| 1. |
- Gustavsson, Patrik, 1988-
(författare)
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Virtual Reality Platform for Design and Evaluation of the Interaction in Human-Robot Collaborative Tasks in Assembly Manufacturing
- 2020
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Industry is on the threshold of the fourth industrial revolution where smart factories area necessity to meet customer demands for increasing volumes of individualized products. Within the smart factory, cyber-physical production systems are becoming important to deal with changing production. Human-robot collaboration is an example of a cyber-physical system in which humans and robots share a workspace. By introducing robots and humans into the same working cell, the two can collaborate by allowing the robot to deal with heavy lifting, repetitive, and high accuracy tasks, while the human focuses on tasks that need intelligence, flexibility, and adaptability. There are few such collaborative applications in industry today. In the implementations that actually exist, the robots are mainly working side-by-side with humans rather than truly collaborating. Three main factors that limit the widespread application of human-robot collaboration can be identified: lack of knowledge regarding suitable human-robot collaboration tasks, lack of knowledge regarding efficient communication technologies for enabling interaction between humans and robots when carrying out tasks, and lack of efficient ways to safely analyze and evaluate collaborative tasks.The overall aim of this thesis is to address these problems and facilitate and improve interaction between humans and robots, with a special focus on assembly manufacturing tasks. To fulfill this aim, an assembly workstation for human-robot collaboration has been developed and implemented both physically and virtually. A virtual reality platform called ViCoR has been developed that can be used to investigate, evaluate, and analyze the interaction between humans and robots and thereby facilitate the implementation of new human-robot collaboration cells. The workstation developed has also been used for data collection and experiments during the thesis work, and used to extract knowledge of how the interaction between human and robot can be improved.
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| 2. |
- Kurdve, Martin, et al.
(författare)
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Production System Change Strategy in Lightweight Manufacturing
- 2016
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Ingår i: Procedia CIRP. - : Elsevier BV. - 2212-8271. ; , s. 160-165
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Konferensbidrag (refereegranskat)abstract
- Two change management strategies: a minimum change, exploitation strategy (kaizen) and a maximum output, exploration strategy (kaikaku) have been applied in a manufacturing case study. Value stream mapping and discrete event simulation were used to analyse the production system changes, with regards to robustness and total lead-time, to increase knowledge of how to choose change management strategy. The results point out that available time is crucial. It is important to consider not only product specification and return of investment, but also the change and risk management. Future research should develop engineering change management further.
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| 3. |
- Abid, Muhammad, 1981-
(författare)
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Global Supply Chain Design : Exploring configurational and coordination factors
- 2015
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis addresses the topic of global supply chain design. One major challenge concerns how to manage the tension between separation and integration pertaining to the localization of business activities. In this regard Ferdows (2008) worked to create two new production network models (rooted production network and footloose production network). Earlier studies have highlighted the choices that are involved in the network of facilities but lack in providing a comprehensive picture in terms of both configurational and coordination factors that govern the design of global supply chain. There is a need for a conceptual model where factors affecting the design process of a global supply chain can be applied. Two main research questions have been addressed in this study. First, exploring and identifying the factors affecting global supply chain design. Second, investigating the factors that influence the position on the spectrum of rooted and footloose supply chain design. A literature review analysis and multi-case studies have been performed for this study in order to explore the factors. The companies were selected in order to reflect upon the two types of network, i.e., rooted and footloose. The primary data were selected through interviews with the managers.This study highlighted that there are many factors that affect configurational and coordination decision areas within a global supply chain. This study categorized the factors and the configurational/coordination decision areas with two main competitive priorities, i.e., cost and differentiation in the form of a “conceptual model.” The study also highlighted the factors in a matrix, which showed their position on the spectrum of rooted and footloose network configurations. For instance, the coordination factors that drive towards a footloose network include: high orchestration capabilities, need access to new technology and knowledge, proximity to suppliers, etc. The configurational factors that drive towards a rooted network include: economic stability, proximity to market, concerns for sustainability issues, high transportation cost, need for high proximity between key functions, need for intellectual property rights protection, etc.
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| 4. |
- Agrawal, Tarun Kumar, et al.
(författare)
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Blockchain-Based Secured Collaborative Model for Supply Chain Resource Sharing and Visibility
- 2020
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Ingår i: IFIP Advances in Information and Communication Technology. - Cham : Springer. ; , s. 259-266
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Konferensbidrag (refereegranskat)abstract
- Globalization, escalating competition, and demand for sustainable practices have required supply chain and production managers to consider various capabilities and value creation strategies for the customers. Rapid technological advancement in the current production environment calls for integrative and collaborative efforts for effective resource utilization and better visibility to gain competitive advantages. However, privacy risks and trust have always been a significant barrier for organizations’ efforts towards supply chain integration. Supply chain stakeholders fear these collaborate practices might weaken their bargaining power, accelerate risk of data manipulation and result in loss of information advantages. Addressing these issues, the study proposes a Blockchain-based collaborative model for production visibility and resource sharing. It demonstrates the framework for stakeholders’ interaction over a central procurement system backed with blockchain technology. The study further lays down the notion of production capacity backed smart contract rules. These smart contracts will run on the proposed blockchain network to reduce the possibilities of fraudulent transactions and capacity overbooking- leading to illegitimate subcontracting. The overall network will stimulate visibility and develop a technology-based trust among partners which ensuring sustainability by effective utilization of resources.
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| 5. |
- Agrawal, Tarun Kumar, et al.
(författare)
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Demonstration of a blockchain-based framework using smart contracts for supply chain collaboration
- 2023
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Ingår i: International Journal of Production Research. - : Informa UK Limited. - 0020-7543 .- 1366-588X. ; 61:5, s. 1497-1516
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Tidskriftsartikel (refereegranskat)abstract
- Blockchain technologies can support traceability, transparency and trust among participants. This has primarily been explored in established supply chains and not in the growing use of business networks or ecosystems, which is a notable limitation since supply chains typically are organised with a dominant actor that ensures common information systems and standards that negate blockchain benefits. Hence, this study explores the design of a blockchain-based collaborative framework for resource sharing using smart contracts. These are particularly well-suited for supporting operations in broader networks or ecosystems beyond supply chains with established collaborations and hierarchies. Based on a systematic literature review, a demonstrator framework was developed for stakeholder interactions through a procurement and distribution unit backed with blockchain technology. The framework consists of (a) network architecture to demonstrate partner interactions; (b) rules for network working principles based on supply collaboration requirements; (c) UML diagram to define smart contract interaction sequence; and (d) algorithm for smart contract network verification and validation. Applicability of these smart contracts was verified by deployment on an Ethereum blockchain. The demonstrator framework ensures quality and data authenticity in supply networks, so it is useful for effective resource utilisation in networks where outsourcing and production surpluses are major issues.
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| 6. |
- Agrawal, Tarun Kumar, et al.
(författare)
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Enabling circularity of electric vehicle batteries-the need for appropriate traceability
- 2021
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Ingår i: 2021 IEEE International Conference on Technology Management, Operations and Decisions, ICTMOD 2021. - : Institute of Electrical and Electronics Engineers (IEEE).
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Konferensbidrag (refereegranskat)abstract
- With the increased electrification of transportation, there is a growth in the number of electric vehicles (EV) in use, and hence also discarded EV batteries. It is critical to trace the batteries so that the policy of electrification does not lead to a negative impact on sustainability. To achieve the goals of circular economy, it is necessary to consider the sustainable extended life cycle strategies of reduce, reuse and recycle. Information gathering and sharing through the supply chain is the key driver for enabling the tracking and tracing of materials and services needed. Traceability indicators across the value chain may enable the creation of a comprehensive database that aids the circular economy goals. In this study, we discuss three different circular economy business models and identify the key traceability indicators for enabling circularity in the lithium-ion battery application in the automotive sector. Insights are used to develop a framework for viable EV battery circularity, capturing three key circular economy elements and four traceability characteristics for different circularity types.
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| 7. |
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| 8. |
- Agrawal, Tarun Kumar, 1989-, et al.
(författare)
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Understanding Supply Chain Visibility Through Experts’ Perspective: A Delphi Based Approach
- 2021
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Ingår i: Advances in Production Management Systems. Artificial Intelligence for Sustainable and Resilient Production Systems. - Cham : Springer Nature. ; 633 IFIP, s. 189-196
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Konferensbidrag (refereegranskat)abstract
- Visibility in production logistics and across the supply chain has become a key concern for organizations. Its need has been further emphasized due to the current COVID 19 crisis. Organizations find it challenging to prepare the internal logistics and supply chain, and quickly respond to such unexpected events, due to low visibility. Against this backdrop, the paper, which is a work-in-progress, systematically documents different factors influencing supply chain visibility and crucial information that should be collected and shared among supply chain partners for better visibility. A Delphi analysis is being conducted with twenty-six supply chain experts from various globally recognized enterprises with manufacturing units located worldwide. The study starts with a short open-ended questioner to collect a comprehensive list of antecedents, drivers, barriers, effects, and visibility information based on the qualitative response from the experts. The preliminary results from the first round of the Delphi analysis indicate that risk management, environmental sustainability, and supply chain control are some of the key drivers. Lack of IT infrastructure and maturity are some of the barriers, integrated systems, and technology maturity are among the key antecedents and gaining planning capability and better customer service are some of the positive effects of supply chain visibility as per the experts’ opinion. In addition, information related to planning, supplier location, and deviation are among the crucial ones that require the collection and sharing for better supply chain visibility. This research study is among the few that empirically explores factors influencing supply chain visibility and generates new insights as to why the barriers can be difficult to overcome in complex supply chain settings.
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| 9. |
- Agrawal, Tarun, 1989, et al.
(författare)
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Supply chain visibility: A Delphi study on managerial perspectives and priorities
- 2022
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Ingår i: International Journal of Production Research. - : Informa UK Limited. - 0020-7543 .- 1366-588X. ; 62:8, s. 2927-2942
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Tidskriftsartikel (refereegranskat)abstract
- Visibility across supply chains has been a key concern for organisations for many years, but the tools and information systems to achieve real-time visibility have not been available until recently. In response to uncertainty and complexity, advanced information and communication technologies have been explored for supply chain visibility (SCV). However, managerial perspectives are largely absent from the current literature. In response, this paper systematically documents managerial factors influencing SCV and information that should be collected and shared among supply chain partners for better visibility. A multi-stage Delphi analysis was conducted with 26 supply chain experts from various globally recognised enterprises with manufacturing units located worldwide. The results provide details on prioritised managerial perspectives and experiences within (1) factors affecting SCV (drivers, enablers, challenges and contingencies), (2) SCV content (supplier, internal and customer information) and (3) implications of SCV (capabilities and performance effects). One observation was that forecasting is not deemed as important due to severe disruptions in supply chains. Real-time visibility for better predictability emerged as the top priority. This study is among the few that empirically explores factors influencing supply chain visibility and generates new insights into why barriers can be difficult to overcome in complex supply chain settings.
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| 10. |
- Ai Jun, Hou, et al.
(författare)
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Variance based efficiency test of OMX index option markat
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Ingår i: European Journal of Finance. - 1351-847X .- 1466-4364.
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Tidskriftsartikel (refereegranskat)abstract
- n this paper, followed by the market efficiency definition of the absence of arbitrage opportunity in the market, we test the market efficiency of the OMXS30 index option market.We first check the arbitrage opportunity by examining the boundary conditions and thePut Call Parity that must be satisfied in the market. Then a variance based efficiency test is performed by establishing arisk neutral portfolio and re-balancing the initial portfolio in different trading strategies. In order to choose the most appropriate model for option price and hedging strategies, we calibrate several most applied models, i.e. the Black Scholes, Merton, Heston, Bates, and Affine Jump Diffusion models. Our results indicate that the Affine Jump Diffusion model significantly outperforms other models in the option price forecast and the trading strategies. Both the boundary and the Put Call Parity tests and the dynamic hedging strategy give evidence that no significant abnormal returns can be obtained in the OMXS30 option market, thereby supporting the market efficiency.
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| 11. |
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| 12. |
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| 13. |
- Baalsrud Hauge, Jannicke, 1969-, et al.
(författare)
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Digital and Physical Testbed for Production Logistics Operations
- 2020
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Konferensbidrag (refereegranskat)abstract
- Digitalisation and automation of existing processes are key factors for competitive industry, but still logistics operations are often dominated by manual work. A shift towards higher degree of automation within existing infrastructure is often challenged by high cost and complex processes, thus a return-on-investment is hardly achievable within decent time. The experience has shown that it is hard to assess all restrictions and interactions between new and old components before any new equipment or infrastructure is implemented and put into operation. This paper presents and discusses if the usage of digital twins representing and simulating a physical part can support the related assessing and decision-making processes. In this context, this paper presents a production logistics test-bed includes physical devices, an IoT-infrastructure and simulation software for innovation as well as operational management purposes.
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| 14. |
- Baalsrud Hauge, Jannicke, 1969-, et al.
(författare)
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Digital Twin Testbed and Practical Applications in Production Logistics with Real-Time Location Data
- 2021
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Ingår i: International Journal of Industrial Engineering and Management. - : Faculty of Technical Sciences. - 2217-2661. ; 12:2, s. 129-140
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Tidskriftsartikel (refereegranskat)abstract
- Nowadays, digital twins exist everywhere in various fields. However, an analysis of existing applications in manufacturing and logistics revealed that many entirely apply the concept. To identify when a complete implementation of the concept is beneficial, we analyse the need and the implications within production logistics. This study also presents an architecture supporting integrating a digital twin into production logistics and a corresponding application scenario. Based on this, we have derived practical applications. Each application is applied to different situations, and actual benefits can overcome the limitations of the previous studies.
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| 15. |
- Baalsrud Hauge, Jannicke, 1969-, et al.
(författare)
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Employing digital twins within production logistics
- 2020
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Ingår i: Proceedings of the 2020 IEEE International Conference on Engineering, Technology and Innovation (ICE/ITMC).
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Konferensbidrag (populärvet., debatt m.m.)abstract
- Digitalisation and automation of existing processes are key competitive factors for industry. Still, logistic operations often comprise manual effort, because the movement of goods and material places stringent requirements on the interactions between different systems, human-computer/robot-interaction as well as on changes in the operative processes. In general, the introduction and up-take of new enabling technologies, like the IoT, in complex systems evolved over decades, are challenging. The experience has shown that it is hard to assess all restrictions and interactions between new and old components before any new equipment or infrastructure is implemented and put in operation. This paper presents and discusses the usage of digital twins for supporting the decision-making processes in two different areas: Workstation design and logistics operation analysis. The results are based on tests and experiments carried out in a production logistics test-bed that includes physical devices, an IoT-infrastructure and simulation software. The digital twin is realised in a combination of using Unity and the simulation software IPS. The primary results show that there is no one-size fit all in terms of granularity of the underlying simulation model as well as for the reduction of reality in the digital twin, but the results also indicate that a context-aware digital twin supports the decision-making within a given scope.
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| 16. |
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| 17. |
- Barkhagen, Mathias
(författare)
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Risk-Neutral and Physical Estimation of Equity Market Volatility
- 2013
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The overall purpose of the PhD project is to develop a framework for making optimal decisions on the equity derivatives markets. Making optimal decisions refers e.g. to how to optimally hedge an options portfolio or how to make optimal investments on the equity derivatives markets. The framework for making optimal decisions will be based on stochastic programming (SP) models, which means that it is necessary to generate high-quality scenarios of market prices at some future date as input to the models. This leads to a situation where the traditional methods, described in the literature, for modeling market prices do not provide scenarios of sufficiently high quality as input to the SP model. Thus, the main focus of this thesis is to develop methods that improve the estimation of option implied surfaces from a cross-section of observed option prices compared to the traditional methods described in the literature. The estimation is complicated by the fact that observed option prices contain a lot of noise and possibly also arbitrage. This means that in order to be able to estimate option implied surfaces which are free of arbitrage and of high quality, the noise in the input data has to be adequately handled by the estimation method.The first two papers of this thesis develop a non-parametric optimization based framework for the estimation of high-quality arbitrage-free option implied surfaces. The first paper covers the estimation of the risk-neutral density (RND) surface and the second paper the local volatility surface. Both methods provide smooth and realistic surfaces for market data. Estimation of the RND is a convex optimization problem, but the result is sensitive to the parameter choice. When the local volatility is estimated the parameter choice is much easier but the optimization problem is non-convex, even though the algorithm does not seem to get stuck in local optima. The SP models used to make optimal decisions on the equity derivatives markets also need generated scenarios for the underlying stock prices or index levels as input. The third paper of this thesis deals with the estimation and evaluation of existing equity market models. The third paper gives preliminary results which show that, out of the compared models, a GARCH(1,1) model with Poisson jumps provides a better fit compared to more complex models with stochastic volatility for the Swedish OMXS30 index.
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| 18. |
- Barrera Diaz, Carlos Alberto, 1987-, et al.
(författare)
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Simulation-based multi-objective optimization for reconfigurable manufacturing system configurations analysis
- 2020
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Ingår i: Proceedings of the 2020 Winter Simulation Conference. - : IEEE. - 9781728194998 - 9781728195001 ; , s. 1527-1538, s. 1527-1538
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Konferensbidrag (refereegranskat)abstract
- The purpose of this study is to analyze the use of Simulation-Based Multi-Objective Optimization (SMO) for Reconfigurable Manufacturing System Configuration Analysis (RMS-CA). In doing so, this study addresses the need for efficiently performing RMS-CA with respect to the limited time for decision-making in the industry, and investigates one of the salient problems of RMS-CA: determining the minimum number of machines necessary to satisfy the demand. The study adopts an NSGA II optimization algorithm and presents two contributions to existing literature. Firstly, the study proposes a series of steps for the use of SMO for RMS-CA and shows how to simultaneously maximize production throughput, minimize lead time, and buffer size. Secondly, the study presents a qualitative comparison with the prior work in RMS-CA and the proposed use of SMO; it discusses the advantages and challenges of using SMO and provides critical insight for production engineers and managers responsible for production system configuration.
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| 19. |
- Bellgran, Monica, et al.
(författare)
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Decision support for production localization : Process, activities and localization factors
- 2013
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Konferensbidrag (refereegranskat)abstract
- Traditional production location decisions are mainly based upon economic factors while factors that facilitate decision makers in selecting the most suitable production location in terms of operations performance are rarely considered. Therefore, this paper presents a developed decision support for production localization that emphasises operational factors to be considered in the decision making. The research methodology combines a literature study with a multiple case study method. The findings are synthesised into a five phase decision process for making production localization decisions in practice. For each of these phases, key activities with related tools and expected output are developed.
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| 20. |
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| 21. |
- Bellgran, Monica, et al.
(författare)
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Green Performance Map : Handbok
- 2012
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Rapport (populärvet., debatt m.m.)abstract
- Denna handbok beskriver en enkel metod som kan användas av alla typer av teknikföretag som vill minska sin miljöbelastning från produktion. Metoden som presenteras i handboken kallas ”Green Performance Map” eller GPM-metoden. Den har utvecklats i forskningsprojektet ”Green production systems” som finansierats av VINNOVA:s program för Fordonsstrategisk forskning och innovation (FFI) under 2009-2012. Metoden är uppbyggd i olika aktivitetssteg: 0) Förberedelse 1) Identifiering av miljöaspekter 2) Prioritering av miljöaspekter 3) Handlingsplan 4) Implementering 5) Utvärdering av resultatet. Miljöaspekterna visualiseras i en input/outputmodell där processen man jobbar med delas in i fyra input-kategorier; värdeadderande material, tillsatsmaterial, energi och vatten, och fyra outputkategorier; produktiv output, restprodukter, utsläpp till luft/buller samt utsläpp till vatten/mark. Metoden gör det enkelt att visualisera miljöaspekterna på olika nivåer, antingen för hela företaget, ett produktionsavsnitt eller en specifik tillverkningsprocess. Grundtanken är att utgå från de miljöaspekter ett arbetslag kan påverka själv och få igång ett kontinuerligt förbättringsarbete som är bra för miljön samtidigt som det sparar pengar för företaget. Huvudsyftet med GPM-metoden är att inspirera företag att bredda engagemanget för miljöarbetet. Det behövs enkla verktyg för att stödja miljöförbättringsarbetet på alla nivåer i företaget på samma sätt som det idag finns en hel verktygslåda för införandet av Lean produktion. Många företag har idag redan en struktur för förbättringsarbete i produktionen. I dessa fall är det fördelaktigt att integrera även miljöförbättringsarbetet i den befintliga strukturen.
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| 22. |
- Bengtsson, Göran, et al.
(författare)
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Irregular walks and loops combines in small-scale movement of a soil insect : implications for dispersal biology
- 2004
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Ingår i: Journal of Theoretical Biology. - : Elsevier BV. - 0022-5193 .- 1095-8541. ; 231:2, s. 299-306
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Tidskriftsartikel (refereegranskat)abstract
- Analysis of small-scale movement patterns of animals we may help to understand and predict movement at a larger scale, such as dispersal, which is a key parameter in spatial population dynamics. We have chosen to study the movement of a soil-dwelling Collembola, Protaphorura armata, in an experimental system consisting of a clay surface with or without physical obstacles. A combination of video recordings, descriptive statistics, and walking simulations was used to evaluate the movement pattern. Individuals were found to link periods of irregular walk with those of looping in ahomogeneous environment as well as in one structured to heterogeneity by physical obstacles. The number of loops varied between 0 and 44 per hour from one individual to another and some individuals preferred to make loops by turning right and others by turning left. P. armata spent less time at the boundary of small obstacles compared to large, presumably because of a lower probability to track the steepness of the curvature as the individual walks along a highly curved surface. Food deprived P. armata had amore winding movement and made more circular loops than those that were well fed. The observed looping behaviour is interpreted in the context of systematic search strategies and compared with similar movement patterns found in other species.
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| 23. |
- Bengtsson, Göran, et al.
(författare)
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Statistical analysis of the influence of conspecifics on the dispersal of a soil collembola.
- 2002
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Ingår i: Theoretical Population Biology. - : Elsevier BV. - 1096-0325 .- 0040-5809. ; 61:2, s. 97-113
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Tidskriftsartikel (refereegranskat)abstract
- The evidence for dispersal activity among soil-living invertebrates comes mainly from observations of their movement on artificial substrates or of colonisation of defaunated soils in the field. In an attempt to elucidate the dispersal pattern of soil collembolans in the presence of conspecifics, statistical analyses were undertaken to describe and simulate the movement of groups of Onychiurus armatus released in trays of homogeneous soil. A chi(2) test was used to reject the null hypothesis that individuals moved independently of each other and uniformly in all directions. The mean radial distance moved (1-2 cm day(-1)) and the radial standard deviation varied temporally and with the density of conspecifics. To capture the interaction between the moving individuals, four dispersal models (pure diffusion, diffusion with drift interaction, drift interaction and synchronised diffusion, and drift interaction and behavioural mood), were formulated as stochastic differential equations. The parameters of the models were estimated by minimising the deviance between the observed replicates and replicates that were simulated using the models. The dynamics of movement were best described by modelling the drift interaction as dependent on whether individuals were in a social or an asocial mood.
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| 24. |
- Bernedixen, Jacob
(författare)
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Automated Bottleneck Analysis of Production Systems : Increasing the applicability of simulation-based multi-objective optimization for bottleneck analysis within industry
- 2018
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Manufacturing companies constantly need to explore new management strategies and new methods to increase the efficiency of their production systems and retain their competitiveness. It is of paramount importance to develop new bottleneck analysis methods that can identify the factors that impede the overall performance of their productionsystems so that the optimal improvement actions can be performed. Many of the bottleneck-related research methods developed in the last two decades are aimed mainly at detecting bottlenecks. Due to their sole reliance on historical data and lackof any predictive capability, they are less useful for evaluating the effect of bottleneck improvements.There is an urgent need for an efficient and accurate method of pinpointing bottlenecks, identifying the correct improvement actions and the order in which these should be carried out, and evaluating their effects on the overall system performance. SCORE (simulation-based constraint removal) is a novel method that uses simulation based multi-objective optimization to analyze bottlenecks. By innovatively formulating bottleneck analysis as a multi-objective optimization problem and using simulation to evaluate the effects of various combinations of improvements, all attainable, maximum throughput levels of the production system can be sought through a single optimization run. Additionally, post-optimality frequency analysis of the Pareto-optimal solutions can generate a rank order of the attributes of the resources required to achieve the target throughput levels. However, in its original compilation, SCORE has a very high computational cost, especially when the simulation model is complex with a large number of decision variables. Some tedious manual setup of the simulation based optimization is also needed, which restricts its applicability within industry, despite its huge potential. Furthermore, the accuracy of SCORE in terms of convergence in optimization theory and correctness of identifying the optimal improvement actions has not been evaluated scientifically.Building on previous SCORE research, the aim of this work is to develop an effective method of automated, accurate bottleneck identification and improvement analysis that can be applied in industry.The contributions of this thesis work include:(1) implementation of a versatile representation in terms of multiple-choice set variables and a corresponding constraint repair strategy into evolutionary multi-objective optimization algorithms;(2) introduction of a novel technique that combines variable screening enabled initializationof population and variable-wise genetic operators to support a more efficient search process;(3) development of an automated setup for SCORE to avoid the tedious manual creation of optimization variables and objectives;(4) the use of ranking distance metrics to quantify and visualize the convergence and accuracy of the bottleneck ranking generated by SCORE.All these contributions have been demonstrated and evaluated through extensive experiments on scalable benchmark simulation models as well as several large-scale simulation models for real-world improvement projects in the automotive industry.The promising results have proved that, when augmented with the techniques proposed in this thesis, the SCORE method can offer real benefits to manufacturing companies by optimizing their production systems.
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| 25. |
- Bjelkemyr, Marcus, et al.
(författare)
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Production Localization Factors: An Industrial and Literature Based Review
- 2013
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Ingår i: Proceedings of the 11th International Conference on Manufacturing Research (ICMR2013). - Cranfield, United Kingdom : International Conference on Manufacturing Research (ICMR). - 9781907413230 ; , s. 489-494
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Konferensbidrag (refereegranskat)abstract
- Decision are commonly based on the available or easily accessible information; this is also true for more complex assessments like production localization. Where to locate production is often a key strategic decisions that has great impact on a company’s profitability for a long time; insufficient business intelligence may therefore have grave consequences. Six production localization factor studies have been assessed to see if they are focusing on the same issues and if there are any gaps. A new approach for structuring localization factors and the localization process is then presented and assessed with regards to some previously identified critical issues.
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