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51.
地震动在强度和频率等方面均具有非平稳特性,导致多跨桥梁的动力响应非常复杂.为了研究多跨连续桥梁在多点地震动激励下的反应,首先提出了评价多点地震动非平稳性的3个指标:幅值绝对值的标准差、方向离散度和穿零率.根据桥梁多点激励运动方程的特点,阐述了广义振型参与系数矩阵的意义,及其与传统振型参与系数矩阵的联系和区别.根据多点地...  相似文献   
52.
自然资源利用权从产生的途径上看应属于特许物权,从内容和功能上看应属于准用益物权,两种物权属性并不相互排斥。自然资源利用权的双重物权属性符合环境保护的价值取向和价值选择。  相似文献   
53.
Abstract: A public opinion survey was carried out in Montana to ascertain if the public identifies a level of benthic (bottom‐attached) river and stream algae that is undesirable for recreation. The survey had two parts; an On‐River survey and a By‐Mail survey. The On‐River survey was conducted via 44 trips randomly scheduled throughout the state during which recreators were interviewed in‐person at the stream. Selection of stream segments and survey dates/times was based on known, statewide recreational use patterns. By‐Mail survey forms were sent to 2,000 individuals randomly selected from Montana’s Centralized Voter File (CVF) available from the Montana Secretary of State. The CVF was current through 2004 and represented over 85% of the state’s eligible voting population. In both surveys, eight randomly ordered photographs depicting varying levels of stream benthic algae were presented, and participants were asked if the algae level shown was desirable or undesirable for recreation. Survey form design, selection of photographs, and pretesting followed acceptable protocols that limited unintentional bias through survey execution. There were 433 returned forms (389 complete) for the By‐Mail survey, while the On‐River survey documented 563 interviews. In both surveys, as benthic algal chlorophyll a (Chl a) levels increased, desirability for recreation decreased. (Other measures of benthic algae biomass are presented as well.) For the public majority, mean benthic Chl a levels ≥200 mg/m2 were determined to be undesirable for recreation, whereas mean levels ≤150 mg Chl a/m2 were found to be desirable. Error rates were within the survey’s statistical design criteria (≤5%). The largest potential error source was nonresponse in the By‐Mail survey; however, the population represented by nonrespondents would have to exhibit profoundly different perceptions of river and stream algae to meaningfully alter the results. Results support earlier work in the literature suggesting 150 mg Chl a/m2 represents a benthic algae nuisance threshold.  相似文献   
54.
认真落实科学发展观,以科学发展观统领工会工作,必须体现在党对工会工作的要求上,体现在准确全面履行好工会的职责上,从而充分发挥工会在支持改革开放、促进经济发展、推动社会进步中的积极作用。  相似文献   
55.
从规划内容与目标、规划方法及方案实施和评估3方面对太湖近20年水污染物控制历程进行综合分析,认为太湖水污染物控制正处面源污染、生活污染及新型污染问题凸显且更难处理,更为广泛的利益相关者和科研队伍积极参与的转型期.这种变化将导致污染治理面临更难应付的动态性和复杂性,使得当前以环境容量为总量为指导通过自上而下分配排污量和削减量的控制方案面临极大挑战.结合太湖水污染现状,通过与现行治理方法在管理假设、适合对象、协调管理手段、管理目标、规划方法、公众参与程度以及规划的优劣势等方面的比较发现,适应性管理可以积极有效应对由于环境趋势和管理协调对象变化所带来的系统不确定性和复杂性,将是一个积极有效的补充方法.同时,本文基于适应性管理提出了太湖水环境污染物排放控制体系的构建框架,突出适应性管理平台、科学研究及公众与基层单位参与在污染物控制中的重要作用.  相似文献   
56.
Currently, China is facing critical problems regarding the management of municipal solid waste (MSW). The failure of existing pilot programs in implementing MSW source-separated collection highlights the need to analyze the factors significantly influencing public participation in this activity. To this end, a comprehensive analysis of MSW source-separated collection in Guilin, which is representative of wider areas located in inland China and with a GDP around the national average, was conducted. The research consisted of in-person interviews involving a questionnaire and theoretical analyses in terms of public perception, public awareness, public attitude, and willingness to pay. The analytical results identify the status of waste source-separated collection and influencing factors in implementation, and provides exercisable suggestions for decision makers in both China and more generally in industrializing countries to design promotion programs and education campaigns.  相似文献   
57.
Floress, Kristin, Jean C. Mangun, Mae A. Davenport, and Karl W.J. Williard, 2009. Constraints to Watershed Planning: Group Structure and Process. Journal of the American Water Resources Association (JAWRA) 45(6):1352‐1360. Abstract: The roles that agencies and other partners play in collaborative watershed management are not always clearly identified. Key factors contributing to group‐level outcomes in watershed groups include both structural and procedural elements. Structural elements include membership systems, project partners, and funding, while procedural elements include leadership, shared vision, and mission development. The current research reports on a case study conducted with a Midwestern watershed group that received Clean Water Act Section 319 funds to undertake a watershed planning process. Data come from focus groups, interviews, public comments, and meeting observation, and were analyzed using grounded theory. Findings of this study indicate that homogenous skill set, discord over group and partner roles, and failed problem identification contributed to the organizational inertia experienced by the watershed group. Implications of this research for groups receiving 319 funds are provided.  相似文献   
58.
The Toxics Release Inventory (TRI) created by the 1986 Emergency Planning and Community Right-to-Know Act initially received limited attention. During the early years of its implementation, the TRI has become the basis for a national experiment in voluntaristic problem solving among citizens and industry, but that process of environmental democracy hinges on citizens' ability to actually acquire, understand, and apply the new data on industrial toxic emissions. A national study of TRI-using organizations in the public and private sectors reveals that effective citizen access depends in part on the efforts of intermediary public interest groups to bridge individual needs and right-to-know data. Although the TRI has had early success as a supplement to conventional command and control regulation, questions exist about the extent to which state and federal government should or must provide special efforts to make environmental information access work for citizens.  相似文献   
59.
Initial decision analysis (IDA) is a microcomputer based decision-making technique that is organized so that a rational, step-by-step, procedure can be followed to use existing knowledge to develop resource policies. The IDA process provides a systematic way for participants to define their own problem and to explore jointly alternative solutions. IDA is particularly suited to resolving complex problems involving many groups with conflicting interests. IDA is illustrated with data from the US Forest Service's Draft Environmental Impact Statement for the 1985 to 2030 Resource Planning Act Program for the United States. Four policy options are evaluated: maximization of timber production, of grazing, and of wilderness, and a dominant use policy that concentrates timber management on productive sites. Policies were evaluated using a new mathematical satisficing procedure. Mathematical satisficing of simulated policy consequences showed that, for selected performance standards, current RPA policies are superior to the four alternative policies examined.  相似文献   
60.
Colorado, USA, developed the Joint Review Process (CJRP) in 1978 to coordinate the application and review of permits required for major development projects. Since then, the state has used the process on over 20 projects. This study examined whether the CJRP has achieved its primary goals—enhanced coordination of agencies, enhanced public participation, and strengthened communication between agencies and project sponsors— and several related secondary goals. The success of the process was measured through a survey of 54 key people who had been directly involved with the process. Those surveyed included federal and state agency staff, local agency managers, corporate officers, private consultants, and environmental leaders. All groups, with one exception, agreed that the process achieved its primary goals and that it should be retained. Environmental leaders were neutral about whether the process enhanced public participation and about retaining the process. The report concludes with a review of recommended improvements to and applications of the CJRP.  相似文献   
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