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131.
航空维修差错模式及差错成因的灰色关联分析 总被引:3,自引:2,他引:1
提出一种基于HFACS-ME框架和灰色关联分析法的航空维修差错模式和差错成因之间关系的分析方法。利用该方法分别从"模式—成因"和"成因—模式"2个方向,以"技能差错"和"身体状态差"为例,对差错模式和差错成因之间的关系进行分析,得到影响"技能差错"的主要差错成因依次为空间狭窄、培训不足、工具损坏、身体状态差、精神状态差、空间阻碍,以及"身体状态差"主要影响的差错模式为记忆差错、决策差错、技能差错。结果表明,灰色关联分析法对航空维修差错模式和差错成因之间关系的分析是有效的、可行的。 相似文献
132.
欧日中实施GHS政策的对比和思考 总被引:2,自引:0,他引:2
通过研究欧盟、日本和我国实施全球化学品统一分类和标签制度(GHS)的基本情况,并从实施GHS的框架体系、实施GHS的时间节点、GHS的危险类别和GHS危险类别的判定,4个方面对欧盟、日本和我国实施GHS的现状进行重点研究。通过对比分析得出我国当前实施GHS主要存在4个方面的问题,即缺乏实施GHS的综合法律、实施GHS缓冲期的设置存在问题、缺乏开展GHS分类的配套指南、没有合理的运用"积木原则"。结合我国的实际情况提出3个方面的建议:适时推动我国GHS法律法规体系的建设、在各部门的协作下编制我国的GHS分类指南、合理的运用"积木原则"。通过分析表明:欧盟实施的GHS政策最为完善且力度最强,日本次之;由于充分利用"积木原则",欧盟的GHS类别与日中存在一定的差异;欧日中在数据运用和GHS危险判定原则上存在差异。 相似文献
133.
对Fisher法确定稳定分类数作了一些改进,提出利用β值指标来衡量分类的稳定程度,进而确定合理的分类个数。在实际应用中,证明了该方法是可行的。 相似文献
134.
为提高危险化学品安全管理水平,收集我国134起以人为主因的危险化学品事故,构建危险化学品事故的HFACS-BN模型,并基于贝叶斯网络对危险化学品事故中的人因路径及各因素灵敏度进行分析。研究结果表明:行为违规是导致事故的最主要不安全行为;在复杂路径中,环境因素和操作者状态具有较高的灵敏度,与其相关的风险认知与处理不当是阻碍事故预防的关键因素;在非复杂路径中,操作者状态与运行计划不当具有较高的灵敏度,其所涉及的监督违规、组织过程和组织氛围,是导致危险化学品事故的根本起点,并可依此分析事故直接原因和间接原因;操作者状态在2种路径中均表现出高灵敏度,因此化工企业在人员管理上要加强关注职工状态,减少不安全行为的出现。 相似文献
135.
Theresa Stevens Savery George H. Belt Dale A. Higgins 《Journal of the American Water Resources Association》2001,37(3):641-654
ABSTRACT: Data collected from 121 stream reaches during 1991 to 1993 were evaluated to determine the applicability of the Rosgen Stream Classification System (RSCS) to the low relief terrain within the Chequamegon‐Nicolet National Forest (CNNF) in Wisconsin, USA. All reaches were classified to RSCS Level I and II except that 10.7 percent had sinuosities below the continuum limits and one reach had a predominantly organic substrate. Five of eight possible RSCS Level I types were observed including B, C, D, A, E, and F; 86 percent were C and E types. Seventeen of 94 possible RSCS Level II types were observed. Most reaches were slightly entrenched, had low to moderate width/depth ratios, relatively low sinuosity, low slope, and sand or gravel as the dominant channel material. Discriminant analyses were used to verify the applicability of RSCS for streams within the CNNF; discriminant functions correctly classified 92.5 and 94.7 percent of the Level I and II RSCS types, respectively. When limits for E and F types were modified slightly at Level II by adding an additional category for slopes less than 0.1 percent (a modification we recommend for low relief terrain), discriminant functions correctly classified 99.1 percent of the types. Adding another slope break at 0.3 percent produced similar results. Based on our analyses, RSCS works well within the CNNF and is probably applicable to other areas with low‐relief terrain. 相似文献
136.
137.
Tracy K Kuczenski Donald R. Field Paul R. Voss Volker C. Radeloff Alice E. Hagen 《Journal of the American Water Resources Association》2000,36(1):215-228
ABSTRACT: Recurrent calls for integrated resource management urge that an understanding of human activities and populations be incorporated into natural resource research, management, and protection efforts. In this paper, we hypothesize that watersheds can be a valuable geography for organizing an inquiry into the relationship between humans and the environment, and we present a framework for conducting such efforts. The framework is grounded in the emerging field of landscape ecology and incorporates demographic theory and data. Demography has been advanced by technological capabilities associated with the 1990 Census. Employing Geographic Information System (GIS) tools, we couple Landsat Thematic Mapper (TM) land cover data with census‐derived housing density data to demonstrate the operation of our framework and its utility for better understanding human‐landscape interactions. In our investigation of the Kickapoo Watershed and two sub‐ watersheds, located in southwestern Wisconsin, we identify relationships between landscape composition and the distribution and social structure of human populations. Our findings offer insight into the interplay between people and biophysical systems. 相似文献
138.
GHS化学品危险性分类及其公示要素(上) 总被引:2,自引:0,他引:2
概述了全球化学品统一分类和标签制度(GHS)的产生背景、推行GHS的重要意义,介绍了GHS关于化学品危险性分类和公示要素的主要内容,评估了我国现行化学品危险性分类与GHS分类的差异点,并对我国全面实施GHS提出了若干对策建议。 相似文献
139.
140.
Wendy A. Williams Mark E. Jensen J. Chris Winne Roland L. Redmond 《Environmental monitoring and assessment》2000,64(1):105-114
Accurate delineation and characterization of valley-bottom settings is crucial to the assessment of the biological and geomorphological components of riverine systems; yet, to date, most valley-bottom mapping endeavors have been done manually. To improve this situation, we developed automated techniques in a Geographic Information System (GIS) for delineating and characterizing valley-bottom settings in river basins ranging in size from approximately 1,000–10,000 km2. All procedures were developed with ARC/INFO GIS software and fully automated in Arc Macro Language (AML). The GRID module is required for valley-bottom delineation and slope calculations; whereas characterization (i.e., measuring the width of the valley-bottom zone) requires Coordinate Geometry (COGO) in the ARCEDIT module. The process requires three inputs: a polygon coverage of the analysis area; an arc coverage of its hydrography, and a grid representing its digital elevation. The AML is designed to operate within a wide range of computer memory/disk space options, and it allows users to customize several procedures to match the scale and complexity of a given analysis area with available computer hardware. 相似文献