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161.
美国"阳光带"的崛起对中国西部城市化战略的启示   总被引:1,自引:0,他引:1  
美国西部开发以城市化为先导,中国西部大开发本质上也是西部城市化。西部大开发战略应以城市为中心组织与落实。本文通过透视美国“阳光带”城市崛起的历史,尤其是产业集群的成功经验,提出中国西部城市化战略实施中应将培育地方产业集群作为推动城市化的重要战略方式和地方重要的公共政策工具。  相似文献   
162.
基于受限汉语的GIS路径重建研究   总被引:4,自引:1,他引:4  
刘瑜  高勇  林报嘉  邬伦 《遥感学报》2004,8(4):323-330
主要研究基于自然语言 (汉语 )的GIS路径重建问题 ,通过分析带有路径表述信息的汉语文本 ,建立了汉语的NLRP句法模型 ,它是由带有空间语义的动作以及作为动作对象的地理要素构成的集合。考虑到自然语言理解实现的需求 ,论文基于NLRP句法模型定义了受限汉语的NLRP文法 ,在此基础上 ,描述了路径重建算法PRA ,并探讨了算法实现中由于空间认知原因带来的不确定性问题以及其解决方案。最后 ,基于该算法进行了相关实例研究 ,从而验证了该算法的正确性  相似文献   
163.
The contribution of areal precipitation of the catchment from Cuntan to Yichang (Three Gorges area) to eight flood peaks of the Upper Yangtze River (the upper reaches of the Yangtze River) is diagnosed for 1998 flood season. A rainfall-runoff model is employed to simulate runoffs of-this catchment. Comparison of observed and simulated runoffs shows that the rainfall-runoff model has a good capability to simulate the runoff over a large-scale river and the results describe the eight flood peaks very well. Forecast results are closely associated with the sensitivity of the model to rainfall and the calibration processes. Other reasons leading to simulation errors are further discussed.  相似文献   
164.
Introduction The Xiuyan earthquake(MS=5.4)on Nov.29,1999,occurred between Hushan town and Pi-anling town at the southeast end of the aftershocks of Haicheng earthquake(MS=7.3).These two earthquakes′sequences are highly similar in the way that the foreshocks are very frequent,focal mechanisms of the main shocks are about the same and fault strikes are approximately in the same direction.It is important to study these earthquakes for further research on seismogenesis to fore-cast earthquake…  相似文献   
165.
Introduction Ready and Renkin (1971) were the first to make the research on anisotropy problems in magnetotellurics (MT). The progress in the research is not evident because it is more complex and difficult than isotropic problems. Now, the one-dimensional (1D) anisotropy problems in MT have been well solved, while for the two-dimensional (2D) cases, the numerical solutions have only been obtained for some particular conditions (Ready and Renkin, 1975). As to the three-dimensional (3D) ani…  相似文献   
166.
Introduction Data mining (SHAO and YU, 2003) is a new kind of technique developed with database and artificial intelligence in recent years, which processes the data in the database to abstract the im- plied and pre-unknown, but potentially useful information and knowledge from large amounts of incomplete, noisy, blurring and stochastic data. For data mining, data purging is an important link beforehand that includes eliminating noise, making up lost domain, and deleting ineffective data, as…  相似文献   
167.
Succeeding to multiply collisions of different blocks in Late Paleozoic[1―5], complex intracontinental structural deformation occurred in the Tianshan area during Mesozoic-Cenozoic[6―16], which controlled coeval basin-range evolution and resulted in intensive modi- fication and adjustment of the Paleozoic oil-gas reser- voirs[17―19]. The Kuqa Depression is a secendary struc- tural unit of the Tarim basin, in which Mesozoic- Ce- nozoic deposits occur in thickness of 6000―7000 m. The Kuq…  相似文献   
168.
Changes in the spatial scale of Beijing UHI and urban development   总被引:2,自引:1,他引:2  
The seasonal and interannual variations of Beijing urban heat island (UHI) are investigated in this paper using the temperature data from 1960 to 2000 at 20 meteorological stations in the Beijing region, and then the relationship between the intensity and spatial scale of UHI and Beijing urbanization indices is analyzed and discussed. Main conclusions are the followings. First, Beijing UHI shows obvious seasonal variations, and it is strongest in winter, next in spring and autumn, and least in summer. The seasonal variation of the UHI mainly occurs in the urban area. The UHI intensity at the center of Beijing is more than 0.8℃ in winter, and only 0.5℃ in summer. Second, the intensity of Beijing HUI exhibits a clear interannual warming trend with its mean growth rate (MGR) being 0.3088℃/10 a. The MGR of HUI is largest in winter, next in spring and autumn, and least in summer, and the urban temperature increase makes a major contribution to the growth of HUI intensity. Third, since the Reform and Opening, the urbanization indices have grown several ten times or even one hundred times, the intensity of HUI has increased dramatically, and its spatial scale also expanded distinctively along with the expansion of urban architectural complexes. Fourth, the interannual variation of urbanization indices is very similar with that of HUI intensity, and their linear correlation coefficients are significant at a more than 0.001 confidence level.  相似文献   
169.
Based on the analysis of newly collected data of plate tectonics, distribution of active faults and crustal deformation, the Taiwan area is divided into two seismic regions and six seismic belts. Then, correlation fractal dimensions of all the regions and belts are calculated, and the fractal characteristics of hypocenteral distribution can be quantitatively analyzed. Finally, multifractal dimensions Dq and f(α) are calculated by using the earthquake catalog of the past 11 years in the Taiwan area. This study indicates that (1) there exists a favorable corresponding relationship between spatial images of seismic activity described with correlation fractal dimension analysis and tectonic settings; (2) the temporal structure of earthquakes is not single but multifractal fractal, and the pattern of Dq variation with time is a good indicator for predicting strong earthquake events.  相似文献   
170.
翁泉沟含铀硼铁矿床综合开发利用研究与对策   总被引:1,自引:1,他引:1  
翁泉沟含铀硼铁矿中硼(B2O3)储量约占我国总储量的一半,矿床经勘探后一直没有很好得到利用。在综合利用资料积累与地质研究基础上,认为影响矿床利用的因素主要为矿石分解状况。研究认为矿床中硼镁铁矿-磁铁矿和硼镁石-磁铁矿两种主要类型矿石中绝大部分为可利用的变质后期热液作用产生的硼镁石-磁铁矿型矿石。这种热液作用形成的矿石是有规律可寻的。为达到综合利用的目的,有必要按不同类型矿石重新圈定矿体,根据不同矿体中硼镁铁矿分解率指标,选择两种不同综合利用方案。  相似文献   
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