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A relative local variational principle for topological pressure

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science china Mathematics 2010年第6期53卷 1491-1506页

作者： MA XianFeng1,CHEN ErCai2,3,& ZHANG AiHua2,4 1Department of Mathematics,East china university of science and technology,Shanghai 200237,china 2.chool of Mathematics and computer science,nanjing normal university,nanjing 210097,china 3Center of Nonlinear science,nanjing university,nanjing 210093,china 4College of Mathematics and Physics,nanjing university of Posts and Telecommunications,nanjing 2.0046,china Department of Mathematics East China University of Science and Technology School of Mathematics and computer science Nanjing Normal University Center of Nonlinear science Nanjing University College of Mathematics and Physics Nanjing University of P

We define the relative local topological pressure for any given factor map and open cover,and prove the relative local variational principle of this *** precisely,for a given factor map π:(X,T)→(Y,S) between two topological dynamical systems,an open cover U of X,a continuous,real-valued function f on X and an S-invariant measure ν on Y,we show that the corresponding relative local pressure P(T,f,U,y) satisfies sup μ∈M(X,T){ hμ(T,U|Y)+∫X f(x)dμ(x) :πμ=ν}=∫Y P(T,f,U,y)dν(y),where M(X,T) denotes the family of all T-invariant measures on ***,the supremum can be attained by a T-invariant measure.

关键词： pressure conditional entropy relative local variational principle

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An unconstrained optimization method using nonmonotone second order Goldstein's line search

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science china Mathematics 2007年第10期50卷 1389-1400页

作者： Wen-yu SUN~(1+) Qun-yan ZHOU~(1,2) ~1 School of Mathematics and computer science,nanjing normal university,nanjing 210097,china ~2 Department of Basic Courses,Jiangsu Teachers university of technology,Changzhou 213001,china School of Mathematics and computer science Nanjing Normal University Nanjing China Department of Basic Courses Jiangsu Teachers University of Technology Changzhou China

In this paper, an unconstrained optimization method using the nonmonotone second order Goldstein's line search is proposed. By using the negative curvature information from the Hessian,the sequence generated is shown to converge to a stationary point with the second order optimality conditions. Numerical tests on a set of standard test problems confirm the efficiency of our new method.

关键词： nonmonotone method, direction of negative curvature, line search, descent pair,unconstrained optimization

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Communication network designing:Transmission capacity,cost and scalability

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science china(Information sciences) 2012年第11期55卷 2454-2465页

作者： ZHANG GuoQiang1,2,3 & ZHANG GuoQing1 1Institute of Computing technology,Chinese Academy of sciences,Beijing 100190,china 2.chool of computer science and technology,nanjing normal university,nanjing 2.0046,china 3Provincial Key Laboratory for computer Information Processing technology,Soochow university,Suzhou 215000,china Institute of Computing technology Chinese Academy of Sciences Beijing China School of computer science and technology Nanjing Normal University Nanjing China Provincial Key Laboratory for computer Information Processing technology Soochow University Suzhou China

Despite the growing number of works centering around the traffic dynamics on complex networks,these researches still have some common shortcomings,e.g.,too simple traffic flow model and lack of considerations for the designing cost and scalability *** paper builds on a more realistic traffic flow model,and offers a holistic view on the network designing *** addition to the extensively studied transmission capacity,this paper takes designing cost and scalability as two other designing objectives,and presents a quantitative study of how different designing choices independently and collectively influence these objectives by the introduction of a cartesian coordinate *** is shown that different kinds of network topologies display different shapes of achievable solution spaces and exhibit different abilities to achieve cost-effective and scalable *** particular,we find the philosophy underlying empirical network designing and engineering today fails to meet the cost-effective and scalable designing requirements,and propose a cost-effective and scalable designing scheme for BA-like networks,i.e.,the efficient routing combined with effective betweenness based link bandwidth *** addition,when designing a thoroughly new network from the beginning,we find that ER network is a good candidate to achieve cost-effective and scalable designing in most settings.

关键词： cost-effective communication network designing network transmission efficiency network topology traffic dynamics next generation network scalable network designing

ASYMPTOTIC normalITY OF MAXIMUM QUASI-LIKELIHOOD ESTIMATORS IN GENERALIZED LINEAR MODELS WITH FIXED DESIGN

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Journal of Systems science & Complexity 2008年第3期21卷 463-473页

作者： Qibing GAO Yaohua WU Chunhua ZHU Zhanfeng WANG School of Mathematics and computer science Nanjing Normal University Nanjing 210097 China Department of Statistics and Finance University of Science and Technology of China Hefei 230026 China School of Mathematics science Anhui University Hefei 230039 China

In generalized linear models with fixed design, under the assumption λ↑_n→∞ and other regularity conditions, the asymptotic normality of maximum quasi-likelihood estimator ^↑βn, which is the root of the quasi-likelihood equation with natural link function ∑i=1^n Xi（yi -μ（Xi′β）） = 0, is obtained, where λ↑_n denotes the minimum eigenvalue of ∑i=1^nXiXi′, Xi are bounded p × q regressors, and yi are q × 1 responses.

关键词： Asymptotic normality fixed design generalized linear models maximum quasi-likelihood estimator

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P2P traffic optimization

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science china(Information sciences) 2012年第7期55卷 1475-1492页

作者： ZHANG GuoQiang 1,2 ,TANG MingDong 3 ,CHENG SuQi 2,4 ,ZHANG GuoQing 2 ,SONG HaiBin 5 ,CAO JiGuang 6 & YANG Jing 7 1 School of computer science and technology,nanjing normal university,nanjing 2.0046,china 2 Institute of Computing technology,Chinese Academy of sciences,Beijing 100190,china 3 School of computer science and Engineering,Hunan university of science and technology,Xiangtan 411201,china 4 Graduate university of Chinese Academy of sciences,Beijing 100190,china 5 nanjing R&D Center,Huawei Technologies,nanjing 210012,china 6 china Academy of Telecommunication Research of MIIT,Beijing 100191,china 7 china Mobile Research Institute,Beijing 100053,china School of computer science and technology Nanjing Normal University Nanjing China Institute of Computing technology Chinese Academy of Sciences Beijing China School of computer science and Engineering Hunan University of Science and Technology Xiangtan China Graduate university of Chinese Academy of sciences Beijing China nanjing R&D Center Huawei Technologies Nanjing China china Academy of Telecommunication Research of MIIT Beijing China china Mobile Research Institute Beijing China

Peer-to-peer (P2P) based content distribution systems have emerged as the main form for content distribution on the Internet,which can greatly reduce the distribution cost of content providers and improve the overall system ***,the mismatch between the overlay and underlay networks causes large volume of redundant traffic,which intensifies the tension between P2P content providers and ***,how to efficiently use network resources to reduce the traffic burden on the ISPs is crucial for the sustainable development of P2P *** paper surveys the state-of-art P2P traffic optimization technologies from three perspectives:P2P cache,locality-awareness and data *** details,comparison between these technologies and their applicabilities are presented,followed by a discussion of the issues that remain to be addressed and the direction of future content distribution research.

关键词： P2P traffic localization P2P traffic optimization P2P cache locality-awareness network coding content-centric network

Contourlet HMT model with directional feature

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science china(Information sciences) 2012年第7期55卷 1563-1578页

作者： WANG XiangHai 1,2,3 ,CHEN MingYing 1 ,SONG ChuanMing 1,2 ,XU MengChun 1 & FANG LingLing 3 1 College of computer and Information technology,Liaoning normal university,Dalian 116029,china 2 State Key Laboratory for Novel Software technology,nanjing university,nanjing 210093,china 3 Provincial Key Laboratory for computer Information Processing technology,Soochow university,Suzhou 215006,china College of computer and Information technology Liaoning Normal University Dalian China State Key Laboratory for Novel Software technology Nanjing University Nanjing China Provincial Key Laboratory for computer Information Processing technology Soochow University Suzhou China

According to Shanno's information theory,the directional feature of texture is defined as the value of directional variable when an image signal attains a singularity of random *** terms of this definition,we calculate the texture's directional features using Tamura's method and study the directional probability distribution of Contourlet *** we find that the directional features tend to be conveyed across parent and child *** on this conclusion,we establish a novel probability distribution model of hidden direction variables under the condition of hidden state variable's distribution,named Contourlet HMT model with directional *** structure and training method of the model are presented as ***,an unsupervised context-based image segmentation algorithm is proposed on the basis of the proposed *** effectiveness is verified via extensive experiments carried out on several synthesized images and remote sensing images.

关键词： directional feature Contourlet HMT Contourlet HMT with directional feature unsupervised texture segmentation

A secure multi-party computation solution to intersection problems of sets and rectangles

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Progress in Natural science:Materials International 2006年第5期16卷 538-545页

作者： LI Shundong, DAI Yiqi, WANG Daoshun and LUO Ping (Department of computer science and technology, Beijing normal university, Beijing 100875, china Department of computer science and technology, Tsinghua university, Beijing 100084, china) Department of computer science and technology Beijing Normal University Beijing 100875 China 2. Department of computer science and technology Tsinghua University Beijing 100084 China

Secure multi-party computation (SMC) is a research focus in international cryptographic community. At present, there is no SMC solution to the intersection problem of sets. In this paper, we first propose a SMC solution to this problem. Applying Cantor encoding method to computational geometry problems, and based on the solution to set-intersection problem, we further propose solutions to points inclusion problem and intersection problem of rectangles and further prove their privacy-preserving property with widely accepted simulation paradigm. Compared with the known solutions, these new solutions are of less computational complexity and less communication complexity, and have obvious superiority in computational and communication complexity.

关键词： Cantor encoding secure multi-party computation set-intersection rectangle-intersection computational complexity.

(2,n)secret sharing scheme for gray and color images based on Boolean operation

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science china(Information sciences) 2012年第5期55卷 1151-1161页

作者： DONG Lin 1,WANG DaoShun 1,LI ShunDong 2 & DAI YiQi 1 1 Department of computer science and technology,Tsinghua university,Beijing 100084,china 2 School of computer science,Shaanxi normal university,Xi'an 710062,china Department of computer science and technology Tsinghua University School of computer science Shaanxi Normal University

Traditional secret sharing (SS) schemes can reconstruct the secret precisely,but have high com-putation *** secret sharing (VSS) schemes use human visual system to reconstruct the secret without cryptographic computation,but have pixel expansion and loss of *** et *** a (2,n)-SS scheme for binary images based on Boolean operation,which has low computation complexity,no pixel expansion and the contrast is 1/*** this paper,we first construct an r runs (2,n)-SS scheme to improve the contrast of Wang et al.'s binary (2,n)-SS *** we present two approaches to construct r runs (2,n)-SS schemes for grayscale image and color *** two approaches are both based on Boolean operation,while one approach uses halftone technology and the other uses bit level *** proposed schemes have low computation complexity and almost ideal contrast.

关键词： secret sharing scheme Boolean operation halftone contrast

Seamlet carving for shape-aware image resizing

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science china(Information sciences) 2012年第5期55卷 1073-1081页

作者： LIN Xiao 1,2,SHENG Bin 1,MA LiZhuang 1,SHEN Yang 1 & CHEN ZhiHua 3 1 Department of computer science and Engineering,Shanghai Jiao Tong university,Shanghai 200240,china 2 Academy of Information technology,Luoyang normal university,Luoyang 471022,china 3 Department of computer science and Engineering,East china university of science and technology,Shanghai 200237,china Department of computer science and Engineering Shanghai Jiao Tong University Academy of Information technology Luoyang Normal University

In this paper we propose an optimized seam-carving approach for anti-shearing image *** image/video seam-carving strategy only focuses on deleting the pixels along 8-connected seams,which may lead to the obvious information loss during *** the traditional seam-carving methods,our approach can construct a seamlet to handle the discontinuous pixels and further achieve an optimized image resizing results with *** particular,to suppress zigzag artifacts,we introduce the anti-shearing energy into the seamlet generation,which includes two steps:1) the energy map is formalized by using Gabor filtering and the saliency map;2) The energy computation is optimized in Gabor feature space to obtain the resizing results without the connectivity *** experimental results and comparisons show the effectiveness of our method.

关键词： image resizing seamlet carving saliency map