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This paper examines the theoretical implications of quantity-discounted transportation rates on the optimum location decision of the firm. It shows that the linearly homogeneous or homothetic production function is not a sufficient condition for the independence between the optimum location and the output level, unless (i) the elasticities of transportation rates with respect to quantity shipped are constant and identical, and (ii) the ratios of marginal products 60 the marginal transportation costs are equal for each input. 相似文献
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In order to carry out strontium (Sr) isotope analysis, glass artefacts from South Asia were sampled with portable laser ablation (pLA), a relatively novel sampling technique that leaves damage invisible to the naked eye. Subsequently, thermal ionization mass spectrometry (TIMS) was used to obtain Sr isotope ratios after sample dissolution and separation. In this study, the goal was twofold: to determine whether the measurements of Sr isotope ratios were impacted by using a portable laser as a sample tool; and to assess the pertinence of using Sr isotope ratios to provenance Indian glass. Despite a deterioration in the precision of the measurement of the Sr isotope ratios for artefacts sampled with pLA compared with the traditional sampling method, the Sr isotope ratios of certain Indian glass are so different that this does not affect their separation but a comparison of data sets obtained using standard methods and pLA might be challenging. 相似文献
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The archaeological record of prehistoric Cyprus is rich, diverse, well-published, and frequently enigmatic. Regarded by many as a bridge between western Asia and the Aegean, Cyprus and its past are frequently seen from scholarly perspectives prevalent in one of those two cultural areas. Its material culture, however, differs radically from that of either area. Apart from the early colonization episodes on the island (perhaps three during the pre-Neolithic and Neolithic), evidence of foreign contact remains limited until the Bronze Age (post-2500 B. C.). This study seeks to present the prehistory of Cyprus from an indigenous perspective, and to examine a series of archaeological problems that foreground Cyprus within its eastern Mediterranean context. The study begins with an overview of time, place, and the nature of fieldwork on the island, continues with a presentation and discussion of several significant issues in Cypriot prehistory (e.g., insularity, colonization, subsistence, regionalism, interaction, social complexity, economic diversity), and concludes with a brief discussion of prospects for the archaeology of Cyprus up to and beyond 2000. 相似文献
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ABSTRACT. The problem of locating a point that is as far as possible from arcs and nodes of a network is investigated. Each arc or node may have a different multiplicative factor (weight) for its distance. A graphical solution approach, as well as a computational algorithm, is presented. 相似文献
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David O. Rafter 《European Planning Studies》1996,4(2):225-236
The concept of sustainability has become a significant consideration in planning in Europe and the US. At both the international and the national level, urban planners and policymakers have developed a package of policies designed to produce sustainable growth and development. In transport, this has been interpreted to mean that we need to increase accessibility while we reduce mobility by shifting trips from automobile to walking, bicycle or public transport modes. Using this criteria, the latest Dublin transport plan has been found to be only partially effective. Similar to many American transport plans, the DTI has opted for the infrastructure‐related sustainability policies and avoided the less popular economic disincentives. 相似文献