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ABSTRACT. In a simple urban model, where the only spatial distinction made is between center and suburb, we introduce a uniform distribution of preferences for land. Under a logarithmic utility function, we examine how the location and consumption decisions of individuals differ in consequence of their different preferences for land. Comparative statics indicate that the qualitative response of the city at equilibrium to changes in per capita income and transportation cost is not affected by the introduction of such heterogeneity. Possible extensions are also briefly discussed.  相似文献   
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"This paper examines the mechanism and extent of urban concentration using a two-sector growth model. The cause of urbanization is sought in the existence of urban scale economies. Assuming that temporary production decisions are concerned with optimal labor inputs and that profit incomes are reinvested according to relative profitability, the model shows persistent tendency for urban concentration and the transition of the economy from unlimited to limited labor supply. A simple example suggests that urban concentration is more likely than rural expansion with urban contraction."  相似文献   
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Non‐invasive materials characterisation of reconstructed statues of Emperor Qin Shihuang's Terracotta Army has revealed distinct micro‐geochemical patterning within the clay paste used in their manufacture. The significance of this is explored in terms of the production sequence, logistics and supply‐chain management involved in the construction of this enormous funerary assemblage. Of particular interest is a compositional distinction between figures marked with the names ‘Gong’ (宫) and ‘Xianyang’ (咸阳). These seem to represent the products of two workshops involved in the supply of ceramic objects for this ambitious, large‐scale building project undertaken by the Qin Empire during the third century bce .  相似文献   
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Bayesian statistics has now demonstrated its strong utility in archaeology, specifically through software that conditions radiocarbon data. Only recently has this technology been applied within Maya archaeology, however, in part because the Maya calendar provides a much greater resolution in dating archaeological events than is possible with radiocarbon data. The Long Count in particular allows for the assignment of some events relative to each other, accurate to the day. In this paper, a new approach is presented to incorporate robust records of both in the same Bayesian analysis through the OxCal software. The results do call for a reconsideration of the earliest radiocarbon studies in the Maya area from the 1960s, as well as the latest attempts to corroborate the currently popular calendar correlation known as the GMT. This new study demonstrates the value of the approach and corroborates the 1σ accuracy of the GMT, while at the same time opening up the possibility of revision by 20 or more years.  相似文献   
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The Akko 1 shipwreck was an Egyptian armed vessel, built at the beginning of the 19th century. A wooden saw handle and a box containing iron nails and two split pins were discovered towards the stern. Given their function, location and context, these were part of the ship's carpenter's tools and accessories. A methodology was developed for conducting systematic metallurgical analysis in order to understand the manufacturing process of the surviving ironwork items, as well as to enlarge our knowledge regarding ironworking technologies during the early 19th century. Such methodology may assist in the future understanding of the technological evolution of similar wrought‐iron objects. The results demonstrated that the artefacts have a wrought‐iron heterogeneous microstructure and were manufactured by hot‐working prior to surface hardening by pack carburization.  相似文献   
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