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411.
This paper attempts to replicate a safety climate model originally tested in Australia to assess its applicability in a different context: namely, across production workers in 22 medium-sized metal processing organizations in Austria. The model postulates that safety knowledge and safety motivation mediate the relation between safety climate on the one hand and safety compliance and participation on the other. Self-report data from 1075 employees were analyzed using structural equation modeling (SEM). The results of the replication study largely confirmed the original safety climate model. However, in addition to indirect effects, direct links between safety climate and actual safety behavior were found.  相似文献   
412.
The finite difference time domain method (FDTD) is frequently used for the numerical solution of a wide variety of electromagnetic (EM) problems and, among them, those concerning human exposure to EM fields. In many practical cases related to the assessment of occupational EM exposure, large simulation domains are modeled and high space resolution adopted, so that strong memory and central processing unit power requirements have to be satisfied. To better afford the computational effort, the use of parallel computing is a winning approach; alternatively, subgridding techniques are often implemented. However, the simultaneous use of subgridding schemes and parallel algorithms is very new. In this paper, an easy-to-implement and highly-efficient parallel graded-mesh (GM) FDTD scheme is proposed and applied to human–antenna interaction problems, demonstrating its appropriateness in dealing with complex occupational tasks and showing its capability to guarantee the advantages of a traditional subgridding technique without affecting the parallel FDTD performance.  相似文献   
413.
Cold protective clothing was studied in 2 European Union projects. The objectives were (a) to examine different insulation calculation methods as measured on a manikin (serial or parallel), for the prediction of cold stress (IREQ); (b) to consider the effects of cold protective clothing on metabolic rate; (c) to evaluate the movement and wind correction of clothing insulation values.

Tests were carried out on 8 subjects. The results showed the possibility of incorporating the effect of increases in metabolic rate values due to thick cold protective clothing into the IREQ model. Using the higher thermal insulation value from the serial method in the IREQ prediction, would lead to unacceptable cooling of the users. Thus, only the parallel insulation calculation method in EN 342:2004 should be used. The wind and motion correction equation (No. 2) gave realistic values for total resultant insulation; dynamic testing according to EN 342:2004 may be omitted.  相似文献   
414.
PROBLEM: Continuous progress in the occupational safety and health field, as well as social-economic development, generates a need for access to definitions. Definitions are usually scattered in many sources and not easy to find. Electronic documents give new opportunity to information access. METHOD: As an experiment, the feasibility of automatic full-text searching of definitions was examined using the Encyclopaedia of Occupational Health and Safety, edited by the International Labour Organization (ILO), on CD-ROM. DISCUSSION: The results were compared with the traditional index search by subject, using the paper version of the encyclopedia. The automatic search appeared successful; about 100 definitions were excerpted the automatic way. IMPACT ON INDUSTRY: As in most industries, finding accurate information is a necessity in the safety industry. The electronic document seems to be a powerful instrument as a source of definitions and can be quite easy to use by specialists as well as safety personnel in information processing.  相似文献   
415.
Dispersion models require as input various geometrical parameters to calculate the flow field and dispersion characteristics in the urban environment. As a result of recent advances in digital photogrammetry and remote sensing, databases of the actual 3-D geometry of city centre areas are now increasingly available. In this work we outline a procedure to reduce this large amount of data to a structured input for urban pollution dispersion models, i.e. to extract the important flow and dispersion parameters from the urban databases. Based on a review of the scientific literature, we have identified a number of parameters relevant to the modelling of pollution dispersion and atmospheric flows in urban areas. These parameters are: the plan and frontal area densities, the plan and frontal area density as a function of height, the distribution of heights, their standard deviation, the aerodynamic roughness length and the sky view factor.These parameters are obtained by analysing urban Digital Elevation Models (DEMs) which are regularly spaced grids of elevation values. Examples of the parameters calculated from high-resolution databases (with pixel size of about 1 m) for three European (London, Toulouse and Berlin) and two North American (Salt Lake City and Los Angeles) cities are presented and discussed. The calculated aerodynamic roughness length was smaller for the European cities than for the North American ones. A multiplicative correction factor to the aerodynamic roughness length is proposed to include the effect of the variability of the building heights.  相似文献   
416.
实际应用的饮食业油烟净化设备(以下简称油烟净化设备)中,以静电式、机械过滤式、湿式,以及由上述三种技术组成的复合式产品为主。荷电湿式油烟净化器的开发应用,将具有很强的市场竞争力,未来几年,静电式技术将继续被广泛采用,机械式技术将更多地作为预处理手段与其他技术组合使用,湿法技术因兼有部分除味和去除柴油灶燃烧颗粒的功能等特点将更有针对性地应用于适当的场所。优化组合而成的经济高效的复合式技术在未来市场中将占据主导地位。  相似文献   
417.
锯屑处理含铬废水的实验研究   总被引:14,自引:0,他引:14  
本文提出一种利用木材加工剩余物——锯屑,处理含六价铬离子废水的方法.实验表明,锯屑对废水中的六价铬离子有一定的去除作用,得到了锯屑吸附水中六价铬离子的吸附等温线,测定了吸附速度,并对pH值、锯屑用量和六价铬离子初始浓度等因素对吸附过程的影响进行了实验研究.  相似文献   
418.
采用缓和湿式氧化工艺处理乙烯废碱液和炼油废碱渣   总被引:3,自引:0,他引:3  
介绍了缓和湿式氧化法处理乙烯废碱液和炼油废碱渣的工艺原理和流程。由试验结果可以看出,利用此工艺处理乙烯废碱液和炼油废碱渣时,反应温度、停留时间不同,S2-去除率和反应产物也不同。在反应温度为120 ℃时,S2-的氧化产物以S2O32-的形式存在;当反应温度升高到150 ℃后,S2-的氧化产物以S2O32-和SO42-的形式并存;在反应温度达到180 ℃后,生成的S2O32-基本上完全转化为SO42-离子。在适宜的工艺条件(反应温度120 ℃,停留时间不低于40 min)下,混合废碱液或乙烯废碱液中S2-的排放浓度可降至2 mg/L以下。  相似文献   
419.
根据高分辨率遥感影像震害房屋的基本特征,提出在该影像条件下,震害房屋信息的自动获取技术应发展以区域分析为基础的识别算法,并给出了适于震害房屋信息获取的区域分析算法的基本概念、框架及实现过程.在此基础上,介绍了一种典型的区域分析框架下的震害房屋自动识别算法,并与点特征判据算法进行了对比.结果表明,基于图像区域分析算法的识别具有很高的精度和易于实现的客观条件.最后指出,在高分辨率卫星遥感影像将成为今后震害信息获取主要数据源的情况下,开发区域分析框架下的震害房屋信息识别算法是未来的发展方向.  相似文献   
420.
着重叙述了测震单台数字化分析软件SSDP、NNVSIAS的系统设置及使用技巧 ,并就工作中出现的一些问题给出具体的解决办法 ,特别对NNVSIAS在震相分析中的正确使用、震源对话框的恰当运用给出了详细的说明。  相似文献   
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