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31.
以不停航施工为特定情景,构建SD模型对机场安全风险的发生及作用机理进行研究。首先采用鱼骨图识别不停航施工情景下的机场安全风险,得到不停航施工情景下的机场安全风险共包括22个关键影响因子;然后采用因果关系图分析安全风险的影响关系,并运用SD模型软件Vensim PLE构建不停航施工情景下的机场安全风险SD模型流图,分析风险的作用机理,得到各风险因子相互作用形成5个主要的风险回馈循环;最后从机场层面、政府层面、施工企业层面三方面着手,提出了具体管理建议。该研究丰富了不停航施工情景下的机场安全风险方面的理论研究,可为减少不停航施工情景下的机场安全风险、完善民用机场安全风险管理体系提供参考。  相似文献   
32.
整理和分析兴济1井的静水位观测以来的水位和气压观测资料,发现该井水位线性下降趋势明显,存在峰谷形式的年变周期,滑动速度分析显示出一定的异常信息;数据散点图显示水位观测结果受固体潮影响大,滑动分析显示固体潮规律畸变时可能存在前兆信息;主要的异常前兆表现形式为水位的下降方向脉冲,可能与井址附近区域或者井址北东方向的天津和唐山老震区相关断裂带上的地震活动有关.  相似文献   
33.
ABSTRACT: It was found that the conventional weighting factor application to hyetograph ordinates results in artificially attenuated storm patterns. A modified weighting procedure is suggested which allows adjustments in the storm timing, peak intensity, and volume but conserves the storm pattern observed at the raingage nearest to the watershed point of interest. The systematic underestimation of peak flood flows, which result from conventional hyetograph weighting, can be avoided by conserving the hyetograph shape from the raingage nearest to any subarea of a modeled watershed and merely applying weighting factors to the rainfall volumes and temporal center of gravity of several hyetographs.  相似文献   
34.
ABSTRACT. In the last decade much research has been devoted to applying the systems analysis approach to water resources problems. A popular research goal has been determination of the “best” method of operating a multipurpose reservoir. The goal of this study was to derive the economically optimum flood control diagram for a multipurpose reservoir by systems analysis. The technique employed to optimize the flood control diagram was programmed so that the optimization process could be applied to other multipurpose reservoirs. Two computer programs developed at the U.S. Army Corps of Engineers' Hydrologic Engineering Center were utilized with modifications to simulate the operation of Folsom Reservoir in central California. Economic analyses were incorporated along with an optimization technique into the reservoir operations program; and the resultant program was capable of routing a sequence of monthly reservoir inflows, computing benefits for various flood control diagrams (as dictated by the optimization procedure), and selecting the economically optimum flood control diagram. The univariate gradient technique was the optimization procedure employed. The two computer programs are on file at the Hydrologic Engineering Center in Davis, California.  相似文献   
35.
This paper presents the technical model of an Integrated Quantitative Risk Assessment method, taking into account management as well as technical design and producing risk level measures. The basic steps of the technical model consist in developing a Master Logic Diagram (MLD) delineating the major immediate causes of Loss of Containment and associated quantitative models for assessing their frequency. Appropriate management models quantify the parameters of the technical model on the basis of the safety management system of the installation. The methodology is exemplified through its application on the risk assessment of a LPG scrubbing tower of an oil refinery. A detailed technical model simulating the response of the system to various initiating events is developed, along with a detailed model simulating the influence of the plant-specific management and organizational practices. The overall effect is quantified through the frequency of release of LPG as a result of a Loss of Containment in scrubbing towers of the refinery.  相似文献   
36.
MATLAB加VB实现实验室质量控制图的绘制   总被引:1,自引:0,他引:1  
阐述了质量控制图在实验室质量控制中的作用和存在的问题,提出应用Visual Basic的界面设计功能,以及MATLAB的计算和图形处理功能,通过在VB中以ActiveX组件方式调用 MATLAB对象的属性和方法,实现质量控制中复杂的数据统计和图表的制作功能.并对《环境水质监测质量保证手册》中的各类质控图进行了实例示范.  相似文献   
37.
高速铁路列车运行冲突管理研究现状综述   总被引:3,自引:2,他引:1  
在定义高速铁路列车运行冲突的基础上,分析列车运行冲突的产生机理,从4个不同角度对列车运行冲突进行分类。归纳并分析列车运行冲突管理的研究历程及国内外对列车运行冲突管理问题研究的现状。分析表明,国内外对列车运行管理的研究主要是依托列车运行图优化和调度指挥系统开发而进行的,对列车运行冲突管理的专门和系统研究尚缺,没有适合我国国情和路情的高速铁路列车运行冲突管理体系。指出冲突分析、冲突化解和基于冲突管理的列车运行调整方法及运行图优化技术等问题是我国高速铁路冲突管理的主要内涵,将时变性、冲突可蔓延性、分割管理和复杂性等归结为高速铁路冲突管理的特点。  相似文献   
38.
39.
Engineering line diagram (ELD) development forms a distinct phase in process plant design. It is a complex and expensive activity and as such warrants considerable effort to minimise costs and maximise effectiveness. In this paper, the nature of the ELD design task is analysed in order to understand how it could be carried out more effectively. A number of shortfalls in current practice are discussed. These shortfalls were identified through a combination of the following activities: a review of the literature; a survey of current practice and follow-up line diagram development exercise; and task analysis work carried out at ICI. The most significant findings of the survey of current practice are presented. It is proposed that the shortfalls identified can be overcome by introducing structure to the design task. The manner in which this can be achieved is the subject of the second part of this paper.  相似文献   
40.
系统分析、核定了沈阳市铁西区水污染物排放总量,通过对排污总量的可靠性分析和度量,提出了提高系统信息可靠性的监测与改进建议.认为加强泵站信息的监测与调查有利于对重金属类污染物实施总量控制;而且,在此基础上追加细河黄蜡坨子断面的监测不仅可以清晰识别细河入浑河的排污量,而且可以对有机污染物进行总量控制作出有针对性的、及时的反应.  相似文献   
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