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131.
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M.G.A. WILSON 《Geographical Research》1984,22(2):202-220
The article seeks to enhance understanding of post-transitional demographic change by examining the working out at the local level of the macro-scale societal processes underpinning the recent cyclic oscillation in Australian reproductive behaviour. Variations in urban marital and overall fertility between 1966 and 1971 and between 1971 and 1976 are described and analysed. In general, inter-urban variability in both measures diminished greatly, as did the explanatory power of ecological differentials, suggesting widespread acceptance of the small family norm throughout the study-area. While the process of convergence was continuous for marital fertility, structural changes contributed to later divergence of overall fertility levels, in accordance with Alonso's cyclical model of change. The current low level of residual inter-urban variability suggests that little more may be gained from analyses of this type. 相似文献
133.
Archaeologists, along with other Quaternary researchers, seldom rely upon a single radiocarbon determination to provide an estimate of the age of the phenomenon which is the object of their study. There is an evident need for an explicitly formulated procedure for comparing sets of radiocarbon determinations from the same and from adjacent strata or sites, and for combining these where statistical and archaeological criteria indicate that this combination is warranted. The present contribution provides explicit modelling for a series of recommended procedures, a critique of previous methods, and paradigms for application of the recommended procedures. 相似文献
134.
Among the manifestations of radioactive decay which can be etched to optical visibility on the surface of mica are tracks from nuclei recoiling from alpha emission, called ‘alpha-recoil tracks’. If, beforeetching, the mica is heated to temperatures of the order of 600°C, all evidence of these tracks is annealed from muscovite mica in a few minutes. Alpha activity observed on mica from pot sherds, from stones surrounding fire places, from fire pits, and fired daub may constitute an alpha-recoil track clock which started at the moment of the last firing of the artifacts. 相似文献
135.
Robert G. Reynolds 《Geographical analysis》1978,10(1):31-46
Models of both primate and hunter-gatherer decision-making systems are developed and their relative abilities potentially to detect certain classes of spatial distributions within a standardized environment are compared. It is demonstrated that in situations where language facilitates the pooling of information between individuals within a hunter-gatherer group, the group minimally need only to pool information with one central decision maker in order potentially to recognize all possible spatial distributions within a limited environment. On this basis alone, we would theoretically expect the presence of one-leader groups to be a fairly ubiquitous phenomenon among hunter-gatherers. 相似文献
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