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Efficient video cutout based on adaptive multilevel banded method

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science china(Information sciences) 2012年第5期55卷 1082-1092页

作者： CHEN MinGang 1,SUI BoCong 1,GAO Yan 2.& MA LiZhuang 1 1 department of computer {2. and engineering,shanghai Jiao Tong University,shanghai 2.02.0,china 2.Software engineering Institute,east china Normal University,shanghai 2.0062.china 1. department of computer {2. and engineering Shanghai Jiao Tong University Shanghai 200240 China2. Software Engineering Institute East China Normal University Shanghai 200062 China

Although many efficient image cutout approaches have been proposed,it is still a challenge to cut out foreground objects from a video clip because of the costs of time and memory consumption and the difficulty in maintaining temporal coherence for the cutout *** this paper,we propose a novel and efficient video cutout approach by extending a multilevel banded image segmentation method to video *** our method,the segmentation results are propagated frame by frame at the lowest resolution level based on optical flow,and are refined in image pyramids level by level through banded graph *** construct an adaptive narrow band to ensure that the segmentation result falls exactly into the narrow band during *** results show that the video cutout approach based on adaptive multilevel bands dramatically reduces time and memory costs,and achieves ideal segmentation results.

关键词： video object cutout multilevel band graph cuts video segmentation

Chemical Extraction Preparation of Delithiated Cathode Materials of Li-ion Battery

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Journal of Wuhan University of technology(Materials science) 2009年第6期24卷 863-866页

作者：闫时建 School of Materials science and engineering Taiyuan University of Science and Technology

A method of conventional chemical reaction to prepare delithiated cathode materials of Li-ion battery was introduced. The cathode material of Li-ion battery was mixed with oxidizing agent Na2.2.8 in water solution, and the solution was stirred continuously to make the chemical reaction proceed sufficiently, then the reaction product was filtered and finally the insoluble delithiated cathode material was obtained. A series of tests were conducted to verify the composition, crystal structure and electrochemical property of the delithiated cathode materials were all desirable. This method overcomes the shortcomings of battery charging preparation and chemical extraction preparation employing other oxidizing agents.

关键词： chemical extraction delithiated cathode material Li-ion battery

Relations Between Characteristic Function,Positive P-Representation and Coherent Thermal State

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Communications in Theoretical Physics 2007年第7期48卷 67-70页

作者： FAN Hong-Yi XU Xing-Lei department of Material science and {2.,University of science and technology of china,Hefei 2.002.,china2.department of Physics,shanghai Jiao Tong University,shanghai 2.0030,china3 department of Physics,Heze University,Heze 2.4015,china department of Material science and {2. University of Science and Technology of China department of Physics Shanghai Jiao Tong University department of Physics Heze University

We employ the coherent thermal states(a kind of entangled states)in thermal field dynamics to establisha complete entangled state formalism expressing pseudo-classical representations of density operator for light ***,the relationship between the coherent thermal state and the characteristic function and the positive Prepresentation in quantum optics theory are obtained.

关键词： coherent thermal state characteristic function positive P-representation

Preparation of PFSA/PSf hollow fiber composite membranes with recovered PFSA for the pervaporation separation of EtOH/H_2.

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science china Chemistry 2010年第1期53卷 273-280页

作者： LANG WanZhong1,2.TONG Wei2.XU ZhenLiang2.& GUO YaJun1 1department of Chemistry,shanghai Normal University,shanghai 2.02.4,china 2.hemical engineering Research Center,east china University of science and technology,shanghai 2.02.7,china 1. department of Chemistry Shanghai Normal University Shanghai 200234 China2. Chemical Engineering Research Center East China University of Science and Technology Shanghai 200237 China

Perfluorosulfonic acid/Polysulfone(PFSA/PSf) hollow fiber composite membranes have been prepared by dip-coating method using PSf ultrafiltration(UF) membrane as substrate with recovered *** composite membranes were applied to the pervaporation separation of 95% ethanol(EtOH)/H2. *** images show that the thickness of the PFSA skin layer of the composite membranes is about 2.μm,much thinner than those of other PFSA composite membranes revealed in the *** of annealing temperature,coating solution concentration and counter-ions of PFSA on the pervaporation performances of the composite membranes were *** total flux decreases and separation factor increases with the increase of annealing *** highest permeation flux of 32.0 g m-2.h-1 and a separation factor of 5.4 is obtained for the composite membrane annealed at 80°*** lowest permeation flux of 396 g m-2.h-1 and a separation factor of 2..7 is obtained for the composite membrane annealed at 160°*** permeation performances of the PFSA/PSf composite membrane are evidently influenced by the counter-ions of *** flux sequence of the PFSA/PSf composite membranes with different counter-ions is H+>Li+>Ca2.>Mg2.>Na+>K+>Ba2.>Fe3+>Al3+,and the separation factor sequence is H+3+2.2.2.3+.The apparent activation energy △Eapp values of the composite membranes with different counter-ions were calculated by Arrhenius *** sequence of △Eapp values for the membranes with monovalent counter-ions is Li+>Na+>K+.There are very little variations of △Eapp values between the composite membranes with three divalent counterions(Mg2.,Ca2. and Ba2.),and the △Eapp values of the composite membranes with two trivalent counterions(Fe3+ and Al3+) are relatively high.

关键词： pervaporation hollow fiber composite membrane perfluorslulfonic acid(PFSA) ethanol(EtOH)/H2. mixture

l-SkyDiv query:Effectively improve the usefulness of skylines

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science china(Information sciences) 2010年第9期53卷 1785-1799页

作者： HUANG ZhenHua1,2.,XIANG Yang1 & LIN ZiYu3 1department of computer {2. and technology,Tongji University,shanghai 2.1804,china 2.he Key Laboratory of Embedded System and Service Computing,Ministry of Education,Tongji University,shanghai 2.0092.china 3department of computer {2. and technology,Peking University,Beijing 100871,china 1. department of computer {2. and technology Tongji University Shanghai 201804 China2. The Key Laboratory of Embedded System and Service Computing Ministry of Education Tongji University Shanghai 200092 China3. Department of Computer Science and Technology Peking University Beijing 100871 China

Skyline query processing has recently received a lot of attention in database *** a set of multi-dimensional objects,the skyline query finds the objects that are not dominated by *** the best of our knowledge,the existing researches mainly focus on how to efficiently return the whole skyline ***,as the cardinality and dimensionality of input dataset increase,the number of skylines grows exponentially,and hence this "huge" skyline set is completely useless to *** by the above fact,in this paper,we present a novel type of l-SkyDiv query,which only returns l skylines having maximum diversity,to improve the usefulness of skyline ***,we prove that the l-SkyDiv query belongs to the NP-Hard problem theoretically,and propose three efficient heuristic algorithms whose time complexities are polynomial to fast implement the proposed ***,we present detailed theoretical analyses and extensive experiments,demonstrating that our algorithms are both efficient and effective.

关键词： skyline query diversity heuristic algorithm query optimization performance evaluation

A whisker-like carbon composite for the immobilization of laccase and its bioelectrochemistry

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science china Chemistry 2010年第6期53卷 1332-1336页

作者： MA GuoXian1,2.ZHONG QingDong2.& LU TianHong3 1department of Chemical engineering,{2. Institute of technology,{2. 2.02.3,china 2.chool of Materials science and engineering,{2. University,{2. 2.0072.china 3department of Chemistry,Nanjing Normal University,Nanjing 2.0097,china 1. department of Chemical engineering Shanghai Institute of Technology Shanghai 200233 China2. School of Materials Science and Engineering Shanghai University Shanghai 200072 China3. Department of Chemistry Nanjing Normal University Nanjing 210097 China

A novel mesoporous carbon/whisker-like carbon (MCWC) composite was used for the immobilization of laccase (Lac) and its bioelectrochemical behaviors were *** was confirmed by XPS that Lac was strongly adsorbed on the surface of the MCWC *** cyclic voltammetric results showed that the immobilized Lac underwent a direct quasi-reversible electrochemical *** value of the electron transfer rate constant ks was estimated to be 0.770 s-1,indicating a reasonably fast electron transfer between the immobilized Lac and the underlying *** surface concentration (I-) of Lac was estimated to be 2.730 × 10-12.mol/*** experimental results showed that the immobilized Lac displayed an appreciable electrocatalytic activity to the electrochemical reduction of *** properties could be attributed to the particular structure of loosely packed nanometer-scale carbon whiskers and the existence of a large amount of oxygen-containing *** immo- bilization method and the novel carrier (MCWC) may find new applications in fabricating the biocatalysts for biofuel cells.

关键词： laccase whisker-like carbon composite direct electrochemical reaction oxygen bioelectrochemistry

Superconductivity of small metal grains

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science china(Physics,Mechanics & Astronomy) 2005年第4期48卷 431-441页

作者： ZHENG Renrong1 CHEN Zhiqian2.& ZHU Shunquan1,3 1. department of Physics, shanghai Normal University, shanghai 2.02.4, china 2. department of Physics, Southwest Normal University, Chongqing 400715, china 3. department of computer and Electric technology, shanghai Business School, shanghai 2.1400, china 1. department of Physics Shanghai Normal University 200234 Shanghai China 2. department of Physics Southwest Normal University 400715 Chongqing China 3. department of computer and Electric {2. Shanghai Business School 201400 Shanghai China

The formulas of the energy gap and superconducting critical temperature appropriate for systems with both odd and even number of electrons are derived; the bases of the derivations are BCS theory and energy level statistics. Numerical results qualitatively agree with the experimental phenomena. i.e., the superconductivity of small metallic grains will first enhance then decrease to zero when the grain are getting smaller and smaller. The calculations indicate that the above phenomena happen in the metallic grains belonging to Gaussian Orthogonal Ensemble (GOE) and Gaussian Unitary ensemble (GUE) with zero spin; The superconductivity of small metallic grains in Gaussian Symplectic Ensemble (GSE) will monotonically decrease to zero with the decreasing of the grain size. The analyses suggest that the superconductivity enhancements come from pairing and the balance of the strengths between spin-orbital coupling and external magnetic field. In order to take the latter into account, it is necessary to include the level statistics given by Random Matrix Theory (RMT) in describing small metallic grains.

关键词： size effect, superconductivity enhancements, small metallic grains.

Complete quantum circuit of Haar wavelet based MRA

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Chinese science Bulletin 2005年第16期50卷 1796-1798页

作者： HE Yuguo1,2.& SUN Jigui1,3 1. College of computer science and {2., Jilin University, Changchun 130012. china 2. department of computer science and engineering, Beijing Institute of {2., Beijing 100081, china 3. Key Laboratory of Computation and Knowledge engineering of Min-istry of Education, Jilin University, Changchun 130012. china College of computer science and {2. Jilin University Changchun 130012 China

Wavelet analysis has applications in many ar- eas, such as signal analysis and image processing. We pro- pose a method for generating the complete circuit of Haar wavelet based MRA by factoring butterfly matrices and con- ditional perfect shuffle permutation matrices. The factoriza- tion of butterfly matrices is the essential part of the design. As a result, it is the key point to obtain the circuits of I 2. ⊕ W ⊕ I 2. ? 2. ?2. In this paper, we use a simple means to de- velop quantum circuits for this kind of matrices. Similarly, the conditional permutation matrix is implemented entirely, combined with the scheme of Fijany and Williams. The cir- cuits and the ideas adopted in the design are simple and in- telligible.

关键词：量子计算量子算法量子电路 Haar微波 MRA

Performance Modeling and Approximate Analysis of Multiserver Multiqueue Systems with Poisson and Self-similar Arrivals

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Journal of University of science and technology Beijing 2001年第2期8卷 145-151页

作者： Zhiguang Shan, Chuang Lin, Yang Yang, Yan Wang (Information engineering School, University of science and {2. Beijing, Beijing 100083, china) (department of computer science and {2., Tsinghua University, Beijing 100084, china) Univ Sci & Technol Beijing Informat Engn Sch Beijing 100083 Peoples R China Tsinghua Univ Dept Comp Sci & Technol Beijing 100084 Peoples R China

The problem of state space explosion is still ran outstanding challenge in Markovian performance analysis for multiserver multiqueue (MSMQ) systems. The system behavior of a MSMQ system is described using stochastic high-level Petri net (SHLPN) models, and an approximate performance analysis technique is proposed based on decomposition and refinement methods as well as iteration technique. A real MSMQ system, Web-server cluster, is investigated. The performance of an integrated scheme of request dispatching and scheduling is analyzed with both Poisson and self-similar request arrivals. The study shows that the approximate analysis technique significantly reduces the complexity of the model solution and is also efficient for accuracy of numerical results.

关键词： multiserver multiqueue (MSMQ) system Web-server cluster performance analysis stochastic high-level Petri net (SHLPN) request dispatching request scheduling