大型体育产业综合体消防设计与火灾风险评估

针对体育建筑发展趋势,调研分析了大型体育产业综合体存在的消防难点问题,给出了基本的解决方法。以某大型体育产业综合体为例,运用最不利原则设定火灾场景,利用烟气运动模型和人员疏散模型模拟分析了综合体内烟气蔓延情形和人员疏散状况,通过比较可用安全疏散时间与必需安全疏散时间,得出在消防措施失效时无法保证人员安全疏散的结论,并针对性地提出了积极可行的消防加强措施。     

以性能为基础的某大型高架仓库消防安全评估

高架仓库空间大、物品堆积密集,火灾危险性大,并且高架仓库设计朝着大面积、大空间的方向发展,当前的防火设计规范已不能满足现代高架仓库的消防安全设计。以某高架仓库的消防设计为例,分析其火灾危险性,提出了以性能为基础的消防设计评估方法,结合该仓库的具体情况进行火灾场景设计。火灾烟气流动模拟和人员疏散模拟结果表明：在消防设施正常启动的条件下,仓库现有的安全措施能够保证火灾时人员的安全疏散。     

排烟系统ASET预测结果性能化评估

在性能化设计评估中,需要通过火灾烟气模拟的方法来预测人员可用的安全疏散时间,而设计火灾场景时排烟系统的情况设置对预测结果有很大影响。以某商业防火分区中庭排烟系统是否失效来研究这个问题,从而进一步说明排烟系统正常工作对保证人员安全疏散的重要性。     

高铁站房大空间高架候车层消防设计

以某高铁站房高架候车层为例,针对站房内高架候车层大空间结构设计不符合国家现行消防标准的情况,提出将“燃烧岛”、“防火舱”等概念用于大空间高架候车层消防设计的思路.通过多种火灾场景及疏散场景的设定,利用FDS模拟烟气蔓延、利用Pathfinder模拟人员疏散的方法验证了其消防设计方案的可行性,为“燃烧岛”、“防火舱”等概念用于大空阃消防设计提供借鉴.     

某美食城性能化防火设计研究

针对某美食城防火分区面积过大、疏散距离过长和钢结构防火保护的问题,提出了性能化防火设计。设定火灾场景,模拟各部分人员的疏散时间;以FDS软件模拟烟气运动,得到可用疏散时间,经过分析,各场景下均能安全疏散。采用经验公式计算和FDS模拟分析两种方法计算火灾环境中钢构件的温度,提出了钢结构的保护方案。     

公共场所人员消防安全疏散模拟系统设计

公共场所的人员消防安全疏散问题是确保火灾下人员生命安全的关键.为模拟公共场所人员的消防安全疏散行为,提出了一种基于元胞自动机的火灾情况下人员疏散模型.在详细的系统需求分析、概要设计和详细设计基础上,开发了公共场所人员消防安全疏散模拟系统,并进行了系统测试和火灾情况下人员疏散过程模拟.该系统实现了生成公共场所火灾场景、计算并模拟人员疏散行为、管理消防安全疏散规范及算法等功能,系统运行稳定,对人员疏散的模拟过程与实际相符,具有操作简单、模拟直观、数据可靠、扩张性强等特点,能够为研究火灾环境下公共场所人员安全疏散问题提供平台.     

某大型商业综合体建筑安全疏散性能化消防设计探析

对选定的大型商业综合体建筑功能特点及防火设计问题进行分析,运用消防安全工程学原理,选择适当的分析方法,采用可靠的技术手段和分析软件,设定全面客观的火灾与疏散场景,对烟气流动和人员疏散进行模拟分析.在对该项目拟定的消防设计方案进行调整并设置必要的消防设施保障后,能达到性能化设计提出的保证人员生命安全和限制火灾大规模蔓延的设计目标.     

商业综合体室内步行街烟气控制措施有效性数值模拟研究

以实现商业综合体室内步行街＂准安全区＂为目标,对自然排烟和机械排烟两种烟气控制措施的有效性进行数值模拟研究。采用FDS和Building-Exodus模拟方法,在两种烟气控制措施下分别计算商业综合体室内步行街内的危险临界值TASET和人员安全疏散需要时间TRSET。研究结果表明：适当的烟气控制措施是＂准安全区＂实现的充分条件,在同等条件下,自然排烟的有效性优于机械排烟。计算结果表明,自然排烟面积与排烟效果成正比。研究证明,若将自然排烟和机械排烟相结合,可以有效应对火灾时多种不利情况,增强排烟的可靠性。     

大型商业综合体内影院消防设计探讨

重点介绍了某大型商业综合体内影院的消防设计方案,并进行烟气流动和人员疏散的数值模拟分析,得出该影院消防设计是安全可行的.为确保此类影院的消防安全,建议其疏散楼梯设计不受商场营业与否的影响,且应定期维护保养消防系统.     

消防应急照明和疏散指示标志设置常见问题分析

消防应急照明与疏散指示标志的作用是保证火灾时仍需坚持工作场所的工作照度和安全通道的疏散照度,正确引导火灾场所的人员安全疏散到安全地带,是保障消防作业和安全疏散必不可少的重要设施。消防应急照明和疏散指示标志的设置应既符合消防要求又要行之有效,但在实际工作中经常出现设置上的疏漏和错误,下面就一些常见的问题进行列举分析。     

The search for an intelligent evader concealed in one of an arbitrary number of regions

This paper considers the search for an evader concealed in one of an arbitrary number of regions, each of which is characterized by its detection probability. We shall be concerned here with the double-sided problem in which the evader chooses this probability secretly, although he may not subsequently move; his aim is to maximize the expected time to detection, while the searcher attempts to minimize it. The situation where two regions are involved has been studied previously and reported on recently. This paper represents a continuation of this analysis. It is normally true that as the number of regions increases, optimal strategies for both searcher and evader are progressively more difficult to determine precisely. However it will be shown that, generally, satisfactory approximations to each are almost as easily derived as in the two region problem, and that the accuracy of such approximations is essentially independent of the number of regions. This means that so far as the evader is concerned, characteristics of the two-region problem may be used to assess the accuracy of such approximate strategies for problems of more than two regions.     

智能工具机的性能分析

本文论述了提高智能工具机性能所采取的技术措施,并对其性能进行了模拟。模拟结果表明,智能工具机的平均推理速度可达500KLIPS 左右,比日本的PSI—Ⅰ约快一倍,比美国加州大学Berkeley 分校研制的PLM 约快两倍。     

Properties of an approximate hazard transform

The calculation of the exact reliability of complex systems is a difficult and tedious task. Consequently simple approximating techniques have great practical value. The hazard transform of a system is an invertible transformation of its reliability function which is convenient and useful in both applied and theoretical reliability work. A simple calculus for finding an approximate hazard transform for systems formed by series and parallel combinations of components is extended so that it can be used for any coherent system. The extended calculus is shown to lead to conservative approximations. A first order version of the extended calculus is also discussed. This method of approximation is even more simple to use, but is not always conservative. Examples of its application indicate that it is capable of giving quite accurate results.     

Strategy selection: an info-gap methodology

The evaluation and selection of military strategy requires consideration of myriad factors – social, historical, political, geographical and technological – together with vast uncertainties encompassing all these domains. Info-gap decision theory is a conceptual framework that can support these deliberations and that has substantive implications for the formulation, evaluation and selection of strategic goals and of the means to attain them. In particular, while the analyst may desire to reliably achieve the best possible outcome, info-gap theory provides a critique of, and alternative to, the paradigm of optimizing the outcome of a decision. In selecting between strategy alternatives, the analyst must sometimes choose between one alternative that is purportedly better than another, but also more uncertain. Such a choice is a dilemma whose resolution requires the analyst to balance between the different predicted qualities of each alternative and their different vulnerabilities to uncertainty. The dilemma can be managed with the info-gap methodology of robustly satisfying critical requirements.     

汽车发动机舱主线束短路火灾研究

对一起越野型汽车火灾事故进行深入调查和技术鉴定,认定火灾原因为发动机舱主线束短路引发.在案例分析的基础上,进一步剖析了此类汽车发动机舱主线束引起火灾的危险性,分析其在设计中存在的火灾隐患,提出几点改进的建议.     

More on the search for an infiltrator

We have asymptotically solved a discrete search game on an array of n ordered cells with two players: infiltrator (hider) and searcher, when the probability of survival approaches 1. The infiltrator wishes to reach the last cell in finite time, and the searcher has to defend that cell. When the players occupy the same cell, the searcher captures the infiltrator with probability 1 ? z. The payoff to the hider is the probability that the hider reaches the last cell without getting captured. © 2002 John Wiley & Sons, Inc. Naval Research Logistics, 49: 1–14, 2002; DOI 10.1002/nav.1047     

Scheduling policies for an antiterrorist surveillance system

This article concerns scheduling policies in a surveillance system aimed at detecting a terrorist attack in time. Terrorist suspects arriving at a public area are subject to continuous monitoring, while a surveillance team takes their biometric signatures and compares them with records stored in a terrorist database. Because the surveillance team can screen only one terrorist suspect at a time, the team faces a dynamic scheduling problem among the suspects. We build a model consisting of an M/G/1 queue with two types of customers—red and white—to study this problem. Both types of customers are impatient but the reneging time distributions are different. The server only receives a reward by serving a red customer and can use the time a customer has spent in the queue to deduce its likely type. In a few special cases, a simple service rule—such as first‐come‐first‐serve—is optimal. We explain why the problem is in general difficult and we develop a heuristic policy motivated by the fact that terrorist attacks tend to be rare events. © 2009 Wiley Periodicals, Inc. Naval Research Logistics, 2009