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ABSTRACT. Real variable analysis has een used to great benefit in a variety of classical problems in location theory. In this paper we explore basic complex variable techniques in one formulation of the obnoxious location problem. A general definition of center points is first given and used to formulate several alternate versions of the obnoxious location problem. A logarithmic transformation is then used to demonstrate some equivalences between these families of distinct location problems (defined via center points). A prototype logarithmic potential function which results from this formulation is then investigated, and it is demonstrated that the extremal solutions with this objective reside on the boundary of its domain of definition. An application using zero- and one-dimensional centers is discussed, and a generalization to the spatial obnoxious problem is also briefly examined. We define a zero-dimensional center as a critical point of the logarithmic potential function, and it is shown that these centers are equivalent to the solutions of the Complex Moment Problem. 相似文献
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Thomas Junker 《Berichte zur Wissenschaftsgeschichte》1993,16(2):163-164
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Traditional infrastructure evaluation focuses primarily on technical criteria, such as the completion of a designated, interconnected system of facilities or a particular project's capacity to reduce costs borne by suppliers or end users. In the contemporary policymaking environment, however, nontechnical criteria are often of great importance in determining the success or failure of a particular infrastructure enterprise. Institutional considerations, for example, can often delay the implementation of a project or undermine its effectiveness. This paper examines the importance of non-technical criteria in infrastructure evaluation through a case study of the implementation of a major highway investment program in advanced communication and control technologies, known as intelligent vehicle -highway systems (IVHS). The case study focuses on the role of institutional issues as well as environmental issues, in the implementation of IVHS in the US. surface transportation system. The case emphasizes, first, the significance of institutional and environmental issues, and second, mechanisms for evaluating these issues in the context of a major infrastructure investment program. 相似文献
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