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61.
In the past decade Tobler has provided an innovative cartographic presentation of migration flows. The central theme of this research has been to utilize detailed migration data to reveal the underlying structures of migration flows. Even though the analyses are not explanatory models of migration exchanges, the application of these techniques to migration flows over time and across different spatial scales provides a visual generalization of often extremely complex flows. The application of his techniques at two spatial scales for the Netherlands illustrates both the strengths and weaknesses of migration force fields for the analysis of migration. 相似文献
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Patten BM 《Journal of the history of the neurosciences》1992,1(1):3-14
Every time a physician conducts a neurological examination the process continues a biomedical search for understanding the nervous system which is as ancient as the earliest civilizations in human history. Most of the modern neurological examination evolved in a short time span, between 1850 and 1914, but the origins of neurology as a medical quest for knowledge date to the first evolution of urban life, in the valleys of the Euphrates and the Nile. This paper reviews this history in two chronological segments: part 1 up to 1850 and part 2 the subsequent period. 相似文献
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Spatial compactness has been proposed as a suitable criterion for assessing whether electoral boundaries reflect partisan interests. Although several different measures of spatial compactness have been developed, only limited efforts have been made to compare and evaluate them in the context of electoral redistricting. This paper assesses alternative spatial compactness measures and applies conceptually appealing measures to the provincial ridings proposed by British Columbia's Royal Commission on Electoral Boundaries (1988). 相似文献
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Three rare Himyaritic coins found in the territory of the ancient Hadramawt kingdom are published for the first time. Two of the coins bear the name of the king,'Amdan Bayyin, while the third has the name of Tha'ran Ya'ub. 相似文献
70.
This paper is concerned with the products of a number of Neolithic quarries in highland Britain. It investigates the claim that the scale of axe distribution was partly the result of social factors which resulted in these artefacts gaining an added value in areas remote from their sources. One case study considers the sequence of production in Cumbria, in relation to the tensile strength of the rock quarried in different parts of the region. It shows that these considerations had only a limited influence over the choice of stone source and the scale on which it was worked. A second study compares the tensile strength of the main raw materials used for making non-flint axes with the extent to which these sources were actually exploited. Again there is only a limited relationship between the two, suggesting that social factors may indeed have been important. 相似文献