A fuzzy reasoning and fuzzy-analytical hierarchy process based approach to the process of railway risk information: A railway risk management system

Risk management is becoming increasingly important for railway companies in order to safeguard their passengers and employees while improving safety and reducing maintenance costs. However, in many circumstances, the application of probabilistic risk analysis tools may not give satisfactory results because the risk data are incomplete or there is a high level of uncertainty involved in the risk data. This article presents the development of a risk management system for railway risk analysis using fuzzy reasoning approach and fuzzy analytical hierarchy decision making process. In the system, fuzzy reasoning approach (FRA) is employed to estimate the risk level of each hazardous event in terms of failure frequency, consequence severity and consequence probability. This allows imprecision or approximate information in the risk analysis process. Fuzzy analytical hierarchy process (fuzzy-AHP) technique is then incorporated into the risk model to use its advantage in determining the relative importance of the risk contributions so that the risk assessment can be progressed from hazardous event level to hazard group level and finally to railway system level. This risk assessment system can evaluate both qualitative and quantitative risk data and information associated with a railway system effectively and efficiently, which will provide railway risk analysts, managers and engineers with a method and tool to improve their safety management of railway systems and set safety standards. A case study on risk assessment of shunting at Hammersmith depot is used to illustrate the application of the proposed risk assessment system.     

Identification and classification of ERP critical failure factors in Iranian industries

Implementation of Enterprise Resource Planning systems (ERPs) is a complex and costly process, which usually results in serious failures. The majority of previous studies and research projects have been conducted in identifying ERP Critical Success Factors (CSFs) rather than Critical Failure Factors (CFFs). On the other hand, most studies have been devoted to developed countries, while in developing countries, many companies have moved towards using such systems. The majority of IT/IS management standards and guidelines have been developed by technologically-leading countries. But developing countries, which mostly confront with especial challenges, have a different condition from the implicit assumptions of leading countries. Iran is one of these countries that many of its ERP implementation projects led to failure. There is no comprehensive study that identifies ERP CFFs in Iranian industries. The main purpose of this study is to identify such factors and classify them to help other industries, consultants and implementers to prevent failures in the implementation of ERP projects. So, at first, with the semi structured interviews and literature reviews, 47 failure factors were identified. After that a questionnaire developed and sent to ERP project team members in Iranian industries that failed in their ERP projects. Robust Exploratory Factor Analysis (EFA) has been used for data analysis, which finally classified critical failure factors in seven groups named as vendor and consultant, human resources, managerial, project management, processes, organizational and technical. The results of this study have provided a very useful reference for scholars and managers to identify the relevant issues of ERP projects failure in developing countries.     

德国迪林根ROGESA钢铁公司2号烧结机EFA(R)烟气处理系统及其运转情况

多年来,环境保护一直是烧结行业的一个重要课题.由于政府部门提出了更加严格的要求,烧结厂废气的进一步净化已经变得很有必要.一套新开发的、工业化的EFA(曳流吸收塔)烟气处理系统于2006年年中在ROGESA钢铁公司投入运行.本文就该系统的工艺流程、特点及运行情况作一介绍.     

改进的射极跟随器增广电流镜

本文提出了一种适用于数模混合电路的低压、大电流比电流镜结构.这种电流镜结构在传统射极跟随器增广电流镜的基础上进行改进,添加一个用作射极跟随器的PNP管.和传统射极跟随器增广电流镜一样,其最小输入电压不仅取决于输入电流范围,还与连接在两镜像管发射极的负反馈电阻(用以提高精度)的大小有关.在射极负反馈电阻对应相等的情况下,工作在合适偏置电流下的改进电流镜不仅输入电压比传统射极跟随器增广电流镜低一个PN结导通电压,其精度也要比传统结构的高.     

Starch Gelation Process Observed by FT-IR/ATR Spectrometry with Multivariate Data Analysis

For directly observing changes related to the gelation process of starch, IR spectra of starch in water while heating were obtained using FT-IR/ATR spectrometry. Relationships between gelation and spectral changes were examined using factor analysis, evolving factor analysis (EFA) and three-way principal component analysis (PCA). Absorption at 3300 and 1610 cm^-1 decreased with temperature but absorption at 1000 cm^-1 increased. The factor score plot patterns of amylose, amylopectin and rice starches were similar but those of potato and corn starches were unique. EFA indicated variances relating to changes caused in starch and water as different factors. Loadings of the starch component 2 in three-way PCA correlated with starch granule sizes.     

我国企业信息化建设测度体系实证研究

信息化建设测评是企业有效地进行信息化管理的前提,而信息化测评体系设计的成败在很大程度上取决于能否合理地综合选择信息化成熟度模型的研究成果。利用探索性因子分析和验证性因子分析,可以对基于理论框架所建立的测评模型进行实证检验,验证其有效性与实用性。同时可以根据验证结果对我国企业信息化建设的现状及存在的问题进行合理的判断。     

声振系统中高频能量流分析法研究进展

能量流分析法是预测声振系统中高频动力响应的一种有效手段,该方法引入的假设条件较少,并可基于声振系统的几何模型计算随空间变化的稳态动力响应,应用上具有很大的优点。本文首先回顾了不同结构件（包括杆、梁、板及复合结构）各种波场的能量微分方程及其理论基础的发展过程,然后,针对不同类型的声振系统耦合形式,包括结构/结构耦合,结构/流体耦合及其它耦合情况,说明了基于能量流分析的耦合问题处理方法的发展,最后,说明了计算随机激励下声振系统响应的随机能量流分析法的相关研究,以及其与经典统计能量分析法间理论关系研究的进展情况。     

渐进因子分析法及其在Au/Ni/Si薄膜俄歇深度剖面研究中的应用

将渐进因子分析法应用于俄歇深度剖面的化学态研究。通过对Au／Ni／Si薄膜样品深度剖析过程的渐进因子分析，最终获得了各元素的化学状态和深度分布，并发现Au／Ni／Si样品中Ni／Si界面在室温下已发生反应，生成富Si的NixSi化合物层。样品经真空退火处理后，Ni／Si界面进一步反应生成Ni2Si合金，而原有的NixSi化合物含量相对减少，并向Si基体侧扩展，同时Ni穿透Au膜在样品表面富集。渐进因子分析的结果与XPS分析相一致。     

Experimental evaluation of the effect of the incidence angle and consolidation pressure on the hydraulic resistance capacity of clayey soils

The primary aim of this study is to examine the variations in erosion and hydraulic resistance capacity of clayey soils with a changing water flow under variable flow conditions. Clayey soils were artificially prepared with various kaolin-sand ratios and consolidation pressures. A laboratory flume apparatus, called an erosion function apparatus (EFA), is improved to measure the scour rate and critical shear stress of samples with changing water flow directions. A series of tests that use the improved EFA was performed for artificial clayey soils considering various directional changes in the water flow at incidence angles of 0°, 90°, 135°, and 180°. Based on the test results, the undrained shear strength indicated the highest correlation with the critical shear stress. Furthermore, the critical shear stress decreased and the scour rate increased with an increasing incidence angle. Finally, the characteristics of the hydraulic resistance capacity, the variations in critical shear stress, and the scour rate changed with the magnitude of consolidation pressure of the clayey soils.     

Modelling and analysis of FMS productivity variables by ISM,SEM and GTMA approach

Productivity has often been cited as a key factor in a flexible manufacturing system (FMS) performance, and actions to increase it are said to improve profitability and the wage earning capacity of employees. Improving productivity is seen as a key issue for survival and success in the long term of a manufacturing system. The purpose of this paper is to make a model and analysis of the productivity variables of FMS. This study was performed by different approaches viz. interpretive structural modelling (ISM), structural equation modelling (SEM), graph theory and matrix approach (GTMA) and a cross-sectional survey within manufacturing firms in India. ISM has been used to develop a model of productivity variables, and then it has been analyzed. Exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) are powerful statistical techniques. CFA is carried by SEM. EFA is applied to extract the factors in FMS by the statistical package for social sciences (SPSS 20) software and confirming these factors by CFA through analysis of moment structures (AMOS 20) software. The twenty productivity variables are identified through literature and four factors extracted, which involves the productivity of FMS. The four factors are people, quality, machine and flexibility. SEM using AMOS 20 was used to perform the first order four-factor structures. GTMA is a multiple attribute decision making (MADM) methodology used to find intensity/quantification of productivity variables in an organization. The FMS productivity index has purposed to intensify the factors which affect FMS.