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991.
汕头市降雨量的概率分布模型   总被引:1,自引:0,他引:1  
任晓崧 《灾害学》1999,14(1):11-16
根据汕头市实测的年最大日降雨量资料,采用极值Ⅰ型、极值Ⅱ型、极值Ⅲ型和Weibull分布等四种极值分布模型模拟,从而确定了年的最大日降雨量的概率模型.并根据年的各时段的最大降雨量仪器记录产生概率模型,建立各时段降雨量之间的相互关系,得到汕头市降雨量的概率分布模型,作为汕头市内涝分析的依据。  相似文献   
992.
ABSTRACT. The Heat Storage Well concept evolved at TEMPO in 1972. Technical, economic, institutional, and legal aspects of implementing the concept are being studied. Heat Storage Wells offer the possibility of conserving a substantial part of the heat energy now wasted in generating electricity and of reducing thermal pollution caused by the waste heat. Large thermal electric power plants would produce heat at useful temperatures such as 300–400°F. Combined electric- and heat-generating systems will require low-cost, low-loss storage of large amounts of hot water for periods of 90 to 180 days to serve both electric loads and seasonally-varying heat loads. Compared to conventional electricity-only systems, combined electricity-heat systems can save more than 20 percent in energy, reduce the cost of both electricity and heat, and eliminate the need for cooling water or towers. Possibilities for changes in legal and institutional practices are suggested, such as making resource-allocation decisions on the basis of energy units rather than dollars.  相似文献   
993.
ABSTRACT A mathematical programming model is structured to find the optimal time and capacity expansion path of desalination plants and storage tanks for a hypothetical community which depends on desalination as its sole, or major, water supply source. The objective is to determine the least costly combination of sues and times of installation (of both desalting plants and storage tanks) which can meet a rising water demand over a finite planning horizon. The optimality criterion used in the model is based on two major economic elements: the economies of scale inherent in such facilities and the time-value of money represented by the interest rate, the former favoring large capacities and the latter small capacities. The model is applied using three population growth patterns and two interest rates. The water demand components for every year in the planning period are computed using empirical formulas which are based on population and other basic data. The model is solved for each of the above cases with the aid of a computer program based on the method of feasible conjugate directions. The results clearly reflect the balance between the economies of scale and the time-value of money under every demand growth function.  相似文献   
994.
ABSTRACT Relevant information on the restoration of lakes is presented. The restoration procedures considered are applicable to the water, the bottom sediments, and aquatic plant improvement. A summary of thirteen (13) suggested methods of restoration are reviewed.  相似文献   
995.
Technology assessment (TA) as aninstitution was introduced nearly thirty yearsago as an instrument to render possible themaking of responsible decisions concerning newtechnological options. Another recentdevelopment however has been the introductionof participatory technology assessment (pTA),mainly connected to the growing insight thatthe evaluation of technological options withrespect to their risks and benefits, is not –only – a scientific question. This paper willfocus on the questions, to what degree theideas of technology assessment and thePrecautionary Principle are connected and how.Without naming it explicitly, the PrecautionaryPrinciple is put to debate in the``TA-arrangement on the cultivation oftransgenic herbicide resistant crops,'organized by the Science Centre, Berlin. Fromthe perspective of ethical clarification, someunique features concerning theconceptualization of the discoursive procedureand reconstruction of the argumentation processin order to come to results have to beanalyzed. Finally the performance and resultsof the pTA-arrangement are reflected in thelight of the Precautionary Principle andconclusions are drawn.  相似文献   
996.
以人为本的现代工业安全管理   总被引:1,自引:2,他引:1  
现代生产中发生的意外事故 ,80 %以上是由于人的因素造成的。笔者运用人机工程学和行为科学理论 ,对人的不安全行为和因素进行了深入的归类分析 ;阐述了人因事故预测和预防对策 ;指出工业安全管理应该从人的角度出发 ,系统地建立安全管理体系 ;最后 ,运用系统工程的观点 ,提出了构建以人为本的安全管理体系的结构 ,该体系的实行将能够使现代工业安全管理提高到一个新的水平。  相似文献   
997.
吉林省历史文化遗存类科普旅游资源的开发   总被引:1,自引:0,他引:1  
科普旅游是以游览为目的,在游览过程中普及科学知识,集娱乐性、参与性、知识性、教育性于一体的旅游活动.从吉林省的历史文化遗存出发,分重点城市和专项两个方面探讨了吉林省历史文化遗存的科普旅游开发.  相似文献   
998.
以乌鲁木齐市供采暖系统为背景,用清洁生产的思维方式发现和解决采暖过程中热能的浪费。通过对可发性聚苯乙烯泡沫塑料板的保温性能和目前民用墙体保温技术发展状况、发展方向及其经济、环境效益的分析,提出大力推广外墙保温技术、实现建筑节能是必然的发展趋势;同时实行分户供暖、计量收费更是推行节能建筑的重要保障。  相似文献   
999.
Private and public interests in water and energy   总被引:1,自引:0,他引:1  
Based on empirical evidence from developed, transition and developing countries, the article looks at how the introduction of private operators’ interests into the water supply/sanitation and energy sectors may conflict with public interests in socio‐economic, environmental and political dimensions. Case studies are used to illustrate the dynamics of these interactions, covering phenomena such as unsolicited proposals, misrepresentation and corruption; the exploitation of established positions by taking advantage of asymmetry of information and negotiating capacity in relation to public authorities; and exit from contracts or concessions when acceptable profitability cannot be attained. This experience indicates that the introduction of private companies into these sectors creates the permanent possibility of conflict between private and public interests. The services are too vital both socially and economically to rely on corporate self‐regulation, and countries lack effective capacity to regulate such corporations. The authors conclude that policies relying on corporate activity in these sectors are unnecessarily risky, and that policy development should focus on building strong public sector institutions to provide these services.  相似文献   
1000.
Different bioassays with higher plants were approved for use in a bioassay procedure for testing of xenobiotics according to the German Chemicals Act. Selected environmental pollutants (atrazine, cadmium chloride, 2,6-dichlorobenzonitrile, pentachlorophenol, potassium dichromate, thiourea), all from a list of reference chemicals, were tested with these methods. Dose-response curves for growth of oats and turnips were evaluated in soil and vermiculite (nonsorptive substrate), and availability to plants was calculated by comparing the EC50 values for one chemical in both substrates. The most active chemical was atrazine, followed by 2,6-dichlorobenzonitrile, pentachlorophenol, potassium dichromate, cadmium chloride, and thiourea. The least available compound to plants was pentachlorophenol, tested with turnips (Brassica rapa var.rapa). The strongest inhibition of germination, demonstrated in an in vitro assay with garden cress (Lepidium sativum), was found with 2,6-dichlorobenzonitrile, the lowest with atrazine. The effect of an extended exposure of the plants to the chemicals was evaluated in a long-term bioassay with oats (Avena sativa) in hydroponic culture. Several dose-response curves during the growing period were derived. It was found that the EC50 values for atrazine and thiourea decreased markedly during the first four weeks; thereafter the changes were much smaller. As an overall conclusion, a bioassay procedure is proposed that can be included in the graduated plan recommended by the German Chemicals Act.  相似文献   
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