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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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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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大柳塔煤矿沿空留巷柔模砼墙支护阻力核定及失稳判据研究 被引量:4
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作者 李刚 刘航 +2 位作者 迟国铭 石占山 范永君 《工矿自动化》 北大核心 2025年第1期145-155,共11页
柔模砼墙沿空留巷工作面覆岩垮落结构与砼墙的稳定性是留巷成功与否的关键。以大柳塔煤矿52606工作面为研究对象,通过相似材料模拟实验发现在52605工作面和52606工作面回采结束后,砼墙上方覆岩垮落呈短悬臂梁结构,且砼墙侧垮落角均大于... 柔模砼墙沿空留巷工作面覆岩垮落结构与砼墙的稳定性是留巷成功与否的关键。以大柳塔煤矿52606工作面为研究对象,通过相似材料模拟实验发现在52605工作面和52606工作面回采结束后,砼墙上方覆岩垮落呈短悬臂梁结构,且砼墙侧垮落角均大于煤壁侧垮落角,二次采动后2个工作面裂隙贯通向地表发育,砼墙上方地面出现略微沉降。针对上述情况,通过分析覆岩垮落结构特征,确定了沿空巷道顶板第1次断裂位置位于采空区上方充填体一侧,第2次断裂位置位于采空区形成悬臂梁结构的岩层中靠近煤壁侧,并结合理论分析得到柔模砼墙沿空留巷应力分布特征。根据沿空巷道不同使用阶段门式支架是否撤出,提出留巷阶段砼墙的支护阻力采用分离岩块法计算,巷道复用阶段砼墙的支护阻力采用倾斜岩梁法计算;柔模砼墙的稳定性与安全系数有关,工作面回采过程中保证安全系数大于1,则砼墙不会发生失稳破坏。实例验证结果表明:该留巷工作面使用门式支架做临时支护时,为保证砼墙的安全系数大于2,需保证砼墙强度达到5.4 MPa以上;撤出门式支架后,断裂岩块及其覆岩载荷由砼墙承担,且采动引起的动载不断对砼墙产生影响,但砼墙的安全系数为3.9,砼墙仍相对稳定;砼墙应力虽然是不断变化的,但变化幅度都不大,均未出现应力急剧增大或减小的现象,这说明砼墙可有效支撑顶板,且砼墙一直处于稳定状态。 展开更多
关键词 沿空留巷 柔模砼墙 砼墙安全系数 门式支架 采动阶段 覆岩运移规律 支护阻力
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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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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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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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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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Reflections on the Guardianship and Support System of the Elderly Under the Background of an Aging Society
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作者 王丽萍 LI Xiang(译) 《The Journal of Human Rights》 2019年第4期422-436,共15页
China Is aging society poses new challenges to guardianship system in the General Rules of the Civil Law of the People s Republic of China.The General Provisions of the Civil Law adapts to the requirements of the time... China Is aging society poses new challenges to guardianship system in the General Rules of the Civil Law of the People s Republic of China.The General Provisions of the Civil Law adapts to the requirements of the times and makes some important amendments and supplements to the guardianship system,notably the scope of adults with civil disability or limited capacity for civil conduct is no longer limited to people with a mental illness.However,there remain many deficiencies in the regulations.Based on the framework provisions of the existing guardianship system of the General Provisions of Civil Law,in the compilation of the marrage and family provisions in the Civil Code,it is necessary to strengthen the protection of the rights and interests of the elderly in an aging society,further improve the elderly guardianship system,including changing the single pattern of the guardianship system and improving the"dual subject"pattern of adult guardianship and adult support system,expand the scope of protected subject of guardianship,and improve the existing system of intentional custody,adult guardianship system,and guardianship and supervision system. 展开更多
关键词 aging SOCIETY GUARDIANSHIP SYSTEM ADULT GUARDIANSHIP support SYSTEM "dual subject"protection pattern
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深部碎裂岩体巷道变形破坏机制与支护效应连续-非连续分析 被引量:1
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作者 张世瑞 江权 +3 位作者 邱士利 周小平 寇永渊 刘建坡 《采矿与岩层控制工程学报》 北大核心 2025年第1期82-93,共12页
金川二矿深部碎裂岩体具有“岩块强度高,岩体强度低”的显著特点,巷道围岩具有显著的大变形特征,导致喷锚网或衬砌等支护结构破坏频繁,严重威胁采矿生产安全。以该矿深部巷道现场工程为背景,首先,通过现场调查和实测确定该矿深部巷道围... 金川二矿深部碎裂岩体具有“岩块强度高,岩体强度低”的显著特点,巷道围岩具有显著的大变形特征,导致喷锚网或衬砌等支护结构破坏频繁,严重威胁采矿生产安全。以该矿深部巷道现场工程为背景,首先,通过现场调查和实测确定该矿深部巷道围岩具有典型层状、碎裂状和复合结构特征,冒落和底臌为典型的破坏形式;其次,结合室内试验和现场监测数据,基于连续-非连续数值模拟分析方法 (FDEM)提出一种可破Voronoi块体模型和离散裂隙网络模型模拟巷道开挖过程,捕获围岩损伤破裂特征;最后,结合实体单元和锚杆单元模拟支护结构响应,探讨深部碎裂岩体变形破坏机制和支护效应。研究结果表明,结构面间距和倾角显著影响应力释放区的位置和压力拱的形成,导致围岩变形各向异性和破裂非均匀性;锚杆、混凝土喷层+锚杆及U型钢拱架+锚杆3种支护结构对于限制围岩变形具有显著差异性,加入锚杆和衬砌能有效抑制冒落区,限制顶拱位移,但不能有效抑制底板隆起;超前注浆、加长锚杆和钢拱架是控制深部碎裂岩体巷道大变形的重要措施。研究结果可为深部碎裂岩体巷道变形控制与支护设计提供理论参考。 展开更多
关键词 碎裂岩体 大变形 深部巷道 连续-非连续分析 支护方式
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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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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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山东省大豆玉米带状复合种植机械化技术对比试验分析 被引量:7
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作者 刘科 徐婷 +4 位作者 康云友 刘婧 李登宇 刘刚毅 刘旭东 《农机化研究》 北大核心 2025年第8期167-174,共8页
我国常年需求大豆1.2亿t、玉米2.5亿t,2020年和2021年进口大豆均突破1亿t,量价齐升,进口数量占需求量的80%以上。为了应对国际贸易摩擦带来的大豆和玉米短缺风险,扩种大豆油料是党中央部署的重大政治任务,在保障国家粮油安全方面具有重... 我国常年需求大豆1.2亿t、玉米2.5亿t,2020年和2021年进口大豆均突破1亿t,量价齐升,进口数量占需求量的80%以上。为了应对国际贸易摩擦带来的大豆和玉米短缺风险,扩种大豆油料是党中央部署的重大政治任务,在保障国家粮油安全方面具有重要的战略意义。在土地资源有限的条件下,大豆玉米带状复合种植机械化技术能够保证玉米基本不减产,增收一季大豆,破解大豆玉米争地难题,提升国家粮油综合生产能力。由于地域规模、光热资源、机械配套等因素的限制,不同地区大豆玉米带状复合种植模式多样,成本、产量、效益等差异较大,影响技术的推广。为探寻适合山东省的大豆玉米带状复合种植机械化模式,筛选适宜机具,提高农民综合效益,研究选取山东省禹城市为试验点,通过调研,选取种植最多的4+2、4+3、6+3、6+4等4种复合种植模式,围绕种、管、收3个环节栽培要点和机械选配,从出苗率、产量、机收损失率、产出效益和作业成本等方面进行对比分析,筛选适宜山东省大豆玉米带状复合种植的技术模式和机具配套方案,为大面积推广提供技术支撑。 展开更多
关键词 大豆玉米复合种植 种植模式 配套机具 山东省
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不同种植模式下智能化灌溉技术需求分析与优化策略
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作者 李世柱 黄文明 《农业工程》 2025年第4期132-137,共6页
阐明智能化灌溉技术应用目的与意义,介绍智能化灌溉技术体系。通过资料查阅、电话访谈等多种方式相结合的方法,分析不同种植模式下智能化灌溉技术需求,并且提出针对性优化策略。旨在为智能化灌溉技术发展提供参考借鉴。
关键词 种植模式 智能化灌溉技术 配套技术 需求分析 优化策略
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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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基于计算机视觉与机器学习的结晶器漏钢预报模型 被引量:1
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作者 王砚宇 程永辉 +5 位作者 朱国强 陈柏宇 张立辉 王齐灿 姚曼 王旭东 《钢铁》 北大核心 2025年第6期103-112,共10页
连铸生产过程中可能会发生许多异常情况,其中漏钢事故是连铸生产中最严重的事故之一。漏钢发生前的典型征兆之一是在铜板局部上形成的呈“V”形扩展的黏结区域,需借助稳定可靠的方法对其进行检测和预报。利用计算机视觉技术,将结晶器铜... 连铸生产过程中可能会发生许多异常情况,其中漏钢事故是连铸生产中最严重的事故之一。漏钢发生前的典型征兆之一是在铜板局部上形成的呈“V”形扩展的黏结区域,需借助稳定可靠的方法对其进行检测和预报。利用计算机视觉技术,将结晶器铜板表面采集到的热电偶温度信号及计算得出的温度速率,与颜色空间建立映射关系,并以二维平面热像图的形式来表征异常黏结区域。通过提取图中黏结区域的动态与静态特征,构建出代表黏结区域的十维特征向量。基于某钢厂的漏钢统计报表,建立了黏结区域特征向量样本库。同时,采用支持向量机(support vector machine,SVM)和随机森林(random forest,RF)这2种机器学习模型,对真伪黏结区域特征进行学习和识别。测试结果表明,相较于随机森林模型,支持向量机模型能够更有效地识别出黏结漏钢的异常温度模式,随机森林模型在预测结果中存在2例漏报,而支持向量机模型的漏钢报出率可达到100%,并且将误报率控制在10%以下(9.93%),在几何平均数Gmean分数(0.95)和模型AUC(0.98)(受试者工作特征曲线下方的面积)等指标方面,支持向量机模型也显著优于随机森林模型,这表明该模型能够满足漏钢预报任务的要求。基于上述结果,建立了基于计算机视觉与机器学习的结晶器漏钢预报模型,为连铸生产中基于数据驱动的过程异常检测和预报技术提供了参考。 展开更多
关键词 漏钢预报 “V”形黏结 计算机视觉 特征提取 支持向量机 随机森林 模式识别 连铸
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