模糊同余关系下的模糊粗糙群的同态

从群上的模糊正规子群与完备模糊同余关系的对应出发,研究模糊同余关系下的模糊粗糙群与模糊粗糙商群的同态关系.即在一定条件下,满同态能保持模糊同余关系的结果.进一步补充和丰富了模糊集与粗糙集的交叉理论.     

模糊矩阵的分解定理

从模糊矩阵的定义与λ-截矩阵的定义出发,提出一种数与模糊矩阵的乘积运算,通过这个运算建立了模糊矩阵的分解定理,得到了模糊矩阵与截矩阵之间的转化关系和一类经典集合矩阵与模糊矩阵之间的转化关系,并讨论了数与模糊矩阵的乘积运算的性质.     

直流调速系统模糊控制器设计

传统的转速-电流双闭环直流调速系统结构简单、设计较为方便,在工业中得到了广泛的应用。然而由于PI控制算法的局限性,使得传统直流调速系统鲁棒性较差,不能满足高精度动态性能应用场合的控制要求。本文采用Fuzzy(模糊)—PID复合控制方式,把转速的偏差的大小的绝对值和偏差变化率的绝对值作为模糊控制器的输入,用来调整转速环节PID控制器、、三个参数,实现控制器参数的在线自调整功能。仿真说明了所用方法的有效性。     

模糊数学在矿区环境可持续发展评价中的应用

矿区环境问题已经成为影响区域可持续发展的重要因素,越来越引起人们的重视。本文引入模糊数学综合评价方法对矿区环境可持续发展的现状进行定量的评价,得出该矿区环境可持续发展的综合评价等级,为及时发现矿区环境可持续发展存在的隐患和缺陷、制定相应的措施奠定基础。     

Fuzzy-based risk prioritization for a hydrogen refueling facility in Malaysia

Hydrogen is starting to be mentioned as an alternative fuel to replace the fossil fuel in future transportation applica- tions due to its characteristics of zero greenhouse gas emission and high energy efficiency. Before hydrogen fuel and its facilities can be introduced to the public, relevant safety issues and its hazards must be assessed in order to avoid any chance of injury or loss. While a traditional risk assessment has difficulty in prioritizing the risk of failure modes, this paper proposes a new fuzzy-based risk evaluation technique which uses fuzzy value to prioritize the risk of various scenarios. In this study, the final risk of each failure modes was prioritized by using the MATLAB fuzzy logic tool box with a combination of two assessments. The first assessment was concerned with the criteria which affected the actual probability of occurrence. This assessment considered the availability of the standard that was applied to prevent the likelihood of the scenario occurring. On the other hand, the second assessment was focused on evaluating the consequence of the failure by taking into account the availability of detection and the complexity of the failure rather than only the severity of the scenarios. A total of 87 failure scenarios were identified using failure modes and effect analysis （FMEA） procedures on hydrogen refueling station models. Fuzzy-based assessments were performed through risk prioritizing various failure scenarios with a fuzzy value （0 to 1） and risk level （low, medium, and high） while a tra- ditional risk assessment approach presented the risks only in forms of level （low, medium, and/or high）. Availability of the fuzzy value enabled further prioritizing on the risk results that fell in the same level of risk. This study concluded that fuzzy-based risk evaluation is able to further prioritize the decisions when compared with a traditional risk assessment method.     

流量可调燃气发生器压力闭环模糊控制算法

为了改进流量可调燃气发生器的调节精度,引入燃气发生器压力闭环控制,针对流量可调燃气发生器压力闭环控制特点,在压力闭环中引入了模糊积分控制,此控制算法响应速度快,超调量较小,不同工况及长时间工作下系统仍然有较好的动态特性。      

新型同步发电机数字励磁控制系统

介绍一种基于DSP芯片TMS320LF2407A,采用了参数自适应模糊PID励磁控制方式。实验证明运用这种控制方式比单纯用PID调节具有更好的动态性能,满足现代同步发电机在励磁控制方面的要求,并且在实际应用中表明有良好性能。     

基于聚类分析的证券业信息服务评价模型研究

随着金融业迅速发展,证券业信息服务扮演着越来越重要的角色。面对复杂多变的国内外经济环境及多种因素交互影响下的投资市场,有必要建立有效的证券业信息服务评价体系。基于信息服务质量理论分析和中国特点,建立了一套证券业信息服务评价体系;依据信息服务的有用性、易用性、有形性、安全性、及时性、回应性及多样性等关键指标,构建评价数学模型;采用因子分析聚类方法和SPSS软件,结合实例验证证券业信息服务评价体系。     

青岛市海岛旅游主体功能分区

考虑到海岛环境的特殊性、资源承载的有限性、空间开发功能的衍生性,从海岛旅游开发适宜性和海岛可持续保护的角度,与国家主体功能区规划和全国海岛保护与开发规划相衔接,构建海岛旅游功能分区评价指标体系,确定海岛旅游资源开发的适宜性评价因子及评价标准,并引入模糊多级综合评判理论,构建基于层次分析法的模糊综合评判模型。根据旅游资源开发适宜性综合评分结果以及海岛旅游开发的实际情况,合理确定不同区域海岛旅游开发功能的区划标准,以制定青岛市海岛旅游资源开发功能的区划方案。将青岛市海岛划分为旅游资源优先开发区、适度开发区、限制开发区、禁止开发区,根据区划方案进行海岛旅游开发功能空间定位和评价分析,为青岛市海岛旅游资源可持续开发利用提供理论和决策依据。     

Mining knowledge from natural language texts using fuzzy associated concept mapping

Natural Language Processing (NLP) techniques have been successfully used to automatically extract information from unstructured text through a detailed analysis of their content, often to satisfy particular information needs. In this paper, an automatic concept map construction technique, Fuzzy Association Concept Mapping (FACM), is proposed for the conversion of abstracted short texts into concept maps. The approach consists of a linguistic module and a recommendation module. The linguistic module is a text mining method that does not require the use to have any prior knowledge about using NLP techniques. It incorporates rule-based reasoning (RBR) and case based reasoning (CBR) for anaphoric resolution. It aims at extracting the propositions in text so as to construct a concept map automatically. The recommendation module is arrived at by adopting fuzzy set theories. It is an interactive process which provides suggestions of propositions for further human refinement of the automatically generated concept maps. The suggested propositions are relationships among the concepts which are not explicitly found in the paragraphs. This technique helps to stimulate individual reflection and generate new knowledge. Evaluation was carried out by using the Science Citation Index (SCI) abstract database and CNET News as test data, which are well known databases and the quality of the text is assured. Experimental results show that the automatically generated concept maps conform to the outputs generated manually by domain experts, since the degree of difference between them is proportionally small. The method provides users with the ability to convert scientific and short texts into a structured format which can be easily processed by computer. Moreover, it provides knowledge workers with extra time to re-think their written text and to view their knowledge from another angle.