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考虑均值的滤除脉冲噪声的自适应非线性滤波 被引量:1
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作者 贾惠珍 王同罕 《计算机工程与应用》 CSCD 北大核心 2011年第36期208-210,241,共4页
针对脉冲噪声滤除,提出一种基于均值的自适应非线性滤波。其算法思想是先进行噪声检测并生成相应的噪声标志矩阵,随后扫描噪声标志矩阵,对信号点则直接输出,而噪声点则根据窗口内噪声点个数自适应选择滤波窗口,接着生成一个由滤波窗口... 针对脉冲噪声滤除,提出一种基于均值的自适应非线性滤波。其算法思想是先进行噪声检测并生成相应的噪声标志矩阵,随后扫描噪声标志矩阵,对信号点则直接输出,而噪声点则根据窗口内噪声点个数自适应选择滤波窗口,接着生成一个由滤波窗口各像素灰度与相应均值之差形成的差别矩阵,并赋予差别矩阵各元素不同的权重,最后返回加权后差别矩阵中最小值的位置,并用该像素的灰度取代噪声点。噪声点滤除算法,其实质是找出一个空间位置上离噪声点最近且最接近均值的像素的灰度来取代噪声点。通过实验,该方法具有更好的综合滤波性能。 展开更多
关键词 脉冲噪声 噪声标志矩 自适应 均值 差别阵 加权
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No-relationship Between Impossibility of Faster-Than-Light Quantum Communication and Distinction of Ensembles with the Same Density Matrix 被引量:1
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作者 WANG Chuan LONG Gui-Lu SUN Yang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第4X期622-624,共3页
It has been claimed in the literature that impossibility of faster-than-light quantum communication has an origin of indistinguishability of ensembles with the same density matrix. We show that the two concepts are no... It has been claimed in the literature that impossibility of faster-than-light quantum communication has an origin of indistinguishability of ensembles with the same density matrix. We show that the two concepts are not related.We argue that even with an ideal single-atom-precision measurement, it is generally impossible to produce two ensembles with exactly the same density matrix; or to produce ensembles with the same density matrix, classical communication is necessary. Hence the impossibility of faster-than-light communication does not imply the indistinguishability of ensembles with the same density matrix. 展开更多
关键词 faster-than-light communication distinction of ensembles density matrix
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A matching algorithm based on hybrid matrices consisting of reference differences and disparities
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作者 管业鹏 顾伟康 《Journal of Zhejiang University Science》 CSCD 2004年第7期796-802,共7页
Unique correct correspondence cannot be obtained only by use of gray correlation technique, which describes gray similar degree of feature points between the left and right images too unilaterally. The gray correlatio... Unique correct correspondence cannot be obtained only by use of gray correlation technique, which describes gray similar degree of feature points between the left and right images too unilaterally. The gray correlation technique is adopted to extract gray correlation peaks as a coarse matching set called multi-peak set. The disparity gradient limited constraint is utilized to optimize the multi-peak set. Unique match will be obtained by calculating the correlation of hybrid matrices consisting of reference differences and disparities from the multi-peak set. Two of the known corresponding points in the left and right images, respectively, are set as a pair of reference points to determine search direction and search scope at first. After the unique correspondence is obtained by calculating the correlation of the hybrid matrices from the multi-peak set, the obtained match is regarded as a new reference point till all feature points in the left (or right) image have been processed. Experimental results proved that the proposed algorithm was feasible and accurate. 展开更多
关键词 Gray correlation Multi-peak set Reference difference DISPARITY Hybrid matrix
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An infrared human face recognition method based on 2DPCA
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作者 刘侠 李廷军 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2009年第2期265-268,共4页
Aimed at the problems of infrared image recognition under varying illumination,face disguise,etc.,we bring out an infrared human face recognition algorithm based on 2DPCA.The proposed algorithm can work out the covari... Aimed at the problems of infrared image recognition under varying illumination,face disguise,etc.,we bring out an infrared human face recognition algorithm based on 2DPCA.The proposed algorithm can work out the covariance matrix of the training sample easily and directly;at the same time,it costs less time to work out the eigenvector.Relevant experiments are carried out,and the result indicates that compared with the traditional recognition algorithm,the proposed recognition method is swift and has a good adaptability to the changes of human face posture. 展开更多
关键词 infrared image face recognition feature sub-space K-L transformation
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Orthogonal arrays obtained by generalized difference matrices with g levels 被引量:11
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作者 ZHANG YingShan LI WeiGuo +1 位作者 MAO ShiSong ZHENG ZhongGuo 《Science China Mathematics》 SCIE 2011年第1期133-143,共11页
Nowadays orthogonal arrays play important roles in statistics, computer science, coding theory and cryptography. The usual difference matrices are essential for the construction for many mixed orthogonal arrays. But t... Nowadays orthogonal arrays play important roles in statistics, computer science, coding theory and cryptography. The usual difference matrices are essential for the construction for many mixed orthogonal arrays. But there are also orthogonal arrays which cannot be obtained by the usual difference matrices, such as mixed orthogonal arrays of run size 60. In order to construct these mixed orthogonal arrays, a class of special so-called generalized difference matrices were discovered by Zhang (1989,1990,1993,2006) from the orthogonal decompositions of projection matrices. In this article, an interesting equivalent relationship between orthogonal arrays and the generalized difference matrices is presented and proved. As an application, a lot of new orthogonal arrays of run size 60 have been constructed. 展开更多
关键词 mixed-level orthogonal arrays generalized difference matrices projection matrices permutation matrices
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A novel joint navigation state error discriminator based on iterative maximum likelihood estimation 被引量:2
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作者 WANG YongQing LUO Yu +1 位作者 WANG Pai WU SiLiang 《Science China Chemistry》 SCIE EI CAS CSCD 2015年第12期115-128,共14页
To break through the limitations of traditional discriminators used in vector tracking loops, this paper presents an iterative maximum likelihood estimation(IMLE) method for extracting navigation state errors from mul... To break through the limitations of traditional discriminators used in vector tracking loops, this paper presents an iterative maximum likelihood estimation(IMLE) method for extracting navigation state errors from multi-satellite signals. The IMLE method takes into account both computational cost and estimation accuracy. The associated gradient vector and Hessian matrix of the MLE cost function are derived. The characteristics of the proposed joint discriminator are analyzed based on the properties of the MLE cost function,gradient vector, and Hessian matrix. The effectiveness of IMLE is verified by Monte Carlo simulation. 展开更多
关键词 global navigation satellite system (GNSS) iterative maximum likelihood estimation (IMLE) jointnavigation state error discriminator Cramer-Rao bound (CRB) vector tracking loop
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