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231.
重庆城市地貌图的设计和编制 总被引:5,自引:0,他引:5
本文从设计意图、设计内容和编制方法等方面,总结了重庆城市地貌制图中取得的一些主要经验,探讨了城市地貌图的特点。 相似文献
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Valiya M. Hamza Fernando J.S. Silva Dias 《Physics of the Earth and Planetary Interiors》2005,152(4):223-256
A summary of heat flow data acquired over recent years in several areas in the eastern (Brazil and Paraguay) and western (Bolivia, Chile, Colombia and Ecuador) parts of South American continent are presented. The improvements in the database have allowed numerical representations of heat flow for southeastern and central segments of the Precambrian fold belts in Brazil, Central Andean cordilleras in Chile and Bolivia, Southern Volcanic arc in Peru, Neuquén Province in southwestern Argentina, Chaco basin in Paraguay, Oriente basin in Ecuador and the system of pericratonic basins in north central Colombia. The maps reveal considerable variability in heat flow, not only between the main tectonic units but also within them. The intra-regional variations seem to originate mainly from complexities in local geologic structures while the inter-regional ones seem to point to action of deep-seated tectonic processes. The cordilleran regions are, in general, characterized by relatively high heat flow (>70 mW/m2), compared with the coastal regions to the west and the Pre-cordilleran basins to the east. In the eastern part of the continent, heat flow is low to normal (<60 mW/m2), the exceptions being the Mesozoic rift basins, areas of Cenozoic alkaline intrusions and some isolated belts of overthrust tectonics in the central parts of Brazil. There are indications that heat flow is high in the Patagonian Platform relative to that found in the Brazilian Platform.In addition, polynomial methods were employed for examining large-scale variations of heat flow over the continent. Specifically, a general-purpose least square solution was used to determine the coefficients of up to fourth order in latitude and longitude. Some of the large-scale trends seen in low order polynomial representations seem to be indicative of the nature of deep-seated heat transfer processes. The systematic increase in regional heat flow in the north-south direction is an example. It is considered as the consequence of thermal blanketing effect of the continental segment of the South American lithosphere. Trends seen in higher order polynomials seem to be associated with regional tectonic patterns and subduction-related magmatism. Prominent among these are east-west trending belts of low heat flow in northern Peru and in central Chile, as well as the high heat flow belts in northern Chile, Altiplano of Bolivia and northwestern Argentina. Limitations arising from low data density and uneven geographic distribution warrant higher degree polynomial representations. 相似文献
235.
A MODEL FOR QUANTITATIVELY ESTIMATING SHORT-RANGE PRECIPITATION BASED ON GMS DIGITALIZED CLOUD MAPS—PART Ⅱ:ASSESSMENT OF RESULTS FROM THE MODEL FOR SATELLITE-IMAGE QUANTITATIVELY ESTIMATING PRECIPITATION 下载免费PDF全文
This is Part Ⅱ of this series.It introduces the technique for recognizing MαCS phased properties and its precipitation center or centers by means of dynamic digitalized cloud maps and presents the assessment of the effectiveness of the model proposed in Part Ⅰ as to its fitting and forecasting accuracy. 相似文献
236.
桐柏—信阳一带区域地球化学调查是全国区域化探扫面的一部分。编图中涉及19和20投影带及4个1∶20万图幅的拼接,制图中存在不少技术难题。为了避免2个投影带产生的裂隙坐标不统一,将20带数据转换到19带,然后在高斯—克吕格座标表中查取座标自然值,并计算座标通用值后进行座标展绘,取得了较好的制图效果。 相似文献
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This study provides a procedure for assessing seismic hazardand uncertainties in regions that are characterised by a large non-instrumental earthquakedatabase and a seismic and tectonic behaviour which doesn't allow an evident seismic zonation.This procedure is a synthesis of the non-zoning or non-parametric methodology (using extremevalues distribution functions as proposed by Epstein and Lomnitz, 1966) and the zoning orparametric methodology (using the theorem of total probability as proposed by Cornell, 1968)via a logic tree procedure taking into consideration the advantages offered by each of these.Taking the area which we shall describe as the east coast of Spain and surrounding inland areas,an application was made and a specific logic tree was developed in order to solve the problems anduncertainties related to the evaluation of the seismic hazard using both methodologies. The use of thelogic tree allowed the systematisation of a large number of solutions obtained. A number of relevantresults were obtained which show that in some cases there are great differences in the seismichazard results provided by the non-zoning and the zoning methodologies. In these cases, mean value andstandard deviation of the obtained results provide an intermediate solution to the over-conservativeestimation provided by the non-zoning methodology and the lowest results provided by the zoningmethodology. In other cases results provided by both methodologies are significantly closer.In any case, synthesis among both methodologies gives a wider knowledge of the uncertaintiesassociated with the seismic hazard results. Finally uncertainties increase with the decreaseof the annual probability of exceedence and in sites with a seismic history of large size earthquakes. 相似文献
238.
The seismotectonic environment and seismic activity in Southwest China region were studied based on new data and new results obtained during the Eighth and Ninth Five-Year Plans,the seismic areas and zones and potential seismic source zones were determined.and the relation between seismic activity parameters and ground motion attenuation was determined.Finally the seismic gound motion zoning maps of the Pangxi region was compiled by using the multi-parameter and multi-scheme method. 相似文献
239.
乡村性和乡村旅游吸引力:基于游客感知视角的要素结构辨识和认知机制解析 总被引:1,自引:0,他引:1
在旅游研究领域中,乡村性被普遍认为是乡村旅游的核心吸引力。然而,现有研究基本没有从游客感知视角对乡村性要素结构进行辨识,未能展现游客对乡村旅游吸引力的认知逻辑,也无法体现乡村性和乡村旅游吸引力之间的关系。因此,在游客感知视角下,使用VEP和半结构访谈相结合的质性研究方法,对受访者提供的乡村照片以及相对应的访谈内容进行编码归纳。研究发现:1)乡村性要素可依据游客视觉、听觉、触觉、味-嗅觉和定位系统构建乡村性结构,并可从中归纳出“本底乡村性”和“植入乡村性”两种类型。2)在乡村旅游的过程中,游客在个人主观层面存在“核心—边缘”结构的感知特征,其中“核心乡村性”和“边缘乡村性”两者之间界限模糊,且存在相互转换的可能。3)在游客感知视角下,乡村性和乡村旅游吸引力之间存在“感知系统—乡村性要素—乡村性景观—乡村旅游吸引力”为逻辑主线的认知机制,认为乡村旅游吸引力虽然可以以本底乡村性构成的本底性景观为基础,但同时也是一个复合的结构,由本底乡村性、植入乡村性组合而成的本底性、植入性和融合性景观综合构成,其中尤其不能忽略融合性景观对乡村旅游吸引力的营造作用。 相似文献
240.
以湖南省张谷英村为例,采用开放式问卷、深度访谈和扎根理论方法,构建旅游创新年谱,识别传统村落社区旅游创新的认知基础和认知维度,探究认知重构的影响机制。结果表明:(1)张谷英村由旅游服务创新主导向旅游体验创新主导演化。(2)客体变迁与认知主体学习驱动村民四维认知重构,并通过旅游创新主体多元化以及路径创造推动旅游创新演化。(3)传统村落家的体验将深层次化,真实性将得到重构;自组织旅游创新演化将成为传统村落旅游地演化的重要力量;社区旅游创新既是村民对家的重塑和美化,也是传统村落文化的传承和创造。 相似文献