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Video-based facial animation with detailed appearance texture

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Progress in Natural science:Materials International 2006年第3期16卷 297-306页

作者： WANG Jin, SUN Hanqiu and PENG Qunsheng (department of computer {2. & technology, Xuzhou Normal university, Xuzhou 2.1009, china State Key Laboratory of CAD & CG, Zhejiang university, Zhejiang 31002., china department of computer {2. & Engineering, CUHK Shatin, N.T., Hong Kong) [a]department of computer {2. & technology Xuzhou China [b]State Key Laboratory of CAD & CG Zhejiang University Zhejiang China [c]department of computer {2. & Engineering CHUK shatin N.T. Hong Kong

Facial shape transformation described by facial animation parameters (FAPs) involves the dynamic movement or deformation of eyes, brows, mouth, and lips, while detailed facial appearance concerns the facial textures such as creases, wrinkles, etc. Video-based facial animation exhibits not only facial shape transformation but also detailed appearance updates. In this paper, a novel algorithm for effectively extracting FAPs from video is proposed. Our system adopts the ICA-enforced direct appearance model (DAM) to track faces from video sequences; and then, FAPs are extracted from every frame of the video based on an extended model of Wincandidate 3.1. Facial appearance details are transformed from each frame by mapping an expression ratio image to the original image. We adopt wavelet to synthesize expressive details by combining the low-frequency signals of the original face and high-frequency signals of the expressive face from each frame of the video. Experimental results show that our proposed algorithm is suitable for reproducing realistic, expressive facial animations.

关键词： image based rendering facial animation texture transform.

Multi secret image color visual cryptography schemes for general access structures

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Progress in Natural science:Materials International 2006年第4期16卷 431-436页

作者： YI Feng, WANG Daoshun , LUO Ping, HUANG Liansheng and DAI Yiqi department of computer {2. and technology, Tsinghua university, Beijing 100084, china [a]department of computer {2. and technology Tsinghua University Beijing China

In the proposed visual cryptography schemes for general access structures, the single secret image black-and-white visual cryptography schemes with meaningful shares have been constructed, in which the shares are innocent looking images. The meaningful shares have not been realized in single secret image color schemes; neither have the multi secret images color schemes. In this paper, the multi secret images color visual cryptography schemes for general access structures with meaningful shares are constructed by the method of matrix concatenation, the pixel expansion is obtained, and the validity of the scheme is proven. In our scheme, the different combination of meaningful color shares can be used to recover distinct color secret images. The multi secret images black-and-white visual cryptography scheme is a special case of our color scheme.

关键词： visual cryptography secret sharing scheme general access structure.

Generalized Group Signature Scheme

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Wuhan university Journal of Natural sciences 2001年第Z1期6卷 500-504页

作者： Li Zi chen 1, Wu Xu dong 2. Dai Yi qi 1 1 department of computer {2. and technology, Tsinghua university, Beijing 100084, china 2.department of computer {2.,Jiaozuo university, Jiaozuo 454003, china department of computer {2. and technology Tsinghua University Beijing China department of computer {2. Jiaozuo University Jiaozuo China

The concept of generalized group signature scheme will be present. Based on the generalized secret sharing scheme proposed by Lin and Harn, a non interactive approach is designed for realizing such generalized group signature scheme. Using the new scheme, the authorized subsets of the group in which the group member can cooperate to produce the valid signature for any message can be randomly specified.

关键词： digital signature group signature secret sharing

维普期刊数据库

A new family of windows——convolution windows and their applications

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science china(Technological sciences) 2005年第4期48卷 468-480页

作者： ZHANG Jieqiu1,2. LIANG Changhong1 & CHEN Yanpu3 1. department of Applied Math. & Phys., College of science, Airforce Engineering {2., Xi’an 710051, china 2. National Key Laboratory of Antennas and Microwave technology, Xidian {2., Xi’an 710071, china 3. computer Center, Xi’an Communication College, Xi’an 710106, china 1. department of Applied Math. & Phys. College of Science Airforce Engineering University 710051 Xi’an China 2. National Key Laboratory of Antennas and Microwave technology Xidian University 710071 Xi’an China 3. computer Center Xi’an Communication College 710106 Xi’an China

A new family of windows is constructed by convolutions via a few rectangular windows with same time width and is thus referred to as convolution windows. The expressions of the second-order up to the eighth-order convolution windows in both the time and frequency domains are derived. Their applications in high accuracy harmonic analysis of periodic signals are investigated. Comparisons between the proposed windows and some known windows with the same width shows that, when the synchronous deviation of data sampling is slight, the proposed ones have the least effect of spectral leakage. Therefore, the new windows are well suited for high accuracy harmonic analysis and parameter estimation for periodic signals. The error analysis and computer simulations show that the estimation errors, corresponding to frequency, amplitude and phase of every harmonic component of a signal, are proportional to the pth power of the relative frequency deviation in case of the pth-order convolution window is applied to windowing signal of approximately p cycles. By introducing real time adjustment in sampling interval, the proposed algorithm can adaptively trace signal frequency and lead to less sampling synchronous deviation. The proposed approach has the advantages of easy implementation and high measure precision and can be used in harmonic analysis of quasi-periodic signals whose fundamental frequency drifts slowly with time.

关键词： signal processing harmonic analysis window function convolution window synchronous error spoctral leakage

维普期刊数据库

STUDIES ON RETRIEVAL OF THE TURBULIVITY OF ATMOSPHERIC BOUNDARY LAYER

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Journal of Hydrodynamics 2006年第2期18卷 177-183页

作者： WANG Ting-fang HUANG Si-xun XIANG Jie Institute of Meteorology PLA University of Science and Technology Nanjing 211101 China Center of Meteorology Chengdu Air Force Chengdu 610041China Key Laboratory of Meso-Scale Severe Weather/MOE Depariment of Atmospheric Sciences Nanjing UniversityNanjing 210093 China

The variational adjoint method was applied to retrieving the turbulivity of the atmospheric Ekman boundary layer along with the regularization principle, The validity of the method was verified by using the idealized data, and then the turbulivity profile and the geostrophic wind profile were retrieved through it for real observational wind filed data.

关键词： atmospheric boundary layer turbulivity,Tikhonov regularization principle parameter retrieval

维普期刊数据库

Spatial continuity incorporated multi-attribute fuzzy clustering algorithm for blood vessels segmentation

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science china(Information sciences) 2010年第4期53卷 752-759页

作者： HAO JuTao1*, ZHAO JingJing2.& LI MingLu3 1School of Optical-Electrical and computer Engineering, university of Shanghai for {2. and technology, Shanghai 2.0093, china 2.5} of Electrical Engineering, Shanghai university of Electric Power, Shanghai 2.0090, china 3department of computer {2. and Engineering, Shanghai Jiaotong university, Shanghai 2.02.0, china 1. School of Optical-Electrical and computer Engineering University of Shanghai for Science and Technology Shanghai 200093 China2. Department of Electrical Engineering Shanghai University of Electric Power Shanghai 200090 China3. Department of Computer Science and Engineering Shanghai Jiaotong University Shanghai 200240 China

A three-dimensional representation of vasculature can be extremely important in image-guided neurosurgery, pre-surgical planning. In this paper, a spatial continuity incorporated multi-attribute fuzzy clustering algorithm (MAFCM S) is proposed to segment entire blood vessels from TOF MRA images. This clustering method takes both the intensity information and the geometrical information into account, while most of the cur- rent clustering methods only deal with the former. In this method, a new dissimilarity measure, which integrates the intensity and the geometry shape dissimilarity, is introduced. Because of the presence of the geometrical information, the new measure is able to differentiate the pixels with similar intensity values within different geometrical shape structures. Experimental results show that the new algorithm can get better segmentation.

关键词： fuzzy c-means clustering scale space analysis spatial continuity blood vessel segmentation multi-attribute fuzzy clustering

A Novel Missense Mutation(L2.6Q)in Cholesteryl Ester Transfer Protein Gene Related to Coronary Heart Disease

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Acta Biochimica et Biophysica Sinica 2004年第1期36卷 33-36页

作者： Ke-Qin ZHENG, Si-Zhong ZHANG, Li ZHANG, De-Jia HUANG, Lin-Chuan LIAO, and Yi-Ping HOU ( department of Medical Genetics, West china Hospital Division of Human Morbid Genomics, Key Laboratory ofBiotherapy of Human Diseases of Ministry of Education, Sichuan {2., chengdu 610041, china department of Cardiology, West china Hospital, Sichuan {2., chengdu 610041, china School of Basic and Forensic Medicine, Sichuan {2., chengdu 610041, china) department of Medical Genetics West China Hospita Division of Human Morbid Genomics Key Laboratory of Biotherapy of Human Diseases of Ministry of Education Sichuan University Chengdu 610041 Chin

Cholesteryl ester transfer protein (CETP) is a key participant in the reverse transport of cholesterol from the peripheral tissues to the liver. To understand the role that CETP gene plays in the pathogenesis of coronary heart disease (CHD) , the promoter region, all 16 exons and adjacent intronic regions of CETP gene were screened for single nucleotide polymorphisms (SNPs) in 2.3 CHD patients and 2.9 controls by a combination of PCR, denaturing high performance liquid chromatography (DHPLC), molecular cloning, and DNA sequencing. A novel missense mutation in the CETP gene was identified. This mutation (L2.6Q) was a T-to-A conversion at codon 2.6 of exon 10 which replaced the codon for leucine (CTG) with the codon for glutamine (CAG). Association study revealed that L2.6Q mutation was associated with CHD with a significantly higher mutant allele frequency in the CHD patients than that in the controls (0. 160 vs. 0.091,x2. 9.014, P = 0.003), and that the odds ratio for the development of CHD was 1.83 for

关键词： cholesteryl ester transfer protein gene (CETP gene) coronary heart disease (CHD) missense mutation plasma lipids single nucleoti.de polymorphism (SNP)

Entropy number and non-linear approximations on multivariate Besov space by manifolds of finite pseudo-dimension

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Progress in Natural science:Materials International 2006年第3期16卷 260-265页

作者： LONG Jingfan and FANG Gensun (School of Mathematical sciences, Beijing Normal university, Beijing 100875, {2. department of computer science, Information technology Institute, Beijing 100101, {2.) [a]School of Mathematical sciences Beijing Normal University Beijing China [b]department of computer {2. Information Technology Institute Beijing China

We determine the asymptotic order of entropy number and optimal non -linear approximations of anisotropic periodic Besov class of Bpθr(Td') (1≤p≤∞,1≤0≤∞) by manifolds of finite pseudo-dimension in the metric Lq... 详细信息

关键词： Pseudo-dimension anisotropic Besov class of functions entropy number nonlinear width.

Fuzzy dynamic characteristic modeling and adaptive control of nonlinear systems and its application to hypersonic vehicles

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science china(Information sciences) 2011年第3期54卷 460-468页

作者： LI HongBo , SUN ZengQi, MIN HaiBo & DENG JianQiu department of computer {2. and technology, Tsinghua university, Beijing 100084, china 1. department of computer {2. and technology Tsinghua University Beijing 100084 China

In this paper, a fuzzy dynamic characteristic modeling and adaptive control method is proposed for a class of nonlinear systems. By employing fuzzy dynamic characteristic model, the controlled plant is described as a slowly time-varying fuzzy system, wherein the parameters are estimated online by using recursive Least-Squares algorithm. Under this framework, a fuzzy adaptive controller is constructed, and the stability condition of the closed-loop system is also derived. The main advantage of the proposed method lies in no requirement for the prior knowledge of system model and less parameters to tune, which allows engineers to operate it in a simple, straightforward manner. The proposed method is applied to the control of hypersonic vehicle, and simulation results are given to demonstrate the effectiveness of the obtained results.

关键词： fuzzy control dynamic characteristic model adaptive control hypersonic vehicle