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1.
Practitioners are continuing to develop egress modelling software for the design of the built environment. These models require data about human behaviour and factors for calibration, validation and verification. This study aims to address the specific data and knowledge gap: emergency egress of the elderly. Such data are difficult to collect given privacy and consent concerns, with strong relationships generally being required between residences and researchers. Through the observation of nine fire drills at six Canadian long-term care (LTC) and retirement homes, specific evacuation actions and behaviour were observed for 37 staff members and information about the evacuation of 56 residents was collected. These drills demonstrated that emergency egress in LTC and retirement homes is highly staff dependent with 72% of residents recorded requiring full assistance at all stages of movement in evacuation, and that the type of announced/unannounced drill and level of resident care will affect the type of data collected. The development of travel speed and pre-movement is discussed subject to limitation with qualitative behavioural insights of residents that were observed. This study provides valuable methodological discussion on how to conduct behavioural studies in similar highly restricted research environments. Specific attention is given to understanding the considerations that must be made when using fire drills as data sources, and the impact that these can have on using such data for modelling. This study may inform the initial setup and programming of evacuation models from an actions and behavioural perspectives of staff members and residents.  相似文献   
2.
To quantify the evacuation process, evacuation practitioners use engineering egress data describing the occupant movement characteristics. These data are typically based to young and fit populations. However, the movement abilities of occupants who might be involved in evacuations are becoming more variable—with the building populations of today typically including increasing numbers of individuals: with impairments or who are otherwise elderly or generally less mobile. Thus, there will be an increasing proportion of building occupants with reduced ability to egress. For safe evacuation, there is therefore a need to provide valid engineering egress data considering pedestrians with disabilities. Gwynne and Boyce recently compiled a series of data sets related to the evacuation process to support practitioner activities in the chapter Engineering Data in the SFPE Handbook of Fire Protection Engineering. This paper supplements these data sets by providing information on and presenting data obtained from additional research related to the premovement and horizontal movement of participants with physical‐, cognitive‐, or age‐related disabilities. The aim is to provide an overview of currently available data sets related to, and key factors affecting the egress performance of, mixed ability populations which could be used to guide fire safety engineering decisions in the context of building design.  相似文献   
3.
Lévy flights have gained prominence for analysis of animal movement. In a Lévy flight, step-lengths are drawn from a heavy-tailed distribution such as a power law (PL), and a large number of empirical demonstrations have been published. Others, however, have suggested that animal movement is ill fit by PL distributions or contend a state-switching process better explains apparent Lévy flight movement patterns. We used a mix of direct behavioural observations and GPS tracking to understand step-length patterns in females of two related butterflies. We initially found movement in one species (Euphydryas editha taylori) was best fit by a bounded PL, evidence of a Lévy flight, while the other (Euphydryas phaeton) was best fit by an exponential distribution. Subsequent analyses introduced additional candidate models and used behavioural observations to sort steps based on intraspecific interactions (interactions were rare in E. phaeton but common in E. e. taylori). These analyses showed a mixed-exponential is favoured over the bounded PL for E. e. taylori and that when step-lengths were sorted into states based on the influence of harassing conspecific males, both states were best fit by simple exponential distributions. The direct behavioural observations allowed us to infer the underlying behavioural mechanism is a state-switching process driven by intraspecific interactions rather than a Lévy flight.  相似文献   
4.
The smoke suppression of rigid polyurethane foam (RPUF) modified by melamine was investigated based on three sections: the condensed phase, the carbon layer, and the gas phase. In the condensed phase, the results of thermogravimetry, X‐ray photoelectron spectroscopy (XPS) N1S spectrum, and Fourier transform infrared spectroscopy indicated that melamine could suppress the degradation of RPUF by reacting with the aromatic hydrocarbons. It also reduced the smoke generation because the volatilizable aromatic hydrocarbons were the principal smoke precursors in a fire. In the carbon layer, the decrease from 38.50% to 24.76% of the inner layer oxygen content identified by XPS full‐spectrum and C1S spectrum indicated that melamine could prevent oxygen from transferring into the inner foam by the formation of an enhanced surface carbon layer, and the enhanced carbon layer could also block the release of smoke precursors. In the gas phase, the content of total aromatic hydrocarbons declined to 59.12% according to pyrolysis gaseous chromatography mass spectroscopy and indicated that melamine could reduce the smoke precursors. The results of smoke density chamber and cone calorimeter tests revealed that the addition of the melamine could decrease the smoke density of burning RPUF. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
5.
摩擦换向抽油机采用开关磁阻电动机或变频调速电动机,其特点是可以频繁双向旋转,带动摩擦轮正反转,实现光杆的上行下行。该抽油机运动特点与游梁式抽油机运动特点有较大区别,文章分析了摩擦换向抽油机的运动特点,给出了该机悬点位移、速度、加速度的计算方法。  相似文献   
6.
柳正钧  陈春丽 《核动力工程》1993,14(1):83-87,96
本文叙述了反应堆保护系统停棒与汽轮机降功率子系统的系统功能、保护参数和秦山核电站控制棒组插入监测器的设计与参数选择,确定了控制棒提升上极限值和在不同工况下棒插入低位、低-低位整定值,并在热态零功率条件下加以验证。试验证明参数选择是合理的,为功率运行阶段提供了数据。  相似文献   
7.
苏北-南黄海盆地构造演化   总被引:13,自引:1,他引:12       下载免费PDF全文
杨琦  陈红宇 《石油实验地质》2003,25(Z1):562-565
苏北及南黄海盆地是由多期、多类盆地叠加的复合残留盆地,地质概况基本相似,成因演化近同,自元古界下扬子板块形成后,主要经历了古-中生代地台、中生代前陆盆地、走滑拉分盆地时期以及新生代断陷、坳陷盆地时期.在古生代-中生代发展过程中是一个整体,晚白垩世盆地演化出现分化,发育伸展盆地群,形成一系列叠置在中、古生代盆地之上的箕状断陷,箕状断陷的发育及分布明显受中-古生界内部先存逆冲断裂的控制.  相似文献   
8.
剪切机的运动学分析   总被引:1,自引:0,他引:1  
剪切机是工业生产中常用的设备,广泛应用于剪切各种材料。某厂使用的小型剪切机因生产需要将其改装成自动剪切设备,但理论上难以确定其最小剪切性能。笔者采用图解法对其进行运动和受力分析,得出在调速电机转速一定的情况下能够剪切的钢材直径,对生产使用具有较高的理论指导价值。  相似文献   
9.
电梯门机控制系统的运行曲线设计   总被引:1,自引:0,他引:1  
为了实现电梯轿厢门的开门和关门快速且平稳地运行,介绍了一种基于高性能微型机的门机控制系统结构和门位移的检测原理,以门位移量作为控制系统的反馈量,对门机运行速度进行了分区设计。在高速附近的变化区,门机速度匀速变化时,进行了门机开门和关门控制曲线的计算,推导出运行位移与门机速度具有二次曲线的关系,进而对微型机控制的软件流程进行了设计,达到了门机高低速运行的平稳过渡。最后,给出了实际运行系统的主电路电压波形。  相似文献   
10.
Deciding between the different policy approaches available for reducing human exposures to indoor pollutants is an exceptionally complex task. These options can range from waiting until more definitive information is available to enacting regulatory standards, with many variations in between. This paper presents some of the factors policy-makers must consider in establishing indoor air quality policies, and the role researchers should play in ensuring that indoor air policies are based on the best available scientific information.  相似文献   
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