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Edward Jarvis in 1850 first demonstrated that admission rates to mental hospitals decrease with increasing residential distance, a relationship known today as “Jarvis's Law.” His original data are presented, mapped, and examined by regression analysis to better understand spatial and temporal patterns of mid-19th century mental hospital utilization. Distance substantially affected admission rates to a radius of about 60 miles from the institution in Massachusetts; and there was strong distance decay in the other states examined. For all twelve states, there was a positive association between age of the hospitals and admission rates, which also decreased with increasing residential distance.  相似文献   

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This article shows how the random walk drainage network simulation model might be used as a class teaching exercise. Practical instructions about running the model are given and the results discussed. A source of directional bias in the resulting simulated drainage patterns is identified and given an interpretation in the terms of the model. Three points of educational value concerning the model are emphasized in conclusion.  相似文献   

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Bedrock forms of etch origin result from the interaction of groundwaters and bedrock at the weathering front at the base of the regolith. They are significant for general theories of landscape and landform genesis because they are azonal with respect both to climate and lithology. Two stages of etch form development are recognized: one involves weathering and the formation of a regolith; the second consists of stripping of the regolith and the exposure of the bedrock forms. Although etch forms have been recognized for some two centuries, the concept of etching as a process of landform development has been neglected, particularly in North America.  相似文献   

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《The Journal of geography》2012,111(9):555-560
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Figures from the 1970 Soviet Census provide an abundance of information on population changes in the U.S.S.R. Of special note is the process of urbanization and a noticeable concentration of urban growth in the hitherto largely rural zones of western Russia. A large map of urban places in 1970, designed primarily for classroom use, accompanies the text (see inside back cover). The map utilizes a special stippled-sphere technique to allow a three-dimensional effect without half-tone reproduction.  相似文献   

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Religion continues to play an important role in the public and private lives of Americans. Therefore, a reexamination of U.S. religious regions is necessary in light of the rapid demographic changes that have occurred in the past few decades. This article presents a new regionalization of religion in the United States for 1980 and 2000, produced using multivariate cluster analysis. Comparing this new regionalization with earlier attempts, it demonstrates that religious regions continue to exist today and have undergone various levels of stability and change. Furthermore, religious regions continue to be relevant because they provide scholars with a method for identifying and characterizing the societal context in which individual religious communities function.  相似文献   

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美国占领菲律宾伊始就带有明显的地缘政治因素。二战后,美国出于"冷战"的需要,把菲律宾变成亚洲"遏制"战略中的一个重要地缘前哨。随着冷战的结束,美在菲律宾的军事基地被取消,美-菲同盟关系也陷入谷底。21世纪之初,全球经济重心开始向亚太地区转移,美国也加快实施战略东移,开始重新审视其东亚地缘战略。近几年,美菲不断加强军事合作,大搞联合军演,借口所谓的南海航行自由,极力在南海搅局,其中明显带有制衡中国的因素。在美国急于实施"亚太再平衡"战略的背景下,菲律宾为美国在东亚地区的一个重要地缘支点。然而,菲新政府积极改善对华关系,一定程度上影响到了美-菲同盟关系的发展。  相似文献   

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"This report presents the results and assumptions of a set of projections of the population of the USSR, 1979-2025. Trends in population size and age-sex composition as well as fertility, mortality, and emigration are discussed.... The projections show that the population of the USSR will grow throughout the period to 2025. The working age population will grow very slowly for at least the next 10 years, and will not recapture the rapid growth experienced in the 1970s. The pension-age population will double in size between 1980 and 2025."  相似文献   

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What is a hilly city, and which cities are hilliest? This study outlines a basket of methods for quantifying the differential hilliness of U.S. cities. We rank the 100 largest cities in the contiguous United States, using a selection of eight methods to evaluate their comparative hilliness. We then reflect on how four key “modes of encounter” with terrain shape human perceptions of urban hilliness: visual, pedestrian, automotive, and imagined/conceptual. Varying priorities among these different modes of encounter shape which of our indices may best correlate with lay understandings of urban hilliness or particular policy problems. We conclude with implications of this work for contemporary geographic scholarship and suggestions for further research, particularly with regard to the political and economic effects of hilliness.  相似文献   

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