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41.
水资源空间分布模型及GIS分析应用 总被引:4,自引:0,他引:4
随着社会生产力的持续发展,人类活动范围不断拓宽,不可避免地影响着流域自然水循环过程。因此,在对流域水资源状况进行定量描述时,必须综合考虑自然、人文二元要素的影响。本文选取了近年来水资源短缺和水环境恶化问题严重的京津冀地区为研究对象。根据区内的自然条件和社会发展情况,选取了对水资源空间分布有明显影响的因素。其中距河流远近因素体现了对水资源的开发利用能力;坡度因素代表了土壤的持水能力,对径流和地下水有影响;而土地利用类型因素反映了土壤下垫面的水文特性。通过AHP方法确定上述影响因素的权重,建立水资源空间分布测算模型。根据模型将按流域单元统计的水资源总量数据展布到公里格网上,得到了水资源空间分布结果。最后,通过对空间化水资源数据的分析,剖析了当地的水资源状况,结合"一轴三带"的规划分区思想,对如何进行区域水资源可持续开发利用提出了参考意见。 相似文献
42.
近年来我国城市地理学主要研究领域的新进展 总被引:16,自引:0,他引:16
本文对改革开放以来中国城市地理学研究的新进展作了综述,尤其注重新领域的进展和主要观点的概括。本文涉及的主要领域包括:(1)城市化研究;(2)城市发展方针的研究;(3)城市体系研究;(4)城市内部空间结构研究。最后,在研究展望中作者指出,在社会主义市场经济体制下,应开展城市土地和住房以及国际大都市的研究。 相似文献
43.
44.
Many tens of severe earthquake damage patterns were revealed at the ancient city of Ayla. The seismic deformation patterns
are of various types, including systematic tilting of walls, systematic shifting and rotation of wall fragments and individual
stones, arch deformations and joints crossing two or more stones. Features of later repair, supporting walls and secondary
use of building stones suggest that the damage patterns can be explained by two historical devastating earthquakes: (I) revealed
in the constructions built during the late Rashidun period (644–656 A.D.); (II) revealed in the structures restored and/or
built during the Fatimid period (1050–1116 A.D.). The maximum observed intensity of both earthquakes at the studied site was
not less than IX (EMS98 scale). The sources of the seismic events were probably the Dead Sea Transform and Wadi Araba Faults
that cross the site obliquely. The last 1995 Nuweiba earthquake with maximum observed intensity VIII has also left its clear
traces in the excavated ancient Ayla buildings. The severity of the destruction was significantly increased because of site
effects. 相似文献
45.
Michael C. Ewers 《GeoJournal》2007,68(2-3):119-130
Urban areas compete with one another for people, goods, capital, ideas and other inputs of economic activity. Under the rubric
of globalization, instead of only maintaining or improving the initial stock of assets in a city, the power of a place to
attract outside flows of economic activity from elsewhere is increasingly important to economic development. Similarly, global
or world cities are characterized as the command and control points through which these global economic flows operate. In
response to the heightened mobility of highly-skilled labor across national borders, research has begun to examine the role
of international human capital as an economic flow. This paper will examine the role of places in determining where the highly-skilled
go in the global economy by viewing global city command and control functions as requiring unique labor flows. By reviewing
the evidence found in the literature, we can better understand the potential for urban areas to compete for highly-skilled
labor in the global economy. Known indicators of place attractiveness are assessed to examine the relationship between the
economic trajectories of cities and their labor requirements. Cities are situated between firms and states as the key place-based
actors which influence the mobility of highly-skilled labor. Finally, the paper also examines measurement issues and methodological
problems in creating indices of world cities as well as explores possibilities for new research. 相似文献
46.
全球城市理论与中国的国际城市建设 总被引:2,自引:0,他引:2
全球城市是多因素作用的结果,研究范式由20世纪70年代的马克思主义政治经济学向全球与地区相互作用的范式转换。全球城市体系的划分从单一指标向经济与文化结合的多指标方向发展。但如何选取指标,如何进行指标的测量,如何确定各指标的权重分配以及如何采集城市间相互作用的数据与资料,都是全球城市研究要面对的重要问题。中国的全球城市建设要从全球城市体系的等级、位序规律出发,根据社会经济发展的实际,要有步骤、有目标、分阶段,稳步推进,逐步提升城市发展的层次,促进城市国际化的步伐,建设中国的国际城市。 相似文献
47.
In this paper an intervening opportunities model with spatial dominance is developed. The usual assumption in spatial theory
is that decision makers are influenced not just by the size of a destination or distance but by these two factors in combination, that is, spatial dominance. Decision-makers will have more knowledge about, and clearly perceive destinations that exert
the greatest amount of spatial dominance on their origins, just as they would primate cities. Thus destinations are ranked
in terms of the spatial dominance calculated for each destination. Empirical verification of the model utilizes state-to-state
migration flow data for the US. Calibration results compare favourably with the traditional intervening opportunities model
and the production constrained gravity model.
Received: 7 October 1999/Accepted: 15 June 2000 相似文献
48.
49.
本文根据探矿权人的具体情况,阐述了引资勘查的重要性;结合现行法律,法规,论述了利用探矿权引进外资勘查项目的特殊性和复杂性,并就西部大开发和招商引资的要求,对贵州省的探矿权招商引资政策和法规出台,促进我省的矿产资源勘查开发,提出一些建议。 相似文献
50.
The binational cities of Dover and Calais and their region 总被引:2,自引:0,他引:2
Odile Heddebaut 《GeoJournal》2001,54(1):61-71
This paper analyses the question of cities that are localised at each part of an international border. We take as an example
the two cities of Dover and Calais and look at if they can be considered as binational cities, because they have been recently
connected by a tunnel, the ‘fixed link’, and because since 1993, the inner state borders of the European Union have disappeared.
It determines firstly if these two towns have been brought closer by the construction of the Channel tunnel and if specific
ties are linking these two towns. The article scrutinizes actions taken under INTERREG funds under the general framework of
the creation of the ‘Transmanche Region’ and its extension towards a Euroregion to sort out these two cities joint involvement.
Finally, it checks if this new area could lead to cross-border activity either for work or tourism and leisure purposes that
could conduct the cities of Dover and Calais toward a new type of relationship, premises of a binational city.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献