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81.
区域地震间接经济损失评估   总被引:1,自引:0,他引:1  
对区域地震间接经济损失的研究现状进行了总结和回顾,目前主要有基于国内生产总值、基于地震震级和基于地震直接损失的3种评估计方法,对这些评估方法进行了讨论,结合地震现场的工作性质和特点,给出了现场评估的一般步骤和建议。  相似文献   
82.
由于灾害损失本身的复杂性及灾情统计方面存在的问题,利用区间数替代单一实数值作为灾害等级评估指标的输入更加符合实际。基于上述思路,提出了一种基于区间数的灾害等级评估新模型。首先,给出区间数距离的新定义,该定义能够充分利用区间数所携带的信息;然后,利用线性加权评价函数计算评估对象与评价标准之间的综合相对距离测度,评估对象隶属于综合距离测度最小值所对应的灾害等级。该模型建模过程思路清晰,物理意义明确,计算过程简捷,评估结论符合实际。最后,用实例说明模型的应用方法。  相似文献   
83.
根据中国道路交通事故经济损失的研究现状,借鉴国外对道路交通事故经济损失研究的成功经验,提出适用于中国实际情况的交通事故社会公共机构服务损失费用构成;确定了道路交通事故社会公共机构服务损失评价指标体系。基于经济学和统计学理论,主要从警方服务、清障服务、管理部门服务和法律诉讼服务4个方面对道路交通事故社会服务损失进行了深层次理论分析与评价;构建了相应的评价计量模型;提出了我国评价交通事故社会服务损失的一些合理化建议。研究结果对科学、全面、合理地评价道路交通事故社会经济损失具有重要的实际意义。  相似文献   
84.
为了解听力防护用品使用过程中的问题,提高我国噪声暴露工人听力防护用品的使用率和有效率,选择噪声危害较大的某飞机维修公司的员工,进行听力防护用品使用情况的问卷调查。结果显示:该公司为员工提供耳塞和耳罩两种听力防护用品;员工的听力保护意识、使用情况较好,使用率达95%,但对听力防护用品相关知识的了解不够全面;能够在工作中一直坚持使用的工人较少,仅占11%,影响工人工作时间使用听力防护用品时间长短的因素主要是其舒适性。调查分析提示:在未来听力防护用品的生产过程中,需要进一步加强和改善舒适性的技术;政府、企业和个人3方面共同参与,降低职业性噪声暴露对工人听力的损伤。  相似文献   
85.
ABSTRACT: The continuous availability of ground water to riparian phreatophytic vegetation results in large evapotranspiration (ET) losses in summer. Chemical or physical eradication of this vegetation can have undesirable environmental side effects. Spraying phreatophyte foliage with a nontoxic antitranspirant (AT) may reduce transpiration without eradication. Transpiration rate per unit leaf area was similar for several phreatophyte species, but ET per unit land area of phreatophytes depneds more on stand density than species. The mean ET for saltcedar in June was 8.1 mm/day measured by Bowen ratio, compared with 7.9 mm by lysimeters. ATs and growth-retardants reduced transpiration by over 50 percent in laboratory tests where foliage was thoroughly sprayed. In the field AT sprayed by a back-pack mistblower reduced ET by 20–35 percent initially and 10 percent after a month. No ET reduction occurred when AT was sprayed by helicopter on saltcedar, because excessive droplet size and heavy salt deposits on the foliage resulted in poor spray adherence. Wax-based AT was relatively nontoxic to fish and wildlife. Dissolved oxygen could be reduced for aquatic life, but further AT dilution in streams and ponds would minimize this. Helicopter spraying may affect bird nests and egg hatchability. Although ATs significantly reduce ET, their high cost and spraying difficulties preclude current use on phreatophytes. With improvement they may economically help to conserve water in riparian areas in future years.  相似文献   
86.
Two intermittent streams on oak-hickory watersheds in southern Illinois were gaged with a V-notched weir and sampled with an automatic water sampler. For three years data were collected on flow volume and water quality. Flow volumes show large variations between years and watersheds. Samples were analyzed for Na+, K+, Ca++, Mg++, P, and NO-3. Water quality was consistently high, although there were significant differences between watersheds. A baseline for water quality has been established for comparison after one of the watersheds is clearcut at a later date.  相似文献   
87.
吨量煤体的自燃过程实验模拟研究   总被引:4,自引:0,他引:4  
为更好地弄清矿井实际的煤自然发火规律,利用装煤量达5吨的大型实验台对两种烟煤分别进行了自燃模拟实验。大煤量的实验能够很好地模拟煤矿中煤低温氧化和传热传质共同作用导致的发火过程,实验得到的自然发火期与煤矿实际发火期也是一致的。实验中煤样从缓慢氧化变为快速氧化的临界温度为100~110℃。当煤温低于,临界温度时,煤样的升温受到空气流带走热量和向外界散热的影响很大,因此夹层水的保温作用就很关键。当煤温超过临界温度后,反应加快,温度急剧上升,散热的影响明显降低,反应主要受限于氧气的供应情况。  相似文献   
88.
A global trend of a warming climate may seriously affect species dependent on sea ice. We investigated the impact of climate on the Baltic ringed seals (Phoca hispida botnica), using historical and future climatological time series. Availability of suitable breeding ice is known to affect pup survival. We used detailed information on how winter temperatures affect the extent of breeding ice and a climatological model (RCA3) to project the expected effects on the Baltic ringed seal population. The population comprises of three sub-populations, and our simulations suggest that all of them will experience severely hampered growth rates during the coming 90 years. The projected 30 730 seals at the end of the twenty-first century constitutes only 16 % of the historical population size, and thus reduced ice cover alone will severely limit their growth rate. This adds burden to a species already haunted by other anthropogenic impacts.  相似文献   
89.
Between May 1987 and November 1988, 505 early amniocentesis within the 15th week of gestation were performed at the First Department of Obstetrics and Gynaecology,‘L. Mangiagalli’ of the University of Milan and at the Department of Obstetrics and Gynaecology of ‘Gaslini’ hospital in Genoa. A total number often abnormal fetal karyotypes were diagnosed. In addition, one case of pseudomosaicism (not confirmed on fetal blood) and one case of osteogenesis imperfecta type II (observed at ultrasound examination) were also detected. Eleven pregnancies were therefore terminated because of an abnormal fetus. Out of 494 pregnancies (excluding terminated pregnancies) there were 16 fetal losses within the 28th week; ten of these occurred in the 2 weeks following the procedure. There were 475 live-births, of which 447 were term deliveries and the other 28 deliveries occurred before the 37th week of gestation.  相似文献   
90.
Science–policy interfaces are avenues for finding solutions for environmental challenges through strengthening collaborations between research disciplines and public administrations. Here we present a methodology for the conduct of science–policy interfaces between scientists and policymakers for addressing day-to-day environmental problems in the southeastern Spanish drylands. A knowledge brokering approach based on six consecutive workshops was used to facilitate mutual understanding and trust between scientists and policymakers. Water policy and biodiversity loss were identified as major environmental concerns in the region, and 12 final environmental problems were agreed as priorities. A graphical tool was used for diagnosing each environmental problem according to the available scientific knowledge, the current regulatory capacity of administrations, and the level of public engagement necessary for addressing the problem. The use of the graphical tool also allowed for (a) the clarification of roles involved in problem solving, and (b) the promotion of a culture of shared responsibility for the implementation of management actions based on collaborative work. We discuss lessons learned and propose recommendations for future experiences.  相似文献   
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