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The technology of Roman harbours 总被引:2,自引:0,他引:2
John Peter Oleson 《International Journal of Nautical Archaeology》1988,17(2):147-157
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This article reports a generalised and systematic approach to the thermoluminescence (TL) dating of samples which suffer from anomalous fading. We hypothesise that the TL signal from each mineral phase is composed of a stable and an unstable portion. The decay of the unstable TL is accelerated thermally, until only stable TL remains. The dating is then carried out on this stable signal. The results, on four known-age, coeval samples, exhibiting gross anomalous fading (25-50% loss over a few days), indicate that many, if not all, samples may successfully be dated with this approach. 相似文献
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ABSTRACT This paper examines the role of the structure of transportation rates in the Weber-Moses triangle model. It shows that, in Zeigler's analysis, the appearance of the price elasticities of demand for inputs actually vanish by a simple application of the envelope theorem. Applying comparative statics analysis, we show when transportation rates are a function of quantity and distance, the assumptions that the production function is homogeneous of degree one and the transportation rates elasticities with respect to quantity and distance are constant are not sufficient to insure that the optimum location is independent of the level of output. This result is significantly different from that obtained by either Miller and Jensen or Zeigler. 相似文献
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John Overton 《Oceania; a journal devoted to the study of the native peoples of Australia, New Guinea, and the Islands of the Pacific》1988,58(3):193-211
Village societies in rural Fiji have often been studied in terms of a dichotomy between traditional village communalism and independent galala individualism. This was especially so in the 1960s, at a time when government efforts to promote individualist Fijian agriculture led to the creation of a number of resettlement schemes based on the peasant model. Social scientists hailed the galala movement as a fundamental and progressive process of change in Fijian society. However, recent evidence and the demise of regulations which institutionalised galala point to the present lack of distinction between galala and villagers. Indeed, there is considerable confusion within some villages over how galala should be defined and it seems to be much more a matter of spatial location of residence than any attitudinal or economic break with communalism. 相似文献
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The soluble and exchangeable ions for a soil profile from the Roonka archaeological site. Lower Murray Basin, South Australia, are compared with the total elemental content of the soils. Since the chemical composition of post-mortem ionic substitution phases and secondary minerals in archaeological bone will depend on the availability of ions to the soil solution under field conditions, it is suggested that models addressing diagenesis in bone employ soluble and exchangeable ions rather than total elemental soil data. 相似文献