The influence of iron flow on iron resource efficiency in the steel manufacturing process

An iron resource efficiency is proposed to define a measure of the natural iron resources saved in the steel manufacturing process. A simplified iron flow diagram is presented for the steel manufacturing process. The influences of various deviations in iron flow from the simplified iron flow diagram on iron resource efficiency are analyzed. The relationships between iron resource efficiency of unit processes and the final product are also discussed. As an example, data from a steel plant are used to analyze the influence of iron flow on its iron resource efficiency of finial product in the steel manufacturing process, the influence of iron resource efficiency of unit process on iron resource efficiency of the final product, and give some measures to improve the iron resource efficiency of the steel manufacturing process.     

城市生命线系统的地震网络可靠性研究

震后生命线系统的网络可靠性对于灾后的应急救援和恢复至关重要,因此,评价城市生命线系统网络在一定地震强度下,网络系统保持连通的能力已成为研究生命线地震网络可靠性的重要内容。以经典的系统单元可靠性模型为基础,在众多的网络可靠性计算方法中根据方法实现的难易程度和计算效率,选择采用了不交化穷举集合法和有序二分决策图方法,比较研究了网络系统的可靠性问题,并与Monte Carlo方法进行了对照。此外,针对淮南市配水管网的实际案例,采用上述方法计算了相应的可靠度,计算结果表明,所提方法能够高效地应用于一般的工程实践,具有显著的实用意义。     

TND-PHA法在项目安全管理中的应用

在项目安全管理中,结合项目时间管理中常用的网络图,运用预先危险性分析法对网络图中的每项活动进行分析,根据分析结果制定安全防范措施,并开展有针对性的教育和培训,可以有效避免事故的发生.     

基于方向图的天线分类模型的分析与研究

文章重点考察不同天线在远区场同一接收阵列处的场强大小之间的不同关系特征,并利用神经网络对不同天线的这种非线性特征进行模拟,从而实现基于天线方向图对不同天线的分类,并对不同分类模型进行对比。     

动态主逻辑图--一种改进的安全风险建模方法

用主逻辑图,可以比较直观地建立起复杂系统的安全风险模型,但是这种模型运用的是布尔代数理论,所以无法模拟具有动态行为的系统.动态主逻辑图就是在主逻辑图的基础上,运用模糊数学（逻辑）的理论,分析复杂系统中的动态行为.介绍了动态主逻辑图的8种基本形态,并以利用动态主逻辑图对系统进行全面诊断和描述系统的部分失效的行为为例,简要说明了动态主逻辑图的新特点.     

工程系统一体化安全风险模型研究

借鉴功能模拟原理,利用目标树-成功树-主逻辑图(GTST-MLD)框架,提出了一个一体化安全风险模型。该模型对关联于工程系统安全特性的目标、功能、结构、行为等因素予以综合,提供了从多层次研究解决安全问题的模型基础,克服了基于事件树/故障树模型的概率风险评估等传统方法而分别对系统结构、行为、事件进行研究的问题,支持实现在更高的系统功能层面上对系统安全性的分析研究。通过研究该模型在安全风险评估、事故因果关联分析、潜在交互作用鉴别中的应用,表明研究成果为解决复杂工程系统安全问题提供了新的分析手段。     

老空水水害事故原因分析及防治措施研究

矿井老空水水害一直是困扰煤矿安全生产的不利因素,必须加强其防治措施方面的研究。通过对老空水水害事故的分析,建立了一个系统全面的老空水水害事故的致因鱼刺图模型;并针对鱼刺图模型的各个致因事件提出了老空水防治的具体措施;然后根据安全技术措施等级顺序要求的具体原则,对措施进行等级排序。笔者提出了以下观点老空水的防治是多方位的;防治措施是有等级的;合理设计,严禁剃头开采是消除老空水水害事故的本质安全型措施。     

Wet bench reactive hazards of cleaning stages in semiconductor manufacturing processes

According to the research from FM Global (Factory Mutual Insurance Company), most of the incidents that have occurred in semiconductor plants in the past two decades were reported as “Fire Cases”. They claim that the fires in wet chemical cleaning processes were mainly caused by heater failure. However, depending on the process conditions, electrical heaters are designed to turn off automatically when the temperature reaches a set point. Therefore, a thorough study of the situations related to possible fires in wet chemical cleaning processes is necessary.

This study focused on the incompatible behaviors of cleaning materials used in the wet bench stage. These results can be applied to determine the causes of fires in the wet bench stage from using reactive chemicals for cleaning purposes.

Another purpose of this study was to investigate the potential hazards of widely used chemicals (hydrogen peroxide, concentrated sulfuric acid, hydrochloric acid and isopropyl alcohol) within similar processes in semiconductor plants. Experimental data were also verified in order to establish a concentration triangular diagram, which could be used to identify a combustion, deflagration or even detonation zone. Finally, this study can provide basic design data for an inherently safer process to avoid potential hazards caused by dangerous mixtures, which may result in large property loss in semiconductor plants.     

Zn~(2+)-S~(2-)-H_2O系热力学平衡研究

根据配位化学热力学平衡原理,绘制了温度为298.15K时Zn2+-S2--H2O系pC-pH热力学平衡状态图。结果表明:ZnS溶解平衡时,随着pH值的增加,ZnS的溶解度先减少后增加,当pH值为8.36时,ZnS的溶解度最小,为10-7.69mol/L;Zn(OH)2溶解平衡时,随着pH值的增加,Zn(OH)2的溶解度也呈现先减少后增加,当pH值在9.41时Zn(OH)2的溶解度最小,为10-5.61mol/L;体系中ZnS和Zn(OH)2二者固相溶解平衡时,当S2-Zn2(+mol)时,pH在0～14范围内只生成ZnS沉淀,不会产生Zn(OH)(2s)物质。研究结果可为硫化沉淀法去除废水中锌等技术提供理论依据。