| 1. |
- Alin, David, 1984, et al.
(författare)
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Reducing the EPEI-Time Using Discrete Event Simulation
- 2009
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Ingår i: Proceedings of the 2009 Swedish Production Symposium. ; :2, s. 295-301
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Konferensbidrag (refereegranskat)abstract
- One of the cornerstones in LEAN production is ‘make to order’, which requires small batch sizes and, thus, short Every Part Every Interval (EPEI) times. EPEI-time is defined as the time it takes to produce all product variants, before the first variant in the cycle returns in the schedule. However, many companies are reluctant to reduce their EPEI-times due to the increased number of set-ups. This skepticism is also supported by parts of existing theory, while other research contributions mean that companies often can reduce batch-sizes without affecting productivity. This paper presents a case study which uses discrete event simulation (DES) to evaluate the relation between EPEI-time and productivity. The results show that it is possible to reduce the EPEI-time and still maintain productivity and service levels to customers, without any investments. Increased variation in the production schedule evened out the load among the machines and, hence, the time lost in set-ups was gained in more parallel work.
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| 2. |
- Bokrantz, Jon, 1988, et al.
(författare)
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A Methodology for Continuous Quality Assurance of Production Data
- 2016
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Ingår i: Proceedings - Winter Simulation Conference. - 0891-7736. ; 2016-February, s. 2088-2099
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Konferensbidrag (refereegranskat)abstract
- High quality input data is a necessity for successful Discrete Event Simulation (DES) applications, and there are available methodologies for data collection in DES projects. However, in contrast to standalone projects, using DES as a day-to-day engineering tool requires high quality production data to be constantly available. Unfortunately, there are no detailed guidelines that describes how to achieve this. Therefore, this paper presents such a methodology, based on three concurrent engineering projects within the automotive industry. The methodology explains the necessary roles, responsibilities, meetings, and documents to achieve a continuous quality assurance of production data. It also specifies an approach to input data management for DES using the Generic Data Management Tool (GDM-Tool). The expected effects are increased availability of high quality production data and reduced lead time of input data management, especially valuable in manufacturing companies having advanced automated data collection methods and using DES on a daily basis.
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| 3. |
- Dettmann, Tobias, 1987, et al.
(författare)
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Startup Methodology for Production Flow Simulation Projects Assessing Environmental Sustainability
- 2013
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Ingår i: Proceedings of the 2013 Winter Simulation Conference. - 9781479920761 ; , s. 1926-1937
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Konferensbidrag (refereegranskat)abstract
- Environmental impact assessments for companies and products are important to increase sales and reduceenvironmental impact. To support improvements and detailed analyses, researchers have extended the useof simulation of production flows to include sustainability performance indicators. The research casesperformed until recently lack standardized methodology and thus have comparability issues and an increasenumber of common faults. By using a common methodology and gathering best practice, futurecases can gain a lot. Especially noted by the authors is that the project startup phase is critical for success.This paper proposes a methodology to support the startup phases of simulation projects with sustainabilityaspects in production flows. The methodology is developed and applied in an automotive industry studypresented in this paper. Using a rigid project startup, such as the proposed methodology, reduces iterationsduring modeling and data collection and decreases time spent on modeling.
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| 4. |
- Andersson, Jon, 1985
(författare)
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A HTTP web server starting files on the server screen, using QR-Codes and a REST architecture
- 2012
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Ingår i: The Code Project.
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- The Idea of presenting media on a screen using the mobile phones and QR-codes came up during a brainstorm meeting. There was a need to visualize information of our projects in some interactive way. With information and QR-codes printed on traditional paper sheets together with an interactive flat screen, the result would probable give the visitor some extra curiosity.An example of a application is a screen connected to a computer with the server application below. On the server you put four different movies. Under the screen you put four QR-codes corresponding to each movie. The visitor can then scan the QR-code with his/her mobile phone and start the corresponding movie on the screen. This is an simple implementation to achieve advanced interactivity
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| 5. |
- Andersson, Jon, 1985, et al.
(författare)
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Environmental Activity Based Cost using Discrete Event Simulation
- 2011
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Ingår i: Proceedings - Winter Simulation Conference. - 0891-7736. - 9781457721083 ; , s. 891-902
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Konferensbidrag (refereegranskat)abstract
- Discrete event simulation (DES) provides engineers with a flexible modeling capability for extensive analysis of a production flow and its dynamic behavior. Activity based costing (ABC) modeling can pro-vide additional knowledge about the monetary costs related to the manufacturing processes in DES. In addition, ABC modeling has been proposed as a tool for environmental impact analysis. Thus, previous studies have separately brought ABC into DES and ABC into environmental impact analysis. Bringing all three areas together, an ABC environmental simulation could provide deeper understanding about envi-ronmental impacts in the manufacturing processes than a regular Life Cycle Assessment (LCA) analysis. This paper proposes to use ABC modeling in conjunction with DES to perform a more detailed economic and environmental impact cost analysis. It is emphasized that the time to perform both analysis in one simulation is shorter or equal to perform them separately. Moreover, the approach can resolve some LCA problems.
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| 6. |
- Andersson, Jon, 1985, et al.
(författare)
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Environmental Impact Assessment for Manufacturing: Data Requirements for a Simulation-Based Approach
- 2012
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Ingår i: Swedish Production Symposium. - 9789175197524 ; , s. 151-160
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Konferensbidrag (refereegranskat)abstract
- The environmental footprint of products is an increasingly important measure for companies working to improve their sustainability performance, and the same measure has also become popular for marketing purposes. As a result, the demand for environmental product declarations and, thus, life cycle assessment (LCA) projects grows. To reap the full benefit from LCA studies in production systems analysis, LCA has more frequently been complemented with simulation of production flows (i.e. discrete event simulation) during the latest decade. Several examples of the DES-LCA combination in recent literature report substantial potential and successful implementations. However, a common problem is to establish efficient and credible procedures for collecting, analyzing, and representing the extensive amounts of input data required. The aim of this paper is therefore to provide recommendations for the management of environmental data in sustainability simulations. A review of seven previous DES-LCA projects provides a list of common sustainability parameters and experiences on how they should be collected and represented in simulation models. An important result is that deterministic representations appear to be enough for data not directly linked to production time. This finding makes it possible to replace time-consuming data gathering with collection of secondary data from public databases.
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| 7. |
- Andersson, Jon, 1985
(författare)
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Environmental Impact Assessment using Production Flow Simulation
- 2014
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- A higher-level perspective for production engineers and enables detailed assessment of dynamic manufacturing systems environmental impact at a system level. By using simulation, the simulation engineer enables to understand how minor adjustments affect the system. This thesis shows how to use simulation of manufacturing systems with an environmental sustainability focus. Thus, analyse the system from both an economical and environmental perspective at simultaneous. Static assessments have been the main approach analysing systems environmental impact. Dynamic manufacturing systems cannot be modelled statically properly. Static assessment lacks the ability to predict how the system operates and react after adjustments of the system. However, dynamic simulations of systems are data intensive and require more resources and knowledge. This thesis elaborates on when to use simulation of manufacturing systems to assess environmental impact. In short, simulation of manufacturing system can be efficient when there is a need for both productivity assessment and environmental assessment.This thesis used action research in two industrial cases to advance a methodology using simulation for environmental assessment of manufacturing systems. The initial methodology is developed from a literature review of previous studies and interviews with practitioners.Current commercial software lacks out of the box support for the functionalities supporting the assessment proposed in this thesis. However, most existing software tools are possible to use due to the high adaptation potentials. This thesis proposes a set of new functionalities needed to support the proposed methodology in this thesis. A developed demonstration software presented in the thesis implements the functionalities. The result is a very simple demonstration tool to be used by production engineers with low experience of simulation.
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| 8. |
- Andersson, Jon, 1985, et al.
(författare)
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Evaluation of methods used for life-cycle assessments in Discrete Event Simulation
- 2012
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Ingår i: Proceedings - Winter Simulation Conference. - 0891-7736. - 9781467347792
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Konferensbidrag (refereegranskat)abstract
- The incitements from society for life-cycle assessment (LCA) and credible ecolables are ever-increasingand often important for successful marketing of products. Robust assessment methods are important forcomparable, useful and trustworthy LCAs and ecolables. In order to improve the metrics of a product’secolable, is it important to fully understand its production system. Discrete Event Simulation (DES)models are able to provide more detailed information than traditional LCA approaches. Therefore,methods used to combining LCA in DES have been developed during the last decade. The combinedapproaches have matured and the experiences grown. This article compares six previous cases and aims tosummarize and discuss their experiences to aid future development. The results show where it isspecifically important to make good decisions throughout the modeling methodology, for example goaland scope definition, trustworthy input data for sensitive parts, and communicable impact categories.
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| 9. |
- Andersson, Jon, 1985, et al.
(författare)
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Framework for Ecolabeling using Discrete Event Simulation
- 2012
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Ingår i: Proceedings of the 2012 spring simulation multiconference.
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Konferensbidrag (refereegranskat)abstract
- Ecolabled products have shown a competitive advantage to other products. Regulatory changes and market pressure creates an increased need for environmental impact assessments. The dominating method for environmental impact assessments - life cycle assessment (LCA) lacks support to properly analyze the dynamic aspects of business operations and production processes. This Paper proposes to use discrete event simulation to support more extensive and detailed environmental assessments on selected parts of the production process, keeping simplicity for parts of less importance and interest.
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| 10. |
- Andersson, Jonny K, 1972, et al.
(författare)
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Hand, Wrist, and Forearm Injuries in Male Professional Soccer Players: A Prospective Cohort Study of 558 Team-Seasons From 2001-2002 to 2018-2019
- 2021
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Ingår i: Orthopaedic Journal of Sports Medicine. - : SAGE Publications. - 2325-9671. ; 9:1
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Tidskriftsartikel (refereegranskat)abstract
- Background: The literature on upper extremity injuries in professional soccer players is scarce, and further insight into the onset and cause of these injuries as well as potential differences between goalkeepers and outfield players is important. Purpose: To investigate the epidemiology of hand, wrist, and forearm injuries in male professional soccer players between 2001 and 2019. Study Design: Descriptive epidemiology study. Methods: Between the 2001-2002 and 2018-2019 seasons, 120 European male soccer teams were followed prospectively for a varying number of seasons (558 team-seasons in total). Time-loss injuries and player-exposures to training sessions and matches were recorded on an individual basis in 6754 unique players. Injury incidence was reported as the number of injuries per 1000 player-hours, and between-group differences were analyzed using Z statistics and rate ratios (RRs) with 95% CIs. Between-group differences in layoff time were analyzed. Results: In total, 25,462 injuries were recorded, with 238 (0.9%) of these affecting the hand (71.4%; n = 170), wrist (16.8%; n = 40), and forearm (11.8%; n = 28), producing an incidence of 0.065 injuries per 1000 hours. A majority of the injuries were traumatic with an acute onset (98.7%; n = 235). Fractures were the most common injuries recorded (58.8%; n = 140), often involving the metacarpal bones (25.2%; n = 60) and phalanges (10.1%; n = 24). The injury incidence was significantly higher for goalkeepers (115 injuries; 0.265 per 1000 hours) compared with outfield players (123 injuries; 0.038 per 1000 hours) (RR, 7.0 [95% CI, 5.4-9.0]). Goalkeepers also had a significantly longer mean layoff time than outfield players (23 +/- 27 vs 15 +/- 27 days; P = .016). Conclusion: Injuries to the hand, wrist, and forearm constituted less than 1% of all time-loss injuries in male professional soccer players. Fractures were most common and constituted more than half of all injuries. Goalkeepers had a 7-fold higher incidence and an over 1-week longer mean layoff time compared with outfield players.
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| 11. |
- Andersson, Jon, 1985
(författare)
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Life cycle assessment in production flow simulation for production engineers
- 2013
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Ingår i: 22nd International Conference on Production Research.
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Konferensbidrag (refereegranskat)abstract
- Product developers are the main target for environmental impact assessment. Every day operation in manufacturing industry considers only site-specific aspects as energy consumption or material usage. Moreover, those aspects are mainly in-place for economic reasons. Discrete event simulation is widely used by industry for problem solving on a factory and logistic level. Including life cycle assessment in simulation models enable detailed assessment for production system. Yet, it requires specialization to create robust environmental models in discrete event simulation. Simplified software supporting production engineers in modelling and data harvesting reduce specialist requirements. This paper present a first version of software developed for the production engineers. The software supports modelling and analyses using discrete event simulation models with life cycle assessment.
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| 12. |
- Andersson, Jon, 1985
(författare)
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Life cycle assessment in production simulation used by production engineers
- 2013
-
Ingår i: 22nd International Conference on Production Research, ICPR 2013.
-
Konferensbidrag (refereegranskat)abstract
- Product developers are the main target for environmental impact assessment. Every day operation in manufacturing industry considers only site-specific aspects as energy consumption or material usage. Moreover, those aspects are mainly in-place for economic reasons. Discrete event simulation is widely used by industry for problem solving on a factory and logistic level. Including life cycle assessment in simulation models provide detailed assessment for production system. Yet, it requires specialization to create robust environmental models in discrete event simulation. Simplified software supporting production engineers in modelling and data harvesting reduce specialist requirements. This paper present a first version of software developed for the production engineers. The software supports modelling and analyses using discrete event simulation models with life cycle assessment.
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| 13. |
- Barletta, Ilaria Giovanna, 1988, et al.
(författare)
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Assessing a proposal for an energy-based overall equipment effectiveness indicator through discrete event simulation
- 2015
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Ingår i: Proceedings - Winter Simulation Conference. - 0891-7736. - 9781479974863 ; 2015-January, s. 1096-1107
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Konferensbidrag (refereegranskat)abstract
- New challenges demand that manufacturing companies adopt sustainable approaches and succeed in this adoption. Energy efficiency plays a key role in achieving sustainability goals, and performance indicators are necessary beyond measurement of data to evaluate energy efficiency. In this landscape, scalable and easy-to-understand metrics providing an energy competitiveness degree of manufacturing resources are currently missing. The study aims to test through simulation applicability and potential offered by a novel Energy Overall Equipment Effectiveness - Energy OEE - indicator for discrete manufacturing firms. A simulation of a discrete manufacturing CNC machine case is used to evaluate the applicability of using Energy OEE assessment for management decision support. As a result, this study paves the way to a better exploitation of data that energy monitoring and sensor technology aim to offer in the future.
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| 14. |
- Gavali, Hamid, et al.
(författare)
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Outcome of Radical Surgical Treatment of Abdominal Aortic Graft and Endograft Infections Comparing Extra-anatomic Bypass with In Situ Reconstruction : A Nationwide Multicentre Study
- 2021
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Ingår i: European Journal of Vascular and Endovascular Surgery. - : Saunders Elsevier. - 1078-5884 .- 1532-2165. ; 62:6, s. 918-926
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Tidskriftsartikel (refereegranskat)abstract
- Objective: Abdominal aortic graft and endograft infection (AGI) is primarily treated by resection of the infected graft and restoration of distal perfusion through extra-anatomic bypass (EAB) or in situ reconstruction/repair (ISR). The aim of this study was to compare these surgical strategies in a nationwide multicentre retrospective cohort study.Methods: The Swedish Vascular Registry (Swedvasc) was used to identify surgically treated abdominal AGIs in Sweden between January 1995 and May 2017. The primary aim was to compare short and long term survival, as well as complications for EAB and ISR.Results: Some 126 radically surgically treated AGI patients were identified – 102 graft infections and 24 endograft infections – treated by EAB: 71 and ISR: 55 (23 neo-aorto-iliac systems, NAISs). No differences in early 30 day (EAB 81.7% vs. ISR 76.4%, p =.46), or long term five year survival (48.2% vs. 49.9%, p =.87) were identified. There was no survival difference comparing NAIS to other ISR strategies. The frequency of recurrent graft infection during follow up was similar: EAB 20.3% vs. ISR 17.0% (p =.56). Survival and re-infection rates of the new conduit did not differ between NAIS and other ISR strategies. Age ≥ 75 years (odds ratio [OR] 4.0, confidence interval [CI] 1.1 – 14.8), coronary artery disease (OR 4.2, CI 1.2 – 15.1) and post-operative circulatory complications (OR 5.2, CI 1.2 – 22.5) were associated with early death. Prolonged antimicrobial therapy (> 3 months) was associated with reduced long term mortality (HR 0.3, CI 0.1 – 0.9).Conclusion: In this nationwide multicentre study comparing outcomes of radically treated AGI, no differences in survival or re-infection rate could be identified comparing EAB and ISR.
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| 15. |
- Gavali, Hamid, et al.
(författare)
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Semi-Conservative Treatment Versus Radical Surgery in Abdominal Aortic Graft and Endograft Infections
- 2023
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Ingår i: European Journal of Vascular and Endovascular Surgery. - : Elsevier. - 1078-5884 .- 1532-2165. ; 66:3, s. 397-406
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Tidskriftsartikel (refereegranskat)abstract
- Objective: Abdominal aortic graft and endograft infections (AGIs) are rare complications following aortic surgery. Radical surgery (RS) with resection of the infected graft and reconstruction with extra-anatomical bypass or in situ reconstruction is the preferred therapy. For patients unfit for RS, a semi-conservative (SC), graft preserving strategy is possible. This paper aimed to compare survival and infection outcomes between RS and SC treatment for AGI in a nationwide cohort.Methods: Patients with abdominal AGI related surgery in Sweden between January 1995 and May 2017 were identified. The Management of Aortic Graft Infection Collaboration (MAGIC) criteria were used for the definition of AGI. Multivariable regression was performed to identify factors associated with mortality.Results: One hundred and sixty-nine patients with surgically treated abdominal AGI were identified, comprising 43 SC (14 endografts; 53% with a graft enteric fistula [GEF] in total) and 126 RS (26 endografts; 50% with a GEF in total). The SC cohort was older and had a higher frequency of cardiac comorbidities. There was a non-significant trend towards lower Kaplan -Meier estimated five year survival for SC vs. RS (30.2% vs. 48.4%; p = .066). A non-significant trend was identified towards worse Kaplan -Meier estimated five year survival for SC patients with a GEF vs. without a GEF (21.7% vs. 40.1%; p = .097). There were significantly more recurrent graft infections comparing SC with RS (45.4% vs. 19.3%; p < .001). In a Cox regression model adjusting for confounders, there was no difference in five year survival comparing SC vs. RS (HR 1.0, 95% CI 0.6 -1.5).Conclusion: In this national AGI cohort, there was no mortality difference comparing SC and RS for AGI when adjusting for comorbidities. Presence of GEF probably negatively impacts survival outcomes of SC patients. Rates of recurrent infection remain high for SC treated patients.
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| 16. |
- Jain, Sanjay, et al.
(författare)
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A Hierarchical Approach for Evaluating Energy Trade-offs in Supply Chains
- 2013
-
Ingår i: International Journal of Production Economics. - : Elsevier BV. - 0925-5273. ; 146:2, s. 411-422
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Tidskriftsartikel (refereegranskat)abstract
- Supply chain design and operational decisions may impact the energy needed to keep the products flowing through to the customers. It is a challenge to determine the energy consumption and even more challenging to understand the impact of design and operational decisions on the energy consumption along the supply chain. This paper presents a hierarchical simulation based approach for estimating the energy consumption to keep the products flowing through a supply chain. System dynamics simulation is used at a high abstraction level to understand the major factors that may affect the energy consumption. Discrete event simulation is then used to delve down in detail for evaluating the critical stages in the supply chain. A case study for a closed loop supply chain of forklift brakes is used as an example of application of the approach. (C) 2013 Elsevier B.V. All rights reserved.
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| 17. |
- Jain, Sanjay, et al.
(författare)
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Multi-Resolution Modeling for Supply Chain Sustainability Analysis
- 2013
-
Ingår i: Proceedings of the 2013 Winter Simulation Conference. - 9781479920778 ; , s. 1996-2007
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Konferensbidrag (refereegranskat)abstract
- Consumers are increasingly becoming conscious of the need to reduce environmental impact. This hasmotivated the industry to make efforts to improve the sustainability of their products and supply chains.Such efforts require the ability to analyze the sustainability of supply chains and potential improvements.A systematic approach is needed to evaluate the alternatives that may range from those at the supplychain configuration level to those for improving equipment at a production facility. This paper presents amulti-resolution modeling approach that allows analyzing parts of the supply chain at appropriate level ofdetail. The capability allows studying the supply chain at high level initially and iteratively drilling downto detailed levels in the identified areas of opportunity and evaluating associated improvement alternatives.Multi-resolution modeling directly relates the impact of improvement in one part of the supplychain to overall supply chain performance thus reducing analyst effort and time.
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| 18. |
- Johansson, Björn, 1975, et al.
(författare)
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Evaluation and Calculation of Dynamics in Environmental Impact Assessment
- 2013
-
Ingår i: IFIP Advances in Information and Communication Technology. - Berlin, Heidelberg : Springer Berlin Heidelberg. - 1868-4238 .- 1868-422X. - 9783642403514 ; 397:1, s. 135-141
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Konferensbidrag (refereegranskat)abstract
- In ten years customers will select products not only based on price and quality but also with strong regard to the product value environmental footprint, including for example the energy consumed. Customers expect transparency in the product realization process, where most products are labeled with their environmental footprint. Vigorous companies see this new product value as an opportunity to be more competitive. In order to effectively label the envi-ronmental impact of a product, it is pertinent for companies to request the envi-ronmental footprint of each component from their suppliers. Hence, companies along the product lifecycle require a tool, not only to facilitate the computing of the environmental footprint, but also help reduce/balance the environmental impact during the lifecycle of the product. This paper proposes to develop a procedure that companies will use to evaluate, improve and externally advertise their product’s environmental footprint to customers.
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| 19. |
- Johansson, Björn, 1975, et al.
(författare)
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Power Level Sampling of Metal Cutting Machines for Data Representation in Discrete Event Simulation
- 2015
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Ingår i: International Journal of Production Research. - : Informa UK Limited. - 0020-7543 .- 1366-588X. ; 53:23, s. 7060-7070
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Tidskriftsartikel (refereegranskat)abstract
- An extension to the application area for discrete event simulation (DES) has been ongoing since the last decade and focused only on economic aspects to include ecologic sustainability. With this new focus, additional input parameters, such as electrical power consumption of machines, are needed. This paper aim at investigating how NC machine power consumption should be represented in simulation models of factories. The study includes data-sets from three different factories. One factory producing truck engine blocks, one producing brake disc parts for cars and one producing forklift components. The total number of data points analysed are more than 2,45,000, where of over 1,11,000 on busy state for 11 NC machines. The low variability between busy cycles indicates that statistical representations are not adding significant variability. Furthermore, results show that non-value-added activities cause a substantial amount of the total energy consumption, which can be reduced by optimising the production flow using dynamic simulations such as DES.
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| 20. |
- Thiede, Sebastian, et al.
(författare)
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Environmental aspects in manufacturing system modelling and simulation – State of the art and research perspectives
- 2013
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Ingår i: CIRP Journal of Manufacturing Science and Technology. - : Elsevier BV. - 1755-5817 .- 1878-0016. ; 6:1, s. 78-87
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Tidskriftsartikel (refereegranskat)abstract
- The efficient and effective usage of energy and resources is of rising importance in manufacturing companies. This paper argues that manufacturing system simulation is a promising way to realistically cope with those issues and simultaneously consider them with traditional target dimensions. Against this background, the paper analyses whether commercial simulation tools are already capable to address those aspects. It turns out that environmentally related aspects are currently not sufficiently considered as standard functions. Therefore, based on the analysis of on-going research work, different directions for further development are presented and discussed.
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