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Networked Kalman filtering with combined constraints of bandwidth and random delay

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science china(Information sciences) 2012年第10期55卷 2343-2357页

作者： GE QuanBo 1,2,WEN ChengLin 1 & XU TingLiang 1 1 School of Automation,hangzhou Dianzi university,hangzhou 310018,china 2 State Key Laboratory of Industrial Control technology,zhejiang university,hangzhou 310027,china 1. School of Automation Hangzhou Dianzi University Hangzhou 310018 China2. State Key Laboratory of Industrial Control Technology Zhejiang University Hangzhou 310027 China

Kalman filter is a powerful tool in target tracking and self-localization across wireless sensor networks with many *** paper considers the filters design for networked systems with combined constraints of bandwidth and random delay,and proposes a kind of universal networked Kalman estimator for given linear time invariant(LTI) or determinate parameters(DP) systems,which are also called linear and determinate parameters(LDP) systems ***,two modeling ways to treat bit quantization error vector are given and the corresponding LDP systems taken after bit quantization are ***,we introduce an equivalent weighted summation form of the conventional linear Kalman filter,which fully uses two essential characteristics,namely offline computation property from the LDP systems and linear weighted summation property from the linear minimum mean square error ***,by adopting the replacement and innovation compensation operations,a kind of integrated networked estimator,involving two estimation algorithms with different modeling ways to bit quantization error actually,is presented based on the weighted summation filter for random delay *** proposed universal networked estimation algorithms have some outstanding advantages such as extensive application,concise algorithm structure,high estimate accuracy,and good running *** examples are demonstrated to validate the proposed networked estimation algorithms.

关键词： Kalman filter LDP systems LMMSE limited bandwidth random delay

P systems based multi-objective optimization algorithm

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Progress in Natural science:Materials International 2007年第4期17卷 458-465页

作者： Huang Liang, He Xiongxiong, Wang Ning and Xie Yi ( National Laboratory of Industrial Control technology, Institute of Advanced Process Control, zhejiang university, hangzhou 310027, china zhejiang university of technology, hangzhou 310033, china) [a]National Laboratory of Industrial Control technology Institute of Advanced Process Control Zhejiang University Hangzhou China [b]zhejiang university of technology Hangzhou China

Based on P systems, this paper proposes a new multi-objective optimization algorithm (PMOA). Similar to P systems, PMOA has a cell-like structure. The structure is dynamic and its membranes merge and divide at different stages. The key rule of a membrane is the communication rule which is derived from P systems. Mutation rules are important for the algorithm, which has different ranges of mutation in different membranes. The cooperation of the two rules contributes to the diversity of the population, the conquest of the muhimodality of objective function and the convergence of algorithm. Moreover, the unique structure divides the whole population into several sub populations, which decreases the computational complexity. Almost a dozen popular algorithms are compared using several test problems. Simulation results illustrate that the PMOA has the best performance. Its solutions are closer to the true Pareto-optimal front

关键词： P systems evolutionary algorithm multi-objective optimization Pareto optimality.

Preparation of TiC/Ni_3Al Composites by Upward Melt Infiltration

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Journal of Materials science & technology 2000年第4期16卷 387-392页

作者： Yi PAN (Department of Materials science and Engineering, zhejiang university, hangzhou 310027, china) Kewei SUN (National Engineering Research Center of Solid Waste Resources Recovery, Kunming university of science and technology,Kunming 650093, china) Department of Materials science and Engineering Zhejiang University Hangzhou 310027 China National Engineering Research Center of Solid Waste Resources Recovery Kunming University of Science and Technology Kunming 650093 China

TiC/Ni_3Al composites have been prepared using upward infiltration method. The densification was performed by both Ni_3Al melt filling and TiC sintering during the infiltration. The dissolution of TiC in liquid Ni_3Al has been evidenced by finding Ni_3(Al,Ti)C after fast cooling in the TiC/Ni_3Al composites. The dissolution may be responsible for the infiltration and sintering. Compared with downward infiltration, the upward infiltration brought about higher strength and fracture toughness and shorter infiltration time. TiC/20 vol. pct Ni_3Al composite processed by upward infiltration had a flexural strength of 1476 MPa with a statistic Weibull modulus of 20.2 and a fracture toughness of 20.4 MPa . Better mechanical properties may be attributed to melt unidirectional movement in upward infiltration.

关键词： TiC Preparation of TiC/Ni3Al Composites by Upward Melt Infiltration Ni Al

MECHANISM OF DEUTERIUM CRACKING IN PALLADIUM

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Acta Metallurgica Sinica(English Letters) 1993年第2期6卷 136-139页

作者： SUN Dalin LEI Yongquan CHEN Yanglin WU Jing WANG Qidong zhejiang university,hangzhou,china Department of Materials science and Engineering,zhejiang university,hangzhou 310027,china zhejiang Univ Hangzhou China

After 290 h electrochemical charging of deuterium,the density of dislocation in well-annealed Pd was increased from 10~8/cm^2 to over 10~12/cm^2 and a large amount of bubble-like voids or cracks was observed by optical and transmission electron *** mechanism of deuterium cracking is believed due to the formation of molecular De during the segregstion and combination of deuterium atoms around *** results showed that the lattice constant of Pd increased from 0.3890 nm to 0.4034 nm.

关键词： deuterium cracking Pd

Weighted weak type estimates for commutators of the Marcinkiewicz integrals

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science china Mathematics 2004年第1期47卷 83-95页

作者： DING Yong, LU Shanzhen & ZHANG PuDepartment of Mathematics, Beijing Normal university, Beijing 100875, china Department of Information and Computing science, zhejiang Institute of science and technology, hangzhou 310033, china 1. Department of Mathematics Beijing Normal University 100875 Beijing China 2. Department of Information and Computing science Zhejiang Institute of Science and Technology 310033 Hangzhou China

In this paper the authors give the weighted weak LlogL type estimates for a class of the higher order commutator generated by the Marcinkiewicz integral and a BMO function. In addition, the weak type norm inequalities... 详细信息

关键词： Marcinkiewicz integral, commutator, Ap weight, weak type estimate.

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

Enhanced activity of yqhD oxidoreductase in synthesis of 1,3-propanediol by error-prone PCR

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Progress in Natural science:Materials International 2008年第12期18卷 1519-1524页

作者： Hongmei Li~a Jia Chen~a Yinghua Li~b a Institute of Food science and Biological technology,university of Shanghai for science and technology,Shanghai 200093,china b Institute of Pharmaceutical Engineering,zhejiang university,hangzhou 310027,china [a]Institute of Food science and Biological technology University of Shanghai for Science and Technology Shanghai 200093 China [b]Institute of Pharmaceutical Engineering Zhejiang University Hangzhou 310027 China

yqhD oxidoreductase was determined to be an NADP-dependent dehydrogenase,and was more active toward 3-HPA when compared to 1,3-propanediol *** further improve enzyme activity towards 3-hydroxypropionaldehyde (3-HPA),error-prone PCR was implemented to mutant yqhD *** mutants,D99QN147H and Q202A with increased catalytic and affinity efficiency,were obtained after one round of error-prone polymerase chain *** the catalytic efficiency of the mutant D99QN147H was up to 4-fold greater than the wild enzyme (0.0375 min-1mM-1vs.0.0078 min-1mM-1).The recombined strain containing pEY28yqhD D99QN147H yielded 28 g L-1of 1,3-propanediol in the fed-batch LB cultures (1 L volume) with an initial 3-HPA concentration of 40 g L-1,which was higher than the 21 and 17 g L-1of 1,3-propanediol from the mutant Q202A and the wild-type,*** for propionaldehyde,the optimal mutant D99QN147H also exhibited higher activity on a range of substituted aldehydes than the wild- type.

关键词： yqhD oxidoreductase Error-prone PCR Catalytic efficiency 1,3-Propanediol

Strong near-epoch dependence

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science china Mathematics 2004年第4期47卷 497-507页

作者： LIN ZhengyanDepartment of Mathematics, zhejiang university, hangzhou 310028, china 1. Department of Mathematics Zhejiang University 310028 Hangzhou China

We introduce a new class of dependent sequences of random variables, which is a subclass of near-epoch dependent sequences, but can also be approximated by mixing sequences. For this kind of sequences of random variables, we call them strong nearepoch dependent sequences, a p-order, p ＞ 2, (maximum) moment inequality is established under weaker dependence sizes.

关键词： near-epoch dependence, mixingale, strong near-epoch dependence, moment inequality, convergence.

Analytical method for softness abrasive flow field based on discrete phase model

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science china(Technological sciences) 2010年第10期53卷 2867-2877页

作者： JI ShiMing1,2, XIAO FengQing1,2 & TAN DaPeng1,2 1Key Laboratory of Special Purpose Equipment and Advanced Manufacturing technology, (zhejiang university of technology), Ministry of Education, hangzhou 310014, china 2Key Laboratory of Special Purpose Equipment and Advanced Manufacturing technology of zhejiang Province, hangzhou 310014, china 1. Key Laboratory of Special Purpose Equipment and Advanced Manufacturing technology (Zhejiang University of Technology) Ministry of Education Hangzhou 310014 China2. Key Laboratory of Special Purpose Equipment and Advanced Manufacturing Technology of Zhejiang Province Hangzhou 310014 China

Aiming at the problem of difficult contact finishing for mini structural surface in course of mould manufacturing,a new no-tool precision machining method based on soft abrasive flow machining (SAFM) was proposed. It allocated restrained component near surface machined,constituted restrained abrasive flow passage,and made the surface become a segment of passage wall. It could control turbulence abrasive flow in restrained passage,realize micro cutting for passage wall,and utilize the irregular motion of abrasive flow to eliminate the mono-directional marks on machined surfaces,and the precision could reach the specular level. A two-phase dynamic model of abrasive flow oriented to SAFM combined with discrete phase model (DPM) was established,the law of two-phase flow motion and the related physical parameters was obtained by corresponding numerical simulation method,and the mechanism of precision machining in SAFM was discussed. Simulation results show that the abrasive flow machining process mainly appears as translation of ablating location with the influence by granular pressure,and as the variation of machining efficiency with the influence by near-wall particle velocity. Thus via control of the inlet velocity and its corresponding machining time,it is supposed to work out the machining process according to the machining requirements by using the Preston equation to seek the relationship among velocity,pressure and material removing rate. By tracking near-wall particles,it can be confirmed that the movement of near-wall abrasive particles is similar to stream-wise vortices. The cutting traces on workpiece surfaces assume disorderly arrangement,so the feasibility of the SAFM method can be reaffirmed.

关键词： structural flow passage ultra-precision machining softness abrasive flow discrete phase model