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介绍了如何在国家级生态示范区的可持续发展评估中运用灰色系统理论构建定量评估系统模型,并给出了关系型指标表、量纲模型、多元灰色预测模型和发展系数模型以及应用实例.根据该评估系统模型所开发的灰色评估系统由数学模型、计算机软件和硬件组成,可自动完成量纲统一、指标预测、相关分析、综合评估和趋势图表的运算和输出. 相似文献
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目的 评估在役15万吨级FPSO在某海域百年一遇极端波浪作用下典型横剖面的水动力特性,进而得到FPSO的极值荷载,作为FPSO返坞改造的关键控制参数。方法 基于国产自主三维频域线性势流软件COMPASS-WALCS,建立15万吨级FPSO湿表面网格模型,根据三维绕射-辐射理论,计算湿表面上的水动力荷载,将每个绕射单元上的水动压力直接映射到结构模型上进行计算。采用谱分析方法对百年一遇海况进行分析,得到短期运动极值响应。对响应幅值算子(RAO)和波能谱密度进行谱分析,得到极端波浪下的响应谱,进而得到浮体运动和波浪荷载短期预报各种统计值,利用统计方法求得短期响应的最大值。结果 计算了船中部Fr143横剖面的载荷极值,即垂向弯矩、垂向剪力、剖面型心加速度等,发现船舶迎浪时弯矩值最大,随着浪向角增大,弯矩值逐渐减小,剖面垂向剪力则随着浪向角增大逐渐增大。结论 FPSO在极端波浪作用下,其大迎浪角条件下荷载更加危险,需要给予格外关注。 相似文献
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Lobb B 《Journal of Safety Research》2006,37(4):359-365
INTRODUCTION: Train-pedestrian collisions have been shown to be the leading cause of fatality in train-related accidents worldwide, yet there is remarkably little research in this area. METHOD: In this paper, the major types of railway transportation accident research are briefly highlighted to indicate the general context of research concerning train-pedestrian collisions, which are then reviewed. Themes emerging from the diverse research are identified, the various strategies that have been proposed for prevention of railway pedestrian accidents are discussed, and the empirical evidence for their efficacy examined in the light of the much more extensive literature on road pedestrian accidents. Finally, it is proposed that application of current theory in behavioral and cognitive psychology may usefully inform future research in transportation safety. 相似文献
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INTRODUCTION: Psychological contracts of safety are conceptualized as the beliefs of individuals about reciprocal safety obligations inferred from implicit or explicit promises. Although the literature on psychological contracts is growing, the existence of psychological contracts in relation to safety has not been established. The research sought to identify psychological contracts in the conversations of employees about safety, by demonstrating reciprocity in relation to employer and employee safety obligations. The identified safety obligations were used to develop a measure of psychological contracts of safety. METHOD: The participants were 131 employees attending safety training sessions in retail and manufacturing organizations. Non-participant observation was used to collect the data during safety training sessions. Content analysis was used to analyze the data. Categories for coding were established through identification of language markers that demonstrated contingencies or other implied obligations. RESULTS: Direct evidence of reciprocity between employer safety obligations and employee safety obligations was found in statements from the participants demonstrating psychological contracts. A comprehensive list of perceived employer and employee safety obligations was compiled and developed into a measure of psychological contracts of safety. A small sample of 33 safety personnel was used to validate the safety obligations. CONCLUSIONS AND IMPACT ON INDUSTRY: Implications of these findings for safety and psychological contract research are discussed. 相似文献
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我国煤矿安全生产事故的致灾因素分析 总被引:1,自引:0,他引:1
煤矿安全不仅关系到广大煤矿工人的生命财产安全、煤炭的安全开采,还关系到煤炭企业的和谐稳定.煤矿安全工作是党和政府管理社会、为人民服务的基本任务,是全面落实科学发展观、建设和谐社会的重要组成部分.首先对我国煤矿安全形势进行了分析,随后介绍了事故致因理论的发展,结合我国煤矿事故的特点运用现代事故致因理论对一起煤矿事故进行了分析,最后得出提高煤矿安全监管的措施. 相似文献
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数量化理论Ⅲ及其在煤与瓦斯突出危险性评估中的应用 总被引:1,自引:0,他引:1
研究了数量化理论Ⅲ建立煤与瓦斯突出危险性的原理和方法,以瓦斯地质学理论为基础,建立了包括煤层瓦斯含量、煤层瓦斯压力、煤层分岔合并现象、地质构造复杂程度、煤的破坏类型等11个地质因素的煤层突出危险性评估指标体系。以数量化理论Ⅲ为工具,实例分析得出马依西一井3煤层突出危险性的敏感地质因素及因素轴F1,以该轴上得分大于0.1的地质因素作为强突出的敏感地质因素;得分小于-0.1的地质因素作为弱突出的敏感地质因素,得分在0.1--0.1之间的地质因素作为中等突出的敏感地质因素,将矿井划分为强突出、中等突出和弱突出三个区域。该方法实现了地勘阶段煤与瓦斯突出的定量分析,进一步细化了突出区域的划分。 相似文献
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在现场调研与文献分析的基础上,提出了排土场滑坡灾害预警指标体系。基于物元理论和关联函数,构建了露天矿山排土场滑坡灾害可拓预警模型。采用基于测度改进的层次分析法客观地确定评价指标权重,较好地消除了人为因素带来的偏差;以综合关联度作为评价准则进行滑坡危险性等级判定,进而对排土场滑坡灾害进行预警。利用该模型对某铁矿排土场的滑坡危险性进行预警评价,得到了与实际情况吻合的警情,并针对存在的问题提出了相应的改进措施 相似文献
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Quantifying the squeezing or stretching of fisheries as they adapt to displacement by marine reserves 下载免费PDF全文
The designation of no‐take marine reserves involves social and economic concerns due to the resulting displacement of fishing effort, when fishing rights are removed from those who traditionally fished within an area. Displacement can influence the functioning of the fishery and success of the reserve, yet levels of displacement are seldom quantified after reserve implementation and very rarely before that. We devised a simple analytical framework based on set theory to facilitate reserve placement. Implementation of the framework requires maps of fishing grounds, fishing effort, or catch per unit effort for at least 2 years. The framework quantifies the level of conflict that a reserve designation might cause in the fishing sector due to displacement and the opportunities to offset the conflict through fisher spatial mobility (i.e., ability of fishers to fish elsewhere). We also considered how the outputs of the framework can be used to identify targeted management interventions for each fishery. We applied the method in Honduras, where the largest marine protected area in Central America is being placed, for which spatial data on fishing effort were available for 6 fisheries over 3 years. The proposed closure had a greater negative impact on the shrimp and lobster scuba fisheries, which concentrated respectively 28% and 18% of their effort inside the reserve. These fisheries could not accommodate the displacement within existing fishing grounds. Both would be forced to stretch into new fishing grounds, which are available but are of unknown quality. These stakeholders will likely require compensation to offset costly exploratory fishing or to travel to fishing grounds farther away from port. 相似文献