Master-Arbeit Univ. St. Gallen, 2007.

Master-Arbeit Univ. St. Gallen, 2007.

Bachelor-Arbeit Univ. St. Gallen, 2007.

Master-Arbeit Univ. St. Gallen, 2008.

No Abstract Provided

No description available.

This dissertation is based on three essays in operations and supply chain management. In essay 1, we study an operations scheduling problem in a complex manufacturing system, most notably, semiconductor manufacturing. In particular, we study the scheduling problem of minimizing total weighted tardiness on parallel non-identical batch processing machines. We formulate the (primal) problem as a nonlinear integer programming model. Moreover, we prove that the primal problem can be solved exactly by solving a corresponding dual problem with nonlinear relaxation. Since both the primal and the dual problems are NP-hard, we propose to use genetic algorithms, based on random keys and multiple choice encodings, to heuristically solve them. We found that the genetic algorithms consistently outperform a standard mathematical programming package in terms of solutions and computation times. We also found that for small scale problem instances, the multiple choice genetic algorithm outperforms the random keys genetic algorithm, while for medium and large scale problem instances, the random keys genetic algorithm outperforms the multiple choice genetic algorithm. In essay 2, we study a monopolist firm offering successive versions of a durable good (e.g., software) that improves over time. The firm decides the time between successive introductions as well as price. In turn, consumers strategically decide whether to purchase or wait for a later version. We model and analyze three alternative strategies for offering successive product versions: the partial-, continuous-, and no-updates policies. We first consider the firm's profit maximizing policy assuming a homogeneous market and subsequently address consumers with heterogeneous product valuations. Our analytic model's simple structure and results highlight the important tradeoff between price and release timing for products with successive versions. In essay 3, we study the effect of time series structure of customer demand models on the value of information sharing within a supply chain. We contribute to the literature by incorporating a nonlinear demand model based on exponential disturbances, coupled with temporal heteroscedasticity, which captures more complex patterns in the demand process. We examine the conditions under which information sharing is valuable. / 10000-01-01

Kyoto University (京都大学) / 0048 / 新制・課程博士 / 博士(工学) / 甲第13812号 / 工博第2916号 / 新制||工||1431(附属図書館) / 26028 / UT51-2008-C728 / 京都大学大学院工学研究科機械理工学専攻 / (主査)教授 椹木 哲夫, 教授 吉村 允孝, 教授 松原 厚 / 学位規則第4条第1項該当

No description available.

Bakgrund och problematisering Under 90-talet flyttade många företag sin produktion till lågkostnadsländer långt bort för att minska sina produktionskostnader och därmed öka konkurrensfördelarna. Nu menar forskare att denna trend börjat vända, och företag väljer att flytta tillbaka sin produktion till hemlandet eller i ett närliggande lågkostnadsland då det visat sig att totalkostnaden inte blev lägre. En produktion i eller nära hemlandet kan resultera i minskad totalkostnad, minskade risker och ett ökat värde för kunden. Valet av produktionsland kan också starkt influeras av företagets hållbarhetsarbete. Majoriteten av forskningen är fokuserad kring jämförandet av Sverige med ett lågkostnadsland i Asien men väldigt lite forskning finns som jämför Sverige med ett lågkostnadsland i Europa. Syfte och metod Syftet för studien är att jämföra strategierna inshoring och nearshoring genom att undersöka svenska hållbara mikroföretags val av produktionsland. För att jämföra strategierna kommer vi undersöka dessa utifrån faktorerna kostnad, risk och värde. Det empiriska materialet samlas in med hjälp av semistrukturerade intervjuer med företag som har sin produktion i antingen Sverige eller Portugal. Resultatet kommer sedan att analyseras och kopplas till den teoretiska referensramen kring Supply Chain Management, hållbarhet och de tre faktorerna ovan för att kunna besvara syftet. Resultat och slutsats Efter att den empiriska datan analyserats kom vi fram till att företagen till en hög grad delade forskarnas syn på att en produktion i Sverige på många sätt var mer kostnads effektiv, mindre riskfylld och ökade värdet för konsumenterna då varumärket och produkterna sågs mer hållbara. Däremot märkte vi också att design spelade en stor roll in på vilket produktionsland man väljer, något som litteraturen inte tagit upp. Vi konstaterade att det inte finns en sourcingstrategi som ansågs vara bäst, utan företagets storlek, framtidsplaner, produktdesign och materialanvändning istället påverkar vilket produktionsland som är mest lämpligt. / Background and problematisation During the 1990’s many companies moved their production to remote low cost countries to reduce their production costs and create an increased competitive advantage. Research has now shown that this trend is reversing and companies are now starting to move their production to their home country or a close by low cost country due to the revelation that the total cost did not increase. Placing the production in or near the home country can result in a lower total cost, reduced risks and an increase of value to the consumer. The production location choice can also strongly be influenced by the companies’ sustainability work. The majority of research is focused around the comparison of Sweden and a low cost country in Asia but very little research has been done comparing Sweden and Europe. Purpose and method The purpose of the study is to compare the strategies inshoring and nearshoring by investigating Swedish sustainable micro companies’ choice of production location. To compare the strategies we will evaluate these through the factors cost, risk and value. The empirical material will be collected through semi-structured interviews with companies producing in either Sweden or Portugal. The result will then be analysed and connected to the theoretical framework around Supply Chain Management, sustainability and the three factors above to answer our research questions. Result and conclusion After the empirical data had been analysed we saw that the companies more or less shared there searchers’ views on that a production in Sweden in many ways was more cost effective, less prone to risks and increased the value to the consumers due to the brand being perceived as more sustainable. Also the design of the product played a big part in the choice of production location, something the literature did not bring up. Our conclusion was that none of the sourcing strategies were considered the best, but the size of the company, product design and the choice of material affected which production country that was deemed the most suitable. This thesis is written in Swedish.