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691.
建筑物火灾疏散中人的行为研究的回顾与发展   总被引:19,自引:4,他引:15  
建筑物发生火灾后 ,安全疏散所需时间的长短主要取决于疏散开始时间 ,疏散开始时间又取决于人的行为 ,而人的行为是其生理和心理因素的函数。为此 ,在论证研究人的行为在疏散评价的重要性的基础上 ,详细地评述了火灾疏散中人行为的历史背景、研究内容和研究范围 ,然后展望了其以后的研究方向。特别强调 ,基础数据库的收集与建立、人行为的模式、系统动态的模拟和仿真等在研究中的重要作用  相似文献   
692.
Reducing the negative impact from on-site systems and promoting recycling are important tasks for municipal authorities, especially as regards phosphorus. The objective of this scenario study was to compare energy turnover in a life cycle perspective, recycling potential and expected reduction of nitrogen and phosphorus emissions for three upgraded small-scale wastewater systems based on local recycling of plant nutrients. The systems studied were urine separation, blackwater separation and chemical precipitation in the septic tank. The urine was sanitised through storage, the blackwater through liquid composting and the precipitated sludge through chemical treatment with urea before reuse in agriculture. The system boundaries included the operational phase as well as investment in capital goods required for upgrading the existing on-site systems.The urine separation system used least energy. The potential recycling and reduction of phosphorus was lower than for the other two systems, while that of nitrogen was higher than for the chemical precipitation system but lower than for the blackwater separation system. The blackwater separation system reduced both nitrogen and phosphorus to a high extent and also enabled a large proportion of both nitrogen and phosphorus to be recycled to arable land. However, a major drawback with this system was its significantly higher use of electricity, related to the aeration and stirring required when sanitising the blackwater by liquid composting. When urea treatment replaced liquid composting, the use of electricity decreased substantially in the blackwater separation system. The chemical precipitation system was efficient in reducing and recycling phosphorus, while inefficient for nitrogen. The use of fossil fuels was significantly higher than for the other two systems, primarily due to the production of the precipitation chemical.  相似文献   
693.
探讨了人机系统中人为失误与不同应激的相关性.按照模糊集理论,根据成员功能结构,提出了定义正常应激范围的方法以及过高过低应激导致的事故等不良后果.  相似文献   
694.
This study reports on the quantification of horizontal erosion by undermining of slopes in the atlantic mesotidal salt marshes of Odiel, SW Spain, and analyses its causes and consequences. Horizontal erosion has produced considerable losses of salt marsh area, including zones of mature salt marsh. Human pressure, such as from water-borne traffic or the exploitation of the slopes for the capture of bait, increases the natural erosion processes. The role of vegetation in protecting the slopes against erosion is studied. Channel banks covered with plants, many of which belong to species with long-living, above-ground creeping stems, were less eroded than those without vegetation cover. The enormous volume of sediments moved (ca. 7000m3 in one year) could contribute to the silting-up of the navigable channels of the estuary, so that continual dredging is necessary to allow access to shipping. These sediments are highly contaminated, and dredging exposes them more directly to the trophic network of the estuary. There is a considerable loss of natural resources. Finally, the integrated management of this coastal ecosystem is discussed.  相似文献   
695.
This study presents concentration of nine minerals (Na, K, Mg, Ca, Cl, Mn, Zn, Cd, Pb) in 31 drinking water samples collected in the Papua New Guinea lowland, where coastal villagers draw water from artificial wells blended with sea water, riverside villagers utilize brackish river water, and inland villagers fetch creek or swamp water whose chemical composition is close to rain water. During the dry season, the coastal well water contains 500 mgL−1 of sodium and 50–90 μgL−1 of lead. The inland creek or swamp water contains very small amount of minerals; on the average, for instance, 0.64 mgL−1 of magnesium, 0.84 mgL−1 of calcium, and 4.78 mgL−1 of water hardness (as CaCO3). From some epidemiological evidence in industrialized countries, these mineral concentrations are judged to be indicative of high risk of cardiovascular disorders.  相似文献   
696.
Ecological planning: A review   总被引:4,自引:0,他引:4  
Beginning with the passage of the National Environmental Policy Act in 1969, the federal government of the United States has enacted numerous pieces of legislation intended to protect or conserve the environment. Other national governments have also enacted environmental legislation during the past two decades. State and local governments have also adopted policies concerned with environmental planning and management. Multiple laws and overlapping governmental agency responsibilities have confused development and resource management efforts. A comprehensive methodology that integrates the legal mandates and the agency missions into a common and unified framework is needed. Ecological planning offers such a method. Application of the method allows planners and resource managers to better understand the nature and character of the land and/or resource and therefore make better decisions about its appropriate use or management. The steps taken in an ecological planning process—1) goal setting, 2) inventory and analysis of data, 3) suitability analysis, 4) developing alternatives, 5) implementation, 6) administration, and 7) evaluation—are outlined and explained. Hand-drawn overlays and computer programs as techniques for handling ecological planning information are compared. Observations and suggestions for further research are offered.  相似文献   
697.
河北省地质地貌灾害与防灾减灾   总被引:2,自引:0,他引:2  
商彦蕊 《灾害学》1999,14(1):33-38
河北省是我国地质地貌灾害最为严重的地区之一.本文从人类生态学角度,研究地质地貌灾害的成因与分布,并强调通过调整人类活动,减轻灾害损失和影响.  相似文献   
698.
人为失误原因分析与控制对策研究   总被引:11,自引:1,他引:11  
研究了人为失误对系统安全的影响,分析了人为失误产生的原因及其影响因素,并就煤矿安全管理中人为失误的控制提出了针对性措施  相似文献   
699.
Meyer MA 《Disasters》1984,8(4):302-306
This paper examines the various legal constraints upon action by relief workers when faced with violations of human rights or of humanitarian law. The unique status of the International Committee of the Red Cross (ICRC) and its delegates is explained and contrasted with the position of relief organizations and their personnel under the Geneva Conventions 1949 and their Additional Protocol I 1977. Proposals are made for the establishment of guidelines for action by relief workers when confronted with atrocities and for the training of relief workers in the relevant laws and procedures.  相似文献   
700.
室内甲醛污染及对人体健康的影响   总被引:4,自引:0,他引:4  
通过对三种不同类型居室内甲醛监测表明,甲醛浓度与室内装饰、吸烟和燃料的不完全燃烧有关.兰州地区夏季室内甲醛超标率高,为41.0%~51.3%.室内主要污染物除TSP以外,甲醛居第2位,且一天中浓度最高值在中午.新建居室比普通居室甲醛浓度高,在所有情况下,室内浓度高于室外.  相似文献   
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