共查询到17条相似文献,搜索用时 62 毫秒
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飞行事故调查时缺失飞行参数的综合估计方法 总被引:4,自引:0,他引:4
分析了飞行事故时导致飞行参数缺失的几种因素,在介绍传统的基于参数变化率特性和基于参数间函数关系估计缺失飞行参数的方法后,重点研究了一种基于样本学习(神经网络和支持向量机)的缺失飞行参数的估计方法。仿真结果表明,当飞行参数间不存在确定的函数关系时,采用基于样本学习的飞行参数估计方法可行、有效。 相似文献
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寻找支持向量机(SVM)的最优参数是支持向量机研究领域的热点之一。2范数软间隔SVM(L2-SVM)将样本转化成线性可分,在原始单正则化参数L2-SVM的基础上,提出双正则化参数的L2-SVM,获得它的对偶形式,从而确定了最优化的目标函数。然后结合梯度法,提出了一种新的支持向量机参数选择的新方法(Doupenalty-Gradient)。实验使用了10个基准数据集,结果表明,Doupenalty-Gradient方法是可行且有效的。对于实验所用的样本,极大地改善了分类精度。 相似文献
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支持向量机C-SVM及υ-SVM是目前两种最为成熟的模型,但是从形式到算法、从参数特性到参数含义,它们都相互不同,这给人们的选择带来不便。为了将这两种SVM模型统一起来,提出一种新的模型Cυ-SVM,并依据统计学习理论,研究它的解的特性。给出了新模型解的完备性条件,找出它的解及其相应的算法,并指出了υ/C既是边界支持向量个数的上界,又是支持向量总数的下界。参数设置说明,新模型完全可以实现旧模型的所有功能,而新的算法更加方便诸如文本自动分类等领域的使用。 相似文献
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支持向量机作为一种基于结构风险最小化原则的统计学习理论,目前已广泛地应用于模式识别[1]、函数逼近[2]等研究领域,尤其是在小样本情况下相比传统统计学习理论体现了更好的泛化性能.选择无量纲参数作为支持向量机的特征向量,将其应用于发动机参数采集器的故障诊断中,结果表明,它对发动机参数采集器的故障模式具有很好的分类能力. 相似文献
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黄金山 《数字社区&智能家居》2014,(35)
作为二十一世纪的新兴技术,计算机互联网技术的发展和应用不仅为促进世界经济、科技一体化提供了必要的技术支持,而且对于促进各国各个生产领域的全面发展也具有较大的积极作用。但但随着网络技术的应用愈加普及和广泛,网络安全也成为了当下困扰网络用户的首要问题。该文通过引入网络安全态势预测法,在对该方法的概念以及基本原理进行说明的基础上,对基于支持向量机算法的网络安全态势预测模型的建立方法展开了深入研究,以求为维护网络安全提供有价值的参考意见。 相似文献
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Due to the growing demand on electricity, how to improve the efficiency of equipment in a thermal power plant has become one of the critical issues. Reports indicate that efficiency and availability are heavily dependant upon high reliability and maintainability. Recently, the concept of e-maintenance has been introduced to reduce the cost of maintenance. In e-maintenance systems, the intelligent fault detection system plays a crucial role for identifying failures. Data mining techniques are at the core of such intelligent systems and can greatly influence their performance. Applying these techniques to fault detection makes it possible to shorten shutdown maintenance and thus increase the capacity utilization rates of equipment. Therefore, this work proposes a support vector machines (SVM) based model which integrates a dimension reduction scheme to analyze the failures of turbines in thermal power facilities. Finally, a real case from a thermal power plant is provided to evaluate the effectiveness of the proposed SVM based model. Experimental results show that SVM outperforms linear discriminant analysis (LDA) and back-propagation neural networks (BPN) in classification performance. 相似文献
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基于支持向量机的遥感图像舰船目标识别方法 总被引:2,自引:0,他引:2
针对高分辨率遥感图像舰船目标识别问题,提出了一种基于支持向量机的舰船目标分类方法。支持向量机(SVM)是一类新型机器学习方法,基于结构风险最小化归纳原则,具有出色的学习能力。与传统的方法相比,支持向量机不但结构简单,而且技术性能特别是泛化能力明显提高。该文简要介绍了有关统计学习理论和支持向量机算法,将支持向量机应用于遥感图像舰船目标识别,并同传统的舰船识别方法进行了相关的对比实验,实验结果说明本文提出的分类器在识别性能上明显优于其它传统分类器,具有更高的识别性能率。 相似文献
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In the recent few decades there has been very significant developments in the theoretical understanding of Support vector machines (SVMs) as well as algorithmic strategies for implementing them, and applications of the approach to practical problems. SVMs introduced by Vapnik and others in the early 1990s are machine learning systems that utilize a hypothesis space of linear functions in a high dimensional feature space, trained with optimization algorithms that implements a learning bias derived from statistical learning theory. This paper reviews the state-of-the-art and focuses over a wide range of applications of SVMs in the field of hydrology. To use SVM aided hydrological models, which have increasingly extended during the last years; comprehensive knowledge about their theory and modelling approaches seems to be necessary. Furthermore, this review provides a brief synopsis of the techniques of SVMs and other emerging ones (hybrid models), which have proven useful in the analysis of the various hydrological parameters. Moreover, various examples of successful applications of SVMs for modelling different hydrological processes are also provided. 相似文献
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There are two well-known characteristics about text classification.One is that the dimension of the sample space is very high,while the number of examples available usually is very small.The other is that the example vectors are sparse.Meanwhile,we find existing support vector machines active learning approaches are subject to the influence of outliers.Based on these observations,this paper presents a new hybrid active learning approach.In this approach,to select the unlabelled example(s) to query,the learner takes into account both sparseness and high-di-mension characteristics of examples as well as its uncertainty about the examples‘‘ categorization.This way, the active learner needs less labeled examples,but still can get a good generalization performance more quickly than competing methods.Our empirical results indicate that this new approach is effective. 相似文献
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一种快速支持向量机增量学习算法 总被引:16,自引:0,他引:16
经典的支持向量机(SVM)算法在求解最优分类面时需求解一个凸二次规划问题,当训练样本数量很多时,算法的速度较慢,而且一旦有新的样本加入,所有的训练样本必须重新训练,非常浪费时间.为此,提出一种新的SVM快速增量学习算法.该算法首先选择那些可能成为支持向量的边界向量,以减少参与训练的样本数目;然后进行增量学习.学习算法是一个迭代过程,无需求解优化问题.实验证明,该算法不仅能保证学习机器的精度和良好的推广能力,而且算法的学习速度比经典的SVM算法快,可以进行增量学习. 相似文献
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Hong Qiao 《Pattern recognition》2007,40(9):2543-2549
Support vector machines (SVMs) are a new and important tool in data classification. Recently much attention has been devoted to large scale data classifications where decomposition methods for SVMs play an important role.So far, several decomposition algorithms for SVMs have been proposed and applied in practice. The algorithms proposed recently and based on rate certifying pair/set provide very attractive features compared with many other decomposition algorithms. They converge not only with finite termination but also in polynomial time. However, it is difficult to reach a good balance between low computational cost and fast convergence.In this paper, we propose a new simple decomposition algorithm based on a new philosophy on working set selection. It has been proven that the working set selected by the new algorithm is a rate certifying set. Further, compared with the existing algorithms based on rate certifying pair/set, our algorithm provides a very good feature in combination of lower computational complexity and faster convergence. 相似文献