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溶地下水脆弱性评价“二元法”及其在重庆金佛山的应用 总被引：12，自引：4，他引：8
岩溶地下水脆弱性评价是基于保护岩溶含水层从而有效地管理和利用地下水提出的有效方法和手段。我国西南岩溶区极大多数地区缺少应有的地下水保护带,地下水比较容易受到污染。本文论述了一种脆弱性的评价的简单方法— —基于径流特征和覆盖层厚度的二元法,并利用该法对重庆金佛山典型岩溶区进行了地下水脆弱性评价。结果表明,药池坝洼地和生态石林区脆弱性较高。究其原因,尽管药池坝洼地底部土壤层覆盖较厚,但存在地表径流集中排向落水洞,生态石林分布区地表裂隙、溶沟发育,可直接接受雨水入渗,因而污染物极易通过降雨和地表径流过程进入含水层。这一方法输入数据量小,对岩溶含水层普遍适用,为地下水资源可持续利用和土地利用管理提供了强有力的工具。 相似文献
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压性盆地（最典型的是前陆盆地）层序地层学是目前层序地层学的一个重要研究领域和方向。压性盆地在地层填充和层序叠置样式等诸多方面都表现出与被动大陆边缘经典层序地层样式以及我国东部伸展性陆相断陷盆地层序样式的显著区别。通过各种地质、钻井、测井和地球物理等资料的综合分析,建立了焉耆盆地博湖坳陷前陆盆地层序地层格架,综合分析前陆盆地构造背景下层序结构的二元性特征,并在此基础上建立起来博湖坳陷侏罗系的层序发育模式,分析了二元性层序发育机理,并指出在油气勘探中,应以层序底部的岩性油气藏或构造-岩性混合油气藏为主要勘探目标。 相似文献
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Aharon Kellerman 《The Professional geographer》1987,39(3):267-274
Integration in human geography is achieved through multidimensional research or by the study of a variety of aspects of a whole. Giddens's structuration theory provides a new theoretical framework for integrative study in human geography in its attempt to connect individuals and societies, context and composition, time and space. Integrative studies in geography have focused on space (regional geography), time (historical geography) and society (time-geography). Structurationist analysis in geography can put society, space, or society and space at its focus. Thrift's spatial structurationist theory may lead to a new theoretically-based regionalism. On the other hand, integration at one level or between several elements may entail disintegration, at another level or element respectively. 相似文献
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《Urban geography》2013,34(8):684-704
This paper examines a social movement among affluent homeowners in Los Angeles. It argues that the social movement is highly institutionalized and durable, and that it has achieved many important citywide and statewide goals during the past 20 years. The paper further argues that this social movement should rightly be considered a stable branch of the urban elite along with local business and local government. However, the homeowners movement pursues a fundamentally different sociospatial agenda than either local business or local government, and those differing agendas suggest the absence of a unified governing regime in the city. The paper examines the structure, agenda, and political alliances of the movement through the case study of the debate surrounding the spatial and political reorganization of the City of Los Angeles, the most salient element of which is the possibility of San Fernando Valley secession. 相似文献
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《The Professional geographer》2013,65(3):267-271
Integration in human geography is achieved through multidimensional research or by the study of a variety of aspects of a whole. Giddens's structuration theory provides a new theoretical framework for integrative study in human geography in its attempt to connect individuals and societies, context and composition, time and space. Integrative studies in geography have focused on space (regional geography), time (historical geography) and society (time-geography). Structurationist analysis in geography can put society, space, or society and space at its focus. Thrift's spatial structurationist theory may lead to a new theoretically-based regionalism. On the other hand, integration at one level or between several elements may entail disintegration, at another level or element respectively. 相似文献
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论述量子远程通讯的最新成就很可能意味着自然界存在超光速的信息联系，狭义相对论又面临新的考验，若考虑虚数“i”的作用，狭义相对论可与物质的超光速运动相容，而且不违反因果律，即使自然界存在超光速的物质运行也不可能动摇狭义相对论，建议设计实验测量德布罗意波的相速度并深入研究波粒二象性。 相似文献
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吴文璐 《成都信息工程学院学报》2011,26(3):277-282
余代数为各种各样的模态逻辑提供一致的语义框架.Lutz Schr？der证明了任意自函子的余代数类都有一个rank-1的公理化.反过来,每一个rank-1的模态逻辑都有一个可靠的、强完备的余代数语义.另一方面,Clemens Kupke等提出模态逻辑可以描述成布尔代数上的自函子,并基于对偶理论研究余代数逻辑的可靠完备性.通过对偶理论重新证明了rank-1的模态逻辑都是余代数的,并且证明通过对偶理论构造出来的函子和Schr？der所构造的函子是等价的. 相似文献
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众所周知,消费者行为理论是微观经济学研究的重要内容之一.消费者在收入有限的情况下,面对众多的商品如何进行选择,使其尽可能得到大的＂满足＂;在保持某一效用水平不变时,面对众多的商品如何进行选择,使其总支出最小.基于这两个问题,利用数学规划中的对偶理论对其进行经济学分析,得出了若干相关结论.从而拓宽了数学规划理论的应用领域,对消费者行为的理性选择具有重要的理论指导意义. 相似文献