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101.
浅论建筑消防安全性能化评估技术   总被引:5,自引:1,他引:5  
建筑消防安全性能化设计以其灵活性、科学性、经济性和有效性等优点受到了国际社会越来越多的重视,并在很多国家得到了应用。性能化评估作为性能化设计的核心环节,直接关系到性能化设计方案的成败。如何进行性能化评估,如何对性能化设计方案的评价和论证,如何设定相应的消防安全性能评估程序等等问题,都值得深入探讨。从建筑消防安全性能化设计的优点及其评估的重要性入手,从性能化评估的作用和必要性出发,深入分析了建筑消防安全性能化评估与性能化设计的关系;探讨了建筑消防安全性能化评估的步骤、流程、判定标准及其量化指标;并对国际上常用于性能化评估的3种典型的火灾风险评估模型进行了详细对比分析,并提出了进行性能化评估时需注意的一些关键问题。  相似文献   
102.
事物安全演化过程的基本理论研究   总被引:1,自引:1,他引:1  
安全状态的演化过程是事物发展变化过程的重要组成部分.事物的安全演化过程符合从量变到质变的原理,即服从"安全流变-突变"规律.基于事物"安全流变-突变"规律,建立理论模型,并分析和描述事物的安全演化过程.事物"安全流变-突变"规律的研究为揭示事物的安全本质规律奠定了基础.  相似文献   
103.
旅游区(点)安全评估体系初探   总被引:1,自引:0,他引:1  
旅游区的安全状况越来越受到各级政府的广泛关注,规范旅游景点安全管理已成当务之急.文章以模糊数学和层次分析理论为指导构建了旅游区(点)安全评估指标体系和评价模型,评价过程考虑了影响安全等级的相关因素,并保留了各级评价的全部信息.实例采用典型的旅游景点指标数据,评价结果直观地反映了旅游区的安全状况.  相似文献   
104.
道路交通安全管理措施比较研究   总被引:6,自引:1,他引:6  
根据近五年来我国道路交通安全状况的实际,针对目前我国道路交通安全管理的现状,本文就道路交通法规建设、道路交通安全宣传教育、道路交通执法、道路事故紧急救援措施等相关内容与日本、美国、欧洲交通发达国家进行了对比分析,以图找出我国现行的道路交通安全管理对策中的薄弱环节及完善的途径.  相似文献   
105.
通风系统安全可靠性评价研究与实现   总被引:3,自引:0,他引:3  
矿井通风系统可靠性评价应能及时反映矿井通风系统可靠性的高低,为矿井通风系统的决策者提供有意义的信息,根据信息及时调整矿井通风系统,解决系统中存在的重大安全问题。准确、及时、可靠的数据信息是矿井通风系统安全部门进行技术管理和防灾救灾的重要依据,也是矿井通风系统可靠性评价的重要组成部分。在可靠性分析的基础上提出了矿井通风系统可靠性评价设计思想和软件的实现方法。  相似文献   
106.
The Japanese government is planning to introduce DME as a substituted energy for oil and LNG. Introduction of DME could contribute greatly to both the prevention of global warming and the formation of resource-recycling societies. In these circumstances, a safety assessment of DME is very important when DME is used on a large scale. There is a possibility that prolonged exposure in air induces autoxidation to produce explosive organic peroxides during transportation and storage of DME. Therefore, the reactivity of DME with oxygen and the mechanism of the autoxidation were investigated. Accelerating Rate Calorimetry (ARC) was used to evaluate the thermal stability of DME and DIPE, a known peroxide producers, under adiabatic and various atmospheric conditions. In ARC studies of DME under oxygen, exothermic decompositions were detected although its self-heating rate was low in comparison with DIPE. Oven storage tests were carried out and iodimetry was used to measure the concentration of peroxides produced from DME in comparison with DIPE and DEE. However, no products could be found for DME either by GC/MS or by iodimetry, while some evidence of autoxidation of both DEE and DIPE were obtained from these experiments.  相似文献   
107.
Stream restoration projects are often based on morphological form or stream type and, as a result, there needs to be a clear tie established between form and function of the stream. An examination of the literature identifies numerous relationships in naturally forming streams that link morphologic form and stream processes. Urban stream restoration designs often work around infrastructure and incorporate bank stabilization and grade control structures. Because of these imposed constraints and highly altered hydrologic and sediment discharge regimens, the design of urban channel projects is rather unclear. In this paper, we examine the state of the art in relationships between form and processes, the strengths and weaknesses of these existing relationships, and the current lack of understanding in applying these relationships in the urban environment. In particular, we identify relationships that are critical to urban stream restoration projects and provide recommendations for future research into how this information can be used to improve urban stream restoration design. It is also suggested that improving the success of urban restoration projects requires further investigation into incorporating process-based methodologies, which can potentially reduce ambiguity in the design and the necessity of using an abundant amount of in-stream structures.  相似文献   
108.
陈安  周丹 《安全》2019,40(7):16-23
本文为了增加对突发事件的科学认识,提升应急管理的能力水平,首先对突发事件和应急管理的内在机理进行剖析。通过分阶段、划层次地构建"4L-5S"机理分析模型,将二者划归为统一体系,以理清其逻辑内涵;然后,为顺应时代发展特征,满足应急管理的更高要求,实现应急管理工作从非常态协同应对转为常态化职能管理,对现代应急管理体制加以总体设计。从而,突发事件机理体系设计使得我国的突发事件机理研究逐渐过渡至具有阶段性和层次性,现代应急管理体制设计使得我国应急管理整合出具备现代思维理念的逻辑框架。  相似文献   
109.
Natural scientists are increasingly interested in social research because they recognize that conservation problems are commonly social problems. Interpreting social research, however, requires at least a basic understanding of the philosophical principles and theoretical assumptions of the discipline, which are embedded in the design of social research. Natural scientists who engage in social science but are unfamiliar with these principles and assumptions can misinterpret their results. We developed a guide to assist natural scientists in understanding the philosophical basis of social science to support the meaningful interpretation of social research outcomes. The 3 fundamental elements of research are ontology, what exists in the human world that researchers can acquire knowledge about; epistemology, how knowledge is created; and philosophical perspective, the philosophical orientation of the researcher that guides her or his action. Many elements of the guide also apply to the natural sciences. Natural scientists can use the guide to assist them in interpreting social science research to determine how the ontological position of the researcher can influence the nature of the research; how the epistemological position can be used to support the legitimacy of different types of knowledge; and how philosophical perspective can shape the researcher's choice of methods and affect interpretation, communication, and application of results. The use of this guide can also support and promote the effective integration of the natural and social sciences to generate more insightful and relevant conservation research outcomes. Una Guía para Entender la Investigación de Ciencias Sociales para las Ciencias Naturales Katie Moon  相似文献   
110.
Environmental heterogeneity is increasingly being used to select conservation areas that will provide for future biodiversity under a variety of climate scenarios. This approach, termed conserving nature's stage (CNS), assumes environmental features respond to climate change more slowly than biological communities, but will CNS be effective if the stage were to change as rapidly as the climate? We tested the effectiveness of using CNS to select sites in salt marshes for conservation in coastal Georgia (U.S.A.), where environmental features will change rapidly as sea level rises. We calculated species diversity based on distributions of 7 bird species with a variety of niches in Georgia salt marshes. Environmental heterogeneity was assessed across six landscape gradients (e.g., elevation, salinity, and patch area). We used 2 approaches to select sites with high environmental heterogeneity: site complementarity (environmental diversity [ED]) and local environmental heterogeneity (environmental richness [ER]). Sites selected based on ER predicted present‐day species diversity better than randomly selected sites (up to an 8.1% improvement), were resilient to areal loss from SLR (1.0% average areal loss by 2050 compared with 0.9% loss of randomly selected sites), and provided habitat to a threatened species (0.63 average occupancy compared with 0.6 average occupancy of randomly selected sites). Sites selected based on ED predicted species diversity no better or worse than random and were not resilient to SLR (2.9% average areal loss by 2050). Despite the discrepancy between the 2 approaches, CNS is a viable strategy for conservation site selection in salt marshes because the ER approach was successful. It has potential for application in other coastal areas where SLR will affect environmental features, but its performance may depend on the magnitude of geological changes caused by SLR. Our results indicate that conservation planners that had heretofore excluded low‐lying coasts from CNS planning could include coastal ecosystems in regional conservation strategies.  相似文献   
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