烃类流体火灾伤害破坏作用定量分析

对烃类流体火灾的伤害破坏作用进行正确的定量分析是开展重大消防目标火灾风险评估工作的基础。针对烃类流体火灾伤害破坏作用定量分析中存在的问题,系统论述烃类流体火灾伤害破坏作用的定量分析方法,分析并讨论火球、池火、喷射火和蒸气云火灾等不同火灾形式的热辐射通量计算模型及其前提条件,对不同热辐射伤害破坏作用准则及伤害概率模型的适用条件和模型基础进行了论述。     

防火灾和毒气用自救呼吸器

一、火灾和毒气对人员的伤害机理 为有效防止或减少火灾和毒气事故造成人员伤亡,对火灾、毒气的伤害机理研究结果表明:     

火灾烟气伤害机理和伤害模型

建筑物发生火灾时，燃烧产生的烟气对人构成主要威胁。本文分析火灾烟气的伤害机理，提出烟气伤害指数概念及其计算方法，探讨它在材料防火性能评价和建筑物火灾安全评价方面的应用可能性。     

池火灾评价法在环氧乙烷罐区的应用研究

以某石油化工厂区为工程应用背景,通过对环氧乙烷储罐区计算模型的建立,应用池火灾评价法对环氧乙烷储罐发生池火灾的热辐射伤害区域进行了定量计算,得出环氧乙烷罐区发生池火灾的各级影响半径和造成的伤害程度。结果表明,只有当人员撤离罐区67.35 m范围外方可避免受到热辐射伤害。从环氧乙烷罐区的整体安全性出发,提出了具体的防护措施和建议,为企业的安全管理工作提供参考依据。     

油库火灾危害分析

运用“池火灾伤害模型”,对某油库汽油罐火灾危害程度进行分析,得出火灾危害程度与事故原点距离之间的关系,为油库安全运营提供参考。     

大型LPG罐区火灾爆炸事故后果评估

针对大型LPG(液化石油气)储罐区潜在的火灾爆炸危险性，建立了喷射火、火球、UVCE爆炸和BLEVE爆炸的数学伤害模型，对其发生火灾、爆炸后人员和建筑(设备)所受到的伤害和损伤进行了定量后果评估。     

家庭防火“十注意”

近年来,家庭火灾多发,给家庭财产和人民生命安全造成极大伤害。火灾原因集中于用电、用气,用火不慎,为此,提醒广大居民消防安全要做到“十注意”。     

DOW火灾爆炸指数评价法在天然气配气站安全评价中的应用

本文基于造成火灾爆炸的原因进行了分析,运用DOW火灾爆炸指数评价法对某配气站进行了安全评价,得到该配气站的危险性等级以及伤害范围,提出建议措施。     

大巴车遭遇火灾如何逃生?

大巴车是人们出行时较为常用的交通工具之一。近年来,大巴车起火事故时有发生,一旦发生火灾,到底该如何逃生才能将伤害降到最低?火灾特点1.空间狭小,逃生困难车辆内部空间狭小,一旦发生火灾,如不及时逃离,将很可能被困车内。     

LPG喷射火灾危害的研究和分析

分析了LPG喷射火的形成原因及常见发生部位。提出分别以点源模型和固体火焰模型计算火灾热辐射,并比较了其优缺点。分析了喷射火对人员及设备的热辐射伤害效应。将火灾热辐射和热辐射伤害阈值结合起来,定量地分析LPG喷射火的危害及引发次生灾害的可能性,最后进行了实例计算分析。     

基于MATLAB图像处理的层流火焰传播速度研究

为了减小传统本生灯火焰法测定层流预混火焰传播速度的误差,基于MATLAB图像处理技术提出了一种改进火焰图像处理及提取火焰边界线数据的方法。该方法对图像进行优化处理后运用LOG算子检测边缘信息,并为其添加平滑曲线;然后将散点拟合为函数表达式,选用Polynomial逼近方式修正拟合曲线误差;换算为实际坐标后对拟合函数进行面积积分计算,即得更接近真实的火焰外表面积。利用该方法对不同当量比下甲烷燃烧的本生灯火焰图像进行处理,求取其层流火焰传播速度,并与前人结果进行对比。结果表明,传统全面积法所得结果普遍偏高;相比于Vagelopulous利用平面火焰法所得结果,该方法获取的层流火焰传播速度在贫燃侧与之相近,在富燃侧则较之略低。     

疏散路径受阻情况下的人员疏散模型及算法

建筑火灾中,随着火势的不断增大和烟气的不断增多,随时会有某条疏散路径因被火势或烟气封堵而不能正常通行的情况发生。针对此情况下的应急疏散问题,以待疏散人员全部完成疏散所需时间最短为目标,以结合疏散路径的通行能力合理分配待疏散人员为原则,运用Dijkstra算法对网络中的最短路径进行求解,并结合网络流控制的方法实现疏散人员的合理分配,建立了疏散路径受阻情况下的人员疏散模型,并提出了该模型的算法思想及算法步骤,最后结合算例进行了验证。验证结果表明,该模型及算法可行、有效,既可较好地避免因大量人员选择相同疏散路线而造成的拥堵,还提高了疏散网络的整体使用率,又有效缩短了人员的疏散所需时间。     

基于自适应遗传算法的应急物资储备库选址及物资调配优化研究

应急物资储备库是应急救援的重要载体,储备库选址是否科学合理决定着整个应急公共服务体系的成效,而传统遗传算法在研究储备库选址与物资调配相结合的问题上存在局限性。针对这一问题,从需求点及应急设施服务质量视角构建基于覆盖满意度和经济性的应急设施选址与物资调配优化模型,并根据模型设计自适应遗传算法(AGA),结合储备库实际情况采取具有方向性的初始群体生成法提高搜索速度,设计自适应交叉与变异算子使AGA能够在进化速度与解的质量之间进行权衡,并获得全局最优解。结果表明,该算法能跳出局部最优从而获得最优的选址-分配方案,可为应急管理部门和决策机构的应急设施选址规划及应急物资分配提供理论依据和决策参考。     

基于群集动力学模型的密集场所人群疏散问题研究

密集场所人群疏散问题直接关系到大型公共场所的安全保障能力.应用群集动力学理论方法,在密集人群群体流动过程和个体流动过程分析的基础上,对已有的人群疏散数学模型进行改造,使之更加符合实际意义.以实际人群密集场所为例,进行数值仿真,寻求一定人流密度和疏散时间约束下的最佳疏散通道宽度以及关于开放疏散出口数量的最佳疏散策略,以达到最佳的疏散效果.为有效解决应急环境下密集场所人群疏散问题提供了理论依据,可用于指导密集场所建筑物的结构设计改进,以及疏散过程中的调度管理优化等.     

FLAC软件在拦水坝稳定性分析中的应用

坝体作为一个复杂的自然-人工系统,坝体的安全有效性受各种内外因素的影响,管理不当,容易引发各种安全环境问题.评估坝体工作十分重要,对提高坝体的本质安全状况和安全管理水平,减少和控制坝体运行中的危险、有害因素,降低坝体生产安全风险、预防事故发生,保护企业及下游居民的财产安全,保持坝区周边的社会稳定等方面都具有重要的意义.介绍了FLAC的概况,并根据已知的工程地质资料及岩石力学参数,用连续快速拉格朗日分析软件FLAC模拟了拦水坝的稳定性.通过模拟出坝体的应力应变和破坏场,了解坝体可能发生变形破坏的区域.为拦水坝的安全管理提供一些理论方面的依据.根据模拟出来的结果,提出了相应的解决措施,确保其正常运行,不至于发生垮坝事故,避免造成人员伤亡和经济损失.     

Efficacy of handrails in preventing stairway falls: a new experimental approach

In previous studies of stairway handrails, data were derived from static experiments which characterized the influence of the handrail design on ability to generate stabilizing force. This paper describes a novel and safe experimental approach developed to study the biomechanical efficacy of handrail use under dynamic conditions, wherein support-surface motion is used to perturb the balance of the subject who stands on a small (three step), heavily padded mock staircase. A primary objective of this initial study was to determine the influence of factors such as perturbation magnitude, stance leg (left or right), proximity to the handrail, initial hand position (on or off the rail), and ability to complete a step while grabbing the rail. The study was also intended to address a more basic issue: is it even possible to grab a handrail with sufficient speed and accuracy to prevent a fall after losing balance on a stairway? Testing of four healthy young adults demonstrated that sizeable stabilizing handrail force can be generated very quickly (up to 60% of body weight in less than 1 second) in response to loss of balance. Furthermore, these grabbing responses were clearly of functional significance, resulting in a marked reduction in the incidence of ‘falls’ (i.e. landing on the padded surface) compared to trials where the handrail was absent. The most consistent aspect of the force generation was the tendency to exert a forward axial force along the rail. An unexpected finding was that this force often appears to be exerted through a pulling, rather than pushing, action, because of the posterior location of the grip relative to the body. Although most of the force components tended to increase with perturbation magnitude, the lateral forces appeared to be most dependent on whether a step was taken. Stance leg had few effects, but variation in proximity to the rail was found to influence the angle at which the hand approached the rail. Gripping the rail prior to perturbation led to a greater tendency to pull upwards. Implications of these findings for safer handrail design are discussed.     

Ranking and selecting dangerous crash locations: correcting for the number of passengers and Bayesian ranking plots

INTRODUCTION: In this paper a sensitivity analysis is performed to investigate how big the impact would be on the current ranking of crash locations in Flanders (Belgium) when only taking into account the most serious injury per crash instead of all the injured occupants. RESULTS: Results show that this would lead to a different selection of 23.8% of the 800 sites that are currently considered as dangerous. CONCLUSIONS: Considering this impact quantity, the researchers want to sensitize government that giving weight to the severity of the crash can correct for the bias that occurs when the number of occupants of the vehicles are subject to coincidence. Additionally, probability plots are generated to provide policy makers with a scientific instrument with intuitive appeal to select dangerous road locations on a statistically sound basis. Impact on industry Considering the impact quantity of giving weight to the severity of the crash instead of to all the injured occupants of the vehicle on the ranking of crash sites, the authors want to sensitize government to carefully choose the criteria for ranking and selecting crash locations in order to achieve an enduring and successful traffic safety policy. Indeed, giving weight to the severity of the crash can correct for the bias that occurs when the number of occupants of the vehicles are subject to coincidence. However, it is up to the government to decide which priorities should be stressed in the traffic safety policy. Then, the appropriate weighting value combination can be chosen to rank and select the most dangerous crash locations. Additionally, the probability plots proposed in this paper can provide policy makers with a scientific instrument with intuitive appeal to select dangerous road locations on a statistically sound basis. Note that, in practice, one should not only rank the crash locations based on the benefits that can be achieved from tackling these locations. Future research is also needed to incorporate the costs of infrastructure measures and other actions that these crash sites require in order to enhance the safety on these locations. By balancing these costs and benefits against each other, the crash locations can then be ranked according to the order in which they should be prioritized.     

同轴分层流旋流燃烧器NO_x生成特性研究

同轴分层流旋流燃烧器是一种新型低NO_x燃烧器,可以通过1、2次风的适当配置,达到降低NO_x生成的目的.在自行开发设计的同轴旋转分层流旋流燃烧器上,对不同1、2次风旋流强度,1、2次风不同配比工况下NO_x的生成特性进行了研究.结果表明,1次风需要保持一定的旋流强度,并达到一定的水平,同时2次风配以适当的旋流强度,在一定的1次风率下,才能达到降低NO_x生成量的目的.在本文试验条件下,1次风旋流强度为0.35～0.47,同时2次风配以适当的旋流强度和1次风率,分别为1.30～1.50和33%,NO_x生成量低于其他工况.在运用旋转射流分层流原理的同时配以适当的机械方法,如增加扩口,NO_x生成与排放水平可以进一步适当降低.     

An approach for determining the extent of contribution of construction project features to accident causation

In the pursuit of Health and Safety (H&S) improvement within the UK construction industry, several studies have been conducted to identify accident causal factors to enable the development of accident prevention measures. Adding to such studies, a critique of H&S literature demonstrates that construction project features (CPFs) such as the nature of project, method of construction, site restriction, project duration, procurement system, design complexity, level of construction, and subcontracting contribute to accident causation and that their contribution is through the introduction of proximal accident causal factors into the construction process. However, the extent of this contribution by these CPFs remains sparingly known and requires further investigation. The study provides this insight by indicating that the extent to which CPFs contribute to accident causation is influenced by two factors; the extent to which the proximal factors contribute to accident causation; and the extent to which the proximal factors are prevalent within the CPFs. In line with this fresh insight, an approach for determining the extent to which CPFs contribute to accident causation is put forth. The approach proposes to use a qualitative–quantitative rating scale to determine the two determinant factors and then combine them using a mathematical formula to obtain the extent to which CPFs contribute to accident causation. By this approach the grey areas in literature concerning the extent to which CPFs contribute to accident causation will be illuminated and by that contribute to improvement in construction accident prevention.     

海南岛香蕉园土壤肥力现状及变化趋势分析

对海南岛5大香蕉种植区(乐东、东方、昌江、临高、儋州)各大香蕉基地的共计57蕉园土壤样品及与之对应的20个对照样品进行了pH值、有机质、碱解氮、速效磷、速效钾、交换性钙镁、有效硫、有效铜锌及有效硼含量分析.结论如下:1)海南岛各大香蕉基地由于管理水平不同,其土壤肥力水平差异相当明显,以乐东地区蕉园土壤肥力为最低.2)全区蕉园土壤较对照土壤pH值降低(下降0.27～0.91个单位);有机质质量比降低(下降0.009～0.063g/kg);碱解氮质量比降低(下降0.72～22.75 mg/kg);速效磷大量积累(上升17.4%～1552.4%);速效钾质量比增加缓慢(上升161.94～312.18 mg/kg);中量元素交换性钙、速效硫含量有一定幅度的增加(Ca上升0.39～3.94cmol/kg,S上升1.52～43.00mg/kg);交换性镁有下降趋势(下降0.01～0.15 mg/kg);微量元素中速效性铜有增加趋势(上升0.16～1.49mg/kg)而速效锌、速效硼有下降趋势(Zn下降0.10～2.04mg/kg,B下降0.01～0.04mg/kg).