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Pey-Chun Chen Pierre Hansen Brigitte Jaumard Hoang Tuy 《Journal of regional science》1992,32(4):467-486
ABSTRACT. Weber's problem consists of locating a facility in the plane in such a way that the weighted sum of Euclidean distances to n given points be minimum. The case where some weights are positive and some are negative is shown to be a d.-c. program (i.e., a global optimization problem with both the objective function and constraint functions written as differences of convex functions), reducible to a problem of concave minimization over a convex set. The reduced problem is then solved by outer-approximation and vertex enumeration. Moreover, locational constraints can be taken into account by combining the previous algorithm with an enumerative procedure on the set of feasible regions. Finally, the algorithm is extended to solve the case where obnoxiousness of the facility is assumed to have exponential decay. Computational experience with n up to 1000 is described. 相似文献
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Zone pricing consists in determining simultaneously several delivered prices together with the zones where these prices apply. A model and algorithm are proposed to determine optimal facility locations, prices, tariff-zones, and market areas in order to maximize the firm's profit under zone pricing. The resulting nonlinear mixed-integer program is tackled by projecting the objective function on the price space, solving repeatedly uncapacitated facility location problems for fixed values of the prices. The implicit profit function so defined is optimized by branch-and-bound. Computational results are reported. 相似文献
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Birgitta Roeck Hansen 《Geografiska annaler. Series B, Human geography》1998,80(4):187-201
Cadastral maps from the 17th and 18th centuries of villages in southwest Finland and Ostrobothnia have been used in this study to map the variations in land organisation that existed before the first enclosure ( storskiftet ). Settlement structure and land division in particular were found to vary regionally, a fact that can be explained by topographical circumstances but also by the different historical background of the historical provinces. The aim was to distinguish between the cultural influences on the use and ownership of land from Sweden (the west) and Finland (the east) respectively. Through the Swedish colonisation of Finland a feudal social organisation was introduced which affected village organisation all over the investigated area but to a varying degree, resulting in several types of settlements from planned villages with regular strip parcelling to villages developed through piecemeal colonisation and with an unsystematic division of the land. 相似文献
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Ulla Lund Hansen 《Norwegian Archaeological Review》2013,46(1-2):155-158
Bente Magnus: Krosshaugfunnet. Et fors?k på kronologisk og stilhistorisk plassering i 5. årh. (The Krosshaug find. An attempt at a chronological and stylistic placing within the 5th century). Stavanger Museums Skrifter 9. Stavanger 1975. 159 Pages, 68 Figs. English summary. 相似文献
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