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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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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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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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"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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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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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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一项旅游活动的发展与流行需要多种内部和外部条件的支撑。中国的露营活动还处于发展的初期,目前还没有成体系的露营地建设,也没有相应的发展和管理措施。自发的露营活动很不规范,容易带来一系列社会问题。为了促进我国露营活动的健康发展,露营地的成体系和规范建设,论文从多个方面分析了美国露营活动流行的原因,及其对我国露营活动开展的启示。首先分析美国的早期移民从东海岸向西海岸探险过程中,对露营活动的形成和促进作用;在露营活动过程中,参与者如何从活动中获得休闲娱乐、磨炼意志、知识学习、生存经验积累等多方面的收益,特别是对青少年的教育和锻炼作用。其次分析美国露营地建设种类和各种基础设施建设,以及露营者行为管理、露营地管理等各种管理措施对有序开展露营活动的支撑作用。再次从多种外部因素分析露营活动流行的原因,主要包括:地理气候等自然因素,高速公路系统、信息发布、生活品供应等各种基础设施因素,假期制度、生活与传统习惯和公共道德等各种社会文化因素等。最后在综合分析美国露营活动流行原因的基础上,提出我国如何结合自身国情开展露营活动。  相似文献   

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The production of liquid fuels from coal will very likely become an important part of the hydrocarbon energy mix of the future, provided that technical and environmental obstacles are overcome economically. The coal industry should be able to handle a coal-to-liquids (CTL) industry of modest size, using 60–70 million short tons or 54–64 million metric tonnes of coal per annum, without premature depletion of the country’s coal reserves. However, attempts to use CTL technology to replace all petroleum imports would deplete the nation’s coal reserves by the end of the century.  相似文献   

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Palynological analyses were completed for the A and B horizons of a forested Mollic Hapludalf to determine type, amount, and distribution of pollen and spores within the soil solum. Hypotheses regarding the origin of pollen and the mechanisms of its movement within soil bodies are also advanced. Pollen downwash within the mineral soil seems to be very slow and confined to the uppermost porous and most homogenized part of the solum. The predominance of non-arboreal pollen at depth was believed to be a result of deposition with the loess parent material. High arboreal pollen frequencies in the upper horizons coupled with increases in non-arboreal types at depth indicate gradual ongoing mixing from the present vegetation into the soil.  相似文献   

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Fifty retail chains with more than 70,000 U.S. store locations were placed into a cluster analysis to group together similar chains based on lifestyle segmentation composition of store trade areas. Five distinct cluster groups emerged. The objective was to analyze whether the geographic exposure to various lifestyles is aligned with the value platform of each retailer. Competitors were also analyzed along the lines of group membership. Although not all competitors were in the same groups, category killers generally located near higher income segments, whereas value retailers and chains that feature off-price merchandise generally located near customers with more modest incomes.  相似文献   

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This article analyzes how far U.S. companies locate subsidiaries in need of highly skilled staff in state locations in Germany that have a high ranking of creativity. Such locations should provide an especially attractive location for certain “creative” staff, which should be of special interest to U.S. companies in need of highly skilled staff. Analyzing U.S. companies that were established since the year 2000 and with more than fifty staff, we find support for our propositions that nonmanufacturing and organizationally higher rank subsidiaries with a need for urban infrastructure and connectedness are located in creative states in Germany.  相似文献   

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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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American geographers have tended to ignore the effects of war upon the economic development of the United States. Using the values of real and personal property given in the U.S. Censuses between 1850 and 1890, the impact of the Civil War and the duration of that impact can be measured relatively. The Civil War not only destroyed the capital resources of the South, but also appears to have led to the predominance of New York City in American economic life.  相似文献   

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