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A Novel Method for Flatness Pattern Recognition via Least Squares Support Vector Regression 被引量:12
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作者 ZHANG Xiu-ling, ZHANG Shao-yu, TAN Guang-zhong, ZHAO Wen-bao (Key Laboratory of Industrial Computer Control Engineering of Hebei Province, National Engineering Research Center for Equipment and Technology of Cold Strip Rolling, Yanshan University, Qinhuangdao 066004, Hebei, China) 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2012年第3期25-30,共6页
To adapt to the new requirement of the developing flatness control theory and technology, cubic patterns were introduced on the basis of the traditional linear, quadratic and quartic flatness basic patterns. Linear, q... To adapt to the new requirement of the developing flatness control theory and technology, cubic patterns were introduced on the basis of the traditional linear, quadratic and quartic flatness basic patterns. Linear, quadratic, cubic and quartic Legendre orthogonal polynomials were adopted to express the flatness basic patterns. In order to over- come the defects live in the existent recognition methods based on fuzzy, neural network and support vector regres- sion (SVR) theory, a novel flatness pattern recognition method based on least squares support vector regression (LS-SVR) was proposed. On this basis, for the purpose of determining the hyper-parameters of LS-SVR effectively and enhan- cing the recognition accuracy and generalization performance of the model, particle swarm optimization algorithm with leave-one-out (LOO) error as fitness function was adopted. To overcome the disadvantage of high computational complexity of naive cross-validation algorithm, a novel fast cross-validation algorithm was introduced to calculate the LOO error of LDSVR. Results of experiments on flatness data calculated by theory and a 900HC cold-rolling mill practically measured flatness signals demonstrate that the proposed approach can distinguish the types and define the magnitudes of the flatness defects effectively with high accuracy, high speed and strong generalization ability. 展开更多
关键词 flatness pattern recognition least squares support vector regression cross-validation
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Ignition Pattern Analysis for Automotive Engine Trouble Diagnosis Using Wavelet Packet Transform and Support Vector Machines 被引量:11
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作者 VONG Chi-man WONG Pak-kin +1 位作者 TAM Lap-mou ZHANG Zaiyong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2011年第5期870-878,共9页
Engine spark ignition is an important source for diagnosis of engine faults.Based on the waveform of the ignition pattern,a mechanic can guess what may be the potential malfunctioning parts of an engine with his/her e... Engine spark ignition is an important source for diagnosis of engine faults.Based on the waveform of the ignition pattern,a mechanic can guess what may be the potential malfunctioning parts of an engine with his/her experience and handbooks.However,this manual diagnostic method is imprecise because many spark ignition patterns are very similar.Therefore,a diagnosis needs many trials to identify the malfunctioning parts.Meanwhile the mechanic needs to disassemble and assemble the engine parts for verification.To tackle this problem,an intelligent diagnosis system was established based on ignition patterns.First,the captured patterns were normalized and compressed.Then wavelet packet transform(WPT) was employed to extract the representative features of the ignition patterns.Finally,a classification system was constructed by using multi-class support vector machines(SVM) and the extracted features.The classification system can intelligently classify the most likely engine fault so as to reduce the number of diagnosis trials.Experimental results show that SVM produces higher diagnosis accuracy than the traditional multilayer feedforward neural network.This is the first trial on the combination of WPT and SVM to analyze ignition patterns and diagnose automotive engines. 展开更多
关键词 automotive engine ignition pattern diagnosis pattern classification wavelet packet transform support vector machines.
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A Review of Agricultural Pesticides Use and the Selection for Resistance to Insecticides in Malaria Vectors 被引量:4
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作者 Anitha Philbert Sylvester Leonard Lyantagaye Gamba Nkwengulila 《Advances in Entomology》 2014年第3期120-128,共9页
Most national malaria control programmes rely extensively on pyrethroid insecticides to control mosquito vectors of this disease. Unfortunately, the intensive use of this class of insecticides both in public health an... Most national malaria control programmes rely extensively on pyrethroid insecticides to control mosquito vectors of this disease. Unfortunately, the intensive use of this class of insecticides both in public health and agriculture has led to its reduced efficacy. The objective of this review was to assess the role of agricultural pesticides use on the development of resistance to insecticides in malaria vectors and the potential impact of this resistance on control activities. We searched library catalogues and public databases for studies that included data on resistance to the major classes of insecticides: organochlorines, carbamates, organophosphates and pyrethroids, in the malaria vectors of Anopheles genera. There is a strong geographical bias in published studies many originating from West African countries. Several studies demonstrate that resistance to pyrethroids is widespread in the major malaria vectors of the Anopheles gambiae and Anopheles funestus complexes. Assessing the impact of insecticide resistance on vector control is complicated owing to the lack of studies into the epidemiological consequences of resistance on the control of malaria and other vector borne diseases. 展开更多
关键词 INSECTICIDE RESISTANCE MALARIA vectors RESISTANCE patterns Agro PESTICIDE PYRETHROIDS
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Least Squares Support Vector Machine Based Real-Time Fault Diagnosis Model for Gas Path Parameters of Aero Engines 被引量:2
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作者 王旭辉 黄圣国 +2 位作者 王烨 刘永建 舒平 《Journal of Southwest Jiaotong University(English Edition)》 2009年第1期22-26,共5页
Least squares support vector machine (LS-SVM) is applied in gas path fault diagnosis for aero engines. Firstly, the deviation data of engine cruise are analyzed. Then, model selection is conducted using pattern sear... Least squares support vector machine (LS-SVM) is applied in gas path fault diagnosis for aero engines. Firstly, the deviation data of engine cruise are analyzed. Then, model selection is conducted using pattern search method. Finally, by decoding aircraft communication addressing and reporting system (ACARS) report, a real-time cruise data set is acquired, and the diagnosis model is adopted to process data. In contrast to the radial basis function (RBF) neutral network, LS-SVM is more suitable for real-time diagnosis of gas turbine engine. 展开更多
关键词 Engine diagnosis Gas path Least squares support vector machine pattern search
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Fast Training of Support Vector Machines Using Error-Center-Based Optimization 被引量:3
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作者 L. Meng, Q. H. Wu Department of Electrical Engineering and Electronics, The University of Liverpool, Liverpool, L69 3GJ, UK 《International Journal of Automation and computing》 EI 2005年第1期6-12,共7页
This paper presents a new algorithm for Support Vector Machine (SVM) training, which trains a machine based on the cluster centers of errors caused by the current machine. Experiments with various training sets show t... This paper presents a new algorithm for Support Vector Machine (SVM) training, which trains a machine based on the cluster centers of errors caused by the current machine. Experiments with various training sets show that the computation time of this new algorithm scales almost linear with training set size and thus may be applied to much larger training sets, in comparison to standard quadratic programming (QP) techniques. 展开更多
关键词 Support vector machines quadratic programming pattern classification machine learning
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Forecasting regional economic growth using support vector machine model 被引量:1
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作者 ZHANG Kun 《Ecological Economy》 2019年第3期186-192,共7页
Support vector machine(SVM)is a new technology in data mining.It is a new tool to solve machine learning problems with the help of optimization.Support vector machines belong to a new machine learning that extends fro... Support vector machine(SVM)is a new technology in data mining.It is a new tool to solve machine learning problems with the help of optimization.Support vector machines belong to a new machine learning that extends from statistical learning theory.Its structure is relatively simple,with good generalization ability and global optimality.Support vector machine has provided a unified framework for solving finite sample learning problems,and there are many solutions proposed.It can deal with those more complex problems and introduce the characteristics of the support vector machine model.Aiming at the application of the model in economic forecasting,a method to improve the prediction accuracy of the model is proposed.The theoretical analysis and practical application verification are performed,which shows that this method can obtain more accurate prediction results. 展开更多
关键词 support vector MACHINE pattern RECOGNITION ECONOMIC growth FORECAST
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Hooke and Jeeves algorithm for linear support vector machine 被引量:1
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作者 Yeqing Liu Sanyang Liu Mingtao Gu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第1期138-141,共4页
Coordinate descent method is a unconstrained optimization technique. When it is applied to support vector machine (SVM), at each step the method updates one component of w by solving a one-variable sub-problem while... Coordinate descent method is a unconstrained optimization technique. When it is applied to support vector machine (SVM), at each step the method updates one component of w by solving a one-variable sub-problem while fixing other components. All components of w update after one iteration. Then go to next iteration. Though the method converges and converges fast in the beginning, it converges slow for final convergence. To improve the speed of final convergence of coordinate descent method, Hooke and Jeeves algorithm which adds pattern search after every iteration in coordinate descent method was applied to SVM and a global Newton algorithm was used to solve one-variable subproblems. We proved the convergence of the algorithm. Experimental results show Hooke and Jeeves' method does accelerate convergence specially for final convergence and achieves higher testing accuracy more quickly in classification. 展开更多
关键词 support vector machine CLASSIFICATION pattern search Hooke and Jeeves coordinate descent global Newton algorithm.
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Automatic signal detection based on support vector machine
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作者 王海军 刘贵忠 《Acta Seismologica Sinica(English Edition)》 CSCD 2007年第1期88-97,共10页
Algorithm of STA/LTA is frequently used in automatic signal detection, in which the range of detection threshold is (0, ∞), the optimal threshold should be determined by experiment to make a balance between false d... Algorithm of STA/LTA is frequently used in automatic signal detection, in which the range of detection threshold is (0, ∞), the optimal threshold should be determined by experiment to make a balance between false detection and missing detection. By using the theory of pattern recognition, a new algorithm for automatic signal detection based on support vector machine was proposed and the method of preprocess and pattern feature extraction were dis- cussed as well as the selection of kernel function for support vector machine. The detection performance of the new algorithm was analyzed by means of real seismic data. The experiments showed that the new method could simplify the selection of threshold and detect signal accurately. In addition to the better performance of anti-noise, the ratio of false detection could decrease 85% in comparison with that of STA/LTA. 展开更多
关键词 support vector machine EARTHQUAKE automatic processing pattern recognition
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Dynamic Spatial Discrimination Maps of Discriminative Activation between Different Tasks Based on Support Vector Machines
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作者 Guangxin Huang Huafu Chen Feng Yin 《Applied Mathematics》 2011年第1期85-92,共8页
As a set of supervised pattern recognition methods, support vector machines (SVMs) have been successfully applied to functional magnetic resonance imaging (fMRI) field, but few studies have focused on visualizing disc... As a set of supervised pattern recognition methods, support vector machines (SVMs) have been successfully applied to functional magnetic resonance imaging (fMRI) field, but few studies have focused on visualizing discriminative regions of whole brain between different cognitive tasks dynamically. This paper presents a SVM-based method for visualizing dynamically discriminative activation of whole-brain voxels between two kinds of tasks without any contrast. Our method provides a series of dynamic spatial discrimination maps (DSDMs), representing the temporal evolution of discriminative brain activation during a duty cycle and describing how the discriminating information changes over the duty cycle. The proposed method was applied to investigate discriminative brain functional activations of whole brain voxels dynamically based on a hand-motor task experiment. A set of DSDMs between left hand movement and right hand movement were reached. Our results demonstrated not only where but also when the discriminative activations of whole brain voxels occurred between left hand movement and right hand movement during one duty cycle. 展开更多
关键词 Functional Magnetic RESONANCE Imaging Principal Component Analysis Support vector Machine pattern Recognition Methods Maximum-Margin HYPERPLANE
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Training Robust Support Vector Machine Based on a New Loss Function
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作者 刘叶青 《Journal of Donghua University(English Edition)》 EI CAS 2015年第2期261-263,共3页
To reduce the influences of outliers on support vector machine(SVM) classification problem,a new tangent loss function was constructed.Since the tangent loss function was not smooth in some interval,a smoothing functi... To reduce the influences of outliers on support vector machine(SVM) classification problem,a new tangent loss function was constructed.Since the tangent loss function was not smooth in some interval,a smoothing function was used to approximate it in this interval.According to this loss function,the corresponding tangent SVM(TSVM) was got.The experimental results show that TSVM is less sensitive to outliers than SVM.So the proposed new loss function and TSVM are both effective. 展开更多
关键词 smoothing tangent approximate hinge Training classifier intuitive kernel quadratic retain
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基于自适应反馈机制的小差异化图像纹理特征信息数据检索
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作者 刘洋 毛克明 《江苏大学学报(自然科学版)》 CAS 北大核心 2025年第1期73-81,共9页
针对小差异化图像纹理相似度和噪声等因素导致纹理特征挖掘效果较差的问题,设计一种自适应反馈结合局部二值机制的小差异化图像纹理特征挖掘方法.使用规范割策略将图像数据各点拟作节点,使用节点间的连接线权重计算2点的相似度,采用支... 针对小差异化图像纹理相似度和噪声等因素导致纹理特征挖掘效果较差的问题,设计一种自适应反馈结合局部二值机制的小差异化图像纹理特征挖掘方法.使用规范割策略将图像数据各点拟作节点,使用节点间的连接线权重计算2点的相似度,采用支持向量机训练图像属性参数分类图像属性,进一步归纳图像类别.运用跳跃连接方法传输图像数据,将数据引入卷积神经网络剔除图像噪声.将中心点像素值当作反馈因子,创建自适应反馈判定条件,利用局部二值模式实现小差异化图像纹理特征挖掘.在MATLAB平台进行试验,从卷积神经网络收敛性、图像频谱纹理单元数、平均准确率、图像数据匹配度等方面进行了分析,分析结果表明:随着迭代次数不断增加,精度损失逐渐降低,基本收敛到稳定值,达到了预期训练效果;所提出方法挖掘的图像频谱纹理单元数3800个以上,更贴合人眼视觉信息;平均准确率为0.87,准确率@1、准确率@5和准确率@10的平均值分别为0.90、0.84和0.85;挖掘耗时低于5 s,图像数据匹配度高于90.3%,验证了所提出方法可在图像纹理特征识别操作中发挥应有作用. 展开更多
关键词 小差异化图像 纹理特征 数据挖掘 自适应反馈 属性分类 跳跃连接 局部二值模式 支持向量机
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基于图元变换的建筑彩绘纹样图像矢量化方法
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作者 曹力 张腾腾 +2 位作者 颜子麦 龚辰晨 赵洋 《计算机应用研究》 北大核心 2025年第7期2206-2212,共7页
为了对包含可复用图元的建筑彩绘纹样图像进行矢量化,并保留图像中可复用图元的独立性与变换参数,提出一种基于图元变换的建筑彩绘纹样图像矢量化方法。该方法首先将复杂彩绘纹样划分为局部纹样;然后对局部纹样进行图元多分类检测,完成... 为了对包含可复用图元的建筑彩绘纹样图像进行矢量化,并保留图像中可复用图元的独立性与变换参数,提出一种基于图元变换的建筑彩绘纹样图像矢量化方法。该方法首先将复杂彩绘纹样划分为局部纹样;然后对局部纹样进行图元多分类检测,完成图元过滤和图元变换参数初始化;再基于改进的可微合成算法计算图元的变换参数;最终完成纹样图像的保留可复用图元变换参数的矢量化。实验结果表明,在建筑彩绘纹样数据集上能够达到较小的图像重建误差,同时保留了可复用图元的变换参数。根据彩绘纹样特点提出了多种矢量化指标,比较了各类方法的性能,该方法在重建精度与图元变换参数保留方面具有优势,可应用于建筑彩绘纹样等具有图元可复用特点的图像矢量化。 展开更多
关键词 图像矢量化 图像模式 残差网络 图像分类 可微图像合成
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设施农业政策影响下的乡村空间形态演变研究——以大五福玛村为例
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作者 张宇 周成 董丽 《华中建筑》 2025年第3期176-180,共5页
在乡村振兴的时代背景下,设施农业政策通过调整乡村产业发展,影响设施大棚的建设,进而引起乡村空间形态的演变。该文以齐齐哈尔市大五福玛村为研究对象,梳理设施农业相关政策,运用向量自回归模型和景观格局分析法,多尺度分析乡村空间形... 在乡村振兴的时代背景下,设施农业政策通过调整乡村产业发展,影响设施大棚的建设,进而引起乡村空间形态的演变。该文以齐齐哈尔市大五福玛村为研究对象,梳理设施农业相关政策,运用向量自回归模型和景观格局分析法,多尺度分析乡村空间形态的演变特征,探索乡村空间形态演变规律与政策的关联性。研究发现:在以设施农业为主要产业的乡村中,设施农业政策对乡村空间形态各个层面的演变均有一定影响,这种影响表现出时滞性;在政策实施前期,对乡村空间边界和产业空间的影响较大,后期趋向稳定;对生活空间的发展具有抑制效果。此外,该文采用计量经济模型定量分析乡村空间形态与政策的相关性,对于新时代研究政策影响下的乡村空间形态演变具有积极指引意义。 展开更多
关键词 设施农业政策 乡村设施农业 空间形态演变 向量自回归模型
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Optimized Complex Power Quality Classifier Using One vs. Rest Support Vector Machines 被引量:1
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作者 David De Yong Sudipto Bhowmik Fernando Magnago 《Energy and Power Engineering》 2017年第10期568-587,共20页
Nowadays, power quality issues are becoming a significant research topic because of the increasing inclusion of very sensitive devices and considerable renewable energy sources. In general, most of the previous power ... Nowadays, power quality issues are becoming a significant research topic because of the increasing inclusion of very sensitive devices and considerable renewable energy sources. In general, most of the previous power quality classification techniques focused on single power quality events and did not include an optimal feature selection process. This paper presents a classification system that employs Wavelet Transform and the RMS profile to extract the main features of the measured waveforms containing either single or complex disturbances. A data mining process is designed to select the optimal set of features that better describes each disturbance present in the waveform. Support Vector Machine binary classifiers organized in a “One Vs Rest” architecture are individually optimized to classify single and complex disturbances. The parameters that rule the performance of each binary classifier are also individually adjusted using a grid search algorithm that helps them achieve optimal performance. This specialized process significantly improves the total classification accuracy. Several single and complex disturbances were simulated in order to train and test the algorithm. The results show that the classifier is capable of identifying >99% of single disturbances and >97% of complex disturbances. 展开更多
关键词 Complex Power Quality Optimal Feature Selection ONE vs. REST Support vector Machine Learning Algorithms WAVELET Transform pattern Recognition
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一种多尺度特征融合运动想象脑电信号分类算法——基于时频域数据增强
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作者 郑敏敏 钱政康 赵桐 《莆田学院学报》 2025年第2期52-60,70,共10页
针对传统的脑电信号识别算法样本量较小、识别分类准确率较低的问题,提出了一种基于时频域数据增强的多尺度特征融合运动想象脑电信号分类算法。对原始信号进行独立主成分分析滤除眼电噪声,并进行时域和频域的数据增强,将原始数据、时... 针对传统的脑电信号识别算法样本量较小、识别分类准确率较低的问题,提出了一种基于时频域数据增强的多尺度特征融合运动想象脑电信号分类算法。对原始信号进行独立主成分分析滤除眼电噪声,并进行时域和频域的数据增强,将原始数据、时域增强数据、频域增强数据三组数据分别进行多尺度多频带的共空间模式、功率谱密度以及小波包能量特征提取,合并特征并通过特征选择得到最佳特征组,训练支持向量机,由投票得出最终分类结果。在公开数据集BCI CompetitionⅣ-2a和OpenBMI上进行验证,结果表明提出的方法分类效果良好,分类准确率高于其他对比方法。 展开更多
关键词 运动想象 数据增强 共空间模式 支持向量机
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基于款式图像的汉服上襦规格尺寸提取
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作者 刘咏梅 杨欣蓓 张向辉 《毛纺科技》 北大核心 2025年第6期42-48,共7页
为研究基于款式图像的规格尺寸提取机制,针对较平面化特征的汉服上襦,将其款式图像转化为矢量款式图,编程提取矢量款式图的规格尺寸,并进行结构设计应用。首先搜集款式图像并分析款式特征,归纳上襦款式体系,获取5款典型款式上襦;然后处... 为研究基于款式图像的规格尺寸提取机制,针对较平面化特征的汉服上襦,将其款式图像转化为矢量款式图,编程提取矢量款式图的规格尺寸,并进行结构设计应用。首先搜集款式图像并分析款式特征,归纳上襦款式体系,获取5款典型款式上襦;然后处理款式图像,设计汉服上襦专用的160/84A通臂姿势人模,利用模块化绘制方法将款式图像转换成矢量款式图;分类设置5款典型款式的规格项目,编写相应的尺寸提取程序,运用程序提取矢量款式图的规格尺寸;最后采用结构设计及三维虚拟服装设计的方法,验证规格数据的样板生成效果。结果表明基于款式图像的规格尺寸提取方案具有可行性。 展开更多
关键词 款式图像 规格尺寸提取 汉服上襦 矢量款式图 样板生成
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基于PCA-GA-SVM的模式识别算法及应用
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作者 丁燕君 曲霖洁 《太原学院学报(自然科学版)》 2025年第3期66-71,共6页
针对SVM模式识别算法存在的模式识别准确率较低的问题,提出了一种基于PCA-GA-SVM的模式识别算法,并将其应用于滚动轴承模式识别中。该模式识别算法采用主成分分析,对数据进行降维,提取信息量大的主成分,确保所筛选元素之间线性无关。利... 针对SVM模式识别算法存在的模式识别准确率较低的问题,提出了一种基于PCA-GA-SVM的模式识别算法,并将其应用于滚动轴承模式识别中。该模式识别算法采用主成分分析,对数据进行降维,提取信息量大的主成分,确保所筛选元素之间线性无关。利用遗传算法,优化支持向量机的参数组合,提高SVM的模式识别性能。对比不同模式识别算法对滚动轴承运转模式的识别,结果表明,所提出的PCA-GA-SVM算法在滚动轴承故障模式识别中具有较高的准确率和稳定性,能够有效降低模式识别的复杂度,提升模式识别的性能。 展开更多
关键词 主成分分析 支持向量机 模式识别
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Progressive transductive learning pattern classification via single sphere
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作者 Xue Zhenxia Liu Sanyang Liu Wanli 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第3期643-650,共8页
In many machine learning problems, a large amount of data is available but only a few of them can be labeled easily. This provides a research branch to effectively combine unlabeled and labeled data to infer the label... In many machine learning problems, a large amount of data is available but only a few of them can be labeled easily. This provides a research branch to effectively combine unlabeled and labeled data to infer the labels of unlabeled ones, that is, to develop transductive learning. In this article, based on Pattern classification via single sphere (SSPC), which seeks a hypersphere to separate data with the maximum separation ratio, a progressive transductive pattern classification method via single sphere (PTSSPC) is proposed to construct the classifier using both the labeled and unlabeled data. PTSSPC utilize the additional information of the unlabeled samples and obtain better classification performance than SSPC when insufficient labeled data information is available. Experiment results show the algorithm can yields better performance. 展开更多
关键词 pattern recognition semi-supervised learning transductive learning CLASSIFICATION support vector machine support vector domain description.
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甜菜BvNAC40基因克隆、表达模式分析与载体构建
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作者 范梓奇 孙亚卿 +2 位作者 李宁宁 张少英 李国龙 《西北农林科技大学学报(自然科学版)》 北大核心 2025年第12期30-37,46,共9页
【目的】NAC转录因子在植物抵御逆境胁迫中作用显著。从抗旱甜菜品种‘HI0466’中克隆了NAC转录因子基因BvNAC40,分析其蛋白结构及干旱胁迫下的表达模式,为后续深入解析BvNAC40基因的抗旱功能及甜菜抗旱品种的选育提供理论依据。【方法... 【目的】NAC转录因子在植物抵御逆境胁迫中作用显著。从抗旱甜菜品种‘HI0466’中克隆了NAC转录因子基因BvNAC40,分析其蛋白结构及干旱胁迫下的表达模式,为后续深入解析BvNAC40基因的抗旱功能及甜菜抗旱品种的选育提供理论依据。【方法】利用PCR技术克隆BvNAC40基因,并通过生物信息学分析其蛋白结构,利用绿色荧光蛋白(GFP)标记技术进行亚细胞定位研究。利用RT-qPCR技术检测BvNAC40基因在干旱胁迫处理下的表达量。利用同源重组技术构建BvNAC40基因的过表达载体和基于烟草脆裂病毒的基因沉默载体。【结果】BvNAC40基因的CDS区序列全长1182 bp,编码393个氨基酸,属于NAC转录因子家族,C端存在跨膜结构域,亚细胞定位显示其主要位于细胞核中。在干旱胁迫处理下,BvNAC40基因在甜菜叶片和根中均显著上调表达。【结论】BvNAC40基因在甜菜抗旱过程中特异表达,后续可以通过转基因技术研究其功能。 展开更多
关键词 甜菜 NAC转录因子 干旱胁迫 表达模式 载体构建
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玉米ZmIMPα基因的生物信息学分析及其在盐胁迫下的表达模式分析 被引量:1
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作者 郭昭阳 殷宇航 +3 位作者 刘钰 高璇 宋希云 赵美爱 《山东农业科学》 北大核心 2025年第2期1-10,共10页
输入蛋白α(IMPα)是细胞质中蛋白质和RNA等物质进入细胞核的重要运输蛋白,在植物中发挥着重要作用。本研究对玉米IMPα基因进行鉴定及生物信息学分析,同时利用实时荧光定量PCR技术分析盐胁迫下ZmIMPα在不同玉米自交系中的相对表达量,... 输入蛋白α(IMPα)是细胞质中蛋白质和RNA等物质进入细胞核的重要运输蛋白,在植物中发挥着重要作用。本研究对玉米IMPα基因进行鉴定及生物信息学分析,同时利用实时荧光定量PCR技术分析盐胁迫下ZmIMPα在不同玉米自交系中的相对表达量,并进一步构建其原核过表达载体后转化大肠杆菌DH5α,通过分析菌株在盐胁迫下的生长情况对该基因的功能进行验证。结果表明,从玉米中鉴定出7个IMPα基因共15个转录本,其编码蛋白序列长度为297~625 aa,分子量32.5~64.0 kDa,等电点3.95~7.27,均定位在细胞质中,有10个蛋白还同时定位在细胞核中。系统进化树分析结果表明,除Zm00001eb001150_T001外,其余ZmIMPα可分为3个亚家族,与拟南芥的IMPα蛋白相似性较高。保守结构域分析发现IMPα家族属于SRP1超家族,启动子分析发现该家族基因含有激素响应元件和非生物胁迫相关响应元件,可能在植物生长和响应非生物胁迫方面发挥作用。盐胁迫下ZmIMPα基因在耐盐玉米材料中的表达量显著上升,而在盐敏感材料中表达量显著下降。原核表达分析结果显示,与空载菌株相比,含有重组质粒pET28a-ZmIMPα的菌株在0.6 mol/L和0.8 mol/L NaCl胁迫下的生长都受到了抑制,且受抑制程度随NaCl浓度上升而增大,推测ZmIMPα基因可能在玉米响应盐胁迫过程中呈负调控模式。本研究结果可为进一步深入探索输入蛋白家族基因在植物抗逆过程中的作用提供一定的理论参考。 展开更多
关键词 玉米 IMPα基因 生物信息学分析 盐胁迫 原核表达载体 表达模式
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