searches the shape in a spiral pattern starting on the outer perimeter working its way in. The idea being that it should generate flight paths that are easy to fly since all turns should be with a large turn radii. Area decomposition is done to divide complex shapes into smaller more manage- able shapes. The report concludes that with the implemented methods the side to side scanning method without area decomposition yields good and above all very reliable results. The reliability stems from the fact that all turns are 90 degrees and that algorithm never get stuck or makes bad mistakes. Only having 90 degree turns results in only four different types of turns. This allows the airplanes behav- ior along the route to be predictable after flying the first four turns. Although this assumes that the strength of the wind is a greater influence than the turbulences effect on the aircraft’s flight characteristics. This is a very valuable feature for an operator in charge of a flight. The other tested methods and area decompositions often yield a shorter flight path, however, despite extensive adjustments to the algorithms they never came to handle all cases in a satisfactory manner. These methods may also generate any kind of turn at any time, including turns of nearly 180 degrees. These turns can lead to an airplane missing the intended flight path and thus missing to scan the intended area properly. Area decomposition proves to be really effective only when the area has many protrusions that stick out in different directions, think of a starfish shape. In these cases the side to side algo- rithm generate a path that has long legs over parts that are not in the search area. When the area is decomposed the algorithm starts with, for example, one arm of the starfish at a time and then search the rest of the arms and body in turn. 

  • 28737.
    Östblom, Mattias
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Sensor Science and Molecular Physics .
    Ekeroth, Johan
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology.
    Konradsson, Peter
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Organic Chemistry .
    Liedberg, Bo
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Sensor Science and Molecular Physics .
    Structure and desorption energetics of ultrathin D2O ice overlay ers on serine- And serinephosphate-terminated self-assembled monolayers2006In: Journal of Physical Chemistry B, ISSN 1520-6106, E-ISSN 1520-5207, Vol. 110, no 4, 1695-1700 p.Article in journal (Refereed)
    Abstract [en]

    This paper reports on the structure and desorption dynamics of thin D 2O ice overlayers (0.2-10 monolayers) deposited on serine- and serinephosphate- (with H+, Na+, Ca2+ counterions) terminated self-assembled monolayers (SAMs). The D2O ice overlayers are deposited on the SAMs at ~85 K in ultrahigh vacuum and characterized with infrared reflection absorption spectroscopy (IRAS). Reflection absorption (RA) spectra obtained at sub-monolayer D2O coverage reveal that surface modes, e.g. free dangling OD stretch, dominate on the serine SAM surface, whereas vibrational modes characteristic for bulk ice are more prominent on the serinephosphate SAMs. Temperature programmed desorption mass spectrometry (TPD-MS) and TPD-IRAS are subsequently used to investigate the energetics and the structural transitions occurring in the ice overlayer during temperature ramping. D2O ice (~2.5 monolayers) on the serine SAMs undergoes a gradual change from an amorphous- to a crystalline-like phase upon increasing the substrate temperature. This transition is not as pronounced on the serine phosphate SAM most likely because of reduced mobility due to strong pinning to the surface. We show also that the energy of desorption for a sub-monolayer of D2O ice on serinephosphate SAM surfaces with a Na+ and Ca2+ counterions is equally high or even exceeds previously reported values for analogous high-energy SAMs. © 2006 American Chemical Society.

  • 28738.
    Östblom, Mattias
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Sensor Science and Molecular Physics .
    Liedberg, Bo
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Sensor Science and Molecular Physics .
    Demers, L.M.
    Department of Chemistry, Center for Nanofabrication and Molecular Self-Assembly, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208.
    Mirkin, C.A.
    Department of Chemistry, Center for Nanofabrication and Molecular Self-Assembly, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208.
    On the structure and desorption dynamics of DNA bases adsorbed on gold: A temperature-programmed study2005In: Journal of Physical Chemistry B, ISSN 1520-6106, E-ISSN 1520-5207, Vol. 109, no 31, 15150-15160 p.Article in journal (Refereed)
    Abstract [en]

    The structure and desorption dynamics of mono- and multilayer samples of adenine, cytosine, guanine, and thymine on polycrystalline gold thin films are studied using temperature-programmed desorption-infrared reflection absorption spectroscopy (TPD-IRAS) and temperature-programmed desorption-mass spectroscopy (TPD-MS). It is shown that the pyrimidines, adenine and guanine, adsorb to gold in a complex manner and that both adhesive (adenine) and cohesive (guanine) interactions contribute the apparent binding energies to the substrate surface. Adenine displays at least two adsorption sites, including a high-energy site (210°C, ~136 kj/mol), wherein the molecule coordinates to the gold substrate via the NH2 group in an sp3-like, strongly perturbed, nonplanar configuration. The purines, cytosine and thymine, display a less complicated adsorption/desorption behavior. The desorption energy for cytosine (160°C, ~122 kJ/mol) is similar to those obtained for adenine and guanine, but desorption occurs from a single site of dispersed, nonaggregated cytosine. Thymine desorbs also from a single site but at a significantly lower energy (100°C, ~104 kJ/mol). Infrared data reveal that the monolayer architectures discussed herein are structurally very different from those observed for the bases in the bulk crystalline state. It is also evident that both pyrimidines and purines adsorb on gold with the plane of the molecule in a nonparallel orientation with respect to the substrate surface. The results of this work are discussed in the context of improving the understanding of the design of capturing oligonucleotides or DNA strands for bioanalytical applications, in particular, for gold nanoparticle-based assays. © 2005 American Chemical Society.

  • 28739.
    Östblom, Mattias
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Sensor Science and Molecular Physics .
    Valiokas, Ramunas
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology.
    Konradsson, Peter
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Organic Chemistry .
    Svensson, Stefan
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Organic Chemistry .
    Liedberg, Bo
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Sensor Science and Molecular Physics .
    Garrett, M.
    Department of Chemistry and Materials Science, Pennsylvania State University, University Park, PA 16802.
    Allara, D.L.
    Department of Chemistry and Materials Science, Pennsylvania State University, University Park, PA 16802.
    Ice nucleation and phase behavior on oligo(ethylene glycol) and hydroxyl self-assembled monolayers: Simulations and experiments2006In: Journal of Physical Chemistry B, ISSN 1520-6106, E-ISSN 1520-5207, Vol. 110, no 4, 1830-1836 p.Article in journal (Refereed)
    Abstract [en]

    The nucleation and phase behavior of ultrathin D2O-ice overlayers have been studied on oligo(ethylene glycol) (OEG)-terminated and hydroxyl self-assembled monolayers (SAMs) at low temperatures in ultrahigh vacuum. Infrared reflection-absorption spectroscopy (IRAS) is used to characterize the ice overlayers, the SAMs, and the interactions occurring between the ice and the SAM surfaces. Spectral simulations, based on optical models in conjunction with Maxwell Garnett effective medium theory, point out the importance of including voids in the modeling of the ice structures, with void fractions reaching 60% in some overlayers. The kinetics of the phase transition from amorphous-like to crystalline-like ice upon isothermal annealing at 140 K is found to depend on the conformational state of the supporting OEG SAM surface. The rate is fast on the helical OEG SAMs and slow on the corresponding all-trans SAMs. This difference in kinetics is most likely due to a pronounced D2O interpenetration and binding to the all-trans segments of the ethylene glycol portion of the SAM. No such penetration and binding was observed on the helical OEG SAM. © 2006 American Chemical Society.

  • 28740.
    Öster, Michael
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Theoretical Physics.
    Nonlinear Localisation in classical lattices2006In: Science and Supercomputing in Europe / [ed] Michael Öster, Bologna: Centro di Calcolo Interuniversitario dell´Italia NordOrientale , 2006, 754-757 p.Chapter in book (Other academic)
    Abstract [en]

  • 28741.
    Öster, Michael
    Linköping University, Department of Physics, Chemistry and Biology, Theoretical Physics. Linköping University, The Institute of Technology.
    Nonlinear localization in discrete and continuum systems: applications for optical waveguide arrays2005Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    An introcludion to the formation of coherent structures in spatially discrete and continuous systems is given. Of special interest is the phenomenon of nonlinear localization, where the self-focusing of an excitation is balanced by a dispersive process. This leads to the existence of localized waves (solitons) in continuous systems, and under very general conditions to intrinsic localized modes (discrete breathers) in systems of coupled anharmonic oscillators. Focus is set on nonlinear Schrödinger equations. A discrete equation, describing the propagation of the electric field in an array of coupled optical waveguides embedded in a material with a nonlinear index of refraction of the Kerr-type, is derived. The equation also describes the evolution of weakly coupled Bose-Einstein condensates in a periodic potential. The model contains nonlinear coupling terms and an effort is made to understand the novel features introduced by these terms as well as the nonlinear dispersion arising from taking the continuum limit of the discrete equation.

    Important contributions in the papers are the discovery of inversion of stability between stationary excitations localized, respectively, on and in between sites in the lattice model for waveguide arrays, leading to an enhanced mobility of highly localized modes. As these can be controlled by simple perturbations. they may have an important applicat ion for optical multiport switching. The nonlinear coupling terms also lead to existence of discrete breathers with compact support and to a new type of stationary, complex, phase-twisted modes not previously reported. Of interest is also the possibility of controlling the magnitude and direction of the norm (Poynting power) current flowing across the waveguide array by simple non-symmetry-breaking perturbations. For the continuum equation, the nonlinear dispersion leads to the formation of exotic solitons, i.e., localized waves with discontinuous derivatives. The emergence of short-wavelength instabilities due to the simultaneous presence of nonlocal and nonlinea.r dispersion is also explained.

  • 28742.
    Öster, Michael
    Linköping University, Department of Physics, Chemistry and Biology, Theoretical Physics . Linköping University, The Institute of Technology.
    Stability and Mobility of Localized and Extended Excitations in Nonlinear Schrödinger Models2007Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    This thesis is mainly concerned with the properties of some discrete nonlinear Schrödinger equations. These naturally arise in many different physical contexts as the limiting form of general dynamical lattice equations that incorporate nonlinearity and coupling. Interest is focused on theoretical models of coupled optical waveguides constructed from materials with a nonlinear index of refraction. In arrays of waveguides the overlap of the evanescent electric field of the modes in neighbouring waveguides provides a coupling and the nonlinearity of the material provides a mechanism to halt the discrete diffraction that otherwise would spread localized energy across the array. In particular, waveguide structures where also a nonlinear coupling is taken into account are studied. It is noted that the equation for the evolution of the complex amplitudes of the electric field along an array of waveguides also can be used to describe the dynamics of Bose-Einstein condensates trapped in a periodic optical potential. Possible excitations in arrays in both one and two dimensions are considered, with emphasis on the effects of the nonlinear coupling.

    Localized excitations are considered from the viewpoint of the theory of discrete breathers, or intrinsic localized modes, i.e., solutions of the dynamical equations that are periodic in time and have a spatial localization. The general theory of such solutions, that appear under very general circumstances in nonlinear lattice equations, is reviewed. In an array of waveguides this means that light can propagate along the array confined essentially to one or a few waveguides. In general a distinction is made between excitations that are centred on a waveguide, or site in the lattice, and excitations that are centred inbetween waveguides. Usually only the former give stable propagation. When the localized beam can be displaced to neighbouring waveguides the array can operate as an optical switch. With the inclusion of nonlinear coupling between the sites, as in the model derived in this thesis, the stability of the site-centred and bond-centred solutions can be exchanged. It is shown how this leads to the existence of highly localized mobile solutions that can propagate transversely in the one-dimensional array of waveguides. The inversion of stability of stationary solutions occurs also in the two-dimensional array, but in this setting it fails to give good mobility of localized excitations. The reason for this is also explained.

    In a two-dimensional lattice a discrete breather can have the form of a vortex. This means that the phase of the complex amplitude will vary on a contour around the excitation, such that the phase is increased by 2πS, where S is the topological charge, on the completion of one turn. Some ring-like vortex excitations are considered and in particular a stable vortex with S=2 is found. It is also noted that the effect of charge flipping, i.e., when the topological charge periodically changes between -S and S, is connected to the existence of quasiperiodic solutions.

    The nonlinear coupling of the waveguide model will also give rise to some more exotic and novel properties of localized solutions, e.g., discrete breathers with a nontrivial phase. When the linear coupling and the nonlinear coupling have opposite signs, there can be a decoupling in the lattice that allows for compact solutions. These localized excitations will have no decaying tail. Of interest is also the flexibility in controlling the transport of power across the array when it is excited with a nonlinear plane wave. It is shown how a change of the amplitude of a plane wave can affect the magnitude and direction of power flow in the array.

    Also the continuum limit of the one-dimensional discrete waveguide model is considered with an equation incorporating both nonlocal and nonlinear dispersion. In general continuum equations the balance between nonlinearity and dispersion can lead to the formation of localized travelling waves, or solitons. With nonlinear dispersion it is seen that these solitons can be nonanalytic and have discontinuous spatial derivatives. The emergence of short-wavelength instabilities due to the simultaneous presence of nonlocal and nonlinear dispersion is also explained.

  • 28743.
    Öster, Michael
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Theoretical Physics . Linköping University, The Institute of Technology.
    Gaididei, Yuri B.
    Informatics and Mathematical Modelling and Department of Physics, The Technical University of Denmark, Lyngby, Denmark.
    Johansson, Magnus
    Linköping University, Department of Physics, Chemistry and Biology, Theoretical Physics . Linköping University, The Institute of Technology.
    Christiansen, Peter L.
    Informatics and Mathematical Modelling and Department of Physics, The Technical University of Denmark, Lyngby, Denmark.
    Nonlocal and nonlinear dispersion in a nonlinear Schrödinger-type equation: exotic solitons and short-wavelength instabilities2004In: Physica D: Nonlinear Phenomena, ISSN 0167-2789, Vol. 198, no 1-2, 29-50 p.Article in journal (Refereed)
    Abstract [en]

    We study the continuum limit of a nonlinear Schrödinger lattice model with both on-site and inter-site nonlinearities, describing weakly coupled optical waveguides or Bose–Einstein condensates. The resulting continuum nonlinear Schrödinger-type equation includes both nonlocal and nonlinear dispersion. Looking for stationary solutions, the equation is reduced to an ordinary differential equation with a rescaled spectral parameter and a single parameter interpolating between the nonlocality and the nonlinear dispersion. It is seen that these two effects give a similar behaviour for the solutions. We find smooth solitons and, beyond a critical value of the spectral parameter, also nonanalytic solitons in the form of peakons and capons. The existence of the exotic solitons is connected to the special properties of the phase space of the equation. Stability is investigated numerically by calculating eigenvalues and eigenfunctions of the linearized problem, and we particularly find that with both nonlocal and nonlinear dispersion simultaneously present, all solutions are unstable with respect to a break-up into short-wavelength oscillations.

  • 28744.
    Öster, Michael
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Theoretical Physics . Linköping University, The Institute of Technology.
    Johansson , Magnus
    Linköping University, Department of Physics, Chemistry and Biology, Theoretical Physics . Linköping University, The Institute of Technology.
    Stability, mobility and power currents in a two-dimensional model for waveguide arrays with nonlinear coupling2009In: Physica D: Non-linear phenomena, ISSN 0167-2789, E-ISSN 1872-8022, Vol. 238, no 1, 88-99 p.Article in journal (Refereed)
    Abstract [en]

    A two-dimensional nonlinear Schrodinger lattice with nonlinear coupling, modelling a square array of weakly coupled linear optical waveguides embedded in a nonlinear Kerr material, is studied. We find that despite a vanishing energy difference (Peierls-Nabarro barrier) of fundamental stationary modes the mobility of localized excitations is very poor. This is attributed to a large separation in parameter space of the bifurcation points of the involved stationary modes. At these points the stability of the fundamental modes is changed and an asymmetric intermediate solution appears that connects the points. The control of the power flow across the array when excited with plane waves is also addressed and shown to exhibit great flexibility that may lead to applications for power-coupling devices. In certain parameter regimes, the direction of a stable propagating plane-wave current is shown to be continuously tunable by amplitude variation (with fixed phase gradient). More exotic effects of the nonlinear coupling terms like compact discrete breathers and vortices, and stationary complex modes with nontrivial phase relations are also briefly discussed. Regimes of dynamical linear stability are found for all these types of solutions.

  • 28745.
    Öster, Michael
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Theoretical Physics . Linköping University, The Institute of Technology.
    Johansson, Magnus
    Linköping University, Department of Physics, Chemistry and Biology, Theoretical Physics . Linköping University, The Institute of Technology.
    Phase twisted modes and current reversals in a lattice model of waveguide arrays with nonlinear coupling2005In: Physical Review E. Statistical, Nonlinear, and Soft Matter Physics: Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics, ISSN 1063-651X, E-ISSN 1095-3787, Vol. 71, no 2, 025601-1--025601-4 p.Article in journal (Refereed)
    Abstract [en]

    We consider a lattice model for waveguide arrays embedded in nonlinear Kerr media. Inclusion of nonlinear coupling results in many phenomena involving complex, phase-twisted, stationary modes. The norm (Poynting power) current of stable plane-wave solutions can be controlled in magnitude and direction, and may be reversed without symmetry-breaking perturbations. Also stable localized phase-twisted modes with zero current exist, which for particular parameter values may be compact and expressed analytically. The model also describes coupled Bose-Einstein condensates.

  • 28746.
    Öster, Michael
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Theoretical Physics .
    Johansson, Magnus
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Theoretical Physics .
    Stability and Mobility of Localised Modes in One- and Two-dimensional DNLS Equations with Non-linear Coupling2006In: SIAM Conference on Nonlinear Waves and Coherent Structures,2006, 2006Conference paper (Other academic)
  • 28747.
    Öster, Michael
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Theoretical Physics . Linköping University, The Institute of Technology.
    Johansson, Magnus
    Linköping University, Department of Physics, Chemistry and Biology, Theoretical Physics . Linköping University, The Institute of Technology.
    Stable stationary and quasiperiodic discrete vortex breathers with topological charge S=22006In: Physical Review E. Statistical, Nonlinear, and Soft Matter Physics: Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics, ISSN 1063-651X, E-ISSN 1095-3787, Vol. 73, no 6, 066608-1--066608-6 p.Article in journal (Refereed)
    Abstract [en]

    We demonstrate the stability of a stationary vortex breather with vorticity S=2 in the two-dimensional discrete nonlinear Schrödinger model for a square lattice and also discuss the effects of exciting internal sites in a vortex ring. We also point out the fundamental difficulties of observing these solutions with current experimental techniques. Instead, we argue that relevant initial conditions will lead to the formation of quasiperiodic vortex breathers.

  • 28748.
    Öster, Michael
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Theoretical Physics . Linköping University, The Institute of Technology.
    Johansson, Magnus
    Linköping University, Department of Physics, Chemistry and Biology, Theoretical Physics . Linköping University, The Institute of Technology.
    Eriksson, Anders
    Enhanced mobility of strongly localized modes in waveguide arrays by inversion of stability2003In: Physical Review E, ISSN 1063-651X, Vol. 67, no 5, 056606-1--056606-8 p.Article in journal (Refereed)
    Abstract [en]

    A model equation governing the amplitude of the electric field in an array of coupled optical waveguides embedded in a material with Kerr nonlinearities is derived and explored. The equation is an extended discrete nonlinear Schrödinger equation with intersite nonlinearities. Attention is turned towards localized solutions and investigations are made from the viewpoint of the theory of discrete breathers (DBs). Stability analysis reveals an inversion of stability between stationary one-site and symmetric or antisymmetric two-site solutions connected to bifurcations with a pair of asymmetric intermediate DBs. The stability inversion leads to the existence of high-intensity narrow mobile solutions, which can propagate essentially radiationless. The direction and transverse velocity of the mobile solutions can be controlled by appropriate perturbations. Such solutions may have an important application for multiport switching, allowing unambiguous selection of output channel. The derived equation also supports compact DBs, which in some sense yield the best possible solutions for switching purposes.

  • 28749.
    Österberg, Emmy
    Linköping University, Department of Physics, Chemistry and Biology, Biotechnology. Linköping University, The Institute of Technology.
    Ro52: Structure and interactions of constructs of RING and B-box2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The ubiquitination process is vital to maintain the protein homeostasis in the cell. With high specificity it regulates degradation of proteins by tagging them with a small protein called ubiquitin. Four proteins are involved to perform the process and in this thesis one of these proteins is studied. This protein is called Ro52 and belongs to the TRIM protein family. It posses E3 ligase activity because of a N-terminal RING-domain and therefore it is responsible for the last step in the ubiquitination process. The structure of Ro52 is not totally solved and the function of the protein’s four domains is not fully understood.

    In this thesis three constructs of two domains from Ro52 (RING and B-box) is investigated by circular dichroism (CD), nuclear magnetic resonance (NMR) spectroscopy and auto-ubiquitination assay by Western blot. The goal was to gain deeper insight in structural and functional properties of these domains.

    In the end only two constructs were investigated because of time limitations. It was shown by NMR that one construct has similar structure as the wild type but lower stability, possibly due to shorter N-terminal region. Comparison of the results from CD measurements showed that the constructs were well structured but did not reveal any significant differences in secondary structure between the constructs. Functional analysis by Western blot encountered unexpected problems and no results were obtained.

    The current thesis provides a basis for further investigation of variant constructs jointly expressing the RING-B-box domains, and shows that even small changes may alter structure and stability in ways that might affect functional properties. 

  • 28750.
    Österberg, Frida
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
    The visual impact of lamination2005Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This scientific study concerns the visual colour effect caused by the thin polyethylene coating extruded on printed packaging material. The origin of the phenomenon is discovered and characterised mathematically. CIE delta E 2000 theory is adapted in the research for mathematical judgement of visual difference. The report handles the procedure of defining the character of the visual distortion and a characterisation of the effect. In this process it discusses areas as dot gain, colour shift and production parameters. It as well covers the background of colour and printing science. The aim of the work is to create a model that predicts the visual effect of lamination in the proofing stage of the production.

572573574575576577 28701 - 28750 of 28828
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