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Adaptive target and jamming recognition for the pulse doppler radar fuze based on a time-frequency joint feature and an online-updated naive bayesian classifier with minimal risk 被引量:6
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作者 Jian Dai Xin-hong Hao +2 位作者 Ze Li Ping Li Xiao-peng Yan 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2022年第3期457-466,共10页
This paper considers the problem of target and jamming recognition for the pulse Doppler radar fuze(PDRF).To solve the problem,the matched filter outputs of the PDRF under the action of target and jamming are analyzed... This paper considers the problem of target and jamming recognition for the pulse Doppler radar fuze(PDRF).To solve the problem,the matched filter outputs of the PDRF under the action of target and jamming are analyzed.Then,the frequency entropy and peak-to-peak ratio are extracted from the matched filter output of the PDRF,and the time-frequency joint feature is constructed.Based on the time-frequency joint feature,the naive Bayesian classifier(NBC)with minimal risk is established for target and jamming recognition.To improve the adaptability of the proposed method in complex environments,an online update process that adaptively modifies the classifier in the duration of the work of the PDRF is proposed.The experiments show that the PDRF can maintain high recognition accuracy when the signal-to-noise ratio(SNR)decreases and the jamming-to-signal ratio(JSR)increases.Moreover,the applicable analysis shows that he ONBCMR method has low computational complexity and can fully meet the real-time requirements of PDRF. 展开更多
关键词 Pulse Doppler radar fuze(PDRF) Target and jamming recognition Time-frequency joint feature Online-update naive Bayesian classifier minimal risk(ONBCMR)
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Operation and Force Analysis of the Guide Wire in a Minimally Invasive Vascular Interventional Surgery Robot System 被引量:5
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作者 YANG Xue WANG Hongbo +1 位作者 SUN Li YU Hongnian 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2015年第2期249-257,共9页
To develop a robot system for minimally invasive surgery is significant,however the existing minimally invasive surgery robots are not applicable in practical operations,due to their limited functioning and weaker per... To develop a robot system for minimally invasive surgery is significant,however the existing minimally invasive surgery robots are not applicable in practical operations,due to their limited functioning and weaker perception.A novel wire feeder is proposed for minimally invasive vascular interventional surgery.It is used for assisting surgeons in delivering a guide wire,balloon and stenting into a specific lesion location.By contrasting those existing wire feeders,the motion methods for delivering and rotating the guide wire in blood vessel are described,and their mechanical realization is presented.A new resistant force detecting method is given in details.The change of the resistance force can help the operator feel the block or embolism existing in front of the guide wire.The driving torque for rotating the guide wire is developed at different positions.Using the CT reconstruction image and extracted vessel paths,the path equation of the blood vessel is obtained.Combining the shapes of the guide wire outside the blood vessel,the whole bending equation of the guide wire is obtained.That is a risk criterion in the delivering process.This process can make operations safer and man-machine interaction more reliable.A novel surgery robot for feeding guide wire is designed,and a risk criterion for the system is given. 展开更多
关键词 minimally invasive wire feeder force analysis moment of inertia risk criterion
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China Prevents and Minimizes Financial Risks──Memorandum
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《China's Foreign Trade》 1999年第5期20-20,共1页
关键词 In China Prevents and Minimizes Financial risks Memorandum
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Research and Enlightenment of EU Drug Risk Management Plan
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作者 Yang Yu Shi Yu +1 位作者 Hu Rongbo Tian Lijuan 《Asian Journal of Social Pharmacy》 2021年第1期23-30,共8页
Objective To study the origin and development,framework and content of the EU-RMP(European Drug Risk Management Plan)so as to provide a reference for China’s drug risk management plan(RMP).Methods Literature research... Objective To study the origin and development,framework and content of the EU-RMP(European Drug Risk Management Plan)so as to provide a reference for China’s drug risk management plan(RMP).Methods Literature research and comparative research were used in this paper.Through searching Chinese and foreign literature,the website of European Medicines Agency(EMA)and the Guideline on Good Pharmacovigilance Practices(GVP),in-depth understanding of the EU-RMP content and requirements,some lessons were extracted for our reference.Results and Conclusion All departments should cooperate closely in the preparation of RMP in China.Then,the risk control measures should be further enriched to reduce the risks.Besides,the rules for implementing RMP should be clarified to promote the risk management of the whole life cycle of drugs and maintain the safety of patients’medication. 展开更多
关键词 risk management plan risk minimization EU
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SVD-LSSVM and its application in chemical pattern classification 被引量:2
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作者 TAO Shao-hui CHEN De-zhao HU Wang-ming 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第11期1942-1947,共6页
Pattern classification is an important field in machine learning; least squares support vector machine (LSSVM) is a powerful tool for pattern classification. A new version of LSSVM, SVD-LSSVM, to save time of selectin... Pattern classification is an important field in machine learning; least squares support vector machine (LSSVM) is a powerful tool for pattern classification. A new version of LSSVM, SVD-LSSVM, to save time of selecting hyper parameters for LSSVM is proposed. SVD-LSSVM is trained through singular value decomposition (SVD) of kernel matrix. Cross validation time of selecting hyper parameters can be saved because a new hyper parameter, singular value contribution rate (SVCR), replaces the penalty factor of LSSVM. Several UCI benchmarking data and the Olive classification problem were used to test SVD-LSSVM. The result showed that SVD-LSSVM has good performance in classification and saves time for cross validation. 展开更多
关键词 Pattern classification Structural risk minimization Least squares support vector machine (LSSVM) Hyper pa-rameter selection Cross validation Singular value decomposition (SVD)
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Research on Natural Gas Short-Term Load Forecasting Based on Support Vector Regression 被引量:1
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作者 刘涵 刘丁 +1 位作者 郑岗 梁炎明 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2004年第5期732-736,共5页
Natural gas load forecasting is a key process to the efficient operation of pipeline network. An accurate forecast is required to guarantee a balanced network operation and ensure safe gas supply at a minimum cost.Mac... Natural gas load forecasting is a key process to the efficient operation of pipeline network. An accurate forecast is required to guarantee a balanced network operation and ensure safe gas supply at a minimum cost.Machine learning techniques have been increasingly applied to load forecasting. A novel regression technique based on the statistical learning theory, support vector machines (SVM), is investigated in this paper for natural gas shortterm load forecasting. SVM is based on the principle of structure risk minimization as opposed to the principle of empirical risk minimization in conventional regression techniques. Using a data set with 2 years load values we developed prediction model using SVM to obtain 31 days load predictions. The results on city natural gas short-term load forecasting show that SVM provides better prediction accuracy than neural network. The software package natural gas pipeline networks simulation and load forecasting (NGPNSLF) based on support vector regression prediction has been developed, which has also been applied in practice. 展开更多
关键词 structure risk minimization support vector machines support vectorregression load forecasting neural network
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Yarn Properties Prediction Based on Machine Learning Method 被引量:1
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作者 杨建国 吕志军 李蓓智 《Journal of Donghua University(English Edition)》 EI CAS 2007年第6期781-786,共6页
Although many works have been done to construct prediction models on yarn processing quality,the relation between spinning variables and yarn properties has not been established conclusively so far.Support vector mach... Although many works have been done to construct prediction models on yarn processing quality,the relation between spinning variables and yarn properties has not been established conclusively so far.Support vector machines(SVMs),based on statistical learning theory,are gaining applications in the areas of machine learning and pattern recognition because of the high accuracy and good generalization capability.This study briefly introduces the SVM regression algorithms,and presents the SVM based system architecture for predicting yarn properties.Model selection which amounts to search in hyper-parameter space is performed for study of suitable parameters with grid-research method.Experimental results have been compared with those of artificial neural network(ANN)models.The investigation indicates that in the small data sets and real-life production,SVM models are capable of remaining the stability of predictive accuracy,and more suitable for noisy and dynamic spinning process. 展开更多
关键词 machine learning support vector machines artificial neural networks structure risk minimization yarn quality prediction
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Insiders' Hedging for Jump Diffusion Processes with Applications to Index Tracking
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作者 苏小囡 王伟 王文胜 《Journal of Donghua University(English Edition)》 EI CAS 2011年第6期571-575,共5页
The hedging problem for insiders is very important in the financial market.The locally risk minimizing hedging was adopted to solve this problem.Since the market was incomplete,the minimal martingale measure was chose... The hedging problem for insiders is very important in the financial market.The locally risk minimizing hedging was adopted to solve this problem.Since the market was incomplete,the minimal martingale measure was chosen as the equivalent martingale measure.By the F-S decomposition,the expression of the locally risk minimizing strategy was presented.Finally,the local risk minimization was applied to index tracking and its relationship with tracking error variance (TEV)-minimizing strategy was obtained. 展开更多
关键词 jump diffusion processes local risk minimization insiders’ hedging index tracking
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Accelerated Stochastic Peaceman–Rachford Method for Empirical Risk Minimization
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作者 Jian-Chao Bai Feng-Miao Bian +1 位作者 Xiao-Kai Chang Lin Du 《Journal of the Operations Research Society of China》 EI CSCD 2023年第4期783-807,共25页
This work is devoted to studying an accelerated stochastic Peaceman–Rachford splitting method(AS-PRSM)for solving a family of structural empirical risk minimization problems.The objective function to be optimized is ... This work is devoted to studying an accelerated stochastic Peaceman–Rachford splitting method(AS-PRSM)for solving a family of structural empirical risk minimization problems.The objective function to be optimized is the sum of a possibly nonsmooth convex function and a finite sum of smooth convex component functions.The smooth subproblem in AS-PRSM is solved by a stochastic gradient method using variance reduction technique and accelerated techniques,while the possibly nonsmooth subproblem is solved by introducing an indefinite proximal term to transform its solution into a proximity operator.By a proper choice for the involved parameters,we show that AS-PRSM converges in a sublinear convergence rate measured by the function value residual and constraint violation in the sense of expectation and ergodic.Preliminary experiments on testing the popular graph-guided fused lasso problem in machine learning and the 3D CT reconstruction problem in medical image processing show that the proposed AS-PRSM is very efficient. 展开更多
关键词 Empirical risk minimization Convex optimization Stochastic Peaceman-Rachford method Indefinite proximal term Complexity
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An oracle inequality for regularized risk minimizers with strongly mixing observations
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作者 Feilong CAO Xing XING 《Frontiers of Mathematics in China》 SCIE CSCD 2013年第2期301-315,共15页
We establish a general oracle inequality for regularized risk minimizers with strongly mixing observations, and apply this inequality to support vector machine (SVM) type algorithms. The obtained main results extend... We establish a general oracle inequality for regularized risk minimizers with strongly mixing observations, and apply this inequality to support vector machine (SVM) type algorithms. The obtained main results extend the previous known results for independent and identically distributed samples to the case of exponentially strongly mixing observations. 展开更多
关键词 Oracle inequality exponentially strongly mixing regularized risk minimizer
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Improved twin support vector machine 被引量:6
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作者 TIAN YingJie JU XuChan +1 位作者 QI ZhiQuan SHI Yong 《Science China Mathematics》 SCIE 2014年第2期417-432,共16页
We improve the twin support vector machine(TWSVM)to be a novel nonparallel hyperplanes classifier,termed as ITSVM(improved twin support vector machine),for binary classification.By introducing the diferent Lagrangian ... We improve the twin support vector machine(TWSVM)to be a novel nonparallel hyperplanes classifier,termed as ITSVM(improved twin support vector machine),for binary classification.By introducing the diferent Lagrangian functions for the primal problems in the TWSVM,we get an improved dual formulation of TWSVM,then the resulted ITSVM algorithm overcomes the common drawbacks in the TWSVMs and inherits the essence of the standard SVMs.Firstly,ITSVM does not need to compute the large inverse matrices before training which is inevitable for the TWSVMs.Secondly,diferent from the TWSVMs,kernel trick can be applied directly to ITSVM for the nonlinear case,therefore nonlinear ITSVM is superior to nonlinear TWSVM theoretically.Thirdly,ITSVM can be solved efciently by the successive overrelaxation(SOR)technique or sequential minimization optimization(SMO)method,which makes it more suitable for large scale problems.We also prove that the standard SVM is the special case of ITSVM.Experimental results show the efciency of our method in both computation time and classification accuracy. 展开更多
关键词 support vector machine twin support vector machine nonparallel structural risk minimization CLASSIFICATION
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The key theorem and the bounds on the rate of uniform convergence of learning theory on Sugeno measure space 被引量:16
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作者 HA Minghu LI Yan +1 位作者 LI Jia TIAN Dazeng 《Science in China(Series F)》 2006年第3期372-385,共14页
Some properties of Sugeno measure are further discussed, which is a kind of typical nonadditive measure. The definitions and properties of gλ random variable and its distribution function, expected value, and varianc... Some properties of Sugeno measure are further discussed, which is a kind of typical nonadditive measure. The definitions and properties of gλ random variable and its distribution function, expected value, and variance are then presented. Markov inequality, Chebyshev's inequality and the Khinchine's Law of Large Numbers on Sugeno measure space are also proven. Furthermore, the concepts of empirical risk functional, expected risk functional and the strict consistency of ERM principle on Sugeno measure space are proposed. According to these properties and concepts, the key theorem of learning theory, the bounds on the rate of convergence of learning process and the relations between these bounds and capacity of the set of functions on Sugeno measure space are given. 展开更多
关键词 Sugeno measure the empirical risk minimization principle the key theorem the bounds on the rate of uniform convergence.
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Markov decision processes associated with two threshold probability criteria
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作者 Masahiko SAKAGUCHI Yoshio OHTSUBO 《控制理论与应用(英文版)》 EI CSCD 2013年第4期548-557,共10页
This paper deals with Markov decision processes with a target set for nonpositive rewards. Two types of threshold probability criteria are discussed. The first criterion is a probability that a total reward is not gre... This paper deals with Markov decision processes with a target set for nonpositive rewards. Two types of threshold probability criteria are discussed. The first criterion is a probability that a total reward is not greater than a given initial threshold value, and the second is a probability that the total reward is less than it. Our first (resp. second) optimizing problem is to minimize the first (resp. second) threshold probability. These problems suggest that the threshold value is a permissible level of the total reward to reach a goal (the target set), that is, we would reach this set over the level, if possible. For the both problems, we show that 1) the optimal threshold probability is a unique solution to an optimality equation, 2) there exists an optimal deterministic stationary policy, and 3) a value iteration and a policy space iteration are given. In addition, we prove that the first (resp. second) optimal threshold probability is a monotone increasing and right (resp. left) continuous function of the initial threshold value and propose a method to obtain an optimal policy and the optimal threshold probability in the first problem by using them in the second problem. 展开更多
关键词 Markov decision process Minimizing risk model Threshold probability Policy space iteration
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Hierarchical Polytope ARTMAP for Supervised Learning
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作者 廖鑫鹏 吴永强 韩崇昭 《Journal of Computer Science & Technology》 SCIE EI CSCD 2010年第5期1071-1082,共12页
The recent Polytope ARTMAP(PTAM) suggests that irregular polytopes are more flexible than the predefined category geometries to approximate the borders among the desired output predictions.However,category expansion... The recent Polytope ARTMAP(PTAM) suggests that irregular polytopes are more flexible than the predefined category geometries to approximate the borders among the desired output predictions.However,category expansion and adjustment steps without statistical information make PTAM not robust to noise and category overlap.In order to push the learning problem towards Structural Risk Minimization(SRM),this paper proposes Hierarchical Polytope ARTMAP (HPTAM) to use a hierarchical structure with different levels,which are determined by the complexity of regions incorporating the input pattern.Besides,overlapping of simplexes from the same desired prediction is designed to reduce category proliferation.Although HPTAM is still inevitably sensible to noisy outliers in the presence of noise,main experimental results show that HPTAM can achieve a balance between representation error and approximation error,which ameliorates the overall generalization capabilities. 展开更多
关键词 structural risk minimization polytope ARTMAP hierarchical structure representation error approximation error
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