Fault diagnosis of turbine based on fuzzy cross entropy of vague sets

The fuzzy cross entropy of vague sets, so-called vague cross entropy, is introduced by analogy with the cross entropy of probability distributions. And then a new method of the fault diagnosis is proposed on the basis of the vague cross entropy and is applied to the fault diagnosis of turbine. The vague cross entropy between a testing sample and the knowledge of system faults is evaluated in the fault diagnosis of the turbine vibration. If the cross-entropy value is small, the testing sample is near to a type of fault knowledge. Then, the type of vibration fault is determined according to the minimum cross-entropy value. The fault-diagnosis example of the turbine demonstrates that the proposed method cannot only diagnose the main fault types of the turbine, it can also detect useful information for future trends and multi-fault analysis.     

Vague关系与Vague映射

在系统研究了作为Zadeh模糊集理论重要扩展的Vague关系及其合成运算,并就Vague关系的性质进行了讨论。在此基础上研究了Vague等价关系,给出了Vague映射的概念,讨论了Vague映射的一些性质。     

Vague划分

根据vague集具有真假隶属度的特点,首先提出了基于t-模和t-余模的真相容度、假相容度、真相等度和假相等度的概念.然后合理地利用真相容度、假相容度、真相等度和假相等度提出了半vague划分和vague划分的概念.并讨论了它们的性质.     

基于Vague集的含洞不规则Vague区域关系

模糊区域的空间信息表示和区域关系处理在空间数据库、地理信息系统和人工智能等领域具有重要的意义.引入Vague集的概念和理论对含洞不规则Vague区域关系进行了系统的研究.基于Vague集给出了Vague区域、Vague洞和原子域等概念;将含洞不规则Vague区域分成原子域,研究了原子域间的空间关系;联合原子域关系,给出了含洞不规则Vague区域关系.研究成果可较好地处理含洞不规则Vague区域内的模糊点不确定的隶属信息和复杂的含洞不规则Vague区域的空间关系的表示和分析等问题.     

基于未知度的Vague集相似度量方法研究

分析并指出了现有的相似度量方法的不足,考虑了未知度在相似度量方法中的影响,提出了一种基于未知度Vague集相似度量的方法,通过实例说明该方法具有一定的有效性和优越性。     

"关于Vague集的模糊熵及其构造"的注记

讨论了文[1，2]中将vague集变换为fuzzy集的转换函数的作用，指出了vague集就是一类特殊的L-模糊集，分析了文[1，2]中提出的vague集的模糊熵概念的不足，在此基础上，基于对不确定性信息处理的背景，提出了一种模糊正熵和模糊负熵的概念，并讨论了它们的性质。     

基于Vague熵的Vague集相似度量

对当前Vague集相似度量及Vague熵之间的关系进行了分析,指出它们并不匹配,本文分析了Vague熵的影响因素,给出一种新的Vague熵定义及一种新的计算公式,提出基于熵的Vague集新相似度量,与现有方法相比,本文的方法可以像普通模糊集一样,一个Vague集的熵可由它与它的补集间的相似度量较好地刻画.     

Improved method of multicriteria fuzzy decision-making based on vague sets

An improved method is presented, which provides improved score functions to measure the degree of suitability of each of a set of alternatives, with respect to a set of criteria presented with vague values. The improved algorithm for score functions is introduced by taking into account the effect of an unknown degree (hesitancy degree) of the vague values on the degree of suitability to which each alternative satisfies the decision-maker’s requirement. The meaning of the proposed function is more transparent than that of other existing functions, which are not reasonable in some cases. The proposed function illustrates that it has stronger discrimination in comparison with previous functions. The applicability of this improved multicriteria fuzzy decision-making approach is also demonstrated by means of examples. The improved method can be used to rank the decision alternatives according to the decision criteria. The functions proposed in this paper can provide a more useful technique than previous functions, in order to efficiently help the decision-maker.     

基于Vague关系数据模型的除操作研究

基于Vague集理论的Vague关系数据库由于其所含信息的模糊性,对应于现实世界的多种状态。为此,基于扩展的Vague关系数据模型,研究一种条件受限的Vague除操作实现方法,并给出相应的操作步骤和算法。实例分析结果表明,该实现方法可直接作用于整个Vague关系数据库,无需对Vague关系数据库对应的所有状态逐一进行扫描即可获得正确的操作结果,具有较高的执行效率。     

P2P网络环境下的基于Vague集的抗攻击信任模型

由于P2P网络的信任机制经常受到恶意节点的欺骗和攻击,提出一种基于Vague集的抗攻击信任模型,用隶属度度量具有不确定信息的信任度,引入时间敏感系数和惩罚系数,处理资源提供者的直接反馈信息,用Vague集相似度量评价推荐节点的回馈信息,并给出该信任模型的实现方案和仿真实验.实验结果表明该信任模型能够抵御各类欺骗和攻击行为.