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Comparison of debris flow susceptibility assessment methods:support vector machine,particle swarm optimization,and feature selection techniques 被引量:1
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作者 ZHAO Haijun WEI Aihua +3 位作者 MA Fengshan DAI Fenggang JIANG Yongbing LI Hui 《Journal of Mountain Science》 SCIE CSCD 2024年第2期397-412,共16页
The selection of important factors in machine learning-based susceptibility assessments is crucial to obtain reliable susceptibility results.In this study,metaheuristic optimization and feature selection techniques we... The selection of important factors in machine learning-based susceptibility assessments is crucial to obtain reliable susceptibility results.In this study,metaheuristic optimization and feature selection techniques were applied to identify the most important input parameters for mapping debris flow susceptibility in the southern mountain area of Chengde City in Hebei Province,China,by using machine learning algorithms.In total,133 historical debris flow records and 16 related factors were selected.The support vector machine(SVM)was first used as the base classifier,and then a hybrid model was introduced by a two-step process.First,the particle swarm optimization(PSO)algorithm was employed to select the SVM model hyperparameters.Second,two feature selection algorithms,namely principal component analysis(PCA)and PSO,were integrated into the PSO-based SVM model,which generated the PCA-PSO-SVM and FS-PSO-SVM models,respectively.Three statistical metrics(accuracy,recall,and specificity)and the area under the receiver operating characteristic curve(AUC)were employed to evaluate and validate the performance of the models.The results indicated that the feature selection-based models exhibited the best performance,followed by the PSO-based SVM and SVM models.Moreover,the performance of the FS-PSO-SVM model was better than that of the PCA-PSO-SVM model,showing the highest AUC,accuracy,recall,and specificity values in both the training and testing processes.It was found that the selection of optimal features is crucial to improving the reliability of debris flow susceptibility assessment results.Moreover,the PSO algorithm was found to be not only an effective tool for hyperparameter optimization,but also a useful feature selection algorithm to improve prediction accuracies of debris flow susceptibility by using machine learning algorithms.The high and very high debris flow susceptibility zone appropriately covers 38.01%of the study area,where debris flow may occur under intensive human activities and heavy rainfall events. 展开更多
关键词 Chengde feature selection Support vector machine Particle swarm optimization Principal component analysis Debris flow susceptibility
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Feature Extraction of Stored-grain Insects Based on Ant Colony Optimization and Support Vector Machine Algorithm 被引量:1
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作者 胡玉霞 张红涛 +1 位作者 罗康 张恒源 《Agricultural Science & Technology》 CAS 2012年第2期457-459,共3页
[Objective] The aim was to study the feature extraction of stored-grain insects based on ant colony optimization and support vector machine algorithm, and to explore the feasibility of the feature extraction of stored... [Objective] The aim was to study the feature extraction of stored-grain insects based on ant colony optimization and support vector machine algorithm, and to explore the feasibility of the feature extraction of stored-grain insects. [Method] Through the analysis of feature extraction in the image recognition of the stored-grain insects, the recognition accuracy of the cross-validation training model in support vector machine (SVM) algorithm was taken as an important factor of the evaluation principle of feature extraction of stored-grain insects. The ant colony optimization (ACO) algorithm was applied to the automatic feature extraction of stored-grain insects. [Result] The algorithm extracted the optimal feature subspace of seven features from the 17 morphological features, including area and perimeter. The ninety image samples of the stored-grain insects were automatically recognized by the optimized SVM classifier, and the recognition accuracy was over 95%. [Conclusion] The experiment shows that the application of ant colony optimization to the feature extraction of grain insects is practical and feasible. 展开更多
关键词 Stored-grain insects Ant colony optimization algorithm Support vector machine feature extraction RECOGNITION
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Accelerated Recursive Feature Elimination Based on Support Vector Machine for Key Variable Identification 被引量:4
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作者 毛勇 皮道映 +1 位作者 刘育明 孙优贤 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2006年第1期65-72,共8页
Key variable identification for classifications is related to many trouble-shooting problems in process indus-tries. Recursive feature elimination based on support vector machine (SVM-RFE) has been proposed recently i... Key variable identification for classifications is related to many trouble-shooting problems in process indus-tries. Recursive feature elimination based on support vector machine (SVM-RFE) has been proposed recently in applica-tion for feature selection in cancer diagnosis. In this paper, SVM-RFE is used to the key variable selection in fault diag-nosis, and an accelerated SVM-RFE procedure based on heuristic criterion is proposed. The data from Tennessee East-man process (TEP) simulator is used to evaluate the effectiveness of the key variable selection using accelerated SVM-RFE (A-SVM-RFE). A-SVM-RFE integrates computational rate and algorithm effectiveness into a consistent framework. It not only can correctly identify the key variables, but also has very good computational rate. In comparison with contribution charts combined with principal component aralysis (PCA) and other two SVM-RFE algorithms, A-SVM-RFE performs better. It is more fitting for industrial application. 展开更多
关键词 variable selection support vector machine recursive feature elimination fault diagnosis
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Evolutionary Computation Based Optimization of Image Zernike Moments Shape Feature Vector 被引量:1
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作者 LIU Maofu HU Hujun +2 位作者 ZHONG Ming HE Yanxiang HE Fazhi 《Wuhan University Journal of Natural Sciences》 CAS 2008年第2期153-158,共6页
The image shape feature can be described by the image Zernike moments. In this paper, we points out the problem that the high dimension image Zernike moments shape feature vector can describe more detail of the origin... The image shape feature can be described by the image Zernike moments. In this paper, we points out the problem that the high dimension image Zernike moments shape feature vector can describe more detail of the original image but has too many elements making trouble for the next image analysis phases. Then the low dimension image Zernike moments shape feature vector should be improved and optimized to describe more detail of the original image. So the optimization algorithm based on evolutionary computation is designed and implemented in this paper to solve this problem. The experimental results demonstrate the feasibility of the optimization algorithm. 展开更多
关键词 Zernike moment image Zernike moments shape feature vector image reconstruction evolutionary computation
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Feature Selection by Merging Sequential Bidirectional Search into Relevance Vector Machine in Condition Monitoring
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作者 ZHANG Kui DONG Yu BALL Andrew 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2015年第6期1248-1253,共6页
For more accurate fault detection and diagnosis, there is an increasing trend to use a large number of sensors and to collect data at high frequency. This inevitably produces large-scale data and causes difficulties i... For more accurate fault detection and diagnosis, there is an increasing trend to use a large number of sensors and to collect data at high frequency. This inevitably produces large-scale data and causes difficulties in fault classification. Actually, the classification methods are simply intractable when applied to high-dimensional condition monitoring data. In order to solve the problem, engineers have to resort to complicated feature extraction methods to reduce the dimensionality of data. However, the features transformed by the methods cannot be understood by the engineers due to a loss of the original engineering meaning. In this paper, other forms of dimensionality reduction technique(feature selection methods) are employed to identify machinery condition, based only on frequency spectrum data. Feature selection methods are usually divided into three main types: filter, wrapper and embedded methods. Most studies are mainly focused on the first two types, whilst the development and application of the embedded feature selection methods are very limited. This paper attempts to explore a novel embedded method. The method is formed by merging a sequential bidirectional search algorithm into scale parameters tuning within a kernel function in the relevance vector machine. To demonstrate the potential for applying the method to machinery fault diagnosis, the method is implemented to rolling bearing experimental data. The results obtained by using the method are consistent with the theoretical interpretation, proving that this algorithm has important engineering significance in revealing the correlation between the faults and relevant frequency features. The proposed method is a theoretical extension of relevance vector machine, and provides an effective solution to detect the fault-related frequency components with high efficiency. 展开更多
关键词 feature selection relevance vector machine sequential bidirectional search fault diagnosis
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Fault depth estimation using support vector classifier and features selection
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作者 Mohammad Ehsan Hekmatian Vahid E. Ardestani +2 位作者 Mohammad Ali Riahi Ayyub Memar Koucheh Bagh Jalal Amini 《Applied Geophysics》 SCIE CSCD 2013年第1期88-96,119,共10页
Depth estimation of subsurface faults is one of the problems in gravity interpretation. We tried using the support vector classifier (SVC) method in the estimation. Using forward and nonlinear inverse techniques, de... Depth estimation of subsurface faults is one of the problems in gravity interpretation. We tried using the support vector classifier (SVC) method in the estimation. Using forward and nonlinear inverse techniques, detecting the depth of subsurface faults with related error is possible but it is necessary to have an initial guess for the depth and this initial guess usually comes from non-gravity data. We introduce SVC in this paper as one of the tools for estimating the depth of subsurface faults using gravity data. We can suppose that each subsurface fault depth is a class and that SVC is a classification algorithm. To better use the SVC algorithm, we select proper depth estimation features using a proper features selection (FS) algorithm. In this research, we produce a training set consisting of synthetic gravity profiles created by subsurface faults at different depths to train the SVC code to estimate the depth of real subsurface faults. Then we test our trained SVC code by a testing set consisting of other synthetic gravity profiles created by subsurface faults at different depths. We also tested our trained SVC code using real data. 展开更多
关键词 depth estimation subsurface fault support vector classifier feature featuresselection
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MRMR Based Feature Vector Design for Efficient Citrus Disease Detection
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作者 Bobbinpreet Sultan Aljahdali +4 位作者 Tripti Sharma Bhawna Goyal Ayush Dogra Shubham Mahajan Amit Kant Pandit 《Computers, Materials & Continua》 SCIE EI 2022年第9期4771-4787,共17页
In recent times,the images and videos have emerged as one of the most important information source depicting the real time scenarios.Digital images nowadays serve as input for many applications and replacing the manua... In recent times,the images and videos have emerged as one of the most important information source depicting the real time scenarios.Digital images nowadays serve as input for many applications and replacing the manual methods due to their capabilities of 3D scene representation in 2D plane.The capabilities of digital images along with utilization of machine learning methodologies are showing promising accuracies in many applications of prediction and pattern recognition.One of the application fields pertains to detection of diseases occurring in the plants,which are destroying the widespread fields.Traditionally the disease detection process was done by a domain expert using manual examination and laboratory tests.This is a tedious and time consuming process and does not suffice the accuracy levels.This creates a room for the research in developing automation based methods where the images captured through sensors and cameras will be used for detection of disease and control its spreading.The digital images captured from the field’s forms the dataset which trains the machine learning models to predict the nature of the disease.The accuracy of these models is greatly affected by the amount of noise and ailments present in the input images,appropriate segmentation methodology,feature vector development and the choice of machine learning algorithm.To ensure the high rated performance of the designed system the research is moving in a direction to fine tune each and every stage separately considering their dependencies on subsequent stages.Therefore the most optimum solution can be obtained by considering the image processing methodologies for improving the quality of image and then applying statistical methods for feature extraction and selection.The training vector thus developed is capable of presenting the relationship between the feature values and the target class.In this article,a highly accurate system model for detecting the diseases occurring in citrus fruits using a hybrid feature development approach is proposed.The overall improvement in terms of accuracy is measured and depicted. 展开更多
关键词 Citrus diseases CLASSIFICATION feature vector design plant disease detection redundancy reduction
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Automatic detection method of bladder tumor cells based on color and shape features
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作者 Zitong Zhao Yanbo Wang +6 位作者 Jiaqi Chen Mingjia Wang Shulong Feng Jin Yang Nan Song Jinyu Wang Ci Sun 《Journal of Innovative Optical Health Sciences》 SCIE EI CSCD 2024年第6期1-13,共13页
Bladder urothelial carcinoma is the most common malignant tumor disease in urinary system,and its incidence rate ranks ninth in the world.In recent years,the continuous development of hyperspectral imaging technology ... Bladder urothelial carcinoma is the most common malignant tumor disease in urinary system,and its incidence rate ranks ninth in the world.In recent years,the continuous development of hyperspectral imaging technology has provided a new tool for the auxiliary diagnosis of bladder cancer.In this study,based on microscopic hyperspectral data,an automatic detection algorithm of bladder tumor cells combining color features and shape features is proposed.Support vector machine(SVM)is used to build classification models and compare the classification performance of spectral feature,spectral and shape fusion feature,and the fusion feature proposed in this paper on the same classifier.The results show that the sensitivity,specificity,and accuracy of our classification algorithm based on shape and color fusion features are 0.952,0.897,and 0.920,respectively,which are better than the classification algorithm only using spectral features.Therefore,this study can effectively extract the cell features of bladder urothelial carcinoma smear,thus achieving automatic,real-time,and noninvasive detection of bladder tumor cells,and then helping doctors improve the efficiency of pathological diagnosis of bladder urothelial cancer,and providing a reliable basis for doctors to choose treatment plans and judge the prognosis of the disease. 展开更多
关键词 Bladder tumor cells microscopic hyperspectral fusion feature support vector machine automatic detection.
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Person Authentication Using a New Feature Vector of the Brain Wave
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作者 Isao Nakanishi Sadanao Baba Chisei Miyamoto Shignag Li 《通讯和计算机(中英文版)》 2012年第1期101-105,共5页
关键词 身份验证 特征向量 脑电波 生物识别技术 生物认证 光计算 用户管理 验证实验
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Deep learning CNN-APSO-LSSVM hybrid fusion model for feature optimization and gas-bearing prediction
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作者 Jiu-Qiang Yang Nian-Tian Lin +3 位作者 Kai Zhang Yan Cui Chao Fu Dong Zhang 《Petroleum Science》 SCIE EI CAS CSCD 2024年第4期2329-2344,共16页
Conventional machine learning(CML)methods have been successfully applied for gas reservoir prediction.Their prediction accuracy largely depends on the quality of the sample data;therefore,feature optimization of the i... Conventional machine learning(CML)methods have been successfully applied for gas reservoir prediction.Their prediction accuracy largely depends on the quality of the sample data;therefore,feature optimization of the input samples is particularly important.Commonly used feature optimization methods increase the interpretability of gas reservoirs;however,their steps are cumbersome,and the selected features cannot sufficiently guide CML models to mine the intrinsic features of sample data efficiently.In contrast to CML methods,deep learning(DL)methods can directly extract the important features of targets from raw data.Therefore,this study proposes a feature optimization and gas-bearing prediction method based on a hybrid fusion model that combines a convolutional neural network(CNN)and an adaptive particle swarm optimization-least squares support vector machine(APSO-LSSVM).This model adopts an end-to-end algorithm structure to directly extract features from sensitive multicomponent seismic attributes,considerably simplifying the feature optimization.A CNN was used for feature optimization to highlight sensitive gas reservoir information.APSO-LSSVM was used to fully learn the relationship between the features extracted by the CNN to obtain the prediction results.The constructed hybrid fusion model improves gas-bearing prediction accuracy through two processes of feature optimization and intelligent prediction,giving full play to the advantages of DL and CML methods.The prediction results obtained are better than those of a single CNN model or APSO-LSSVM model.In the feature optimization process of multicomponent seismic attribute data,CNN has demonstrated better gas reservoir feature extraction capabilities than commonly used attribute optimization methods.In the prediction process,the APSO-LSSVM model can learn the gas reservoir characteristics better than the LSSVM model and has a higher prediction accuracy.The constructed CNN-APSO-LSSVM model had lower errors and a better fit on the test dataset than the other individual models.This method proves the effectiveness of DL technology for the feature extraction of gas reservoirs and provides a feasible way to combine DL and CML technologies to predict gas reservoirs. 展开更多
关键词 Multicomponent seismic data Deep learning Adaptive particle swarm optimization Convolutional neural network Least squares support vector machine feature optimization Gas-bearing distribution prediction
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纤维肌痛综合征生物标记物的筛选及免疫细胞浸润分析
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作者 刘雅妮 杨静欢 +5 位作者 陆慧慧 易玉芳 李智翔 欧阳福 吴璟莉 魏兵 《中国组织工程研究》 CAS 北大核心 2025年第5期1091-1100,共10页
背景:纤维肌痛综合征作为常见风湿病,其发病与中枢敏化及免疫异常有关,但具体过程尚未阐明,缺乏特异性诊断标志物,不断探索该病的发病机制具有重要的临床意义。目的:基于加权基因共表达网络分析(WGCNA)等生物信息学方法和机器学习算法... 背景:纤维肌痛综合征作为常见风湿病,其发病与中枢敏化及免疫异常有关,但具体过程尚未阐明,缺乏特异性诊断标志物,不断探索该病的发病机制具有重要的临床意义。目的:基于加权基因共表达网络分析(WGCNA)等生物信息学方法和机器学习算法筛选纤维肌痛综合征潜在的诊断相关标志基因,并分析其免疫细胞浸润特征。方法:对来自基因表达综合数据库(GEO)的纤维肌痛综合征数据集转录谱进行差异分析和WGCNA分析,整合筛选出差异共表达基因,进一步采用机器学习套索回归(LASSO)算法、支持向量机递归特征消除(SVM-RFE)机器学习算法来识别核心生物标志物,并绘制受试者工作特征(ROC)曲线以评估诊断价值。最后,采用单样本基因集富集分析(ssGSEA)和基因集富集分析(GSEA)评估纤维肌痛综合征的免疫细胞浸润情况及通路富集。结果与结论:①对GSE67311数据集按照log2|(FC)|>0,P<0.05的条件进行差异分析后获得8个下调的差异表达基因;进行WGCNA分析后获得正相关性最高(r=0.22,P=0.04)的模块(MEdarkviolet)内含基因497个,负相关性最高(r=-0.41,P=6×10-5)的模块(MEsalmon2)内含基因19个;将差异表达基因与WGCNA的2个高相关性模块基因取交集,获得7个基因。②对上述7个基因进行LASSO回归算法筛选出4个基因,进行SVM-RFE机器学习算法筛选出5个基因,两者取交集后确定了3个核心基因,分别为重组1号染色体开放阅读框150蛋白(germinal center associated signaling and motility like,GCSAML)、整合素β8(Integrin beta-8,ITGB8)和羧肽酶A3(carboxypeptidase A3,CPA3);绘制3个核心基因的ROC曲线下面积分别为0.744,0.739,0.734,提示均具有很好的诊断价值,可作为纤维肌痛综合征的生物标志物。③免疫浸润分析结果显示,与对照组相比纤维肌痛综合征患者记忆B细胞、CD56 bright NK细胞和肥大细胞显著下调(P<0.05),且与上述3个生物标志物显著正相关(P<0.05)。④富集分析结果提示,纤维肌痛综合征的富集途径包括9条,主要与嗅觉传导、神经活性配体-受体相互作用及感染等通路密切相关。⑤上述结果显示,纤维肌痛综合征的发生发展与多基因参与、免疫调节异常及多个通路失调有关,但这些基因与免疫细胞之间的相互作用,以及它们与各通路之间的关系尚需进一步研究。 展开更多
关键词 纤维肌痛综合征 生物信息学 机器学习 免疫浸润 加权基因共表达网络分析 套索回归 支持向量机递归特征消除算法 单样本基因集富集分析 基因集富集分析
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Phishing detection method based on URL features 被引量:2
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作者 曹玖新 董丹 +1 位作者 毛波 王田峰 《Journal of Southeast University(English Edition)》 EI CAS 2013年第2期134-138,共5页
In order to effectively detect malicious phishing behaviors, a phishing detection method based on the uniform resource locator (URL) features is proposed. First, the method compares the phishing URLs with legal ones... In order to effectively detect malicious phishing behaviors, a phishing detection method based on the uniform resource locator (URL) features is proposed. First, the method compares the phishing URLs with legal ones to extract the features of phishing URLs. Then a machine learning algorithm is applied to obtain the URL classification model from the sample data set training. In order to adapt to the change of a phishing URL, the classification model should be constantly updated according to the new samples. So, an incremental learning algorithm based on the feedback of the original sample data set is designed. The experiments verify that the combination of the URL features extracted in this paper and the support vector machine (SVM) classification algorithm can achieve a high phishing detection accuracy, and the incremental learning algorithm is also effective. 展开更多
关键词 uniform resource locator (URL) features phishingdetection support vector machine incremental learning
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基于语音信号时频特征融合的帕金森病检测方法
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作者 王晨哲 季薇 +1 位作者 郑慧芬 李云 《郑州大学学报(理学版)》 CAS 北大核心 2025年第1期53-60,共8页
发音障碍是帕金森病的早期症状之一。近年来,基于语音信号的帕金森病检测的研究大多采用梅尔刻度下的相关语音特征与深度神经网络模型相结合的方法。然而,现有的模型无法充分关注语音信号的全局时序信息,且梅尔刻度特征在准确表征帕金... 发音障碍是帕金森病的早期症状之一。近年来,基于语音信号的帕金森病检测的研究大多采用梅尔刻度下的相关语音特征与深度神经网络模型相结合的方法。然而,现有的模型无法充分关注语音信号的全局时序信息,且梅尔刻度特征在准确表征帕金森病的病理信息方面效果有限。为此,提出了一种基于语音时频特征融合的帕金森病检测方法。首先,提取语音的梅尔频率倒谱系数,并将其作为模型的输入。接着,在已有的S-vectors模型中引入Conformer编码器模块,以提取语音的时域全局特征。最后,将与帕金森病语音检测相关的频域全局特征嵌入时域特征中进行时频信息融合,以实现帕金森病语音检测。在公开帕金森病语音数据集和自采语音数据集上验证了方法的有效性。 展开更多
关键词 帕金森病 梅尔频率倒谱系数 S-vectors CONFORMER 时频特征融合
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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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FVS-MSVM方法在机器人建模与辨识中的应用 被引量:2
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作者 李军 张观东 《振动与冲击》 EI CSCD 北大核心 2018年第20期67-74,共8页
针对强耦合、高度非线性的机器人辨识问题,提出一种基于特征向量选择(FVS)的多输出支持向量机(MSVM)方法。该方法由核技术对映射至特征空间的输入数据,按照几何上的考虑提取相关的数据向量,形成特征空间的一个基底,所选择的数据向量定... 针对强耦合、高度非线性的机器人辨识问题,提出一种基于特征向量选择(FVS)的多输出支持向量机(MSVM)方法。该方法由核技术对映射至特征空间的输入数据,按照几何上的考虑提取相关的数据向量,形成特征空间的一个基底,所选择的数据向量定义为特征子空间。将数据投影至该子空间上,基于MSVM方法建立辨识模型,MSVM方法保持了在ε不敏感损失函数下具有紧凑与稀疏解的优点。为验证FVS-MSVM方法的有效性,将其应用于液压驱动机器人的油压辨识、PUMA 560工业机器人逆向运动学辨识、SARCOS仿生机器人逆向动力学建模中。在同等条件下,将FVS-MSVM方法与SVM、KPCA-MSVM及FVS-线性回归(LR)等方法进行比较。实验结果表明,FVS-MSVM方法不仅能够减小计算复杂度,而且具有很好的建模与辨识精度,模型的推广性好。 展开更多
关键词 特征向量 数据选择 支持向量机 机器人 建模 辨识
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基于机器学习的农田土壤抗剪强度参数检测方法研究
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作者 于艳艳 朱龙图 刘鹤 《农机化研究》 北大核心 2025年第1期7-15,共9页
土壤抗剪强度参数包括粘聚力和内摩擦角,是评价土壤侵蚀敏感性和反映耕层耕作性能的重要指标。为实现农田土壤抗剪切强度参数的快速检测,提出了一种基于机器学习的土壤抗剪切强度参数检测方法。以STM32单片机为核心处理器,采用圆锥杆、... 土壤抗剪强度参数包括粘聚力和内摩擦角,是评价土壤侵蚀敏感性和反映耕层耕作性能的重要指标。为实现农田土壤抗剪切强度参数的快速检测,提出了一种基于机器学习的土壤抗剪切强度参数检测方法。以STM32单片机为核心处理器,采用圆锥杆、滚珠丝杆滑台、三角支架等构建土壤数据采集装置,利用DYMH-103柱式压力传感器和FlexiForce薄膜传感器分别检测圆锥杆贯入土壤的锥尖阻力和锥侧压力,采用CSF11土壤水分传感器获取土壤含水率信息,通过多传感器数据特征向量提取构建建模数据集。数据集相关性分析结果表明:土壤抗剪强度参数与锥尖阻力、锥侧压力和土壤含水率之间具有明显相关性。利用蒙特卡罗交叉验证(Monte Carlo Cross Validation,MCCV)剔除了数据集中的4个异常样本;同时,提出了一种ELM-PLSR组合建模算法,以决定系数R^(2)和RPD为评价指标,对比评估了ELM、PLSR和ELM-PLSR 3种不同机器学习模型,结果表明:ELM-PLSR模型预测性能优于ELM模型和PLSR模型;检测粘聚力时,对应的R^(2)、RPD分别为0.919和3.475;检测内摩擦角时,对应的R 2和RPD分别为0.910和3.304。研究结果可为土壤抗剪强度参数快速测量提供参考。 展开更多
关键词 机器学习 土壤抗剪强度 多传感器 特征向量 预测模型
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Novel feature fusion method for speech emotion recognition based on multiple kernel learning
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作者 金赟 宋鹏 +1 位作者 郑文明 赵力 《Journal of Southeast University(English Edition)》 EI CAS 2013年第2期129-133,共5页
In order to improve the performance of speech emotion recognition, a novel feature fusion method is proposed. Based on the global features, the local information of different kinds of features is utilized. Both the gl... In order to improve the performance of speech emotion recognition, a novel feature fusion method is proposed. Based on the global features, the local information of different kinds of features is utilized. Both the global and the local features are combined together. Moreover, the multiple kernel learning method is adopted. The global features and each kind of local feature are respectively associated with a kernel, and all these kernels are added together with different weights to obtain a mixed kernel for nonlinear mapping. In the reproducing kernel Hilbert space, different kinds of emotional features can be easily classified. In the experiments, the popular Berlin dataset is used, and the optimal parameters of the global and the local kernels are determined by cross-validation. After computing using multiple kernel learning, the weights of all the kernels are obtained, which shows that the formant and intensity features play a key role in speech emotion recognition. The classification results show that the recognition rate is 78. 74% by using the global kernel, and it is 81.10% by using the proposed method, which demonstrates the effectiveness of the proposed method. 展开更多
关键词 speech emotion recognition multiple kemellearning feature fusion support vector machine
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基于小波去噪的FVS-KPCA故障检测方法 被引量:3
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作者 赵小强 王新明 《化工自动化及仪表》 CAS 北大核心 2010年第1期20-24,共5页
对于复杂非线性系统,实际得到的数据不可避免地带有噪声、随机干扰,而传统的核主元分析(KP-CA)方法应用于大样本集的故障检测,要计算核矩阵K很困难。为此,提出一种小波去噪与特征矢量选择-核主元分析(FVS-KPCA)相结合的故障检测方法,首... 对于复杂非线性系统,实际得到的数据不可避免地带有噪声、随机干扰,而传统的核主元分析(KP-CA)方法应用于大样本集的故障检测,要计算核矩阵K很困难。为此,提出一种小波去噪与特征矢量选择-核主元分析(FVS-KPCA)相结合的故障检测方法,首先对数据进行小波去噪,再采用特征矢量选择(FVS)与KPCA结合的方法能有效降低故障检测计算的复杂性。把上述方法应用到Tennessee Eastman(TE)化工过程,仿真结果表明该方法能有效地提高故障检测的速度。 展开更多
关键词 故障检测 小波去噪 核主元分析 特征矢量选择 TE过程
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抗汉滩病毒单抗3G1 scFv植物表达载体的构建 被引量:1
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作者 罗雯 张九东 +3 位作者 白文涛 吴兴安 胡刚 张芳琳 《西安联合大学学报》 2004年第5期5-7,共3页
利用PCR方法,从含有3G1scFv基因的重组质粒中扩增出抗体基因,并使基因两端携带合适的限制性酶切位点.将其克隆入植物表达载体pBI121,构建获得3G1scFv pBI121重组质粒.酶切鉴定及测序结果均证明重组质粒构建成功.将重组植物表达载体转入... 利用PCR方法,从含有3G1scFv基因的重组质粒中扩增出抗体基因,并使基因两端携带合适的限制性酶切位点.将其克隆入植物表达载体pBI121,构建获得3G1scFv pBI121重组质粒.酶切鉴定及测序结果均证明重组质粒构建成功.将重组植物表达载体转入农杆菌LBA4404,为进一步构建转基因植物的研究奠定了基础. 展开更多
关键词 汉滩病毒 单链抗体 植物表达载体
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基于FVE法的FDA-MIMO雷达主瓣密集假目标干扰抑制 被引量:5
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作者 陈浩 李荣锋 +1 位作者 戴凌燕 张昭建 《空军预警学院学报》 2018年第6期397-401,406,共6页
针对频率分集多输入多输出(FDA-MIMO)雷达在目标导向矢量失配、训练数据包含期望信号的情况下,主瓣密集假目标干扰抑制性能急剧下降的问题,根据FDA-MIMO信号模型,给出了FDA-MIMO雷达密集假目标干扰抑制机理,提出了一种基于特征向量剔除... 针对频率分集多输入多输出(FDA-MIMO)雷达在目标导向矢量失配、训练数据包含期望信号的情况下,主瓣密集假目标干扰抑制性能急剧下降的问题,根据FDA-MIMO信号模型,给出了FDA-MIMO雷达密集假目标干扰抑制机理,提出了一种基于特征向量剔除法(FVE)的干扰抑制方法.仿真结果表明,与特征空间投影(ESB)方法相比,该方法在低信噪比和低快拍的条件下仍能输出较高的信干噪比,提升了主瓣干扰的抑制性能. 展开更多
关键词 频率分集多输入多输出 特征向量剔除 主瓣密集假目标干扰抑制 输出信干噪比
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