共查询到20条相似文献,搜索用时 171 毫秒
1.
引入基于局部保持能力判据的特征选择算法对融合离散余弦变换(DCT)和局部保持投影的人脸识别方法进行改进.首先对人脸图像进行DCT变换,得到DCT系数,然后以不同频率DCT系数的拉普拉斯值作为局部保持能力判据对DCT系数进行选择,最后对选出的DCT系数执行局部保持投影算法提取识别特征,在ORL人脸数据库上的实验结果证明了该方法的有效性. 相似文献
2.
提出一种特征融合的人脸识别新方法.该方法将人脸图像中少量的低频离散余弦变换(DCT)系数用作人脸的频域特征;把人脸图像规则地分成多个子块,计算每个子块的局部二值图(LBP)编码直方图.这些子块的LBP直方图连接成一个空域全局直方图,作为人脸的描述向量.这个描述向量经过PCA降维后作为人脸的LBP特征.DCT特征和LBP特征分别归一化,然后进行特征融合.在ORL人脸库上的实验显示了所提方法比单独采用DCT或LBP特征的人脸识别有较好的性能改善. 相似文献
3.
一种新的基于DCT变换的人脸表征 总被引:1,自引:0,他引:1
DCT变换是一种与KL变换非常相似的次最优变换算法.由于它独立于信号量,并且在维数下降、特征提取方面都非常接近经典的KL变换算法,因此DCT变换已经适用于模式识别领域.文章针对人脸图像,基于DCT变换,提出了一种融合整体DCT变换和分块加权DCT变换提取人脸图像的整体特征系数和局部特征系数,用于人脸表征的新方法.实验结果表明,本方法无论是在识别率还是在时间性能方面都优于传统的KL变换. 相似文献
4.
为了消除光照变化对人脸识别的影响,提出了一种新的基于小波的光照归一化算法。首先对人脸图像进行三级小波分解,获取低频和高频系数;接着对低频成分直方图均衡化,减弱光照的影响,同时对高频成分阈值去噪,再放大高频以增强图像边缘;最后进行逆小波变换,得到归一化后的人脸图像。在Yale B人脸库上的实验结果表明:本文方法可有效减弱光照变化对人脸识别的影响,显著地提高了人脸识别系统的识别率。 相似文献
5.
人脸识别过程中,针对二维主成分分析(2DPCA)算法在特征提取和数据降维上存在的问题,本文首先引入双向二维主成分分析(2D2DPCA)算法,该算法同时考虑图像行与列方向上的信息.考虑到人脸图像存在信息冗余而影响识别率的问题,于是本文提出一种基于小波加权双向二维主成分分析(WT-W2D2DPCA)的人脸识别算法.该算法首先采用二级小波分解对人脸图像进行预处理,提取其低频部分;然后根据人脸图像的特性,将低频部分进行奇偶分解,并引入加权思想,重组低频人脸图像,最后在ORL人脸数据库上进行双向二维主成分分析.实验结果表明,该方法不仅克服了传统2DPCA系数矩阵大的问题,而且得到了比传统的2DPCA、2D2DPCA算法更好的识别效果. 相似文献
6.
基于小波变换特征提取和神经网络分类的人脸识别 总被引:1,自引:0,他引:1
为提高人脸图像识别率,提出一种将小波分析与神经网络相结合的人脸识别方法。用二维离散小波变换函数对人脸图像进行二维离散小波变换,提取其低频系数作为人脸特征值,用三层神经网络进行分类、识别。实验证明,和单纯的小波方法及神经网络方法进行人脸识别相比,这种方法收敛步数少、用时短、具有较高的识别率。 相似文献
7.
为了提高人脸识别算法的识别率,提出了一种Gabor小波与监督局部线性嵌入(Supervised Locally Linear Embedding,SLLE)相结合的人脸特征提取算法。针对SLLE不能有效消除图像信息中冗余的高阶相关性,算法首先采用Gabor小波对人脸图像进行多方向、多分辨率滤波,提取图像在不同空间频率上的特征;然后采用监督的局部线性嵌入算法对该Gabor特征进行维数约简。在ORL和YALE人脸库上的实验显示,就算法有效提高了人脸识别的识别率。 相似文献
8.
9.
10.
将人工免疫及集合最近邻方法应用于人脸检测中,实现一种基于特征的人脸检测算法.首先对人脸图象进行多分辨率小波分解,用低频分量来描述人脸识别,实现数据压缩,并有效削弱光照的影响;然后对小波低频图象进行傅立叶变换,分析变换后的系数矩阵,取得人脸图象的特征向量;采用了人工免疫中的克隆选择算法,对一个人的多张不同表情的人脸图像进行训练,产生一个简约特征集合,用这个简约集合代表此人的人脸特征数据库;就待识别人脸而言,以待识别人脸到人脸数据库中各个人脸特征集合的集合最近邻作为识别结果.实验结果表明,人工免疫算法可以有效地获取训练样本的人脸特征集简约集合,再通过集合最近邻进行人脸识别,可以提高准确率. 相似文献
11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness. 相似文献
12.
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly. 相似文献
13.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。 相似文献
14.
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well. 相似文献
15.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation. 相似文献
16.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death. 相似文献
17.
Miao Maosheng 《华南师范大学学报(自然科学版)》2014,(6)
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula- 相似文献
18.
Yang Weitao 《华南师范大学学报(自然科学版)》2014,46(6):137-138
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re- 相似文献
19.
Bernard Kirtman 《华南师范大学学报(自然科学版)》2014,(6)
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that 相似文献
20.
《上海师范大学学报(自然科学版)》2014,(5):550
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with 相似文献