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81.
准确评估鱼雷武器系统作战效能是最大限度发挥潜艇作战系统效能的必要前提.运用层次分析法和模糊数学理论对鱼雷武器系统效能进行了定性分析和定量计算,对如何公正、客观、合理地评估鱼雷武器系统作战效能做出了有益的探索.  相似文献   
82.
地理信息系统(GIS)技术现已广泛应用于环境领域。简要介绍了该技术的功能特点,并从大气、水、土壤、噪声四个方面探讨了GIS在环境保护中的应用。研究结果表明,GIS是研究环境子系统协同效应的实用技术。  相似文献   
83.
84.
Hay RW 《Disasters》1986,10(4):273-287
This paper begins by setting out the main arguments on which a proposal for "relief-development strategies" rest. The second part of the paper is concerned with a discussion of the way the objectives of a "relief-development strategy" might be achieved and the roles emergency food aid might have. In the third part of the paper, a number of strategic issues are discussed. A stylized account is presented of how a broad "relief development strategy" might be mounted. The last part of the paper draws together the discussion by considering how emergency projects should be assessed. If the principles on which this paper are based are accepted, then the evaluation of emergency projects should extend well beyond convention.  相似文献   
85.
王晓楠 《中国环境科学》2020,40(8):3495-3505
运用计划行为理论和A-B-C理论,结合强政策背景下上海垃圾分类的实际,完善居民生活垃圾分类行为测量量表,改进并区分居民垃圾分类目标意愿和执行意愿,构建城市居民垃圾分类行为影响路径理论模型.基于“2019年上海居民垃圾分类行为”调查数据,覆盖上海16个区县的2555有效样本,运用结构方程模型验证强政策背景下居民环境态度、主观规范和感知行为控制对垃圾分类行为影响路径.结果表明:环境态度、主观规范、感知行为控制分别对居民垃圾分类目标意愿和执行意愿有显著正向的影响.环境态度分别通过目标意愿和执行意愿对垃圾分类行为产生间接效应.主观规范和感知行为控制并没有通过两类意愿对垃圾分类行为产生间接效应.垃圾分类的政策效能感在目标意愿对垃圾分类行为效应中起到了调节作用.虽然环境态度、主观规范、感知行为控制可以促进公众垃圾分类行为目标意愿和执行意愿的形成,但仅有环境态度可以通过激发公众目标意愿和执行意愿进而形塑居民垃圾分类行为.  相似文献   
86.
目的落实油气管道定期检验工作,确保管道安全平稳运行,方法通过对西南管道公司所辖某天然气管道进行外腐蚀直接检测,包括管线敷设环境调查、防腐层状况不开挖检测、管道阴极保护有效性评价检测以及开挖直接检验。根据检测结果进行合于使用评价,包括应力分析计算、剩余强度评估、管道剩余寿命预测等。结果管道允许使用,再评价间隔5年。结论直接检测方法采用多种检测手段对管道外腐蚀情况和防腐保护系统进行管道全面检验,并出具合于使用评价,是一种综合的完整性评价方法,符合法定检验的要求,其评价结果可作为管道完整性管理的可靠依据,可据此制定管道的维修方案和预防措施。  相似文献   
87.
Abstract: The current shortfall in effectiveness within conservation biology is illustrated by increasing interest in “evidence‐based conservation,” whose proponents have identified the need to benchmark conservation initiatives against actions that lead to proven positive effects. The effectiveness of conservation policies, approaches, and evaluation is under increasing scrutiny, and in these areas models of excellence used in business could prove valuable. Typically, conservation programs require years of effort and involve rigorous long‐term implementation processes. Successful balance of long‐term efforts alongside the achievement of short‐term goals is often compromised by management or budgetary constraints, a situation also common in commercial businesses. “Business excellence” is an approach many companies have used over the past 20 years to ensure continued success. Various business excellence evaluations have been promoted that include concepts that could be adapted and applied in conservation programs. We describe a conservation excellence model that shows how scientific processes and results can be aligned with financial and organizational measures of success. We applied the model to two well‐documented species conservation programs. In the first, the Po’ouli program, several aspects of improvement were identified, such as more authority for decision making in the field and better integration of habitat management and population recovery processes. The second example, the black‐footed ferret program, could have benefited from leadership effort to reduce bureaucracy and to encourage use of best‐practice species recovery approaches. The conservation excellence model enables greater clarity in goal setting, more‐effective identification of job roles within programs, better links between technical approaches and measures of biological success, and more‐effective use of resources. The model could improve evaluation of a conservation program's effectiveness and may be used to compare different programs, for example during reviews of project performance by sponsoring organizations.  相似文献   
88.
Freshwater protected areas are rare even though freshwater ecosystems are among the most imperiled in the world. Conservation actions within terrestrial protected areas (TPAs) such as development or resource extraction regulations may spill over to benefit freshwater ecosystems within their boundaries. Using data from 175 lakes across Ontario, Canada, we compared common indicators of fish‐assemblage status (i.e., species richness, Shannon diversity index, catch per unit effort, and normalized‐length size spectrum slopes) to evaluate whether TPAs benefit lake fish assemblages. Nearest neighbor cluster analysis was used to generate pairs of lakes: inside versus outside, inside versus bordering, and bordering versus outside TPAs based on lake characteristics. The diversity and abundance indicators did not differ significantly across comparisons, but normalized‐length size spectrum slopes (NLSS) were significantly steeper in lakes outside parks. The latter indicated assemblage differences (greater abundances of small‐bodied species) and less‐efficient energy transfer through the trophic levels of assemblages outside parks. Although not significantly different, pollution‐ and turbidity‐tolerant species were more abundant outside parks, whereas 3 of the 4 pollution‐intolerant species were more abundant within parks. Twenty‐one percent of the difference in slopes was related to higher total dissolved solids concentrations and angling pressure. Our results support the hypothesis that TPAs benefit lake fish assemblages and suggest that NLSS slopes are informative indicators for aquatic protected area evaluations because they represent compositional and functional aspects of communities.  相似文献   
89.
按照应力、疲劳、锈蚀、腐蚀等失效原理,结合由于雷击所造成的具体事故案例,对避雷针(网)进行失效分析。同时,从“人机环”本质安全化的角度,提出了预防、预控、预测的对策。  相似文献   
90.
Abstract: Recent literature on systematic conservation planning has focused strongly on economics. It is a necessary component of efficient conservation planning because the question is about effective resource allocation. Nevertheless, there is an increasing tendency toward economic factors overriding biological considerations. Focusing too narrowly on economic cost may lead us back toward solutions resembling those obtained by opportunistic choice of areas, the avoidance of which was the motivation for development of systematic approaches. Moreover, there are many overlooked difficulties in incorporating economic considerations reliably into conservation planning because available economic data and the free market are complex. For instance, economies based on free markets tend to be shortsighted, whereas biodiversity conservation aims far into the future. Although economic data are necessary, they should not be relied on too heavily or considered separately from other sociopolitical factors. We suggest focusing on development of more‐comprehensive ecological‐economic modeling, while not forgetting the importance of purely biological analyses that are needed as a point of reference for evaluating conservation outcomes.  相似文献   
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