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1.
提出一种稀疏局部Fisher判别分析(Sparsity Local Fisher Discriminant Analysis,SLFDA)。该算法在局部Fisher判别分析降维的基础上,通过平衡参数引入稀疏保持投影,在投影降维过程中保持了数据的全局几何结构和局部近邻信息。在UCI数据集和YaleB人脸数据集上的实验表明,该算法融合局部Fisher判别分析和稀疏保持投影的优点;与现有的半监督局部Fisher判别分析降维算法相比,该算法提高了基于最短欧氏距离的分类算法的精度。  相似文献   

2.
谈锐  陈秀宏 《计算机工程》2012,38(6):181-183
针对现有数据降维算法不能同时利用标记样本和无标记样本的问题,提出一种半监督局部保留投影降维方法。定义类间相似度和类内相似度,同时最大化类间分离度、最小化类内分离度,保持样本总体结构和局部结构,从而提高数据降维的效果。在人工数据集、UCI数据库和Olivetti人脸库中的测试结果表明,该方法的识别率较高。  相似文献   

3.
局部降维方法中存在仅考虑图像的相似信息,不能较好地保持图像的差异信息和像素间的空间结构等问题。为此,提出一种新的有监督降维方法,通过构建局部邻域相似图和局部差异图来刻画图像的局部结构。考虑到像素的空间结构,引入二维离散拉普拉斯图的光滑正则化来约束变换矩阵的平滑性。在Yale和ORL人脸数据库上进行实验验证,结果表明,该降维方法既能保持图像之间的局部结构信息,又能较好地保持图像间的差异信息及像素间的空间结构,并针对人脸图像可以有效提取出具有区分能力的低维特征,具有较高的识别精度。  相似文献   

4.
针对人脸识别应用中的高维数据图像以及欧氏距离不能准确体现样本间的相似度的问题,提出了一种基于马氏距离的局部边界Fisher分析(MLMFA)降维算法。该算法从现有的样本中学习得到一个马氏度量,然后在近邻选择以及新样本降维过程中用马氏距离作为相似性度量。同时,通过马氏度量构造出类内“相似”图和类间“代价”图来描述数据集的类内紧凑性和类间分离性。MLMFA很好地保持了数据集的局部结构。用YALE和FERET人脸库进行实验,MLMFA的最大识别率比传统基于欧氏距离算法的最大识别率平均分别提高了1.03%和6%。实验结果表明,算法MLMFA具有很好的分类和识别性能。  相似文献   

5.
针对高光谱图像分类中基于流形的降维方法进行了研究。提出一种改进的局部保持投影(LPP)方法即MLPP方法。该方法利用标签信息避免了传统LPP在邻接图构建中很难确定的邻域大小的选择问题,同时采用更能反映高维数据间相关性的统计特征量相关系数来衡量数据之间的相似程度。设计的权重矩阵既保持类内数据的几何结构,又最大化类间距离。而且MLPP不依赖任何参数和先验知识。在两个高光谱图像上的实验结果表明MLPP增加了不同光谱特征地物之间的可分性,在提高分类性能上明显优于其他传统的降维方法。  相似文献   

6.
薛寺中  谈锐  陈秀宏 《计算机应用》2012,32(8):2235-2244
为能有效捕捉数据的非线性特征,特提出一种新的非线性数据降维算法——核半监督局部保留投影(KSSLPP)。该方法利用标记样本的标记信息及所有训练样本的结构重新定义了类间相似度和类内相似度,然后将原始数据映射到高维核空间,在核空间中最大化类间分离度,最小化类内分离度。该方法在核空间保持了数据的局部结构和全局结构,以及数据的标签信息。在Olivetti人脸库和UCI数据库中的对比实验验证了该算法的有效性。  相似文献   

7.
提出一种双向二维加权局部保持投影算法(Two-directional Two-dimensional Weighted Locality Preserving Projections,(2D)2WLPP)用于语音特征提取后维度的降低,考虑到普通的二维降维算法只能从一个方向进行特征降维且所降至的维数选择非常受限,该方法能够从水平和垂直两个方向对语音矩阵进行降维处理,这样可以大大降低提取后的语音特征数目;考虑到不同投影向量对保持局部结构的重要程度不同,进而对各个特征赋予不同的权重系数.实验证明,该算法运算速度快,与已有的二维局部保持投影相比,获得了更高的识别率.  相似文献   

8.
基于改进结构保持数据降维方法的故障诊断研究   总被引:1,自引:0,他引:1  
韩敏  李宇  韩冰 《自动化学报》2021,47(2):338-348
传统基于核主成分分析(Kernel principal component analysis,KPCA)的数据降维方法在提取有效特征信息时只考虑全局结构保持而未考虑样本间的局部近邻结构保持问题,本文提出一种改进全局结构保持算法的特征提取与降维方法.改进的特征提取与降维方法将流形学习中核局部保持投影(Kernel loc...  相似文献   

9.
齐鸣鸣  向阳 《计算机应用》2014,34(6):1608-1612
为了解决现有判别分析算法对残缺和遮挡等外部干扰比较敏感的问题,从局部稀疏表示的角度,提出一种基于稀疏重构的判别分析(SDA)降维算法。该算法首先利用稀疏表示完成各个类内局部稀疏重构,然后通过非所在类内的样本均值完成各样本的类间局部稀疏重构,最后在降维过程中保持类间和类内的稀疏重构信息之比。在AR和UMIST人脸库人脸数据集上的实验结果表明,与基于图优化的Fisher分析(GbFA)算法和基于重构判别分析(RDA)算法相比,该算法提高了基于近邻分类的最高识别准确率2%~10%。  相似文献   

10.
已有的监督维数约简算法大都通过最大化类间离散度总和等相关手段选取判别能力较强的子空间,使得原始空间中距离较小的一些类易被忽略而在子空间中出现不同类的融合现象.为此,提出一种基于离散度平衡的降维算法——离散度平衡投影.该算法利用对称相对熵来衡量样本间的离散度,将对称相对熵与离散度平衡的概念结合,使得算法在降维过程中保持较大类间离散度的同时更加注重较小的类间离散度,以实现类间散度平衡的目的;为了充分使用现实生活中大量无标签样本,通过保持所有样本间拉普拉斯图结构进一步提出了半监督离散度平衡投影.对Soybean,Isolet,COIL20等标准数据集进行维数约简的实验结果表明,文中算法具有较好的降维效果.  相似文献   

11.
Abstract This paper describes an approach to the design of interactive multimedia materials being developed in a European Community project. The developmental process is seen as a dialogue between technologists and teachers. This dialogue is often problematic because of the differences in training, experience and culture between them. Conditions needed for fruitful dialogue are described and the generic model for learning design used in the project is explained.  相似文献   

12.
European Community policy and the market   总被引:1,自引:0,他引:1  
Abstract This paper starts with some reflections on the policy considerations and priorities which are shaping European Commission (EC) research programmes. Then it attempts to position the current projects which seek to capitalise on information and communications technologies for learning in relation to these priorities and the apparent realities of the marketplace. It concludes that while there are grounds to be optimistic about the contribution EC programmes can make to the efficiency and standard of education and training, they are still too technology driven.  相似文献   

13.
融合集成方法已经广泛应用在模式识别领域,然而一些基分类器实时性能稳定性较差,导致多分类器融合性能差,针对上述问题本文提出了一种新的基于多分类器的子融合集成分类器系统。该方法考虑在度量层融合层次之上通过对各类基多分类器进行动态选择,票数最多的类别作为融合系统中对特征向量识别的类别,构成一种新的自适应子融合集成分类器方法。实验表明,该方法比传统的分类器以及分类融合方法识别准确率明显更高,具有更好的鲁棒性。  相似文献   

14.
Development of software intensive systems (systems) in practice involves a series of self-contained phases for the lifecycle of a system. Semantic and temporal gaps, which occur among phases and among developer disciplines within and across phases, hinder the ongoing development of a system because of the interdependencies among phases and among disciplines. Such gaps are magnified among systems that are developed at different times by different development teams, which may limit reuse of artifacts of systems development and interoperability among the systems. This article discusses such gaps and a systems development process for avoiding them.  相似文献   

15.
This paper presents control charts models and the necessary simulation software for the location of economic values of the control parameters. The simulation program is written in FORTRAN, requires only 10K of main storage, and can run on most mini and micro computers. Two models are presented - one describes the process when it is operating at full capacity and the other when the process is operating under capacity. The models allow the product quality to deteriorate to a further level before an existing out-of-control state is detected, and they can also be used in situations where no prior knowledge exists of the out-of-control causes and the resulting proportion defectives.  相似文献   

16.
Going through a few examples of robot artists who are recognized worldwide, we try to analyze the deepest meaning of what is called “robot art” and the related art field definition. We also try to highlight its well-marked borders, such as kinetic sculptures, kinetic art, cyber art, and cyberpunk. A brief excursion into the importance of the context, the message, and its semiotics is also provided, case by case, together with a few hints on the history of this discipline in the light of an artistic perspective. Therefore, the aim of this article is to try to summarize the main characteristics that might classify robot art as a unique and innovative discipline, and to track down some of the principles by which a robotic artifact can or cannot be considered an art piece in terms of social, cultural, and strictly artistic interest. This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008  相似文献   

17.
Although there are many arguments that logic is an appropriate tool for artificial intelligence, there has been a perceived problem with the monotonicity of classical logic. This paper elaborates on the idea that reasoning should be viewed as theory formation where logic tells us the consequences of our assumptions. The two activities of predicting what is expected to be true and explaining observations are considered in a simple theory formation framework. Properties of each activity are discussed, along with a number of proposals as to what should be predicted or accepted as reasonable explanations. An architecture is proposed to combine explanation and prediction into one coherent framework. Algorithms used to implement the system as well as examples from a running implementation are given.  相似文献   

18.
This paper provides the author's personal views and perspectives on software process improvement. Starting with his first work on technology assessment in IBM over 20 years ago, Watts Humphrey describes the process improvement work he has been directly involved in. This includes the development of the early process assessment methods, the original design of the CMM, and the introduction of the Personal Software Process (PSP)SM and Team Software Process (TSP){SM}. In addition to describing the original motivation for this work, the author also reviews many of the problems he and his associates encountered and why they solved them the way they did. He also comments on the outstanding issues and likely directions for future work. Finally, this work has built on the experiences and contributions of many people. Mr. Humphrey only describes work that he was personally involved in and he names many of the key contributors. However, so many people have been involved in this work that a full list of the important participants would be impractical.  相似文献   

19.
基于复小波噪声方差显著修正的SAR图像去噪   总被引:4,自引:1,他引:3  
提出了一种基于复小波域统计建模与噪声方差估计显著性修正相结合的合成孔径雷达(Synthetic Aperture Radar,SAR)图像斑点噪声滤波方法。该方法首先通过对数变换将乘性噪声模型转化为加性噪声模型,然后对变换后的图像进行双树复小波变换(Dualtree Complex Wavelet Transform,DCWT),并对复数小波系数的统计分布进行建模。在此先验分布的基础上,通过运用贝叶斯估计方法从含噪系数中恢复原始系数,达到滤除噪声的目的。实验结果表明该方法在去除噪声的同时保留了图像的细节信息,取得了很好的降噪效果。  相似文献   

20.
Abstract  This paper considers some results of a study designed to investigate the kinds of mathematical activity undertaken by children (aged between 8 and 11) as they learned to program in LOGO. A model of learning modes is proposed, which attempts to describe the ways in which children used and acquired understanding of the programming/mathematical concepts involved. The remainder of the paper is concerned with discussing the validity and limitations of the model, and its implications for further research and curriculum development.  相似文献   

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