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排序方式: 共有782条查询结果,搜索用时 15 毫秒
81.
浅谈我国冰雹的分布规律及其保险对策   总被引:2,自引:0,他引:2  
李加明 《灾害学》1992,7(1):34-38
本文从冰雹灾害的分布规律着手,研究我国雹灾对策形式之一——雹灾保险,在对世界各国雹灾保险借鉴的基础上,选择我国雹灾保险的模式,建立适合我国国情的雹灾保险。  相似文献   
82.
83.
根据我国宪法和地方组织法等的规定,对地方环境立法中的若干关系问题,从理论和实践的结合上作了探讨。  相似文献   
84.
ABSTRACT: This paper presents the implementation of one element of a decision support system (DSS) for regional water quality management, applied to the Nitra River Basin in Slovakia. A model-based, aspiration-led methodology for multicriteria decision support has been used for the study. Several reusable, modular software tools have been developed and implemented: a problem-specific generator to produce the core part of the mathematical programming model, tools for the generation and interactive modification of multicriteria problems, and a solver for the resulting mixed-integer optimization problem. Provided in the paper are the following: a complete formulation of the mathematical model (including the imbedded water quality model), a summary of the aspiration-reservation-led multiple criteria optimization approach applied to decision support, and an overview of results that illustrate the applied approach and provide some interesting insights to the case study.  相似文献   
85.

Background, Aim and Scope

The paper investigates the development of the institutional basis of the present modes of chemicals regulation and management, with special attention to interrelations with the precautionary principle. Main Features: The paper elucidates on how the precautionary principle has been shaped in relation to chemicals regulation and management since Carson's Silent Spring (years before the principle was confirmed as a policy-principle in German and European legislation. Furthermore, it is examined how the precautionary principle interacted with the development of the present chemicals regulatory regime, in a complex interplay within the OECD and Member Countries. The present modes of precaution in the new EU chemical legislation – REACH – are investigated with respect to the precautionary principle, and tested against two contemporary problems; brominated flame retardants and endocrine disrupting substances. Results: The analysis demonstrates the changing character of the integration of the precautionary principle. The main tendencies are from implicit to more explicit precaution and from a closed expert-orientation towards a more deliberative approach to scientific knowledge and uncertainty. The results demonstrate that the precautionary principle is manifest in both the design of the testing strategy and in policy provisions. In particular, the substitution of hazardous substances with less hazardous is important. Discussion: Despite explicit attention to the precautionary principle, is the present reformulation of the European Chemicals policy in danger of falling into loop-holes that equal problems related to the present regulation of existing chemicals? 'Precaution' has been reduced virtually to an abstract concept that is more or less devoid of practical meaning in the regulatory process. Conclusions: It is concluded that the role of the precautionary principle in chemicals regulation will require continued scrutiny in the future shaping of the REACH strategy. Perspectives: Continued development of robust and precaution-based chemicals regulation will have to involve both new data-generation strategies and new forms of political decision-making, with special attention given to transparency and deliberative policymaking.  相似文献   
86.
We investigate the stock market response to firm disclosure of positive environmental information and the link from that information to environmental outcomes. We classify environmental media releases by informational content and value relevance, and assess the abnormal stock returns of each type of event. While announcements of future environmental activities lead to the largest favorable stock market reactions, there is no guaranteed link from this type of information to environmental outcomes. Further analysis of the abnormal returns shows that the magnitude of the stock market reaction depends on firm financial characteristics across all event types rather than on firm environmental performance. Our results indicate that the ability for voluntary environmental information disclosure to induce environmental self-regulation is limited to the extent that firms are able to follow through with their announcements of planned environmental activities.  相似文献   
87.
我国土壤污染风险规制在专家遴选标准、建设用地和农用地污染风险管控要求,以及风险管控措施等方面存在不同程度的行政裁量。社会理性和科学理性的缺失形成了土壤污染风险行政裁量困局。土壤污染信息制度中“适时公开”的规定使得公众缺乏必要污染信息,弱化其参与程度,导致对行政决定合法性的质疑。此外,土壤污染风险管控标准中专家遴选标准和论证规则的欠缺导致土壤污染风险规制科学理性的缺失。为此,需要建构关照事实和规范的协商式行政裁量模式,强调公众的实质性参与以弥合技术理性和公众理性的鸿沟。同时,在程序上确定专家遴选标准和风险管控标准的论证规则以保证土壤污染风险管控的科学性和客观性。在不妨碍行政裁量权灵活性和能动性的前提下,规范行政裁量权的行使,控制行政裁量权的滥用。  相似文献   
88.
为评价矿井热环境中工人职业健康安全状况,提出矿井热宽温度环境人体热健康状态的基本特征与生理要求,分析热宽温度环境人体分区热调节规律与热健康状态的对应关系。基于生物控制论的观点,提出热宽温度范围内不同热应力作用下人体分区热调节机制,建立人体分区热调节模型。结果表明:模型能实现对环境热应力作用下人体物理热平衡状态与生理状态的参数化描述,揭示多因素作用下人体热健康状态的热应力边界与变化规律。分区热调节模型提供了人体热健康状态定量模拟平台,通过参数调整可使模型适应研究需求,模型为井下热环境工人职业健康安全状况分析与评价提供了可参考的思路与方法。  相似文献   
89.
This paper focusses on a conceptual overview of ways to address a comprehensive analysis of ecosystem services (ES) in a country as large and heterogeneous as Russia. As a first step, a methodology for assessing the services for the federal subjects of Russia was chosen, i.e., its constituent provinces and similar entities, in physical terms. Russia harbors a great diversity of natural conditions and ecosystems which are suppliers of ES, and likewise a variety of the socio-economic conditions that shape the demand for these services and their consumption. The methodological approach described permits several important tasks to be addressed: the evaluation of the degree of satisfaction of people’s needs for ES, the identification of ecological donor and acceptor regions, and zoning of the country’s territory for ES assessment. The next step is to prepare a prototype of a National Report on ES in Russia, for which we are presenting the planned structure.  相似文献   
90.
Over the last three decades, ambient concentrations of sulfur dioxide (SO2) air pollution have declined by approximately 80%. This paper tests whether the 1970 Clean Air Act and its subsequent amendments caused this decline. The centerpiece of this legislation is the annual assignment of all counties to SO2 nonattainment or attainment categories. Polluters face stricter regulations in nonattainment counties. There are two primary findings. First, regulators pay little attention to the statutory selection rule in their assignment of the SO2 nonattainment designations. Second, SO2 nonattainment status is associated with modest reductions in SO2 air pollution, but a null hypothesis of zero effect generally cannot be rejected. This finding holds whether the estimated effect is obtained with linear adjustment or propensity score matching. Overall, the evidence suggests that the nonattainment designation played a minor role in the dramatic reduction of SO2 concentrations over the last 30 years.  相似文献   
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