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A general communication performance evaluation model based on routing path decomposition

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Journal of zhejiang University-Science C(Computers and Electronics) 2011年第7期12卷 561-573页

作者： Ai-lian CHENG 1,Yun PAN 1,2,Xiao-lang YAN 2,Ruo-hong HUAN 3 (1 Department of information Science and Electronic engineering,zhejiang University,hangzhou 310027,china) (2 Institute of VLSI Design,zhejiang University,hangzhou 310027,china) (3 college of Computer Science and Technology,zhejiang University of Technology,hangzhou 310023,china) Department of information Science and Electronic engineering Zhejiang University Institute of VLSI Design Zhejiang University

The network-on-chip (NoC) architecture is a main factor affecting the system performance of complicated multi-processor systems-on-chips (MPSoCs).To evaluate the effects of the NoC architectures on communication efficiency,several kinds of techniques have been developed,including various simulators and analytical *** simulators are accurate but time consuming,especially in large space explorations of diverse network configurations;in contrast,the analytical models are fast and flexible,providing alternative methods for performance *** this paper,we propose a general analytical model to esti-mate the communication performance for arbitrary NoCs with wormhole routing and virtual channel flow *** resolve the inherent dependency of successive links occupied by one packet in wormhole routing,we propose the routing path decomposition approach to generating a series of ordered link *** we use the traditional queuing system to derive the fine-grained transmission latency for each network *** to our experiments,the proposed analytical model provides a good approximation of the average packet latency to the simulation results,and estimates the network throughput precisely under various NoC configurations and ***,the analytical model runs about 10 5 times faster than the cycle-accurate NoC *** applications of the model including bottleneck detection and virtual channel allocation are also presented.

关键词： Analytical model Communication performance Network-on-chip (NoC) Queuing system Routing path decom-position Virtual channel

User-controllable mesh segmentation using shape harmonic signature

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Progress in Natural Science:Materials International 2009年第4期19卷 471-478页

作者： Yongwei Miao a,b, Jieqing Fenga, Jinrong Wanga,c, Xiaogang Jin a a State Key Laboratory of CAD & CG, zhejiang University, hangzhou 310027, china b college of Science, zhejiang University of Technology, hangzhou 310032, china c information Science & engineering school, hangzhou Normal University, hangzhou 310036, china [a]State Key Laboratory of CAD & CG Zhejiang University Hangzhou 310027 China [b]College of Science Zhejiang University of Technology Hangzhou 310032 China [c]Information Science & Engineering School Hangzhou Normal University Hangzhou 310036 China

Due to different shape modeling applications, partitioning a given complex 3D mesh model into some patches or meaningful subparts is one of the fundamental problems in digital geometry processing. By using the high-dimensional mean-shift clustering scheme in shape signature space, a new method is proposed which can generate user-specified segmentation results automatically for different applications. The shape signature is composed of mesh geometric attributes and its spectral harmonics. The latter one can reflect mesh frequency spectrum information. The low frequency components are essential for semantics-oriented segmentation, while the high frequency components are important for purely geometry-oriented segmentation. The effects of the proposed method are demonstrated by several examples.

关键词： Mesh segmentation Manifold harmonic analysis Shape harmonic signature Mean-shift clustering

Repetitive learning control of nonlinear systems over finite intervals

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Science china(information Sciences) 2010年第1期53卷 115-128页

作者： SUN MingXuan1, WANG DanWei2 & CHEN PengNian3 1college of information engineering, zhejiang University of Technology, hangzhou 310014, china 2school of Electrical and Electronic engineering, Nanyang Technological University, Singapore 639794 3Department of Mathematics, china Institute of Metrology, hangzhou 310018, china 1. college of information engineering Zhejiang University of Technology Hangzhou 310014 China2. School of Electrical and Electronic Engineering Nanyang Technological University Singapore 639794 Singapore3. Department of Mathematics China Institute of Metrology Hangzhou 310018 China

Iterative learning control requires initial repositioning, while the time functions to be learned should be of periodicity in repetitive control. However, there are cases in practice where the time-varying unknowns are not periodic but repetitive, and repetitive learning control is applicable with avoidance of initial repositioning. In this paper, repetitive learning control designs are presented for a broader class of nonlinear systems over finite intervals. The Freeman formula is modified and used for stabilization of the nominal nonlinear time-varying system undertaken. The global stability of the learning system and asymptotic convergence of the tracking error are established through analysis of both partially and fully saturated learning algorithms, respectively. The repetitive learning control method is theoretically shown to be effective in dealing with time-varying parametric uncertainties.

关键词： Initial condition problem convergence iterative learning control repetitive control repetitive learning control nonlinear systems

An output delay approach to fault estimation for sampled-data systems

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Science china(information Sciences) 2012年第9期55卷 2128-2138页

作者： WEN ChengLin 1,QIU AiBing 2 & JIANG Bin 3 1 Institute of information and Control,hangzhou Dianzi University,hangzhou 310018,china 2.school of Electrical engineering,Nantong University,Nantong 226019,china 3 college of Automation engineering,Nanjing University of Aeronautics and Astronautics,Nanjing 210016,china 1. Institute of information and Control Hangzhou Dianzi University Hangzhou 310018 China2. School of Electrical Engineering Nantong University Nantong 226019 China3. College of Automation Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

The problem of fault estimation for a class of non-uniformly sampled-data systems is investigated from the time delay point of view in this ***,the output delay approach is employed to model the sampled-data system as a continuous-time one with time-varying delay ***,based on the analysis of the inapplicability of the adaptive fault diagnosis observer in such class of time-delay systems,a novel augmented fault estimation observer design method is proposed to guarantee the exponential convergence of the estimation ***,an extension to the case of time varying fault estimation for the noisy sampled-data systems is ***,simulation results of a flight control system are presented to demonstrate the effectiveness of the proposed method.

关键词： fault estimation non-uniformly sampled-data augmented observer output delay

Research on Fuzzy information Retrieval

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Journal of Systems Science and Systems engineering 2001年第2期13卷 185-190页

作者： YAO Min 1, HUANG Yan-jun 21.college of information, zhejiang University, hangzhou 310028, china2.school of Economics, zhejiang University, hangzhou 310028, china college of information Zhejiang University Hangzhou 310028 China school of Economics Zhejiang University Hangzhou 310028 China

The information retrieval is one of the common operations in computer information systems. This paper proposes a kind of information retrieval method based on fuzzy set theory.

关键词： fuzzy sets fuzzy techniques information retrieval

Formal Verification under Unknown Constraints

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Wuhan University Journal of Natural Sciences 2005年第1期10卷 43-46页

作者： LI Guang-hui 1,2,3 , LI Xiao-wei 2,31. school of information engineering, zhejiang Forestry college, hangzhou 311300, zhejiang, china 2. Institute of Computing Technology, Chinese Academy of Sciences, Beijing 100080, china 3. Graduate school of the Chinese Academy of Sciences, Beijing 100039, china school of information engineering Zhejiang Forestry College Hangzhou 311300 Zhejiang China

We present a formal method of verifying designs with unknown constraints (e.g., black boxes) using Boolean satisfiability (SAT). This method is based on a new encoding scheme of unknown constraints, and solves the corresponding conjunctive normal form (CNF) ***,this method can avoid the potential memory explosion, which the binary decision diagram (BDD) based techniques maybe suffer from, thus it has the capacity of verifying large designs. Experimental results demonstrate the efficiency and feasibility of the proposed method.

关键词： formal verification unknown constraints black box Boolean satisfiability Boolean comparison

Performance of iteratively decoded bit-interleaved coded modulation with chaos based interleaving strategies

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Science china(information Sciences) 2010年第4期53卷 833-841页

作者： ZOU XueLan1*, LIU WeiYan2 & FENG GuangZeng3 1Department of Electronic and information engineering, zhejiang Institute of Media and Communications, hangzhou 310018, china 2Department of information engineering, Jiangsu City Vocation college, Nanjing 210036, china 3college of Communication and information engineering, Nanjing University of Posts and Telecommunications, Nanjing 210003, china 1. Department of Electronic and information engineering Zhejiang Institute of Media and Communications Hangzhou 310018 China2. Department of Information Engineering Jiangsu City Vocation College Nanjing 210036 China3. College of Communication and Information Engineering Nanjing University of Posts and Telecommunications Nanjing 210003 China

Bit-interleaved coded modulation with iterative decoding (BICM-ID) is a bandwidth efficient trans- mission scheme which is well suitable for next-generation mobile communications. The interleaver design is critical to the high performance of BICM-ID. In this paper we investigate the application of the chaos theory to the interleaver design to further improve the performance of BICM-ID. A new interleaving scheme based on the chaos theory is proposed. Compared with the random interleaver, the proposed approach has the ad- vantages including lower system delay and higher transmission efficiency. Simulation results in both additive white Gaussian noise (AWGN) channel and Rayleigh fading channel are provided, which demonstrates that the new interleaver is better than the random interleaver and exhibits excellent performance when applied to the BICM-ID system.

关键词： chaos interleaving bit-interleaved coded modulation (BICM) iterative decoding

An oblivious fragile watermarking scheme for images utilizing edge transitions in BTC bitmaps

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Science china(information Sciences) 2012年第11期55卷 2570-2581页

作者： ZHANG Yong1,LU ZheMing2 & ZHAO DongNing1 1ATR National Defense Technology Key Laboratory,college of information engineering,Shenzhen University,Shenzhen 518060,china 2school of Aeronautics and Astronautics,zhejiang University,hangzhou 310027,china 1. ATR National Defense Technology Key Laboratory College of Information Engineering Shenzhen University Shenzhen 518060 China2. School of Aeronautics and Astronautics Zhejiang University Hangzhou 310027 China

As one of the famous block-based image coding schemes,block truncation coding(BTC) has been also applied in digital *** BTC-based watermarking or hiding schemes usually embed secret data by modifying the BTC encoding stage or BTC-compressed data,obtaining the watermarked image with poorer quality than the BTC-compressed *** paper presents a new oblivious image watermarking scheme by exploiting BTC *** the traditional schemes,our approach does not really perform the BTC compression on images during the embedding process but utilizes the parity of the number of horizontal edge transitions in each BTC bitmap to guide the watermark embedding and extraction *** embedding process starts by partitioning the original cover image into non-overlapping 4×4 blocks and performing BTC on each block to obtain its BTC *** watermark bit is embedded in each block by modifying at most three pixel values in the block to make sure that the parity of the number of horizontal edge transitions in the bitmap of the modified block is equal to the embedded watermark *** the extraction stage,the suspicious image is first partitioned into non-overlapping 4×4 blocks and BTC is performed on each block to obtain its ***,by checking the parity of the number of horizontal edge transitions in the bitmap,we can extract one watermark bit in each *** results demonstrate that the proposed watermarking scheme is fragile to various image processing operations while keeping the transparency very well.

关键词： fragile image watermarking oblivious watermarking block truncation coding data hiding image authentication

Bloch constant of holomorphic mappings on the unit polydisk of C^n

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Science china Mathematics 2008年第4期51卷 652-659页

作者： WANG JianFei~(1+) LIU TaiShun~2 1 college of Mathematics and Physics information engineering zhejiang Normal University Jinhua 321004,china 2 Department of Mathematics Huzhou teachers college Huzhou 313000 china college of Mathematics and Physics Information Engineering Zhejiang Normal University Jinhua China Department of Mathematics Huzhou Teachers College Huzhou China

In this paper,we give a definition of Bloch mappings defined in the unit polydisk D^n, which generalizes the concept of Bloch functions defined in the unit disk *** is known that Bloch theorem fails unless we have some restrictive assumption on holomorphic mappings in several complex *** shall establish the corresponding distortion theorems for subfamiliesβ(K)andβ_(loc)(K) of Bloch mappings defined in the polydisk D^n,which extend the distortion theorems of Liu and Minda to higher *** an application,we obtain lower and upper bounds of Bloch constants for various subfamilies of Bloeh mappings defined in D^*** particular,our results reduce to the classical results of Ahlfors and Landau when n=1.

关键词： Bloch constant Bloch mapping univalent ball critical point Julia lemma locally biholomorphic mapping Landau constant