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公路建设项目的环保投资分析 总被引:1,自引:0,他引:1
通过调查研究我国部分省市的公路环保投资.对我国公路环保投资的主体、来源、规模结构、使用结构进行了分析.为公路环保投资的决策管理提供参考资料。 相似文献
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Joachim F. Wohlwill 《Coastal management》2013,41(3-4):225-248
Abstract The focus of this paper is theoretical, as well as methodological. It reviews previous studies of visual impact and reports research by the author on people's evaluation of the appropriateness of different man‐made facilities in different coastal‐area contexts and other environments. In this study, subjects were asked to react to slides developed through the use of landscape models and experimental facilities to simulate the appearance of a building in the landscape, while systematically varying the visual relatedness between the two. Specific interest centered on the variable of congruity vs. contrast between the appearance of the building and its landscape context, manipulated by co‐varying the attributes of color and size to create a five‐point scale of contrast/obtrusiveness. The hypothesis was that judgments of appropriateness, and to a lesser extent judgments of liking, would vary inversely with level of contrast. The role of two further variables, the functional significance of the building in its setting, and the character of the setting itself, was also investigated. The author reviews methodological issues involved where subjects respond to visual stimuli for purposes of judging change in visual quality. These methodological issues include: stimulus‐selection and problems of simulation, choice of response measures, and choice of respondents, and the treatment of individual differences. The author calls for development of standardized scales and indices such as “perceptually‐relevant environmental quality indicators.” 相似文献
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Robert A. Kagan 《Coastal management》2013,41(3):313-341
Abstract Seaport expansion often generates tensions between the national interest in efficient transport and local interests in water quality and habitat preservation. The governing American permitting system, however, establishes an extraordinarily cumbersome, legalistic, and costly method for balancing environmental and economic considerations. A case study of the Port of Oakland illustrates the tendency. For four years, plans to find an environmentally acceptable site for dredged material have been stymied by a sequence of inconclusive regulatory and judicial proceedings. Meanwhile, large container ships can enter and leave Oakland harbor only at high tide, and not fully loaded. Despite the absence of any authoritative determination concerning environmental risks, the port was compelled to accede to progressively more expensive disposal methods. Such “adversarial legalism”; is not unique to the Oakland harbor case, but recurs in other policy spheres. It stems from a governmental structure that fragments decision‐making power among many agencies, that constrains regulatory discretion with legal demands for scientific certainty, and that by allowing agency decisions to be challenged readily in court, encourages legalistic defensiveness and extortion rather than compromise. The article concludes with a discussion of the conditions under which regional planning bodies might overcome these centrifugal tendencies. 相似文献
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Angie Fredrickson 《Coastal management》2013,41(3):258-271
Consistent with the policies set forth in the Coastal Zone Management Act, the California Coastal Act seeks to balance the utilization and conservation of coastal resources, taking into account the social and economic needs of the citizens of California. One way the statute pursues this balance is through its provisions for ports. These provisions have functioned as a type of smart growth planning for ports, encouraging densification of existing port districts and possibly averting maritime commercial and industrial sprawl along the California coast. One unintended consequence of the encouraged consolidation of port activities, when combined with the rapid growth in international trade over the last four decades, has been disproportionally large environmental and health impacts on low-income and minority communities surrounding ports. This article examines how the Port of Long Beach's conformance with the California Coastal Act has resulted in ongoing environmental justice concerns. It discusses approaches employed by the Port of Long Beach to reduce environmental justice concerns resulting from significant and unavoidable environmental impacts and offers suggestions for how to address this issue. 相似文献
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介绍祁临高速路堑边坡病害处治中舍弃了传统的刚性防护,而采用的一种新型柔性绿色防护类型。从经济效益、社会效益、施工技术特点等方面论述了这种新型环保防护形式的优越性。该工程坚持环境保护和经济建设同步发展的方针,以护坡、绿化、环保、和谐为主题,围绕以人为本的宗旨,科学设计,使之成新型柔性护坡的典范。 相似文献
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水平隧道火灾通风纵向控制风速的合理确定 总被引:2,自引:0,他引:2
针对2种等宽度、不等高度的水平隧道模型,借助CFD技术分析了环境温度、火灾热释放强度、断面形状对临界风速的影响。选择断面水力高度为特征尺寸,获得2种隧道模型对应的量纲一的临界风速随热释放强度的变化关系,且其与缩尺模型试验及全尺度试验结果相比均具有较好的一致性;并基于CFD模拟结果,分析了Kennedy公式的不足。结果表明,大型隧道火灾通风纵向控制风速的确定过程中应避免使用Kennedy公式计算临界风速。 相似文献
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