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441.
This paper discusses a procedure for case studies of accidental gas explosions. The procedure for each case study can be subdivided into four steps, i.e., collection of proofs, analyses, confirmation, and inference about the processes of the accident, and the issues in each step are pointed out. Making a guess on the sequence of the accident to be investigated should be avoided during collection of proofs. Misunderstanding of the phenomena in analyses and confirmation is likely caused by inappropriate knowledge on the phenomena and/or use of unsuitable models. The sequence of the accidental gas explosion should be inferred on the basis of confirmed processes. If there are other possibilities, those should be described in the report. The reasonableness of the results of a case study depends on the rationality of the procedure and the quality or plausibility of knowledge to infer the probable sequence. 相似文献
442.
Robert C. Waters 《Journal of the American Water Resources Association》1980,16(2):256-260
ABSTRACT: Federal spending on water resource development projects exceeds $10 billion annually. This paper examines the economic theory and practice on which the Federal water resource development plans are based. Existing theoretical and applied problems result in overinvestment. These include 1) no standard of value for the tradeoff of environmental objectives with economic objectives; 2) benefits based on “willingness to pay,” but beneficiaries pay only a fraction of a project's costs; 3) beneficiaries “shop around” among program purposes in order to reduce their commitments; and 4) benefit/cost (B/C) analyses are based on a discount rate, which is consistently below the Federal borrowing rate. Furthermore, the Government Accounting Office (GAO) frequently finds that the agency regulations are inadequate and result in inconsistent and questionable benefit computations. The President has proposed a series of water policy reforms, to reduce some of the apparent overinvestment in water resource development, but fundmental corrective action rests with the members of Congress. 相似文献
443.
Jay R. Stauffer Kenneth L. Dickson John Cairns 《Journal of the American Water Resources Association》1974,10(5):860-876
ABSTRACT. Studies were conducted to determine the distribution of fish in the New and East Rivers in relation to thermal discharges from Appalachian Power Company's fossil fuel plant at Glen Lyn, Virginia. Over 15,300 specimens representing 41 species were collected with seines, electrogear and rotenone at six sampling locations from February, 1973 to October 1973. Sampling frequency was designed to evaluate the effects of ambient temperature upon preferred temperature. Diversity indices were calculated for each location. There was a slight decrease in the diversity indices for those stations located in the thermal discharge. Condition coefficients calculated for Notropis albeolus Jordan, Notropis rubellus Aqasaiz, Notropis spilopterus Cope, Ictalurus punctatus Rafinesque, and Etheostoma blennioides Rafuesque were found to be significantly (p =.05) lower in the thermal discharge for all species tested except E. blennioides. Temperatures were plotted against frequency of capture to determine a particular species temperature selection from field data and indicated that: (1) Some species avoided high temperatures (i.e., Curnpostoma anomalum Rafuesque). (2) Some species were attracted to high temperatures (i.e., Ictalurus punctatus). (3) Some species distribution was not effected by temperatures (i.e., Notropis spilopterus). 相似文献
444.
王睿 《中国环境管理干部学院学报》2005,15(4):36-37
基层环境行政执法存在较为严重的有法不依、执法不严、违法不纠、以权代法等现象.通过突出环境执法宣传、提高执法能力、加强强制执行权和部门协调等方面,提出了新形势下强化基层环保执法工作的对策. 相似文献
445.
郭黄金 《中国环境管理干部学院学报》2005,15(4):110-111,114
通过对高职院校学生的学风现状分析,指出了其成因,提出了适合高职院校加强学生的学风建设的方法和途径. 相似文献
446.
黄丽 《中国环境管理干部学院学报》2005,15(4):112-114
"研究性学习"教学模式,促使教学理念发生根本的改变,它以学生的发展为根本,注重教学活动中学生素质的形成过程,使学生在主动、互动的学习过程中有所思、有所为、有所得,使学生的学习水平、科学意识、人文思想、实践能力、创新精神等得到全面发展. 相似文献
447.
我国石油消费现状及其战略思考 总被引:1,自引:0,他引:1
石油是支撑经济发展和国防现代化的基本能源之一。在当今国际社会中 ,石油已成为世界政治、经济、军事和外交斗争的特殊武器 ,成为一国经济发展、社会稳定以及国家安全的重要保障条件。我国目前石油供需形势严峻 ,主要表现为 :石油储量接替准备不足 ,老油田稳产面临严峻形势 ;需求增长过快 ;对外依存度较高 ;运输和贮存能力较小等方面。石油的安全及其保障问题关系到我国的经济安全和国家安全 ,因此 ,有必要研究我国的石油消费现状及发展战略。笔者针对我国的石油消费现状 ,分析了目前我国石油战略中存在的问题 ,探讨了我国的石油战略。 相似文献
448.
近年来 ,我国国民经济快速发展 ,但安全生产状况不容乐观 ,安全事故频繁发生 ,事故死亡人数居高不下。笔者在对 1993~ 2 0 0 0年我国安全生产数据进行分析的基础上 ,应用最小二乘法拟合技术研究安全生产与安全事故的内在联系 ;建立人均GDP、人均安全投入、人均安措投入、人均劳保投入与 10万人死亡率和亿元GDP死亡率的函数关系 ;探讨造成安全生产事故的原因 ;进一步完善了安全理论。上述对安全生产中若干问题研究的思路和方法 ,为安全生产的宏观决策和预防事故的发生提供了重要理论和科学依据。 相似文献
449.
Main R. Hutcheson 《Journal of the American Water Resources Association》1998,34(5):1025-1033
ABSTRACT: Acute criteria are assigned to the fish and wildlife propagation beneficial use in Oklahoma's water quality standards. Dye studies are analyzed to show that these criteria can be implemented through acute regulatory mixing zones. Acute regulatory mixing zones may be defined as areas in receiving streams where acute numerical criteria may be exceeded without causing acute toxicity. Acute regulatory mixing zones are used to obtain acute waste load allocations. If effluent loading does not exceed acute waste load allocation, acute criteria exceedance is confined to the acute regulatory mixing zone and there is no acute toxicity in the receiving stream. Waste load allocations for acute and chronic criteria are compared to determine which is appropriate to develop permit limits for the dye studies. 相似文献
450.
采空区火源位置探测技术现状及发展方向 总被引:3,自引:0,他引:3
概述了国内外采空区火源位置探测技术的现状,着重介绍了温度探测法、气体探测法、磁力探测法、数理解算法、电磁波探测法及电阻探测法等探测技术,并展望了国内外采空区火源位置探测技术的发展方向 相似文献