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Lp shape deformation

science China(Information sciences) 2012年第5期55卷 983-993页

作者： GAO Lin1,ZHANG GuoXin 1 & LAI YuKun 2.1 Department of computer science and Technology,Tsinghua {2.,Beijing 100084,China 2.school of computer science and Informatics,Cardiff {2.,Wales CF2. 3AA,UK 1. Department of computer science and Technology Tsinghua University Beijing 100084 China2. School of Computer Science and Informatics Cardiff University Wales CF24 3AA UK

Shape deformation is a fundamental tool in geometric *** methods consider preserving local details by minimizing some energy functional measuring local distortions in the L 2.*** strategy distributes distortions quite uniformly to all the vertices and penalizes ***,there is no unique answer for a natural deformation as it depends on the nature of the *** by recent sparse signal reconstruction work with non L 2.norm,we introduce general L p norms to shape deformation;the positive parameter p provides the user with a flexible control over the distribution of unavoidable *** with the traditional L 2.norm,using smaller p,distortions tend to be distributed to a sparse set of vertices,typically in feature regions,thus making most areas less distorted and structures better *** the other hand,using larger p tends to distribute distortions more evenly across the whole *** flexibility is often desirable as it mimics objects made up with different *** specifying varying p over the shape,more flexible control can be *** demonstrate the effectiveness of the proposed algorithm with various examples.

关键词： shape deformation Lp norm geometric modeling

Symbolic Computation Study of (2.1)-Dimensional Dispersive Long Wave Equations

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Communications in Theoretical Physics 2006年第8期46卷 199-202页

作者： LU Zhuo-Sheng~(1,2.+) and XIE Fu-Ding~(2.3) ~1school of science, Beijing {2. of Post and Telecommunications, Beijing 100876, China ~2.ey Laboratory of mathematics Mechanization, Academy of mathematics and System sciences, the Chinese Academy of sciences, Beijing 100080, China ~3Department of computer science, Liaoning Normal {2., Dalian 11602., China Department of Otolaryngology University Hospital VU P.O. Box 7057 1007 MB Amsterdam The Netherlands school of science Beijing University of Post and Telecommunications Beijing 100876 China

Seeking exact analytical solutions of nonlinear evolution equations is of fundamental importance in mathematical physics. In this paper, based on a constructive algorithm and symbolic computation, abundant new exact solutions of the (2.1)-dimensional dispersive long wave equations are obtained, among which there are soliton-like solutions, mult-soliton-like solutions and formal periodic solutions, etc. Certain special solutions are considered and some interesting localized structures are revealed.

关键词： dispersive long wave equations symbolic computation exact solution localized structure

Reverse extraction of early-age hydration kinetic equation from observed data of Portland cement

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science China(Technological sciences) 2010年第6期53卷 1540-1553页

作者： WANG Lin1,YANG Bo2.ZHAO XiuYang1,2.CHEN YueHui2.& CHANG Jun3 1 school of computer {2. and Technology,Shandong university,Jinan 2.0101,China 2.Provincial Key Laboratory for Network-based Intelligent Computing,university of Jinan,Jinan 2.002.,China 3 school of Material {2. and Engineering,university of Jinan,Jinan 2.002.,China 1. school of computer {2. and Technology Shandong University Jinan 250101 China2. Provincial Key Laboratory for Network-based Intelligent Computing University of Jinan Jinan 250022 China3. School of Material Science and Engineering University of Jinan Jinan 250022 China

The early-age hydration of Portland cement paste has an important impact on the formation of microstructure and development of ***,manual derivation of hydration kinetic equation is very difficult because there are multi-phased,multi-sized and interrelated complex chemical and physical reactions during cement *** this paper,early-age hydration kinetic equation is reversely extracted automatically from the observed time series of hydration degree of Portland cement using evolutionary computation method that combines gene expression programming and particle swarm optimization *** order to reduce the computing time,GPUs are used for acceleration in *** have shown that according to the extracted kinetic equation,simulation curve of early-age hydration is in good accordance with the observed experimental ***,this equation still has a good generalization ability even changing chemical composition,particle size and curing conditions.

关键词： Portland cement hydration kinetic equation reverse extraction gene expression programming particle swarm optimization

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Reliability-aware automatic composition approach for web services

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science China(Information sciences) 2012年第4期55卷 921-937页

作者： LI Mu 1,2.LI Bo 1,2.& HUAI JinPeng 1,2.1 State Key Laboratory of Software Development Environment,Beihang university,Beijing 100191,China 2.school of {2. science and Engineering,Beihang university,Beijing 100191,China 1. State Key Laboratory of Software Development Environment Beihang University Beijing 100191 China2. School of Computer Science and Engineering Beihang University Beijing 100191 China

In this paper,we study the reliability-aware synthesis problem for composing available services automatically and guaranteeing that the composed result satisfies the specification,such as temporal constraints of functionality and reliability,centered on a synthesis model for mediator of web services composition (CSM).This approach focuses on handling attributes and state relations,and permitting users and services to operate over them,i.e.,read /write their data values and compare them according to a dense state *** show that the reliability-aware synthesis problem for the specification is EXPTIME-complete and we give an exponential-time algorithm (CSM-NSA) which for a given formula ψ and a synthesis model,synthesizes available services in the library satisfying ψ over the synthesis model (if they exist) or responds with "not satisfiable" (otherwise).The specification ψ is a fragment of PCTL (probabilistic computation tree logic),obtained from "ordinary" CTL (computation tree logic) by replacing the EX,AX,EU and AU operation with their quantitative counterparts X >p,X =1,U >p,and U =1,*** opposed to NSA,we provide a more effective algorithm to replace the NSA algorithm called CSM-HSA (heuristic synthesis algorithm).Though HSA is an incomplete algorithm,the answer is *** experiments show that the HSA algorithm solves the problem of reliability-aware service synthesis effectively and efficiently.

关键词： reliability web services synthesis problem synthesis model heuristic algorithm

Sandwich Magnetoelectric Composites of Polyvinylidene Fluoride,Tb-Dy-Fe Alloy,and Lead Zireonate Titanate

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Journal of wuhan university of Technology(Materials {2.) 2007年第4期22卷 596-599页

作者：赵广辉熊传溪 State Key Laboratory of Advanced Technology for Materials Synthesis and Processing school of computer {2. and Technology Wuhan University of TechnologyWuhan 430070China school of Materials science and Engineering Wuhan University of TechnologyWuhan 430070China

The novel sandwich composites were prepared by sandwiching a polyvinylidene fluoride/Tb- Dy-Fe alloy composite （PVDF/Terfenol-D） between polyvinylidene fluoride/lead zirconate titanate composites （PVDF/PZT）. The maximum magnetoelectric effect voltage coefficient, （dE/dn）33max, of the sandwich composites is higher than that of three-phase composites at their own optimal loading level of Terfenol-D. This is attributed to less interface relaxations of strain and better polarization of the sandwich composites. When the volume fraction of Terfenol-D is higher than 0.10, no coupling interaction for three-phase composites could be observed, but （dE/dn）33max of sandwiched composites still reached 2. mV/（***）. At high magnetic field intensity, the magnetoelectric effect voltage coefficient, （dE/dn）33, of sandwich composites is higher than that of three-phase composites; at low magnetic field intensity, （dE/dn）33 of sandwich composites is lower than that of three-phase composites. At their resonance frequency, the （dE/dn）33max of the sandwich composites and the three phase composites are 150 mV/（***） and 42.mV/（cmoOe）, respectively. This significant increase of （dE/ dn）33max at resonance frequency confirms the improvement of maximum magnetoelectric effect coefficient via sandwich-structured composites.

关键词： magnetoelectric piezoelectric sandwiched composites

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Immigrant schemes for evolutionary algorithms in dynamic environments: Adapting the replacement rate

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science China(Information sciences) 2011年第7期54卷 1352-1364页

作者： YU Xin 1,TANG Ke 1 & YAO Xin 1,2.1 Nature Inspired Computation and Applications Laboratory,school of computer {2. and Technology,university of {2. and Technology of China,Hefei 2.002.,China 2.Centre of Excellence for Research in Computational Intelligence and Applications,school of computer {2.,university of Birmingham,Edgbaston,Birmingham B15 2.T,U.K. 1. Nature Inspired Computation and Applications Laboratory School of Computer Science and Technology University of Science and Technology of China Hefei 230027 China2. Centre of Excellence for Research in Computational Intelligence and Applications School of Computer Science University of Birmingham Edgbaston Birmingham B15 2TT UK

One approach for evolutionary algorithms (EAs) to address dynamic optimization problems (DOPs) is to maintain diversity of the population via introducing *** far all immigrant schemes developed for EAs have used fixed replacement *** paper examines the impact of the replacement rate on the performance of EAs with immigrant schemes in dynamic environments,and proposes a self-adaptive mechanism for EAs with immigrant schemes to address *** experimental study showed that the new approach could avoid the tedious work of fine-tuning the parameter and outperformed other immigrant schemes using a fixed replacement rate with traditionally suggested values in most cases.

关键词： evolutionary algorithm dynamic optimization problem immigrant scheme self-adaptive replace- ment rate

Design of robust output-feedback repetitive controller for class of linear systems with uncertainties

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science China(Information sciences) 2010年第5期53卷 1006-1015页

作者： WU Min 1 ? , ZHOU Lan 1 , SHE JinHua 2.& HE Yong 1 1 school of Information science and Engineering, Central South {2., Changsha 410083, China 2.school of computer science, Tokyo {2. of Technology, Tokyo 192.0982. Japan 1. school of Information science and Engineering Central South University Changsha 410083 China2. School of Computer Science Tokyo University of Technology Tokyo 192-0982 Japan

Repetitive control, which adds a human-like learning capability to a control system, is widely used in many fields. This paper deals with the problem of designing a robust repetitive-control system based on output feedback for a class of plants with time-varying structured uncertainties. A continuous-discrete two-dimensional hybrid model is established that accurately describes the features of repetitive control so as to enable independent adjustment of the control and learning actions. A sufficient condition for the robust stability of the repetitivecontrol system is given in terms of a linear matrix inequality. The condition is then used to obtain the parameters of the repetitive controller. Finally, a numerical example demonstrates the effectiveness of the method.

关键词： learning output feedback repetitive control robust control linear matrix inequality

Web Database Sampling Approach Based on Attribute Correlation

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wuhan university Journal of Natural {2.s 2010年第4期15卷 297-302页

作者： TIAN Jianwei, LI Shijun, TANG Xiaoyue school of computer, {2. university, {2. 430072. hubei, China school of computer Wuhan University Wuhan Hubei China

In this paper,we present a novel approach utilizing attributes correlation for the sampling task on nonuniform hidden databases. We propose the method of calculating the attributes dependency and construct the sampling template according to the attributes dependency. Then,we use the sampling template to gen-erate initial sampling queries and propose a bottom-up algorithm to search the sampling template. We also conduct extensive ex-periments over real deep Web sites and controlled databases to illustrate that our sampling method has good performance both on the quality and efficiency.

关键词： attributes correlation hidden database sampling template mutual information

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N-way blending problem of circular quadrics

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science China(Information sciences) 2010年第8期53卷 1546-1554页

作者： FANG MeiE 1,3 , Wang GuoZhao 2.& MA WeiYin 3 1 school of computer {2., Hangzhou Dianzi university, Hangzhou 310081, China 2.Department of mathematics, Zhejiang university, Hangzhou 310018, China 3 Department of MEEM, City university of Hong Kong, Hong Kong, China 1. school of computer {2. Hangzhou Dianzi University Hangzhou 310081 China3. Department of MEEM City University of Hong Kong Hong Kong China2. Department of Mathematics Zhejiang University Hangzhou 310018 China

A method of blending circular quadrics with parametric patches is proposed in this paper. It needs n rational bi-cubic B′ezier patches and two S-patches to blend n (n > 2. quadrics. Bi-cubic rational B′ezier patches are used to G 1 -continuously blend each pair of adjacent base surfaces. These patches enclose two n-sided holes. And an S-patch is used to fill each hole, which keeps nearly G 1-continuity. Explicit formulas of control points for both B′ezier patches and S-patches are derived from their constraint conditions, which make modeling by blending quadrics very simple and convenient. In addition, the shapes of the blending surfaces can be intuitively adjusted by free parameters.

关键词： circular quadrics blending n-way S-patch