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131.
防洪物资储备决策方法初探   总被引:2,自引:1,他引:1  
姚令侃  汤家发  杨明 《灾害学》2001,16(1):29-34
根据防洪抢险物资储备属于一种信息不全型决策问题的特点,本文提出了一种用于确定每年防灾物资准备量概率排序决策模型,并以孙不河流泥石流灾害预报火灾决策为例进行说明。  相似文献   
132.
Conservation strategies aimed at reducing threats to biodiversity can have significant implications for multiple sectors in a socioeconomic system, but these cobenefits are often poorly understood. For example, many of the threats to native species also impede agricultural production, yet agriculture is typically perceived as in competition with conservation objectives. Although a comprehensive, multiobjective decision analysis is usually beyond the scope and capacity of conservation decision makers, failing to incorporate key socioeconomic costs and benefits into conservation decision-making processes can result in missed opportunities for diversifying outcomes and creating cost-sharing multisectoral partnerships. We devised a straightforward and readily interpretable approach to incorporate cobenefits into a threat-management prioritization approach. We used it to analyze the agricultural cobenefits of implementing 9 invasive animal management strategies designed to ensure the persistence of 148 threatened species across Australia's Lake Eyre Basin over 50 years. A structured elicitation process with 24 participants (scientists, land managers, agriculturalists, and other stakeholders) was used to collect information on each strategy, including costs, technical and social feasibility, benefits to native threatened species, and cobenefits to agricultural production systems. The costs of targeted invasive animal management to save threatened species across the basin (AU$33 million/year) outweighed the overall benefits to the agricultural industry (estimated AU$226 million/year). The return on investment for these management strategies varied substantially when agricultural cobenefits were considered alongside threatened species benefits and showed synergies and challenges. Our approach demonstrates the value of incorporating cobenefits of conservation actions into cost-effectiveness analyses to guide potential investment and partnerships and to diversify implementation pathways.  相似文献   
133.
134.
CAF涡凹气浮系统-CASS工艺处理 造纸中段废水   总被引:1,自引:0,他引:1  
本文针对造纸中段废水短纤维含量高及可溶性COD占有较大比例的水质特征 ,提出了CAF涡凹气浮系统—周期循环活性污泥法串联污水处理工艺。该工艺具有占地少、投资省、运行效果好、操作管理方便等特点。  相似文献   
135.
ABSTRACT: Effectively teaching water resources policy to university science and engineering students is both important and difficult. Most careers in the water resources field require an understanding of the comprehensive governmental regulatory structure affecting water use. Also, few science and engineering curricula encourage their students to take policy courses. Successful approaches to teaching water resources policy might include epistemological comparisons, case studies, issue maps, and interactive simulations. Obstacles to the effective teaching of this subject include students' insufficient preparation and student disdain and cynicism. These obstacles may be mitigated by requiring a prerequisite, developing a glossary of policy-related terms, and introducing the course through lectures emphasizing realistic views of the water resources management field and the nature of the American political system.  相似文献   
136.
本文根据层次分析法的原理,结合环境工程评标的特点,建立了评定最优环境工程方案的层次结构模型。该模型引入三标度法来间接地构造判断矩阵,简化了专家或决策者的判断难度,增强了判断矩阵的逻辑性。结合某废水治理工程项目,介绍了层次分析法应用于工程评标的计算过程。结果表明,这种改进的层次分析法是进行环境工程方案优选的新颖、科学、简便的方法。  相似文献   
137.
ABSTRACT: A research project was undertaken for the U.S. Army Corps of Engineers to determine the relative utility and effectiveness of four well-known multicriteria decision making (MCDM) models for applications in realistic water resources planning settings. A series of experiments was devised to examine the impact of rating and ranking procedures on the decision making behavior of users (e.g., planners, managers, analysts, etc.) when faced with situations involving multiple evaluation criteria and numerous alternative planning projects. The four MCDM models tested were MATS-PC, EXPERT CHOICE, ARIADNE, and ELECTRE. Two groups of analysts and decision makers were tested. One group consisted of experienced U.S. Army Corps planners, while the other was comprised of graduate students. Based on a series of nonparametric statistical tests, the results identified EXPERT CHOICE as the preferred MCDM model by both groups based largely on ease of use and understandability. ARIADNE fostered the largest degree of agreement within and among the two groups of individuals tested. The tests also lend support to the claim that rankings are not affected significantly by the choice of decision maker (i.e., who uses any of these MCDM models) or which of these four models is used.  相似文献   
138.
ABSTRACT: Game-theoretic models are developed for describing and analyzing the inspection and enforcement process, especially as it relates to environmental laws and regulations in North America. Based on these models, systems using irrevocable control orders can be compared to those relying on court determination of guilt and punishment. The cost-effectiveness of environmental enforcement can be systematically assessed in terms of factors such as the private gains for violators, the costs of inspection, penalties, and the social value of deterring violations. The policy implications of the analysis, especially with reference to environmental protection, are emphasized.  相似文献   
139.
The current Mexican environmental law provides the legal basis for comprehensive land-use planning. Under the law, development of natural ecosystems must combine goals, policies, and practices towards the sustainable use of natural resources and the protection of biological diversity. Thus, ecosystem manipulation must be able to counter fragmentation of natural ecosystems and isolation of natural reserves, while providing for human needs. Assessment of the potential of natural ecosystems and management impacts are required. Multiple-resource simulation is an assessment and land-use planning tool that permits managers and decision makers to comply with the law, providing a flexible, user-oriented system that can meet the needs of managers, conservationists, and researchers. A multiple-resource model and an example of how it can be applied to meet planning needs is presented for discussion.  相似文献   
140.
自行研制了新型聚合铝铁絮凝剂,并将其用于造纸废水的处理.絮凝剂的组分和用量对造纸废水的处理有明显影响.实验结果表明,该絮凝剂在用量为1.5~3.0ml的范围内,可以去除60%以上的CoD,废水中悬浮物的去除率高于75%,色度去除率可以达到69%以上.  相似文献   
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