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301.
工业企业电气安全评价方法研究 总被引:8,自引:0,他引:8
针对现行电气安全评价方法存在的不足,提出了工业企业电气安全模糊综合评价方法.依据事故理论的综合论观点,建立了多层次电气安全评价因素体系;采用定性与定量相结合的层次分析法(AHP)确定评价因素的权重;采用隶属频率统计法确定单因素隶属度;最后应用多层次模糊综合评判模型合成评价结果,并使用安全等级特征量对模糊综合评价结果进行处理,得出工业企业电气系统的安全等级.结果表明,将模糊综合评价方法引入工业企业电气安全现状评价具有一定的现实意义,克服了现行评价方法不够全面或不够定量的缺点;安全等级模糊特征量是处理模糊综合评价结果更优化的方法;该评价方法紧密结合企业现状,可在一般工业企业的电气安全评价中广泛应用,其配套评价软件更为企业安全管理部门和安全评价机构提供了便捷的应用工具. 相似文献
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Based on the theory of gas-solid two-phase flow and the characteristics of cavern stope a model of dust migration was established. The dust concentration changing of cavern stope by ventilation in 20 min after blasting and the dust trajectory in different wind speed were simulated by Fluent Software. The results show that distribution of dust concentration is significantly affected by flow field of airway in cavern, and the dust concentration of inlet is higher than that of outlet and the highest one on the corner of inlet’s side. In the stope, the smaller the wind speed of inlet is, the shorter of dust can be captured, settled and discharged, the more obviously affected by the trajectory of gas flow field. It goes into the stage of clean cycle emissions after 60 s, the speed of dust concentration dropped is the biggest between 0 s and 70 s, the main dust in stope is respirable dust after 70 s, it needs much time to settlement.According to the measured data of metal mining, approximately 87% of dust was generated during the drilling and blasting in the mine (Wang, 1979). A lot of dust with high concentrations was produced during the cavern stope blasting and it was difficult to be discharged. It can help choose the right speed to rule out the dust quickly which produced during cavern blasting, if the dust concentration distribution and the dust migration law of different inlet velocity in the cavern can be verified, what’s more, the labor productivity can be increased. It has great significance for choosing reasonable ventilation parameters, reducing dust hazards of stope to researching the dust concentration distribution regularity in the stope. 相似文献
306.
Nishant Pandya Nadine Gabas Eric Marsden 《Journal of Loss Prevention in the Process Industries》2012,25(1):20-32
We present the results of a parametric sensitivity analysis of a widely used model for atmospheric dispersion of toxic gases, in order better to understand the influence of user-adjustable parameters on model outputs. We have studied 60 min continuous release scenarios for three different products (nitric oxide, ammonia and chlorine), chosen to cover a range of physical characteristics and storage conditions. For each product, we have broken down base-case scenarios into a number of sub-scenarios corresponding to different release conditions which determine physical phenomena (flow rate, release angle, release elevation and atmospheric stability class). The use of statistical tools to analyze the results of a large number of model executions allows us to rank model parameters according to their influence on the variability of a number of model outputs (distances and concentrations), on a per-scenario and per-product basis. Analysis of the results allows us to verify our understanding of the modeling of cloud dispersion. 相似文献
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为便于矿山管理人员操作使用,清晰了解采空区内空气流动的状态及各气体组分的浓度分布,防火防瓦斯耦合措施效果,同时考虑到基于绘图功能强大的AutoCAD及CFD技术开发了适合采空区的风火瓦斯耦合模拟软件,提供了采空区绘制、通风、注氮、闭墙、瓦斯钻孔、漏风源汇等图元,可对采空区流场进行数值模拟分析,优化通风参数,降低采空区自然发火的可能,并能优化矿山防瓦斯防灭火方案,对矿山的安全管理采空区具有指导意义。 相似文献
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ABSTRACT: Common constraints in using existing mathematical models are the lack of appropriate input data and inadequate time and money to perform the modeling. A decision support system was developed to aid in selecting inputs to a basin scale soil and water resources model. The system prompts users for input values and formats them in the model input file. The system also accesses large data bases, interfaces with expert systems, gives explanations, suggests default values, and provides graphics. Technology transfer will be enhanced by decreasing the time and money spent during model use and increasing user confidence in the model. 相似文献
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Chains of accidents, in literature generally referred to as domino effects, knock-on effects, cascade effects or escalation effects occur very infrequently but with disastrous consequences. There exist very few software packages to study such domino accidents in complex industrial areas and to forecast potential catastrophes caused by secondary order (involving a sequence of three installations submitted to two consecutive accidents), tertiary order or even higher order accidents. Moreover, available domino software focuses on risk assessment and on consequence assessment. None of these toolkits specifically addresses the prioritization of installation sequences in an industrial area in order to facilitate objective prevention decisions about domino effects. This paper describes the application of a new computer-automated tool designed to support decision-making on preventive and protective measures to alleviate domino effects in a complex surrounding of chemical installations. Using a holistic approach and thus looking at the entire industrial area as a whole, all sequences of three installations in the area are ranked according to their danger contribution to domino effects. An example of a cluster of chemical plants demonstrates the level of qualitative and quantitative input data required. The example is also used to explain the toolkit results, as well as the surplus value and the benefits for company safety managers and regulators. 相似文献
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污水处理厂原始数据可靠性评价方法 总被引:1,自引:1,他引:0
利用生物营养物去除(BNR)实验室试验系统,建立了物料平衡关系矩阵,并借助于Macrobal软件对原始运行数据进行深入检查和可靠性评估.结果表明,物料平衡检查过程不仅能发现并修正测量中隐藏的大误差,准确地确定污泥龄(SRT);此外,还能得出COD的氧化量(OCCOD)、硝化量(Qnitr)、反硝化量(Qdeni)及氧的净消耗量(OCnet)等开放平衡数据.其中,准确的污泥龄(SRT)是获得良好模拟预测效果的关键,反硝化量(Qdeni)将为反硝化过程的校正提供可靠依据,氧的净消耗量(OCnet)可用于模型校正的最终检验过程. 相似文献