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On the use of simplex methods in constructing quadratic models

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Science china Mathematics 2007年第7期50卷 913-924页

作者： Qing-hua ZHOU 1 College of Mathematics and Computer,Hebei university,Baoding 071002,china 2 State Key laboratory of Scientific and Engineering computing,Institute of Computational Mathematics and Scientific/Engineering computing,Academy of Mathematics and Systems Science,Chinese Academy of Sciences,beijing 100080,china College of Mathematics Computer Hebei University Baoding 071002 China State Key laboratory of Scientific Engineering computing Institute of Computational Mathematics Scientific/Engineering computing Academy of Mathematics Systems Science Chinese Academy of Sciences Beijing 100080 China

In this paper, we investigate the quadratic approximation methods. After studying the basic idea of simplex methods, we construct several new search directions by combining the local information progressively obtained during the iterates of the algorithm to form new subspaces. And the quadratic model is solved in the new subspaces. The motivation is to use the information disclosed by the former steps to construct more promising directions. For most tested problems, the number of functions evaluations have been reduced obviously through our algorithms.

关键词： unconstrained optimization trust region method quadratic model Lagrange function simplex methods direct methods 90C56

CONVERGENCE OF (0,1,2,3) INTERPOLATION ON AN ARBITRARY SYSTEM OF NODES

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Journal of Computational Mathematics 2001年第2期19卷 151-156页

作者： Ying-guang Shi (Institute of Computation, Hunan Normal university, Changsha 410081, china) (Institute of Computational Mathematics and Scientific/Engineering computing, Academy of Mathematics and Systems Sciences, Chinese Academy of Sciences, beijing 100 湖南师范大学湖南长沙 410081

Provides information on a study which simplified and improved convergence of (0,1,2,3) interpolation on an arbitrary system of nodes. Definitions and notations; Results; Conjectures.

关键词： Hermite interpolation Hermite-Fejer interpolation convergence

Emotional Gait Generation for a Humanoid Robot

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International Journal of Automation and computing 2010年第1期7卷 64-69页

作者： Lun Xie Zhi-Liang Wang Wei Wang Guo-Chen Yu School of Information Engineering, university of Science and technology beijing, beijing 100083, PRC School of Information Engineering University of Science and Technology Beijing Beijing PRC

In this paper, an emotional mathematical model and affective state probability description space of a humanoid robot are set up on the basis of psycho-dynamics＇ psychological energy and affective energy conservation law. The emotional state transferring process and hidden Markov chain algorithm of stimulating transition process are then studied. The simulation results show that the mathematical model is applicable to the authentic affective state change rule of human beings. Finally, the gait generation experiment results of control signal and electric current tracking wave-form are presented to demonstrate the validity of the proposed mathematical model.

关键词： Emotional mathematical model humanoid robot hidden Markov chain stimulating transition process gait generation.

Tree wavelet approximations with applications

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Science china Mathematics 2005年第5期48卷 680-702页

作者： XU Yuesheng & ZOU Qingsong Department of Mathematics, Syracuse university, Syracuse, NY 13244, USA Institute of Mathematics, Academy of Mathematics and System Sciences, Chinese Academy of Sciences, beijing 100080, china Department of Scientific computing and Computer Science, Zhongshan university, Guangzhou 510275, china 1. Department of Mathematics Syracuse University 13244 Syracuse NY USA 2. Institute of Mathematics Academy of Mathematics and System Sciences Chinese Academy of Sciences 100080 Beijing China 3. Department of Scientific computing and Computer Science Zhongshan University 510275 Guangzhou China

We construct a tree wavelet approximation by using a constructive greedy scheme (CGS). We define a function class which contains the functions whose piecewise polynomial approximations generated by the CGS have a prescribed global convergence rate and establish embedding properties of this class. We provide sufficient conditions on a tree index set and on bi-orthogonal wavelet bases which ensure optimal order of convergence for the wavelet approximations encoded on the tree index set using the bi-orthogonal wavelet bases. We then show that if we use the tree index set associated with the partition generated by the CGS to encode a wavelet approximation, it gives optimal order of convergence.

关键词： greedy algorithms tree wavelet approximations Besov spaces.

Capability of evolutionary cryptosystems against differential cryptanalysis

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Science china(Information Sciences) 2011年第10期54卷 1991-2000页

作者： ZHANG HuanGuo 1,2 ,LI ChunLei 1,2 & TANG Ming 1,2 1 School of Computer,Wuhan university,Wuhan 430072,china 2 Key laboratory of Aerospace Information Security and trusted computing of Ministry of Education,Wuhan university,Wuhan 430072,china 1. School of Computer Wuhan University Wuhan 430072 China2. Key Laboratory of Aerospace Information Security and Trusted Computing of Ministry of Education Wuhan University Wuhan 430072 China

The evolutionary cryptosystem is a new *** paper studies its security level resisting against differential *** is shown that the evolutionary cryptosystem possesses higher resistance than its initial fixed cryptosystem against differential *** the basis of the relationship among the data complexity,the bit advantage and the success rate of differential cryptanalysis,it is proven that more data is needed for attacking the evolutionary cryptosystem when the bit advantage and success rate are ***,it is shown that the time complexity for attacking the evolutionary cryptosystem is higher than that of differential attacking its initial fixed cryptosystem with the same amount of plaintext-ciphertext *** research indicates that the evolutionary cryptosystem is more robust than its initial fixed cryptosystem against differential cryptanalysis.

关键词： information security cryptology evolutionary cryptosystem cryptanalysis differential cryptanalysis

Parallel algorithm for real-time contouring from grid DEM on modern GPUs

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Science china(Technological Sciences) 2010年第S1期53卷 33-37页

作者： CHEN Zhuo,SHEN Lei,ZHAO YanQing & YANG ChongJun State Key laboratory of Remote Sensing Science,Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and beijing Normal university,beijing 100101,china 1. State Key laboratory of Remote Sensing Science Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University Beijing 100101 China

A real-time algorithm for constructing contour maps from grid DEM data is *** runs completely within the programmable 3D visualization *** interpolation is paralleled by rasterizer units in the graphics card,and contour line extraction is paralleled by pixel *** each frame of the rendering,we first make an elevation gradient map out of original terrain vertex data,then figure out the final contour lines with image-space processing,and directly blend the results on the original scene to obtain a final scene with contour map using *** implement this method in our global 3D-digitalearth system with Direct3D?9.0c API and tested on some consumer level PC *** arbitrary scene with certain LOD level,the process takes less than 10 ms,giving topologically correct,anti-aliased contour lines.

关键词： contour map contour lines paralleled computing 3D terrain GPU digital earth

Identification Algorithm Based on the Approximate Least Absolute Deviation Criteria

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International Journal of Automation and computing 2012年第5期9卷 501-505页

作者： Bao-Chang Xu Xin-Le Liu Department of Automation, china university of Petroleum, beijing 102249, china 1. Department of Automation China University of Petroleum Beijing 102249 China

Considering the situation that the least-squares (LS) method for system identification has poor robustness and the least absolute deviation (LAD) algorithm is hard to construct, an approximate least absolute deviation (ALAD) algorithm is proposed in this paper. The objective function of ALAD is constructed by introducing a deterministic function to approximate the absolute value function. Based on the function, the recursive equations for parameter identification are derived using Gauss-Newton iterative algorithm without any simplification. This algorithm has advantages of simple calculation and easy implementation, and it has second order convergence speed. Compared with the LS method, the new algorithm has better robustness when disorder and peak noises exist in the measured data. Simulation results show the efficiency of the proposed method.

关键词： System identification least absolute deviation (LAD) Gauss-Newton algorithm robustness disorder and peak noise

Accountable authority key policy attribute-based encryption

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Science china(Information Sciences) 2012年第7期55卷 1631-1638页

作者： WANG YongTao 1,2 ,CHEN KeFei 1,3 ,LONG Yu 1,4 & LIU ZhaoHui 2 1 Department of Computer Science and Engineering,Shanghai Jiao Tong university,Shanghai 200240,china 2 china Information technology Security Evaluation Center,beijing 100085,china 3 Shanghai Key laboratory of Scalable computing and Systems,Shanghai Jiao Tong university,Shanghai,200240,china 4 State Key laboratory of Information Security,Graduate School of Chinese Academy of Sciences,100039,china 1. Department of Computer Science and Engineering Shanghai Jiao Tong University Shanghai 200240 China2. China Information Technology Security Evaluation Center Beijing 100085 China3. Shanghai Key Laboratory of Scalable Computing and Systems Shanghai Jiao Tong University Shanghai 200240 China4. State Key Laboratory of Information Security Graduate School of Chinese Academy of Sciences Beijing 100039 China

We present an accountable authority key policy attribute-based encryption (A-KPABE) *** this paper,we extend Goyal's work to key policy attribute-based encryption *** first generalize the notion of accountable authority in key policy attribute-based encryption scenario,and then give a *** addition,our scheme is shown to be secure in the standard model under the modified Bilinear Decisional Diffie-Hellman (mBDDH) assumption.

关键词： accountable authority key policy attribute-based encryption standard model access structure

The structural analysis of fuzzy measures

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Science china(Information Sciences) 2011年第1期54卷 38-50页

作者： ZHANG Ling1,ZHANG Bo2 & ZHANG YanPing1 1 Computer Science College,Anhui university,Hefei 230039,china 2State Key Lab of Intelligent technology & Systems Tsinghua National Lab for Information Science & technology Information Science & technology College,Computer Science & technology,Tsinghua university,beijing 100084,china 1. Computer Science College Anhui University Hefei 230039 China2. State Key Lab of Intelligent Technology & Systems Tsinghua National Lab for Information Science & technology Information Science & technology College Computer Science & Technology Tsinghua University Beijing 100084 China

From quotient space based granular computing theory we explore the fuzzy measures of fuzzy sets. Based on the structural analysis of fuzzy sets,we present an"isotropism"*** this assumption we achieved the following insights:(1)the uniqueness of a fuzzy measure being isotropic on a finite complete semi-ordered set;(2)the necessary and suffcient condition of the isomorphism for fuzzy measure functions in fuzzy mathematics;(3)the necessary and suffcient condition that fuzzy measures have fuzzy and granular monotonicity;(4)under a certain assumption,the analytic expression for fuzzy *** results clarify the relationship between fuzzy measures and granular computing,reveal the essence of fuzzy measures,and provide a simple way of constructing fuzzy measures.

关键词： quotient space fuzzy set fuzzy measure rough set structural analysis