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改进的基于FFT pruning的窄带高分辨率频谱算法 被引量:3
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作者 王琰 万群 杨万麟 《计算机工程与应用》 CSCD 北大核心 2007年第26期54-55,141,共3页
提出一种改进的基于FFT pruning的窄带高分辨率频谱计算方法。该方法是对Sreenivas's FFT pruning算法和Nagai的利用频移变换的FFT pruning算法的推广。同时提出输出点分级思想,可实现任意窄带上非2的整数幂次频点输出。该算法比Sre... 提出一种改进的基于FFT pruning的窄带高分辨率频谱计算方法。该方法是对Sreenivas's FFT pruning算法和Nagai的利用频移变换的FFT pruning算法的推广。同时提出输出点分级思想,可实现任意窄带上非2的整数幂次频点输出。该算法比Sreenivas's FFT pruning算法具有更小的计算量和更简单的信号流图。 展开更多
关键词 FFT pruning 窄带 频移
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一种改进的FFT Pruning算法及其在塔康载波频率测量中的应用 被引量:1
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作者 彭大国 李治安 +2 位作者 李晓明 裴文林 牛诚旻 《南京邮电大学学报(自然科学版)》 北大核心 2015年第1期66-71,共6页
提出了一种改进的FFT Pruning算法。将Nagai提出的频移思想和Alves提出的辅助矩阵思想结合起来,对信号流图和辅助矩阵进行简化。对输出频点数与辅助矩阵列数的关系进行研究,降低了辅助矩阵的大小,并推导出辅助矩阵的表达式。将改进后的... 提出了一种改进的FFT Pruning算法。将Nagai提出的频移思想和Alves提出的辅助矩阵思想结合起来,对信号流图和辅助矩阵进行简化。对输出频点数与辅助矩阵列数的关系进行研究,降低了辅助矩阵的大小,并推导出辅助矩阵的表达式。将改进后的算法运用到塔康载波频率测量中,先用少点数的FFT进行频率粗搜索,再用改进的FFT Pruning算法进行频率精测。仿真结果表明,改进算法能在运算量不大的情况下实现对塔康载波频率的高精度测量。 展开更多
关键词 FFT pruning 辅助矩阵 塔康 频率测量
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Improved pruning algorithm for Gaussian mixture probability hypothesis density filter 被引量:8
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作者 NIE Yongfang ZHANG Tao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2018年第2期229-235,共7页
With the increment of the number of Gaussian components, the computation cost increases in the Gaussian mixture probability hypothesis density(GM-PHD) filter. Based on the theory of Chen et al, we propose an improved ... With the increment of the number of Gaussian components, the computation cost increases in the Gaussian mixture probability hypothesis density(GM-PHD) filter. Based on the theory of Chen et al, we propose an improved pruning algorithm for the GM-PHD filter, which utilizes not only the Gaussian components’ means and covariance, but their weights as a new criterion to improve the estimate accuracy of the conventional pruning algorithm for tracking very closely proximity targets. Moreover, it solves the end-less while-loop problem without the need of a second merging step. Simulation results show that this improved algorithm is easier to implement and more robust than the formal ones. 展开更多
关键词 Gaussian mixture probability hypothesis density(GM-PHD) filter pruning algorithm proximity targets clutter rate
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Improved adaptive pruning algorithm for least squares support vector regression 被引量:4
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作者 Runpeng Gao Ye San 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2012年第3期438-444,共7页
As the solutions of the least squares support vector regression machine (LS-SVRM) are not sparse, it leads to slow prediction speed and limits its applications. The defects of the ex- isting adaptive pruning algorit... As the solutions of the least squares support vector regression machine (LS-SVRM) are not sparse, it leads to slow prediction speed and limits its applications. The defects of the ex- isting adaptive pruning algorithm for LS-SVRM are that the training speed is slow, and the generalization performance is not satis- factory, especially for large scale problems. Hence an improved algorithm is proposed. In order to accelerate the training speed, the pruned data point and fast leave-one-out error are employed to validate the temporary model obtained after decremental learning. The novel objective function in the termination condition which in- volves the whole constraints generated by all training data points and three pruning strategies are employed to improve the generali- zation performance. The effectiveness of the proposed algorithm is tested on six benchmark datasets. The sparse LS-SVRM model has a faster training speed and better generalization performance. 展开更多
关键词 least squares support vector regression machine (LS- SVRM) pruning leave-one-out (LOO) error incremental learning decremental learning.
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A sparse algorithm for adaptive pruning least square support vector regression machine based on global representative point ranking 被引量:2
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作者 HU Lei YI Guoxing HUANG Chao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2021年第1期151-162,共12页
Least square support vector regression(LSSVR)is a method for function approximation,whose solutions are typically non-sparse,which limits its application especially in some occasions of fast prediction.In this paper,a... Least square support vector regression(LSSVR)is a method for function approximation,whose solutions are typically non-sparse,which limits its application especially in some occasions of fast prediction.In this paper,a sparse algorithm for adaptive pruning LSSVR algorithm based on global representative point ranking(GRPR-AP-LSSVR)is proposed.At first,the global representative point ranking(GRPR)algorithm is given,and relevant data analysis experiment is implemented which depicts the importance ranking of data points.Furthermore,the pruning strategy of removing two samples in the decremental learning procedure is designed to accelerate the training speed and ensure the sparsity.The removed data points are utilized to test the temporary learning model which ensures the regression accuracy.Finally,the proposed algorithm is verified on artificial datasets and UCI regression datasets,and experimental results indicate that,compared with several benchmark algorithms,the GRPR-AP-LSSVR algorithm has excellent sparsity and prediction speed without impairing the generalization performance. 展开更多
关键词 least square support vector regression(LSSVR) global representative point ranking(GRPR) initial training dataset pruning strategy SPARSITY regression accuracy
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Application of Pruning Algorithm on Voice Service Platform of Cow Disease Diagnosis Expert System 被引量:1
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作者 WANG Lishu 《Journal of Northeast Agricultural University(English Edition)》 CAS 2009年第4期47-51,共5页
Expert System (ES) is considered effective and efficient in agricultural production, as agricultural informationization becomes a main trend in agricultural development. ES, however, is applied unsatisfactorily in m... Expert System (ES) is considered effective and efficient in agricultural production, as agricultural informationization becomes a main trend in agricultural development. ES, however, is applied unsatisfactorily in most rural areas of China and it has considerably affected and restricted the development of the agricultural informationization. This paper proposed a solution to voice service system of ES, which was suitable for the information transmission, and it especially could help the peasants in remote regions obtain knowledge from ES through the voice service system. As for the disadvantages of massive knowledge data and slow deduction, in this system the classification method could be adopted based on the decision tree. Designing pruning algorithm to "trim off" the unrelated knowledge to the users in query course would simplify the structure of the decision tree and accelerate the speed of deduction before the inference engine deduced the knowledge required by users. 展开更多
关键词 pruning algorithm voice service platform cow disease Expert System
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A fuzzy logic resource allocation and memory cell pruning based artificial immune recognition system
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作者 邓泽林 谭冠政 +1 位作者 何锫 叶吉祥 《Journal of Central South University》 SCIE EI CAS 2014年第2期610-617,共8页
In order to improve the resource allocation mechanism of artificial immune recognition system(AIRS) and decrease the memory cells,a fuzzy logic resource allocation and memory cell pruning based AIRS(FPAIRS) is propose... In order to improve the resource allocation mechanism of artificial immune recognition system(AIRS) and decrease the memory cells,a fuzzy logic resource allocation and memory cell pruning based AIRS(FPAIRS) is proposed.In FPAIRS,the fuzzy logic is determined by a parameter,thus,the optimal fuzzy logics for different problems can be located through changing the parameter value.At the same time,the memory cells of low fitness scores are pruned to improve the classifier.This classifier was compared with other classifiers on six UCI datasets classification performance.The results show that the accuracies reached by FPAIRS are higher than or comparable to the accuracies of other classifiers,and the memory cells decrease when compared with the memory cells of AIRS.The results show that the algorithm is a high-performance classifier. 展开更多
关键词 artificial immune recognition system fuzzy logic memory cell pruning CLASSIFICATION
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Effects of different pruning ways on the sugar-decreasing matters of pumpkin (Cucurbita moschata) fruits during the ripeness
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作者 NI Shujun JIANG Xinmei +1 位作者 LIU Shouwei YU Xihong 《Journal of Northeast Agricultural University(English Edition)》 CAS 2007年第4期294-296,共3页
This experiment used pumpkin Longyuanlixiang as material to research the effect of different pruning ways with one branch, two branches, and three branches on the sugar-decreasing matters during the ripeness of pumpk... This experiment used pumpkin Longyuanlixiang as material to research the effect of different pruning ways with one branch, two branches, and three branches on the sugar-decreasing matters during the ripeness of pumpkin (Cucurbita moschata) fruits. The results showed that pectin contents of pumpkin fruits during the ripeness all increased at first and then dropped in every treatment. The pectin contents under the treatments of one branch and two branches reached the high apex after pollinated for 30 d as well as for 35 d under the treatment of three branches. Pentose and chromium contents of fruits had the same trend under different pruning ways and increased during the ripenes. Three kinds of sugar-decreasing matters contents under treatment of two branches were bigger than treatment of one branch, while treatment of three branches was the lowest. 展开更多
关键词 PUMPKIN pruning ways fruit ripeness sugar-decreasing matters
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基于无人机平台的电磁信号探测系统设计 被引量:1
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作者 周晓兰 刘建峰 +1 位作者 赵瑞娟 张正飞 《火力与指挥控制》 CSCD 北大核心 2024年第4期125-129,135,共6页
针对战场电磁环境机动监测需求,运用电磁信号感知与可视化分析技术,设计了一种基于无人机平台的战场电磁信号探测系统,构建了基于改进的FFT Pruning算法和Welch功率谱估计算法的频率中心计算模型,可实现复杂电磁环境下目标信号的频率、... 针对战场电磁环境机动监测需求,运用电磁信号感知与可视化分析技术,设计了一种基于无人机平台的战场电磁信号探测系统,构建了基于改进的FFT Pruning算法和Welch功率谱估计算法的频率中心计算模型,可实现复杂电磁环境下目标信号的频率、带宽、功率等参数检测,为部(分)队提供了机动、轻型、便捷的电磁信号监测手段。 展开更多
关键词 无人机 电磁信号监测 载频估算 FFT pruning
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关于VRML中物体间碰撞检测的研究 被引量:9
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作者 白伟冬 周之平 +1 位作者 张飒兵 吴介一 《计算机应用研究》 CSCD 北大核心 2004年第6期128-130,133,共4页
碰撞检测对于虚拟制造中的很多应用有着非常重要的意义 ,但是VRML只对碰撞检测提供了有限的支持。提出了一种碰撞检测系统来扩展VRML的功能 ,系统采用了K DOP算法对两个物体进行碰撞检测 。
关键词 碰撞检测 VRML 虚拟制造 K-DOP SWEEP and PRUNE
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一种更具拓扑稳定性的ISOMAP算法 被引量:20
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作者 邵超 黄厚宽 赵连伟 《软件学报》 EI CSCD 北大核心 2007年第4期869-877,共9页
ISOMAP算法能否被成功运用,很大程度上依赖于邻域大小的选取是否合适.然而,如何有效地选取合适的邻域大小,目前还是一个尚未解决的难题.根据“短路”边会途经相对的低密度区域这一特点,能够有效删除邻域图中可能存在的“短路”边,提出了... ISOMAP算法能否被成功运用,很大程度上依赖于邻域大小的选取是否合适.然而,如何有效地选取合适的邻域大小,目前还是一个尚未解决的难题.根据“短路”边会途经相对的低密度区域这一特点,能够有效删除邻域图中可能存在的“短路”边,提出了P-ISOMAP(pruned-ISOMAP)算法,这极大地削弱了ISOMAP算法对邻域大小的依赖程度,从而使其更具拓扑稳定性.由于避免了邻域大小难以有效选取的问题,P-ISOMAP算法能够更容易地对数据进行可视化.实验结果很好地验证了该算法的有效性. 展开更多
关键词 ISOMAP P—ISOMAP(pruned—ISOMAP) 邻域大小 拓扑稳定性 残差 核密度估计 局部密度
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原空间中最小二乘支持向量机的新算法 被引量:3
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作者 赵永平 孙健国 《系统工程与电子技术》 EI CSCD 北大核心 2009年第1期142-145,237,共5页
为了解决原空间中最小二乘支持向量机的解缺乏稀疏性的缺点,提出了Pruning法、MFCV法和IMFCV法并对BDFS法进行了修改和运用。对一个不含有奇异点的系统而言,Pruning法、BDFS法和MFCV法在一定程度上都能实现原空间中最小二乘支持向量机... 为了解决原空间中最小二乘支持向量机的解缺乏稀疏性的缺点,提出了Pruning法、MFCV法和IMFCV法并对BDFS法进行了修改和运用。对一个不含有奇异点的系统而言,Pruning法、BDFS法和MFCV法在一定程度上都能实现原空间中最小二乘支持向量机解的稀疏性。BDFS法无论是训练时间还是预测时间都比Pruning法短;和MFCV法比起来,虽然BDFS法的训练时间短,但比MFCV的预测时间长。对一个含有奇异点的系统而言,Pruning法几乎失去了效用;虽然BDFS和MFCV法的训练时间都比IMFCV法的训练时间短,但IMFCV法能成功抑制奇异点从而缩短预测时间。 展开更多
关键词 最小二乘支持向量机 pruning BDFS MFCV
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Multi-target tracking algorithm of boost-phase ballistic missile defense 被引量:2
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作者 Kangsheng Tian Feng Zhang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2013年第1期90-100,共11页
Considering the problem of multiple ballistic missiles tracking of boost-phase ballistic missile defense, a boost-phase tracking algorithm based on multiple hypotheses tracking (MHT) concept is proposed. This paper ... Considering the problem of multiple ballistic missiles tracking of boost-phase ballistic missile defense, a boost-phase tracking algorithm based on multiple hypotheses tracking (MHT) concept is proposed. This paper focuses on the tracking algo- rithm for hypothesis generation, hypothesis probability calculation, hypotheses reduction and pruning and other sectors. From an engineering point of view, a technique called the linear assignment problem (LAP) used in the implementation of M-best feasible hypotheses generation, the number of the hypotheses is relatively small compared with the total number that may exist in each scan, also the N-scan back pruning is used, the algorithm's efficiency and practicality have been improved. Monte Carlo simulation results show that the proposed algorithm can track the boost phase of multiple ballistic missiles and it has a good tracking performance compared with joint probability data association (JPDA). 展开更多
关键词 ballistic missile multiple hypotheses tracking (MHT) linear assignment problem (LAP) hypothesis pruning.
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基于多智能体深度强化学习的无人机路径规划 被引量:10
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作者 司鹏搏 吴兵 +2 位作者 杨睿哲 李萌 孙艳华 《北京工业大学学报》 CAS CSCD 北大核心 2023年第4期449-458,共10页
为解决多无人机(unmanned aerial vehicle, UAV)在复杂环境下的路径规划问题,提出一个多智能体深度强化学习UAV路径规划框架.该框架首先将路径规划问题建模为部分可观测马尔可夫过程,采用近端策略优化算法将其扩展至多智能体,通过设计UA... 为解决多无人机(unmanned aerial vehicle, UAV)在复杂环境下的路径规划问题,提出一个多智能体深度强化学习UAV路径规划框架.该框架首先将路径规划问题建模为部分可观测马尔可夫过程,采用近端策略优化算法将其扩展至多智能体,通过设计UAV的状态观测空间、动作空间及奖赏函数等实现多UAV无障碍路径规划;其次,为适应UAV搭载的有限计算资源条件,进一步提出基于网络剪枝的多智能体近端策略优化(network pruning-based multi-agent proximal policy optimization, NP-MAPPO)算法,提高了训练效率.仿真结果验证了提出的多UAV路径规划框架在各参数配置下的有效性及NP-MAPPO算法在训练时间上的优越性. 展开更多
关键词 无人机(unmanned aerial vehicle UAV) 复杂环境 路径规划 马尔可夫决策过程 多智能体近端策略优化算法(multi-agent proximal policy optimization MAPPO) 网络剪枝(network pruning NP)
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Feature Selection Based on Adaptive Fuzzy Membership Functions 被引量:1
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作者 XIE Yan-Tao SANG Nong ZHANG Tian-Xu 《自动化学报》 EI CSCD 北大核心 2006年第4期496-503,共8页
Neuro-fuzzy(NF)networks are adaptive fuzzy inference systems(FIS)and have been applied to feature selection by some researchers.However,their rule number will grow exponentially as the data dimension increases.On the ... Neuro-fuzzy(NF)networks are adaptive fuzzy inference systems(FIS)and have been applied to feature selection by some researchers.However,their rule number will grow exponentially as the data dimension increases.On the other hand,feature selection algorithms with artificial neural networks(ANN)usually require normalization of input data,which will probably change some characteristics of original data that are important for classification.To overcome the problems mentioned above,this paper combines the fuzzification layer of the neuro-fuzzy system with the multi-layer perceptron(MLP)to form a new artificial neural network.Furthermore,fuzzification strategy and feature measurement based on membership space are proposed for feature selection. Finally,experiments with both natural and artificial data are carried out to compare with other methods,and the results approve the validity of the algorithm. 展开更多
关键词 Membership function feature selection architecture pruning artificial neural networks
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关于多项式和的Waring问题(Ⅰ)
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作者 余刚 《数学年刊(A辑)》 CSCD 北大核心 1995年第3期381-388,共8页
设fk(x)为k次整系数多项式,最高次项系数为正且fk(x)-fk(0)没有固定因子.Rk(n)记整数n表为这样的一个二次、五个三次及一个k次多项式和的表法数,uk(n)记n表为两个二次、三个三次及一个k次多项式和的... 设fk(x)为k次整系数多项式,最高次项系数为正且fk(x)-fk(0)没有固定因子.Rk(n)记整数n表为这样的一个二次、五个三次及一个k次多项式和的表法数,uk(n)记n表为两个二次、三个三次及一个k次多项式和的表法数.本文得到了当k=3、4、5时,Rk(n)的渐近公式及当k≥2时uk(n)的渐近公式. 展开更多
关键词 渐近公式 WARING问题 圆法 pruning技术
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PRUNE2点突变影响前列腺癌DU145细胞增殖、凋亡、侵袭和迁移 被引量:1
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作者 曹达龙 朱文恺 +3 位作者 施国海 张海梁 王子良 叶定伟 《中国癌症杂志》 CAS CSCD 北大核心 2021年第6期441-446,共6页
背景与目的:PRUNE2是成神经细胞瘤的一个特异性预后相关基因,在调节成神经细胞瘤的细胞分化、增殖和侵袭方面发挥着重要作用。PRUNE2低表达与前列腺癌的不良预后密切相关。探讨PRUNE2点突变对前列腺癌DU145细胞增殖、凋亡、侵袭和迁移... 背景与目的:PRUNE2是成神经细胞瘤的一个特异性预后相关基因,在调节成神经细胞瘤的细胞分化、增殖和侵袭方面发挥着重要作用。PRUNE2低表达与前列腺癌的不良预后密切相关。探讨PRUNE2点突变对前列腺癌DU145细胞增殖、凋亡、侵袭和迁移的影响。方法:通过构建PRUNE2基因野生型和突变型过表达的重组载体并将其转染到DU145细胞中构建相应稳转株。利用细胞计数试剂盒-8(cell counting kit-8,CCK-8)实验和克隆形成实验检测细胞恶性增殖能力,通过细胞凋亡实验检测细胞凋亡能力,采用transwell小室法检测细胞侵袭和迁移能力。采用蛋白质印迹法(Western blot)检测蛋白的表达水平,通过免疫荧光和免疫共沉淀实验检测蛋白之间的相互作用。结果:转染突变型PRUNE2 E370K基因的DU145细胞恶性增殖、侵袭和迁移能力均较对照组显著增强,细胞凋亡率显著降低,差异有统计学意义(P<0.05)。PRUNE2与RhoA之间可以相互结合,但是PRUNE2 E370K突变体与RhoA之间的相关作用明显减弱。同时,PRUNE2 E370K突变体促进Rho通路下游ROCK蛋白和FAK蛋白的表达,促进与细胞增殖相关的Bcl-2和cyclin D1蛋白的表达,同时抑制与侵袭、迁移相关抑制蛋白E-cadherin的表达。结论:前列腺癌DU145细胞中PRUNE2基因点突变可以促进细胞增殖、侵袭和迁移,并抑制细胞凋亡。 展开更多
关键词 前列腺癌 PRUNE2 增殖 凋亡 侵袭 迁移
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Improved scheme to accelerate sparse least squares support vector regression
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作者 Yongping Zhao Jianguo Sun 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第2期312-317,共6页
The pruning algorithms for sparse least squares support vector regression machine are common methods, and easily com- prehensible, but the computational burden in the training phase is heavy due to the retraining in p... The pruning algorithms for sparse least squares support vector regression machine are common methods, and easily com- prehensible, but the computational burden in the training phase is heavy due to the retraining in performing the pruning process, which is not favorable for their applications. To this end, an im- proved scheme is proposed to accelerate sparse least squares support vector regression machine. A major advantage of this new scheme is based on the iterative methodology, which uses the previous training results instead of retraining, and its feasibility is strictly verified theoretically. Finally, experiments on bench- mark data sets corroborate a significant saving of the training time with the same number of support vectors and predictive accuracy compared with the original pruning algorithms, and this speedup scheme is also extended to classification problem. 展开更多
关键词 least squares support vector regression machine pruning algorithm iterative methodology classification.
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