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541.
大空间建筑内火灾烟气充填的研究   总被引:7,自引:1,他引:7  
对烟气在大空间建筑内的充填规律作了分析,并在中国科技大学与香港理工大学合建的大空 间火灾实验厅内进行了若干轮试验。结果表明,在着火的初期阶段,大厅上部的烟气流动比较紊 乱,但在以后的大部分时间,烟气的充填过程仍可用火灾区域模拟方法计算。  相似文献   
542.
Miles SB  Green RA  Svekla W 《Disasters》2012,36(3):365-381
This study presents findings of an institutional capacity analysis of urban disaster risk reduction for informal settlements in the Guatemala Metropolitan Region. It uses a resource access perspective of vulnerability, actor-network theory, and qualitative data collection. The analysis reveals that there is interest in disaster risk reduction for the informal settlements; however, there is little in the way of direct financial or oversight relationships between informal settlement residents and all other actors. Respondents observed that informal settlements would probably remain inhabited; thus, there is a need for disaster risk reduction within these settlements. Disaster risk reduction capacity for informal settlements exists and can be further leveraged, as long as steps are taken to ensure appropriate access to and control of resources and oversight. Further, the nascent institutional arrangements should be strengthened through increased communication and coordination between actors, a decentralization of oversight and financial relationships, and mediation of identified resource conflicts.  相似文献   
543.
利用城镇地籍数据信息,基于GIS软件进行建筑物易损性和居民安全风险分析与应用研究。通过对某县城中最具代表性的一个街坊建筑物的易损性分析和居民安全风险分析实例应用研究,重点讨论并实现了利用现有数字化地籍图、城镇地籍数据库及土地调查记录等信息;并结合建筑物震害损失评估模型和人员伤亡预测方法,完成不同结构类型的建筑物在不同地震烈度条件下的破坏造成的经济损失评估和人员伤亡程度的预测,对城市防灾减灾进行辅助决策支持与评估。  相似文献   
544.
高层隔震结构的分析理论和设计方法是目前隔震技术向高层建筑推广的2个关键理论问题。本文以高烈度区宿迁市已经竣工的高层隔震建筑阳光大厦为工程实例,对高层隔震结构的非线性地震响应分析方法进行了研究,包括隔震支座竖向不同拉压刚度的模拟、各种类型的隔震支座水平力学特性的准确模拟,以及不同地震动输入方式和输入角度对隔震支座受拉情况的影响分析等;在此基础上,对隔震层的设计方法进行了分析,提出了隔震层设计的基本原则,进而给出了控制隔震层设计的基本指标,包括隔震支座的长期面压、极值面压、隔震层偏心率等;最后,对高层隔震结构的相关构造要求进行了必要的说明。  相似文献   
545.
依据环境监测能力建设标准,提出了"十二五"期间基层监测站能力建设的目标和要求,指出实现"三个说得清",应以科研工作为先导,以污染防治为核心,以信息化建设为载体,强化对环境质量综合分析和环境风险源筛分排查,充分发挥基层监测站的作用,更好地为环境管理提供准确有效技术支持的建设思路.  相似文献   
546.
Conservation technology holds the potential to vastly increase conservationists’ ability to understand and address critical environmental challenges, but systemic constraints appear to hamper its development and adoption. Understanding of these constraints and opportunities for advancement remains limited. We conducted a global online survey of 248 conservation technology users and developers to identify perceptions of existing tools’ current performance and potential impact, user and developer constraints, and key opportunities for growth. We also conducted focus groups with 45 leading experts to triangulate findings. The technologies with the highest perceived potential were machine learning and computer vision, eDNA and genomics, and networked sensors. A total of 95%, 94%, and 92% respondents, respectively, rated them as very helpful or game changers. The most pressing challenges affecting the field as a whole were competition for limited funding, duplication of efforts, and inadequate capacity building. A total of 76%, 67%, and 55% respondents, respectively, identified these as primary concerns. The key opportunities for growth identified in focus groups were increasing collaboration and information sharing, improving the interoperability of tools, and enhancing capacity for data analyses at scale. Some constraints appeared to disproportionately affect marginalized groups. Respondents in countries with developing economies were more likely to report being constrained by upfront costs, maintenance costs, and development funding (p = 0.048, odds ratio [OR] = 2.78; p = 0.005, OR = 4.23; p = 0.024, OR = 4.26), and female respondents were more likely to report being constrained by development funding and perceived technical skills (p = 0.027, OR = 3.98; p = 0.048, OR = 2.33). To our knowledge, this is the first attempt to formally capture the perspectives and needs of the global conservation technology community, providing foundational data that can serve as a benchmark to measure progress. We see tremendous potential for this community to further the vision they define, in which collaboration trumps competition; solutions are open, accessible, and interoperable; and user-friendly processing tools empower the rapid translation of data into conservation action. Article impact statement: Addressing financing, coordination, and capacity-building constraints is critical to the development and adoption of conservation technology.  相似文献   
547.
浅议建筑垂直绿化   总被引:4,自引:0,他引:4  
建筑垂直绿化是建筑景观设计及节能的重要内容,论文论述了建筑垂直绿化的作用、形式以及国内外应用案例,提出了不同建筑和墙面适用不同的绿化方式。通过软件计算对某住宅建筑采用垂直绿化后的能耗进行了分析。结果表明,采用墙面垂直绿化的建筑能耗明显低于无绿化建筑,最后对建筑垂直绿化的产业化发展和经济性进行了分析和展望。  相似文献   
548.
One of the primary adverse environmental impacts associated with power generation facilities and in particular thermal power plants is local air quality. When these plants are operated at inland areas the dry type cooling towers used may significantly increase ambient concentrations of air pollutants due to the building downwash effect. When one or more buildings in the vicinity of a point source interrupt wind flow, an area of turbulence known as a building wake is created. Pollutants emitted from relatively low level sources can be caught in this turbulence affecting their dispersion. In spite of the fact that natural gas-fired combined-cycle power plants have lower air emission levels compared to other power plants using alternative fossil fuel, they can still create significant local air pollution problems. In this paper, local air quality impacts of a natural gas-fired combined-cycle power plant located in a coastal area are compared with those of another natural gas-fired combined-cycle power plant having identical air emissions but located in an inland area taking into account differences in topography and meteorology. Additionally, a series of scenarios for the inland site have been envisaged to illustrate the importance of plant lay-out configurations paying particular attention to the building downwash effect. Model results showed that different geometrical configurations of the stacks and cooling towers will cause remarkable differences in ambient air pollutant concentrations; thus it is concluded that when selecting a plant site, a detailed site-specific investigation should be conducted in order to achieve the least possible ambient air pollution concentrations with the given emissions.  相似文献   
549.
针对高层建筑中常见的U型外立面结构,对典型有机保温材料硬质聚氨酯泡沫(PU)进行了小尺度条件下的U型结构竖直火蔓延实验研究,分析了其区别于高层建筑普通结构的竖直火蔓延特性.实验结果表明,U型结构竖直方向火蔓延是一个非稳态的火蔓延过程,其火蔓延速度会随着时间的推进逐渐加速.在燃烧过程中U型结构会产生烟囱效应,促进火蔓延的发展,其强度随着U型结构因子的增大而增大,当结构因子大于1.2时,火蔓延加速过程趋于稳定.  相似文献   
550.
为研究人员密集的连体型宿舍楼安全疏散问题,通过调查提出预先引导疏散的人员接受度原则,制定3种预先引导疏散策略,采用Pathfinder软件模拟某高校连体型宿舍楼的安全疏散情况,得出不采取预先引导疏散策略和采取不同预先引导疏散策略时,模拟疏散结果存在的差异。结果表明:人员可接受的预先引导疏散路径为最近距离路径或无视线阻碍的第2近距离路径;在不进行预先引导疏散时,疏散过程中各楼梯和出口的利用率差异较大;在进行预先引导疏散时,得出采用按楼梯宽度比例分区划分人数策略可有效提高建筑物的疏散效率。  相似文献   
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