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Decision tree support vector machine based on genetic algorithm for multi-class classification 被引量:17
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作者 Huanhuan Chen Qiang Wang Yi Shen 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2011年第2期322-326,共5页
To solve the multi-class fault diagnosis tasks, decision tree support vector machine (DTSVM), which combines SVM and decision tree using the concept of dichotomy, is proposed. Since the classification performance of... To solve the multi-class fault diagnosis tasks, decision tree support vector machine (DTSVM), which combines SVM and decision tree using the concept of dichotomy, is proposed. Since the classification performance of DTSVM highly depends on its structure, to cluster the multi-classes with maximum distance between the clustering centers of the two sub-classes, genetic algorithm is introduced into the formation of decision tree, so that the most separable classes would be separated at each node of decisions tree. Numerical simulations conducted on three datasets compared with "one-against-all" and "one-against-one" demonstrate the proposed method has better performance and higher generalization ability than the two conventional methods. 展开更多
关键词 support vector machine (SVM) decision tree GENETICALGORITHM classification.
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Use of Discrete Wavelet Features and Support Vector Machine for Fault Diagnosis of Face Milling Tool 被引量:4
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作者 C.K.Madhusudana N.Gangadhar +1 位作者 Hemantha Kumar S.Narendranath 《Structural Durability & Health Monitoring》 EI 2018年第2期111-127,共17页
This paper presents the fault diagnosis of face milling tool based on machine learning approach.While machining,spindle vibration signals in feed direction under healthy and faulty conditions of the milling tool are a... This paper presents the fault diagnosis of face milling tool based on machine learning approach.While machining,spindle vibration signals in feed direction under healthy and faulty conditions of the milling tool are acquired.A set of discrete wavelet features is extracted from the vibration signals using discrete wavelet transform(DWT)technique.The decision tree technique is used to select significant features out of all extracted wavelet features.C-support vector classification(C-SVC)andν-support vector classification(ν-SVC)models with different kernel functions of support vector machine(SVM)are used to study and classify the tool condition based on selected features.From the results obtained,C-SVC is the best model thanν-SVC and it can be able to give 94.5%classification accuracy for face milling of special steel alloy 42CrMo4. 展开更多
关键词 Fault diagnosis face milling decision tree discrete wavelet transform support vector machine
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Credit Card Fraud Detection Using Weighted Support Vector Machine 被引量:3
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作者 Dongfang Zhang Basu Bhandari Dennis Black 《Applied Mathematics》 2020年第12期1275-1291,共17页
Credit card fraudulent data is highly imbalanced, and it has presented an overwhelmingly large portion of nonfraudulent transactions and a small portion of fraudulent transactions. The measures used to judge the verac... Credit card fraudulent data is highly imbalanced, and it has presented an overwhelmingly large portion of nonfraudulent transactions and a small portion of fraudulent transactions. The measures used to judge the veracity of the detection algorithms become critical to the deployment of a model that accurately scores fraudulent transactions taking into account case imbalance, and the cost of identifying a case as genuine when, in fact, the case is a fraudulent transaction. In this paper, a new criterion to judge classification algorithms, which considers the cost of misclassification, is proposed, and several undersampling techniques are compared by this new criterion. At the same time, a weighted support vector machine (SVM) algorithm considering the financial cost of misclassification is introduced, proving to be more practical for credit card fraud detection than traditional methodologies. This weighted SVM uses transaction balances as weights for fraudulent transactions, and a uniformed weight for nonfraudulent transactions. The results show this strategy greatly improve performance of credit card fraud detection. 展开更多
关键词 support vector machine binary Classification Imbalanced Data UNDERSAMPLING Credit Card Fraud
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Evaluations of Machine Learning Algorithms Using Simulation Study
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作者 Nasrin Khatun 《Open Journal of Statistics》 2025年第1期41-52,共12页
1st cases of COVID-19 were reported in March 2020 in Bangladesh and rapidly increased daily. So many steps were taken by the Bangladesh government to reduce the outbreak of COVID-19, such as masks, gatherings, local m... 1st cases of COVID-19 were reported in March 2020 in Bangladesh and rapidly increased daily. So many steps were taken by the Bangladesh government to reduce the outbreak of COVID-19, such as masks, gatherings, local movements, international movements, etc. The data was collected from the World Health Organization. In this research, different variables have been used for analysis, for instance, new cases, new deaths, masks, schools, business, gatherings, domestic movement, international travel, new test, positive rate, test per case, new vaccination smoothed, new vaccine, total vaccination, and stringency index. Machine learning algorithms were used to predict and build the model, such as linear regression, K-nearest neighbours, decision trees, random forests, and support vector machines. Accuracy and Mean Square error (MSE) were used to test the model. A hyperparameter was also applied to find the optimum values of parameters. After computing the analysis, the result showed that the linear regression algorithm performs the best overall among the algorithms listed, with the highest testing accuracy and the lowest RMSE before and after hyper-tuning. The highest accuracy and lowest MSE were used for the best model, and for this data set, Linear regression got the highest accuracy, 0.98 and 0.97 and the lowest MSE, 4.79 and 4.04, respectively. 展开更多
关键词 Linear Regression K-Nearest Neighbours Decision tree Random Forest support vector machine Hyper-Tuning
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Analysing Effectiveness of Sentiments in Social Media Data Using Machine Learning Techniques
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作者 Thambusamy Velmurugan Mohandas Archana Ajith Singh Nongmaithem 《Journal of Computer and Communications》 2025年第1期136-151,共16页
Every second, a large volume of useful data is created in social media about the various kind of online purchases and in another forms of reviews. Particularly, purchased products review data is enormously growing in ... Every second, a large volume of useful data is created in social media about the various kind of online purchases and in another forms of reviews. Particularly, purchased products review data is enormously growing in different database repositories every day. Most of the review data are useful to new customers for theier further purchases as well as existing companies to view customers feedback about various products. Data Mining and Machine Leaning techniques are familiar to analyse such kind of data to visualise and know the potential use of the purchased items through online. The customers are making quality of products through their sentiments about the purchased items from different online companies. In this research work, it is analysed sentiments of Headphone review data, which is collected from online repositories. For the analysis of Headphone review data, some of the Machine Learning techniques like Support Vector Machines, Naive Bayes, Decision Trees and Random Forest Algorithms and a Hybrid method are applied to find the quality via the customers’ sentiments. The accuracy and performance of the taken algorithms are also analysed based on the three types of sentiments such as positive, negative and neutral. 展开更多
关键词 support vector machine Random Forest Algorithm Naive Bayes Algorithm machine Learning Techniques Decision tree Algorithm
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Utilizing Machine Learning and SHAP Values for Improved and Transparent Energy Usage Predictions
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作者 Faisal Ghazi Beshaw Thamir Hassan Atyia +2 位作者 Mohd Fadzli Mohd Salleh Mohamad Khairi Ishak Abdul Sattar Din 《Computers, Materials & Continua》 2025年第5期3553-3583,共31页
The significance of precise energy usage forecasts has been highlighted by the increasing need for sustainability and energy efficiency across a range of industries.In order to improve the precision and openness of en... The significance of precise energy usage forecasts has been highlighted by the increasing need for sustainability and energy efficiency across a range of industries.In order to improve the precision and openness of energy consumption projections,this study investigates the combination of machine learning(ML)methods with Shapley additive explanations(SHAP)values.The study evaluates three distinct models:the first is a Linear Regressor,the second is a Support Vector Regressor,and the third is a Decision Tree Regressor,which was scaled up to a Random Forest Regressor/Additions made were the third one which was Regressor which was extended to a Random Forest Regressor.These models were deployed with the use of Shareable,Plot-interpretable Explainable Artificial Intelligence techniques,to improve trust in the AI.The findings suggest that our developedmodels are superior to the conventional models discussed in prior studies;with high Mean Absolute Error(MAE)and Root Mean Squared Error(RMSE)values being close to perfection.In detail,the Random Forest Regressor shows the MAE of 0.001 for predicting the house prices whereas the SVR gives 0.21 of MAE and 0.24 RMSE.Such outcomes reflect the possibility of optimizing the use of the promoted advanced AI models with the use of Explainable AI for more accurate prediction of energy consumption and at the same time for the models’decision-making procedures’explanation.In addition to increasing prediction accuracy,this strategy gives stakeholders comprehensible insights,which facilitates improved decision-making and fosters confidence in AI-powered energy solutions.The outcomes show how well ML and SHAP work together to enhance prediction performance and guarantee transparency in energy usage projections. 展开更多
关键词 Renewable energy consumption machine learning explainable AI random forest support vector machine decision trees forecasting energy modeling
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Evaluating machine learning methods for predicting groundwater fluctuations using GRACE satellite in arid and semi-arid regions
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作者 Mobin Eftekhari Abbas Khashei-Siuki 《Journal of Groundwater Science and Engineering》 2025年第1期5-21,共17页
This study aims to evaluate the effectiveness of machine learning techniques for predicting groundwater fluctuations in arid and semi-arid regions using data from the Gravity Recovery and Climate Experiment satellite ... This study aims to evaluate the effectiveness of machine learning techniques for predicting groundwater fluctuations in arid and semi-arid regions using data from the Gravity Recovery and Climate Experiment satellite mission.The primary objective is to develop accurate predictive models for groundwa-ter level changes by leveraging the unique capabilities of GRACE satellite data in conjunction with advanced machine learning algorithms.Three widely-used machine learning models,namely DT,SVM and RF,were employed to analyze and model the relationship between GRACE satellite data and groundwater fluctuations in South Khorasan Province,Iran.The study utilized 151 months of GRACE data spanning from 2002 to 2017,which were correlated with piezometer well data available in the study area.The JPL 2 model was selected based on its strong correlation(R=0.9368)with the observed data.The machine learn-ing models were trained and validated using a 70/30 split of the data,and their performance was evaluated 2 using various statistical metrics,including RMSE,R and NSE.The results demonstrated the suitability of machine learning approaches for modeling groundwater fluctuations using GRACE satellite data.The DT 2 model exhibited the best performance during the calibration stage,with an R value of 0.95,RMSE of 20.655,and NSE of 0.96.The SVM and RF models achieved R values of 0.79 and 0.65,and NSE values of 0.86 and 0.71,respectively.For the prediction stage,the DT model maintained its high efficiency,with an 2 RMSE of 1.48,R of 0.87,and NSE of 0.90,indicating its robustness in predicting future groundwater fluc-tuations using GRACE data.The study highlights the potential of machine learning techniques,particularly Decision Trees,in conjunction with GRACE satellite data,for accurate prediction and monitoring of groundwater fluctuations in arid and semi-arid regions.The findings demonstrate the effectiveness of the DT model in capturing the complex relationships between GRACE data and groundwater dynamics,provid-ing reliable predictions and insights for sustainable groundwater management strategies. 展开更多
关键词 Decision trees support vector machines Random Forests GRACE Satellite Groundwater level
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Distance Estimation and Material Classification of a Compliant Tactile Sensor Using Vibration Modes and Support Vector Machine
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作者 S.R.GUNASEKARA H.N.T.K.KALDERA +1 位作者 N.HARISCHANDRA L.SAMARANAYAKE 《Instrumentation》 2019年第1期34-47,共14页
Many animals possess actively movable tactile sensors in their heads,to explore the near-range space.During locomotion,an antenna is used in near range orientation,for example,in detecting,localizing,probing,and negot... Many animals possess actively movable tactile sensors in their heads,to explore the near-range space.During locomotion,an antenna is used in near range orientation,for example,in detecting,localizing,probing,and negotiating obstacles.A bionic tactile sensor used in the present work was inspired by the antenna of the stick insects.The sensor is able to detect an obstacle and its location in 3 D(Three dimensional) space.The vibration signals are analyzed in the frequency domain using Fast Fourier Transform(FFT) to estimate the distances.Signal processing algorithms,Artificial Neural Network(ANN) and Support Vector Machine(SVM) are used for the analysis and prediction processes.These three prediction techniques are compared for both distance estimation and material classification processes.When estimating the distances,the accuracy of estimation is deteriorated towards the tip of the probe due to the change in the vibration modes.Since the vibration data within that region have high a variance,the accuracy in distance estimation and material classification are lower towards the tip.The change in vibration mode is mathematically analyzed and a solution is proposed to estimate the distance along the full range of the probe. 展开更多
关键词 VIBRATION based active TACTILE sensor Artificial Neural Network support vector machines DISTANCE estimation VIBRATION MODES Euler-Bernoulli beam element
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Binary Image Steganalysis Based on Distortion Level Co-Occurrence Matrix 被引量:2
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作者 Junjia Chen Wei Lu +4 位作者 Yuileong Yeung Yingjie Xue Xianjin Liu Cong Lin Yue Zhang 《Computers, Materials & Continua》 SCIE EI 2018年第5期201-211,共11页
In recent years,binary image steganography has developed so rapidly that the research of binary image steganalysis becomes more important for information security.In most state-of-the-art binary image steganographic s... In recent years,binary image steganography has developed so rapidly that the research of binary image steganalysis becomes more important for information security.In most state-of-the-art binary image steganographic schemes,they always find out the flippable pixels to minimize the embedding distortions.For this reason,the stego images generated by the previous schemes maintain visual quality and it is hard for steganalyzer to capture the embedding trace in spacial domain.However,the distortion maps can be calculated for cover and stego images and the difference between them is significant.In this paper,a novel binary image steganalytic scheme is proposed,which is based on distortion level co-occurrence matrix.The proposed scheme first generates the corresponding distortion maps for cover and stego images.Then the co-occurrence matrix is constructed on the distortion level maps to represent the features of cover and stego images.Finally,support vector machine,based on the gaussian kernel,is used to classify the features.Compared with the prior steganalytic methods,experimental results demonstrate that the proposed scheme can effectively detect stego images. 展开更多
关键词 binary image steganalysis informational security embedding distortion distortion level map co-occurrence matrix support vector machine.
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A Fast Algorithm for Support Vector Clustering
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作者 吕常魁 姜澄宇 王宁生 《Journal of Southwest Jiaotong University(English Edition)》 2004年第2期136-140,共5页
Support Vector Clustering (SVC) is a kernel-based unsupervised learning clustering method. The main drawback of SVC is its high computational complexity in getting the adjacency matrix describing the connectivity for ... Support Vector Clustering (SVC) is a kernel-based unsupervised learning clustering method. The main drawback of SVC is its high computational complexity in getting the adjacency matrix describing the connectivity for each pairs of points. Based on the proximity graph model [3], the Euclidean distance in Hilbert space is calculated using a Gaussian kernel, which is the right criterion to generate a minimum spanning tree using Kruskal's algorithm. Then the connectivity estimation is lowered by only checking the linkages between the edges that construct the main stem of the MST (Minimum Spanning Tree), in which the non-compatibility degree is originally defined to support the edge selection during linkage estimations. This new approach is experimentally analyzed. The results show that the revised algorithm has a better performance than the proximity graph model with faster speed, optimized clustering quality and strong ability to noise suppression, which makes SVC scalable to large data sets. 展开更多
关键词 support vector machines support vector clustering Proximity graph Minimum spanning tree
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The Design of Predictive Model for the Academic Performance of Students at University Based on Machine Learning
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作者 Barnabas Ndlovu Gatsheni Olga Ngala Katambwa 《Journal of Electrical Engineering》 2018年第4期229-237,共9页
Students in South African Universities come from different socio-cultural backgrounds, countries and high schools. This suggests that these students have different experiences which impact on their levels of grasping ... Students in South African Universities come from different socio-cultural backgrounds, countries and high schools. This suggests that these students have different experiences which impact on their levels of grasping information in class as they potentially use different lenses on tuition. The current practice in Universities in contributing to the academic performance of students includes the use of tutors, the use of mobile devices for first year students, use of student assistants and the use of different feedback measures. What is problematic about the current practice is that students are quitting university in high numbers. In this study, knowledge has been drawn from data through the use of machine learning algorithms. Bayesian networks, support vector machines (SVMs) and decision trees algorithms were used individually in this work to construct predictive models for the academic performance of students. The best model was constructed using SVM and it gave a prediction of 72.87% and a prediction cost of 139. The model does predict the performance of students in advance of the year-end examinations outcome. The results suggest that South African Universities must recognize the diversity in student population and thus provide students with better support and equip them with the necessary knowledge that will enable them to tap into their full potential and thus enhance their skills. 展开更多
关键词 machine learning Bayesian networks support vector machines decision trees and predictive model.
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Credit Card Fraud Detection Using Machine Learning Techniques
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作者 Ananya Sarker Must. Asma Yasmin +2 位作者 Md. Atikur Rahman Md. Harun Or Rashid Bristi Rani Roy 《Journal of Computer and Communications》 2024年第6期1-11,共11页
Credit card companies must be able to identify fraudulent credit card transactions so that clients are not charged for items they did not purchase. Previously, many machine learning approaches and classifiers were use... Credit card companies must be able to identify fraudulent credit card transactions so that clients are not charged for items they did not purchase. Previously, many machine learning approaches and classifiers were used to detect fraudulent transactions. However, because fraud patterns are always changing, it is becoming increasingly vital to investigate new frauds and develop the model based on the new patterns. The purpose of this research is to create a machine learning classifier that not only detects fraud but also detects legitimate transactions. As a result, the model should have excellent accuracy, precision, recall, and f1-score. As a result, we began with a large dataset in this study and used four machine learning classifiers: Support Vector Machine (SVM), Decision Tree, Naïve Bayes, and Random Forest. The random forest classifier scored 99.96% overall accuracy with the best precision, recall, f1-score, and Matthews correlation coefficient in the experiments. 展开更多
关键词 support vector machine Decision tree Nave Bayes Random Forest Matthews Correlation
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Research on Vehicle Tracking Method Based on YOLOv8 and Adaptive Kalman Filtering: Integrating SVM Dynamic Selection and Error Feedback Mechanism
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作者 Liping Zheng Hao Gou +1 位作者 Kaiwen Xiao Moran Qiu 《Open Journal of Applied Sciences》 2024年第12期3569-3588,共20页
Vehicle tracking plays a crucial role in intelligent transportation, autonomous driving, and video surveillance. However, challenges such as occlusion, multi-target interference, and nonlinear motion in dynamic scenar... Vehicle tracking plays a crucial role in intelligent transportation, autonomous driving, and video surveillance. However, challenges such as occlusion, multi-target interference, and nonlinear motion in dynamic scenarios make tracking accuracy and stability a focus of ongoing research. This paper proposes an integrated method combining YOLOv8 object detection with adaptive Kalman filtering. The approach employs a support vector machine (SVM) to dynamically select the optimal filter (including standard Kalman filter, extended Kalman filter, and unscented Kalman filter), enhancing the system’s adaptability to different motion patterns. Additionally, an error feedback mechanism is incorporated to dynamically adjust filter parameters, further improving responsiveness to sudden events. Experimental results on the KITTI and UA-DETRAC datasets demonstrate that the proposed method significantly improves detection accuracy (mAP@0.5 increased by approximately 3%), tracking accuracy (MOTA improved by 5%), and system robustness, providing an efficient solution for vehicle tracking in complex environments. 展开更多
关键词 Multi-Target Tracking YOLOv8-based Detection Adaptive Filtering support vector machine Error Feedback Mechanism
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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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Finger vein recognition using weighted local binary pattern code based on a support vector machine 被引量:15
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作者 Hyeon Chang LEE Byung Jun KANG +1 位作者 Eui Chul LEE Kang Ryoung PARK 《Journal of Zhejiang University-Science C(Computers and Electronics)》 SCIE EI 2010年第7期514-524,共11页
Finger vein recognition is a biometric technique which identifies individuals using their unique finger vein patterns. It is reported to have a high accuracy and rapid processing speed. In addition, it is impossible t... Finger vein recognition is a biometric technique which identifies individuals using their unique finger vein patterns. It is reported to have a high accuracy and rapid processing speed. In addition, it is impossible to steal a vein pattern located inside the finger. We propose a new identification method of finger vascular patterns using a weighted local binary pattern (LBP) and support vector machine (SVM). This research is novel in the following three ways. First, holistic codes are extracted through the LBP method without using a vein detection procedure. This reduces the processing time and the complexities in detecting finger vein patterns. Second, we classify the local areas from which the LBP codes are extracted into three categories based on the SVM classifier: local areas that include a large amount (LA), a medium amount (MA), and a small amount (SA) of vein patterns. Third, different weights are assigned to the extracted LBP code according to the local area type (LA, MA, and SA) from which the LBP codes were extracted. The optimal weights are determined empirically in terms of the accuracy of the finger vein recognition. Experimental results show that our equal error rate (EER) is significantly lower compared to that without the proposed method or using a conventional method. 展开更多
关键词 Finger vein recognition support vector machine (SVM) WEIGHT Local binary pattern (LBP)
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Science Letters:Binary tree of posterior probability support vector machines 被引量:2
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作者 Dong-li WANG Jian-guo ZHENG Yan ZHOU 《Journal of Zhejiang University-Science C(Computers and Electronics)》 SCIE EI 2011年第2期83-87,共5页
Posterior probability support vector machines (PPSVMs) prove robust against noises and outliers and need fewer storage support vectors (SVs). Gonen et al. (2008) extended PPSVMs to a multiclass case by both single-mac... Posterior probability support vector machines (PPSVMs) prove robust against noises and outliers and need fewer storage support vectors (SVs). Gonen et al. (2008) extended PPSVMs to a multiclass case by both single-machine and multimachine approaches. However, these extensions suffer from low classification efficiency, high computational burden, and more importantly, unclassifiable regions. To achieve higher classification efficiency and accuracy with fewer SVs, a binary tree of PPSVMs for the multiclass classification problem is proposed in this letter. Moreover, a Fisher ratio separability measure is adopted to determine the tree structure. Several experiments on handwritten recognition datasets are included to illustrate the proposed approach. Specifically, the Fisher ratio separability accelerated binary tree of PPSVMs obtains overall test accuracy, if not higher than, at least comparable to those of other multiclass algorithms, while using significantly fewer SVs and much less test time. 展开更多
关键词 binary tree support vector machine Handwritten recognition Classification
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压力容器气体泄漏的GSABO-VMD与CNN-SVM分类方法研究
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作者 张涛 张诗云 +1 位作者 孙君峰 朱菊香 《自动化与仪表》 2025年第2期93-98,共6页
以压力容器气体泄漏展开研究,提出了一种融合黄金正弦的减法平均优化器(subtraction-average-based optimizer with golden sine,GSABO)、优化变分模态分解(variational mode decomposition,VMD)和卷积神经网络(convolutional neural ne... 以压力容器气体泄漏展开研究,提出了一种融合黄金正弦的减法平均优化器(subtraction-average-based optimizer with golden sine,GSABO)、优化变分模态分解(variational mode decomposition,VMD)和卷积神经网络(convolutional neural network,CNN)与支持向量机(support vector machine,SVM)联合分类检测的方法。首先,引入了融合黄金正弦的减法平均优化器对变分模态分解的参数模态个数K和惩罚参数α进行寻优,将最小包络熵为适应度函数得到最佳的K和惩罚参数α,计算最佳IMF分量的9种时域指标构建特征向量,输入CNN-SVM联合的分类方法进行特征提取并对气体泄漏情况进行识别。经实验分析,提出的引入融合黄金正弦的减法平均优化器优化后的VMD方法能够有效地自适应获取最优参数组,然后对压力容器气体泄漏声波信号进行特征提取,选取最优的特征组合输入CNNSVM联合分类检测,得到泄漏与否判别准确率高达99.16%,有助于对后续研究进一步开展。 展开更多
关键词 压力容器泄漏 气体泄漏检测 变分模态分解 减法平均优化器 黄金正弦 气体泄漏识别 卷积神经网络 支持向量机
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基于机器学习的冠心病风险预测模型构建与比较 被引量:1
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作者 岳海涛 何婵婵 +3 位作者 成羽攸 张森诚 吴悠 马晶 《中国全科医学》 CAS 北大核心 2025年第4期499-509,共11页
背景冠状动脉粥样硬化性心脏病(以下简称冠心病)是全球重要的死亡原因之一。目前关于冠心病风险评估的研究在逐年增长。然而,在这些研究中常忽略了数据不平衡的问题,而解决该问题对于提高分类算法中识别冠心病风险的准确性至关重要。目... 背景冠状动脉粥样硬化性心脏病(以下简称冠心病)是全球重要的死亡原因之一。目前关于冠心病风险评估的研究在逐年增长。然而,在这些研究中常忽略了数据不平衡的问题,而解决该问题对于提高分类算法中识别冠心病风险的准确性至关重要。目的探索冠心病的影响因素,通过使用2种平衡数据的方法,基于5种算法建立冠心病风险相关的预测模型,比较这5种模型对冠心病风险的预测价值。方法基于2021年美国国家行为风险因素监测系统(BRFSS)横断面调查数据筛选出112606名研究对象的健康相关风险行为、慢性健康状况等24个变量信息,结局指标为自我报告是否患有冠心病并据此分为冠心病组和非冠心病组。通过进行单因素分析和逐步Logistic回归分析探索冠心病发生的影响因素并筛选出纳入预测模型的变量。随机抽取112606名受访者的10%(共计11261名),以8∶2的比例随机划分为训练与测试的数据集,采用随机过采样和合成少数过采样技术(SMOTE)两种过采样的方法处理不平衡数据,基于k最邻近算法(KNN)、Logistic回归、支持向量机(SVM)、决策树和XGBoost算法分别建立冠心病预测模型。结果两组年龄、性别、BMI、种族、婚姻状态、教育水平、收入水平、家里有几个孩子、是否被告知患高血压、是否被告知处于高血压前期、是否被告知患妊娠高血压、现在是否在服用高血压药物、是否被告知患有高脂血症、是否被告知患有糖尿病、吸烟情况、过去30 d内是否至少喝过1次酒、是否为重度饮酒者、是否为酗酒者、过去30 d内是否有体育锻炼、心理健康状况以及自我健康评价比较,差异有统计学意义(P<0.05)。逐步Logistic回归分析结果显示:年龄、性别、BMI、种族、教育水平、收入水平、是否被告知患高血压、是否被告知处于高血压前期、是否被告知患妊娠高血压、现在是否在服用高血压药物、是否被告知患有高脂血症、是否被告知患有糖尿病、吸烟情况、过去30 d内是否至少喝过1次酒、是否为重度饮酒者、是否为酗酒者以及自我健康评价为冠心病的影响因素(P<0.05)。风险模型构建的分析结果显示:k最邻近算法、Logistic回归、支持向量机、决策树和XGBoost采用SMOTE处理不平衡数据的总体分类精度分别为59.2%、67.4%、66.2%、69.2%和85.9%,召回率分别为75.2%、71.4%、70.5%、62.9%和34.8%,精确度分别为15.4%、18.2%、17.5%、17.6%和28.7%,F值分别为0.256、0.290、0.280、0.275和0.315,受试者工作特征曲线下面积分别为0.80、0.78、0.72、0.72和0.82;采用随机过采样处理不平衡数据的总体分类精度分别为62.5%、68.5%、69.0%、60.2%和70.1%,召回率分别为70.0%、69.5%、71.9%、69.0%和67.6%;精确度分别为15.8%、18.4%、19.1%、14.8%和19.0%,F值分别为0.258、0.291、0.302、0.244和0.297,受试者工作特征曲线下面积分别为0.80、0.77、0.72、0.72和0.83。结论本研究不仅确认了已知冠心病的影响因素,还发现了自我健康评价水平、收入水平和教育水平对冠心病具有潜在影响。在使用2种数据平衡方法后,5种算法的性能显著提高。其中XGBoost模型表现最佳,可作为未来优化冠心病预测模型的参考。此外,鉴于XGBoost模型的优异性能以及逐步Logistic回归的操作便捷和可解释性,推荐在冠心病风险预测模型中结合使用数据平衡后的XGBoost和逐步Logistic回归分析。 展开更多
关键词 冠心病 机器学习 风险预测模型 LOGISTIC回归 k最邻近算法 支持向量机 决策树 XGBoost
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基于改进的LBP和Gabor滤波器的纹理特征提取方法
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作者 陈佳明 陈旭 +1 位作者 任硕 邸宏伟 《南京信息工程大学学报》 北大核心 2025年第2期227-234,共8页
纹理提取是计算机视觉领域的一项重要任务,纹理提取的质量对纹理分类的准确性具有关键影响.传统单一的纹理提取方法难以准确描述各类纹理的特征.本文提出一种基于改进的位置局部二值模式(IPLBP)和Gabor滤波器的纹理提取算法,其中,改进... 纹理提取是计算机视觉领域的一项重要任务,纹理提取的质量对纹理分类的准确性具有关键影响.传统单一的纹理提取方法难以准确描述各类纹理的特征.本文提出一种基于改进的位置局部二值模式(IPLBP)和Gabor滤波器的纹理提取算法,其中,改进算法在局部二值模式(LBP)的基础上通过提取纹理位置信息来提高纹理描述能力.利用改进后的LBP算法提取局部纹理信息,Gabor滤波器提取全局纹理信息,将两种特征信息进行融合后使用支持向量机(SVM)进行分类.实验结果表明,所提出的算法在纹理材质分类任务上展现出了良好的性能.相比传统的LBP算法,该算法能够更准确地捕捉不同纹理特征之间的差异. 展开更多
关键词 纹理提取 局部二值模式 GABOR滤波器 支持向量机
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基于改进深度学习框架的教师贡献自动评价系统
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作者 叶颖 陈伟 《广西科技大学学报》 2025年第1期72-79,共8页
学生反馈对于评估教学质量和教师绩效至关重要,但将文本形式的大量教学反馈自动量化为教师贡献评价指标是一个难题。为此,提出了基于BERT (bidirectional encoder representation from transformers)和句法依存树的方面级文本情感分析模... 学生反馈对于评估教学质量和教师绩效至关重要,但将文本形式的大量教学反馈自动量化为教师贡献评价指标是一个难题。为此,提出了基于BERT (bidirectional encoder representation from transformers)和句法依存树的方面级文本情感分析模型,利用教学反馈文本评估与教学质量相关的不同方面,包括师德、教学内容、教学态度、教师能力和学习环境。对于反馈文本采用基于句法依存树的句子嵌入学习,并结合关联词表嵌入,以及基于BERT的上下文嵌入,经过多头注意力机制执行特征融合后,提取高质量隐藏特征。其后,使用基于不同机器学习算法的分类器确定情感极性,得到学生对特定教学方面的满意度,从而实现对教师贡献的量化评价。实验结果表明,自由文本形式的学生反馈能够比量表打分更好地衡量不同方面的教学质量。此外,所提框架能够准确提取出反馈文本中不同的教学方面,准确度和F1值分别为89.72%和88.91%,性能优于其他方面级情感分析方法。 展开更多
关键词 深度学习 情感分析 教学质量评价 句法依存树 BERT 支持向量机
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