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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 agricultural {3. {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

Building a next generation Internet with source address validation architecture

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Science in China(Series F) 2008年第11期51卷 1681-1691页

作者： WU JianPing1,3.REN Gang1,3.& LI Xing2,3.1 department of Computer Science,Tsinghua university,beijing 10008{3.China 2 department of {{3. engineering,Tsinghua university,beijing 10008{3.China 3.Tsinghua National Laboratory for information Science and Technology(TNList) ,beijing 10008{3.China department of Computer Science Tsinghua University Beijing 100084 China department of electronic engineering Tsinghua University Beijing 100084 China Tsinghua National Laboratory for information Science and Technology (TNList) Beijing 100084 China

The IP packet forwarding of current Internet is mainly destination based. In the forwarding process, the source IP address is not checked in most *** causes serious security, management and accounting problems. Based on the drastically increased IPv6 address space, a ＂source address validation architecture＂（SAVA） is proposed in this paper, which can guarantee that every packet received and forwarded holds an authenticated source IP address. The design goals of the architecture are lightweight, loose coupling, ＂multi-fence support＂ and incremental deployment. This paper discusses the design and implementation for the architecture, including inter-AS, intra-AS and local subnet. The performance and scalability of SAVA are described. This architecture is deployed into the CNGI-CERNET2 infrastructure a large-scale native IPv6 backbone network of the China Next Generation Internet project. We believe that the SAVA will help the transition to a new, more secure and dependable Internet.

关键词： IP source address validation network architecture network security

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 & electronic {3., Hang/hou {4. of Commerce, Hangzhou 3.003., China 2. department, of electronic {3., Hangzhou institute of electronics {3., Hangzhou 3.003., China 3. State Key Laboratory on Machine Perception, Peking {4., beijing 100871, China Correspondence should be addressed to Yu Mei department of information & electronic {3. Hangzhou University of Commerce Hangzhou China State Key Laboratory on Machine Perception Peking University Beijing China department of electronic engineering 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).

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 university of Chemical Technology,beijing,100029,China 2 National Institute of Metrology,100013.beijing,China 3.department of Electrical and electronic engineering,Tottori university,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 3. 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

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, beijing Polytechnic {3., Ph.D, CIE senior member ({4. of electronic engineering, beijing Polytechnic {3., beijing 100022) 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

Preparation of nanocrystalline BaTiO_3.ceramics

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Science China(Technological Sciences) 2009年第6期52卷 1730-1734页

作者： DENG XiangYun1,2,LI DeJun1,LI JianBao2,WANG XiaoHui3.& LI LongTu3.1 college of Physics and electronic information,Tianjin Normal {3.,Tianjin 3.03.7,China 2 Materials and Chemical {4. Institute,Key Laboratory for Hainan Advantage Resources and Applied Technology in Chemical {4. Material of Ministry of Education,Hainan Provincial Key Laboratory of Research on Utilization of Si-Zr-Ti,Hainan {3.,Haikou 570228,China 3.department of Materials Science and {4.,Tsinghua {3.,beijing 100084.China college of Physics and electronic information Tianjin Normal University Tianjin 300387 China Materials and Chemical engineering Institute Key Laboratory for Hainan Advantage Resources and Applied Technology in Chemical Engineering Material of Ministry of Education Hainan Provincial Key Laboratory of Research on Utilization of Si-Zr-Ti Hainan University Haikou 570228 China department of Materials Science and engineering Tsinghua University Beijing 100084 China

The high-dense nanocrystalline BaTiO3.BT)ceramics with grain size smaller than 100nm have been successfully prepared by the two step sintering and the spark plasma sintering(SPS)*** successive transitions in nanograin BT ceramics from rhombohedral to orthorhombic,tetragonal and cubic transitions,similar to those in coarse BT ceramics,were revealed by in-situ temperature dependent Raman *** multiphase coexistence and the diffused phase transition character were demonstrated in the 8nm nanocrystalline BT ceramics.

关键词： nanocrystalline BaTiO3 ceramics preparation microstructure size effect

Influence of Yb^(3.) concentration on the upconversion luminescence of oxyfluoride material doped with Er^(3.)

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Science China(Physics,Mechanics & Astronomy) 2010年第2期53卷 310-314页

作者： ZHAO SuLing1,XU Zheng1,WANG LiHui2 & S. Wageh3.1 Institute of Optoelectronic Technology,Key Laboratory of Luminescence and Optical information (beijing Jiaotong {3.),Ministry of Education,beijing 10004.,China 2 department of Physics,Chinese People’s Public Security {3.,beijing 10003.,China 3.Physics & engineering Mathematics department Faculty of electronic engineering Menufiya {3.,Menouf 3.952,Egypt 1. Institute of Optoelectronic Technology Key Laboratory of Luminescence and Optical Information (Beijing Jiaotong University) Ministry of Education Beijing 100044 China2. Department of Physics Chinese People’s Public Security University Beijing 100038 China3. Physics & Engineering Mathematics Department Faculty of Electronic Engineering Menufiya University Menouf 32952 Egypt

In this paper,a new upconversion luminescent material co-doped with Erbium and Ytterbium is reported. The upconversion luminescence transition routes and related properties are studied. The results show that the absorption and emission intensities under excitation of 980 nm laser increase with the increase of the Yb3. concentration. The red emission is stronger than the green emission. The energy transfer process plays an important role in the upconversion mechanism.

关键词： upconversion luminescence Er3. Yb3.

The normal numbers of the fuzzy systems and their classes

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Science China(information Sciences) 2010年第11期53卷 2215-2229页

作者： LI HongXing1,3. YUAN XueHai1, WANG JiaYin2 & LI YuCheng3.1Faculty of electronic information and Electrical engineering, Dalian {3. of Technology, Dalian 116024. China 2School of Mathematical Sciences, {4. Normal {3., {4. 100875, China 3.8} of Automation, North China {3. of Technology, {4. 10014., China 1. Faculty of electronic information and Electrical engineering Dalian University of Technology Dalian 116024 China3. Department of Automation North China University of Technology Beijing 100144 China2. School of Mathematical Sciences Beijing Normal University Beijing 100875 China

R-fuzzy set is defined in this paper, which is regarded as the generalization of the Zadeh fuzzy set. By means of CRI method, some fuzzy systems are constructed by suitably using several kinds of R-fuzzy sets as fuzzy inference antecedents, such as interpolation fuzzy system, Bernstein fuzzy system, Lagrange fuzzy system and Hermite fuzzy system. A notion of the normal number of the fuzzy system is defined here, we have shown that all fuzzy systems are able to be classified as three classes such as the normal fuzzy systems, the regular fuzzy systems and the singular fuzzy systems under the significance of the normal numbers of fuzzy systems. Finally, the generalized Bernstein polynomial is obtained by constructing Bernstein fuzzy system, it is proved that the generalized Bernstein polynomial is uniformly convergent in C[a,b] under a weaker condition, and it is pointed out that there exist generalized Bernstein polynomials to be not convergent in C[a,b] by use of constructing a counterexample.

关键词： R-fuzzy set fuzzy system the normal number of fuzzy system universal approximation property for fuzzy system

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 information & Control {3., {4. university of Technology, {4. 100124. China 2 department of electronic information {3., Hong Kong Polytechnic university, Hong Kong, China 1. department of electronic information & Control {3. 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.264 stereoscopic video coding disparity estimation motion estimation