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991.
路径描述是日常生活中常见的地理空间信息应用方式,涉及到自然语言与地图语言的表达及转换关系。本文采用认知实验的方法,对自然语言的路径描述及其认知过程进行分析,研究了路径认知与表达上所涉及的空间关系,总结了利用自然语言表达地图空间信息的规律和习惯用法。 相似文献
992.
本文提出了利用空间数据库和GIS技术整理分析方志、古籍的研究方法,结合《中国古代重大自然灾害和异常年表总集》中记载的各种自然灾害信息,采用面向对象的Geodatabase数据模型,建立了中国全区域的,多朝代的,多自然灾害要素的,带有地理特征的关系型数据库,实现了数据的统一描述与管理,并根据专题数据制作了单一灾害要素、多种灾害要素的专题地图,可视化分析了历史自然灾害的时空分异,最后将地图进行网络发布以实现数据共享。结果表明GIS有利于方志、古籍的数字化整理与分析,实现了以信息技术保护、传播和有效的利用方志资料。 相似文献
993.
MATTHEW C. LaFEVOR 《Geographical review》2012,102(2):202-224
The discovery, extraction, and monopolistic control of key natural resources was a priority of New Spain's colonial administration. Managing the region's abundant resources, however, often proved difficult for the Spanish Crown. Human and environmental challenges impeded protoindustrial growth and development, and monopolistic control of resources often met resistance. In this article I examine these processes in the context of New Spain's little‐known monopoly on sulphur—a yellow, powdery mineral the Crown jealously guarded as its own. Sulphur was critical for gunpowder and explosives production, yet the Crown often failed to produce enough of it to meet the growing demand by its military and the silver blast‐mining industry. Colonial documents reveal administrators’ attempts to improve sulphur production through reform measures, which included advising sulphur miners on how to discover sulphur deposits and, eventually, how to develop their mines. Efforts to improve sulphur production were moderately successful, although the process was messy and inefficient. 相似文献
994.
《The Journal of geography》2012,111(4-5):142-153
Abstract This article demonstrates geography's role as an integrative discipline and its utility in connecting students to the world around them. A case study links China's demography and its geopolitics to the lives of U.S. students. The relationship of China's population pressures to its resulting economic growth, need for economic resources, and geopolitical efforts are examined using the concepts and holistic capabilities that are the academic strength of geography. 相似文献
995.
以福建省永安市麻岭村9 hm2的典型天然阔叶林为试验研究对象,应用系统抽样方法,分别200 m×100m、100 m×100 m、100 m×50 m和100 m×25 m四种抽样密度,探讨林分主要测树因子的抽样估计精度.结果表明:试验的天然阔叶林分平均树高、平均胸径、平均密度与平均单位面积蓄积量等主要测树因子的估计精度都分别要求达到70%以上、75%以上、80%以上和85%以上的最小抽样密度分别是100 m×100 m、100 m × 50 m、100m×50 m和10 0m×25 m.试验的天然阔叶林分胸径Ⅲ组林木蓄积量的估计精度分别要求达到70%以上、75%以上和80%以上的最小抽样密度分别是100 m×50 m、100 m×25 m和100 m×25 m. 相似文献
996.
997.
历史时期中国重大自然灾害时空分异特征(英文) 总被引:4,自引:0,他引:4
Based on historical documents and records this paper analyzes the characteristics of frequency and distribution of major disasters that took place in the history of China. The findings show that occurrences of different types of disasters varied and spatial pattern at provincial level are significantly different as well. The results also indicate that there is a strong relationship between type of disasters and spatial distribution and that the spatial pattern of losses was not the same as that of the frequency. The reasons are: (1) the hazard-formative environments which, to a large extent, determine the spatial pattern of the disasters are significantly different; (2) the losses caused by natural disasters were closely related to the concentration of economy and population. Number of deaths was usually large in areas where agriculture, culture and business were relatively developed. The spatial pattern of disaster losses is an evitable result of uneven economic development in the history of China. 相似文献
998.
The paper presents the prediction of total energy production and consumption in all provinces and autonomous regions as well as determination of the variation of gravity center of the energy production, consumption and total discharge of industrial waste water, gas and residue of China via the energy and environmental quality data from 1978 to 2009 in China by use of GM(1,1) model and gravity center model, based on which the paper also analyzes the dynamic variation in regional difference in energy production, consumption and environmental quality and their relationship. The results are shown as follows. 1) The gravity center of energy production is gradually moving southwestward and the entire movement track approxi-mates to linear variation, indicating that the difference of energy production between the east and west, south and north is narrowing to a certain extent, with the difference between the east and the west narrowing faster than that between the south and the north. 2) The gravity center of energy consumption is moving southwestward with perceptible fluctuation, of which the gravity center position from 2000 to 2005 was relatively stable, with slight annual position variation, indicating that the growth rates of all provinces and autonomous regions are basically the same. 3) The gravity center of the total discharge of industrial waste water, gas and residue is characterized by fluctuation in longitude and latitude to a certain degree. But, it shows a southwestward trend on the whole. 4) There are common ground and discrepancy in the variation track of the gravity center of the energy production & consumption of China, and the comparative analysis of the gravity center of them and that of total discharge of industrial waste water, gas and residue shows that the environmental quality level is closely associated with the energy production and consumption (especially the energy consumption), indicating that the environment cost in economy of energy is higher in China. 相似文献
999.
1000.