This study presents the results of using common two or three-parameter "default" distributions in place of "best fit distributions" in simulations of serial production lines with finite buffers and blocking. The default distributions used instead of the best-fit distribution are chosen such that they are non-negative, unbounded, and can match either the first two moments or the first three moments of the collected data. Furthermore, the selected default distributions must be commonly available (or easily constructed from) distributions in simulation software packages. The lognormal is used as the two-parameter distribution to match the first two moments of the data. The two-level hyper-exponential and three-parameter lognormal are used as three-parameter distributions to match the first three moments of the data. To test the use of these distributions in simulations, production lines have been separated into two major classes: automated and manual. In automated systems the workstations have fixed processing times and random time between failures, and random repair times. In manual systems, the workstations are reliable but have random processing times. Results for both classes of lines show that the differences in throughput from simulations using best-fit distributions and two parameter lognormal is small in some cases and can be reduced in others by matching the first three moments of the data. Also, different scenarios are identified which lead to higher differences in throughput when using a two-parameter default distribution. / Graduation date: 2004

Zugl.: Chemnitz, Techn. Univ., Diss., 2004 u.d.T.: Stewens, Michael: Supply Chain Management

The objective of the thesis was to construct a deterministic single year, farm planning model that would enable vegetable producers to select an optimal farm plan from among alternative crops and crop production methods so as to maximize farm income consistent with technological and resource constraints and other goals. The model was to be readily adaptable to a wide range of commercial vegetable farmers in Canada but sufficiently flexible to be adaptable to the particular situation of a specific farm. A multiperiod linear programming model was built and validated through its application to a large commercial vegetable farm. The relevant theory of the firm was reviewed with special attention made to the theory's application to vegetable farms. The structure of a linear programming problem was discussed and related to the theory of the firm and vegetable farms. Special emphasis was placed on the problem of modeling the machinery used in vegetable production. The work of agricultural engineers was examined to determine the technological relationships involved in machine operation. Other crop budgeting models which involved the construction of similar planning models for a different sector of the agricultural community, especially the Purdue Crop Budgeting Models were reviewed. The model constructed was able to deal with machinery constraints by building a number of machine operating activities and tractor transfers so that the time constraint for a particular job would consist of any subset of the predefined set of time periods. Standard coefficients were prepared based on engineering formulae for fuel consumption and repair and maintenance costs for tractors. All inputs in the model except repair and maintenance costs were in physical units. This made it necessary to build several different types of purchasing or renting activities but facilitates the interpretation of data and the use of the model in a large number of different situations. The model was validated through its application to a large commercial vegetable farm in British Columbia. The model was run in simulation mode by forcing the model to follow the farm's 1974 crop plan and altering yields and prices to yields and prices that actually occured in that year. In this manner the reliability of the cost coefficients of the input data and the relationships between resources could be evaluated and compared with the results recorded in the farm's CANFARM records. The model was run in optimization mode with expected 1976 prices and yields to demonstrate the use of the model in selecting an optimal farm plan. A total of six plans were prepared based on alternate market and risk constraints and yields. These were compared with the plan selected by the farmer without the aid of the model. A detailed report on one of the farm plans v/as also prepared. / Land and Food Systems, Faculty of / Graduate

No description available.

The paper studies the impact of a diversification vs. a core-competence oriented strategy using an agent-based simulation model. The aim of the paper is twofold: first, we analyze whether agent-based models are a viable tool for analyzing questions related to corporate strategy. We show that standard results from the strategy literature can indeed be reproduced and refined by using this type of models. Second, the agent-based model allows us to formulate more precise hypotheses and more precisely delineate the scope of situations in which standard results from the strategy literature apply. For the problem of diversification analyzed in this paper, the results from the agent-based simulation lead to the conclusion that in addition to environmental dynamics, overall market size is also an important factor, which was not considered in the previous literature. / Series: Working Papers SFB "Adaptive Information Systems and Modelling in Economics and Management Science"

Typescript, etc. / Digitized by Kansas Correctional Industries

No description available.

Zugl: Bayreuth, Univ., Diss., 2004

Univ., Diss.--St. Gallen, 2003.

M.Comm. (Strategic Management) / The turbulent and swiftly changing business environment assigns very big requirements and challenges to managers of all enterprises. Because of the current political and constitutional process of reform, local authorities find themselves on the verge of dramatical structural change. Traditionally local authorities operated in a relatively predictable and inert environment. The turbulent and swiftly changing environment, together with the expected structural changes, assign unprecedented demands and challenges to the managers of local government. To enable managers to handle these requirements and challenges to the optimal benefit of their residents and businessmen, the advancement of strategic management is of utmost importance. This study is directed at the distinguishing of potential requirements and challenges that could be assigned to managers in local government and to local government's pressing need of strategic management. A discussion of the use of computerbased management simulation as support to strategic mana~ment training in local government is included in the study. The central purpose of the study is to distinguish different applications of management simulation as an aid to the promotion of strategic management in local government and to indicate the value thereof. Management simulation can successfully be used to provide managers in local authority with simulated experience of the practical application of strategic management theory. Managers get the opportunity of strategically directing a simulated local authority and in this way they can make decisions without the need to fear for the consequences of erroneous decisions. There is no doubt that management simulation can make a worthwhile contribution to the advancement of strategic management in local government.