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901.
徐佳昕  游波  刘永胜  施式亮  褚涛 《安全》2019,40(2):19-23
为了找出铸造厂电炉设备存在的危害因素,本文通过分析辨识湖州某铸造厂电炉存在的危险源,采用层次分析法对该厂电炉这一重大危险源进行安全评价,结果表明,人员管理因素中作业人员的安全态度对电炉事故影响最大。根据评价结果,从安全管理方面提出电炉事故预防的对策措施。  相似文献   
902.
阮小明 《灾害学》1993,8(4):37-40
本文在分析湖北省局部地区自然疫源变化及疾病趋势的基础上,指出了南水北调中线工程可能对地氟病、血吸虫、疟疫、乙脑及其它水源性疾病所带来的影响,并提出了建设性的建议和对策。  相似文献   
903.
Environmental research is characterized in each of its successive phases by a strong interdisciplinarity. A rotational groups system (RGS) method is proposed as an instrument to encourage interaction among researchers from fields that are traditionally far apart. Meetings conducted with the RGS procedure involve all the researchers, who, in repeated and topical encounters, are able to exchange information on a wide variety of environmental subjects. These meetings can be arranged according to a special calendar, through a series of phases treating different aspects of the same subjects to be discussed, and above all, referring to specific themes and working guidelines organized on the basis of criteria designed to favor an exchange of ideas and constructive discussion. At the end, the plenary assembly edits an overall resume of the proceedings, and votes on the final resolution, which brings together all the conclusive opinions regarding the themes discussed.  相似文献   
904.
ABSTRACT: The deliberate underwatering of a larger land area, as practiced in Southern Asia, has provided impetus for a systematic investigation into the effects of designing projects for crop water deficits on Benefit-Cost performance. The study began with the derivation, from published experimental results, of functions relating ultimate crop yield to the magnitude and timing of water deficits, i.e., of the productivity of irrigation water. To obtain the net benefit of the project, the relation between the harvested area and output and the on-farm production costs was then suggested. The cost of supplying the irrigation water to the proposed area and of distributing and applying it to the field was determined, thus completing the Benefit-Cost equation. A computer simulation model was then established to search for the irrigation project design capacity and area to maximize the net present value in the Benefit-Cost analysis for the development proposed.  相似文献   
905.
分析了我国高等学校开设安全工程专业的发展状况,提出安全工程专业应以安全科学技术知识为主体,兼顾生产知识,设置专业基础课程和专业课程,形成安全工程的专业特性。  相似文献   
906.
ABSTRACT: Southeast Asian nations with extensive water management systems have numerous candidate and ongoing programs and projects. They cannot possibly all be funded and implemented simultaneously in any serious way. Choices must be made. But how to select? What criteria can assist with the screening in an acceptable manner, particularly in the near absence of useful technical and economic information across them all. This paper suggests a methodology by which assessment criteria can be constructed which conforms to any given national information base and development needs. Criteria can be weighted one against the other in their relative importance. For each criterion a ranking scale puts the “best” (most, highest) at one end and the “worst” (least, lowest) at the other. Each candidate project is then subjected to these consistent assessment methods for a weighted “score.” Key criteria normally have surrogate measures depending on information available. Criteria are of three sorts: sheer volume, e.g., of a specific use, a benefit; ratios and relations, e.g., A as percent of B; and other more subjective criteria, e.g., regional or income distribution impacts. The basic criteria include, for example, time to full benefits (minimize), OM & R as percent of investment (minimize), and permanent rural jobs created (maximize).  相似文献   
907.
西湖引水治理后的底栖动物群落   总被引:3,自引:0,他引:3  
1995年1月-1996年12月对西湖底栖大型无脊椎动物群落进行了连续监测与研究,共发现大型底栖无脊椎动物26种,其中寡毛类6种,多毛类1种,水生昆虫9种,蛭类,线虫和无节蠕虫各1种。  相似文献   
908.
密切值法在污水土地处理工程选址中的应用   总被引:4,自引:0,他引:4  
本文对密切值法在污水土地处理工程选址中的应用进行了探讨,通过实例分分析看出该方法科学可行且简易。  相似文献   
909.
Species characterized by female-defense polygyny have extreme variance in male mating success. Many studies have considered alternative male strategies for access to females, but few have considered age-specific strategies. Male boat-tailed grackles (Quiscalus major) compete for access to colonies of females and form linear dominance hierarchies. I observed two groups of males that competed for females at seven colonies. Dominance rank was significantly correlated with mass, but not after controlling for age. In contrast, the correlation between dominance rank and age remained significant after controlling for mass. Older males dominated younger males and dominance relationships were very stable. Thus, dominance hierarchies represent queues for mating opportunities. A male's rank in the hierarchy determined how closely he approached a colony. Furthermore, males of all ranks prevented lower-ranked individuals from approaching the colonies. Dominance rank thus determined access to nesting females. One top-ranking male's loss of mass over the course of the breeding season presumably reflected the energetic cost of defending females, but he maintained his position in the hierarchy despite the small loss of mass. One alpha male held a colony for at least 4 years, and the ages of males from two queues indicated that males wait 6 or more years before becoming an alpha male. Therefore, most males die before acquiring a colony of females. Spatial structure such as that documented here could obscure recognition of queues and explain why they have not been documented in more species. Received: 13 May 1996 / Accepted after revision: 26 April 1997  相似文献   
910.
玄武湖引水工程的环境效益分析   总被引:6,自引:0,他引:6  
从现有引水工程环境实施效果入手,通过小试试验,响应模型计算及投资效益分析,提出了引水工程的改进方案。  相似文献   
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