粗糙集与模糊神经网络集成在故障诊断中的研究

考虑模糊聚类的数据离散功能,粗糙集理论对决策系统的约简能力,以及模糊神经网络在模式识别方面具有的优势,提出了粗糙集一自适应模糊神经网络推理系统（ANFIS）集成进行故障诊断的方案：首先,应用SOM方法离散故障诊断数据中的连续属性值;然后,基于粗糙集理论计算诊断决策系统的约简,按照实际需要确定诊断条件;最后,根据系统约简设计ANFIS进行故障诊断。4135柴油机的实际诊断结果验证了文中提出集成故障诊断方案的可行性。在数据充分的条件下,该方案可以推广应用于其它机械设备。     

固体火箭发动机故障诊断的神经网络方法研究

固体火箭发动机地面试验系统的故障诊断过程复杂,故障征兆和故障原因之间存在着许多不确定因素,精确定位故障存在许多困难.传统的神经网络方法和模糊推理方法为解决这一类故障诊断问题提出了一些算法,然而难以提高不确定故障诊断的性能.针对这种情况,提出了一种基于模糊神经网络的故障诊断方法.该算法同时具备了模糊理论的处理不确定、不准确信息的推理能力和神经网络的自学习能力.将这种方法应用到某固体火箭发动机地面试验系统的故障诊断,仿真结果表明,该算法有效,较好地解决了固体火箭发动机地面试验系统的不确定故障诊断问题.     

ANFIS模糊神经推理机在故障诊断中的应用

传统的故障诊断专家系统大多是基于知识的故障诊断系统，有一定的局限性。模糊神经网络技术的引入，给故障诊断专家系统带来了新的思路，将模糊理论与神经网络融合，利用神经网络来实现系统的模糊逻辑推理，建立了一种基于模糊系统（FS）与神经网络（NN）融合的系统故障诊断方法，并利用MATLAB中的ANFIS模糊工具来实现其模糊神经推理过程，通过对系统进行仿真，得到了比较满意的结果，实例表明，该工具用于故障诊断的模糊推理是高效可行的     

水电数字仿真在线融合故障诊断专家系统

为了解决丰满水电数字仿真系统的在线故障诊断问题，基于信息与方法融合的思想，提出了分布式集成神经网络建模方法、模糊神经网络专家系统(FNNES)在线故障诊断方法。将模糊神经网络(FNN)嵌入专家系统(ES)中，FNN负责知识获取和逻辑推理，ES负责系统信息的输入和输出、符号推理，并对FNN的结论进行解释。系统的运行验证了方法的有效性和实际应用价值。为现场诊断系统的开发提供了有益的方法和经验。     

基于知识和神经网络相结合的实时故障诊断专家系统

以钢厂冷轧生产线为对象，介绍如何将神经网络方法与传统的专家系统方法复合在一起，更好地解决故障诊断。具体介绍了系统的框架设计，神经网络的设计研究，并举例了说明了神经网络故障诊断的推理过程。     

电力变压器状态检测中复合推理方法的研究

本文在对电力系统的特点进行深入研究后,提出了基于分类框架推理技术、模糊推理技术、神经网络技术以及事例推理技术的复合推理方法,并将其应用于电力变压器状态检测.试用表明,复合推理方法比传统的单一推理方法具有更高的准确性和灵活性,并且可以在类似故障诊断领域中推广使用.     

故障诊断专家系统综合智能推理技术研究

推理机在故障诊断专家系统中起着非常重要的作用。提出普通规则、模糊逻辑和模糊神经网络推理相结合的综合智能推理机应用于故障诊断专家系统。综合智能推理机既能提高诊断推理的速度，又可以提高诊断推理的准确程度。通过对某型号导弹故障诊断验证，采用综合智能推理机诊断快速、准确率高，取得了较好的诊断效果。     

模糊神经网络在发动机故障诊断中应用研究

本文对模糊逻辑和神经网络故障诊断方法做了研究。根据这两种方法各自的优缺点,采用串联方法将二者相结合,用模糊信息处理方法对输八信号进行预处理,然后利用神经网络的逼近能力来实现对故障的诊断。将该方法构建的推理系统应用于汽油发动机偶发性疑难故障诊断。利用Matlab进行软件仿真,仿真结果表明该方法可以给出较高精度的诊断结果,与单纯使用模糊逻辑方法或神经网络方法都有较大改进,尤其列于单一系统的复杂故障具有很好的识别能力,有良好的应用前景。     

基于多级模糊神经网络的故障诊断在化工生产过程中的应用

化工生产过程一般都非常复杂，如柠檬酸蒸发。由于控制回路与测控参数很多，生产过程的故障检测与诊断问题非常困难，难以做到实时检查，得到其故障信息。所以本文提出一种基于神经网络的多级故障诊断系统。采用三级递阶模糊神经网络，降解整个系统故障诊断问题的复杂性，同时采用所有子神经网络全局并行的推理方式，具有快速处理能力，适合系统实时在线故障诊断。     

基于ANN与CBR相结合的复杂装备故障诊断研究

在分析了神经网络(ANN)方法与案例推理(CBR)方法的特点和互补性的基础上,设计了基于ANN与CBR相结合的复杂装备故障诊断模型.将人工神经网络方法融入CBR推理的故障库分类、案例检索、案例修改等多个阶段中,较好地解决了复杂电子装备故障诊断的快速与准确问题.最后通过对雷达情报综合电子信息系统故障实例的诊断仿真,验证了该算法的有效性.     

基于模糊神经网络的通用模型自适应控制

自适应控制是一种提高系统鲁棒性的有效方法。模糊神经网络具有了模糊逻辑和神经网络两者的优点,结合模糊神经网络（Fuzzy Neural Network—FNN）自适应控制策略和通用模型控制（Common Model Control—CMC）方法,以此来实现被控对象的逆控制,提出了基于模糊神经网络的通用模型自适应控制（FNNC—CMAC）。此控制方法参考轨迹是一条典型二阶曲线,仿真结果验证了鲁棒性,与基于模糊神经网络的通用模型控制及基于模糊逻辑的通用模型自适应控制相比,其控制性能更好。     

加热炉生产数据预处理策略研究

加热炉在钢铁企业发挥着非常重要的作用. 在加热炉中部分生产过程数据较难检测, 部分检测到的数据受到严重干扰和缺失, 这严重影响了加热炉的优化和控制, 而且还存在潜在的安全隐患. 本文针对加热炉这一复杂的过程, 设计了一个生产过程数据预处理系统. 该系统能对部分难以测量的数据用自适应模糊神经网络(FNN)方法进行预测, 能对过程数据进行滤波和正误判断, 能对异常数据进行剔除和替代, 并对过程数据替代值利用案例推理(CBR)方法建立完善机制. 该系统在某钢铁公司进行了实际应用, 取得了明显的应用效果.     

Intelligent forecasting system based on integration of electromagnetism-like mechanism and fuzzy neural network

Fuzzy neural network (FNN) architectures, in which fuzzy logic and artificial neural networks are integrated, have been proposed by many researchers. In addition to developing the architecture for the FNN models, evolution of the learning algorithms for the connection weights is also a very important. Researchers have proposed gradient descent methods such as the back propagation algorithm and evolution methods such as genetic algorithms (GA) for training FNN connection weights. In this paper, we integrate a new meta-heuristic algorithm, the electromagnetism-like mechanism (EM), into the FNN training process. The EM algorithm utilizes an attraction–repulsion mechanism to move the sample points towards the optimum. However, due to the characteristics of the repulsion mechanism, the EM algorithm does not settle easily into the local optimum. We use EM to develop an EM-based FNN (the EM-initialized FNN) model with fuzzy connection weights. Further, the EM-initialized FNN model is used to train fuzzy if–then rules for learning expert knowledge. The results of comparisons done of the performance of our EM-initialized FNN model to conventional FNN models and GA-initialized FNN models proposed by other researchers indicate that the performance of our EM-initialized FNN model is better than that of the other FNN models. In addition, our use of a fuzzy ranking method to eliminate redundant fuzzy connection weights in our FNN architecture results in improved performance over other FNN models.     

Direct adaptive fuzzy-neural control with state observer andsupervisory controller for unknown nonlinear dynamical systems

In this paper, an observer-based direct adaptive fuzzy-neural network (FNN) controller with supervisory mode for a certain class of high order unknown nonlinear dynamical system is presented. The direct adaptive control (DAC) has the advantage of less design effort by not using FNN to model the plant. By using an observer-based output feedback control law and adaptive law, the free parameters of the adaptive FNN controller can be tuned on-line based on the Lyapunov synthesis approach. A supervisory controller is appended into the FNN controller to force the state to be within the constraint set. Therefore, if the FNN controller cannot maintain the stability, the supervisory controller starts working to guarantee stability. On the other hand, if the FNN controller works well, the supervisory controller will be de-activated. The overall adaptive scheme guarantees the global stability of the resulting closed-loop system in the sense that all signals involved are uniformly bounded. Simulation results also show that our initial control effort is much less than those in previous works, while preserving the tracking performance     

A Recurrent Self-Evolving Interval Type-2 Fuzzy Neural Network for Dynamic System Processing

This paper proposes a recurrent self-evolving interval type-2 fuzzy neural network (RSEIT2FNN) for dynamic system processing. An RSEIT2FNN incorporates type-2 fuzzy sets in a recurrent neural fuzzy system in order to increase the noise resistance of a system. The antecedent parts in each recurrent fuzzy rule in the RSEIT2FNN are interval type-2 fuzzy sets, and the consequent part is of the Takagi-Sugeno-Kang (TSK) type with interval weights. The antecedent part of RSEIT2FNN forms a local internal feedback loop by feeding the rule firing strength of each rule back to itself. The TSK-type consequent part is a linear model of exogenous inputs. The RSEIT2FNN initially contains no rules; all rules are learned online via structure and parameter learning. The structure learning uses online type-2 fuzzy clustering. For the parameter learning, the consequent part parameters are tuned by a rule-ordered Kalman filter algorithm to improve learning performance. The antecedent type-2 fuzzy sets and internal feedback loop weights are learned by a gradient descent algorithm. The RSEIT2FNN is applied to simulations of dynamic system identifications and chaotic signal prediction under both noise-free and noisy conditions. Comparisons with type-1 recurrent fuzzy neural networks validate the performance of the RSEIT2FNN.     

Case-Based Reasoning System and Artificial Neural Networks: A Review

In this survey paper, the-state-of-art of the connectionist model (i.e. Artificial Neural Network (ANN)) based methodology for a Case-Based Reasoning (CBR) system design is discussed. Special emphasis is laid on how the ANN can advance CBR technology by building an ANN-based CBR system, or integrating itself as a component within a CBR system. Several ANN models proposed for constructing a CBR system and for solving some special issues involved in a CBR process are described. The main characteristics of each model are analysed, and the advantages and limitations of different models are compared. Also, future research directions are outlined.     

基于模糊神经网络的机器人滑模自适应控制

滑模控制（SMC）响应快，对系统参数和外部扰动呈不变性，可保证系统的渐近稳定性，但其缺点是控制存在很强的抖动；而模糊神经网络（FNN）具有模糊系统和神经网络共同的特点。将滑模控制和模糊神经网络控制有机结合，利用简单得到的学习信号对模糊神经网络进行在线学习，通过平滑切换函数实现直接自适应控制策略。对两连杆机械手的仿真研究表明，在存在模型误差和外部扰动的情况下，该方案既能达到高精度快速跟踪的目的，又能有效减小滑模控制的抖动问题。     

多传感器技术在污水分析中的应用研究

实现污水分析的自动化和分析结果的准确性是污水处理厂的重要任务,模糊神经网络技术的迅速发展及其理论的不断完善为其在此领域的应用奠定了基础,通过实践证明:该理论用于污水分析系统是可行的。传统的污水自动分析系统中存在许多问题,多传感器技术的应用,使这些问题得到了解决。利用模糊神经网络技术对多传感器系统进行模型的建立,并将该模型应用到实际的污水分析系统中,与传统的系统及方法进行比较,得到了良好的实验效果。     

A supervisory fuzzy neural network control system for trackingperiodic inputs

A supervisory fuzzy neural network (FNN) control system is designed to track periodic reference inputs in this study. The control system is composed of a permanent magnet (PM) synchronous servo motor drive with a supervisory FNN position controller. The supervisory FNN controller comprises a supervisory controller, which is designed to stabilize the system states around a defined bound region and an FNN sliding-mode controller, which combines the advantages of the sliding-mode control with robust characteristics and the FNN with online learning ability. The theoretical and stability analyses of the supervisory FNN controller are discussed in detail. Simulation and experimental results show that the proposed control system is robust with regard to plant parameter variations and external load disturbance. Moreover, the advantages of the proposed control system are indicated in comparison with the sliding-mode control system     

A fuzzy neural network model for predicting clothing thermal comfort

This paper presents a Fuzzy Neural Network (FNN) based local to overall thermal sensation model for prediction of clothing thermal function in functional textile design system. Unlike previous experimental and regression analysis approaches, this model depends on direct factors of human thermal response — body core and skin temperatures. First the local sensation is predicted by a FNN network using local body part skin temperatures, their change rates, and core temperature as inputs; then the overall sensation is predicted. This is also performed by a FNN network. The FNN networks are developed on the basis of the Feed-Forward Back-Propagation (FFBP) network; the advantage of using fuzzy logic here is to reduce the requirement of training data. The simulation result shows a good correlation between predicted and the traditional experimental data.