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81.
82.
《The Professional geographer》1988,40(1):106-116
software reviews are in this article BMDP/PC CONCEPTS COMPUTERIZED ATLAS EVALUATION OF ALTERNATE PROPOSALS (EAP) EXTRA: EXPRESS TRANSIT ANALYSIS MATC CAD MOTORS TRANSPORTATION PACKAGE PCMAP: Thematic Mapping Software for the IBM Personal Computer, Version 2.3 PLACE TRANPLAN . US-ATLAS 相似文献
83.
通过论述汉字信息在地图信息中的重要地位,说明开发地名数字化系统的必要性;并且通过分析汉字的“音、形、义”的结构特征,阐明了地名数字化系统的继承性、层次性、稳定性和开放性。从而说明开发地名数字化系统的艰巨性。 相似文献
84.
An investigation of analysis of variance as a tool for exploring regional differences in strong ground motions 总被引:2,自引:1,他引:1
The statistical technique known as analysis of variance is applied to a large set of European strong-motion data to investigate whether strong ground motions show a regional dependence. This question is important when selecting strong-motion records for the derivation of ground motion prediction equations and also when choosing strong-motion records from one geographical region for design purposes in another. Five regions with much strong-motion data (the Caucasus region, central Italy, Friuli, Greece and south Iceland) are investigated here. For the magnitude and distance range where there are overlapping data from the five areas (2.50 Ms 5.50, 0 d 35 km) and consequently analysis of variance can be performed, there is little evidence for a regional dependence of ground motions. There is a lack of data from moderate and large magnitude earthquakes (Ms > 5.5) so analysis of variance cannot be performed there. Since there is uncertainty regarding scaling ground motions from small to large magnitudes whether ground motions from large earthquakes are significantly different in different parts of Europe is not known. Analysis of variance has the ability to complement other techniques for the assessment of regional dependence of ground motions. 相似文献
85.
根据表层土、深层土的采样研究资料,获取了江西某蔬菜基地的土壤主要重金属元素基准值,分析了5种重金属元素在该区表层土中的分布、分配及相关特点,分析了元素的迁移特征。对该蔬菜基地的土壤重金属污染现状作了初步评价,并提出了合理调整的相关建议。研究发现,该蔬菜基地表层土(耕作土层)中Cd、Hg、Pb存在明显的积聚现象。局部地段土壤中已超出了农业部颁发的无公害蔬菜产地以及绿色食品产地土壤环境质量标准,成了"不安全生产区"。同时发现区内重金属含量本底值并不高,重金属的污染积蓄主要与人类生产活动有关,可能来源于长期不合理的施肥与喷药。 相似文献
86.
For more than a century, hand‐pulled rickshaws have been a prominent part of Calcutta's cityscape. Under the veil of modernization, progress, and globalization, however, the government of West Bengal State declared that rickshaws cause traffic congestion and constitute an exploitative use of human labor. Yet, despite the government‐imposed ban, rickshaws continue to ply the streets of central Calcutta. Based on interviews with rickshaw owners, operators, public officials, and local residents, we examine the cultural politics surrounding rickshaw pulling in Calcutta. This article shows that the rickshaw wallahs (pullers), who operate as part of the informal economy, provide an expansive range of services not limited to transportation. Indeed, the rickshaw wallahs form an integral part of Calcutta's social fabric, having made a place for themselves by facilitating social interaction and challenging hegemonic ideas and practices about who belongs where. 相似文献
87.
《The Journal of geography》2012,111(6):253-265
Abstract This article explores the interplay between geographic concepts and geographers' Web site design. The concepts—place, site, and situation—provide the context for reconsidering current metaphors dominating the rhetoric of cyberspace. Challenging the predominant metaphor of cyberspace as path or highway, we draw on the work of French phenomenologist Merleau-Ponty and on the work of phenomeno-logically oriented geographers to propose the figure/ground structure of cyberplace in contrast to the void of cyberspace. For the absolute freedom of unlimited space we suggest the depth and breadth of world. If geographers succeed at creating Web sites informed by disciplinary concepts, Web site design itself can help to reconceive geographic concepts. Two virtual field-trips offer the opportunity to demonstrate the interaction of a reconceived notion of place and the design of graphical interfaces. The article discovers possibilities for enhancing the value of geographic Web sites. Three design strategies—geographic context, duration, and nonlinearity—are recommended as a result of this investigation. 相似文献
88.
《The Journal of geography》2012,111(2):49-60
Abstract The extant literature on place location learning resolves in varying degrees that place location knowledge (PLK) is deficient in the United States and abroad. This is particularly true for younger school-attending age groups. This study has three main aims: to investigate the validity of that claim in regard to secondary-level students in Dublin by testing their PLK; to assess what characteristics of tested place locations render some sites more visible in students' eyes than others; and to investigate statistically what traits of the respondents shape their PLK. The implications of these findings on geographic education and future research are also discussed. 相似文献
89.
《The Journal of geography》2012,111(3):113-118
Abstract Mental image and place-preference maps of college students in Florida were created through a two-part lesson. The patterns revealed by these maps were linked to students' life experiences, census data on migration and income, and similar studies conducted in other states. Students prefer states with established migration links to Florida and better income/job opportunities. Because the maps could not be created without their input, students were wholly engaged in a lesson that uses concepts in population geography and cartography to fulfill several national geography standards. 相似文献
90.
1993年中国开始从原油输出国变为原油输入国,到2010年,中国的原油进口依赖度高达53%。原油进口来源国的社会经济稳定性、原油运输线路的安全性影响到中国原油进口的安全性。本文根据ITIRI的综合国际贸易投资风险指数和原油运输线路的安全性,设计了中国从其主要原油进口来源国进口原油的风险指数。然后分析了中国各省级行政区对原油进口消费的依赖度,中国六个大区石化工业和八个石油化工基地对进口原油的依赖程度。从而分析了它们对进口原油风险的敏感度。本研究的结论是:第一,中国重要的原油进口来源国比较集中,且集中在社会经济不十分稳定的国家。第二,原油进口风险对沿海地区经济的影响远高于对内陆地区的影响。第三,沪宁杭、琼粤闽和长江中游石化基地是受原油进口风险影响最大的三个基地。根据这些结论,本文提出两方面建议:第一,建议中国原油进口来源与运输方式尽量多元化,以规避风险。第二,中国原油战略储备基地应考虑对原油进口风险敏感度大的地区。 相似文献