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A fast stereoscopic video coding algorithm based on JMVM

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Science China(information Sciences) 2011年第6期54卷 1218-1226页

作者： DENG ZhiPin 1,2., JIA KeBin 1 , CHAN YuiLam 2., FU ChangHong 2.& SIU WanChi 2.1 department of electronic {2. & Control engineering, {4. university of Technology, {4. 10012.4} China 2.department of electronic {2. engineering, Hong Kong Polytechnic university, Hong Kong, China 1. department of electronic {2. & Control engineering Beijing University of Technology Beijing 100124 China2. Department of Electronic Information Engineering Hong Kong Polytechnic University Hong Kong China

In order to exploit the intra-view and inter-view dependencies in stereo video coding, a fast joint motion and disparity estimation algorithm is proposed in this paper. An efficient search strategy based on the motion-disparity constraint is developed, in which both the motion and disparity vectors can be obtained simultaneously with low complexity. Moreover, a credible initial predictive vector set is designed with the aid of the temporal and spatial neighboring blocks so that the coding efficiency can be further enhanced. The experimental results demonstrate that the proposed algorithm can reduce more than 96% coding time compared with the JMVM full search with a negligible quality drop.

关键词： H.2.4 stereoscopic video coding disparity estimation motion estimation

Sequence-based localization algorithm with improved correlation metric and dynamic centroid

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Science China(information Sciences) 2011年第11期54卷 2349-2358页

作者： YU Ying 1,JIANG ChunXiao 2.ZHAO XiaoJie 2.YUN LiJun 1,LI ZhiHua 2.& REN Yong 2. college of information,Yunnan Normal {2.,Kunming 650500,China 2.department of {4. engineering,Tsinghua {2.,beijing 100084.China 1. college of information Yunnan Normal University Kunming 650500 China2. Department of Electronic Engineering Tsinghua University Beijing 100084 China

Ecolocation (error controlling localization technique) is a novel sequence-based RF localization algorithm.A key feature of the Ecolocation algorithm is that it constructs a constraint table based on RSSI values and compares data between two ***,the definitions of the constraint and the centroid in the Ecolocation algorithm are imperfect,and result in poor localization *** improve the localization accuracy,a new algorithm based on weighted rank order correlation coefficient and dynamic centroid method is *** results indicate that compared with the Ecolocation,the localization accuracy and robustness of the new algorithm are distinctly raised.

关键词： WSNs (wireless sensor networks) localization sequences constraint table rank order correlation coefficient

CONVERGENCE PROPERTIES OF A MODIFIED BFGSALGORITHM FOR MINIMIZATION WITHARMIJO-GOLDSTEIN STEPLENGTHS

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Journal of Computational Mathematics 1999年第6期17卷 645-652页

作者： Nai-yang Deng Zheng-feng Li(department of Mathematics, beijing {2. engineering {4., beijing 100083,China) beijing Agr Engn Univ Dept Math Beijing 100083 Peoples R China

The line search strategy is crucial for an efficient unconstrained optimization algorithm. One of the reason why the Wolfe line searches is recommended lies in that it ensures positive definiteness of BFGS updates. When gradient information has to be obtained costly, the Armijo-Goldstein line searches may be preferred. To maintain positive difiniteness of BFGS updates based on the Armijo-Goldstein line searches, a slightly modified form of BFGS update is proposed by I.D. Coope and C.J. Price (Journal of Computational Mathematics, 13 (1995), 156-160), while its convergence properties is open up to now. This paper shows that the modified BFGS algorithm is globally and superlinearly convergent based on the Armijo-Goldstein line searches.

关键词： BFGS methods convergence superlinear convergence

A new method for adaptive color image filtering

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Chinese Science Bulletin 2000年第13期45卷 1230-1235页

作者： JIANG Gangyi, YU Mei & YU Bokang1. department, of information & {2. engineering, Hang/hou {4. of Commerce, Hangzhou 310035, China 2. department, of {2. engineering, Hangzhou institute of {2.s engineering, Hangzhou 310037, China 3. State Key Laboratory on Machine Perception, Peking {4., beijing 100871, China Correspondence should be addressed to Yu Mei department of information & {2. engineering Hangzhou University of Commerce Hangzhou China State Key Laboratory on Machine Perception Peking University Beijing China department of electronic {2. Hangzhou Institute of Electronics Engineering Hangzhou China

An adaptive color image filter (ACIF) is proposed in this note. Through analyzing noise corruption of color image, efficient locally adaptive filters are chosen for image enhancement. The proposed adaptive color image filter combines advantages of both nonlinear vector filters and linear filters, it attenuates noise and preserves edges and details very well. Experimental results show that the proposed filter performs better than vector median filter, directional-distance filter, directional-magnitude vector filter, adaptive nearest-neighbor filter, and α-trimmed mean filter.

关键词： color image noise analysis locally adaptive filters adaptive color image filter (ACIF).

Feature combination for classifying single-trial ECoG during motor imagery of different sessions

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Progress in Natural Science:Materials International 2007年第7期17卷 851-858页

作者： Wei Qingguo~(1,2. Meng Fei~1 Wang Yijun~1 Gao Xiaorong~1 Gao Shangkai~(1**) (1.department of Biomedical engineering,School of Medicine,Tsinghua {2.,beijing 100084.China 2.department of electronic engineering,School of information,Nanchang {2.,Nanchang 33002.,China) [a]department of Biomedical engineering School of Medicine TsinghuaUniversity Beijing China [b]department of electronic {2. School of Information Nanchang University Nanchang China

The input signals of brain-computer interfaces(BCIs)may be either scalp electroencephalogram(EEG)or electrocor- ticogram(ECoG)recorded from subdural *** make BCIs practical,the classifiers for discriminating different brain states must have the ability of session-to-session *** paper proposes an algorithm for classifying single-trial ECoG during motor imagery of different *** features,derived from two physiological phenomena,movement-related potentials(MRP)and event-related desynchronization(ERD),and extracted by common spatial subspace decomposition(CSSD)and waveform mean,are combined to per- form classification *** specific signal processing methods utilized are described in *** algorithm was successfully applied to Data SetⅠof BCI CompetitionⅢ,and achieved a classification accuracy of 91% on test set.

关键词： brain-computer interface(BCI) electrocorticogram(ECoG) session-to-session transfer feature combination movement-related potentials(MRP) event-related desynchronization(ERD)

Estimating fisheye camera parameters from homography

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Science China(information Sciences) 2012年第9期55卷 2119-2127页

作者： ZHU HaiJiang 1,YANG Ping 2.& LI ShiGang 3 1 School of information Science and Technology,beijing {2. of Chemical Technology,beijing,10002.,China 2.National Institute of Metrology,100013,beijing,China 3 department of Electrical and electronic engineering,Tottori {2.,680-8552.Koyama,Tottori,Japan 1. School of information Science and Technology Beijing University of Chemical Technology Beijing 100029 China2. National Institute of Metrology 100013 Beijing China3. Department of Electrical and Electronic Engineering Tottori University 680-8552 Koyama Tottori Japan

This paper presents a method to linearly estimate fisheye camera model parameters from the homography induced by the space plane between two fisheye *** homography is firstly calculated by using four feature points,instead of three points on the same line,in the fisheye *** the constraint on the model parameters of fisheye camera can be derived from the homography under the assumption that fisheye camera model is a polynomial *** the model parameters for different order polynomials are *** proposed technique requires only multiple fisheye images to include a planar scene and need not a priori knowledge of 3D coordinate of the planar *** results with synthetic data and real fisheye images demonstrate the validity of our *** method can also be extended to fisheye image of other planar scene excluding the planar calibration object.

关键词： homography parameter estimation fisheye camera

Detection and parameter estimation of multicomponent LFM signal based on the fractional Fourier transform

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Science in China(Series F) 2004年第2期47卷 184-198页

作者： QI Lin1, 2. TAO Ran1, ZHOU Siyong1 & WANG Yue1 1. department of electronic {2., beijing Institute of Technology, beijing 100081, China 2. School of information {2., Zhengzhou university, Zhengzhou 4.0052. China Correspondence should be addressed to QI Lin (email: qilin@***) 1. department of electronic {2. Beijing Institute of Technology 100081 Beijing China 2. School of information engineering Zhengzhou University 450052 Zhengzhou China

This paper presents a new method for the detection and parameter estimation of multicomponent LFM signals based on the fractional Fourier transform. For the optimization in the fractional Fourier domain, an algorithm based on Quasi-Newton method is proposed which consists of two steps of searching, leading to a reduction in computation without loss of accuracy. And for multicomponent signals, we further propose a signal separation technique in the fractional Fourier domain which can effectively suppress the interferences on the detection of the weak components brought by the stronger components. The statistical analysis of the estimate errors is also performed which perfects the method theoretically, and finally, simulation results are provided to show the validity of our method.

关键词： LFM signal parameter estimation fractional Fourier transform.

On the TOPS mode spaceborne SAR

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Science China(information Sciences) 2010年第2期53卷 367-378页

作者： BAI Xia 1 , SUN JinPing 2., HONG Wen 3 & MAO ShiYi 2.1 department of electronic {2., beijing Institute of Technology, beijing 100081, China 2.department of electronic {2., Beihang university , beijing 100191, China 3 Institute of electronics,Chinese Academy of Sciences, beijing 100190, China 1. department of electronic {2. Beijing Institute of Technology Beijing 100081 China2. Department of Electronic Engineering Beihang University Beijing 100191 China3. Institute of Electronics Chinese Academy of Sciences Beijing 100190 China

TOPS (terrain observation by progressive scans) is a recently proposed SAR mode for wide swath acquisition, which aims at achieving the same coverage and resolution as the SCAN mode besides creating scalloping-free images. In this paper, a general SAR imaging model used in TOPS and other SAR modes is introduced, where the antenna sweep rate, Doppler centroid rate, illumination time and azimuth resolution are described by a parameter defined as the "mode factor". After analyzing the characteristics of TOPS signal, an algorithm based on chirp-z transform is proposed, in which a new de-rotation function is used. Simulation results validate the proposed algorithm.

关键词： synthetic aperture radar acquisition mode TOPS

A Novel Low-bit-rate Speech Coding Based on Decomposition of the Pitch-cycle Waveform of the Linear Predictive Residual

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通信学报 1998年第5期19卷 39-44页

作者： Bao ChangchunAssociate professor of information engineering, {2. Polytechnic university, Ph.D, CIE senior member ({4. of electronic engineering, {2. Polytechnic university, {2. 10002.) Fan ChangxinProfessor of information Engineerin 北京工业大学电子工程系北京西安电子科技大学信息科学所陕西西安

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关键词：线性估计语音编码失量量化分解节圈波形