模糊神经网络在高强混凝土强度预测与配合比设计中的应用

针对模糊系统中规则结论为数值和线性函数的两种表示方式,找了它们的共同点,将它们置于同一网络结构中,形成规则结论为数值和线性函数（T－S模型）的两种模糊神经网络（Fuzzy Neural Networks,简称FNN）,导出了它们的网络模型及其学习算法。并首次将其应用于高强混凝土强度预测和配合比设计中。文章还介绍了一种简单有效地从样本数据中提取模糊规则及确定FNN参数初值的方法。运算结果表明,FNN不仅具有很高的预测精度,而且网络的结点和权值均具有明确的物理意义,可以借此深入分析高强混凝土综合性能与影响它们的因素之间的非线性关系。     

基于结合自适应步长布谷鸟搜查算法的模糊神经网络的软件可靠性增长模型

针对现有的软件可靠性增长模型(SRGM)适用性较差、预测精度波动大的问题,使用自适应步长布谷鸟搜查(ASCS)算法对模糊神经网络（FNN）的权重和阈值进行寻优,利用得到了最优权重和阈值的FNN建立SRGM。在使用缺陷数据对FNN训练的过程中,利用ASCS来调整FNN的权重和阈值,以此提高在预测过程中的精度,同时采用多次预测结果取均值的方式来减小FNN预测的波动性,以此建立基于结合自适应步长布谷鸟搜查算法的模糊神经网络（ASCS-FNN）的软件可靠性增长模型。利用3组软件缺陷数据,以误差比均值和误差平方和作为衡量标准,对基于ASCS-FNN、结合模拟退火算法的动态模糊神经网络（SA-DFNN）、FNN、BP网络（BPN）建立的SRGM的一步向前预测能力进行比较。预测结果表明,在四组模型中,基于ASCS-FNN建立的SRGM相对于SA-DFNN、FNN、BPN建立的SRGM的平均预测精度相对提高率RI(AE)和RI(SSE)分别为-1.48%、54.8%、33.8%和14.4%、76%、35.9%,并且该模型比FNN、BPN建立的SRGM在相同缺陷数据下的预测波动性小,而且网络结构比SA-DFNN的网络结构简单。因此该模型具有预测精度较高、预测稳定和具有一定的适用性等优点。     

基于粗糙集理论的多属性评估方法的研究

传统的模糊综合评价利用模糊数学理论来描述评价过程中涉及的一些模糊因素,取得了一定效果。但这种方法存在如隶属度参数的调整的主观性,网络结构不易确定,模糊规则的选取等问题不易解决。文章提出结合粗糙集理论（RS）和模糊神经网络（FNN）的一种网络评估模型,使得网络的结构容易确定,并利用Rosetta软件轻松提取模糊规则,是一种具有通用性的网络评估模型。     

应用模糊神经网络预测油田产量

为了研究受多变量、时变和不确定因素影响的油田产量预测问题,将模糊逻辑推理技术与人工神经网络相结合,构建具有模糊逻辑推理和学习功能的模糊神经网络(FNN)系统。该系统基于现有的油田开发历史数据,建立相应的规则集,使用神经网络的训练方法(如梯度下降学习算法),在训练过程中调整参数,并自适应增加规则,以使系统的输出最佳地逼近于目标样本。通过对某油田的实际开发历史数据的拟合与测试,结果表明该模糊神经网络能够较精确地预测未来的油产量,与常规的BP神经网络相比,其预测精度更高、训练速度更快。因此,基于模糊神经网络(FNN)的油田产量预测方法研究具有较好的实际应用价值。     

基于T-S模糊模型的非线性预测控制策略

提出了一种新的基于T-S模糊模型的非线性预测控制策略. T-S模糊模型用于描述对象的非线性动态特性, 通过将模糊模型的输出反馈回来作为模型输入, 从而构成了模糊多步预报器. 由于T-S模糊模型每条规则的结论部分是一个线性模型, 因此整个模糊模型可以看作一个线性时变系统, 从而将模糊预测控制器中的非线性优化问题转化为一个线性二次寻优问题, 以方便求解. pH中和过程的仿真结果表明其性能优于传统的动态矩阵控制器.     

基于改进PSO与规则约简的模糊系统优化算法

模糊系统是一种具有强可解释性和高鲁棒性的智能方法,但目前仍存在精度不高、产生的模糊规则太多等缺陷.针对目前存在的问题,论文通过改进粒子群优化算法优化模糊系统高斯型隶属度函数的参数,以及计算规则支持度约简模糊规则,提出了CPSFS和SPSFS两种模糊系统优化算法.在两个不同领域的经典数据集上的研究结果表明:1)CPSFS算法在训练集和测试集上的预测精度明显优于传统的BP神经网络、RBF神经网络、线性回归等算法;2)CPSFS算法与SPSFS算法减少了大量模糊规则,保证了模型的可解释性;3)CPSFS算法在约简模糊规则后预测精度依然表现最优,符合新时代下回归问题对于AI技术的要求.     

模糊神经网络在电力短期负荷预测中的应用

提出用于电力短期负荷预测(SILF)的一种模糊神经网络(FNN)方法，该方法针对BP网络收敛速度慢、易导致局部极小值的缺点，将考虑气候、温度、星期类型等影响因素的模糊技术与快速二阶BP网络相结合，并以南方电网负荷预测为例，应用MATLAB蚀语言对系统进行仿真训练，测试结果表明，该方法具有较高的预测精度。     

基于具有加权模糊隶属函数的神经网络的混沌时间序列预测

本文提出了以时间延迟坐标嵌入方法为基础的周期性波动预测模型。此模型使用一种叫作具有加权模糊隶属函数的神经网络的神经模糊网络(NEWFM)。在主要综合指标的预处理时间序列中使用了时间延迟坐标嵌入方法,并将此序列用作此神经模糊网络的输入数据来预测商业周期。以小波变换为基础使用其他方法进行了对比性研究,并对性能比较进行了主成分分析。使用线性回归分析来测试预测结果,以比较输入数据与目标类别,国内生产总值的近似值。另外两个模型忽略了基于混沌的模型捕捉非线性动态模型和系统中的相互作用。检验结果表明基于混沌的方法能够有效地增强预测能力,因此表明此方法比其他方法具有更优越的性能。     

一种训练FNN的新方法

众所周知,训练FNN(Feed-forward Neural Network)的方法显然很多,但是至今未能彻底解决"收敛不迅速"和"收敛不稳健"这两大难题,从而影响了FNN的应用。针对此问题,此文提出了一种训练FNN的新方法,该方法巧妙地将BP-NN(Back Propagation-Neural Network)基本算法和分层优化算法融合为一体,把每层权重视为独立训练过程,精心构建了基于非线性泰勒级数描述的FNN目标函数,不仅能将优化每层权重问题简化为线性问题,而且还可有效控制线性误差。文中还提供了一种训练FNN的稳健快速的迭代算法,实验结果表明,该方法优于其它任何方法。     

一种神经模糊系统模型

本文提出一种神经模糊系统模型,其中模糊规则前件用π隶属函数(形状类似于三角形隶属函数,但具有平滑性)表达,给出了类似于BP的参数学习算法.对于平滑函数近似问题的仿真结果表明,与模糊规则前件使用三角形隶属函数的神经模糊系统模型相比,本文提出的模型具有学习过程更加稳定平滑和逼近误差小的优点.对这两种模型性能上的差异做了定性解释.     

混凝土强度模糊神经网络检测系统

为了提高检测精度,建立了模糊神经网络来综合评定结构的混凝土强度,充分利用了钻芯法和回弹法这两种常用混凝土测强方法的特点以及模糊神经网络的自学习、泛化和模糊逻辑推理功能.根据回弹值与钻芯值之间趋于幂函数关系的专家经验,将回弹值和钻芯值分别取常用对数作为模型的输入和输出,以提高建模精度.同时,模型参数采用一种混合学习算法确定,可以提高学习速度.实验结果表明,模型预测结果的平均相对误差为10.316%,相对标准差为12.895%,满足工程实际要求.该方法可以有效地映射出钻芯、回弹数据间复杂的非线性关系,为混凝土强度检测评定提供了一种有效的途径.     

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.     

Fuzzy polynomial neural networks for approximation of the compressive strength of concrete

The main purpose of this paper is to develop fuzzy polynomial neural networks (FPNN) to predict the compressive strength of concrete. Two different architectures of FPNN are addressed (Type1 and Type2) and their training methods are discussed. In this research, the proposed FPNN is a combination of fuzzy neural networks (FNNs) and polynomial neural networks (PNNs). Here, while the FNN demonstrates the premises (If-Part) of the fuzzy model, the PNN is implemented as its consequence (Then-Part). To enhance the performance of the network, back propagation (BP), and list square error (LSE) algorithms are utilized for the tuning of the system.Six different FPNN architectures are constructed, trained, and tested using the experimental data of 458 different concrete mix-designs collected from three distinct sources. The data are organized in a format of six input parameters of concrete ingredients and one output as 28-day compressive strength of the mix-design. Using root means square (RMS) and correlation factors (CFs), the models are evaluated and compared with training and testing data pairs. The results show that FPNN-Type1 has strong potential as a feasible tool for prediction of the compressive strength of concrete mix-design. However, the FPNN-Type2 is recognized as unfeasible model to this purpose.     

基于BOA-ELM的混凝土抗压强度预测研究

为控制控制混凝土生产成本,在混凝土拌和期限制抗压强度不足的缺陷构建产出,可以有效降低原料的浪费,是节能降耗的关键方法之一。针对混凝土抗压强度的传统测量方法严重滞后的问题,提出了基于贝叶斯优化极限学习机(BOA-ELM)的混凝土抗压强度预测方法。首先,分析了混凝土拌和过程中对抗压强度预测值实时获得的需求。以各物料的用量为分析基础,28天标准养护后混凝土抗压强度值为预测目标,设计了基于极限学习机的强度预测模型。其次,为进一步提高模型的稳定性以及准确行,提出基于贝叶斯优化的极限学习机模型,根据模型超参数的分布特征,以高斯过程作为超参的先验分布,预测误差最小化作为目标,寻找最优的模型超参。最后,在实际施工产生的C50标号混凝土数据集上测试文中模型,并对比分析了其他预测模型和寻优算法。结果表明,结合了贝叶斯优化的极限学习机预测模型相较于经典算法具有更高的预测准确性和模型训练的高效性。     

高性能混凝土强度预测的神经网络-主成分分析

在误差逆传播算法神经网络预测模型数据前处理中,对样本集优化,采用多元统计分析中的主成分分析法,提取影响粉煤灰高性能混凝土抗压强度的主要因素,消除影响因素间的线性相关性。研究结果表明,用该方法处理后的样本数据输入神经网络,提高了预测效率,训练时间减少,预测精度也有一定程度的提高,网络结构得到简化。     

Tuning certainty factor and local weight of fuzzy production rulesby using fuzzy neural network

Approximate reasoning in a fuzzy system is concerned with inferring an approximate conclusion from fuzzy and vague inputs. There are many ways in which different forms of conclusions can be drawn. Fuzzy sets are usually represented by fuzzy membership functions. These membership functions are assumed to have a clearly defined base. For other fuzzy sets such as intelligent, smart, or beautiful, etc., it would be difficult to define clearly its base because its base may consist of several other fuzzy sets or unclear nonfuzzy bases. A method to handle this kind of fuzzy set is proposed. A fuzzy neural network (FNN) is also proposed to tune knowledge representation parameters (KRPs). The contributions are that we are able to handle a broader range of fuzzy sets and build more powerful fuzzy systems so that the conclusions drawn are more meaningful, reliable, and accurate. An experiment is presented to demonstrate how our method works.     

Adaptive hybrid intelligent control for uncertain nonlinear dynamical systems

A new hybrid direct/indirect adaptive fuzzy neural network (FNN) controller with a state observer and supervisory controller for a class of uncertain nonlinear dynamic systems is developed in this paper. The hybrid adaptive FNN controller, the free parameters of which can be tuned on-line by an observer-based output feedback control law and adaptive law, is a combination of direct and indirect adaptive FNN controllers. A weighting factor, which can be adjusted by the tradeoff between plant knowledge and control knowledge, is adopted to sum together the control efforts from indirect adaptive FNN controller and direct adaptive FNN controller. Furthermore, 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 deactivated. The overall adaptive scheme guarantees the global stability of the resulting closed-loop system in the sense that all signals involved are uniformly bounded. Two nonlinear systems, namely, inverted pendulum system and Chua's (1989) chaotic circuit, are fully illustrated to track sinusoidal signals. The resulting hybrid direct/indirect FNN control systems show better performances, i.e., tracking error and control effort can be made smaller and it is more flexible during the design process.     

Adaptive Fuzzy Neural Networks as identifiers of discrete-time nonlinear dynamic systems

An adaptive supervised learning scheme is proposed in this paper for training Fuzzy Neural Networks (FNN) to identify discrete-time nonlinear dynamical systems. The FNN constructs are neural-network-based connectionist models consisting of several layers that are used to implement the functions of a fuzzy logic system. The fuzzy rule base considered here consists of Takagi-Sugeno IF-THEN rules, where the rule outputs are realized as linear polynomials of the input components. The FNN connectionist model is functionally partitioned into three separate parts, namely, the premise part, which provides the truth values of the rule preconditional statements, the consequent part providing the rule outputs, and the defuzzification part computing the final output of the FNN construct. The proposed learning scheme is a two-stage training algorithm that performs both structure and parameter learning, simultaneously. First, the structure learning task determines the proper fuzzy input partitions and the respective precondition matching, and is carried out by means of the rule base adaptation mechanism. The rule base adaptation mechanism is a self-organizing procedure which progressively generates the proper fuzzy rule base, during training, according to the operating conditions. Having completed the structure learning stage, the parameter learning is applied using the back-propagation algorithm, with the objective to adjust the premise/consequent parameters of the FNN so that the desired input/output representation is captured to an acceptable degree of accuracy. The structure/parameter training algorithm exhibits good learning and generalization capabilities as demonstrated via a series of simulation studies. Comparisons with conventional multilayer neural networks indicate the effectiveness of the proposed scheme.     

水泥混凝土强度试验数据的电子标识技术应用

提出了一种新的水泥混凝土强度试验数据的获取流程,将数据的获取分为工程信息的获取和混凝土强度试验数据的获取两部分,两部分数据以RFID(射频标识)卡编号的唯一性来标识和关联,并在此基础上研究了系统基于RFID技术的信息传递模型.在信息传递的实现研究方面,研究设计了混凝土试块RFID芯片信息智能管理系统软件,并设计了水泥混凝土试验数据的获取装置.实际的工程应用验证了电子标识技术在水泥混凝土强度试验数据标识应用中的可行性和有效性.     

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.