| 1. |
- Lennartsson, Martin
(författare)
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The transition of industrialised house-building towards improved production control
- 2012
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Production control is the coordination of supply chain and production activities within manufacturing systems to achieve specific delivery flexibility and delivery reliability with a minimum of cost. Swedish industrialised house-building is a part of housing construction, employing an engineer-to-order production strategy, meaning that products (buildings) are engineered (designed) and produced to order. The building system is used as a strategic asset, giving flexibility to the client and aiming for production standardisation (e.g. operations, material) and predictability (e.g. quality and delivery times) of the production. Still, the operational platform encounters problems resulting in severe rework, which impact on quality and time frames.This thesis describes the transition for industrialised house-building towards improved production control by assessing tools from other manufacturing typologies than industrialised housing and engineer-to-order. The aim of the assessment was to identify barriers against the transition. When assessing tools from other fields it is important that the analysis relates to the business model employed i.e. avoid the risk that measures introduced to the operational platform compromise the flexibility of the end product (the building).The tools were decided from a decision base methodology, which is a combination of a model for competitive capabilities and the three areas product, process and supply chain. The investigated tools were modularity, Systematic production Analysis (SPA) and Failure mode and Effect Analysis (FMEA). Empirical data were gathered from the production process of an industrialised house-builder and one of their first-tier suppliers. The results show that the tools have to be changed to fit in the industrialised house-building company. SPA was for example deconstructed with the idea to iteratively add back removed parts. In the FMEA study, the tool was also revised by suggesting new ranking systems to prioritise failure modes in production and the idea to reflect the industrial context of the house-builder and engineer-to-order. Especially indicative was the interaction between the severity and detection classes and the length of the supply chain.The most prominent barriers for production control identified in the assessment were product design in terms of interfaces and their tolerances, lack of testing in the production (exacerbated by the process length), choice of wood as the structural material, orders dispatched to the factory project-by-project, and lack of vertical integration among consultants and suppliers. Also, in the investigation of the transition towards improved production control, the assessment of the tools showed that it should be managed in a stepwise manner. Consequently, the impact from the tools on both the operational platform but also the business model can be monitored.
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| 2. |
- Andersson, Martin, et al.
(författare)
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The anomalous hyperfine structure of Al II
- 2012
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Ingår i: Journal of Physics B: Atomic, Molecular and Optical Physics. - : IOP Publishing. - 0953-4075 .- 1361-6455. ; 45:13
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Tidskriftsartikel (refereegranskat)abstract
- The hyperfine structure of a large number of transitions in Al II cannot be described using A and B hyperfine constants and the hyperfine structure is therefore said to be anomalous. In this paper, we have studied the hyperfine structure of a few transitions in Al II, 3s5s(3)S-3s5p(3)P, 3s4d(3)D-3s5p(3)P and 3s5p(3)P-3s5d(3)D, by combining theory and experiment. It is shown that the anomalous hyperfine structure is due to strong off-diagonal hyperfine interaction resulting not only in a deplacement of the energies of the hyperfine levels, but also resulting in large intensity redistribution among the individual hyperfine lines. It is shown that the hyperfine mixing in 3s4d(3)D and 3s5d(3)D is very large, whereas small but not negligible in 3s5p(3)P. By combining experimental spectra and theory we could obtain accurate wavefunctions for the 3s4d(3)D and 3s5d(3)D hyperfine levels which were used to calculate the gf-values of all individual hyperfine transitions not only for 3s5p(3)P, but also for 3s3p(3)P and 3s4p(3)P, where the off-diagonal hyperfine interaction leads to negligible intensity redistribution.
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| 3. |
- André, Samuel, 1986-, et al.
(författare)
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Exploring the design platform in industrialized housing for efficient design and production of customized houses
- 2019
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Ingår i: Transdisciplinary engineering for complex socio-technical systems. - Amsterdam : IOS Press. - 9781643680200 - 9781643680217 ; , s. 125-134
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Konferensbidrag (refereegranskat)abstract
- Industrialized house-building (IHB) is a sector offering unique products by adopting an engineer-to-order (ETO) strategy. Customer satisfaction is achieved by adaptation of product solutions and the fast-paced introduction of new technology in combination with short lead-times and cost-efficient production. Product platforms is acknowledged as a strategic enabler for mass customization and increased competitiveness. The strategy has been a necessity in the mechanical industry for several decades. However, for IHB, platforms have only gained interest in recent years. In general, ETO companies struggle with adopting the common product platform approach, set by pre-defined modules and components. Predefinitions require standardization of the product offer which reduces the customization ability which is regarded as a competitive edge. The Design Platform (DP) approach was developed aimed to support ETO companies by utilizing different types of engineering assets in a coherent transdisciplinary model enabling efficient customization. The long-term aim of this work is to investigate and support the DP applicability in IHB to increase efficiency in development and delivery. For this article, data were gathered from a single case study, including workshops with company representatives combined with interviews and document analysis. Based on the data analysis, engineering assets were identified and characterized. Further, a conceptual PLM solution is proposed and outlined to support the DP application combined with the assets. The results suggest that a PLM system can host parts of the DP and that it is applicable in IHB.
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| 4. |
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| 5. |
- Areth Koroth, Rohith, et al.
(författare)
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A method to capture and share production requirements supporting a collaborative production preparation process
- 2023
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Ingår i: Proceedings of the Design Society. - Cambridge : Cambridge University Press. ; , s. 273-282
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Konferensbidrag (refereegranskat)abstract
- The production preparation process (3P) enables collaboration between design and production engineers during product development but its efficiency is limited by the abundance of documentation of manufacturing constraints and capabilities. Empirical studies showed that use of production requirements can increase the efficiency of 3P, however, the support for production engineers to capture and share production requirements is scarce. A method to support production engineers in identifying, defining, structuring and sharing production requirements and collaborating with design engineers is presented. The method has three major parts - focus areas and requirement categories, a worksheet for production requirements capturing and prioritization, and a workflow for using the worksheet. The method was developed in collaboration with practitioners and contributes to the existing knowledge by providing production engineers with a structured way of working with production requirements. Evaluation of the method in the case company showed its usability when developing product variants and that additional work is needed to support the development of new product families and assembly lines.
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| 6. |
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| 7. |
- Areth Koroth, Rohith, et al.
(författare)
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Aligning production requirements with product and production maturities : enhancing production preparation during product development
- 2024
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Ingår i: Proceedings of the Design Society. - : Cambridge University Press. ; , s. 195-204
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Konferensbidrag (refereegranskat)abstract
- Product development is multidisciplinary with high uncertainties necessitating coordinated decision-making between design and production. This paper presents a method to work with production requirements to support production preparation during product development aligned with different product and production maturities. The work was conducted in collaboration with two global manufacturing firms. The method supports identification, definition, and structuring of production requirements and the collaboration between design and production engineers for requirement prioritization and follow-up.
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| 8. |
- Areth Koroth, Rohith, et al.
(författare)
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Design for Producibility : A Case Study on Theory, Practice and Gaps
- 2022
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Ingår i: Transdisciplinarity and the Future of Engineering. - Amsterdam : IOS Press. - 9781643683386 - 9781643683393 ; , s. 134-143
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Konferensbidrag (refereegranskat)abstract
- Changing customer requirements, regulations, technology and regulations, shift to automated assembly and product variety are common challenges faced by many manufacturing industries and alignment between product and production system is critical for business success. Design engineers should be aware of production constraints and capabilities to ensure efficient manufacture and assembly of products that are developed. This requires different and detailed support to guide the work, evaluate different design solutions, enable continuous and concurrent work with design for producibility and production preparation. A study was conducted in three companies to understand alignment and integration of product development and production preparation processes. Also, utilization of production requirements, design for manufacture and assembly (DFMA) and failure modes and effect analysis (FMEA) to support design for producibility (DFP) was studied. Currently, production preparation is done through discussions between design and production engineers. Production preparation and work with DFMA and FMEA is skill and experience dependent. Definition, structuring and sharing of production requirements on different system levels, from production and product perspectives are identified as critical to supporting design for producibility and production preparation. The work with FMEA and DFMA can be developed and improved with systematic and structured way of working with production requirements.
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| 9. |
- Areth Koroth, Rohith, et al.
(författare)
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Product Platforms and Production : Current State and Future Research Directions Targeting Producibility and Production Preparation
- 2021
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Ingår i: Transdisciplinary Engineering for Resilience: Responding to System Disruptions. - Amsterdam : IOS Press. - 9781643682082 - 9781643682099 ; , s. 332-341
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Konferensbidrag (refereegranskat)abstract
- New business opportunities are created when the advantage of changeable manufacturing systems expand beyond increased freedom in production location to increased freedom in product design. However, there are new challenges to overcome, including improved ability to design and adapt products when requirements from stakeholders quickly change and/or new technology rapidly evolves. Simultaneously, the producibility of each design must be ensured while keeping the lead-time of the whole process to the minimum. Changeable product platforms (both flexible and adaptable platforms) are gaining attention in both research and industry. However, the level of alignment and integration of product development and production is critical for the efficiency of the product realization process. In this study, we map the state of practice in five companies with an initial literature review. The companies had no formal platform strategy and faced challenges with variant management and development time, had manual processes for production preparation and reuse of technical solutions and knowledge happened through components and documents. The production preparation and reuse were dependent on the engineer’s competence. Future work will concentrate on identifying how manufacturing inputs can be added as a design asset in a changeable product platform to enhance producibility and production preparation.
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| 10. |
- Areth Koroth, Rohith
(författare)
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Supporting production preparation during product development using production requirements
- 2023
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Product development is affected by uncertainties due to changing customer requirements, changing regulations, technological developments, long lead times, high product complexities, and geopolitical issues. Automation, increased flexibility of production, and reduced lead times are drivers that allow product development to be competitive in this scenario. Design engineers should be aware of production capabilities to facilitate early producibility assessments and to avoid late changes. Production preparation is identified as an important activity in the product development process, whereby the producibility of a product is assessed. In this thesis, the current state of production preparation during product development is investigated and a method is introduced supporting production preparation using production requirements. The work was carried out using the design research methodology framework and comprised four studies based on the four steps of the framework. The research clarification and descriptive study 1 phases aimed at developing understanding and were done by means of data collection at the companies through interviews and document studies. The next two steps were prescriptive study and descriptive study 2, which aimed at developing and evaluating the support. This was done through observation, workshops, and solution development. The production preparation process is supported by Design for Manufacturing and Assembly, failure mode and effects analysis, lesson-learnt documents, and computer-aided design, and the efficiency of the process is dependent on individual skills and knowledge. Tools to support common understanding, remove ambiguity in requirements, and enable collaboration between design and production engineers are needed. The developed method allows for the identification, definition, structuring, and sharing of production requirements, aligning with varying maturities of product and production systems during product development. This helps improve the collaboration between design and production engineers for production preparation.
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