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An architecture for mobile database management system

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Journal of university of science and technology Beijing 2002年第2期9卷 156-160页

作者： Dong li and Yucai Feng computer school, huazhong university of science and technology, wuhan 43.074, china computer school Huazhong University of Science and Technology Wuhan 430074 China

In order to design a new kind of mobile database management system (DBMS)more suitable for mobile computing than the existent DBMS, the essence of database systems in mobilecomputing is analyzed. An opinion is introduced that the mobile database is a kind of dynamicdistributed database, and the concept of virtual servers to translate the clients' mobility to theservers' mobility is proposed. Based on these opinions, a kind of architecture of mobile DBMS, whichis of versatility, is presented. The architecture is composed of a virtual server and a local DBMS,the virtual server is the kernel of the architecture and its functions are described. Eventually,the server kernel of a mobile DBMS prototype is illustrated.

关键词： mobile database dynamic distributed database DBMS architecture virtual server data region

Cubic surface fitting to image by combination

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science china(Information sciences) 2010年第7期53卷 1287-1295页

作者： li XueMei1, ZHANG Caiming1,2, YUE YiZhen1 & WANG KunPeng1 1school of computer science and technology, Shandong university, Jinan 250101, china 2school of computer science and technology, Shandong Economics university, Jinan 250014, china 1. school of computer science and technology Shandong University Jinan 250101 China2. School of Computer Science and Technology Shandong Economics University Jinan 250014 China

We present a new method for constructing a fitting surface to image data. The new method is based on a supposition that the given image data are sampled from an original scene that can be represented by a surface defined by piecewise quadratic polynomials. The surface representing the original scene is known as the original surface in this paper. Unlike existing methods, which generally construct the fitting surface to the original surface using image data as interpolation data, the new method constructs the fitting surface using the image data as constraints to reverse the sampling process, which improves the approximation precision of the fitting surface. Associated with each data point and its near region, the new method constructs a quadratic polynomial patch locally using the sampling formula as constraint. The quadratic patch approximates the original surface with a quadratic polynomial precision. The fitting surface which approximates the original surface is formed by the combination of all the quadratic polynomial patches. The experiments demonstrate that compared with Bi-cubic and Separable PCC methods, the new method produced resized images with high precision and good quality.

关键词： surface fitting quadratic polynomial image resizing reversing

Clustering-based hyperspectral band selection using sparse nonnegative matrix factorization

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Journal of Zhejiang university-science C(computers and Electronics) 2011年第7期12卷 542-549页

作者： Ji-ming li 1,2,Yun-tao QIAN 1 (1 school of computer science and technology,Zhejiang university,Hangzhou 310027,china) (2 Zhejiang Police College,Hangzhou 310053,china) school of computer science and technology Zhejiang University Zhejiang Police College

Hyperspectral imagery generally contains a very large amount of data due to hundreds of spectral *** selection is often applied firstly to reduce computational cost and facilitate subsequent tasks such as land-cover classification and higher level image *** this paper,we propose a new band selection algorithm using sparse nonnegative matrix factorization (sparse NMF).Though acting as a clustering method for band selection,sparse NMF need not consider the distance metric between different spectral bands,which is often the key step for most common clustering-based band selection *** imposing sparsity on the coefficient matrix,the bands' clustering assignments can be easily indicated through the largest entry in each column of the *** results showed that sparse NMF provides considerable insight into the clustering-based band selection problem and the selected bands are good for land-cover classification.

关键词： Hyperspectral Band selection Clustering Sparse nonnegative matrix factorization

Spiral waves in CIMA model and its LBGK simulation

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Communications in Nonlinear science and Numerical Simulation 2001年第2期6卷 68-73页

作者： Qing li, Chuguang ZHENG and Nengchao WANG College of computer science and technology, huazhong university of science and technology, wuhan 43.074, china e-mail: qingli @ public. *** State Key Laboratory of Coal Combustion, huazhong university College of computer science and technology Huazhong University of Science and Technology Wuhan 430074 China State Key Laboratory of Coal Combustion Huazhong University of Science and Technology Wuhan 430074 China Parallel Computation Institute Huazhong University of Science and Technology Wuhan 430074 China

Two type of structures-Turing patterns and spiral waves-are obtained in chloride-iodide-malonic acid (CIMA) reaction-diffusion model by using lattice Bhatnagar-Gross-Krook (LBGK) method.

关键词： lattice Boltzmann method reaction-diffusion Turing patterns spiral waves

Basin filling algorithm for the circular packing problem with equilibrium behavioral constraints

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science china(Information sciences) 2010年第5期53卷 885-895页

作者： liU JingFa1& li Gang2 1school of computer and Software, Nanjing university of Information science & technology, Nanjing 210044, china 2school of Mathematics and Physics, Nanjing university of Information science & technology, Nanjing 210044, china 1. school of computer and Software Nanjing University of Information Science & Technology Nanjing 210044 China2. School of Mathematics and Physics Nanjing University of Information Science & Technology Nanjing 210044 China

With the background of the satellite module layout design, the circular packing problem with equilibrium behavioral constraints is a layout optimization problem and NP-hard problem in math. For lack of a powerful optimization method, this problem is hard to solve. The energy landscape paving (ELP) method is a class of stochastic global optimization algorithms based on the Monte Carlo sampling. Based on the quasiphysical strategy and the penalty function method, the problem is converted into an unconstrained optimization problem. Here by combining the improved ELP method, the gradient method based on local search and the heuristic configuration update mechanism, a new global search algorithm, basin filling algorithm, is put forward. The numerical results show that the proposed algorithm is effective to solving the circular packing problem with equilibrium behavioral constraints, and is easy to be popularized to other layout optimization problems.

关键词： equilibrium behavioral constraints packing problem layout optimization

Registering Different DBMSs to Panorama with CORBA

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wuhan university Journal of Natural sciences 2001年第Z1期6卷 423-431页

作者： Sarem Mudar, li Rui\|xuan, Xiao Wei\|jun, Lu Zheng\|ding school of computer science, huazhong university of science and technology,wuhan 43.074, china school of computer science Huazhong University of Science and Technology Wuhan 430074 China

Recently, there is an increasing use of CORBA implementation in developing multidatabase systems. MIND and Panorama are some of the examples of multidatabase prototypes that have been implemented on the top of CORBA compliant namely ObjectBroker and VisiBroker respectively. They both aim to achieve interoperability among Oracle, Sybase and other different DBMSs through the registration of these DBMSs to them using CORBA. This registration to a CORBA based multidatabase system offers an advanced way in achieving *** first introduce Panorama multidatabase system and discuss the basic implementation decisions in registering different DBMSs using the CORBA compliant ORB, namely VisiBroker to this system. Then, it aims to discuss the method we've used in registering different DBMSs to our designed multidatabase system Panorama. A detailed discussion about the registration of Oracle8 and Sybase is given. And finally, a conclusion and the future work for this system have been given.

关键词： heterogeneity CORBA interoperability multidatabase system

A new heuristic algorithm for the circular packing problem with equilibrium constraints

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science china(Information sciences) 2011年第8期54卷 1572-1584页

作者： liU JingFa 1,2,li Gang 3 & GENG HuanTong 1 1 school of computer and Software,Nanjing university of Information science & technology,Nanjing 210044,china 2 Network Information Center,Nanjing university of Information science & technology, Nanjing 210044,china 3 school of Mathematics and Physics,Nanjing university of Information science & technology,Nanjing 210044,china 1. school of computer and Software Nanjing University of Information Science & Technology Nanjing 210044 China2. Network Information Center Nanjing University of Information Science & Technology Nanjing 210044 China3. School of Mathematics and Physics Nanjing University of Information Science & Technology Nanjing 210044 China

The circular packing problem with equilibrium constraints is an optimization problem about simplified satellite module layout design.A heuristic algorithm based on tabu search is put forward for solving this *** algorithm begins from a random initial configuration and applies the gradient method with an adaptive step length to search for the minimum energy *** jump out of the local minima and avoid the search doing repeated work,the algorithm adopts the strategy of tabu *** the process of tabu search,we improve the traditional neighboring solutions,tabu objects and the acceptance criteria of the current solution *** test two sets of benchmarks consisting of 11 representative instances from the current *** numerical results show that the proposed algorithm breaks the records in seven out of 11 instances,and obtains the optimal solutions for the other four instances.

关键词： equilibrium constraints packing problem heuristic algorithm tabu search layout optimization

A heuristic algorithm for cube packing with time schedule

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science china(Information sciences) 2010年第1期53卷 18-29页

作者： li Wei1, HUANG WenQi2, JIANG DongChen1 & liU XiangLong1 1State Key Laboratory of Software Development Environment, Beihang university, Beijing 100191, china 2school of computer science and technology, huazhong university of science and technology, wuhan 43.074, china 1. State Key Laboratory of Software Development Environment Beihang University Beijing 100191 China2. School of Computer Science and Technology Huazhong University of Science and Technology Wuhan 430074 China

Packing problem has been proved to be an NP-hard problem. Many algorithms such as simulation annealing algorithm, genetic algorithm and other heuristic algorithms have been proposed to solve twodimensional and three-dimensional packing problem. To solve the cube packing problem with time schedule, this paper first introduces some concepts such as packing level, space distance and average neighbor birth order and then proposes a greedy algorithm. The algorithm tries every feasible corner greedily to calculate the space utilization, packing level, space distance, average neighbor birth order of this placement, and chooses the best placement according to these criteria. Theoretical analysis indicates that the time complexity of this algorithm is O(A2B2C2T 2n5). The experiments show that the average space utilization of non-guillotine cutting test cases is 98.81%, and the average space utilization of guillotine cutting test cases achieves 99.87%. Furthermore, optimal solutions of more than half cases are achieved by this algorithm. The experimental results show that this algorithm can solve the problem of cube packing with time schedule effectively and effciently.

关键词： cube packing problem time schedule packing level space distance average neighbor birth order

Measurement technology for Engine Assembly

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武汉理工大学学报 2006年第S3期28卷 978-982页

作者： GAO li~1 ZHENG Zeyu~2 DAI Shangping~1 (1.Department of computer science,Central china Normal university,wuhan 430079,china 2.school of computer science and technology,huazhong university of science and technology,wuhan 43.074,china) Department of computer science Central China Normal UniversityWuhan 430079China school of computer science and technology Huazhong University of Science and TechnologyWuhan 430074China

In many industrial,it is often necessary to analyze the engine *** paper introduces three kinds of new technologies on the assembly line of engine in recent years,it have played the positive role in improving the qual... 详细信息

关键词： quality control measured engine assembly