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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 Science and technology,Tongji university,Shanghai 201804,china.2The Key Laboratory of Embedded System and Service Computing,Ministry of Education,Tongji university,Shanghai 200092,china.3Department of computer Science and technology,Peking university,beijing 100871,china Department of computer Science and technology Tongji University The Key Laboratory of Embedded System and Service Computing Ministry of Education Tongji University Department of computer Science and technology Peking University

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

In-situ Characterization of Non-aqueous Nano-dispersion Systems by Freeze-etching TEM and Comparative Study with Laser Scattering Method

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Journal of Wuhan university of technology(Materials Science) 2010年第3期25卷 432-436页

作者：欧忠文 Department of Architecture and Civil engineering Logistics Engineering University

In-situ characterization of non-aqueous nano-dispersion systems（NANDS） by freeze-etching transmission electron microscope（FETEM） was *** improve just-for-once successive rate of specimen preparation and get good characterization results,an improving specimen preparation method of freezing etching was ***,distribution and morphology of NANDS were directly *** information of particle dispersion feature and particle density can also be *** of the FETEM characterization is *** with laser scattering method,which is liable to give positive error especially for small size particle anchoring disperser,FETEM characterization can give more accurate measurement of particle ***,FETEM can give dispersion feature of nanoparticle in non-aqueous medium.

关键词： non-aqueous nano-dispersion system dispersion state in-situ characterization freeze-etching laser scattering method

An N/4 fixed-point duality quantum search algorithm

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中国科学：物理学、力学、天文学英文版 2010年第9期53卷 1765-1768页

作者： HAO Liang1,LIU Dan2 & LONG GuiLu1,3 1Key Laboratory for Atomic and Molecular NanoSciences and Department of Physics,Tsinghua university,beijing 100084,china.2School of Sciences,Dalian Nationalities university,Dalian 116600,china.3Tsinghua National Laboratory for information Science and technology,beijing 100084,china Tsinghua university Key Laboratory for Atomic and Molecular NanoSciences and Department of Physics Beijing China (GRID:grid.12527.33) (ISNI:***) Dalian Nationalities university School of Sciences Dalian China (GRID:grid.440687.9) Tsinghua university Key Laboratory for Atomic and Molecular NanoSciences and Department of Physics Beijing China (GRID:grid.12527.33) (ISNI:***) Tsinghua National Laboratory for information Science and technology Beijing China (GRID:grid.12527.33) (ISNI:***)

Here a fixed-point duality quantum search algorithm is *** algorithm uses iteratively non-unitary operations and measurements to search an unsorted *** the marked item is found,the algorithm stops *** algorithm uses a constant non-unitary operator,and requires N/4 steps on average(N is the number of data from the database) to locate the marked *** implementation of this algorithm in a usual quantum computer is also demonstrated.

关键词： fixed-point search algorithm duality quantum computing the N4 duality search algorithm

Joint Optimization of Satisfaction Index and Spectrum Efficiency with Cache Restricted for Resource Allocation in Multi-Beam Satellite Systems

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china.Communications 2019年第2期16卷 189-201页

作者： Pei Zhang Xiaohui Wang Zhiguo Ma Junde Song School of computer Science Beijing University of Posts and Telecommunications china.Academy of information and Communications technology

Dynamic resource allocation(DRA) is a key technology to improve system performances in GEO multi-beam satellite systems. And, since the cache resource on the satellite is very valuable and limited, DRA problem under restricted cache resources is also an important issue to be studied. This paper mainly investigates the DRA problem of carrier resources under certain cache constraints. What's more, with the aim to satisfy all users' traffic demands as more as possible, and to maximize the utilization of the bandwidth, we formulate a multi-objective optimization problem(MOP) where the satisfaction index and the spectrum efficiency are jointly optimized. A modified strategy SA-NSGAII which combines simulated annealing(SA) and non-dominated sorted genetic algorithm-II(NSGAII) is proposed to approximate the Pareto solution to this MOP problem. Simulation results show the effectiveness of the proposed algorithm in terms of satisfaction index, spectrum efficiency, occupied cache, and etc.

关键词： GEO multi-beam satellite system dynamic resource allocation SA-NSGAII cache satisfaction index spectrum efficiency

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高安全性混沌同步保密通信方案设计

通信学报 2003年第2期24卷 44-50页

作者：翁贻方鞠磊北京工商大学信息工程学院北京100037

设计了一种以主动-被动同步机制为基础的混沌同步保密通信方案,方案提出了获取混沌变量中对参数敏感的信息和改善相关特性的方法,得到满足安全性要求的新变量,并用于对被加密信号进行调制。用Lorenz系统进行计算机仿真通信实验和特性分... 详细信息

设计了一种以主动-被动同步机制为基础的混沌同步保密通信方案,方案提出了获取混沌变量中对参数敏感的信息和改善相关特性的方法,得到满足安全性要求的新变量,并用于对被加密信号进行调制。用Lorenz系统进行计算机仿真通信实验和特性分析的结果表明,本方案同步特性优良,信号恢复精度高,安全性比原方案有明显提高。

关键词：混沌同步保密通信敏感性安全性

Dynamic Game Model of E-commerce——based on the perspective of information asymmetry

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Dynamic Game Model of E-commerce——based on the perspective...

2011 IEEE 2nd International Conference on Computing, Control and Industrial engineering(CCIE 2011)

作者： Hanpo Hou School of business beijing technology and business university beijing, china.Jing Wen School of business beijing technology and business university beijing, china

Based on the perspective of information asymmetry, this paper uses game theory to construct a model, focusing on phenomena of concealing and cheating which are common in E-commerce between buyers and sellers in the process of transaction. Under the premise of setting participants, utility function and external environment, we take each equilibrium solution from signaling game and game of complete information to form a comparative analysis. As a result, we find out that lower level of information asymmetry do improve overall effectiveness level of the industry, and generate a positive impact on the efficiency of transaction;last but not least, governmental control plays a crucial regulatory function.

关键词： information asymmetry E-commerce game

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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 university,beijing 100084,china.2 School of computer Science and Informatics,Cardiff university,Wales CF24 3AA,UK Department of computer Science and technology Tsinghua University School of computer Science and Informatics Cardiff University

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

Semantic Focused Crawler Based On Q-Learning and Bayes Classifier

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Semantic Focused Crawler Based On Q-Learning and Bayes Class...

Remote Monitoring and Diagnosis System for High-speed Wire Rolling Mills

2010 3rd IEEE International Conference on computer Science and information technology—ICCSIT 2010

作者： Dong Chen College of Electronic information and Control engineering beijing university of technology beijing china.Fang Liying Yan Jianzhuo College of Electronic information and Control engineering beijing university of technology Shi Bin College of Electronic information and Control engineering beijing university of technology beijing china

Semantic focused crawler is an important part of semantic vertical search *** is receiving increasing attention as a well founded alternative to search web with the problem of locating topical resource on entire *** order to retrieval documents related to a given topic,in this paper,we propose QBLP Algorithm which enable crawler adaptive with the changing *** feature makes it possible to change behavior of focused crawler according to the particular environment and its relationships with the given input parameters during the *** Exploited Q learning which features whole-life learning and repayment delay accompany with Bayes *** enables crawler to accumulate experience during the crawling and adjust strategy to achieve goal of making best decision under any *** make a comparison among QBLP,Best First and Breath *** to statistics from experiments,We find that QBLP is superior on precision than others in long time crawling.

关键词： focused crawler Semantic web Q-Learning Bayes classifier

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武汉理工大学学报 2006年第S2期28卷 612-616页

作者： CUI Lingli ZHANG Jianyu DING Fang GAO Lixin WANG Dapeng (College of Mechanical engineering and Applied Electronics technology,beijing university of technology,Advanced Manufacturing technology,The Key Laboratory of beijing Municipality,beijing 100022,china College of Mechanical engineering and Applied Electronics technology Beijing University of TechnologyAdvanced ManufacturingTechnologyThe Key Laboratory of Beijing MunicipalityBeijing 100022China

Traditional fault diagnosis systems of rolling mills mostly use single machine monitoring net,which leads the re- al-time data running only in the enterprise locally and can not monitor and manage the high-speed wire rolling mills between units, workshops and factories concentratedly.A new-type structure of remote diagnosis system for high-speed wire rolling mills is pre- sented in this *** signal processing,computer network and remote diagnosis etc techniques are used to predictive maintenance manage the rolling mills units in this *** new structure reinforced the remote feedback function,made up the existing fault diagnosis systems’ insufficiency in the extension and the function,promoted resource sharing and avoided the repeat develop- *** remote diagnosis example shows that the system can monitor and diagnose the fault information of remote machine timely and effectively.

关键词： rolling mills fault diagnosis remote monitoring remote diagnosis