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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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《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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"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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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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Does perception match reality when people judge the flatness of large areas, such as U.S. states? The authors conducted a geomorphometric analysis of the contiguous United States, employing publicly available geographic software, Shuttle Radar Topography Mission (SRTM) elevation data, and a new algorithm for measuring flatness. Each 90‐meter cell was categorized as not flat, flat, flatter, or flattest, and each state was measured in terms of percentage flat, flatter, and flattest as well as absolute area in each category. Ultimately, forty‐eight states plus the District of Columbia were mapped and ranked according to these values. Keywords: flatness, U.S. states, slope, Kansas, Florida.  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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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 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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Increases in U.S. income inequality are driven primarily by rapidly rising incomes of the top 1%. At the national scale, rising inequality is associated with negative consequences for economic growth and stability, a range of social problems and declining social mobility. To date, there is no or little work on the geography of the top 1% and their impact on the cities they inhabit. Using individual income data from the U.S. Census, the paper offers the first detailed analysis of the spatial distribution of the top 1% in the United States. The paper makes use of the range of socio-demographic variables attached to individual records to illustrate that the large majority of the top 1% lives in large cities and that women and ethnic minorities are largely excluded from membership in the top 1%. The widening gap between incomes at the top and bottom will thus lead to increasing gender and ethnic income inequalities. Exploratory analysis of the impact of the top 1% on the bottom 99% suggests that cities with large shares of the top 1% are characterized by higher levels of skill polarization, higher labour force participation rates and lower unemployment rates for those with little formal education and higher median incomes for the better educated. However, the paper shows that higher incomes are outstripped by higher housing costs indicating that any potential advantage trickling down from the top 1% to the bottom 99% is eroded by higher living costs. Preliminary analysis also suggests that cities with a higher share of the top 1% tend to be more segregated with potential implications for the supply, quality, access to and distribution of public local services.  相似文献   

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"Despite the widespread interest in the changing geographies of national migration regimes, it is somewhat remarkable that no widely accepted measure of the spatial concentration or focus exhibited by such geographies has emerged. We examine four of the most popular indices of inequality in this paper and contrast their performance as measures of spatial focus. Adopting the coefficient of variation as our preferred alternative, we go on to examine the spatial focus of aggregate interstate migration steams in the U.S. over time. Then we consider disaggregations of the migration streams by age, race and nativity, and examine the role of states as national redistributors of these same subpopulations."  相似文献   

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