Prediction of NO_(x)concentration using modular long short-term memory neural network for municipal solid waste incineration

Air pollution control poses a major problem in the implementation of municipal solid waste incineration(MSWI).Accurate prediction of nitrogen oxides(NO_(x))concentration plays an important role in efficient NO_(x)emission controlling.In this study,a modular long short-term memory(M-LSTM)network is developed to design an efficient prediction model for NO_(x)concentration.First,the fuzzy C means(FCM)algorithm is utilized to divide the task into several sub-tasks,aiming to realize the divide-and-conquer ability for complex task.Second,long short-term memory(LSTM)neural networks are applied to tackle corresponding sub-tasks,which can improve the prediction accuracy of the sub-networks.Third,a cooperative decision strategy is designed to guarantee the generalization performance during the testing or application stage.Finally,after being evaluated by a benchmark simulation,the proposed method is applied to a real MSWI process.And the experimental results demonstrate the considerable prediction ability of the M-LSTM network.

Inverse stochastic resonance in modular neural network with synaptic plasticity

This work explores the inverse stochastic resonance(ISR) induced by bounded noise and the multiple inverse stochastic resonance induced by time delay by constructing a modular neural network, where the modified Oja’s synaptic learning rule is employed to characterize synaptic plasticity in this network. Meanwhile, the effects of synaptic plasticity on the ISR dynamics are investigated. Through numerical simulations, it is found that the mean firing rate curve under the influence of bounded noise has an inverted bell-like shape, which implies the appearance of ISR. Moreover, synaptic plasticity with smaller learning rate strengthens this ISR phenomenon, while synaptic plasticity with larger learning rate weakens or even destroys it. On the other hand, the mean firing rate curve under the influence of time delay is found to exhibit a decaying oscillatory process, which represents the emergence of multiple ISR. However, the multiple ISR phenomenon gradually weakens until it disappears with increasing noise amplitude. On the same time, synaptic plasticity with smaller learning rate also weakens this multiple ISR phenomenon, while synaptic plasticity with larger learning rate strengthens it. Furthermore, we find that changes of synaptic learning rate can induce the emergence of ISR phenomenon. We hope these obtained results would provide new insights into the study of ISR in neuroscience.

A Short-Term Climate Prediction Model Based on a Modular Fuzzy Neural Network

In terms of the modular fuzzy neural network (MFNN) combining fuzzy c-mean (FCM) cluster and single-layer neural network, a short-term climate prediction model is developed. It is found from modeling results that the MFNN model for short-term climate prediction has advantages of simple structure, no hidden layer and stable network parameters because of the assembling of sound functions of the self-adaptive learning, association and fuzzy information processing of fuzzy mathematics and neural network methods. The case computational results of Guangxi flood season (JJA) rainfall show that the mean absolute error (MAE) and mean relative error (MRE) of the prediction during 1998-2002 are 68.8 mm and 9.78%, and in comparison with the regression method, under the conditions of the same predictors and period they are 97.8 mm and 12.28% respectively. Furthermore, it is also found from the stability analysis of the modular model that the change of the prediction results of independent samples with training times in the stably convergent interval of the model is less than 1.3 mm. The obvious oscillation phenomenon of prediction results with training times, such as in the common back-propagation neural network (BPNN) model, does not occur, indicating a better practical application potential of the MFNN model.

MNN-XSS:Modular Neural Network Based Approach for XSS Attack Detection

The rapid growth and uptake of network-based communication technologies have made cybersecurity a significant challenge as the number of cyber-attacks is also increasing.A number of detection systems are used in an attempt to detect known attacks using signatures in network traffic.In recent years,researchers have used different machine learning methods to detect network attacks without relying on those signatures.The methods generally have a high false-positive rate which is not adequate for an industry-ready intrusion detection product.In this study,we propose and implement a new method that relies on a modular deep neural network for reducing the false positive rate in the XSS attack detection system.Experiments were performed using a dataset consists of 1000 malicious and 10000 benign sample.The model uses 50 features selected by using Pearson correlation method and will be used in the detection and preventions of XSS attacks.The results obtained from the experiments depict improvement in the detection accuracy as high as 99.96%compared to other approaches.

Aeromagnetic Compensation Algorithm Based on Levenberg-Marquard Neural Network

The magnetic compensation of aeromagnetic survey is an important calibration work,which has a great impact on the accuracy of measurement.In an aeromagnetic survey flight,measurement data consists of diurnal variation,aircraft maneuver interference field,and geomagnetic field.In this paper,appropriate physical features and the modular feedforward neural network(MFNN)with Levenberg-Marquard(LM)back propagation algorithm are adopted to supervised learn fluctuation of measuring signals and separate the interference magnetic field from the measurement data.LM algorithm is a kind of least square estimation algorithm of nonlinear parameters.It iteratively calculates the jacobian matrix of error performance and the adjustment value of gradient with the regularization method.LM algorithm’s computing efficiency is high and fitting error is very low.The fitting performance and the compensation accuracy of LM-MFNN algorithm are proved to be much better than those of TOLLES-LAWSON(T-L)model with the linear least square(LS)solution by fitting experiments with five different aeromagnetic surveys’data.

基于短时傅里叶变换和深度网络的模块化多电平换流器子模块IGBT开路故障诊断

针对现有模块化多电平换流器(MMC)子模块故障诊断过程中所需传感器较多、测量干扰较大等问题,提出一种基于深度学习的MMC子模块IGBT开路故障诊断方法。在对MMC子模块开路故障特征进行分析的基础上,利用短时傅里叶变换(STFT)提取桥臂电压信号的谐波分量信息作为故障诊断所需的特征参数。将所得到的特征参数进行处理后构建故障诊断样本,在通过深度置信网络实现故障类型快速检测的基础上,依据不同故障类型,构建多个基于卷积神经网络的故障定位网络,进而实现开路故障的检测与定位。通过129电平的MMC系统仿真模型和降功率的MMC实验系统搭建,对该文所提方法进行了验证。仿真和实验结果表明,所提故障诊断方法可以在减少传感器数量的基础上实现子模块开路故障的诊断,提高系统的可靠性。

基于注意力模块化神经网络的城市固废焚烧过程氮氧化物排放预测

氮氧化物(nitrogen oxides,NO_(x))浓度的实时精准检测是实现脱硝过程闭环控制的前提,对提高城市固废焚烧(municipal solid waste incineration,MSWI)过程脱硝效率具有重要意义。为此,提出了一种基于注意力模块化神经网络(attention modular neural network,AMNN)的MSWI过程NO_(x)排放预测方法。首先,模拟脑网络“分而治之”处理复杂任务的特性,利用模糊C均值(fuzzy C-means,FCM)聚类算法将待预测任务划分为多个子任务,从而降低预测任务复杂度;其次,针对各子任务,设计一种自组织模糊神经网络(self-organizing fuzzy neural network,SOFNN)构建子模型,通过神经元增删机制和二阶学习算法提高子模型的学习效率和学习精度;然后,提出了一种基于注意力机制的子模型整合策略,进一步提高预测模型的泛化性能;最后,通过基准实验Mackey-Glass时间序列预测和北京某MSWI厂实际数据验证了AMNN的可行性和有效性。

基于模糊Modular神经网络的官厅水库及邻区的地震危险性估计

首先介绍了模糊Modular神经网络的原理、建模方法与仿真实验,然后利用该方法把一些常用的地震学指标作为神经网络的输入,未来50年最大震级则作为网络的期望输出,对官厅水库及邻区的地震活动进行学习与最大震级序列建模,进行危险性预测。通过分析,认为该方法在一定程度上具有学习、建模与外推预测泛化能力,具有很好的中长期地震危险性预测效果,可以作为中长期地震危险性分析的工具。

改进的模糊Modular神经网络在既有建筑可靠性鉴定中的应用

在Takagi-Sugeno模糊逻辑系统的基础上,提出了改进的模糊Modular神经网络模型(IF-MNN),并将该模型应用于既有建筑的可靠性鉴定。改进的模型是将传统的模糊Modular神经网络模型中的单输出改进为多输出。这种改进的多输入多输出的模糊Modular神经网络模型具有预测性能好、训练学习速度快的优点,它的系统门网络采用模糊C均值聚类算法代替K-means算法,专家网络的训练中引进了先进的Levenberg-Marquardt算法。在应用改进的模糊Modular神经网络模型对既有建筑进行可靠性鉴定的过程中,综合考虑了各主要因素对既有建筑可靠性鉴定等级的影响,并将经量化处理的影响因素作为网络的外部输入,将网络计算得到的4个输出值分别作为样本对应于不同可靠性等级的隶属度,建筑可靠性鉴定的最终评判等级为最大隶属度所对应的等级。训练和预测样本的计算结果证明了改进的模糊Modular神经网络模型在既有建筑可靠性鉴定中应用的可行性和有效性。

一种模糊Modular神经网络模型及其应用

将神经网络模糊系统与模糊C均值聚类法相结合 ,对模糊Modular神经网络进行研究 ,提出了该模糊神经网络模型的多输出结构及其学习算法 ,据此开发了模糊神经网络诊断系统 ,并将其用于某电源分系统的诊断分析 ,运行的结果表明 。

Synchronization transition of a modular neural network containing subnetworks of different scales

Time delay and coupling strength are important factors that affect the synchronization of neural networks.In this study,a modular neural network containing subnetworks of different scales was constructed using the Hodgkin–Huxley(HH)neural model;i.e.,a small-scale random network was unidirectionally connected to a large-scale small-world network through chemical synapses.Time delays were found to induce multiple synchronization transitions in the network.An increase in coupling strength also promoted synchronization of the network when the time delay was an integer multiple of the firing period of a single neuron.Considering that time delays at different locations in a modular network may have different effects,we explored the influence of time delays within each subnetwork and between two subnetworks on the synchronization of modular networks.We found that when the subnetworks were well synchronized internally,an increase in the time delay within both subnetworks induced multiple synchronization transitions of their own.In addition,the synchronization state of the small-scale network affected the synchronization of the large-scale network.It was surprising to find that an increase in the time delay between the two subnetworks caused the synchronization factor of the modular network to vary periodically,but it had essentially no effect on the synchronization within the receiving subnetwork.By analyzing the phase difference between the two subnetworks,we found that the mechanism of the periodic variation of the synchronization factor of the modular network was the periodic variation of the phase difference.Finally,the generality of the results was demonstrated by investigating modular networks at different scales.

注意力改进的动态自组织模块化神经网络结构设计及应用

针对混沌时间序列的复杂性和非线性特点,提出了一种专注于此类挑战的新型神经网络模型,即注意力改进的动态自组织模块化神经网络模型(ADAMNN)。该模型基于分而治之的思想,通过注意力机制计算不同子网络与输入数据的相似度,并利用层次聚类自适应地划分子网络。随后,采用基于层次聚类的动态生长机制,对子网络簇进行增减,最后通过激活的子网络簇对输入样本进行在线学习;同时,结合传统的集成输出方法,提出了一种基于注意力机制的子网络加权集成输出方法。最终分别在Mackey-Glass时间序列、M-G快时变时间序列、非线性系统辨识、煤矿开采过程中在瓦斯浓度数据集上进行了实验,ADAMNN展现出了实时更新子网络中心、动态构建子网络簇的能力,而且与基于欧几里得空间的动态自适应模块化神经网络相比,预测准确度提高了约40%。

基于自组织模块化神经网络的污水处理过程出水参数预测

针对城市污水处理过程关键出水水质一些参数难以在线测量的问题,提出了一种基于经验模态分解(EMD)的自组织模块化神经网络(MNN)出水参数软测量模型。首先设计一种基于EMD的任务分解方法,将复杂的时间序列分解为若干子序列,并采用样本熵和欧氏距离分别计算子序列的复杂性及相似性,自适应调整子网络模块。然后针对子网络模块初始结构难以确定的问题提出一种前馈神经网络的结构自组织算法,实现子网络模型根据分配的子任务动态调整自身网络结构,更有效地对各子序列进行预测。最后通过基准时间序列预测和实际污水处理厂中出水水质参数检测实验验证了所提出的模型具有较好的预测精度和自适应性。

低载波比调制下的MMC-UPFC电容电压减频效应

低载波比(载波频率与基波频率之比)的载波移相调制策略可有效降低MMC-UPFC的开关损耗,但会导致“减频效应”造成电容电压谐波频率明显降低,严重削弱电容电压均衡策略的控制效果。根据电容电压谐波频率随载波比降低的规律,定量分析了低载波比调制下MMC-UPFC电容电压的减频效应,明确了低载波比与电容电压低频波动、子模块电容不稳定充放电状态和子模块间电容电压不均衡间的内在联系及其发生机理;在此基础上,提出一种基于RBF神经网络的减频效应抑制策略,通过检测电容电压的谐波分量进行最优载波比选择和电容电压控制。最后以苏州南部500kV UPFC示范工程为参考进行仿真,证明了MMC-UPFC电容电压的减频效应的存在性以及抑制方法的有效性。

基于机器视觉的导盲杖设计

【目的】为了满足视障人士多方面的实际出行需求,设计了一款基于机器视觉的导盲杖。【方法】该系统整体为模块化设计,采用了STM32F407VET6单片机和边缘智能计算K210芯片为核心。其机器视觉功能是利用神经网络和YOLOv2算法训练建立起模型,并对摄像头拍摄到的实时图像进行检测而实现的。系统自身具备陀螺仪姿态角度测量功能,通过判断系统旋转角度是否达到设定阈值,以此来判断使用者是否有摔倒迹象;系统还具有GPS定位功能,在突发情况下系统会通过串口发送AT指令控制GSM模块向紧急联络人发送位置信息。【结果】该系统各个功能经模拟测试,其机器视觉功能检测的正确率达到99%以上;姿态角度测量误差维持在1°以内;GPS和GSM功能可以定位并发送短信息。【结论】该系统的功能可满足视障人士基本的实际出行需要。此外,图像检测模型的建立,可为今后训练模型以检测更多物体,完善机器视觉功能,应对更多实际出行的情况。

模糊化的Modular模糊神经网络降水预报模型研究

以广西西南部前汛期5、6月25个气象站平均逐日降水量作为预报对象,采用自然正交分解方法和模糊化方法对输入因子预处理后,结合Modular模糊神经网络建立了一种新的降水预报模型,并进行了逐日业务预报应用试验。结果表明,该降水预报模型比常规Modular模糊神经网络方法及逐步回归方法有更高的预报精度,具有较好的业务应用前景。

模糊Modular神经网络在黄金矿区可持续发展能力评价模型中的应用

以黄金矿区可持续发展能力的评价为研究对象 ,以矿区REES系统经济、社会、环境、资源子系统的综合发展水平、可持续发展度以及相互之间的状态协调度作为评价指标 ,建立了模糊Modular神经网络评价模型。通过实例分析 ,证明该模型具有较好的泛化、学习和映射能力 ,对类似于可持续发展能力的非线性系统评价有一定的参考价值。

Modular-tree:一个自构筑的神经网络结构(英文)

提出了一种新颖的具有自构筑能力的神经网络结构,称之为Modular-tree和两个相应的自构筑算法。在此结构中,任何现存的前馈神经网络均可以作为子网。对于一个给定的学习任务,利用提出的生成算法通过对输入空间递归地划分,自动生成一树状的模块神经网络,从而避免了网络结构预置问题。由于使用了“分治”原理,Modular-tree具有良好的性能及快速训练的能力。此结构已用于多个监督学习问题(包括:标准测试及现实世界问题)并取得令人满意的实验结果。

基于机器学习的模块化多电平换流器的模型预测控制研究

模型预测控制器(model predictive controller,MPC)因可实现多目标优化控制被广泛应用在模块化多电平换流器(modular multilevel converter,MMC)领域,但随着子模块数量增加,MPC的在线计算量成几何级数增长。因此,提出了基于机器学习的MMC的模型预测控制方法,首先利用MPC-MMC仿真平台收集数据并对数据进行预处理,再进行神经网络训练得到神经网络-MPC(neural network-MPC,NN-MPC)。为了提高神经网络训练效率,采用随机森林来优化神经网络的初始权值和阈值,得到随机森林-神经网络-MPC(random forest-neural network-MPC,RF-NN-MPC),将其用来模拟MPC。仿真结果表明,RF-NN-MPC在学习效率和学习精度方面都优于NN-MPC,在保持了良好的控制效果的同时,使MPC-MMC不受子模块数量约束,在线计算量始终为1次。

基于RT-thread的小麦病虫害检测系统的研究与应用

【目的】为解决小麦病虫害问题,设计出一款基于RT-thread物联网操作系统的小麦病虫害检测系统。【方法】该检测系统以STM32H750XBH6单片机为核心主控板,使用神经网络对小麦病虫害进行识别。同时,该检测系统采用OneNET物联网云平台来实现数据的上行,并使用OneNET view组件实现对数据的二维显示。【结果】系统稳定运行后,能在多种恶劣环境中识别出不同的小麦病虫害问题,并通过调用数据库来给出该健康状况下的解决方案。【结论】该系统不仅能降低因小麦病虫害带来的损失,还能减少人力物力的投入。