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131.
灰色聚类——模糊综合评价在空气质量分析中的应用 总被引:1,自引:0,他引:1
根据营口市2005年4个自动监测点位的监测数据,应用灰色系统理论,建立了环境空气质量聚类指标体系,确定了不同环境灰类的灰数,给出了不同灰类的白化函数,标定了灰色聚类权重,并计算出了灰色聚类系数及模糊综合评价级数。针对各监测点位进行了灰色聚类分析,又对全市环境空气质量进行了模糊综合评价,确定了营口市环境空气质量状况。 相似文献
132.
从环保政策出发,依据有关基础资料,结合区域发展规划,以模型计算为基础,现状评价,容量分析和方案优选相结合,确立了环境空气质量功能划分的基本技术方法,具有较强的科学性和系统性。 相似文献
133.
A fuzzy logic model is developed to estimate pseudo steady state chlorophyll-a concentrations in a very large and deep dam reservoir, namely Keban Dam Reservoir, which is also highly spatial and temporal variable. The estimation power of the developed fuzzy logic model was tested by comparing its performance with that from the classical multiple regression model. The data include chlorophyll-a concentrations in Keban lake as a response variable, as well as several water quality variables such as PO4 phosphorus, NO3 nitrogen, alkalinity, suspended solids concentration, pH, water temperature, electrical conductivity, dissolved oxygen concentration and Secchi depth as independent environmental variables. Because of the complex nature of the studied water body, as well as non-significant functional relationships among the water quality variables to the chlorophyll-a concentration, an initial analysis is conducted to select the most important variables that can be used in estimating the chlorophyll-a concentrations within the studied water body. Following the outcomes from this initial analysis, the fuzzy logic model is developed to estimate the chlorophyll-a concentrations and the advantages of this new model is demonstrated in model fitting over the traditional multiple regression method. 相似文献
134.
国外沙漠化监测评价指标与分级标准 总被引:6,自引:0,他引:6
利用国内外有关资料,从狭义沙漠化定义出发,介绍了联合国沙漠化监测评价指标体系、分级标准和评价方法。 相似文献
135.
为了探究公路施工安全事故诱因及其影响关系,基于"4M"理论和事故致因"2-4"模型,识别公路工程施工安全事故致因因素并确定模型框架,运用SPSS Modeler软件对2007~2017年426起事故进行关联规则挖掘,采取路径分析与重要度分析,构建出公路工程施工安全事故致因模型。结果表明:施工单位内外部原因共同引发公路工程施工安全事故,外部原因来源于建设单位、监理单位和勘察设计单位的安全管理缺失,而施工单位内部影响因素中,人的不安全动作、物的不安全因素、不良的生产环境和自然环境是事故发生的直接原因,无效的安全监管和作业层安全素质及能力不强是间接原因,根本原因是施工程序和技术方案存在缺陷,根源原因是决策层和管理层的安全素质及能力有待提高。该模型系统展现了工程施工项目安全事故致因因素的影响关系和重要程度,为公路工程施工安全事故预防提供指导。 相似文献
136.
IntroductionWe present two studies that focus on the relationship between safety rules and the safety climate. It is expected that a reasoned acceptance, namely one based on an understanding of the bases for the rules and a collective management of the rules, should benefit the climate. Method: In an initial study (N = 202) employees replied to a questionnaire that measured the safety climate, the level of the relationship with the safety rules, and the understanding of their bases. The results highlighted the fact that a reasoned acceptance of the rules is associated with an understanding of their bases and predicts the level of safety. In a second study (N = 258) employees replied to a questionnaire measuring team reflexivity, the safety climate, and the level of relationship with the safety rules. We observed that collective management of the rules mediated the relation between team reflexivity and the safety climate. Results: The results are discussed from the point of view of their practical implications. Developing safety climate requires that operators are trained to understand the basis of safety rules and team reflexivity. 相似文献
137.
This study used an experience sampling design to examine the spillover effects of experienced workplace incivility from organizational insiders (coworkers and supervisors, respectively) and organizational outsiders (patients and their visitors) on targets' work‐to‐family conflict and to test the mediating effect of burnout and the moderating effect of display rules. Data collected over five consecutive weeks from 84 full‐time nurses showed that within individuals, weekly experiences of coworker incivility and outsider incivility were positively related to weekly experience of work‐to‐family conflict, and burnout mediated these relationships while controlling for initial level of burnout before participants started a week's work. In addition, display rules, defined as the extent to which individuals perceive they are expected to display desired positive emotions and suppress negative emotions at work, moderated the relationship between outsider incivility and burnout; specifically, the positive relationship between weekly outsider incivility and burnout was stronger for individuals who perceived a higher level of display rules. Our findings contribute to the literature by demonstrating the mediating effect of burnout and the moderating effect of perceived display rules in the relationship between workplace incivility from multiple sources and work‐to‐family conflict from a resource perspective. 相似文献
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140.
This investigation shows how an increased oxygen concentration influences the performance limits of crimped ribbon deflagration flame arresters at elevated pressures. An evaluation of the maximum experimental safe gap (MESG) as reliable criterion for describing the performance limits under non-atmospheric conditions is given. Measurements of MESGs and flame arrester performance tests were performed. Various fuel/oxygen/air mixtures containing ethylene and propane were used as testing gases. Former studies on the pressure dependence and the influence of oxygen on the MESG were initially confirmed. Furthermore, performance tests using a commercial deflagration flame arrester revealed that such a flame arrester may prevent flame transmission also at non-atmospheric conditions within a limited range. For various oxygen concentrations the performance limits were reached at the same MESG. Hence, it can be assumed that a flame arrester possesses a device- and fuel-specific maximum experimental safe gap for a specific gas mixture in different concentrations and at different pressures. This performance-related maximum safe gap can be used as a parameter for estimating and describing the performance limits of a flame arrester. It offers an attempt to simplify the testing and qualification of deflagration flame arresters for non-atmospheric conditions. 相似文献