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1.
Based on the analysis about the hydrogeological conditions and engineering geological conditions, this paper makes analysis on the possible risks of the deep overlying stratum foundation and establishes the risk evaluation index system during the foundation operating period. Such methods as analytic hierarchy process (AHP), Delphi method and fuzzy comprehensive evaluation method are adopted to make the quantitative analysis on the risk factors and establish the risk judgment model. According to the actual engineering of Taizhou Bridge, the paper evaluates the risk of the foundation during the operating period at the condition of deep overlying stratum. The evaluation results can provide the reference for the risk management of the bridge foundation during the operating period.  相似文献   

2.
Fuzzy Set-Based Risk Evaluation Model for Real Estate Projects   总被引:3,自引:0,他引:3  
With the rapid development of residential real estate market, risk evaluation has been an important task in the process of project. This paper describes a risk evaluation method for residential real estate projects based on fuzzy set theory which uses linguistic variables and respective fuzzy numbers to evaluate the factors. The primary weights of factors and evaluation of alternatives are determined by applying linguistic variables and fuzzy numbers. The notion of Shapley value is used to determine the global value of each factor in accomplishing the overall objective of the risk evaluation process, so the primary weights are revised, thus the importance of factors can be reflected more precisely. A major advantage of the method is that it allows experts and engineers to express their opinions on project risk evaluation in linguistic variables rather than crisp values. An illustration is presented to demonstrate the application of the method in risk evaluation. The results are consistent with the results calculated by conventional risk evaluation method. The research demonstrates that the method is objective and accurate, and is of an application value in the risk evaluation for residential real estate project.  相似文献   

3.
董淑芳 《科技信息》2013,(8):184-184
A clear picture could be finished from Alkin's(2011) book that attention should be paid to the understanding of and perspectives on program evaluation.To start with,one can have a better understanding of the concept of"program evaluation".  相似文献   

4.
Under the underdetermined blind sources separation ( UBSS) circumstance, it is difficult to es-timate the mixing matrix with high-precision because of unknown sparsity of signals.The mixing ma-trix estimation is proposed based on linear aggregation degree of signal scatter plot without knowing sparsity, and the linear aggregation degree evaluation of observed signals is presented which obeys generalized Gaussian distribution ( GGD) .Both the GGD shape parameter and the signals’ correla-tion features affect the observation signals sparsity and further affected the directionality of time-fre-quency scatter plot.So a new mixing matrix estimation method is proposed for different sparsity de-grees, which especially focuses on unclear directionality of scatter plot and weak linear aggregation degree.Firstly, the direction of coefficient scatter plot by time-frequency transform is improved and then the single source coefficients in the case of weak linear clustering is processed finally the im-proved K-means clustering is applied to achieve the estimation of mixing matrix.The proposed algo-rithm reduces the requirements of signals sparsity and independence, and the mixing matrix can be estimated with high accuracy.The simulation results show the feasibility and effectiveness of the al-gorithm.  相似文献   

5.
By constructing evaluation indicator system of sustainable land use of Tibet from three aspects of ecological environment, economic development, resources and social advancement, this article studies the following contents respectively in two dimensions of time and space: the changes of sustainable land use of Tibet in recent 20 years and spatial characteristics of sustainable land use of Tibet in 2002. The following conclusions can be drawn from evaluation results .① With regard to com- prehensive evaluation value of sustainable land use, the trend of Tibet sustainable land use evaluation values from 1983 to 2002 are very close to the comprehensive evaluation values of ecological environment, which is up trend; ② sustainable utilization degree of land use in eastern region of Tibet is much higher than that of western region. ③ the sustainable land use evaluation value of Nyingtri County is the highest, and the counties with relatively higher land sustainable use values include Lhasa, Lhoka, Chamdo. While Nakchu, Ngari, Shigatse counties have the relatively lower evaluation values; ④ By analyzing each evaluation indicator's weight on sustainable land use, it can be concluded that the key limiting factors of sustainable Tibet land resource utilization are land desertification, grassland degradation and low economic level.  相似文献   

6.
A new method for Web users fuzzy clustering based on analysis of user interest characteristic is proposed in this article. The method first defines page fuzzy categories according to the links on the index page of the site. then computes fuzzy degree of cross page through aggregating on data of Web tog. After that, by using fuzzy comprehensive evaluation method, the method constructs user interest vectors according to page viewing times and frequency of hits. and derives the fuzzy similarity matrix from the interest vectors for the Web users. Finally. it gets the clustering result through the fuzzy clustering method. The experimental results show the effectiveness of the method.  相似文献   

7.
Moldability evaluation for molded parts,which is the basis of concurrent design,is a key design stage in injection molding design.By moldability evaluation the design problems can be found timely and an optimum plastic part design achieved.In this paper,a systematic methodology for moldability evaluation based on fuzzy logic is proposed.Firstly,fuzzy set modeling for six key design attributes of molded parts is carried out respectively.Secondly,on the basis of this,the relationship between fuzzy sets for design attributes and fuzzy sets for moldability is established by fuzzy rules that are based on domain experts‘ experience and knowledge.At last the integral moldability for molded parts is obtained through fuzzy reasoning.The neural network based fuzzy reasoning approach presented in this paper can improve fuzzy reasoning efficiency greatly,especially for system having a large number of rules and complicated membership functions.An example for moldability evaluation is given to show the feasibility of this proposed methodology.  相似文献   

8.
Based on the study of visitors‘ individual spatial behaviors, a tourists‘ spatial behavior simulator (TSBS) to assess the carrying capacity of tourist resorts was developed, TSBS employs GIS (Geographic Information System) to manage the spatial data, and Multi-Agent system to simulate the actions of individual visitors. By utilizing TSBS, visitors‘ travel patterns such as location, cost, and state can be analyzed and predicted. Based on this analysis and prediction, the model of assessing the carrying capacity of resorts is built. Our results show that TSBS will be an effective tool to accurately assess the carrying capacity of tourist resorts.  相似文献   

9.
Modification of a fuzzy partition often leads to the change of fuzziness of a fuzzy system. Researches on the change of fuzzy entropy of a fuzzy set, responding to shape alteration of membership function, therefore, play a significant role in analysis of the change of fuzziness of a fuzzy system because a fuzzy partition consists of a set of fuzzy sets which satisfy some special constraints. This paper has shown several results about entropy changes of a fuzzy set. First, the entropies of two same type of fuzzy sets have a constant proportional relationship which depends on the ratio of the sizes of their support intervals. Second, as for Triangular Fuzzy Numbers (TFNs), the entropies of any two TFNs which can not be always the same type, also, have a constant proportional relationship which depends on the ratio of the sizes of their support intervals. Hence, any two TFNs with the same sizes of support intervals have the same entropies. Third, concerning two Triangular Fuzzy Sets (TFSs) with same sizes of support intervals and different heights, the relationship of their entropies lies on their height. Finally, we point it out a mistake that Chen's assertion that the entropy of resultant fuzzy set of elevation operation is directly to that of the original one while elevation factor just acts as a propartional factor. These results should contribute to the analysis and design of a fuzzy system.  相似文献   

10.
A fuzzy set-based evaluation approach is demonstrated to assess the security risks for internet-banking System. The Internet-banking system is semi-formally described using Unified Modeling Language (UML) to specify the behavior and state of the system on the base of analyzing the existing qualitative risk assessment methods. And a quantitative method based on fuzzy set is used to measure security risks of the system, A case study was performed on the WEB server of the Internet-banking System using fuzzy-set based assessment algorithm to quantitatively compute the security risk severity. The numeric result also provides a method to decide the most critical component which should amuse the system administrator enough attention to take the appropriate security measure or controls to alleviate the risk severity. The experiments show this method can be used to quantify the security properties for the Internet-banking System in practice.  相似文献   

11.
 随着用户对供电质量要求的提高,配电系统的可靠性评价问题也越来越受到人们的重视。在分析配电系统可靠性问题的基础上,提出了配电系统可靠性评价的可变模糊方法。该方法首先根据指标特征值、指标评价区间矩阵、可变范围评价区间矩阵及点值矩阵确定相对隶属度矩阵,然后利用可变模糊评价模型对样本进行综合评价,得到样本在各级别下的综合相对隶属度,进而计算级别特征值,并以此为依据进行评价。可变模糊方法可以科学地确定样本指标对各级指标标准区间的相对隶属度,并且能够通过变化模型及其参数,合理地确定出样本的评价等级,提高对样本等级评价的可靠度。通过对某地区配电系统进行评价,得出其级别特征值比较稳定,总体评价结果为合格。结果表明,可变模糊评价方法可靠,可用于配电系统可靠性评价。  相似文献   

12.
为解决考虑拉索腐蚀程度的既有预应力空间索杆系结构安全评价技术难题,研究建立了基于结构自身特性和拉索腐蚀程度的安全性客观评价方法。首先,建立了空间索杆系在瞬间断索下的动力响应分析方法,并通过三索结构算例验证了该方法的合理性和可行性;其次,根据判断矩阵构建理论和断索分析结果,建立了考虑拉索腐蚀程度的索杆系中各拉索权重系数确定方法;在此基础上,建立了拉索腐蚀程度的隶属函数,构建拉索索系的安全评语集,根据权重系数和拉索腐蚀程度检测结果,建立了既有预应力空间索系安全性的模糊综合评价体系。依托于某基于空间索杆系结构,对所构建的权重确定方法、隶属度函数和模糊综合评价模型进行了初步的应用和合理性验证。  相似文献   

13.
模糊多级综合评判在专利资产评估中的应用   总被引:1,自引:0,他引:1  
提出一种评估专利资产价值的新方法,它克服了使用收益法时所考虑因素影响的不确定性。首先分级罗列出影响专利资产估价的主要因素,采用专家调查法对各指标体系中的影响因素赋权,得出评判矩阵;用模糊数学原理建立三级模糊综合评判模型对具体的专利资产进行分析,得出最终模糊集;再采用等级参数法确定参数价格列向量,得到专利资产的价值。最后以某公司内螺纹铜管专利技术评估为例,对其进行评估并得到合理的评估值。  相似文献   

14.
ThebenefitofinvestmentforalargerscaleWSISiscloselyrelatedtoreasonableplanninganddesigning ,andtheim portantrequirementforplanninganddesigningistodecidewhichirrigationtechniquewillbeusedforWSISatfirst[1 ] .Manyfac torshavetobeconsideredinthestageofplanning ,andmostofthemarehardtobeanalyzedquantitativelynowadays[2 ,3] ,theexperiencesofexpertsanddecisionmakersplayleadingroles,butthiswoulddeviatefromobjectiverealityowingtothedecisionmakersaredifficulttoavoidasubjectivityandone sidedview[4] .Bec…  相似文献   

15.
提出了一种对结构可靠性进行鉴定的新方法,该方法采用了人工智能技术来减少鉴定的主观性.由于对结构可靠性的认识存在一定的模糊性,采用了多级模糊综合评判进行可靠性鉴定.根据现行鉴定规程,将结构系统分为构件、子单元、鉴定单元三个层次.首先,利用训练后的神经网络求出构件对于不同可靠性等级的隶属度,然后通过多级模糊综合评判求得子单元及鉴定单元对于不同可靠性等级的隶属度.同时,对于检测参数的选取也进行了讨论.图2,表2,参8.  相似文献   

16.
矿区开发对水资源影响较大,故开展矿区水资源承载力研究具有重要意义。以晋城矿区为例,采用模糊综合评价法,分析了晋城矿区水资源承载力情况。结果显示:晋城市水资源承载力处于中等偏好水平;矿区废水回用对提高矿区水资源承载力具有重要作用。  相似文献   

17.
煤与瓦斯突出预测层次分析-模糊综合评判方法   总被引:12,自引:1,他引:12  
将层次分析和模糊综合评判方法结合起来应用于煤与瓦斯突出预测研究中.运用层次分析法确定了煤与瓦斯突出各影响因素权重系数,采用隶属函数构造了单因素判别矩阵,并运用模糊综合评判法建立了煤与瓦斯突出预测模型. 对平顶山研究区典型工作面进行了瓦斯突出危险性的定量预测和突出等级划分.结果表明,应用层次分析-模糊综合评判方法预测煤与瓦斯突出强度是可行的.  相似文献   

18.
针对起重机金属结构安全评价时确定相对隶属度的不足和最大隶属度原则不适用的问题,提出了以组合赋权法和可变模糊集理论相结合的评价方法。该方法将评价指标的评分结果转化为评价向量,依据可变模糊集理论中的相对差异度函数确定相邻两级指标的相对差异度;利用层次分析法和信息熵法分别确定起重机金属结构的主观和客观权重,运用集对联系数融合主客观权重;由组合权重和相对差异度矩阵确定综合相对隶属度,并通过变换组合参数进行综合评价,同时经计算得到评价对象的安全等级;最后,以某造船门式起重机金属结构变形缺陷的评价为例,验证了该模型的合理性和可行性。  相似文献   

19.
根据安全评价理论、风险评估理论,通过专家调查方式确定影响船舶适航性的评价指标并按照重要程度进行分类,然后采用判断矩阵法计算评价指标的权重,运用模糊集合理论确定隶属函数,进而建立数学模型,实现对船舶适航性的模糊综合评价.结果表明评价模型及其评价结果与实际情况基本吻合.  相似文献   

20.
研究厂房可靠性模糊综合评判法的基本原理与(操作)方法.结合厂房的结构特点,将模糊评判应用到厂房鉴定中.通过确定影响结构可靠性模糊变量的隶属度,形成损伤或破坏因素的评价矩阵,采用三级模糊推理逻辑运算,判定厂房结构的可靠性.通过一个工程实例,将模糊综合评判法与现行规范评判法进行比较.结果表明利用模糊综合评判法所得到的计算结果信息量大、直观性强,具有更高的可信度.  相似文献   

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