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101.
为防止盾构隧道行车道发生火灾时烟气侵入人员疏散通道,可通过在盾构隧道疏散通道内设置独立机械加压送风系统保证疏散通道内正压状态进行防烟,提高人员疏散安全性。分别利用风速法和压差法对某隧道工程疏散通道加压送风系统送风量进行试算,并采用FDS(Fire Dynamics Simulator)软件对疏散前室送风、疏散通道单侧送风及疏散通道双侧送风3种加压送风方式进行模拟分析,对比不同加压送风方式下各疏散口风速、温度、能见度的情况。结果表明,通过风速法计算得到的加压送风量要大于压差法。采用前室加压送风会造成较强的气流扰动,导致疏散口附近风速及温度剧烈波动,部分烟气进入前室,不利于人员疏散。采用疏散通道加压送风时,疏散口处风速稳定。但采用单侧加压送风时,火源下游疏散口处会有部分烟气积聚,影响人员疏散。采用双侧加压送风时烟气积聚少,疏散口附近温度、能见度等安全指标均在临界范围内,防烟效果良好,可以保证人员疏散安全。因此,建议采用纵向疏散通道加压送风,送风量建议采用风速法计算,当采用纵向疏散通道双侧加压送风时,建议在风速法得出的送风量基础上增加10%作为安全值。 相似文献
102.
Development of urban planning guidelines for improving emergency response capacities in seismic areas of Iran 总被引:1,自引:0,他引:1
Kambod Amini Hosseini Mohammad Kazem Jafari Maziar Hosseini Babak Mansouri Solmaz Hosseinioon 《Disasters》2009,33(4):645-664
This paper presents the results of research carried out to improve emergency response activities in earthquake-prone areas of Iran. The research concentrated on emergency response operations, emergency medical care, emergency transportation, and evacuation—the most important issues after an earthquake with regard to saving the lives of victims. For each topic, some guidelines and criteria are presented for enhancing emergency response activities, based on evaluations of experience of strong earthquakes that have occurred over the past two decades in Iran, notably Manjil (1990), Bam (2003), Firouz Abad-Kojour (2004), Zarand (2005) and Broujerd (2006). These guidelines and criteria are applicable to other national contexts, especially countries with similar seismic and social conditions as Iran. The results of this study should be incorporated into comprehensive plans to ensure sustainable development or reconstruction of cities as well as to augment the efficiency of emergency response after an earthquake. 相似文献
103.
为提高复杂连体宿舍楼的火灾应急疏散效率,以某高层连体复杂宿舍楼为例,运用PyroSim对该复杂连体宿舍楼发生火灾时的烟气蔓延特性以及不同楼体之间的相互影响进行模拟,运用Pathfinder对该宿舍楼的人员疏散进行仿真模拟。火灾模拟结果表明:连体宿舍楼中,连廊对整栋楼的安全至关重要,建议加强对连廊的消防管理。疏散模拟结果表明:中间连廊保持正常通行可以有效提高疏散效率;连体复杂宿舍楼不适合男女混住,应该根据建筑物结构合理安排居住人员;增加2~3层连廊,并设置可移动式外挂楼梯,同时确保发生紧急事故时应急疏散指导人员正确快速地引导人员进行疏散,可以有效提高疏散效率。研究方法和结果可为复杂连体宿舍楼的消防措施、建筑设计以及宿舍楼应急管理提供参考和借鉴。 相似文献
104.
"鸟巢"演唱会人员疏散CA-BP仿真研究 总被引:1,自引:0,他引:1
针对现今大型活动中的人群踩踏事故频发问题,通过对"鸟巢"演唱会进行人流疏散仿真分析,研究紧急情况下人流疏散逃生规律及均衡疏散方法.通过设置人员速度、移动余值、出口逃生条件等因素扩展元胞自动机行人流模型,并借助Matlab语言实现可视化仿真模拟,以探究人流疏散逃生规律;引入疏散系数,并通过建立BP神经网络获取较优疏散系数,均衡各个出口所承担的疏散任务.结果表明,"鸟巢"演唱会在疏散过程中人群对通行出口的选择较为不合理,仿真疏散总时间长达455.5 s,与理想疏散曲线所得疏散总时间270.0s相比,存在40.7%的偏差,为减小此偏差引入出口疏散系数指导人群定向选择出口,通过仿真模拟得到的疏散总时间为312.0 s,减少约31.5%,出口选择不均衡现象被显著缓解.最后提出了针对疏散不平衡问题的相关措施. 相似文献
105.
Benxiang Zeng 《Journal of Environmental Planning and Management》2015,58(2):270-282
Culling feral camels will impact on the carbon emissions from them. Culling of feral camels stops their long-term continuous methane emission, but emits carbon from their carcasses in the short term. Through on-site monitoring of the decomposition process of camels that have been shot dead, this paper models the pattern of carbon emissions during the decomposition of these camels in Central Australia, and analyses the contribution of the camel culling programme to carbon emission mitigation on the rangelands. A ‘carbon royalty’ payment mechanism is also suggested to encourage local participation in carbon markets through an involvement in natural resource management. 相似文献
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110.
Julia Ohl Alexander Wezel Glenn H. Shepard Jr. Douglas W. Yu 《Environment, Development and Sustainability》2008,10(6):827-843
In this study, we investigate whether traditional swidden agriculture on nutrient-poor tropical soils can sustainably support
a growing indigenous population within Manu National Park, Peru. Based on interviews with 50 Matsigenka farmers, as well as
GPS mapping and field visits, we established the location and size of all 124 swidden gardens cultivated in 2000 and 2001.
Using a GIS-based soil map of Manu Park, we identify the total extent of potential arable land (1) throughout the park zones
currently available for Matsigenka habitation, and (2) within the vicinity of the two study communities. Taking into account
current per capita garden size, cultivation and fallow practices, we calculate the maximum human carrying capacity of swidden
agriculture for (1) all available park zones and (2) the immediate vicinity of the two current communities. Even given the
second, highly limited scenario, the sustainable human carrying capacity is estimated to be 2,138 individuals, which is far
higher than the current population of about 420 people. Thus, arable land does not appear to be a limiting factor for the
growth of the indigenous population in Manu Park at the current time. Other possible limiting factors for population growth
are identified and discussed. We conclude that a conservation policy of population stabilization around the current settlements
is viable in that it will not result in reduced resource availability over the next few decades, and that the challenge is
to identify and mitigate the forces causing population fissioning and spread.
Readers should send their comments on this paper to BhaskarNath@aol.com within 3 months of publication of this issue. 相似文献