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Improved Twin Support Vector Machine Algorithm and Applications in Classification Problems
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作者 Sun Yi Wang Zhouyang 《China Communications》 SCIE CSCD 2024年第5期261-279,共19页
The distribution of data has a significant impact on the results of classification.When the distribution of one class is insignificant compared to the distribution of another class,data imbalance occurs.This will resu... The distribution of data has a significant impact on the results of classification.When the distribution of one class is insignificant compared to the distribution of another class,data imbalance occurs.This will result in rising outlier values and noise.Therefore,the speed and performance of classification could be greatly affected.Given the above problems,this paper starts with the motivation and mathematical representing of classification,puts forward a new classification method based on the relationship between different classification formulations.Combined with the vector characteristics of the actual problem and the choice of matrix characteristics,we firstly analyze the orderly regression to introduce slack variables to solve the constraint problem of the lone point.Then we introduce the fuzzy factors to solve the problem of the gap between the isolated points on the basis of the support vector machine.We introduce the cost control to solve the problem of sample skew.Finally,based on the bi-boundary support vector machine,a twostep weight setting twin classifier is constructed.This can help to identify multitasks with feature-selected patterns without the need for additional optimizers,which solves the problem of large-scale classification that can’t deal effectively with the very low category distribution gap. 展开更多
关键词 FUZZY ordered regression(OR) relaxing variables twin support vector machine
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Combination Computing of Support Vector Machine, Support Vector Regression and Molecular Docking for Potential Cytochrome P450 1A2 Inhibitors 被引量:1
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作者 陈茜 乔连生 +2 位作者 蔡漪涟 张燕玲 李贡宇 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2016年第5期629-634,I0002,共7页
The computational approaches of support vector machine (SVM), support vector regression (SVR) and molecular docking were widely utilized for the computation of active compounds. In this work, to improve the accura... The computational approaches of support vector machine (SVM), support vector regression (SVR) and molecular docking were widely utilized for the computation of active compounds. In this work, to improve the accuracy and reliability of prediction, the strategy of combining the above three computational approaches was applied to predict potential cytochrome P450 1A2 (CYP1A2) inhibitors. The accuracy of the optimal SVM qualitative model was 99.432%, 97.727%, and 91.667% for training set, internal test set and external test set, respectively, showing this model had high discrimination ability. The R2 and mean square error for the optimal SVR quantitative model were 0.763, 0.013 for training set, and 0.753, 0.056 for test set respectively, indicating that this SVR model has high predictive ability for the biolog-ical activities of compounds. According to the results of the SVM and SVR models, some types of descriptors were identi ed to be essential to bioactivity prediction of compounds, including the connectivity indices, constitutional descriptors and functional group counts. Moreover, molecular docking studies were used to reveal the binding poses and binding a n-ity of potential inhibitors interacting with CYP1A2. Wherein, the amino acids of THR124 and ASP320 could form key hydrogen bond interactions with active compounds. And the amino acids of ALA317 and GLY316 could form strong hydrophobic bond interactions with active compounds. The models obtained above were applied to discover potential CYP1A2 inhibitors from natural products, which could predict the CYPs-mediated drug-drug inter-actions and provide useful guidance and reference for rational drug combination therapy. A set of 20 potential CYP1A2 inhibitors were obtained. Part of the results was consistent with references, which further indicates the accuracy of these models and the reliability of this combinatorial computation strategy. 展开更多
关键词 support vector machine support vector regression Molecular docking CYPIA2 inhibitor
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POSITIVE DEFINITE KERNEL IN SUPPORT VECTOR MACHINE(SVM) 被引量:3
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作者 谢志鹏 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2009年第2期114-121,共8页
The relationship among Mercer kernel, reproducing kernel and positive definite kernel in support vector machine (SVM) is proved and their roles in SVM are discussed. The quadratic form of the kernel matrix is used t... The relationship among Mercer kernel, reproducing kernel and positive definite kernel in support vector machine (SVM) is proved and their roles in SVM are discussed. The quadratic form of the kernel matrix is used to confirm the positive definiteness and their construction. Based on the Bochner theorem, some translation invariant kernels are checked in their Fourier domain. Some rotation invariant radial kernels are inspected according to the Schoenberg theorem. Finally, the construction of discrete scaling and wavelet kernels, the kernel selection and the kernel parameter learning are discussed. 展开更多
关键词 support vector machines(svms) mercer kernel reproducing kernel positive definite kernel scaling and wavelet kernel
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Machine learning model based on non-convex penalized huberized-SVM
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作者 Peng Wang Ji Guo Lin-Feng Li 《Journal of Electronic Science and Technology》 EI CAS CSCD 2024年第1期81-94,共14页
The support vector machine(SVM)is a classical machine learning method.Both the hinge loss and least absolute shrinkage and selection operator(LASSO)penalty are usually used in traditional SVMs.However,the hinge loss i... The support vector machine(SVM)is a classical machine learning method.Both the hinge loss and least absolute shrinkage and selection operator(LASSO)penalty are usually used in traditional SVMs.However,the hinge loss is not differentiable,and the LASSO penalty does not have the Oracle property.In this paper,the huberized loss is combined with non-convex penalties to obtain a model that has the advantages of both the computational simplicity and the Oracle property,contributing to higher accuracy than traditional SVMs.It is experimentally demonstrated that the two non-convex huberized-SVM methods,smoothly clipped absolute deviation huberized-SVM(SCAD-HSVM)and minimax concave penalty huberized-SVM(MCP-HSVM),outperform the traditional SVM method in terms of the prediction accuracy and classifier performance.They are also superior in terms of variable selection,especially when there is a high linear correlation between the variables.When they are applied to the prediction of listed companies,the variables that can affect and predict financial distress are accurately filtered out.Among all the indicators,the indicators per share have the greatest influence while those of solvency have the weakest influence.Listed companies can assess the financial situation with the indicators screened by our algorithm and make an early warning of their possible financial distress in advance with higher precision. 展开更多
关键词 Huberized loss machine learning Non-convex penalties support vector machine(svm)
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Facial Expression Recognition Model Depending on Optimized Support Vector Machine 被引量:1
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作者 Amel Ali Alhussan Fatma M.Talaat +4 位作者 El-Sayed M.El-kenawy Abdelaziz A.Abdelhamid Abdelhameed Ibrahim Doaa Sami Khafaga Mona Alnaggar 《Computers, Materials & Continua》 SCIE EI 2023年第7期499-515,共17页
In computer vision,emotion recognition using facial expression images is considered an important research issue.Deep learning advances in recent years have aided in attaining improved results in this issue.According t... In computer vision,emotion recognition using facial expression images is considered an important research issue.Deep learning advances in recent years have aided in attaining improved results in this issue.According to recent studies,multiple facial expressions may be included in facial photographs representing a particular type of emotion.It is feasible and useful to convert face photos into collections of visual words and carry out global expression recognition.The main contribution of this paper is to propose a facial expression recognitionmodel(FERM)depending on an optimized Support Vector Machine(SVM).To test the performance of the proposed model(FERM),AffectNet is used.AffectNet uses 1250 emotion-related keywords in six different languages to search three major search engines and get over 1,000,000 facial photos online.The FERM is composed of three main phases:(i)the Data preparation phase,(ii)Applying grid search for optimization,and(iii)the categorization phase.Linear discriminant analysis(LDA)is used to categorize the data into eight labels(neutral,happy,sad,surprised,fear,disgust,angry,and contempt).Due to using LDA,the performance of categorization via SVM has been obviously enhanced.Grid search is used to find the optimal values for hyperparameters of SVM(C and gamma).The proposed optimized SVM algorithm has achieved an accuracy of 99%and a 98%F1 score. 展开更多
关键词 Facial expression recognition machine learning linear dis-criminant analysis(LDA) support vector machine(svm) grid search
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Small-time scale network traffic prediction based on a local support vector machine regression model 被引量:10
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作者 孟庆芳 陈月辉 彭玉华 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第6期2194-2199,共6页
In this paper we apply the nonlinear time series analysis method to small-time scale traffic measurement data. The prediction-based method is used to determine the embedding dimension of the traffic data. Based on the... In this paper we apply the nonlinear time series analysis method to small-time scale traffic measurement data. The prediction-based method is used to determine the embedding dimension of the traffic data. Based on the reconstructed phase space, the local support vector machine prediction method is used to predict the traffic measurement data, and the BIC-based neighbouring point selection method is used to choose the number of the nearest neighbouring points for the local support vector machine regression model. The experimental results show that the local support vector machine prediction method whose neighbouring points are optimized can effectively predict the small-time scale traffic measurement data and can reproduce the statistical features of real traffic measurements. 展开更多
关键词 network traffic small-time scale nonlinear time series analysis support vector machine regression model
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Support Vector Machines for Regression: A Succinct Review of Large-Scale and Linear Programming Formulations 被引量:3
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作者 Pablo Rivas-Perea Juan Cota-Ruiz +3 位作者 David Garcia Chaparro Jorge Arturo Perez Venzor Abel Quezada Carreón Jose Gerardo Rosiles 《International Journal of Intelligence Science》 2013年第1期5-14,共10页
Support Vector-based learning methods are an important part of Computational Intelligence techniques. Recent efforts have been dealing with the problem of learning from very large datasets. This paper reviews the most... Support Vector-based learning methods are an important part of Computational Intelligence techniques. Recent efforts have been dealing with the problem of learning from very large datasets. This paper reviews the most commonly used formulations of support vector machines for regression (SVRs) aiming to emphasize its usability on large-scale applications. We review the general concept of support vector machines (SVMs), address the state-of-the-art on training methods SVMs, and explain the fundamental principle of SVRs. The most common learning methods for SVRs are introduced and linear programming-based SVR formulations are explained emphasizing its suitability for large-scale learning. Finally, this paper also discusses some open problems and current trends. 展开更多
关键词 support vector machineS support vector regression Linear PROGRAMMING support vector regression
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Prediction of protein binding sites using physical and chemical descriptors and the support vector machine regression method 被引量:1
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作者 孙重华 江凡 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第11期1-6,共6页
In this paper a new continuous variable called core-ratio is defined to describe the probability for a residue to be in a binding site, thereby replacing the previous binary description of the interface residue using ... In this paper a new continuous variable called core-ratio is defined to describe the probability for a residue to be in a binding site, thereby replacing the previous binary description of the interface residue using 0 and 1. So we can use the support vector machine regression method to fit the core-ratio value and predict the protein binding sites. We also design a new group of physical and chemical descriptors to characterize the binding sites. The new descriptors are more effective, with an averaging procedure used. Our test shows that much better prediction results can be obtained by the support vector regression (SVR) method than by the support vector classification method. 展开更多
关键词 protein binding site support vector machine regression cross-validation neighbour residue
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Comparison of School Building Construction Costs Estimation Methods Using Regression Analysis, Neural Network, and Support Vector Machine 被引量:2
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作者 Gwang-Hee Kim Jae-Min Shin +1 位作者 Sangyong Kim Yoonseok Shin 《Journal of Building Construction and Planning Research》 2013年第1期1-7,共7页
Accurate cost estimation at the early stage of a construction project is key factor in a project’s success. But it is difficult to quickly and accurately estimate construction costs at the planning stage, when drawin... Accurate cost estimation at the early stage of a construction project is key factor in a project’s success. But it is difficult to quickly and accurately estimate construction costs at the planning stage, when drawings, documentation and the like are still incomplete. As such, various techniques have been applied to accurately estimate construction costs at an early stage, when project information is limited. While the various techniques have their pros and cons, there has been little effort made to determine the best technique in terms of cost estimating performance. The objective of this research is to compare the accuracy of three estimating techniques (regression analysis (RA), neural network (NN), and support vector machine techniques (SVM)) by performing estimations of construction costs. By comparing the accuracy of these techniques using historical cost data, it was found that NN model showed more accurate estimation results than the RA and SVM models. Consequently, it is determined that NN model is most suitable for estimating the cost of school building projects. 展开更多
关键词 ESTIMATING Construction COSTS regression Analysis NEURAL Network support vector machine
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An Efficient and Robust Fall Detection System Using Wireless Gait Analysis Sensor with Artificial Neural Network (ANN) and Support Vector Machine (SVM) Algorithms 被引量:2
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作者 Bhargava Teja Nukala Naohiro Shibuya +5 位作者 Amanda Rodriguez Jerry Tsay Jerry Lopez Tam Nguyen Steven Zupancic Donald Yu-Chun Lie 《Open Journal of Applied Biosensor》 2014年第4期29-39,共11页
In this work, a total of 322 tests were taken on young volunteers by performing 10 different falls, 6 different Activities of Daily Living (ADL) and 7 Dynamic Gait Index (DGI) tests using a custom-designed Wireless Ga... In this work, a total of 322 tests were taken on young volunteers by performing 10 different falls, 6 different Activities of Daily Living (ADL) and 7 Dynamic Gait Index (DGI) tests using a custom-designed Wireless Gait Analysis Sensor (WGAS). In order to perform automatic fall detection, we used Back Propagation Artificial Neural Network (BP-ANN) and Support Vector Machine (SVM) based on the 6 features extracted from the raw data. The WGAS, which includes a tri-axial accelerometer, 2 gyroscopes, and a MSP430 microcontroller, is worn by the subjects at either T4 (at back) or as a belt-clip in front of the waist during the various tests. The raw data is wirelessly transmitted from the WGAS to a near-by PC for real-time fall classification. The BP ANN is optimized by varying the training, testing and validation data sets and training the network with different learning schemes. SVM is optimized by using three different kernels and selecting the kernel for best classification rate. The overall accuracy of BP ANN is obtained as 98.20% with LM and RPROP training from the T4 data, while from the data taken at the belt, we achieved 98.70% with LM and SCG learning. The overall accuracy using SVM was 98.80% and 98.71% with RBF kernel from the T4 and belt position data, respectively. 展开更多
关键词 Artificial Neural Network (ANN) Back Propagation FALL Detection FALL Prevention GAIT Analysis SENSOR support vector machine (svm) WIRELESS SENSOR
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Support Vector Machines(SVM)-Markov Chain Prediction Model of Mining Water Inflow 被引量:2
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作者 Kai HUANG 《Agricultural Science & Technology》 CAS 2017年第8期1551-1554,1558,共5页
This study was conducted to establish a Support Vector Machines(SVM)-Markov Chain prediction model for prediction of mining water inflow. According to the raw data sequence, the Support Vector Machines(SVM) model was ... This study was conducted to establish a Support Vector Machines(SVM)-Markov Chain prediction model for prediction of mining water inflow. According to the raw data sequence, the Support Vector Machines(SVM) model was built, and then revised by means of a Markov state change probability matrix. Through dividing the state and analyzing absolute errors and relative errors and other indexes of the measured value and the fitted value of SVM, the prediction results were improved. Finally,the model was used to calculate relative errors. Through predicting and analyzing mining water inflow, the prediction results of the model were satisfactory. The results of this study enlarge the application scope of the Support Vector Machines(SVM) prediction model and provide a new method for scientific forecasting water inflow in coal mining. 展开更多
关键词 Mining water inflow support vector machines svm Markov Chain
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Path Loss Modeling: A Machine Learning Based Approach Using Support Vector Regression and Radial Basis Function Models 被引量:3
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作者 Stephen Ojo Arif Sari Taiwo P. Ojo 《Open Journal of Applied Sciences》 2022年第6期990-1010,共21页
Path loss prediction models are vital for accurate signal propagation in wireless channels. Empirical and deterministic models used in path loss predictions have not produced optimal results. In this paper, we introdu... Path loss prediction models are vital for accurate signal propagation in wireless channels. Empirical and deterministic models used in path loss predictions have not produced optimal results. In this paper, we introduced machine learning algorithms to path loss predictions because it offers a flexible network architecture and extensive data can be used. We introduced support vector regression (SVR) and radial basis function (RBF) models to path loss predictions in the investigated environments. The SVR model was able to process several input parameters without introducing complexity to the network architecture. The RBF on its part provides a good function approximation. Hyperparameter tuning of the machine learning models was carried out in order to achieve optimal results. The performances of the SVR and RBF models were compared and result validated using the root-mean squared error (RMSE). The two machine learning algorithms were also compared with the Cost-231, SUI, Egli, Freespace, Cost-231 W-I models. The analytical models overpredicted path loss. Overall, the machine learning models predicted path loss with greater accuracy than the empirical models. The SVR model performed best across all the indices with RMSE values of 1.378 dB, 1.4523 dB, 2.1568 dB in rural, suburban and urban settings respectively and should therefore be adopted for signal propagation in the investigated environments and beyond. 展开更多
关键词 support vector regression Radial Basis Function machine Learning Path Loss Empirical DETERMINISTIC
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The seam offset identification based on support vector regression machines
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作者 曾松盛 石永华 +1 位作者 王国荣 黄国兴 《China Welding》 EI CAS 2009年第2期75-80,共6页
The principle of the support vector regression machine(SVR) is first analysed. Then the new data-dependent kernel function is constructed from information geometry perspective. The current waveforms change regularly... The principle of the support vector regression machine(SVR) is first analysed. Then the new data-dependent kernel function is constructed from information geometry perspective. The current waveforms change regularly in accordance with the different horizontal offset when the rotational frequency of the high speed rotational arc sensor is in the range from 15 Hz to 30 Hz. The welding current data is pretreated by wavelet filtering, mean filtering and normalization treatment. The SVR model is constructed by making use of the evolvement laws, the decision function can be achieved by training the SVR and the seam offset can be identified. The experimental results show that the precision of the offset identification can be greatly improved by modifying the SVR and applying mean filteringfrom the longitudinal direction. 展开更多
关键词 support vector regression machine data-dependent kernel function offset identification mean filtering
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Determination of reservoir induced earthquake using support vector machine and gaussian process regression
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作者 Pijush Samui Dookie Kim 《Applied Geophysics》 SCIE CSCD 2013年第2期229-234,237,共7页
The prediction of magnitude (M) of reservoir induced earthquake is an important task in earthquake engineering. In this article, we employ a Support Vector Machine (SVM) and Gaussian Process Regression (GPR) for... The prediction of magnitude (M) of reservoir induced earthquake is an important task in earthquake engineering. In this article, we employ a Support Vector Machine (SVM) and Gaussian Process Regression (GPR) for prediction of reservoir induced earthquake M based on reservoir parameters. Comprehensive parameter (E) and maximum reservoir depth] (H) are considered as inputs to the SVM and GPR. We give an equation for determination oil reservoir induced earthquake M. The developed SVM and GPR have been compared with] the Artificial Neural Network (ANN) method. The results show that the developed SVM and] GPR are efficient tools for prediction of reservoir induced earthquake M. / 展开更多
关键词 Reservoir induced earthquake earthquake magnitude support vector machine Gaussian Process regression PREDICTION
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Support vector machines approach to mean particle size of rock fragmentation due to bench blasting prediction 被引量:19
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作者 史秀志 周健 +2 位作者 吴帮标 黄丹 魏威 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第2期432-441,共10页
Aiming at the problems of the traditional method of assessing distribution of particle size in bench blasting, a support vector machines (SVMs) regression methodology was used to predict the mean particle size (X50... Aiming at the problems of the traditional method of assessing distribution of particle size in bench blasting, a support vector machines (SVMs) regression methodology was used to predict the mean particle size (X50) resulting from rock blast fragmentation in various mines based on the statistical learning theory. The data base consisted of blast design parameters, explosive parameters, modulus of elasticity and in-situ block size. The seven input independent variables used for the SVMs model for the prediction of X50 of rock blast fragmentation were the ratio of bench height to drilled burden (H/B), ratio of spacing to burden (S/B), ratio of burden to hole diameter (B/D), ratio of stemming to burden (T/B), powder factor (Pf), modulus of elasticity (E) and in-situ block size (XB). After using the 90 sets of the measured data in various mines and rock formations in the world for training and testing, the model was applied to 12 another blast data for validation of the trained support vector regression (SVR) model. The prediction results of SVR were compared with those of artificial neural network (ANN), multivariate regression analysis (MVRA) models, conventional Kuznetsov method and the measured X50 values. The proposed method shows promising results and the prediction accuracy of SVMs model is acceptable. 展开更多
关键词 rock fragmentation BLASTING mean panicle size (X50) support vector machines svms) PREDICTION
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采用改进遗传算法优化LS-SVM逆系统的外转子无铁心无轴承永磁同步发电机解耦控制 被引量:1
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作者 朱熀秋 沈良瑜 《中国电机工程学报》 EI CSCD 北大核心 2024年第5期2037-2046,I0032,共11页
为了实现外转子无铁心无轴承永磁同步发电机(outer rotor coreless bearingless permanent magnet synchronous generator,ORC-BPMSG)的精确控制,提出一种基于改进遗传算法(improved genetic algorithm,IGA)优化最小二乘支持向量机(leas... 为了实现外转子无铁心无轴承永磁同步发电机(outer rotor coreless bearingless permanent magnet synchronous generator,ORC-BPMSG)的精确控制,提出一种基于改进遗传算法(improved genetic algorithm,IGA)优化最小二乘支持向量机(least square support vector machine,LS-SVM)逆系统的解耦控制策略。首先,基于ORC-BPMSG的结构及工作原理,推导其数学模型,并分析其可逆性。其次,建立LS-SVM回归方程,并采用IGA优化LS-SVM的性能参数,从而训练得到逆系统。然后,将逆系统与原系统串接,形成伪线性系统,实现了ORC-BPMSG的线性化和解耦。最后,将提出的控制方法与传统LS-SVM逆系统控制方法进行对比仿真和实验。仿真和实验结果表明:所提出的控制策略可以较好地实现ORC-BPMSG输出电压和悬浮力、以及悬浮力之间的解耦控制。 展开更多
关键词 外转子无铁心无轴承永磁同步发电机 最小二乘支持向量机 逆系统 改进遗传算法 解耦控制
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Application of Support Vector Machine to Predict 5-year Survival Status of Patients with Nasopharyngeal Carcinoma after Treatment
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作者 华贻军 余舒 +5 位作者 洪明晃 杨晓伟 邱枋 郭灵 黄培钰 张国义 《The Chinese-German Journal of Clinical Oncology》 CAS 2006年第1期8-12,共5页
Objective: Support Vector Machine (SVM) is a machine-learning method, based on the principle of structural risk minimization, which performs well when applied to data outside the training set. In this paper, SVM wa... Objective: Support Vector Machine (SVM) is a machine-learning method, based on the principle of structural risk minimization, which performs well when applied to data outside the training set. In this paper, SVM was applied to predict 5-year survival status of patients with nasopharyngeal carcinoma (NPC) after treatment, we expect to find a new way for prognosis studies in cancer so as to assist right clinical decision for individual patient. Methods: Two modelling methods were used in the study; SVM network and a standard parametric logistic regression were used to model 5-year survival status. And the two methods were compared on a prospective set of patients not used in model construction via receiver operating characteristic (ROC) curve analysis. Results: The SVM1, trained with the 25 original input variables without screening, yielded a ROC area of 0.868, at sensitivity to mortality of 79.2% and the specificity of 94.5%. Similarly, the SVM2, trained with 9 input variables which were obtained by optimal input variable selection from the 25 original variables by logistic regression screening, yielded a ROC area of 0.874, at a sensitivity to mortality of 79.2% and the specificity of 95.6%, while the logistic regression yielded a ROC area of 0.751 at a sensitivity to mortality of 66.7% and gave a specificity of 83.5%. Conclusion: SVM found a strong pattern in the database predictive of 5-year survival status. The logistic regression produces somewhat similar, but better, results. These results show that the SVM models have the potential to predict individual patient's 5-year survival status after treatment, and to assist the clinicians for making a good clinical decision. 展开更多
关键词 support vector machine logistic regression nasopharyngeal carcinoma predictive model RADIOTHERAPY ROC curve
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基于RS-PCA-SVM的建筑项目安全预测模型
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作者 李永清 马亚冰 凤亚红 《合肥工业大学学报(自然科学版)》 CAS 北大核心 2024年第9期1243-1247,1261,共6页
为了减少建筑项目安全事故的发生,文章提出一种基于RS-PCA-SVM建筑项目安全组合预测模型,采用粗糙集理论(rough set,RS)对数据进行属性约简,剔除交叉和冗余信息,降低输入变量维数和计算复杂度,减少训练时间;利用主成分分析(principal co... 为了减少建筑项目安全事故的发生,文章提出一种基于RS-PCA-SVM建筑项目安全组合预测模型,采用粗糙集理论(rough set,RS)对数据进行属性约简,剔除交叉和冗余信息,降低输入变量维数和计算复杂度,减少训练时间;利用主成分分析(principal component analysis,PCA)法进行降维处理,除去贡献率较低的主成分,将剩余主成分作为支持向量机(support vector machine,SVM)的输入变量,并选择自适应权重粒子群优化算法(particle swarm optimization,PSO)优化SVM的参数,避免参数选择的盲目性。结果表明:该模型的平均预测准确率为93.78%,相比传统方法预测精度高、计算速度快。 展开更多
关键词 属性约简 主成分分析(PCA)法 支持向量机(svm) 预测模型
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基于SVM的干线输气管道泄漏压降速率信号识别
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作者 吴瑕 陈红环 +2 位作者 贾文龙 孙溢彬 任思波 《中国安全科学学报》 CAS CSCD 北大核心 2024年第6期119-126,共8页
为解决压缩机抽吸或截断阀截断形成的压降信号导致截断阀发生误关断,以及小孔泄漏因管道压降不显著导致截断阀不动作的问题,以某输气干线为对象建立仿真模型,获取压缩机抽吸、截断阀紧急截断及管道泄漏3类不同工况下的300组压降信号,根... 为解决压缩机抽吸或截断阀截断形成的压降信号导致截断阀发生误关断,以及小孔泄漏因管道压降不显著导致截断阀不动作的问题,以某输气干线为对象建立仿真模型,获取压缩机抽吸、截断阀紧急截断及管道泄漏3类不同工况下的300组压降信号,根据对点检测法计算出压降信号的压降速率值;以奇异值分解(SVD)法和极差归一化方法提取压降速率信号特征,采用支持向量机(SVM)法识别不同压降速率特征值信号,获取所对应的工况类型;针对SVM模型中的核函数参数与惩罚因子设置不合理,影响算法识别准确性的问题,采用教与学优化算法(TLBO)优化核函数参数与惩罚因子,建立干线输气管道泄漏信号智能识别的TLBO-SVM模型;应用该模型,分类识别该管道在3类工况下的300组模拟压降速率信号。结果表明:该模型对3类不同工况下压降速率信号的识别准确率为92.22%;对泄漏口径为50~125 mm,压降速率范围为0.01~0.07 MPa/min的小孔泄漏,识别准确率为96.67%。针对某干线管道的实际泄漏压降速率信号,TLBO-SVM识别到的准确率为100%。 展开更多
关键词 支持向量机(svm) 干线输气管道 压降速率信号 泄漏压力信号 截断阀
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不平衡数据下基于SVM增量学习的指挥信息系统状态监控方法
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作者 焦志强 易侃 +1 位作者 张杰勇 姚佩阳 《系统工程与电子技术》 EI CSCD 北大核心 2024年第3期992-1003,共12页
针对指挥信息系统历史状态样本有限的特点,基于支持向量机(support vector machines,SVM)设计了一种面向不平衡数据的SVM增量学习方法。针对系统正常/异常状态样本不平衡的情况,首先利用支持向量生成一部分新样本,然后通过分带的思想逐... 针对指挥信息系统历史状态样本有限的特点,基于支持向量机(support vector machines,SVM)设计了一种面向不平衡数据的SVM增量学习方法。针对系统正常/异常状态样本不平衡的情况,首先利用支持向量生成一部分新样本,然后通过分带的思想逐带产生分布更加均匀的新样本以调节原样本集的不平衡比。针对系统监控实时性要求高且在运行过程中会有新样本不断加入的特点,采用增量学习的方式对分类模型进行持续更新,在放松KKT(Karush-Kuhn-Tucker)更新触发条件的基础上,通过定义样本重要度并引入保留率和遗忘率的方式减少了增量学习过程中所需训练的样本数量。为了验证算法的有效性和优越性,实验部分在真实系统中获得的数据集以及UCI数据集中3类6组不平衡数据集中与现有的算法进行了对比。结果表明,所提算法能够有效实现对不平衡数据的增量学习,从而满足指挥信息系统状态监控的需求。 展开更多
关键词 指挥信息系统 系统监控 支持向量机 不平衡数据 增量学习
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