舰艇舱室性能化防火设计研究

随着舰艇舱室设备自动化程度的提高,目前许多发达国家的舰艇舱室防火设计正逐步从"处方式"规范转换到性能化设计.由于舰艇是可移动的海上建筑物,所以其性能化设计可以充分借鉴建筑性能化防火设计.首先简述了建筑性能化防火设计的概念和设计方法;然后结合舰艇舱室和建筑舱室结构和消防能力的异同点,提出了舰艇舱室性能化防火设计的实施步骤,并给出了某舰艇舱室性能化防火设计的算例.在某舱室性能化防火设计的工程算例中,首先采用火灾安全工程分析舰艇舱室性能化防火设计的总体设计要求和性能判据;然后对确定性指标进行计算;最后分析确定性指标是否符合防火设计总体要求.结果说明性能化防火设计对"处方式"防火设计的某些定性指标进行了量化补充,而且为舰艇舱室防火设计提供了必要的理论支持.     

Minimum-loss design of x-bar charts for correlated data

When the x-bar chart is used to monitor a production process, three parameters should be determined: the sample size, the sampling interval between successive samples, and the control limits for the chart. In 1956, Duncan presented a cost model to determine the three parameters, which is called the economic design of x-bar charts. In 1995, Alexander et al. combined Duncan’s cost model with the Taguchi’s quality loss function to present a loss model for determining the three parameters. When designing an x-bar chart, one usually assumes that the measurements within a sample are independent; however, this assumption may not be true for some processes. In this paper, we develop the minimum-loss design of x-bar charts for correlated measurements within a sample by incorporating the Taguchi’s quality loss function. An example of orange juice production process is presented to illustrate the solution procedure. From the results of sensitivity analysis, we find that as the measurements in the sample are positively correlated, highly correlated data result in a smaller sample size and a frequent sampling interval; however, as the measurements in the sample are negatively correlated, highly correlated data yield a smaller sample size and a narrower control limits.     

泡沫铝填充结构救生舱多目标优化设计

为提高救生舱的安全性,设计了1种泡沫铝填充结构救生舱。利用Workbench对原型救生舱进行静力分析,以泡沫铝填充结构救生舱的内外板厚、泡沫铝厚、纵向和横向加强筋宽为设计变量,以原型救生舱的最大应力、最大位移以及模型质量为约束条件,以泡沫铝填充结构救生舱的静态最大应力、最大位移及质量为目标函数,分析各设计变量对目标函数的灵敏度并进行多目标优化设计;并利用数值仿真方法研究优化后的泡沫铝填充结构救生舱的抗爆炸冲击性能。结果表明:与传统救生舱相比,优化后的泡沫铝填充结构救生舱可以显著提高救生舱的静力及抗爆炸冲击能力,进而提高其安全性能。     

建筑施工起重机械事故一线作业人员不安全动作规律研究

为有效预防建筑施工起重机械事故,笔者将建筑起重机械一线作业人员按工种分为设备驾驶员、现场施工人员、安拆维修工和信号司索工4种。以行为安全“2-4”模型作为分析工具,对70起建筑施工起重机械事故样本中各类人员不安全动作进行分析。结果表明:建筑施工起重机械事故一线作业人员发出不安全动作196次,其中设备驾驶员发出不安全动作29次,占比41.43%,安拆维修工、信号司索工、现场施工人员分别发出不安全动作18、14和9次,占比分别为25.71%、20%和12.86%。一线作业人员常见的不安全动作是擅自拆除或起吊、未佩戴劳动防护用品、作业现场环境误判断、违反安全操作规程、资质不足作业,其中资质不足作业、违反安全操作规程和作业现场环境误判断发生频次最高。     

Comparison of Two Methods for Judging Distances Near Overhead Power Lines

Sixteen certified crane operators performed several series of boom movements toward a segment of a typical power line using a 100-ton lifting capacity crane equipped with an 18-m boom, a single lifting cable, and a hard ball hook. The operators were instructed to stop the crane movement when the lifting cable reached the edge of the danger zone located 3 m from the power line. To achieve each maneuver, they evaluated the distance between the nearest wire and their crane using two methods: free sighting and the use of highly visible markers delineating the edge of the danger zone. The dependent measure was the distance between the lifting cable and the edge of the danger zone. Results showed that operators were generally unreliable when judging the distance between their crane and the power line when sighting the power line directly, but the use of markers proved to be much more precise and reliable in targeting the edge of the danger zone.     

桥式起重机安全评估指标体系研究和系统设计

在对桥式起重机的设计、结构组成和常见事故故障资料进行调查研究的基础上,分析了桥式起重机在工程应用中遇到的不安全因素,建立了较完善的安全评估指标体系。设计了一种基于模糊神经网络的桥式起重机安全评估系统并对系统的软件功能设计进行了初步探讨。建立了模糊神经网络评估数学模型,利用MATLAB工具对模型进行了仿真验证,结果表明此模型是可行的。通过研究,为进一步针对桥式起重机展开定性、定量评估及安全管理与决策提供了有益参考     

基于人工神经网络模型的舰船防火设计方法

根据舰船实际和火灾理论,建立了舰船舱室火灾危险性的动静二类4个指标:失火危险性指标、舱室相关度指标、设备使用状态指标和人员状态指标,对舰船各种舱室的火灾危险性进行量化。笔者先给出规范中9类舱室的各指标值,应用笔者所开发的神经网络模型,建立舱室火灾危险性指标值与舱室分隔等级的关系模型,求出舱室防火分隔等级值,降低了对设计者经验的要求。运用开发的模型对某大型舱室进行防火设计,获得的结果与其他方法的结果基本一致,可供舰船防火设计时参考。     

防火型家用救生舱舱体热环境与结构优化研究

为优化防火型家用救生舱舱体隔热设计,提出了适用于火灾工况的多重绝热结构设计方法,采用数值模拟和实验的方法研究了防火型家用救生舱舱体的温度分布,分析了12种不同围护结构形式下舱体的绝热保温性能,获得多重绝热结构的最优厚度及绝热材料的最优配比。研究成果可为防火型家用救生舱的隔热设计提供一定的理论支撑和工程设计参考。     

Anthropometry for Design for the Elderly

This paper presents anthropometric data on elderly people in Australia. Data were collected in the metropolitan city of Sydney, NSW, Australia. In all 171 elderly people (males and females, aged 65 years and above) took part in the study. Mean values, standard deviations, medians, range, and coefficients of variation for the various body dimensions were estimated. Correlation coefficients were also calculated to determine the relationship between different body dimensions for the elderly population. The mean stature of elderly Australian males and females were compared with populations from other countries. The paper discusses design implications for elderly people and provides several examples of application of the anthropometric data.     

基于区间分析的履带起重机结构非概率可靠性研究

臂架结构作为履带起重机的重要部件,其结构的强度、刚度和稳定性决定了整个起重机的安全性和使用性能。为了预测履带起重机臂架结构的可靠度,采用区间非概率研究履带起重机的可靠性,只需知道不确定参量的界限而不需知道其分布情况,就能求出各功能函数的可靠性指标;将履带起重机臂架的额定起重量、起升载荷偏摆角度、起升冲击系数等不确定参量看成区间变量,建立了以臂架强度、刚度、整体稳定性为失效模式的可靠性分析模型;将区间变量标准化,在标准化区间变量的扩展空间中,按无穷范数度量从坐标原点到失效面的最短距离,以此来判断结构的非概率可靠度。最后,用该模型对现有某型号履带起重机臂架进行了可靠性分析,结果表明,用该方法得到的履带起重机区间非概率可靠度η1,符合实际情况。     

起重机械疲劳寿命分析预测软件开发及工程应用

随着国民经济的快速发展,起重机械的应用越来越广泛。在役起重机械的疲劳及由此引起的安全问题也愈来愈突出。以名义应力法为疲劳寿命预测的基本方法,采用双参数雨流计数法对随机载荷进行处理,根据Miner线性累积损伤模型计算随机载荷引起的疲劳累积损伤,然后对疲劳寿命做出分析预测。基于Matlab软件的图形用户接口开发环境,设计了工程应用型的疲劳寿命分析预测软件。采用所开发的疲劳寿命分析预测软件对起重机热点区的累积损伤和疲劳寿命进行分析计算与预测。根据4个测点的疲劳寿命分析结果,说明本文采用起重机结构疲劳损伤寿命预测方法比较合理,开发的疲劳寿命分析预测软件具有较好的工程应用价值,为快速进行在役起重机的疲劳寿命评估提供了平台。     

塔机起重作业夜间照明工效的BIM辅助优化研究*

为提升塔式起重机施工作业的夜间照明工效水平,采用数学模型和BIM技术相结合的方法,以灯源的光通量及入射角为光学驱动参数,模拟眩光值、照度及其均匀度等光学变量,建立照明工效的光度学BIM辅助优化模型,优化起重作业照明灯源光学参数。研究结果表明:对塔式起重机施工作业区照明灯源光学参数进行组合优化后,夜间起重作业面照度及其均匀度显著提升,眩光值满足起重作业视觉环境条件。研究结果可为塔式起重机夜间起重作业照明方案设计提供科学依据。     

建筑大空间火灾模拟及升温计算简单公式

钢结构经常用于建筑大空间环境。因为使用和功能要求,建筑大空间内通常无法设置防火墙来阻止火灾的水平传播,而是通过设置燃烧岛、防火舱及防火隔离带等措施将可燃物限制在一定区域内。大空间内可能的火灾为区域火灾。给出了模拟大空间火灾的理论模型和升温计算简单公式。公式基于火羽流相关理论,并引入工程相关常数得到。通过工况分析,考察了两种不同火灾场景,公式的计算结果与场模拟软件FDS结果进行了比较,二者符合良好。所给出的公式形式简单,式中参数的物理意义明确,推荐用于实际工程计算。     

塔式起重机安全性研究与展望

塔式起重机作为建筑施工的重要象征与主要运输机械，在建筑业得到了广泛应用；它的工作特点是，根据建筑需要将物品在很大空间内升降和搬运，属危险作业，因此，如果在塔式起重机的设计，制造、安装、使用和维修等环节上略有疏忽，就可能造成人员伤亡和设备事故，在实际工作中，如何提高塔式起重机的本质安全，如何合理地使用和管理好塔式起重机，让塔式起重机更好地发挥作用，是建筑业亟待解决的难题之一，本简述了塔式起重机的发展历史，分析了塔式起重机的安全现状，提出了塔式起重机安全问题的对策，展望了塔式起重机安全性技术的发展趋势。     

Anthropometric study of emergency medical services providers (EMSP) in the United States

Introduction: Design of next-generation ambulance patient compartment requires up-to date anthropometric data of emergency medical service providers (EMSP). Currently, no such data exist in the U.S. A large-scale anthropometric study of EMSP in the U.S. were conducted. This report provided the summary statistics (means, standard deviation, and percentiles) of the study’s results and examined the anthropometric differences between the EMSP dataset and the U.S. general population, and between the EMSP dataset and U.S. military personnel dataset, respectively. Method: An anthropometric study of 471 male and 161 female EMSP from across the continental US was conducted, using a sampling strategy that took into account age, sex, and race strata. Results: On average, male EMSP were found to be 18 mm taller and 7 kg heavier than US male general population, and 19 mm taller and 11 kg heavier than US male military personnel. Female EMSP were found to be 25 mm taller than US female general population, and 10 kg heavier than US female military personnel. Conclusions: These results showed that it would be inappropriate to apply general population or military data to the design of next-generation ambulance patient compartment. This new dataset provided the most recent and accurate EMSP anthropometric measurements available in the US. Practical Application: Data from this study provided an invaluable resource for the design of next-generation ambulances in the US.     

基于物联网的起重机智能作业管理系统设计与实现

采用物联网技术,设计一种由主控机PC、无线射频模块和读卡器模块等部分组成的起重机作业管理系统,实现人机互认及作业记录管理。详细介绍了系统硬件结构设计原理及实现方法,给出了作业管理系统软件设计。实际调试表明：该系统能够实现对作业人员身份的识别和起重机作业记录管理等功能,且具有数据传输有效距离远、移动性强、安装简单和扩展性好等特点。     

Hand anthropometric study in northern Colombia

The main purpose of this study is to gather information about the dimensions of the northern Colombian (Caribbean region) population, focusing on the dimensions of the hand and comparing them with measurements from other regions. Thirty-two hand dimensions were chosen and 120 males and 86 females were measured. Results indicated that there were differences between the dimensions of the hand for men and women, showing that men are larger. Also, there was a comparison made between some measurements of other studies in different regions of Colombia, the USA, Chile, Jordan, Korea and Japan. The results indicated important physiological differences between regions in Colombia and across countries. It was therefore concluded that differences in anthropometric measurements must be included in the design and procurement of machinery and apparatus in order to avoid productivity loss, occupational injuries or illness.     

基于减振降噪分析的高效堆垛机设计

物流业的快速发展,使得堆垛机趋向结构大型化和运行高速化。而随之出现的是振动过大及噪声污染问题,既影响产品的动态性能,又存在着安全隐患。为解决上述问题,从堆垛机的结构入手,重点分析振动和噪声产生的主要原因,运用SolidW orks(三维绘图)及其插件Cosmos/W orks(有限元分析)、Cosmos/Motion(动态仿真)软件,通过对不同结构参数和不同结构形式的(超高速/大高度)高效率堆垛机的三维建模、动态仿真与有限元分析,评价其模态和频率指标,摒弃原设计的等截面形式而采用效果最佳的变截面结构形式。结果表明,改进的设计满足设计规范要求,并进一步总结和分析应当重视的问题,对解决高效率堆垛机振动过大和噪音污染问题具有现实的指导意义。     

起重机主梁裂纹修补参数的研究

采用ANSYS有限元分析软件，对因出现裂纹的起重机主梁而添加的补强板进行系列计算，得出修补后主梁裂纹的应力及应力强度因子的变化规律，结果表明，只有采用适当参数的补强板，才可消除起重机主梁裂纹的扩展趋势，从而保证起重机的安全。