基于理想解和灰关联度的动态评价方法及其应用研究

为了对多个多属性（指标）待评价对象（方案）在多个时间点的发展状态和该时间段内的总体发展水平进行比较分析，根据理想解法和灰关联度法优缺点，提出基于理想解和灰关联度的动态评价方法。该方法基于三维数据，将欧氏距离和灰色关联度相结合，提出一种新贴近度，同时反映了位置关系和数据曲线的相似性差异，兼顾评价指标值差异程度和增长程度。最后将该方法应用于"十二五"期间省域循环经济生态效益评价，通过实例验证该方法实际应用上的有效性。     

灰模糊积分关联度决策模型

灰关联度决策模型是在假设属性之间彼此相互独立的基础上构建的,但是在很多实际问题中属性之间往往存在一定的交互作用,从而导致灰关联度决策模型失效。针对这一问题,引入模糊积分理论,构建了灰模糊积分关联度决策模型。为求解该模型,定义了基于属性权重和属性间交互度的默比乌斯变换系数,来计算2可加模糊测度,其中属性权重通过序关系分析法和施密特正交马田系统共同确定,属性间的交互关系和交互度由专家确定。以廉租房保障家庭经济状况评估为例,对灰模糊积分关联度决策模型和灰关联度决策模型进行比较验证,验证结果表明灰模糊积分关联度决策模型的决策结果更加科学合理,有较好的应用价值。     

基于白化权函数的区间灰数关联度模型

根据区间灰数空间映射思想,引入白化权函数来表征区间灰数的分布信息。定义灰形和灰心分别来描述白化权函数与区间灰数围成的封闭几何图形及其几何重心;定义灰圆和灰径分别来表示以灰心为圆心且与灰形具有相同面积的标准圆及其半径。在此基础上,以灰心序列的横、纵坐标序列为对象,以灰径的离差为权重,依照邓氏关联度原理构造了一个基于白化权函数的区间灰数关联度模型。并针对一种最为典型的白化权函数,具体导出了区间灰数关联度的计算公式。最后,通过一个供应商选择的实例验证了模型的科学性和可行性。基于白化权函数的区间灰数关联度在资源勘探、机器故障诊断、产品品质评价及供应商选择等方面有着广泛的应用前景。     

基于灰色变化率关联度的灰色趋势分析模型的构建及应用

为了考察序列间动态变化趋势的相似性,提出了衡量变化率接近程度的灰色变化率关联度,并讨论了灰色变化率关联度的性质,进而基于变化率关联度提出了灰关联空间分解的新方法。根据行为序列与特征序列变化率正负性的一致性,构建空间分解指数,对灰关联空间进行分解,对特征序列与行为序列进行灰色趋势分析,识别出与特征序列的变化趋势基本保持同步的行为序列。既能够根据变化率关联度对全体行为序列进行排序,也可以在子空间内部再根据变化率关联度进行排序,从而分别在同步子空间与异向子空间识别出关键因素与次要因素。最后将基于变化率关联度的灰色趋势分析应用于阜新煤炭产业集群关键影响因素的识别中,并与其它关联度结果进行了对比分析,验证了本文模型的有效性。     

基于Z值的企业信用等级评价修正灰靶模型

考虑到企业财务信息不确定和样本的非典型分布特征,将灰靶模型引入对企业信用等级的评价;放松经典灰靶模型的各指标变量对靶心影响的等权假设,将z值模型中的Altman系数赋予灰靶指标权重;提出将待评模式与参照模式一起构建灰靶的思路,并在灰靶模型中运用显示分辨域确定分辨系数;为企业信用等级以及其他类似系统的评价提供一个一般化的方法.     

粤、沪、浙、苏四省市大中型工业企业科技创新的灰关联性比较研究

本文以中国科技统计年鉴和粤、沪、浙、苏四省市的统计年鉴(2002～2006年)为依据,通过构建灰关联度模型,对粤、沪、浙、苏四省市的大中型工业企业的科技投入与新产品产出进行灰关联性比较分析,总结出四省市的大中型工业企业科技投入对其科技创新能力的影响差异性,为区域间进行科技创新能力的比较研究提供一个参考。     

基于模糊综合评价的新产品开发项目后评价研究

本文在分析新产品开发项目特征的基础上,采用专家咨询法建立初步的新产品项目后评价指标体系,并运用用灰色关联度分析对评价指标进行合理筛选;然后通过层次分析法,确定各评价指标的权重;最后,采用模糊综合评价构建评价模型,从而为企业新产品开发项目后评价提供了切实可行的依据和评判标准。     

基于有限理性的一级密封价格拍卖灰博弈模型研究——基于准确的价值和经验理想报价估价的最优灰报价模型

运用灰系统理论的思想[1],对目前的一级密封价格拍卖博弈模型进行检验和验证,并对其存在的一些缺陷进行了剖析,认为这些经典模型对条件的限制过于严格,与现实的吻合性较差.基于有限理性假设,设计了经验理想报价灰修正系数,建立了基于准确的价值和经验理想报价估价的有限理性最优灰报价模型.对该模型灰系数进行第一标准灰数变换,找到了投标人的威胁反应灰系数;发现了投标人的最优灰报价不仅取决于其自身的价值,而且还取决于他人的价值及其威胁反应灰系数;投标人的最优灰报价不仅仅刚好为其对被拍物品所认可价值的一半,而要视情而定,一般情况下均高于其所认可价值的一半.对该模型进行了数据仿真,得到一些与经典模型有较大差异的有价值的结论,并建议了投标人的最佳投标模式.     

基于多维时间序列的灰色模糊信用评价研究

传统信用评价技术多在孤立时间点上对受评目标数据进行评价分析,但受评目标由于某些原因可能产生数据"突变",导致评价结果失真,产生信用风险.针对这一问题,本文提出应用多维时间序列数据对受评样本进行信用评价.该方法首先对多维时间序列数据使用灰色关联分析方法进行分割处理,解决"维数灾难"带来的严重影响,并将得到的灰色关联度值作...     

灰色组合预测模型及其应用

针对传统回归模型需要的数据量大且建模复杂等缺陷,提出了一种基于灰色关联度和GM(1,1)的灰色组合预测模型;从灰色关联度的视角寻找数据之间的依赖关系,运用GM(1,1)模型预测数据关系的未来发展趋势,进而建立因变量的预测模型;模型体现了回归分析基于事物因果关系的建模思想,同时又具有灰色理论小样本建模的特点;应用该模型对我国2007和2008年度的GDP进行预测,预测结果表明了该模型的有效性及实用性。     

A Matrix-Based Approach to Uncertainty and Sensitivity Analysis for Fault Trees1

System unavailabilities for large complex systems such as nuclear power plants are often evaluated through use of fault tree analysis. The system unavailability is obtained from a Boolean representation of a system fault tree. Even after truncation of higher order terms these expressions can be quite large, involving thousands of terms. A general matrix notation is proposed for the representation of Boolean expressions which facilitates uncertainty and sensitivity analysis calculations.     

基于灰色关联分析的企业员工满意度评价

本文将灰色理论引入企业员工满意度评价中,建立了基于灰色关联分析的企业员工满意度评价模型。模型采用灰色关联分析法将评价因素间的不完全确知关系进行白化,减少了主观因素的影响,提高了评价结论的准确性,为企业员工满意度评价提供了一种新方法。     

The Ocean Ranger Oil Rig Disaster: A Risk Analysis

This paper analyzes quantitatively the design of the Ocean Ranger off-shore oil drilling rig that capsized and sank on February 15, 1982 off the coast of Canada. A review of the actual disaster is also included based on evidence gathered by the Canadian Royal Commission. The risk analysis includes the construction of a failure modes and effects analysis (FMEA) table, a fault tree, and a quantitative evaluation including common cause failure of the rig components. In the case of the Ocean Ranger ballast control system, it was shown that the analysis was able both to successfully model the catastrophic system failure of the portholes, the actual system failure mode, and identify a common cause failure mode of the pump system. This study represents an application of reliability and risk techniques to the oil services industry.     

Probabilistic Risk Assessment of Wastes Buried in the Ground

The differences between probabilistic risk assessment (PRA) and safety analysis (SA) are discussed, and it is shown that PRA is more suitable than SA for determining the acceptability of a technology. Since a PRA by the fault tree-event tree analysis method used for reactor safety studies does not seem to be practical for buried waste, an alternative approach is suggested using geochemical analogs. This method is illustrated for the cases of high-level and low-level radioactive waste and for chemical carcinogens released in coal burning.     

Internal resource waste and centralization degree in two-stage systems: An efficiency analysis

Internal resource waste refers to the waste in the intermediate resources between the upstream stage and downstream stage in a production or service system. This study examines a system with a two-stage structure, in which the outputs from the first stage are taken as the inputs for the second stage. Two-stage systems can exist in centralized, decentralized, or mixed organizational modes. In this paper, we propose two-stage DEA models considering a degree of centralization that makes it possible to measure internal resource waste in different system modes. Some managerial insights are tested and verified from the perspective of efficiency analysis. We find that: 1) when there is only one intermediate measure in a centralized two-stage system, internal resource waste can be eliminated completely, and 2) a higher degree of centralization in a two-stage system can lead to less internal resource waste and more expected outputs. Finally, we present a numerical example and two practical real-world examples that illustrate our approach and findings.     

粗集的动态特性分析及应用

本文对粗集的动态特性进行了研究,为了比较确切的描述粗集的动态变化程度,本文引入了粗集的结构差离度、贴近度及复杂度等概念,给出了结构差离度和贴近度的性质,最后给出应用背景和实例。     

Probability and Possibility‐Based Representations of Uncertainty in Fault Tree Analysis

Expert knowledge is an important source of input to risk analysis. In practice, experts might be reluctant to characterize their knowledge and the related (epistemic) uncertainty using precise probabilities. The theory of possibility allows for imprecision in probability assignments. The associated possibilistic representation of epistemic uncertainty can be combined with, and transformed into, a probabilistic representation; in this article, we show this with reference to a simple fault tree analysis. We apply an integrated (hybrid) probabilistic‐possibilistic computational framework for the joint propagation of the epistemic uncertainty on the values of the (limiting relative frequency) probabilities of the basic events of the fault tree, and we use possibility‐probability (probability‐possibility) transformations for propagating the epistemic uncertainty within purely probabilistic and possibilistic settings. The results of the different approaches (hybrid, probabilistic, and possibilistic) are compared with respect to the representation of uncertainty about the top event (limiting relative frequency) probability. Both the rationale underpinning the approaches and the computational efforts they require are critically examined. We conclude that the approaches relevant in a given setting depend on the purpose of the risk analysis, and that further research is required to make the possibilistic approaches operational in a risk analysis context.