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Discovery of β-nitrostyrene derivatives as potential quorum sensing inhibitors for biofilm inhibition and antivirulence factor therapeutics against Serratia marcescens
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作者 Jiang Wang Jingyi Yang +6 位作者 Pradeepraj Durairaj Wei Wang Dongyan Wei Shi Tang Haiqing Liu Dayong Wang Ai-Qun Jia 《mLife》 CSCD 2024年第3期445-458,共14页
Quorum sensing(Qs)inhibition has emerged as a promising target for directed drug design,providing an appealing strategy for developing antimicrobials,particularly against infections caused by drug-resistant pathogens.... Quorum sensing(Qs)inhibition has emerged as a promising target for directed drug design,providing an appealing strategy for developing antimicrobials,particularly against infections caused by drug-resistant pathogens.In this study,we designed and synthesized a total of 33β-nitrostyrene derivatives using 1-nitro-2-phenylethane(NPe)as the lead compound,to target the facultative anaerobic bacterial pathogen Serratia marcescens.The QS-inhibitory effects of these compounds were evaluated using S.marcescens NJ01 and the reporter strain Chromobacterium violaceum CV026.Among the 33 newβ-nitrostyrene derivatives,(E)-1-methyl-4-(2-nitrovinyl)benzene(m-NPe,compound 28)was proven to be a potent inhibitor that reduced biofilm formation of S.marcescens NJ01 by 79%.Scanning electron microscopy(SEM)and confocal laser scanning microscopy(CLSM)results revealed that treatment with m-NPe(50μg/ml)not only enhanced the susceptibility of the formed biofilms but also disrupted the architecture of biofilms by 84%.m-NPe(50μg/ml)decreased virulence factors in S.marcescens NJ01,reducing the activity of protease,prodigiosin,and extracellular polysaccharide(EPs)by 36%,72%,and 52%,respectively.In S.marcescens 4547,the activities of hemolysin and EPs were reduced by 28%and 40%,respectively,outperforming the positive control,vanillic acid(VAN).The study also found that the expression levels of QS-and biofilm-related genes(flhD,fimA,fimC,sodB,bsmB,pigA,pigC,and shlA)were downregulated by 1.21-to 2.32-fold.Molecular dynamics analysis showed that m-NPe could bind stably to SmaR,Rhll,RhiR,LasR,and CviR proteins in a 0.1 M sodium chloride solution.Importantly,a microscale thermophoresis(MST)test revealed that SmaR could be a target protein for the screening of a quorum sensing inhibitor(QSl)against S.marcescens.Overall,this study highlights the efficacy of m-NPe in suppressing the virulence factors of S.marcescens,identifying it as a new potential Qsl and antibiofilm agent capable of restoring or improving antimicrobial drug sensitivity. 展开更多
关键词 biofilms quorum sensing Serratia marcescens virulence factors (E)-1-methyl-4-(2-nitrovinyl)benzene
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Local Partial Least Squares Based Online Soft Sensing Method for Multi-output Processes with Adaptive Process States Division 被引量:3
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作者 邵伟明 田学民 王平 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2014年第7期828-836,共9页
Local learning based soft sensing methods succeed in coping with time-varying characteristics of processes as well as nonlinearities in industrial plants. In this paper, a local partial least squares based soft sensin... Local learning based soft sensing methods succeed in coping with time-varying characteristics of processes as well as nonlinearities in industrial plants. In this paper, a local partial least squares based soft sensing method for multi-output processes is proposed to accomplish process states division and local model adaptation,which are two key steps in development of local learning based soft sensors. An adaptive way of partitioning process states without redundancy is proposed based on F-test, where unique local time regions are extracted.Subsequently, a novel anti-over-fitting criterion is proposed for online local model adaptation which simultaneously considers the relationship between process variables and the information in labeled and unlabeled samples. Case study is carried out on two chemical processes and simulation results illustrate the superiorities of the proposed method from several aspects. 展开更多
关键词 Local learning Online soft sensing Partial least squares F-TEST Multi-output process Process state division
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Application in soft sensing modeling of chemical process based on K-OPLS method
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作者 LI Jun LI Kai 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2020年第1期17-27,共11页
Aiming at the problem of soft sensing modeling for chemical process with strong nonlinearity and complexity,a soft sensing modeling method based on kernel-based orthogonal projections to latent structures(K-OPLS)is pr... Aiming at the problem of soft sensing modeling for chemical process with strong nonlinearity and complexity,a soft sensing modeling method based on kernel-based orthogonal projections to latent structures(K-OPLS)is proposed.Orthogonal projections to latent structures(O-PLS)is a general linear multi-variable data modeling method.It can eliminate systematic variations from descriptive variables(input)that are orthogonal to response variables(output).In the framework of O-PLS model,K-OPLS method maps descriptive variables to high-dimensional feature space by using“kernel technique”to calculate predictive components and response-orthogonal components in the model.Therefore,the K-OPLS method gives the non-linear relationship between the descriptor and the response variables,which improves the performance of the model and enhances the interpretability of the model to a certain extent.To verify the validity of K-OPLS method,it was applied to soft sensing modeling of component content of debutane tower base butane(C4),the quality index of the key product output for industrial fluidized catalytic cracking unit(FCCU)and H 2S and SO 2 concentration in sulfur recovery unit(SRU).Compared with support vector machines(SVM),least-squares support-vector machine(LS-SVM),support vector machine with principal component analysis(PCA-SVM),extreme learning machine(ELM),kernel based extreme learning machine(KELM)and kernel based extreme learning machine with principal component analysis(PCA-KELM)methods under the same conditions,the experimental results show that the K-OPLS method has superior modeling accuracy and good model generalization ability. 展开更多
关键词 kernel method orthogonal projection to latent structures(K-OPLS) soft sensing chemical process
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Soft-Sensing Method of Water Temperature Measurement for Controlled Cooling System
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作者 CAIXiao-hui ZHANGDian-hua +2 位作者 WANGGuo-dong LIUXiang-hua FANLei 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2003年第4期71-74,共4页
Aiming at the water temperature measuring problem for controlled cooling system of rolling plant,a new water temperature measuring method based on soft-sensing method with a water temperature model of on-line self cor... Aiming at the water temperature measuring problem for controlled cooling system of rolling plant,a new water temperature measuring method based on soft-sensing method with a water temperature model of on-line self correction parameter was built.A water temperature compensation factor model was also built to improve coiling temperature control precision.It was proved that the model meets production requirements.The soft-sensing technique has extensive applications in the field of metal forming. 展开更多
关键词 soft-sensing controlled cooling water temperature model correction model
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Shadow Detection Method Based on HMRF with Soft Edges for High-Resolution Remote-Sensing Images
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作者 Wenying Ge 《Journal of Signal and Information Processing》 2019年第4期200-210,共11页
Shadow detection is a crucial task in high-resolution remote-sensing image processing. Various shadow detection methods have been explored during the last decades. These methods did improve the detection accuracy but ... Shadow detection is a crucial task in high-resolution remote-sensing image processing. Various shadow detection methods have been explored during the last decades. These methods did improve the detection accuracy but are still not robust enough to get satisfactory results for failing to extract enough information from the original images. To take full advantage of various features of shadows, a new method combining edges information with the spectral and spatial information is proposed in this paper. As known, edge is one of the most important characteristics in the high-resolution remote-sensing images. Unfortunately, in shadow detection, it is a high-risk strategy to determine whether a pixel is the edge or not strictly because intensity values on shadow boundaries are always between those in shadow and non-shadow areas. Therefore, a soft edge description model is developed to describe the degree of each pixel belonging to the edges or not. Sequentially, the soft edge description is incorporating to a fuzzy clustering procedure based on HMRF (Hidden Markov Random Fields), in which more appropriate spatial contextual information can be used. More concretely, it consists of two components: the soft edge description model and an iterative shadow detection algorithm. Experiments on several remote sensing images have shown that the proposed method can obtain more accurate shadow detection results. 展开更多
关键词 SHADOW Detection soft EDGES CLUSTERING REMOTE-sensing Images
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SOFT SENSING MODEL BASED ON SUPPORT VECTOR MACHINE AND ITS APPLICATION 被引量:3
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作者 YanWeiwu ShaoHuihe WangXiaofan 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2004年第1期55-58,共4页
Soft sensor is widely used in industrial process control. It plays animportant role to improve the quality of product and assure safety in production. The core of softsensor is to construct soft sensing model. A new s... Soft sensor is widely used in industrial process control. It plays animportant role to improve the quality of product and assure safety in production. The core of softsensor is to construct soft sensing model. A new soft sensing modeling method based on supportvector machine (SVM) is proposed. SVM is a new machine learning method based on statistical learningtheory and is powerful for the problem characterized by small sample, nonlinearity, high dimensionand local minima. The proposed methods are applied to the estimation of frozen point of light dieseloil in distillation column. The estimated outputs of soft sensing model based on SVM match the realvalues of frozen point and follow varying trend of frozen point very well. Experiment results showthat SVM provides a new effective method for soft sensing modeling and has promising application inindustrial process applications. 展开更多
关键词 soft sensor soft sensing MODELING Support vector machine
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A subspace ensemble regression model based slow feature for soft sensing application 被引量:1
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作者 Qiong Jia Jun Cai +1 位作者 Xinyi Jiang Shaojun Li 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2020年第12期3061-3069,共9页
A novel adaptive subspace ensemble slow feature regression model was developed for soft sensing application.Compared to traditional single models and random subspace models,the proposed method is improved in three asp... A novel adaptive subspace ensemble slow feature regression model was developed for soft sensing application.Compared to traditional single models and random subspace models,the proposed method is improved in three aspects.Firstly,sub-datasets are constructed through slow feature directions and variables in each subdatasets are selected according to the output related importance index.Then,an adaptive slow feature regression is presented for sub-models.Finally,a Bayesian inference strategy based on a slow feature analysis process that monitors statistics is developed for probabilistic combination.Two industrial examples were used to evaluate the proposed method. 展开更多
关键词 soft sensing Slow feature regression Subspace modeling Ensemble learning
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A new backtracking-based sparsity adaptive algorithm for distributed compressed sensing
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作者 徐勇 张玉洁 +1 位作者 邢婧 李宏伟 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第10期3946-3956,共11页
A new iterative greedy algorithm based on the backtracking technique was proposed for distributed compressed sensing(DCS) problem. The algorithm applies two mechanisms for precise recovery soft thresholding and cuttin... A new iterative greedy algorithm based on the backtracking technique was proposed for distributed compressed sensing(DCS) problem. The algorithm applies two mechanisms for precise recovery soft thresholding and cutting. It can reconstruct several compressed signals simultaneously even without any prior information of the sparsity, which makes it a potential candidate for many practical applications, but the numbers of non-zero(significant) coefficients of signals are not available. Numerical experiments are conducted to demonstrate the validity and high performance of the proposed algorithm, as compared to other existing strong DCS algorithms. 展开更多
关键词 distributed compressed sensing sparsiy BACKTRACKING soft thresholding
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ICNSC 2008 CALL FOR PAPERS 5th IEEE International Conference on Networking, Sensing and Control Sanya China April 6-8, 2008
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《控制理论与应用》 EI CAS CSCD 北大核心 2007年第3期512-512,共1页
Conference Theme Advanced Technologies for Emergency Planning and ResponseThe 2008 IEEE International Conference on Networking, Sensing and Control will be held in Sanya,China. The main theme of the conference is adva... Conference Theme Advanced Technologies for Emergency Planning and ResponseThe 2008 IEEE International Conference on Networking, Sensing and Control will be held in Sanya,China. The main theme of the conference is advanced technologies for emergency planning and re- 展开更多
关键词 IEEE CALL ICNSC 2008 CALL FOR PAPERS 5th IEEE International Conference on Networking sensing and Control Sanya China April 6-8
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Drone remote sensing for forestry research and practices 被引量:24
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作者 Lina Tang Guofan Shao 《Journal of Forestry Research》 SCIE CAS CSCD 2015年第4期791-797,共7页
Drones of various shapes, sizes, and functionalities have emerged over the past few decades, and their civilian applications are becoming increasingly appealing. Flexible, low-cost, and high-resolution remote sensing ... Drones of various shapes, sizes, and functionalities have emerged over the past few decades, and their civilian applications are becoming increasingly appealing. Flexible, low-cost, and high-resolution remote sensing systems that use drones as platforms are important for filling data gaps and supplementing the capabilities of crewed/manned aircraft and satellite remote sensing systems. Here, we refer to this growing remote sensing ini- tiative as drone remote sensing and explain its unique advantages in forestry research and practices. Furthermore, we summarize the various approaches of drone remote sensing to surveying forests, mapping canopy gaps, mea- suring forest canopy height, tracking forest wildfires, and supporting intensive forest management. The benefits of drone remote sensing include low material and operational costs, flexible control of spatial and temporal resolution, high-intensity data collection, and the absence of risk to crews. The current forestry applications of drone remote sensing are still at an experimental stage, but they are expected to expand rapidly. To better guide the development of drone remote sensing for sustainable forestry, it isimportant to systematically and continuously conduct comparative studies to determine the appropriate drone remote sensing technologies for various forest conditions and/or forestry applications. 展开更多
关键词 Drone - Remote sensing UAV UAS UA -RPA· Forest
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基于FRBPSO-RBF神经网络的污水BOD5软测量方法 被引量:1
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作者 班慧琳 李中志 +1 位作者 李斌勇 王远 《成都信息工程大学学报》 2024年第4期416-421,共6页
污水处理过程中污水BOD5难以实时准确测量,故软测量方法逐渐被用于污水BOD5的预测,其中RBF神经网络软测量方法应用广泛,但存在训练过程易陷入局部极值等问题。为提高RBF神经网络的预测精度,提出了基于适应度排名的粒子群算法(fitness ra... 污水处理过程中污水BOD5难以实时准确测量,故软测量方法逐渐被用于污水BOD5的预测,其中RBF神经网络软测量方法应用广泛,但存在训练过程易陷入局部极值等问题。为提高RBF神经网络的预测精度,提出了基于适应度排名的粒子群算法(fitness ranking based particle swarm optimization,FRBPSO),根据适应度排名与迭代次数确定惯性权重的大小,并根据粒子个体历史最优值的排名与迭代次数确定自我学习因子与社会学习因子的大小,并将FRBPSO算法引入RBF神经网络的参数训练中。基于13个基准测试函数与其他3个粒子群优化算法对比,实验结果显示FRBPSO算法的寻优能力相对较强。再将基于FRBPSO算法的RBF神经网络用于构建污水BOD5软测量模型,仿真结果表明,在测试数据中,FRBPSO-RBF软测量模型的平均绝对误差比PSO-RBF软测量模型、DAIW-RBF软测量模型、SCVPSO-RBF软测量模型分别降低了0.7178、0.2402、0.5851,平均绝对百分比误差分别降低了0.47%、0.15%、0.33%,均方根误差分别降低了0.0034、0.0015、0.0039。与其他3个基于PSO算法的BOD5软测量模型相比,FRBPSO-RBF模型具有较高的BOD5预测精度。 展开更多
关键词 RBF神经网络 PSO算法 软测量模型 BOD5软测量 污水水质预测
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基于主成分分析-改进的极限学习机方法的精对苯二甲酸醋酸含量软测量 被引量:26
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作者 贺彦林 王晓 朱群雄 《控制理论与应用》 EI CAS CSCD 北大核心 2015年第1期80-85,共6页
目前,化工生产过程日益复杂,生产操作变量越来越多,由于客观条件的限制,有些重要的过程参数无法通过直接测量的手段精确测得.通过软测量可实现复杂化工生产过程重要参数的精确测量,进而指导化工企业的生产,提高化工生产的产出效率,是解... 目前,化工生产过程日益复杂,生产操作变量越来越多,由于客观条件的限制,有些重要的过程参数无法通过直接测量的手段精确测得.通过软测量可实现复杂化工生产过程重要参数的精确测量,进而指导化工企业的生产,提高化工生产的产出效率,是解决问题的一个有效的方法.针对复杂化工过程软测量建模中存在的问题,本文提出了一种改进的极限学习机模型(improved extreme learning machine,IELM).一方面将主成分分析(principal component analysis,PCA)方法应用到极限学习机(ELM)里,通过PCA对模型输入变量进行主成分分析,不仅去除了变量间的线性相关关系,而且对高数据进行降维处理,最终降低了极限学习机的输入复杂性;另一方面利用相关系数判断输入主元数据与输出数据间的相关关系,从而得到正相关输入和负相关输入,依据这两类数据构造ELM模型,使得每类输入数据对网络的输出有同样的作用,进一步提高极限学习机的泛化能力.最后建立了PCA-IELM模型,首先用标准数据库的Triazines数据集验证该模型有效性,随后得出了基于PCA-IELM方法的精对苯二甲酸(purified terephthalic acid,PTA)溶剂脱水塔塔顶醋酸含量软测量模型,仿真结果表明PCA-IELM模型处理高维数据时较传统的ELM算法具有稳定性好,建模精度高等特点,为神经网络在复杂化工应用领域提供新思路. 展开更多
关键词 极限学习机 主成分分析 精对苯二甲酸 软测量
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基于改进k-最近邻回归算法的软测量建模 被引量:15
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作者 叶涛 朱学峰 +1 位作者 李向阳 史步海 《自动化学报》 EI CSCD 北大核心 2007年第9期996-999,共4页
机器学习回归方法被广泛应用于复杂工业过程的软测量建模k-最近邻(kNN)算法是一种流行的学习算法,可用于函数回归问题.然而,传统kNN算法存在运行效率低、距离计算忽略特征权值的缺点.本文引入了二次型距离定义和样本集剪辑算法,改进了传... 机器学习回归方法被广泛应用于复杂工业过程的软测量建模k-最近邻(kNN)算法是一种流行的学习算法,可用于函数回归问题.然而,传统kNN算法存在运行效率低、距离计算忽略特征权值的缺点.本文引入了二次型距离定义和样本集剪辑算法,改进了传统kNN回归算法,并将改进的算法用于工业过程软测量建模.仿真实验得到了一些有益的结论. 展开更多
关键词 K-最近邻算法 二次型距离 软测量 纸浆KAPPA值
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基于DPCA-RBF网络的工业流化床乙烯气相聚合过程的软测量研究 被引量:6
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作者 杨敏 胡斌 +2 位作者 费正顺 郑平友 梁军 《仪器仪表学报》 EI CAS CSCD 北大核心 2010年第3期481-487,共7页
工业流化床乙烯气相聚合反应是一个复杂的生产过程,具有高维、非线性、动态性和强噪声特点,质量变量难以直接测量。为解决关键质量变量在线软测量问题,首先采用动态主元分析(DPCA)的方法对过程变量提取主元,消除了过程变量之间的相关性... 工业流化床乙烯气相聚合反应是一个复杂的生产过程,具有高维、非线性、动态性和强噪声特点,质量变量难以直接测量。为解决关键质量变量在线软测量问题,首先采用动态主元分析(DPCA)的方法对过程变量提取主元,消除了过程变量之间的相关性、噪声并体现了建模数据的动态特性;其次对提取出的主元变量采用径向基函数网络(RBF)建模的方法,建立主元变量和质量变量之间的网络结构。对纯函数数据以及工业现场数据分别进行PCA-RBF模型及DPCA-RBF模型的仿真研究,研究结果表明,当建模数据存在非线性、动态性、噪声以及相关性等特性时,DPCA-RBF建模方法比PCA-RBF及单纯的RBF建模方法更优越。因此,DPCA-RBF建模方法较适合运用在工业实时变量的软测量中。 展开更多
关键词 乙烯气相聚合 动态主元分析 RBF神经网络 软测量
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基于动态数据交换技术的海洋蛋白酶发酵过程GD-FNN软测量 被引量:3
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作者 黄永红 孙丽娜 +2 位作者 孙玉坤 刘国海 聂文惠 《农业工程学报》 EI CAS CSCD 北大核心 2013年第19期268-276,共9页
为实现微生物发酵过程中关键生物参数(菌体浓度、基质浓度、产物浓度等)的实时显示与存储,该文结合MATLAB与WinCC各自的优势,提出了一种基于动态数据交换(dynamic data exchange,DDE)技术的广义动态模糊神经网络(generalized dynamic fu... 为实现微生物发酵过程中关键生物参数(菌体浓度、基质浓度、产物浓度等)的实时显示与存储,该文结合MATLAB与WinCC各自的优势,提出了一种基于动态数据交换(dynamic data exchange,DDE)技术的广义动态模糊神经网络(generalized dynamic fuzzy neural network,GD-FNN)软测量方法。以海洋蛋白酶发酵过程为研究对象,通过MATLAB编程,建立发酵过程GD-FNN软测量模型,获得生物参数的预测值;以Excel软件为中间桥梁,利用DDE技术实现MATLAB与上位机WinCC之间的实时数据通讯,最终获得了生物参数的实时显示与存储。应用结果表明,利用GD-FNN所建立的生物参数软测量模型具有很高的预测精度,所得的最大均方根误差为0.4266,最大平均绝对误差为0.2552,满足系统测量的精度要求;同时通过DDE技术连接MATLAB与WinCC,编程效率高,实现方便,通用性强。该研究为发酵过程的优化控制以及工业化生产提供了依据。 展开更多
关键词 微生物 发酵 神经网络 动态数据交换 软测量
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结合PLS-DA与SVM的近红外光谱软测量方法 被引量:13
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作者 董学锋 戴连奎 黄承伟 《浙江大学学报(工学版)》 EI CAS CSCD 北大核心 2012年第5期824-829,共6页
为了提高近红外光谱分析精度,提出结合偏最小二乘判别分析(PLS-DA)与支持向量机(SVM)的软测量方法(PLS-DA-SVM).该方法利用一组由不同类别组成的训练样本,引入二叉树进行多重分类,节点分类器由PLS-DA方法建立;利用偏最小二乘支持向量机(... 为了提高近红外光谱分析精度,提出结合偏最小二乘判别分析(PLS-DA)与支持向量机(SVM)的软测量方法(PLS-DA-SVM).该方法利用一组由不同类别组成的训练样本,引入二叉树进行多重分类,节点分类器由PLS-DA方法建立;利用偏最小二乘支持向量机(PLS-SVM)建立每类样本的定量模型.预测时,用PLS-DA分类树对待测样本进行分类,选择相应的PLS-SVM模型进行定量分析.实验利用PLS-DA-SVM方法和近红外光谱数据建立汽油的研究法辛烷值软测量模型,针对2个批次共计57个成品汽油样本进行蒙特卡洛交叉检验.结果表明,对汽油牌号进行识别,平均分类错误率为0.07%,低于其他常用分类方法;对研究法辛烷值进行预测,均方误差达到0.243,复相关系数达到0.991,较PLS、LS-SVM等方法有显著提高. 展开更多
关键词 软测量 近红外光谱 偏最小二乘 支持向量机
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基于聚类动态LS-SVM的L-赖氨酸发酵过程软测量方法 被引量:14
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作者 孙玉坤 王博 +1 位作者 黄永红 嵇小辅 《仪器仪表学报》 EI CAS CSCD 北大核心 2010年第2期404-409,共6页
针对生化反应过程中软测量模型存在的模型失效问题,提出了一种基于模糊C均值聚类(FCM)和动态LS-SVM的混合建模方法。首先,采用FCM算法将训练集分成具有不同聚类中心的子集,然后对每一类分别采用LS-SVM进行训练并建立子模型。对于带有新... 针对生化反应过程中软测量模型存在的模型失效问题,提出了一种基于模糊C均值聚类(FCM)和动态LS-SVM的混合建模方法。首先,采用FCM算法将训练集分成具有不同聚类中心的子集,然后对每一类分别采用LS-SVM进行训练并建立子模型。对于带有新信息的样本数据首先计算其对每一类的模糊隶属度函数,然后用隶属度最大的一类所对应的子模型进行动态学习,并更新子模型。将所提出的软测量建模方法用于对L-赖氨酸发酵过程关键生物量参数的预测,实验结果表明所提出的建模方法可以有效地增强软测量模型适应工况变化的能力,提高其预测精度。 展开更多
关键词 软测量 模糊C均值聚类 动态最小二乘支持向量机 L-赖氨酸发酵过程
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基于PCA-RBF神经网络的工业裂解炉收率在线预测软测量方法 被引量:15
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作者 杨尔辅 周强 +1 位作者 胡益锋 徐用懋 《系统仿真学报》 CAS CSCD 2001年第z1期194-197,共4页
为了解决工业裂解炉收率在线预测的问题,研究了基于PCA(principal component analysis)-RBF(radial basis function)神经网络模型的多输入多输出(MIMO)软测量方法及其在线校正技术。该方法由主元分析PCA、RBF神经网络和在线校正3部分组... 为了解决工业裂解炉收率在线预测的问题,研究了基于PCA(principal component analysis)-RBF(radial basis function)神经网络模型的多输入多输出(MIMO)软测量方法及其在线校正技术。该方法由主元分析PCA、RBF神经网络和在线校正3部分组成,可以实现工业裂解炉收率的在线预测,具有实时性好、建模周期短、计算量小、校正方便等特点。本文给出的SRT-IV型工业裂解炉收率预测例子及其结果表明该软测量方法应用于工业裂解炉收率的在线预测是有效的。 展开更多
关键词 过程建模 软测量 神经网络 主元分析 裂解炉 乙烯过程
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基于DJMI-GRU的SCR烟气脱硝系统出口NO_(x)动态软测量建模 被引量:7
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作者 杨浩 周东阳 +2 位作者 曹军 董云山 司风琪 《热力发电》 CAS CSCD 北大核心 2021年第12期51-58,共8页
燃煤电站烟气连续监测系统(CEMS)反向吹灰时,烟气NO_(x)质量浓度信号容易失真,从而造成喷氨量不匹配、NO_(x)排放超限等问题。本文考虑选择性催化还原(SCR)烟气脱硝系统的时延特性,采用差分联合互信息(DJMI)方法确定影响SCR反应器出口NO... 燃煤电站烟气连续监测系统(CEMS)反向吹灰时,烟气NO_(x)质量浓度信号容易失真,从而造成喷氨量不匹配、NO_(x)排放超限等问题。本文考虑选择性催化还原(SCR)烟气脱硝系统的时延特性,采用差分联合互信息(DJMI)方法确定影响SCR反应器出口NO_(x)质量浓度的辅助变量时延和动态模型输入的历史数据长度,提出了一种基于门控循环单元(GRU)神经网络的DJMI-GRU动态软测量方法。利用某660 MW机组历史数据对软测量模型进行验证,并与普通循环神经网络(RNN)模型进行比较。结果表明:与RNN模型相比,GRU神经网络结构具有遗忘更新机制,利用全工况数据训练时具有较好的泛化能力;采用DJMI方法估计时延信息并重构输入数据集能有效去除DJMI-GRU模型输入中的冗余信息,更好地表现脱硝过程的动态特性并加速模型训练;使用局部工况数据进行模型训练时计算量小且能取得更高的拟合精度,能在CEMS反向吹灰时为喷氨优化、NO_(x)排放监测提供指导。 展开更多
关键词 烟气脱硝 NO_(x) SCR CEMS 软测量 DJMI GRU 神经网络
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基于IRLS-ELM生物发酵在线软测量建模方法 被引量:5
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作者 刘国海 张东娟 梅从立 《东南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2011年第B09期10-13,共4页
为解决生物发酵过程中生物量浓度难以在线测量的问题,提出一种基于改进的最小二乘正则化极限学习机(IRLS-ELM)软测量建模方法并将其应用于红霉素发酵过程生物量浓度的在线预测中.根据误差反馈原理,将训练误差作为输入建立带反馈的神经网... 为解决生物发酵过程中生物量浓度难以在线测量的问题,提出一种基于改进的最小二乘正则化极限学习机(IRLS-ELM)软测量建模方法并将其应用于红霉素发酵过程生物量浓度的在线预测中.根据误差反馈原理,将训练误差作为输入建立带反馈的神经网络,以提高模型预测精度.并将加权最小二乘法引入到ELM中改进其数学模型,削弱离群点或者不稳定因素的影响.最后,将所建IRLS-ELM模型应用于红霉素发酵过程生物量浓度的预测中.实验结果表明,在隐含层节点数相同的情况下,对于指标MSE,IRLS-ELM比ELM和RLS-ELM有明显提高.同时IRLS-ELM在隐含层节点数变少的情况下,误差没有明显变化,结构紧凑而且稳定性较高.由此可见,与ELM和RLS-ELM软测量建模方法相比,IRLS-ELM在线软测量建模方法具有更高的预测精度和更强的泛化能力. 展开更多
关键词 极限学习机 软测量 反馈输入 发酵过程
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