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  • 151.
    Liu, Yu
    et al.
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningscentrum för Virtuella system.
    Syberfeldt, Anna
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningscentrum för Virtuella system.
    Strand, Mattias
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningscentrum för Virtuella system.
    A Review of Simulation Based Life Cycle Assessment in Manufacturing Industry2018Ingår i: Advances in Manufacturing Technology XXXII: Proceedings of the 16th International Conference on Manufacturing Research, incorporating the 33rd National Conference on Manufacturing Research, September 11 – 13, 2018, Skövde, Sweden / [ed] Peter Thorvald, Keith Case, Amsterdam, Berlin, Washington,DC: IOS Press, 2018, Vol. 8, s. 381-386Konferensbidrag (Refereegranskat)
    Abstract [en]

    The manufacturing industry has a duty to minimize their environmental impact and more and more legislations include environmental impact evaluations from a life cycle perspective to avoid burden shift. Current manufacturing industry increase their use of computer-based simulations for optimizing production processes. In recent years, a number of studies have been published, combining simulations with life cycle assessments (LCA), to evaluate and minimize the environmental impact of production activities, as part of improving the production processes. Still, current knowledge concerning simulations for LCA is rather scattered. Therefore, this paper reviews relevant literature covering simulation based LCA for production development. The results of the review and cross comparison of papers are structured following the 6 categories in line with the ISO standard definition of LCA (goal formulation, scope definition, environmental impact assessment, data quality, level of modelling details, and model validation) and report the strengths and constraints of the reviewed studies. 

  • 152.
    Liu, Yu
    et al.
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningscentrum för Virtuella system.
    Syberfeldt, Anna
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningscentrum för Virtuella system.
    Strand, Mattias
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningscentrum för Virtuella system.
    Review of simulation-based life cycle assessment in manufacturing industry2019Ingår i: Production & Manufacturing Research, ISSN 2169-3277, Vol. 7, nr 1, s. 490-502Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The manufacturing industry has a duty to minimize its environmental impact, and an increasing body of legislation mandates environmental impact evaluations from a life cycle perspective to prevent burden shift. The manufacturing industry is increasing its use of computer-based simulations to optimize production processes. In recent years, several published studies have combined simulations with life cycle assessments (LCAs) to evaluate and minimize the environmental impact of production activities. Still, current knowledge of simulations conducted for LCAs is rather disjointed. This paper accordingly reviews the literature covering simulation-based LCAs of production processes. The results of the review and cross-comparison of papers are structured in terms of seven elements in line with the ISO standard definition of LCA and report the strengths and limitations of the reviewed studies. © 2019, © 2019 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.

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    fulltext
  • 153.
    Mahdavian, Nafise
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningscentrum för Virtuella system.
    Development and Evaluation of Digital Ergonomics Tools to Assess Human Work in Real and Virtual Environments: Based on case studies of manual assembly in Swedish automotive companies2018Rapport (Övrigt vetenskapligt)
    Abstract [en]

    ‘Digital ergonomics tools’ is a term used in this research proposal to refer to tools that are used to assess human work in real and virtual environments, where ‘digital’ refers to the use of technology such as computers, sensors, simulation, and data processing, to achieve desired functionality and usability. Digital ergonomics tools are considered as part of the ‘digital factory’. In essence the digital factory is an advanced computer model that either represents a non-yet existing factory, or an existing factory. When the factory is realised, there is an information flow between the real and the digital factory. The digital factory can be used to be informed about status of running production, and to support product and manufacturing development activities to test different design scenarios in the digital model before realising the selected solutions in the real factory. Hence, the digital factory approach assists designers, engineers, ergonomists, and managers to get a better understanding of the current status of the factory, and offers a digital model for testing and deciding upon different design alternatives. In an ergonomics context, such status checks can be related to assessing current ergonomics loads of the work force, or related to ensuring appropriate ergonomics when workstations are introduced or modified due to new product type introductions. However, there is a need to develop and evaluate digital ergonomics tools that has the desired functionality and usability to be integrated in to the digital factory concept. This proposed research addresses those needs.

    The research contributes to advance knowledge about technology and methods for the assessment of human work in real and virtual environments. The research will be carried out in association with development and evaluation research projects in the area of digital ergonomics tools, such as digital human modelling (DHM) tools and smart workwear. Simulation and experiment based strategies will be used to gather data and extract new knowledge. The studies will be carried out both in simulation and laboratory environments at the University, as well as in case studies in manual assembly in Swedish automotive companies.

  • 154.
    Mahdavian, Nafise
    et al.
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningscentrum för Virtuella system.
    Lind, Carl Mikael
    Unit of Occupational medicine, Karolinska Institutet, Stockholm, Sweden / Division of Ergonomics, KTH Royal Institute of Technology, Huddinge, Sweden.
    Diaz Olivares, Jose Antonio
    Division of Ergonomics, KTH Royal Institute of Technology, Huddinge, Sweden.
    Iriondo Pascual, Aitor
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningscentrum för Virtuella system.
    Högberg, Dan
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningscentrum för Virtuella system.
    Brolin, Erik
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningscentrum för Virtuella system.
    Yang, Liyun
    Unit of Occupational medicine, Karolinska Institutet, Stockholm, Sweden / Division of Ergonomics, KTH Royal Institute of Technology, Huddinge, Sweden.
    Forsman, Mikael
    Unit of Occupational medicine, Karolinska Institutet, Stockholm, Sweden / Division of Ergonomics, KTH Royal Institute of Technology, Huddinge, Sweden.
    Hanson, Lars
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningscentrum för Virtuella system. Scania CV, Södertälje, Sweden.
    Effect of Giving Feedback on Postural Working Techniques2018Ingår i: Advances in Manufacturing Technology XXXII: Proceedings of the 16th International Conference on Manufacturing Research, incorporating the 33rd National Conference on Manufacturing Research, September 11–13, 2018, University of Skövde, Sweden / [ed] Peter Thorvald, Keith Case, Amsterdam, Netherlands: IOS Press, 2018, s. 247-252Konferensbidrag (Refereegranskat)
    Abstract [en]

    Working postures and movements affect work efficiency and musculoskeletal health. To reduce the biomechanical exposure in physically demanding settings, working techniques may be improved by giving instant ergonomic feedback to the operator. This study investigates if feedback can be used to decrease adverse postures and movements in assembly work. A prototype solution of a smart textile workwear was used on a trainee assembly line. Posture and movement signals of 24 trainee operators were sampled via the workwear, transferred to a tablet for analyses and used to provide feedback suggesting improvements of work technique. Two modes of feedback were tested. Every participant’s work technique was measured before and after receiving the feedback and the results were compared. For upper arm elevation angle ≥60, behaviour change is indicated, supporting a positive work technique change, and indicated a future usefulness of technical automatic feedback for operators.

  • 155.
    Marcus, Hesselgren
    et al.
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap.
    Vestberg, Victor
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap.
    Reducering av ställtider: Verktygshantering2018Självständigt arbete på grundnivå (högskoleexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Det här examensarbetet är utfört på ett legotillverkande företag och de arbetar bland annat med avverkande bearbetning, vilket detta arbete har fokuserat på. Produktionen som bedrivs på företaget brukar kallas för HVLV produktion. Det innebär att företaget oftast har nyproduktion på sina detaljer och att de återkommande arbeten som finns är väldigt få, vilket resulterar i långa ledtider.

    Syftet med detta examensarbete var att identifiera vilka aktiviteter som operatörerna lägger mest tid på och därefter välja fokusområde. Vidare kunna kartlägga valt fokusområde ”ställ” med tidsstudier och spagettidiagram för att definiera mer specifika mål. Reducera antalet verktygsrelaterade aktiviteter som sker under ett ställ med 50%, reducera förflyttningar mellan maskin och ställplats med 75% och letandet av verktyg under ett ställ med 50% var de mål som låg till grund för arbetet. För att uppnå dessa mål har några förbättringsförslag tagits fram. 14 stycken verktyg som alltid ska sitta i maskinerna, så kallade standardverktyg har valts ut och implementerats. Tillhörande verktygslistor med relevant information om verktygen och dess utformning har även skapats för att underlätta för operatörerna. Verktygen är utvalda med flexibilitet i fokus för att passa Kramers HVLV produktion, detta via inköpspris, mest köpta verktyg från största verktygsleverantören, bearbetningstid och operatörernas egna erfarenheter. Utifrån standardverktygen har en rutin skapats som operatörerna skall följa från att de programmerat en detalj tills det är dags att starta maskinen.

    En genomgång av tidigare arbeten gjordes för att se i vilken utsträckning valda standardverktyg hade gått att använda. Vilket visade att 40% av de tidigare genomgångna arbetena hade gått att tillverka enbart med utvalda standardverktyg. Vidare gjorde en teoretisk jämförelse med tidigare kartläggning som visar att via standardverktygen och rutinen kunde antalet verktygsrelaterade aktiviteter reduceras med cirka 40%. Detta till största del för att oklarheterna angående vilka verktyg som sitter i maskinerna och i vilken hållare eliminerats. Därmed elimineras också letande av verktyg där målet var satt till en reducering på 50%. Sett till kartläggningen av ställen gör operatören fler förflyttningar till maskinen än vad det är verktyg som skall ställas. Om operatörerna följer rutinen och använder sig av verktygsvagnen krävs endast en förflyttning till maskinen efter att alla verktyg är ställda. Detta medför en kraftig reducering av förflyttningar till och från maskinen. Resultatet visar att cirka 90% av förflyttningarna under ett av de kartlagda ställen hade gått att reducera.

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    Reducering av ställtider
  • 156.
    Mattsson, Sandra
    et al.
    Chalmers University of Technology.
    Fast-Berglund, Åsa
    Chalmers University of Technology.
    Li, Dan
    Chalmers University of Technology.
    Thorvald, Peter
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningscentrum för Virtuella system.
    Forming a cognitive automation strategy for Operator 4.0 in complex assembly2020Ingår i: Computers & industrial engineering, ISSN 0360-8352, E-ISSN 1879-0550, Vol. 139, artikel-id 105360Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Due to today’s technological advances in the area of Industry 4.0, having a strategy for cognitive automation solutions is crucial. Operator 4.0, will have handle and manage different work tasks ranging from learning new tasks to solving difficult problems and initiate changes. To support the operator moving between these tasks a strategy for the design of cognitive automation solutions is needed. The suggested strategy has three steps: 1) select assembly phases, 2) choose level of cognitive automation carrier and 3) suggest cognitive automation content. It is important that the operator is part of the design and that the solution supports movement between the phases learning, operational and disruptive phases. The strategy could support manufacturing companies meeting challenges regarding social sustainability e.g. stress, attractive workplaces and demography changes as well as system transparency and complexity.

  • 157.
    Mattsson, Sandra
    et al.
    Chalmers University of Technology, Gothenburg, Sweden.
    Fast-Berglund, Åsa
    Chalmers University of Technology, Gothenburg, Sweden.
    Thorvald, Peter
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningscentrum för Virtuella system.
    A Relationship Between Operator Performance and Arousal in Assembly2016Ingår i: Procedia CIRP, ISSN 2212-8271, E-ISSN 2212-8271, Vol. 44, s. 32-37Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In order to meet the challenges of future complex systems, manufacturing companies need to better understand how social sustainability affects the operator. One way of studying this is to investigate the possible relationships between operator performance and emotion in an assembly experiment. 60 participants took part in an experiment to investigate the relationships between operator performance and objective and subjective arousal. Results showed a weak relationship between operator performance and objective arousal but no significant relationship was found between performance and subjective arousal. The relationships indicate that further studies on operator emotion could be important to better assembly performance. A tool for doing this might be the Qsensor used in this experiment (measure of objective arousal). More studies are needed to further investigate found relationship and if objective emotion measures can be used to predict performance at assembly workstations.

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  • 158.
    Mårdberg, Peter
    et al.
    Fraunhofer-Chalmers Research Centre for Industrial Mathematics, Gothenburg, Sweden.
    Carlson, Johan S.
    Fraunhofer-Chalmers Research Centre for Industrial Mathematics, Gothenburg, Sweden.
    Bohlin, Robert
    Fraunhofer-Chalmers Research Centre for Industrial Mathematics, Gothenburg, Sweden.
    Delfs, Niclas
    Fraunhofer-Chalmers Research Centre for Industrial Mathematics, Gothenburg, Sweden.
    Gustafsson, Stefan
    Fraunhofer-Chalmers Research Centre for Industrial Mathematics, Gothenburg, Sweden.
    Högberg, Dan
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningscentrum för Virtuella system.
    Hanson, Lars
    Department of Product and Production Development, Chalmers University of Technology, Gothenburg, Sweden / Industrial Development, Scania CV, Sweden.
    Using a formal high-level language and an automated manikin to automatically generate assembly instructions2014Ingår i: International Journal of Human Factors Modelling and Simulation, ISSN 1742-5549, Vol. 4, nr 3/4, s. 233-249Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This paper presents an approach to automatically generate predetermined motion time system (PMTS) based assembly instruction lists from simulations within digital human modelling (DHM) software. A formal high-level instruction language is used to instruct an automated manikin to perform assembly operations. The manikin, the language and the assembled objects are composed into a discrete model. In a post-computational step, the model is used to construct PMTS instruction lists by mapping the manikin motions, assembled objects and the language instructions onto a set of PMTS keywords. The described approach is implemented in the DHM software IMMA and tested on industrial cases of manual assembly in the automotive industry.

  • 159.
    Nackfors, Glenn
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap.
    Factory optimization using DES2016Självständigt arbete på avancerad nivå (magisterexamen), 15 poäng / 22,5 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Discrete Event Simulation (DES) has been a powerful tool for modeling and optimization of production lines for many years. Developing detailed models may be very time consuming and might also be computationally costly to execute, especially if optimization techniques are to be applied. Aggregation techniques, simplifying a detailed system into fewer objects, can be an effective method to reduce the required computational resources as well as a way to shorten the development time. An aggregated model can be used to identify the main constraints in a system, dimensioning inter-line buffers, and focus development activities on the critical issues from a system performance perspective.

    An aggregated model of a real-world plant wide production system has already been developed in the discrete event simulation software FACTS Analyzer. Due to the limitations of FACTS Analyzer this model was instead rebuilt using the discrete event simulation software Plant Simulation which, while less user friendly, has much more configuration options. This model is then validated against the FACTS Analyzer model to ensure accurate results that can be implemented on a real life system.

    In addition some typical optimization experiments are carried out on the Plant Simulation model and the results analyzed. The first of these optimizations alters the buffer sizes to find the minimum amount of buffer capacity needed to get the minimum lead time while maintaining the highest possible throughput. The second optimization uses the same parameters but also adds alteration of the batch size. Both of these optimizations shows that it is possible to get better results with lower settings on both the buffer capacity and batch size then the default value.

    At the end of the report the project is evaluated and conclusions are drawn on what can be improved in the model, such as adding more streamlined updating of variant sequence.  Additionally future experiments that can be interesting to look at is specified based upon the results from the project.  

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    Factory optimization using DES
  • 160.
    Nackfors, Glenn
    et al.
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap.
    Hodo, Damir
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap.
    Utveckling av ett standardiserat operatörsobjekt i plant simulation2015Självständigt arbete på grundnivå (kandidatexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Examensarbetet inom automatiseringsteknik på 30hp är genomfört vid Volvo Cars Coperation (VCC) i Skövde i samarbete med Högskolan i Skövde. 

    Med dagens bemanningsmetod upplever VCC svårigheter med att uppnå en optimal beläggning på operatörerna, då det har varit problematiskt att få fram hur mycket arbete en operatör klarar av. Operatörer är en ofta förbisedd del av simulering eftersom de är komplexa att modellera. Det genomförda examensarbetet består av att utveckla ett standardiserat operatörsobjekt i simuleringsmjukvaran Plant Simulation från Siemens. Med hjälp av detta objekt ska det bli enklare att bemanna effektivt med avseende på antal arbetsområden, operatörernas kompetens samt hur många operatörer det krävs per arbetsområde.

    I VCCs egenutvecklade bibliotek i Plant Simulation fanns det redan ett objekt för operatörer. Detta objekt användes som grund för utveckling av det nya operatörsobjektet. Vid utveckling av det nya objektet utfördes datainsamling i form av både kvalitativ och kvantitativ art för att ta reda på vilken funktionalitet som det nya objektet skulle inneha. Det existerande objektet utvärderades mot dessa funktionalitetskrav för att bestämma vad som skulle läggas till, tas bort eller ändras. Fem stycken huvudområden ansågs vara viktiga att utveckla: (1) operatörer som kan arbeta över två eller flera arbetsområden, (2) gångtid för operatörer från och till operationer, (3) kompetens för operatörerna, (4) inlärningskurva för operatörerna och (5) operatörer som jobbar på olika skift. Av dessa implementerades alla utan inlärningskurvan fullt ut, inlärningskurvan är en del av det fortsatta arbetet.

    För att kunna testa och analysera objektet genomfördes tre stycken experiment i form av fallstudier varav en av dessa fallstudier var av en verklig produktionslinje. Experimentplanen togs fram gemensamt med VCC referensgrupp och Högskolan i Skövde. Huvudmålen med experimenten var att minska antalet operatörer och att öka takt per timma. Resultatet av optimeringen för den verkliga produktionslinjen visade att en signifikant mindre bemanning skulle kunna uppnås utan en större effekt på takt per timma.

    Resultatet av projektet var ett standardiserat operatörsobjekt som togs fram enligt de specifikationer och mål som definierats för projektet. Detta objekt ger möjligheten att snabbare och enklare implementera operatörer i en simuleringsmodell. För att verifiera användbarheten av operatörsobjektet, importerades det och användes för simulering-baserad optimering i tre olika simuleringsmodeller. Operatörsobjektet innehåller också funktionaliteter som ger mer realistiska operatörer så som gångtid till operationer, operatörer som kan arbeta över flera arbetsområden, kompetens för operatörer samt inlärning.

    Resultatet från detta projekt innebär en enklare implementering av operatörer i en simuleringsmjukvara och bidrar således till mer realistiska simuleringsmodeller. 

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    DEVELOPMENT OF A STANDARIZED OPERATOR OBJECT IN PLANT SIMULATION
  • 161.
    Ng, Amos H. C.
    et al.
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningscentrum för Virtuella system.
    Bernedixen, Jacob
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningscentrum för Virtuella system. Volvo Car Corporation, Sweden.
    Pehrsson, Leif
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningscentrum för Virtuella system. Volvo Car Corporation, Sweden.
    What Does Multi-Objective Optimization Have to Do with Bottleneck Improvement of Production Systems?2014Ingår i: Proceedings of The 6th International Swedish Production Symposium 2014 / [ed] Johan Stahre, Björn Johansson & Mats Björkman, 2014Konferensbidrag (Refereegranskat)
    Abstract [en]

    Bottleneck is a common term used to describe the process/operation/person that constrains the performance of the whole system. Since Goldratt introduced his theory of constraint, not many will argue about the importance of identifying and then improving the bottleneck, in order to improve the performance of the entire system. Nevertheless, there exist various definitions of bottleneck, which make bottleneck identification and improvement not a straightforward task in practice. The theory introduced by Production Systems Engineering (PSE) that the bottleneck of a production line is where the infinitesimal improvement can lead to the largest improvement of the average throughput, has provided an inspirational and rigorous way to understand the nature of bottleneck. This is because it conceptually puts bottleneck identification and improvement into a single task. Nevertheless, it is said that a procedure to evaluate how the efficiency increase of each machine would affect the total performance of a line is hardly possible in most practical situations. But is this true?In this paper, we argue how multi-objective optimization fits nicely into the theory introduced by PSE and hence how it can be developed into a practical bottleneck improvement methodology. Numerical results from a real-world application study on a highly complex machining line are provided to justify the practical applicability of this new methodology.

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    fulltext
  • 162.
    Ng, Amos H. C.
    et al.
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningscentrum för Virtuella system.
    Shaaban, Sabry
    Department of Strategy, ESC La Rochelle, La Rochelle, France.
    Bernedixen, Jacob
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningscentrum för Virtuella system.
    Studying unbalanced workload and buffer allocation of production systems using multi-objective optimisation2017Ingår i: International Journal of Production Research, ISSN 0020-7543, E-ISSN 1366-588X, Vol. 55, nr 24, s. 7435-7451Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Numerous studies have investigated the effects of unbalanced service times and inter-station buffer sizes on the efficiency of discrete part, unpaced production lines. There are two main disadvantages of many of these studies: (1) only some predetermined degree of imbalance and patterns of imbalance have been evaluated against the perfectly balanced configuration, making it hard to form a general conclusion on these factors; (2) only a single objective has been set as the target, which neglects the fact that different patterns of imbalance may outperform with respect to different performance measures. Therefore, the aim of this study is to introduce a new approach to investigate the performance of unpaced production lines by using multiple-objective optimisation. It has been found by equipping multi-objective optimisation with an efficient, equality constraints handling technique, both the optimal pattern and degree of imbalance, as well as the optimal relationship among these factors and the performance measures of a production system can be sought and analysed with some single optimisation runs. The results have illustrated that some very interesting relationships among the key performance measures studied, including system throughput, work-in-process and average buffer level, could only be observed within a truly multi-objective optimisation context. While these results may not be generalised to apply to any production lines, the genericity of the proposed simulation-based approach is believed to be applicable to study any real-world, complex production lines.

  • 163. Ng, Amos H. C.
    et al.
    Urenda Moris, Matias
    Svensson, Jacob
    Multi-Objective Simulation Optimization for Production Systems Design using FACTS Analyser2008Ingår i: Proceedings of the 2nd Swedish Production Symposium, 2008, s. 101-109Konferensbidrag (Refereegranskat)
    Abstract [en]

    This paper proposes a new general method for supporting production systems design within the context of Multi-objective Simulation Optimisation. Under this framework, different Production Control Mechanisms can be compared based on their optimal settings, which will be illustrated with a pedagogical simple flow line as well as an engines assembly line in automotive industry. Results from these case studies have provided significant insight into the importance of applying MOSO for Multi-Criteria Decision Making in general production systems design. At the same time, it also outlines the concept of applying significant dominance to handle uncertainty from stochastic simulation output, which has been implemented into a Web-based DES system called FACTS Analyser, specifically designed for conceptual factory design, analysis and optimisation.

  • 164.
    Ng, Amos H.C.
    et al.
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningscentrum för Virtuella system. School of Engineering, Jönköping University, Sweden .
    Bandaru, Sunith
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningscentrum för Virtuella system.
    Frantzén, Marcus
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningscentrum för Virtuella system. Volvo Car Corporation, Sweden .
    Innovative Design and Analysis of Production Systems by Multi-objective Optimization and Data Mining2016Ingår i: Procedia CIRP, ISSN 2212-8271, E-ISSN 2212-8271, Vol. 50, s. 665-671Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This paper presents an innovative approach for the design and analysis of production systems using multi-objective optimization and data mining. The innovation lies on how these two methods using different computational intelligence algorithms can be synergistically integrated and used interactively by production systems designers to support their design decisions. Unlike ordinary optimization approaches for production systems design which several design objectives are linearly combined into a single mathematical function, multi-objective optimization that can generate multiple design alternatives and sort their performances into an efficient frontier can enable the designer to have a more complete picture about how the design decision variables, like number of machines and buffers, can affect the overall performances of the system. Such kind of knowledge that can be gained by plotting the efficient frontier cannot be sought by single-objective based optimizations. Additionally, because of the multiple optimal design alternatives generated, they constitute a dataset that can be fed into some data mining algorithms for extracting the knowledge about the relationships among the design variables and the objectives. This paper addresses the specific challenges posed by the design of discrete production systems for this integrated optimization and data mining approach and then outline a new interactive data mining algorithm developed to meet these challenges, illustrated with a real-world production line design example.

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  • 165.
    Ng, Amos H.C.
    et al.
    Högskolan i Skövde, Forskningscentrum för Virtuella system. Högskolan i Skövde, Institutionen för ingenjörsvetenskap.
    Skoogh, Anders
    Chalmers University of Technology, Gothenburg, Sweden.
    Lämkull, Dan
    Volvo Car Corporation, Gothenburg, Sweden.
    Optimal Maintenance Resources Allocation Using Automated Simulation-based Optimisation and Data Management2015Ingår i: Simulation in Production and Logistics 2015 / [ed] Markus Rabe, Uwe Clausen, Stuttgart: Fraunhofer IRB Verlag, 2015, s. 437-446Konferensbidrag (Refereegranskat)
    Abstract [en]

    This paper introduces a Streamlined Modelling and Decision Support (StreaMod) approach in which input data management, simulation model generation/update and simulation-based optimisation are synergistically integrated into a largely automated process. The aim of this automated process is to support decision making related to the optimal maintenance resources allocation that could improve the performance of production/logistics systems. The basic novelty of the StreaMod optimisation methodology lies on the formulation of an optimal maintenance allocation problem of a production/logistic system into a bi-objective optimisation problem, so that optimal resources/changes to improve the throughput of the system can be sought in a single optimisation run. The successful application of this methodology in a real-world automotive factory will also be addressed in this paper.

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    Optimal Maintenance Resources Allocation Using Automated Simulation-based Optimisation and Data Management
  • 166.
    Nikolakis, Nikolaos
    et al.
    Laboratory for Manufacturing Systems and Automation, Department of Mechanical Engineering and Aeronautics, University of Patras, Greece.
    Senington, Richard
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningsmiljön Virtuell produkt- och produktionsutveckling.
    Sipsas, Konstantinos
    Laboratory for Manufacturing Systems and Automation, Department of Mechanical Engineering and Aeronautics, University of Patras, Greece.
    Syberfeldt, Anna
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningsmiljön Virtuell produkt- och produktionsutveckling.
    Makris, Sotiris
    Laboratory for Manufacturing Systems and Automation, Department of Mechanical Engineering and Aeronautics, University of Patras, Greece.
    On a containerized approach for the dynamic planning and control of a cyber - physical production system2020Ingår i: Robotics and Computer-Integrated Manufacturing, ISSN 0736-5845, E-ISSN 1879-2537, Vol. 64, artikel-id 101919Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The increased complexity of modern production systems requires sophisticated system control approaches to maintain high levels of flexibility. Furthermore, the request for customized production with the introduction of heterogeneous production resources, increases the diversity of manufacturing systems making their reconfiguration complex and time consuming. In this paper, an end-to-end approach for reconfigurable cyber-physical production systems is discussed, enabled by container technologies. The presented approach enhances flexibility in a cyber-physical production system (CPPS) through the dynamic reconfiguration of the automation system and the production schedule, based on occurring events. High-level management of manufacturing operations is performed on a centralized node while the data processing and execution control is handled at the network edge. Runtime events are generated at the edge and in smart connected devices via means of a variant of IEC61499 function blocks. Software containers manage the deployment and low-level orchestration of FBs at the edge devices. All aspects of the proposed solution have been implemented on a software framework and applied in a small scale CPPS coming from the automotive industry.

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  • 167.
    Nilsson, Amanda
    et al.
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap.
    Lindqvist, Hanna
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap.
    Framtidens produktionspersonal i den Smarta fabriken2016Självständigt arbete på grundnivå (kandidatexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    The project has explored the topic Smart factory with main focus on the future production staff. The project aims to investigate how the production staff is affected by Volvo Cars Skövde Engine Plant (SkEP) becoming a Smart factory, in the era of Industry 4.0. The definition of the Smart factory is a demand of Mobile- and wireless technologies, Human-oriented, pursue a Flexible production with Sustainable manufacturing, as well as utilization of CPS (Cyber-Physical Systems), IoT (Internet-of-Things) and Cloud storage. The current situation and the future five to twenty years were examined in order to define the future production staff. This by conducting an observational study and several interviews. The studies’ results were that SkEP cannot be regarded as smart since several demands are inadequate by definition. Five years are considered too short of a time for the plant to fulfill the demands. However, according to the interviews and literature, SkEP are expected to become smart in twenty years after time refinement of existing technologies and implementation of new ones. The authors estimate Leadership, Information, IT and Production lay-out to be the areas that require the most effort. The future production staff are expected to be flexible with workplace, working hours and able to manage multiple variants. They should be included in self-supporting teams where every individual possesses an expertise, are motivated and participating. Production staff should perform complex, varied jobs with more responsibility by endorsement of decision support systems. The staffs’ competence should consist of technical education, high basic and lay-out knowledge and the ability to contribute to the collection of information and analyses. Interaction with technology is expected to expand and the personnel must therefore have a well-established comprehension of technology. The concept Smart factory is extensive and relatively new, which means that it is constantly evolving. Thus it is important for SkEP to be updated and adjust to the impact from the outside world.

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  • 168.
    Nilsson, Jesper
    et al.
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap.
    Shamoun, Steven
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap.
    Decision Support for new Process Design via Discrete-event Simulation2019Självständigt arbete på grundnivå (kandidatexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    As a result of the technical breakthrough of modern age, manufacturing organisations are put through immense pressure to continually improve their internal processes with the purpose of economic growth in order to stay competitive in the global market. Thus, making trial and error obsolete in the real world systems, in relation to calculated decision making. This thesis aims to facilitate the decision making basis for the partner companies’ future production design by measuring its expected productivity with the purpose to further strengthen the collaboration with the customer, by the use of discrete-event simulation.AB Furhoffs Rostfria is a family-owned company with its base in Skövde that manufactures and pro-cesses stainless steel products and specialises in three central departments, plumbing, kitchen, and subcontracting products. This thesis focus is within the production of heat shields in the department of subcontracting products as they are projecting an annual increase of 20%.The project was initialised with a pre-study phase that includes the theoretical framework, covering all main subjects to be presented along with analysing relevant literature studies for valuable insight into previous studies within the same field. Following a method and execution phase was carried out coher-ently with creating a simulation model and data collection. Different scenarios in the simulation model have been presented to the partner company along with wastes that have been observed within the production flow during Gemba.The different scenarios in the simulation model included, for instance, the production of both bigger and smaller batch sizes for each variant to analyse how that factor correlates with the product lead time and to also find out what the most optimal batch sizes would be for the respective variant in order to build full pallets. The future state production was evaluated and the results reduced the mean lead time by roughly 59% compared to the current state production.

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  • 169.
    Nord, Jens
    et al.
    Högskolan i Skövde, Institutionen för teknik och samhälle.
    Johansson, Peter
    Högskolan i Skövde, Institutionen för teknik och samhälle.
    Vägen till Lean Production: Historien bakom Lean och dess nutida användning2007Självständigt arbete på grundnivå (kandidatexamen), 20 poäng / 30 hpStudentuppsats
    Abstract [sv]

    I dagens samhälle ställs hårda krav på resultatförbättringar i företag och industrier. Det är vanligt att företag tar hjälp av någon eller några av de ledningsverktyg som finns utvecklade i just detta syfte, Lean Production är ett av dessa verktyg. Syftet med denna rapport är att ge en historisk bakgrund till Lean Production och att undersöka vilka tillvägagångssätt tre företag har valt för att implementera Lean i sin verksamhet. Vidare skall författarna undersöka om det finns några likheter mellan dessa tillvägagångssätt och Toyotas produktionssystem (TPS).

    Utvecklingen till det som idag benämns som Lean började redan 1911 då Fredrick Winslow Taylor presenterade sin artikel ”Principles of Scientific Management”. Henry Ford anammade Taylors idéer i sin nybyggda bilfabrik i Detroit år 1912 och utvecklade Fordismen, Ford blev sinnesbilden för rationell tillverkning. Under 1930-talet hade en annan biltillverkare, japanska Toyota, mycket stora svårigheter och hade svårt att överleva den västerländska konkurrensen. Företaget blev tvunget att genomföra radikala förändringar och påbörjade därför 1950 utvecklingen av sitt produktionssystem, TPS. Produktionssystemet, som byggdes runt fjorton principer, skulle visa sig få ett stort genomslag efter oljekrisen 1973. Amerikanerna började intressera sig för TPS och utifrån detta system utvecklades under 1980-talet det vi idag kallar Lean Production.

    De i studien undersökta verksamheterna, två av AstraZenecas fabriker samt Volvo Powertrains fabrik för kamaxlar presenterar olika tillvägagångssätt att arbeta med konceptet. Empirin har samlats in genom personliga och öppna intervjuer med personer som är väl insatta i verksamheternas förbättringsarbete. Den första fallstudien visar på ett mjukt tillvägagångssätt med mer fokus på företagskultur och på medarbetare än ren användning av verktyg. Den andra fallstudien visar på att fabriken valt verktygen framför medarbetarnas medbestämmande och bemyndigande. Det tredje fallstudieföretaget har arbetat med förbättringar en längre tid och har därför lyckats implementera både mjuka och hårda delar i verksamheten.

    För att lyckas med Lean och få konceptet att bli ett sätt att vara mer än enbart en uppsättning verktyg krävs att verksamheten på sikt implementerar såväl konceptets hårda som mjuka delar. Med hårda delar menas här resultatinriktade verktyg, medan de mjuka delarna fokuserar mer på medarbetarnas bemyndigande, självkänsla och medvetenhet. Fallstudierna visar tydligt att Toyotas fjorton principer inte är framtagna och finns av en ren slump. För att långsiktigt lyckas med Lean är det ett måste att alla principer återfinns i företagets arbetssätt. Finns inte alla principer med finns det en stor risk för att konceptet förblir en uppsättning verktyg som förbättrar företagets processer och försvinner inom ett antal år. En långsiktighet och kontinuitet måste finnas i arbetet och en alltför stor fokusering på kortsiktiga ekonomiska vinningar och korta ekonomiska mål är således inget att rekommendera för företag som vill att Lean skall efterlevas.

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  • 170.
    Nourmohammadi, Amir
    et al.
    Faculty of Industrial & Systems Engineering, Tarbiat Modares University, Tehran, Iran.
    Eskandari, Hamidreza
    Iran Management & Technology Development Center, Tarbiat Modares University, Tehran, Iran.
    Fathi, Masood
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningscentrum för Virtuella system.
    Design of stochastic assembly lines considering line balancing and part feeding with supermarkets2019Ingår i: Engineering optimization (Print), ISSN 0305-215X, E-ISSN 1029-0273, Vol. 51, nr 1, s. 63-83Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This article aims to address the assembly line balancing problem (ALBP) and supermarket location problem (SLP) as two long-term interrelated decision problems considering the stochastic nature of the task times and demands. These problems arise in real-world assembly lines during the strategic decision-making phase of configuring new assembly lines from both line balancing and part-feeding (PF) aspects. A hierarchical mathematical programming model is developed, in which the first level resolves the stochastic ALBP by minimizing the workstation numbers and the second level deals with the stochastic SLP while optimizing the PF shipment, inventory and installation costs. The results of case data from an automotive parts manufacturer and a set of standard test problems verified that the proposed model can optimize the configuration of assembly lines considering both ALBP and SLP performance measures. This study also validates the effect of the stochastic ALBP on the resulting SLP solutions.

  • 171.
    Nourmohammadi, Amir
    et al.
    Tarbiat Modares University, Tehran, Iran.
    Eskandari, Hamidreza
    Tarbiat Modares University, Tehran, Iran.
    Fathi, Masood
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningscentrum för Virtuella system.
    Aghdasi, Mohammad
    Tarbiat Modares University, Tehran, Iran.
    A mathematical model for supermarket location problem with stochastic station demands2018Ingår i: Procedia CIRP, ISSN 2212-8271, E-ISSN 2212-8271, Vol. 72, s. 6s. 444-449Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This paper aims to investigate the effect of station demands variations on supermarket location problem (SLP). This problem arises in the real-world assembly line part feeding (PF) context where supermarkets are used as the intermediate storage areas for stations. To this purpose a stochastic SLP model is developed to optimize the total cost of PF in terms of shipment, inventory and installation costs. The computational results over a real case as well as different test instances verify that the station demands variation has an effect on the SLP solutions.

  • 172.
    Nourmohammadi, Amir
    et al.
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningscentrum för Virtuella system. Faculty of Industrial & Systems Engineering, Tarbiat Modares University, Tehran, Iran.
    Eskandari, Hamidreza
    Faculty of Management and Economics, Tarbiat Modares University, Tehran, Iran / School of Management, Swansea University, UK.
    Fathi, Masood
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningscentrum för Virtuella system.
    Ng, Amos H. C.
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningscentrum för Virtuella system.
    Integrated locating in-house logistics areas and transport vehicles selection problem in assembly lines2019Ingår i: International Journal of Production Research, ISSN 0020-7543, E-ISSN 1366-588XArtikel i tidskrift (Refereegranskat)
    Abstract [en]

    Decentralised in-house logistics areas, known as supermarkets, are widely used in the manufacturing industry for parts feeding to assembly lines. In contrary to the literature and inspired by observation in a real case, this study relaxes the assumption of using identical transport vehicles when deciding on the supermarkets’ location by considering the availability of different vehicles. In this regard, this study deals with the integrated supermarket location and transport vehicles selection problems (SLTVSP). A mixed-integer programming (MIP) model of the problem is developed. Due to the complexity of the problem, a hybrid genetic algorithm (GA) with variable neighborhood search (GA-VNS) is also proposed to address large-sized problems. The performance of GA-VNS is compared against the MIP, the basic GA, and simulated annealing (SA) algorithm. The computational results from the real case and a set of generated test problems show that GA-VNS provides a very good approximation of the MIP solutions at a much shorter computational time while outperforming the other compared algorithms. The analysis of the results reveals that it is beneficial to apply different transport vehicles rather than identical vehicles for SLTVSP.

  • 173.
    Nourmohammadi, Amir
    et al.
    Tarbiat Modares University, Tehran, Iran.
    Eskandari, Hamidreza
    Tarbiat Modares University, Tehran, Iran.
    Fathi, Masood
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningscentrum för Virtuella system.
    Ranjbar Bourani, Mehdi
    University of Science & Technology of Mazandaran, Behshahr, Iran.
    An integrated model for cost-oriented assembly line balancing and parts feeding with supermarkets2018Ingår i: Procedia CIRP, ISSN 2212-8271, E-ISSN 2212-8271, Vol. 72, s. 5s. 381-385Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This paper aims to deal with assembly line design from both line balancing and parts feeding (PF) aspects as two-interrelated decision problems while supermarkets are used. These problems arise in the real-world assembly lines (ALs) where decision makers are planning to simultaneously determine the optimal number of stations and the optimal number of supermarkets so that the total installation costs of ALs including line balancing and PF costs are minimized. To this purpose an integrated mathematical model is proposed and its performance is tested through solving a number of benchmark problems and a real case taken from industry.

  • 174.
    Nourmohammadi, Amir
    et al.
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningscentrum för Virtuella system.
    Fathi, Masood
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningscentrum för Virtuella system.
    Ng, Amos H. C.
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningscentrum för Virtuella system.
    Choosing efficient meta-heuristics to solve the assembly line balancing problem: A landscape analysis approach2019Ingår i: Procedia CIRP, ISSN 2212-8271, E-ISSN 2212-8271, Vol. 81, s. 1248-1253Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    It is widely known that the assembly line balancing problem (ALBP) is an NP-hard optimization problem. Although different meta-heuristics have been proposed for solving this problem so far, there is no convincing support that what type of algorithms can perform more efficiently than the others. Thus, using some statistical measures, the landscape of the simple ALBP is studied for the first time in the literature. The results indicate a flat landscape for the problem where the local optima are uniformly scattered over the search space. Accordingly, the efficiency of population-based algorithms in addressing the considered problem is statistically validated.

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  • 175.
    Nourmohammadi, Amir
    et al.
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningscentrum för Virtuella system.
    Fathi, Masood
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningscentrum för Virtuella system.
    Ruiz Zúñiga, Enrique
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningscentrum för Virtuella system.
    Ng, Amos H. C.
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningscentrum för Virtuella system.
    A Genetic Algorithm for Bi-Objective Assembly Line Balancing Problem2019Ingår i: Advances in Manufacturing Technology XXXIII: Proceedings of the 17th International Conference on Manufacturing Research, incorporating the 34th National Conference on Manufacturing Research, September 10–12, 2019, Queen’s University Belfast, UK / [ed] Yan Jin, Mark Price, Amsterdam: IOS Press, 2019, Vol. 9, s. 519-524Konferensbidrag (Refereegranskat)
    Abstract [en]

    Assembly line designs in manufacturing commonly face the key problem of dividing the assembly tasks among the working stations so that the efficiency of the line is optimized. This problem is known as the assembly line balancing problem which is known to be NP-hard. This study, proposes a bi-objective genetic algorithm to cope with the assembly line balancing problem where the considered objectives are the utilization of the assembly line and the workload smoothness measured as the line efficiency and the variation of workload, respectively. The performance of the proposed genetic algorithm is tested through solving a set of standard problems existing in the literature. The computational results show that the genetic algorithm is promising in providing good solutions to the assembly line balancing problem.

  • 176.
    Nourmohammadi, Amir
    et al.
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningscentrum för Virtuella system.
    Fathi, Masood
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningscentrum för Virtuella system.
    Zandieh, Mostafa
    Department of Industrial Management, Management and Accounting Faculty, SBU, G.C., Tehran, Iran.
    Ghobakhloo, Morteza
    Department of Industrial Engineering, Minab Higher Education Center, University of Hormozgan, Bandar Abbas, Iran / Modern Technology Development and Implementation Research Center, University of Hormozgan, Bandar Abbas, Iran.
    A water-flow like algorithm for solving U-shaped assembly line balancing problems2019Ingår i: IEEE Access, E-ISSN 2169-3536, Vol. 7, s. 129824-129833Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The problem of assigning assembly tasks to the stations arranged along a material handling device is known as assembly line balancing. This paper aims to address the U-shaped assembly line balancing problem (UALBP) which arises when a U-shaped assembly line has to be configured. It is widely known that this problem is NP-hard. Accordingly, different meta-heuristics based on a single solution (such as Simulated Annealing) or a population of solutions (such as Genetic Algorithms) have been proposed in the literature. Meanwhile, it has been argued that either of these meta-heuristics with a fixed number of solutions cannot maintain efficient search progress and thus can lead to premature convergence. Thus, this study aims at adopting a novel meta-heuristic algorithm with dynamic population sizes, namely Water Flow-like Algorithm (WFA), inspired by the behaviour of water flows in nature, to address the UALBP. The line efficiency and variation of workload are considered as the primary and the secondary objective, to be optimized, respectively. To verify the efficiency and robustness of the proposed WFA, a real case study taken from an automobile manufacturer as well as a set of standard problems are solved and the results compared with the existing approaches in the literature. The computational results demonstrate the superiority of the WFA, particularly in addressing medium to large-sized problems.

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  • 177.
    Ohlander, Ulrika
    et al.
    Högskolan i Skövde, Institutionen för informationsteknologi. Högskolan i Skövde, Forskningscentrum för Informationsteknologi. Saab AB, Saab Aeronautics, Linköping, Sweden.
    Alfredson, Jens
    Saab AB, Saab Aeronautics, Linköping, Sweden.
    Riveiro, Maria
    Högskolan i Skövde, Institutionen för informationsteknologi. Högskolan i Skövde, Forskningscentrum för Informationsteknologi.
    Falkman, Göran
    Högskolan i Skövde, Institutionen för informationsteknologi. Högskolan i Skövde, Forskningscentrum för Informationsteknologi.
    Fighter pilots' teamwork: a descriptive study2019Ingår i: Ergonomics, ISSN 0014-0139, E-ISSN 1366-5847, Vol. 62, nr 7, s. 880-890Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The execution of teamwork varies widely depending on the domain and task in question. Despite the considerable diversity of teams and their operation, researchers tend to aim for unified theories and models regardless of field. However, we argue that there is a need for translation and adaptation of the theoretical models to each specific domain. To this end, a case study was carried out on fighter pilots and it was investigated how teamwork is performed in this specialised and challenging environment, with a specific focus on the dependence on technology for these teams. The collaboration between the fighter pilots is described and analysed using a generic theoretical model for effective teamwork from the literature. The results show that domain-specific application and modification is needed in order for the model to capture fighter pilot's teamwork. The study provides deeper understanding of the working conditions for teams of pilots and gives design implications for how tactical support systems can enhance teamwork in the domain. Practitioner summary: This article presents a qualitative interview study with fighter pilots based on a generic theoretical teamwork model applied to the fighter domain. The purpose is to understand the conditions under which teams of fighter pilots work and to provide guidance for the design of future technological aids.

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  • 178.
    Ore, Fredrik
    et al.
    Mälardalen University, Eskilstuna / Scania CV AB, Södertälje.
    Hanson, Lars
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningscentrum för Virtuella system. Chalmers University of Technology / Scania CV AB, Södertälje.
    Delfs, Niclas
    Fraunhofer-Chalmers Centre, Göteborg.
    Wiktorsson, Magnus
    Mälardalen University, Eskilstuna.
    Human Industrial Robot Collaboration – development and application of simulation software2015Ingår i: International Journal of Human Factors Modelling and Simulation, ISSN 1742-5557, Vol. 5, nr 2, s. 164-185Artikel, forskningsöversikt (Refereegranskat)
    Abstract [en]

    Human industrial robot collaboration (HIRC) aims to combine the benefits of industrial robots with humans in production environments. This is a growing research field where most work focuses on the safety aspects, while little research is performed on simulation and visualisation. The aim of this paper is to present a demonstrator software for simulation, visualisation and evaluation of human industrial robot collaboration.

    Two simulation software products were combined to reach this goal. The new tool was then applied to two industrial assembly cases where productivity and biomechanical loads on humans were calculated. The resulting demonstrator software simulates and visualises human industrial robot collaboration. The quantitative output from the simulation makes it possible to compare HIRC, manual and robotic assembly stations in terms of productivity and ergonomics.

  • 179.
    Ore, Fredrik
    et al.
    School of Innovation, Design and Engineering, Mälardalen University, Eskilstuna / Scania CV AB, Global Industrial Development, Södertälje, Sweden.
    Vemula, Bhanoday
    School of Innovation, Design and Engineering, Mälardalen University, Eskilstuna.
    Hanson, Lars
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningscentrum för Virtuella system. Scania CV AB, Global Industrial Development, Södertälje / Department of Industrial and Materials Science, Chalmers University of Technology, Göteborg.
    Wiktorsson, Magnus
    School of Innovation, Design and Engineering, Mälardalen University, Eskilstuna.
    Fagerström, Björn
    School of Innovation, Design and Engineering, Mälardalen University, Eskilstuna.
    Simulation methodology for performance and safety evaluationof human–industrial robot collaboration workstation design2019Ingår i: International Journal of Intelligent Robotics and Applications, ISSN 2366-5971, Vol. 3, nr 3, s. 269-282Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    There is a strong interest in the scope of human–industrial robot collaboration (HIRC) in manufacturing industry for greater flexibility and productivity. However, HIRC in manufacturing is still in its infancy; industrial practitioners have many apprehensions and uncertainties concerning the system’s performance and human operators’ safety. Therefore, there is a need for investigations into design processes and methods to make sure the designed HIRC workstations successfully meet design guidelines on system performance, human safety and ergonomics for practical industrial applications. This research proposes a HIRC workstation design process. The novelty of this design process is the methodology to evaluate the HIRC workstation design alternatives by considering both performance and safety characteristics through computer-based simulations. As a proof of concept, the proposed HIRC design process is applied on an industrial manufacturing case from a heavy-vehicle manufacturing company.

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  • 180.
    Ore, Fredrik
    et al.
    Mälardalen University, School of Innovation, Design and Engineering, Eskilstuna, Sweden / Scania CV AB, Global Industrial Development, Södertälje, Sweden.
    Vemula, Bhanoday Reddy
    Mälardalen University, School of Innovation, Design and Engineering, Eskilstuna, Sweden.
    Hanson, Lars
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningscentrum för Virtuella system. Scania CV AB, Global Industrial Development, Södertälje, Sweden / Chalmers University of Technology, Product and Production Development, Göteborg, Sweden.
    Wiktorsson, Magnus
    Mälardalen University, School of Innovation, Design and Engineering, Eskilstuna, Sweden.
    Human - Industrial Robot Collaboration: Application of simulation software for workstation optimisation2016Ingår i: 6th CIRP Conference on Assembly Technologies and Systems (CATS) / [ed] Rikard Söderberg, Elsevier, 2016, Vol. 44, s. 181-186Konferensbidrag (Refereegranskat)
    Abstract [en]

    The simulation possibilities of Human Industrial Robot Collaboration (HIRC) are limited in commercial software and published research. In order to meet this a demonstrator software has been developed. This paper presents the combination of the quantitative output from the software (measuring operation time and biomechanical load) together with existing optimisation techniques used to design the optimal HIRC workstation. An industrial case is used as an example where the optimal geometric handover position between robot and human is found. From the simulation software metamodels were created in order to represent the investigated workstation. The model was used in a multi-objective optimisation problem and resulted in a trade-off chart between operation time and biomechanical load. The result shows one example of the possibilities to combine the quantitative results from the simulation with optimisation in order to get the best solution to a HIRC design problem. (C) 2016 The Authors. Published by Elsevier B.V.

  • 181.
    Oscarsson, Jan
    et al.
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningscentrum för Virtuella system.
    Jeusfeld, Manfred A.
    Högskolan i Skövde, Institutionen för informationsteknologi. Högskolan i Skövde, Forskningscentrum för Informationsteknologi.
    Jenefeldt, Anders
    Volvo Cars Corporation, Skövde, Sweden.
    Towards Virtual Confidence - Extended Product Lifecycle Management2016Ingår i: Product Lifecycle Management in the Era of Internet of Things: 12th IFIP WG 5.1 International Conference, PLM 2015, Doha, Qatar, October 19-21, 2015, Revised Selected Papers / [ed] Abdelaziz Bouras, Benoit Eynard, Sebti Foufou & Klaus-Dieter Thoben, Springer, 2016, Vol. 467, s. 708-717Kapitel i bok, del av antologi (Refereegranskat)
    Abstract [en]

    Product lifecycle management (PLM) systems maintain amongst others the specifications and designs of product, process and resource artefacts and thus serve as the basis for realizing the concept of Virtual Manufacturing, and play a vital role in shortening the leadtimes for the engineering processes. Design of new products requires numerous experiments and test-runs of new facilities that delays the product release and causes high costs if performed in the real world. Virtualization promises to reduce these costs by simulating the reality. However, the results of the simulation must predict the real results to be useful. This is called virtual confidence. We propose a knowledge base approach to capture and maintain the virtual confidence in simulation results. To do so, the provenance of results of real, experimental and simulated processes are recorded and linked via confirmation objects.

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  • 182.
    Palmqvist, Erik
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap.
    Kartläggning och förbättringar av värdeflöden genom värdeflödesanalys: En empirisk fallstudie2014Självständigt arbete på grundnivå (kandidatexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    På Kongsberg Automotive (KA) i Mullsjö tillverkas bland annat växelföringssystem till en gemensam plattform av personbilar. Företaget ser idag potential i att förbättra flödet av produkterna och dess ingående komponenter genom fabriken. KA tillverkar dessutom många av komponenterna i samma fabrik som slutmonteringen sker vilket skapar goda förutsättningar till att upprätthålla effektiva flöden. Idag körs treskift i produktionen samt extra helgskift vid behov. Ett av målen med studien är att utreda möjligheterna till ett kontinuerligt treskift och eliminera extrainsatta helgskift då dessa är kostsamma för företaget. Syftet med studien är att kartlägga flödet för två av de ingående komponenterna i slutprodukten med hjälp av metoden värdeflödesanalys (VSM) och utifrån detta läge sedan skapa ett önskvärt framtida tillstånd där olika slöserier i flödet eliminerats. Målet är slutligen att upprätta en konkret handlingsplan för hur det framtida önskvärda tillståndet ska uppnås. Studien avser även att pröva huruvida metoden produktionssimulering kan användas som komplement till värdeflödesanalys för att kvantifiera identifierade förbättringar.

    Som ett första steg i studien behövde data samlas in för att kunna fastställa nuläget. Detta utfördes med olika metoder för att skapa en så bred och korrekt bild av verkligheten som möjligt. Dels genomfördes tidsstudier för att kartlägga eller verifiera redan given data. Även genomgång av olika dokument, leveranslistor och uppföljningslistor ligger till grund för det nuläge som tagits fram. Projektet har genomsyrats av en nära kontakt med personalen på företaget för att få fram så mycket och trovärdig information som möjligt. Deltagande observationer har skett löpande under studien för att få tillgång till förstahandsdata. Med hjälp av värdeflödesanalys har först ett nuläge och sedan ett önskvärt framtida läge kunnat fastslås. Som en del av projektet har även en produktionssimuleringsmodell skapats över det aktuella flödet i syfte att testa hypotesen att föreslagna förbättringar med hjälp av simulering kan stärkas och kvantifieras. Under arbetet med att skapa det framtida önskvärda läget genomfördes en workshop på företaget där personer med olika funktioner på olika avdelningar deltog. De förbättringsförslag som kunnat identifieras under arbetets gång och som ligger till grund för det framtida tillståndet resulterade slutligen i en konkret handlingsplan.

    Resultaten av studien visar på stor förbättringspotential i de kartlagda flödena. De teoretiska beräkningar som gjorts visar att ledtiderna för komponenterna kan reduceras med upp till 2/3 och att antalet produkter i arbete kan reduceras med upp till 50 %. Även en stor potential till förbättring av tillgängligheten i flaskhalsen har identifierats. Skulle tillgängligheten öka med omkring 9 % skulle också ett kontinuerligt treskift kunna tillämpas med nuvarande kundbehov. Studien har även resulterat i en slutsats om att produktionssimulering inte lämpar sig som metod i denna fallstudie. Istället har analyser och experiment kunnat utföras med mindre avancerade analytiska verktyg. Studien föreslår även att företaget investerar i utbildning då bristande kunskaper inom Lean production idag medför en begränsad förståelse för arbetet med att bli effektivare och mer flexibla.

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  • 183.
    Pehrsson, Leif
    Högskolan i Skövde, Forskningscentrum för Virtuella system. Högskolan i Skövde, Institutionen för teknik och samhälle.
    Manufacturing management and decision support using simulation-based multi-objective optimisation2013Doktorsavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    A majority of the established automotive manufacturers are under severe competitive pressure and their long term economic sustainability is threatened. In particular the transformation towards more CO2-efficient energy sources is a huge financial burden for an already investment capital intensive industry. In addition existing operations urgently need rapid improvement and even more critical is the development of highly productive, efficient and sustainable manufacturing solutions for new and updated products. Simultaneously, a number of severe drawbacks with current improvement methods for industrial production systems have been identified. In summary, variation is not considered sufficient with current analysis methods, tools used are insufficient for revealing enough knowledge to support decisions, procedures for finding optimal solutions are not considered, and information about bottlenecks is often required, but no accurate methods for the identification of bottlenecks are used in practice, because they do not normally generate any improvement actions. Current methods follow a trial-and-error pattern instead of a proactive approach. Decisions are often made directly on the basis of raw static historical data without an awareness of optimal alternatives and their effects. These issues could most likely lead to inadequate production solutions, low effectiveness, and high costs, resulting in poor competitiveness. In order to address the shortcomings of existing methods, a methodology and framework for manufacturing management decision support using simulation-based multi-objective optimisation is proposed. The framework incorporates modelling and the optimisation of production systems, costs, and sustainability. Decision support is created through the extraction of knowledge from optimised data. A novel method and algorithm for the detection of constraints and bottlenecks is proposed as part of the framework. This enables optimal improvement activities with ranking in order of importance can be sought. The new method can achieve a higher improvement rate, when applied to industrial improvement situations, compared to the well-established shifting bottleneck technique. A number of “laboratory” experiments and real-world industrial applications have been conducted in order to explore, develop, and verify the proposed framework. The identified gaps can be addressed with the proposed methodology. By using simulation-based methods, stochastic behaviour and variability is taken into account and knowledge for the creation of decision support is gathered through post-optimality analysis. Several conflicting objectives can be considered simultaneously through the application of multi-objective optimisation, while objectives related to running cost, investments and other sustainability parameters can be included through the use of the new cost and sustainability models introduced. Experiments and tests have been undertaken and have shown that the proposed framework can assist the creation of manufacturing management decision support and that such a methodology can contribute significantly to regaining profitability when applied within the automotive industry. It can be concluded that a proof-of-concept has been rigorously established for the application of the proposed framework on real-world industrial decision-making, in a manufacturing management context.

  • 184.
    Pehrsson, Leif
    et al.
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningscentrum för Virtuella system. Volvo Car Corporation, Gothenburg, Sweden.
    Lidberg, Simon
    Volvo Car Corporation, Gothenburg, Sweden.
    Frantzén, Marcus
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningscentrum för Virtuella system.
    Aslam, Tehseen
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningscentrum för Virtuella system.
    Ng, Amos
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningscentrum för Virtuella system.
    Aggregated Discrete Event Modelling for Simulation and Optimisation of Manufacturing Systems2014Ingår i: Industrial Simulation Conference, Skövde, June 11-13, 2014, Eurosis, 2014, 2014, s. 83-90Konferensbidrag (Refereegranskat)
    Abstract [en]

    In many simulation studies for factory analysis, for example, to locate the constraint of an entire factory that consists of multiple production lines, it may not be effective to put every process detail into a single model. Firstly, to develop such a factory-wide model would be very time-consuming. Secondly, it can be very computational costly to run the model, especially if simulation-based optimisation is applied to find the optimal setting from such a complex model that possesses all the details of the processes. In this regard, aggregation, with which multiple process steps are aggregated into some simpler simulation objects, is an effective method to reduce both the development and computational times. On one hand, based on the initial analysis, the simulation expert can pinpoint the sub-system that restrains the performance of the entire factory and decide if a more detailed model is needed. On the other hand, interline buffers/storages can be readily optimised by using such an aggregated model. Through an application study with data from a real-world factory, this paper introduces a novel aggregation method and illustrates the potential of the abovesaid concepts.

  • 185.
    Pehrsson, Leif
    et al.
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningscentrum för Virtuella system.
    Ng, Amos H. C.
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningscentrum för Virtuella system.
    Bernedixen, Jacob
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningscentrum för Virtuella system.
    Automatic identification of constraints and improvement actions in production systems using multi-objective optimization and post-optimality analysis2016Ingår i: Journal of manufacturing systems, ISSN 0278-6125, E-ISSN 1878-6642, Vol. 39, s. 24-37Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Manufacturing companies are operating in a severely competitive global market, which renders an urgent need for them to explore new methods to enhance the performance of their production systems in order to retain their competitiveness. Regarding the performance of a production system, it is not sufficient simply to detect which operations to improve, but it is imperative to pinpoint the right actions in the right order to avoid sub-optimizations and wastes in time and expense. Therefore, a more accurate and efficient method for supporting system improvement decisions is greatly needed in manufacturing systems management. Based on research in combining simulation-based multi-objective optimization and post-optimality analysis methods for production systems design and analysis, a novel method for the automatic identification of bottlenecks and improvement actions, so-called Simulation-based Constraint Identification (SCI), is proposed in this paper. The essence of the SCI method is the application of simulation-based multi-objective optimization with the conflicting objectives to maximize the throughput and minimize the number of required improvement actions simultaneously. By using post-optimality analysis to process the generated optimization dataset, the exact improvement actions needed to attain a certain level of performance of the production line are automatically put into a rank order. In other words, when compared to other existing approaches in bottleneck detection, the key novelty of combining multi-objective optimization and post-optimality analysis is to make SCI capable of accurately identifying a rank order for the required levels of improvement for a large number of system parameters which impede the performance of the entire system, in a single optimization run. At the same time, since SCI is basically built a top a simulation-based optimization approach, it is capable of handling large-scale, real-world system models with complicated process characteristics. Apart from introducing such a method, this paper provides some detailed validation results from applying SCI both in hypothetical examples that can easily be replicated as well as a complex, real-world industrial improvement project. The promising results compared to other existing bottleneck detection methods have demonstrated that SCI can provide valuable higher-level information to support confident decision-making in production systems improvement.

  • 186.
    Peralta Fernandez-Blanco, Antonio
    et al.
    Högskolan i Skövde, Institutionen för teknik och samhälle.
    Bellido Sanchez-Cañete,
    Högskolan i Skövde, Institutionen för teknik och samhälle.
    Development of a Portable Stable for Horses2009Självständigt arbete på grundnivå (kandidatexamen), 15 poäng / 22,5 hpStudentuppsats (Examensarbete)
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  • 187.
    Potros, Bashar
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap.
    Framställning av mätmetod för att upptäcka defekta luftmunstycken: Framställa en säker och tillförlitlig mätmetod för att mäta mängd vatten i 50 provrör2018Självständigt arbete på grundnivå (kandidatexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    För att upptäcka defekta luftmunstycken har Ecco Finishing AB i Skara tagit fram en ny provutrustning som ska ersätta en otillförlitlig och osäker befintlig provmaskin. Ecco Fi-nishing AB vill hitta en tillförlitlig och säker mätmetod som ska mäta mängd vatten i 50 provrör. Examensarbetets övergripande mål är att hitta en noggrann och repeterbar mätmetod för nivåmätning av vätska i provrören. Två mätmetoder utvärderades som är mest lämpliga för nivåmätningen, visionsystem och mätning genom vägning. Anledningen till att valet ham-nade på dessa två mätmetoder är provutrustningens provrör, dels att det är många mätpunkter och för att det är små provrör. Det gjordes tjugo experiment för visionsystem och tjugo ex-periment för vägningsmetod för att utvärdera och beskriva för - och nackdelar. Experimenten av visionsystem och vägning gjordes först i laborationsfas för att sedan testas på företagets befintliga provutrustning. Resultaten av mätningar sparades i ett Excel-ark som användes för att utvärdera insamlade data. Utvärderingarna jämfördes mot uppsatta mål, tillförlitlighet, noggrannhet, repeterbarhet, automatisk rapportering av resultat och tid för mätningen. Vis-ionsystem rekommenderas för fortsatt arbete och implementation på den befintliga provut-rustningen.

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  • 188.
    Quesada Díaz, Raquel
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap.
    Support component reusability by integrating augmented reality and product lifecycle management2016Självständigt arbete på avancerad nivå (magisterexamen), 15 poäng / 22,5 hpStudentuppsats (Examensarbete)
    Abstract [en]

    In an ever changing market that expands continuously and where innovations cycles become shorter, there is an important increase of the renewal frequency of the electrical and electronic equipment (EEE) and vehicles. This makes the manufacture of EEE and vehicles a fast-growing source of waste in terms of used products. The immense amount of information generated by all these technological products which are currently in the market must be managed throughout the whole life cycle of the products. The problem is to provide information about the technological product’s reusability in the recycling process given the colossal complexity of many products and the lifespan of operation. This includes instructions about the components qualifications as elements in a new product. Technologies such as augmented reality (AR) combined with product lifecycle management (PLM) systems can provide the platform for an information system that provides the necessary information and support for the decommissioning process of EEE and vehicles at the end of their life cycle.

    The present project describes the framework of integration between AR and PLM with the purpose of recycling a technological product at the end of its life cycle. The proposed method of integration could be considered to constitute both an innovation and a possible improvement if compared with the current approach. It is believed that the development of a method that addresses the issue of integration between AR and PLM could provide with a secure, efficient management of stored data related to various products and their properties related to the recycling process at the end-of-life of the product. The result of this approach is an AR-PLM system architecture which assists the circular economy’s recycling process by the use of visual information superimposed on the physical technological equipment.

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  • 189.
    Quesada Díaz, Raquel
    et al.
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningscentrum för Virtuella system.
    Syberfeldt, Anna
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningscentrum för Virtuella system.
    Product Disassembly and Inspection Supported by Augmented Reality and Product Lifecycle Management Integration2019Ingår i: Advances in Manufacturing Technology XXXIII: Proceedings of the 17th International Conference on Manufacturing Research, incorporating the 34th National Conference on Manufacturing Research, September 10–12, 2019, Queen’s University Belfast, UK / [ed] Yan Jin, Mark Price, Amsterdam: IOS Press, 2019, Vol. 9, s. 553-558Konferensbidrag (Refereegranskat)
    Abstract [en]

    Product disassembly and inspection are essential operations in a sustainable product life cycle, particularly in end-of-life strategies such as remanufacturing. This study describes the most frequent issues and outcomes that can be encountered during the implementation of a framework for the integration of technologies such as augmented reality, product identifiers and product lifecycle management in the context of disassembly and inspection. It is believed that the development of such framework could provide a secure, efficient management of stored data and a comprehensive support to the work process and the operators carrying out the disassembly and inspection.

  • 190.
    Rhén, Ida-Märta
    et al.
    Department of Industrial and Materials Science, Chalmers University of Technology.
    Forsman, Mikael
    IMM Institute of Environmental Medicine, Karolinska Institutet.
    Örtengren, Roland
    Department of Industrial and Materials Science, Chalmers University of Technology.
    Högberg, Dan
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningscentrum för Virtuella system.
    Keyvani, Ali
    Robotics and Automation, Virtual Manufacturing AB, Göteborg.
    Lämkull, Dan
    Global Strategy and Process Development, Volvo Car Corporation, Manufacturing Engineering, Göteborg.
    Hanson, Lars
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningscentrum för Virtuella system. Industrial Development, Scania CV, Södertälje / Department of Industrial and Materials Science, Chalmers University of Technology.
    Ergonomic risk assessment in DHM tools employing motion data: Exposure calculation and comparison to epidemiological reference data2018Ingår i: International Journal of Human Factors Modelling and Simulation, ISSN 1742-5549, Vol. 6, nr 1, s. 31-64Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Digital human modelling (DHM) allows ergonomic risk assessment to be performed at early stages of design and development. Such assessment is typically based on observational methods, which do not take advantage of the potential of DHM tools to provide precise posture and motion data. This paper describes and illustrates an alternative assessment approach employing DHM tools, inspired by risk assessment based on direct measurements. A literature survey established a reference database of epidemiological associations between exposure and wrist-related disorders. This approach is illustrated by a DHM simulation of a car assembly task. Wrist posture and motion were simulated and compared to the database, predicting the prevalence of work-related musculoskeletal disorders on the basis of direct measurements.

  • 191.
    Ruiz Castro, Pamela
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. student.
    Seating Comfort Analysis for Virtual Driver Research2015Självständigt arbete på grundnivå (kandidatexamen), 15 poäng / 22,5 hpStudentuppsats (Examensarbete)
    Abstract [en]

    There has been a rapid growth in the vehicle industry market, companies are expected to provide comfortable and safer products, improving with every new model. Hence, the interest on developing Digital Human Modelling (DHM) tools that are focused on their needs.

    The aim of this project is to suggest a standard seating posture that could be used with ergonomic software like IMMA, to address the research an initial literature study was performed to understand existing methods used in the industry and previous posture studies.

    In order to visualize the extent of the topic, it was required to acquire information from the vehicle industries and make an investigation on preferred postures by real drivers.

    Comparisons are made between the different categories of observed vehicles, and literature found for ideal postures. The results were also used to implement suggestions for the ergonomic IMMA software development

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  • 192.
    Ruiz Castro, Pamela
    et al.
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningscentrum för Virtuella system.
    Högberg, Dan
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningscentrum för Virtuella system.
    Ramsen, Håkan
    Volvo Trucks, Gothenburg, Sweden.
    Bjursten, Jenny
    Volvo Trucks, Gothenburg, Sweden.
    Hanson, Lars
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningscentrum för Virtuella system. Industrial Development, Scania, Södertälje, Sweden.
    Virtual Simulation of Human-Robot Collaboration Workstations2019Ingår i: Proceedings of the 20th Congress of the International Ergonomics Association (IEA 2018): Volume V: Human Simulation and Virtual Environments, Work With Computing Systems (WWCS), Process Control / [ed] Sebastiano Bagnara, Riccardo Tartaglia, Sara Albolino, Thomas Alexander, Yushi Fujita, Springer, 2019, Vol. 822, s. 250-261Konferensbidrag (Refereegranskat)
    Abstract [en]

    The constant call in manufacturing for higher quality, efficiency, flexibility and cost effective solutions has been supported by technology developments and revised legislations in the area of collaborative robots. This allows for new types of workstations in industry where robots and humans co-operate in performing tasks. In addition to safety, the design of such collaborative workstations needs to consider the areas of ergonomics and task allocation to ensure appropriate work conditions for the operators, while providing overall system efficiency. The aim of this study is to illustrate the development and use of an integrated robot simulation and digital human modelling (DHM) tool, which is aimed to be a tool for engineers to create and confirm successful collaborative workstations. An assembly scenario from the vehicle industry was selected for its redesign into a collaborative workstation. The existing scenario as well as potential collaborative concepts are simulated and assessed using a version of the simulation tool IPS IMMA. The assembly use case illustrates the capabilities of the tool to represent and evaluate collaborative workstations in terms of ergonomics and efficiency assessments.

  • 193.
    Ruiz-Amurrio, Maria
    et al.
    MGEP, Dept Mecan Prod & Ind, Arrasate Mondragon, Spain.
    Elorza, Unai
    MGEP, Dept Mecan Prod & Ind, Arrasate Mondragon, Spain.
    Linnéusson, Gary
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningscentrum för Virtuella system.
    Zabaleta-Etxebarria, Noemi
    MGEP, Dept Mecan Prod & Ind, Arrasate Mondragon, Spain.
    Identification of the factors which influence employee commitment using systems thinking = Identificación de factores que influyen en el compromiso de los empleados utilizando pensamiento sistemico2018Ingår i: DYNA, ISSN 0012-7361, Vol. 93, nr 5, s. 504-511Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In our increasingly globalised economy, managing continuous change and remaining competitive has become a central issue for organisations in the industrial sector. Building a sustainable competitive advantage through effective decision making and the use of decision making tools has been widely studied [1,2]. The success of a company will be dependent on the skills of the workers, their capacity for learning, and adapting to special and evolving client necessities. Culture change via, communication and participation are the elements of change identified for engineering companies [3]. Thus, the main objective of this research is to understand the behaviour of commitment, the variables that influence it and the variables that are influenced by it. Commitment is considered a key factor due to its influence on performance. The methodology that was followed was based on the modelling methodology proposed by Sterman [4]. The first step was the problem definition, the second step was data collection. The purpose was to define the feedback loops of which the conceptual model (CM) is composed. Thirdly, conceptual model definition was developed. As a result, the outcome that is achieved through this research is a conceptual model. The main function of this model is to facilitate the understanding of the behaviour of commitment through Systems Thinking tools. This research contributes to both Strategic Human Resource Management (SHRM) and Systems Thinking (ST) fields of study. The most notable contribution for ST is the fact of combining more than one input source (Literature + Group Model Building + prior research) for the conceptual model definition. The combination of these input sources for an ST model is not common in the scientific community. Moreover, the use of ST in SHRM is limited.

  • 194.
    Rösiö, Carin
    et al.
    Jönköping University School of Engineering, Department of Industrial Engineering and Management, Jönköping, Sweden.
    Aslam, Tehseen
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningscentrum för Virtuella system.
    Srikanth, Karthik Banavara
    Jönköping University School of Engineering, Department of Industrial Engineering and Management, Jönköping, Sweden.
    Shetty, Savin
    Jönköping University School of Engineering, Department of Industrial Engineering and Management, Jönköping, Sweden.
    Towards an assessment criterion of reconfigurable manufacturing systems within the automotive industry2019Ingår i: Procedia Manufacturing, E-ISSN 2351-9789, Vol. 28, s. 76-82Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    To increase changeability and reconfigurability of manufacturing systems, while maintaining cost-efficiency and environmental sustainability they need to be designed in accordance to the need for change. Since companies often need to convert existing manufacturing systems to handle variation, implementation of reconfigurable manufacturing systems calls for an analysis of the current system to understand to what extent they fulfil reconfigurability characteristics. This requires an assessment of the needs for reconfigurability as well as assessment of the existing ability to reconfigure the manufacturing system. Although a lot of reconfigurable manufacturing system assessment models are proposed in theory there is an evident knowledge gap pertaining to what extent the existing systems in the industry are in achieving reconfigurability. The purpose with this paper is to propose an assessment criterion for existing manufacturing systems to measure reconfigurability and their readiness to change with respect to products and volume variations. Based on a literature review of existing reconfigurability assessment models and a case study within the automotive industry, a criterion is developed and tested to analyze how reconfigurable a system is and to decide which parameters that need more attention to achieve higher degree of reconfigurability. © 2019 The Authors.

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  • 195.
    Saiegh, Gabi
    et al.
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap.
    Zaki, Alaa
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap.
    Intern logistik, industriella projekt med utvald processutrustning2016Självständigt arbete på grundnivå (yrkesexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    En förstudie av produktionen på ett företag gjordes med syfte att kartlägga produktionen på pastöriseringsavdelningen och därefter skapa ett förbättringsförslag. Målet med projektet är att arbeta fram två förbättringsförslag på åtgärder för att minska slöseriet på pastöriseringsavdelningen, ta fram en standard avseende arbetssättet i pastöriseringsavdelningen och jämföra det nya arbetssättet med det tidigare samt att ta fram ett förbättringsförslag avseende arbetssättet i orderhanteringen. Projektet är ett examensarbete på trettio högskolepoäng och skrivs på Högskolan i Skövde vårterminen 2016 för institutionen för ingenjörsvetenskap med inriktning automatisering och ledarskap. Författarna av denna rapport fick uppdraget från Dava foods i Skara. Projektet gjordes för att utveckla den befintliga produktionsprocessen. En värdeflödesanalys genomfördes för att se hur mycket tid av produktionen som utnyttjas. Det som störde produktionen var väntan som uppstod mellan de olika processerna i produktionskedjan. Enligt de teorier som studerades såsom Lean production är väntan ett slöseri. Med enkla metoder som tillämpning av dragande system, mellanlager till pacemaker-stationen och användningen av det föreslagna reservationsprogrammet skulle slöseriet kunna minskas. Effekten av detta skulle bli att operatören får mer tid att planera produktionen och att maskinerna kan utnyttjas bättre.

    Pastörerna är tillgängliga för produktionen under hela arbetstiden och för att använda den tiden maximalt krävs det standarder så att alla operatörer använder samma reservationsprogram. Resultatet blir ett jämnt och stabilt flöde samt en mer effektiv resursanvändning. Kravspecifikationerna i projektet har varit en bas för lösningar och förbättringsförslag. En pilotstudie utfördes för utvärderingsskedet.

    Detta projekt resulterade i ett förslag till en omorganisering i produktionsupplägget när det gäller orderhanteringen samt ett omstrukturerat mellanlager för att skapa ett kontinuerligt flöde genom en station som innebär en flaskhals för produktionen. Den nya Excelfil som skapades av författarna kan resultera i en tidsreducering och en minskad arbetsbörda för orderavdelningen. Denna lösning ska bidra till minskat tidsslöseri i form av onödiga rörelser. Ett förslag på tillämpning av 5S kan, om det implementeras, resultera i ökad ordning och reda på pastöriseringsavdelningen, en förutsättning för att stödja produktionens process.

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  • 196.
    Senington, Richard
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningscentrum för Virtuella system.
    Software containers as a generic foundation for iec 61499 distributed control systems2018Ingår i: Advances in Manufacturing Technology XXXII: Proceedings of the 16th International Conference on Manufacturing Research, incorporating the 33rd National Conference on Manufacturing Research, September 11–13, 2018, University of Skövde, Sweden / [ed] Peter Thorvald, Keith Case, Amsterdam: IOS Press, 2018, s. 273-278Konferensbidrag (Refereegranskat)
    Abstract [en]

    It is predicated that in the future factories will be more dependent upon complex distributed control software, where execution and communication occur at the edge of the system, close to the machines that are involved in the manufacturing process. This introduces the problem of how to effectively design, deploy and manage such systems. The IEC 61499 function block standard has been given as one way to solve this problem, proposing applications made from a number of modular event driven blocks that encapsulate algorithms potentially in any programming language. At the same time the Internet of Things and Cloud computing fields have encountered the similar problem of encapsulating, managing and distributing scalable applications, and have been investigating software containers as a solution. This paper proposes to combine these two approaches using containers to enable easy distribution and management of software modules on manufacturing devices while taking advantage of the IEC 61499 application model to enable an application orchestration tool. It describes the properties of container technology that can support the creation of function block like components and the proposal is supported by a prototype version of such a system which has already been implemented.

  • 197.
    Simonsson, Emma
    et al.
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap.
    Proszowski, Natlia
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap.
    Metod på ett nytt materialhanteringssätt2017Självständigt arbete på grundnivå (kandidatexamen), 15 poäng / 22,5 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Examensarbetet är utfört på AB Furhoffs Rostfria som är ett specialistföretag inom tillverkning och bearbetning av egenutvecklade produkter i rostfritt stål och tillverkar VVS-produkter, storkök, diskbänkar samt har en legotillverkning. Företaget arbetar ständigt med att effektivisera sin produktion samtidigt som nya produkter utvecklas. Därför har de satt igång ett projekt som ska leda till ökad produktion och omsättning utan att öka sin fabriksyta eller öka personalstyrkan. För att lyckas krävs det att den interna materialhanteringen blir effektivare.

     

    Syftet och huvudmålen var att ta fram en metod för ett nytt materialhanteringssätt samt utforma monteringsstationer med hänsyn till ergonomi, effektivitet och kvalitetssäkring. Utöver detta skulle en lämplig layout över VVS-monteringen formas. För att säkerställa att projektet skulle uppnå syftet och huvudmålen applicerades en PDCA-modell på examensarbetet. Relevanta teori- och litteraturstudier genomfördes för att ta fram rätt metoder för att samla in data.

     

    Efter ett utstuderat nuläge fastställdes att personalen frekvent letar, hämtar och plockar produkter samt emballering och packning av färdigställda produkter tog lång tid att utföra. Det resulterade i att personalen utförde mycket nödvändiga men icke-värdeskapande aktiviteter. Personalen använde inte heller sin arbetsplats på korrekt sätt utifrån ett ergonomiskt samt effektivt perspektiv. VVS-monteringens layout förde med sig fler nackdelar än fördelar.

     

    Det utformade förslaget är framtaget utifrån resultat av empiriska studier som sedan kopplats mot de teoretiska studierna. Ett layoutförslag har tagits fram som kan reducera onödiga transporter samt rörelser genom att placera monteringsplatser samt lager på ett strategiskt vis. Kittning medför många fördelar som effektiviserar och jämnar ut produktionsflödet och skapar en stabil produktion. En prototypskiss för en lämplig och effektiv kitt-vagn har tagits fram för företaget att fortsätta utveckla efter egna förutsättningar

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  • 198.
    Skoogh, Anders
    et al.
    Chalmers University of Technology, Gothenburg, Sweden.
    André, Jean-Patrick
    Chalmers University of Technology, Gothenburg, Sweden.
    Dudas, Catarina
    Högskolan i Skövde, Institutionen för teknik och samhälle. Högskolan i Skövde, Forskningscentrum för Virtuella system.
    Svensson, Jacob
    Högskolan i Skövde, Institutionen för teknik och samhälle. Högskolan i Skövde, Forskningscentrum för Virtuella system.
    Urenda Moris, Matias
    Högskolan i Skövde, Institutionen för teknik och samhälle. Högskolan i Skövde, Forskningscentrum för Virtuella system.
    Johansson, Björn
    Chalmers University of Technology, Gothenburg, Sweden.
    An automated approach to input data management in discrete event simulation projects: A proof-of-concept demonstrator2007Ingår i: EUROSIM 2007, 2007Konferensbidrag (Refereegranskat)
    Abstract [en]

    Despite the fact that Discrete Event Simulation (DES) is claimed to be one of the most potent tools for analysis and optimization of production systems, industries worldwide have not been able to fully utilize its potential. One reason is argued to be that DES projects are not time efficient enough due to extensive time consumption during the input data phases. In some companies, input data is totally missing, but even in projects where data is available it usually takes a considerable amount of time to analyze and prepare it for use in a simulation model. This paper presents one approach to the problem by implementing a software that automates several steps in the input data process such as extracting data from a database, sorting out the information needed and fitting the data to statistical distributions. The approach and the software have been developed based on a case study at Volvo Trucks in Gothenburg, Sweden. The work presented in this paper is part of a more comprehensive project called FACTS. The project scope is to develop methods and IT-tools for conceptual plant development. 

  • 199.
    Strand, Mattias
    et al.
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningsmiljön Virtuell produkt- och produktionsutveckling.
    Syberfeldt, Anna
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningsmiljön Virtuell produkt- och produktionsutveckling.
    Using external data in a BI solution to optimise waste management2020Ingår i: Journal of Decision Systems, ISSN 1246-0125, E-ISSN 2116-7052, Vol. 29, nr 1, s. 53-68Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    BI solutions are constantly being developed to support decision-making at various organisational levels. These solutions facilitate the compilation, aggregation and summarisation of large volumes of data. Consequently, the business value created by these systems is increasing as they sustain more and more advanced analytics, ranging from descriptive analytics, to predictive analytics, to prescriptive analytics. However, most organisations work primarily with internal data. Despite many references in the literature to the value hidden in external data, details on how such data can be used are scarce. In this paper, we present the results of an extensive action case study at a public waste management company. The results illustrate how external data from several external data sources, integrated into an up-and-running BI solution, are used jointly to allow for descriptive and predictive analytics, as well as prescriptive analytics. In addition, details of these analytical values are given and related to organisational benefits.

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  • 200.
    Sumbal, Muhammad Saleem
    et al.
    Department of Management and HR, NUST Business School, National University of Sciences and Technology (NUST), Islamabad, Pakistan.
    Tsui, Eric
    Department of Industrial and Systems Engineering, Hong Kong Polytechnic University, Kowloon, Hong Kong.
    Durst, Susanne
    Högskolan i Skövde, Institutionen för handel och företagande. Högskolan i Skövde, Forskningsmiljön Framtidens företagande.
    Shujahat, Muhammad
    Knowledge Management and E-Learning Lab, Faculty of Education, The University of Hong Kong, Hong Kong.
    Irfan, Irfan
    Department of Management and HR, NUST Business School, National University of Sciences and Technology (NUST), Islamabad, Pakistan.
    Ali, Syed Muhammad
    Department of Engineering Management, National University of Sciences and Technology (NUST), Islamabad, Pakistan.
    A framework to retain the knowledge of departing knowledge workers in the manufacturing industry2020Ingår i: VINE Journal of Information and Knowledge Management Systems, ISSN 2059-5891Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Purpose: The purpose of this study is to develop a conceptual framework on knowledge loss in a manufacturing sector based on three aspects: likelihood of knowledge loss, critical areas of knowledge loss and relevance of each of these knowledge areas in terms of utilization and alignment with organizational goals and strategy. Such a conceptual framework can be helpful to the practicing managers in understanding the types of knowledge that is lost of a given departing employee and thus deciding on a measure to retain the critical employees or capture their knowledge before they leave. Design/methodology/approach: Using a case study approach, data has been collected from a multinational battery manufacturing company based in Hong Kong. Semi-structured interviews have been conducted and analyzed through CAQDAS ATLAS.ti to generate the themes which were then used to develop the conceptual framework. Findings: The findings revealed that the likelihood factors of knowledge loss in the manufacturing sector include layoffs, retirement, immigration and job change. The critical areas of knowledge loss comprise the knowledge of relationships and networks, especially with the customers and suppliers, the technical knowledge (battery and process technology) and knowledge of management, among others. The relevance of each of these knowledge areas needs to be determined through proper analysis whether these knowledge areas are needed in future projects, up to date and aligned with organizational goals and strategy along with other factors. Research limitations/implications: Using the developed conceptual framework, managers and executives can identify critical employees in the manufacturing sector and accordingly take some appropriate measures to retain their knowledge. Caution should be taken while applying the findings of this study in other industries and context. Originality/value: This paper is an attempt to reduce the dearth of empirical studies by exploring knowledge retention in the manufacturing sector, especially in the development of proper conceptual frameworks to assess the potential knowledge loss of employees.

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