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  • Rakus-Andersson, Elisabeth
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mathematics and Natural Sciences.
    The new approach to the construction of parametric membership functions for fuzzy sets with unequal supports2017In: Knowledge-Based and Intelligent Information & Engineering Systems: Proceedings of the 21st International Conference, KES-20176-8 September 2017, Marseille, France / [ed] Cecilia Zanni-Merk, Claudia Frydman, Carlos Toro, Yulia Hicks, Robert J. Howlett, Lakhmi C. Jain, Elsevier, 2017, Vol. 112, 2057-2065 p., kes17-155Conference paper (Refereed)
    Abstract [en]

    The current research is devoted to developing methods of a novel mathematical interpretation of term-sets of linguistic variables. To the term-sets of the linguistic variables fuzzy sets are assigned. We intend to adopt the π-functions and the π-functions to derive formulas of membership functions of these sets. The fuzzy sets are divided in three families in the case of an odd number of the term-sets. To each family, we assign only one parametric formula, which depends on two parameters: the width of a non-fuzzy set, which contains all supports of the fuzzy sets being representatives of the term-sets, and a number of the term-sets. Provided that the supports of fuzzy sets will be unequal, the membership function of the set, belonging to one of the families, is computed by means of a functional modifier, inserted in the common equation typical of this family. Medical examples explain how to use cumulated membership functions practically. The procedure can be easily computerized.

  • Lennerstad, Håkan
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mathematics and Natural Sciences.
    Spectrums of knowledge types: mathematics, mathematics education and praxis knowledge2008In: Proceedings of MADIF6, Swedish Society for Research in Mathematics Education , 2008Conference paper (Refereed)
    Abstract [en]

    Knowledge in different research paradigms is discussed: mathematics, mathematics education and a paradigm of practical knowledge. I argue that the three paradigms as highly distinct, different and important. They try to cope with entirely different types of knowledge, all highly relevant for mathematics teachers.

    While mathematics is deductive and mathematical education is evidence based, practical knowledge is a type of knowledge that professionals in any profession develop by experience and by exchange with other professionals. It is based on experience more than on written text. It is well known that it to a large extent is difficult to articulate. Such knowledge is also essential in important types of mathematical knowledge. We discuss the role played by vagueness in mathematics. We also discuss linguistic mathematics knowledge which typically is present but mostly unformulated, as the mother tongue.

    I argue that mathematics, pedagogy and mathematics education suffers from drawbacks by being strongly rooted in the positivist tradition, in which knowledge can always be expressed in words – otherwise it is not knowledge. Central aspects of teacher’s day-to-day profession are too complicated to be captured in words. However, work has been done to allow such practical knowledge to be formulated among professionals. I would like to sketch a more fluent cooperation between the paradigms, in which the advantages of all the different knowledge types may interact and become increasingly useful to each other.

    For such an idea to reach reality, an efficient meeting form is needed. The Dialogue Seminar is developed precisely to study and communicate difficult-to-articulate practical knowledge among experienced professionals from different areas, using analogue and metaphor as catalysts. This offers mathematicians, mathematics education researchers, mathematics teachers and teacher students, and others, an excellent opportunity to listen in depth to each other, and to have a dialogue. 

  • Jagtap, Santosh
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Design Creativity: Refined Method of Novelty Assessment2016In: DS 84: Proceedings of the DESIGN 2016 14th International Design Conference / [ed] Marjanović, D.; Štorga, M.; Pavković, N.; Bojčetić, N.; Škec, S., 2016, 1045-1054 p.Conference paper (Refereed)
    Abstract [en]

    Sarkar and chakrabarti (2011) developed a method to assess novelty of ideas and products. Their method has received attention in design research, as indicated by a number of studies referring to or using their method. While their novelty assessment method has received attention, deficiencies were found in it when it was applied in our own studies. It is the purpose of this article to overcome these deficiencies. In total, four modifications have been proposed to their method, and are supported by drawing on examples of products.

  • Gould, Rachael
    Blekinge Institute of Technology, Faculty of Engineering, Department of Strategic Sustainable Development.
    Why choose one sustainable design strategy over another: A decision-support prototype2017In: Proceedings of the 21stInternational Conference on Engineering Design (ICED17), Vol. 5: Design for X, Design to X, 2017, Vol. 5, 111-120 p.Conference paper (Refereed)
    Abstract [en]

    Sustainable design strategies provide tangible ways for integrating sustainability into early phaseproduct design work. Examples include design for remanufacturing and design for the base of thepyramid. There are many such strategies and it is difficult to choose between them. Sustainable productdesign activities also need to be tailored to business priorities. We therefore designed a decision-supportprototype to aid project teams to choose strategies based on relevance to the project in terms of bothbusiness and sustainability value. To design the prototype, we first identified potential strategies fromsustainable product development literature. We then used literature on each of six selected strategies toidentify potential business and sustainability benefits. We developed a way to compare sustainabilityvalue based on a scientifically established definition of sustainability and a lifecycle perspective. Theprototype is designed to be usable by practitioners who are not necessarily sustainable design experts.The prototype was created to enable future work to test ways to integrate the selection of sustainabledesign strategies into the early phases of product design.

  • Eriksson, Mattias
    et al.
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mathematics and Natural Sciences.
    Lennerstad, Håkan
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mathematics and Natural Sciences.
    A new formula for the statistical weight for a sequence of Rydberg levels in an atom or ion2017In: Journal of Physics, Conference Series, ISSN 1742-6588, E-ISSN 1742-6596, no 869Article in journal (Refereed)
    Abstract [en]

    We present a new formula for the total statistical weight of all Rydberg levels Gion (nl, nh ) for which the principal quantum number n is between higher, nh , and a lower, nl , limits. This formula can be used for all atoms in the periodic table and for all corresponding ions.

  • Linde, Peter
    Blekinge Institute of Technology, The Library.
    BTH Newsletter on Science Publishing and Information about research funding: September 20172017Other (Other (popular science, discussion, etc.))
  • Kroon, Martin
    et al.
    Linnaeus University, SWE.
    Andreasson, Eskil
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Persson Jutemar, E.
    Tetra Pak AB, SWE.
    Petersson, V.
    Tetra Pak AB, SWE.
    Persson, L.
    Tetra Pak AB, SWE.
    Dorn, Michael
    Linnaeus University, SWE.
    Olsson, Pär
    Malmö högskola, SWE.
    Anisotropic Elastic-Viscoplastic Properties at Finite Strains of Injection-Moulded Low-Density Polyethylene2017In: Experimental mechanics, ISSN 0014-4851, E-ISSN 1741-2765, 1-12 p.Article in journal (Refereed)
    Abstract [en]

    Injection-moulding is one of the most common manufacturing processes used for polymers. In many applications, the mechanical properties of the product is of great importance. Injection-moulding of thin-walled polymer products tends to leave the polymer structure in a state where the mechanical properties are anisotropic, due to alignment of polymer chains along the melt flow direction. The anisotropic elastic-viscoplastic properties of low-density polyethylene, that has undergone an injection-moulding process, are therefore examined in the present work. Test specimens were punched out from injection-moulded plates and tested in uniaxial tension. Three in-plane material directions were investigated. Because of the small thickness of the plates, only the in-plane properties could be determined. Tensile tests with both monotonic and cyclic loading were performed, and the local strains on the surface of the test specimens were measured using image analysis. True stress vs. true strain diagrams were constructed, and the material response was evaluated using an elastic-viscoplasticity law. The components of the anisotropic compliance matrix were determined together with the direction-specific plastic hardening parameters. © 2017 The Author(s)

  • Johansson, Christian
    et al.
    NODA, SWE.
    Bergkvist, Markus
    NODA, SWE.
    Geysen, Davy
    EnergyVille, BEL.
    De Somer, Oscar
    EnergyVille, BEL.
    Lavesson, Niklas
    Blekinge Institute of Technology, Faculty of Computing, Department of Computer Science and Engineering.
    Vanhoudt, Dirk
    EnergyVille, BEL.
    Operational Demand Forecasting In District Heating Systems Using Ensembles Of Online Machine Learning Algorithms2017In: 15TH INTERNATIONAL SYMPOSIUM ON DISTRICT HEATING AND COOLING (DHC15-2016) / [ed] Ulseth, R, ELSEVIER SCIENCE BV , 2017, 208-216 p.Conference paper (Refereed)
    Abstract [en]

    Heat demand forecasting is in one form or another an integrated part of most optimisation solutions for district heating and cooling (DHC). Since DHC systems are demand driven, the ability to forecast this behaviour becomes an important part of most overall energy efficiency efforts. This paper presents the current status and results from extensive work in the development, implementation and operational service of online machine learning algorithms for demand forecasting. Recent results and experiences are compared to results predicted by previous work done by the authors. The prior work, based mainly on certain decision tree based regression algorithms, is expanded to include other forms of decision tree solutions as well as neural network based approaches. These algorithms are analysed both individually and combined in an ensemble solution. Furthermore, the paper also describes the practical implementation and commissioning of the system in two different operational settings where the data streams are analysed online in real-time. It is shown that the results are in line with expectations based on prior work, and that the demand predictions have a robust behaviour within acceptable error margins. Applications of such predictions in relation to intelligent network controllers for district heating are explored and the initial results of such systems are discussed. (C) 2017 The Authors. Published by Elsevier Ltd.

  • Schwieger, Kay
    et al.
    Iteratec GmbH, GER.
    Wagner, Stefan
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mathematics and Natural Sciences.
    Part III, Free Actions of Compact Quantum Groups on C*-Algebras2017In: SIGMA. Symmetry, Integrability and Geometry, ISSN 1815-0659, E-ISSN 1815-0659, Vol. 13, 62Article in journal (Refereed)
    Abstract [en]

    We study and classify free actions of compact quantum groups on unital C*-algebras in terms of generalized factor systems. Moreover, we use these factor systems to show that all finite coverings of irrational rotation C*-algebras are cleft.

  • Jagtap, Santosh
    et al.
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Larsson, Andreas
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Warell, Anders
    Lund University, SWE.
    Design For Resource-Limited Societies: Informational Behaviour Of Designers2017In: Proceedings of the 21stInternational Conference on Engineering Design (ICED17), Vol. 1: Resource-Sensitive Design | Design Research Applications and Case Studies, 2017Conference paper (Refereed)
    Abstract [en]

    There is a sharp contrast between High Resource Settings (HRSs), commonly seen in developedcountries and Low Resource Settings (LRSs), typically found in the marginalised sections of societiesaround the world. Product design for LRSs is crucial to satisfy unmet or under-served needs of thepeople living in LRSs. Supporting designers to develop successful products for LRSs demandsdeveloping an in-depth understanding of their design process, including their informational behaviour.In this research, using think aloud protocol analysis, we compared the designers’ informationalbehaviour in designing products for LRSs and HRSs, where HRSs is considered a baseline. The findingsindicate that designing products for LRSs is more information intensive, and that it influences theinformational activities of designers, thus indicating potential impact of a resource-setting on the waydesigners deal with information.

  • Public defence: 2017-11-06 10:15 J1640, Karlskrona
    Sandhu, Momin Jamil
    Blekinge Institute of Technology, Faculty of Computing, Department of Creative Technologies. Harman/Becker Automotive Systems GmbH, Karlsbad, Germany.
    On Sequence Design for Integrated Radar and Communication Systems2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The motivation of having a joint radar and communication system on a single hardware is driven by space, military, and commercial applications. However, designing sequences that can simultaneously support radar and communication functionalities is one of the major hurdles in the practical implementation of these systems. In order to facilitate a simultaneous use of sequences for both radar and communication systems, a flexible sequence design is needed.

    The objective of this dissertation is to address the sequence design problem for integrated radar and communication systems. The sequence design for these systems requires a trade-off between different performance measures, such as correlation characteristics, integrated sidelobe ratio, peak-to-sidelobe ratio and ambiguity function. The problem of finding a trade-off between various performance measures is solved by employing meta-heuristic algorithms.

    This dissertation is divided into an introduction and three research parts based on peer-reviewed publications. The introduction provides background on binary and polyphase sequences, their use in radar and communication systems, sequence design requirements for integrated radar and communication systems, and application of meta-heuristic optimization algorithms to find optimal sets of sequences for these systems.

    In Part I-A, the performance of conventional polyphase pulse compression sequences is compared with Oppermann sequences. In Part I-B, weighted pulse trains with the elements of Oppermann sequences serving as complex-valued weights are utilized for the design of integrated radar and communication systems. In Part I-C, an analytical expression for the cross-ambiguity function of weighted pulse trains with Oppermann sequences is derived. Several properties of the related auto-ambiguity and cross-ambiguity functions are derived in Part I-D. In Part II, the potential of meta-heuristic algorithms for finding optimal parameter values of Oppermann sequences for radar, communications, and integrated radar and communication systems is studied. In Part III-A, a meta-heuristic algorithm mimicking the breeding behavior of Cuckoos is used to locate more than one solution for multimodal problems. Further, the performance of this algorithm is evaluated in additive white Gaussian noise (AWGN). It is shown that the Cuckoo search algorithm can successfully locate multiple solutions in both non-noise and AWGN with relatively high degree of accuracy. In Part III-B, the cross-ambiguity function synthesization problem is addressed. A meta-heuristic algorithm based on echolocation of bats is used to design a pair of sequences to minimize the integrated square error between the desired cross-ambiguity function and a synthesized cross-ambiguity function.

  • Johnsson, Mikael
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Innovation Teams: Before Innovation Work is Begun2014In: ISPIM Innovation Symposium; Manchester, 2014Conference paper (Refereed)
    Abstract [en]

    This paper focuses on innovation teams before innovation work is begun.

    The reason is that innovation teams are considered to be successful doing such work.

    However, prior studies show problems in innovation-related-knowledge, -

    knowledge gaps, -information and -awareness why this research aims to

    understand these aspects and how they relate to newly formed innovation team as

    they need to handle these aspects. Two case studies conducted during 1,5 years

    show that a newly formed innovation team is in a very complicated situation where

    the identified aspects relate not only to the individual members but also to the

    team, its context and network within and outside the organization. Practical

    implications for this research could be used when planning-, creating- and

    starting up new innovation teams, helping management and team members to

    understand the complexity, for which a model is developed and described.

  • Johnsson, Mikael
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Important innovation enablers for innovation teams2016In: ISPIM Innovation Symposium; Manchester 2016, Manchester, 2016Conference paper (Refereed)
    Abstract [en]

    This research aims to study if innovation enablers (Enablers), i.e. factors that enable innovation work, are important for innovation teams in on-going innovation work and if lack of Enablers affects innovation projects negatively. The background to this study is that prior research states that numerous factors are important for innovation work, but there’s still knowledge to gain whatever these Enablers are perceived to be important by innovation teams. Data from three innovation teams on-going innovation projects, supported by an external facilitator, were used within this study. The long-term qualitative study shows that all Enablers are important, but also that a facilitator is important. Lack of Enablers may cause negative effects on innovation projects, where nine enablers within this study were identified to be critical for avoiding project delays. Further research is suggested.

  • Johnsson, Mikael
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    The importance of innovation enabler for innovation teams2016Conference paper (Refereed)
    Abstract [en]

    This research aims to study the importance of innovation enablers (Enablers), i.e. factors that enable innovation work, for innovation teams in on-going innovation work and to identify which Enablers that are most important. Prior research states that Enablers are important for innovation work, but there’s still knowledge to gain regarding their relative importance. Data from three innovation teams, supported by an external facilitator, were used within this study. The long-term qualitative study demonstrates that the Enablers’ importance varies, but Collaboration, Dedication and Mind-set were the most important Enablers in general to overcome innovation project related problems. Further research is suggested.

  • Johnsson, Mikael
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    The emergence process of innovation teams2017In: ISPIM Innovation Symposium; Manchester, Manchester: The International Society for Professional Innovation Management (ISPIM) , 2017, 1-9 p.Conference paper (Refereed)
    Abstract [en]

    This research aims to gain knowledge regarding the group development process of newly formed innovation teams. In this comparative research, five multi-functional innovation teams based on voluntary members have been studied in an industrial context, all intending to conduct innovation projects after being educated in innovation management. In total 36 respondents have been studied. Qualitative data have repeatedly been collected from observations, interviews, questionnaires, and notes from team meetings in a timeframe of 6 - 18 month. Three of the teams were created in accordance with an explicit and stepwise methodology to create innovation teams, the other two teams were gathered to a sequence of educational seminars. Significant findings were that the teams created in accordance with the innovation-team-creation-methodology didn’t suffer from group dynamic problems, while the other two teams did. Further, the first three teams started innovation projects while the other two teams did not. Further research is suggested.

  • Moraes, Ana Luiza Dallora
    et al.
    Blekinge Institute of Technology, Faculty of Computing, Department of Computer Science and Engineering.
    Eivazzadeh, Shahryar
    Blekinge Institute of Technology, Faculty of Engineering, Department of Health.
    Mendes, Emilia
    Blekinge Institute of Technology, Faculty of Computing, Department of Computer Science and Engineering. Blekinge Institute of Technology, Faculty of Computing, Department of Software Engineering.
    Berglund, Johan
    Blekinge Institute of Technology, Faculty of Engineering, Department of Health.
    Anderberg, Peter
    Blekinge Institute of Technology, Faculty of Engineering, Department of Health.
    Machine learning and microsimulation techniques on the prognosis of dementia: A systematic literature review2017In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 12, no 6, e0179804Article in journal (Refereed)
    Abstract [en]

    Background Dementia is a complex disorder characterized by poor outcomes for the patients and high costs of care. After decades of research little is known about its mechanisms. Having prognostic estimates about dementia can help researchers, patients and public entities in dealing with this disorder. Thus, health data, machine learning and microsimulation techniques could be employed in developing prognostic estimates for dementia. Objective The goal of this paper is to present evidence on the state of the art of studies investigating and the prognosis of dementia using machine learning and microsimulation techniques. Method To achieve our goal we carried out a systematic literature review, in which three large databases -Pubmed, Socups and Web of Science were searched to select studies that employed machine learning or microsimulation techniques for the prognosis of dementia. A single backward snowballing was done to identify further studies. A quality checklist was also employed to assess the quality of the evidence presented by the selected studies, and low quality studies were removed. Finally, data from the final set of studies were extracted in summary tables. Results In total 37 papers were included. The data summary results showed that the current research is focused on the investigation of the patients with mild cognitive impairment that will evolve to Alzheimer's disease, using machine learning techniques. Microsimulation studies were concerned with cost estimation and had a populational focus. Neuroimaging was the most commonly used variable. Conclusions Prediction of conversion from MCI to AD is the dominant theme in the selected studies. Most studies used ML techniques on Neuroimaging data. Only a few data sources have been recruited by most studies and the ADNI database is the one most commonly used. Only two studies have investigated the prediction of epidemiological aspects of Dementia using either ML or MS techniques. Finally, care should be taken when interpreting the reported accuracy of ML techniques, given studies' different contexts. © 2017 Dallora et al.This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

  • Karlsson, Staffan
    et al.
    Lund Univ, SWE.
    Rahm Hallberg, Ingalill
    Lund Univ, SWE.
    Midlöv, Patrik
    Lund Univ, SWE.
    Fagerstrom, Cecilia
    Blekinge Institute of Technology, Faculty of Engineering, Department of Health.
    Trends in treatment with antipsychotic medication in relation to national directives, in people with dementia: a review of the Swedish context2017In: BMC Psychiatry, ISSN 1471-244X, E-ISSN 1471-244X, Vol. 17, 251Article in journal (Refereed)
    Abstract [en]

    Background: The aim of this study was to explore trends in treatment with antipsychotic medication in Swedish dementia care in nursing homes as reported in the most recent empirical studies on the topic, and to relate these trends to directives from the national authorities. Methods: The study included two scoping review studies based on searches of electronic databases as well as the Swedish directives in the field. Results: During the past decade, directives have been developed for antipsychotic medication in Sweden. These directives were generic at first, but have become increasingly specific and restrictive with time. The scoping review showed that treatment with antipsychotic drugs varied between 6% and 38%, and was higher in younger older persons and in those with moderate cognitive impairment and living in nursing homes for people with dementia. A decreasing trend in antipsychotic use has been seen over the last 15 years. Conclusions: Directives from the authorities in Sweden may have had an impact on treatment with antipsychotic medication for people with dementia. Treatment with antipsychotic medication has decreased, while treatment with combinations of psychotropic medications is common. National directives may possibly be even more effective, if applied in combination with systematic follow-ups.

  • Rudenko, Oleg
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Inhomogeneous Burgers Equation with Modular Nonlinearity: Excitation and Evolution of High-Intensity Waves2017In: Doklady. Mathematics, ISSN 1064-5624, E-ISSN 1531-8362, Vol. 95, no 3, 291-294 p.Article in journal (Refereed)
    Abstract [en]

    Solutions to an inhomogeneous partial differential equation of the second-order like Burgers equation are derived. Instead of the common quadratically nonlinear term, this equation contains the term with modular nonlinearity. This model describes the excitation of elastic waves in dissipative media differently reacting to tensile and compressive stresses. The equation is linear for the functions, preserving the sign. Nonlinear effects are manifested only to alternating functions. The solution for the periodic signal is found. The processes of generation of fundamental and higher harmonics are studied. The stationary wave profile is constructed. For one special kind of right-hand-side of the "modular" equation the solution in the form of S-wave is pointed out which is a bipolar single pulse.

  • Bertoni, Alessandro
    et al.
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Larsson, Tobias
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Larsson, Jonas
    Scania Group, SWE.
    Elfsberg, Jenny
    Volvo Construction Equipment, SWE.
    Mining data to design value: a demonstrator in early design2017Conference paper (Refereed)
    Abstract [en]

    The paper presents a study run to verify the applicability of data mining algorithms as

    decision support in early design stages of a product development project. The paper

    describes a two-stage scenario providing the rationale for the application of data science in

    engineering design. Furthermore, it describes a demonstrator showing how data can be fed

    back to the early design stages and can be used to populate models to reduce uncertainty in

    decision making. A wheel loader for constructions works is the reference product for the

    demonstration. Data mining is applied on a dataset built on machine performances and

    contextual and environmental data. The demonstrator focuses on the estimation of the fuel

    consumption of alternative design concepts and estimates the performance variations given

    different contextual variable. Finally, a way of visualizing the results of the data analysis in

    relation to the tested and expected performances is presented.

  • Tatipala, Sravan
    et al.
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Suddapalli, Nikshep Reddy
    Pilthammar, Johan
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering. Volvo Cars.
    Sigvant, Mats
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering. Volvo Cars.
    Johansson, Christian
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Simulation-Driven Design Approach for Design and Optimization of Blankholder2017In: Journal of Physics: Conference Series (JPCS), 2017Conference paper (Refereed)
    Abstract [en]

    Reliable design of stamping dies is desired for efficient and safe production. The design of stamping dies are today mostly based on casting feasibility, although it can also be based on criteria for fatigue, stiffness, safety, economy. Current work presents an approach that is built on Simulation Driven Design, enabling Design Optimization to address this issue. A structural finite element model of a stamping die, used to produce doors for Volvo V70/S80 car models, is studied. This die had developed cracks during its usage. To understand the behaviour of stress distribution in the stamping die, structural analysis of the die is conducted and critical regions with high stresses are identified. The results from structural FE-models are compared with analytical calculations pertaining to fatigue properties of the material. To arrive at an optimum design with increased stiffness and lifetime, topology and free-shape optimization are performed. In the optimization routine, identified critical regions of the die are set as design variables. Other optimization variables are set to maintain manufacturability of the resultant stamping die. Thereafter a CAD model is built based on geometrical results from topology and free-shape optimizations. Then the CAD model is subjected to structural analysis to visualize the new stress distribution. This process is iterated until a satisfactory result is obtained. The final results show reduction in stress levels by 70% with a more homogeneous distribution. Even though mass of the die is increased by 17 %, overall, a stiffer die with better lifetime is obtained. Finally, by reflecting on the entire process, a coordinated approach to handle such situations efficiently is presented.