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- Hilletofth, Per
(författare)
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Differentiated Supply Chain Strategy - Response to a fragmented and complex market
- 2008
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Supply Chain Management (SCM) aims to synchronize the requirements of customers with the flow of materials from suppliers, in order to satisfy the needs of the customers as costefficiently as possible. This has become a difficult task due to several developments in the market, such as increased competition, increased demand variability, increased product variety, increased amounts of customer-specific products, and shortening product life cycles. These developments, due in part to globalization, provide additional management challenges and new practices in which supply chains are designed and managed, and can eventually make the difference between companies staying competitive or not. The overall purpose of this thesis is to investigate how complexity and globalization affect supply chain design and operations. The main emphasis has been on producing descriptive results of the studied phenomenon. This research involves five case studies covering international transportation structures used in SCM, the selection of supply chain strategies in different business environments, and the role of information systems and technology in achieving the objective of SCM. In this thesis it has been concluded that in order to cope with increasingly complex and fragmented markets companies need more differentiated transportation structures, modes, and supply chains. Furthermore, to effectively manage this, information systems and advanced decision support tools are required. In addition, this thesis has shown that current taxonomies for supply chain strategy selection are too simplistic due to three major problems: they mediate that it is a question of choosing one supply chain strategy for the entire company,they regard markets as rather homogeneous, and they link each supply chain strategy to a specific business context. Instead, it has been concluded that in order to better satisfy differing customer needs in various markets it is increasingly necessary to develop a differentiated supply chain strategy by utilizing different manufacturing and delivery strategies concurrently. Thus, a need exists for new taxonomies for supply chain strategy selection which recognize that the markets are becoming more fragmented and complex, that customer preferences differ across customer/market segments, and that there is a need to differentiate the supply chain strategy. This thesis also highlights several requirements of a differentiated supply chain strategy. Firstly, extended supply chain collaboration is required, since a differentiated supply chain strategy will involve more supply chain partners than a traditional supply chain strategy. Secondly, there is a need for more transportation mode alternatives, particularly intermodal, both in supply and distribution operations, due to the fact that differentiation requires diversity. In this thesis, intermodal landbridge freight services are highlighted as one interesting avenue, which could potentially facilitate a more differentiated supply chain strategy. Thirdly, more integrated information systems are needed along with decision support tools. This study illustrates that agent based modeling appears to be an interesting method for developing realistic decision support tools in the context of complex supply chains. An interesting aspect for further research is to investigate how different manufacturing and delivery strategies can be used concurrently in international supply chains. Moreover, there are several requirements and opportunities of a differentiated supply chain strategy, and these have to be investigated further
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| 2. |
- Hillman, Karl, 1978, et al.
(författare)
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Cumulative causation in biofuels development: a critical comparison of the Netherlands and Sweden
- 2008
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Ingår i: Technology Analysis and Strategic Management. - : Informa UK Limited. - 0953-7325 .- 1465-3990. ; 20:5, s. 593-612
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Tidskriftsartikel (refereegranskat)abstract
- Supporting the development and diffusion of sustainable innovations has become a dominant topic on the political agenda of many countries. However, this has proven to be a difficult task. To increase insight in such processes, this paper takes biofuel technologies in the mobility sector as the topic of a comparative case study. Various national governments have supported innovation trajectories around biofuels. We analyse, assess and compare two such trajectories as they have developed so far: one in the Netherlands and one in Sweden. A Technological Innovation System (TIS) approach is applied. A TIS is constituted by actors, networks and institutions, that are to be gradually constructed around a technology. We analyse whether governments and entrepreneurs have succeeded in developing seven key processes, or system functions, necessary for the development and diffusion of biofuel technologies. By analysing the build-up of system functions over time we identify virtuous and vicious forms of cumulative causation. The Dutch and Swedish TISs for biofuels are followed from 1990 to 2005. Our comparison shows that, due to a variety in function fulfilment and the emergence of cumulative causation, the Swedish TIS has reached a market expansion and broad social implementation of biofuels, whereas the Dutch TIS has established considerably less.
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| 3. |
- Hillman, Karl
(författare)
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Environmental Assessment and Strategic Technology Choice : The Case of Renewable Transport Fuels
- 2008
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The scale of the required changes is huge, and time is limited if we are to avoid the most severe effects of climate change. To reduce greenhouse gas emissions from road transport, several fuels and electricity originating from renewable energy sources have been proposed, all of them in different stages of development and with various and shifting environmental impacts. This thesis aims at increasing the usefulness of environmental assessments of emerging technologies as a basis for strategic technology choice. Recommendations for the design and interpretation of such assessments are presented, with a special focus on life cycle assessment (LCA) methodology. A long time perspective, the possibility of system change, and the inclusion of socio–technical change processes allows for the revision of methodological assumptions normally made in LCA of current products. To guide the selection of technologies, there is need for assessment both of technology and of interventions. For the assessment of technology, an attributional approach is applied. Paper I discusses and tests the feasible futures and future performance to be considered in attributional LCAs. The results indicate that the environmental impact attributable to a number of selected fuels, as well as the ranking of them, largely depend on assumptions regarding background systems and by-product use. For the assessment of interventions, a consequential approach is applied. Extensive studies of socio–technical change processes contribute insight into relevant cause–effect chains that can be included in environmental assessments of emerging technologies. A comparison between the Swedish and the Dutch innovation systems for renewable fuels reveals the unfolding of dynamics influenced by shared background factors (Paper II). An investigation of the Swedish history of alternative fuels is used in developing a framework for analysing interaction between emerging technological systems (Paper III). Insights into socio–technical change processes are then used to elaborate scenarios for the future development of renewable fuels in Sweden resulting from current policy choices (Paper IV). In a final paper (Paper V), historical and future cause–effect chains are taken into account in a consequential LCA of ethanol of varying origins in Sweden for the 1990–2020 period. It is concluded that for emerging technologies in an early stage of development, the contribution of an intervention to system change may be more important than the direct change in environmental impact. Finally, it is suggested that all aspects of socio–technical change and the resulting environmental impact may not have to be included in quantitative environmental assessments, such as LCA. ‘Environmental assessment’ could very well include a group of parallel studies that illuminate different cause–effect chains resulting in changed environmental impact, and that are part of a society-wide learning process.
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| 4. |
- Hillman, Karl, 1978, et al.
(författare)
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Exploring technology paths: The development of alternative transport fuels in Sweden 2007–2020
- 2008
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Ingår i: Technological Forecasting and Social Change. - : Elsevier BV. - 0040-1625 .- 1873-5509. ; 75:8, s. 1279-1302
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Tidskriftsartikel (refereegranskat)abstract
- By using socio-technical scenarios, we investigate how present policy choices may affect the development of alternative transport fuels in Sweden. One important choice for policy lies in the balance between general tax exemptions stimulating the market for alternative fuels, and funding of research and development more directly promoting new technology. The implications of this choice are illustrated with four diverging development paths until 2020. In the market-oriented scenarios, we illustrate consequences of breaking the dominance of entrenched technologies and demonstrating a growing market potential for alternatives, but also the risks with a large focus on first generation renewable fuels. In the technology-oriented scenarios, we point out the value of keeping variety among niches in this stage of the transition. In conclusion, if policy is implemented without taking the dynamic forces within the system into account, there is a risk that any measure leads the system into a dead end. But if policy strives to balance the development in different parts of the technological system while making use of various prevailing forces of change, a multitude of different efforts can contribute to the development of a more sustainable transport system. © 2008 Elsevier Inc. All rights reserved.
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| 5. |
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| 6. |
- Landin, Per N., et al.
(författare)
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Power Amplifier Behavioral Modeling Performance Comparison of the LSNA and the Modulation-Domain System
- 2008
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Ingår i: 72ND ARFTG MICROWAVE MEASUREMENT SYMPOSIUM - TIME DOMAIN AND FREQUENCY DOMAIN MEASUREMENT. - New York : IEEE. - 9781424422999 ; , s. 73-78, s. 73-78
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Konferensbidrag (refereegranskat)abstract
- The performance of power amplifier behavioral models depends strongly on the performance of the system used to measure the amplifiers. In this study two different systems with nonlinear measurement capability are used to model a commercially available PA. One system is a large-signal network analyzer (LSNA) and the second system is a modulation-domain system (MDS) consisting of a vector signal generator and a vector signal analyzer. The PA was tested with multitone and WCDMA signals and behavioral models were extracted from the measured data. The evaluation criteria normalized mean square error and weighted error spectral power ratio or adjacent channel error power ratio were then computed to compare the performance of the models from the two systems. Cross-validation between the systems, using data from one system to obtain the model and validating its performance with data from the other system, shows that the model performance is mainly affected by the used validation data. Validating the performance of models from the LSNA with data from the MDS indicates that the identified models have almost the same performance as the MDS-identified models, i.e. it does not matter which system is used to identify the models. Cross-validation using a WCDMA-signal and multitone signal from the different systems shows that the normalized mean square error is mainly affected by modeling imperfections introduced by using another signal type. WESPR and ACEPR show a certain difference in performance with somewhat lower values for the MDS. The behavior of the two systems can be explained by different noise levels.
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