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Automatic Circuit Extractor for HDL Description Using Program Slicing

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Journal of Computer Science & Technology 2004年第5期19卷 718-728页

作者： TunLi YangGuo Si-KunLi schoolofcomputerscienceandtechnology NationalUniversityofDefenseTechnologyChangsha410073P.R.China

Design extraction and reduction have been extensively used in modern VLSI design process. The extracted and reduced design can be efficiently processed by various applications, such as formal verification, simulation, automatic test pattern generation (ATPG), etc. This paper presents a new circuit extraction method using program slicing technique, and develops an elegant theoretical basis based on program slicing for circuit extraction from Verilog description. The technique can obtain a chaining slice for given signals of interest. Compared with related researches, the main advantages of the method include that it is fine grain, it has no hardware description language (HDL) coding style limitation; it is precise and is capable of dealing with various Verilog constructions. The technique has been integrated with a commercial simulation environment and incorporated into a design process. The results of practical designs show the significant benefits of the approach.

关键词： program slicing chaining slice process dependence graph circuit extraction VLSI functional verification

Approximation Algorithm for Bottleneck Steiner Tree Problem in the Euclidean Plane

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Journal of Computer Science & Technology 2004年第6期19卷 791-794页

作者： Zi-MaoLi Da-MingZhu Shao-HanMa schoolofcomputerscienceandtechnology ShandongUniversityJinan250061P.R.China

A special case of the bottleneck Steiner tree problem in the Euclidean plane was considered in this paper. The problem has applications in the design of wireless communication networks, multifacility location, VLSI routing and network routing. For the special case which requires that there should be no edge connecting any two Steiner points in the optimal solution, a 3-restricted Steiner tree can be found indicating the existence of the performance ratio root2. In this paper, the special case of the problem is proved to be NP-hard and cannot be approximated within ratio root2. First a simple polynomial time approximation algorithm with performance ratio root3 is presented. Then based on this algorithm and the existence of the 3-restricted Steiner tree, a polynomial time approximation algorithm with performance ratio-root2 + epsilon is proposed, for any epsilon > 0.

关键词： bottleneck Steiner tree approximation algorithm performance ratio algorithm design and analysis

Lattice Bhatnagar—Gross—Krook Simulation of Stratified Backward—Facing Step Flow

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Chinese Physics Letters 2002年第12期19卷 1831-1834页

作者：郭卫斌施保昌等 schoolofcomputerscienceandtechnology HuazhongUniversityofScienceandTechnologyWuhan430074 ParallelComputingInstitute HuazhongUniversityofScienceandTechnologyWuhan430074

We perform a numerical simulation for steady stably-stratified flow over a two-dimensional backward-facing step with the Froude number of 16/9, the Reynolds number of 800 and the Prandtl number of 1.0 by using a newly developed thermal lattice Bhatnagar-Gross-Krook model. A detailed analysis is presented. Excellent agreement between the present results and other numerical data shows that the lattice Boltzmann method is an efficient simulation method for complex flows.

关键词： Prandtl number

A High-Speed Information Retrieval System

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Wuhan University Journal of Natural Sciences 2004年第4期9卷 425-428页

作者： SHIShu-dong LIZhi-tang schoolofcomputerscienceandtechnology HuazhongUniversityofScienceandTechnologyWuhan430074HuheiChina schoolofcomputerscienceandtechnology HuazhongUniversityofScienceandTechnologyWuhan430074HuheiChina

We cleveloped a high-speed information retrieval system. The system hased on the IXP 2800 is one of the dedicute device. The velocity of the information retrieval is 6.8 Gb/s. The protocol support Telnet, FTP, SMTP, POP3 etc. various networks protocols. The information retrieval supports the key word and the natural language process. This paper explains the hardware system, software system and the index of the performance. Key words network processor - IXP2800 - information retrieval - IXA CLC number TP 309 Foundation item: Supported by the National Natural Science Foundation of China (69873016 & 69972017) and the National High Technology Development Program of China (863-301-06-1)Biography: SHI Shu-dong (1963-), male, Ph. D. candidate, research direction: network & information security.

关键词： network processor IXP2800 information retrieval IXA

Fast Computation of Sparse Data Cubes with Constraints

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Wuhan University Journal of Natural Sciences 2004年第2期9卷 167-172页

作者： FengYu-cai ChenChang-qing FengJian-lin XiangLong-gang schoolofcomputerscienceandtechnology HuazhongUniversityofScienceandTechnologyWuhan430074HubeiChina

For a data cube there are always constraints between dimensions or among attributes in a dimension, such as functional dependencies. We introduce the problem that when there are functional dependencies, how to use them to speed up the computation of sparse data cubes. A new algorithm CFD (Computation by Functional Dependencies) is presented to satisfy this demand. CFD determines the order of dimensions by considering cardinalities of dimensions and functional dependencies between dimensions together, thus reduce the number of partitions for such dimensions. CFD also combines partitioning from bottom to up and aggregate computation from top to bottom to speed up the computation further. CFD can efficiently compute a data cube with hierarchies in a dimension from the smallest granularity to the coarsest one. Key words sparse data cube - functional dependency - dimension - partition - CFD CLC number TP 311 Foundation item: Supported by the E-Government Project of the Ministry of Science and Technology of China (2001BA110B01)Biography: Feng Yu-cai (1945-), male, Professor, research direction: database system.

关键词： sparse data cube functional dependency dimension partition CFD

Personification algorithm for protein folding problem:Improvements in PERM

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Chinese Science Bulletin 2004年第19期49卷 2092-2096页

作者： HUANGWenqi LUZhipeng schoolofcomputerscienceandtechnology HuazhongUniversityofScienceandTechnologyWuhan430074China

PERM is the most efficient approach for solv- ing protein folding problem based on simple lattice model. In this article a personification explanation of PERM is pro- posed. A new version of PERM, population control algorithm with two main improvements is presented: one is that it is able to redefine the weight and its predicted value in PERM, and the other is that it is able to unify the calculation of weight when choosing possible branches. The improved PERM is more efficient than the previous version; specifi- cally it can find the known lowest energy states for the four well-known difficult instances and is generally several to hundreds times faster than PERM. It is noteworthy that with the improved PERM we found new lowest energy configura- tions of three of the four difficult problems missed in previ- ous papers.

关键词：蛋白质折叠结构研究拟人化算法 PERM 点阵模型种群控制算法

Lattice—BGK simulation of a two—dimensional channel flow around a square cylinder

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Chinese Physics B 2003年第1期12卷 67-74页

作者：郭卫斌王能超等 schoolofcomputerscienceandtechnology HuazhongUniversityofScienceandTechnologyWuhan430074China schoolofcomputerscienceandtechnology HuazhongUniversityofScienceandTechnologyWu

The confined flow around a square cylinder mounted inside a two-dimensional channel (blockage ratio3 = 1/8) was investigated in detail by a newly developed incompressible nonuniform lattice-BGK model. It is found that the vortex shedding behind the cylinder induces periodicity in the flow field, and the periodicity of the flow will lose for Re ＞300.A detailed analysis for a range of Reynolds numbers between 1 and 500 was presented. Quantitative comparisons with other methods show that the model gives accurate results for complex flows.

关键词： lattice-BGK method square cylinder Strouhal number drag coefficient

Data Hiding and Security for XMLDatabase: A TRBAC-Based Approach

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Wuhan University Journal of Natural Sciences 2005年第1期10卷 293-296页

作者： ZHANGWan-song SUNWei LIUDa-xin schoolofcomputerscienceandtechnology HarbinEngineeringUniversityHarbin150001HeilongjiangChna

In order to cope with varying protection granularity levels of XML(extensible Markup Language) documents, we propose a TXAC (Two-level XML. Access Control) framework,in which an extended TRBAC ( Temporal Role-Based Access Control) approach is proposed to deal withthe dynamic XML data With different system components, LXAC algorithm evaluates access requestsefficiently by appropriate access control policy in dynamic web environment. The method is aflexible and powerful security system offering amulti-level access control solution.

关键词： XML data access control data security

Wavelet Energy Feature Extraction and Matching for Palmprint Recognition

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Journal of Computer Science & Technology 2005年第3期20卷 411-418页

作者： Xiang-QianWu Kuan-QuanWang DavidZhang schoolofcomputerscienceandtechnology HarbinInstituteofTechnologyHarbin150001P.R.China BiometricsResearchCentre DepartmentofComputingHongKongPolytechnicUniversity

According to the fact that the basic features of a palmprint, includingprincipal lines, wrinkles and ridges, have different resolutions, in this paper we analyzepalmprints using a multi-resolution method and define a novel palmprint feature, which calledwavelet energy feature (WEF), based on the wavelet transform. WEF can reflect the wavelet energydistribution of the principal lines, wrinkles and ridges in different directions at differentresolutions (scales), thus it can efficiently characterize palmprints. This paper also analyses thediscriminabilities of each level WEF and, according to these discriminabilities, chooses a suitableweight for each level to compute the weighted city block distance for recognition. The experimentalresults show that the order of the discriminabilities of each level WEF, from strong to weak, is the4th, 3rd, 5th, 2nd and 1st level. It also shows that WEF is robust to some extent in rotation andtranslation of the images. Accuracies of 99.24% and 99.45% have been obtained in palmprintverification and palmprint identification, respectively. These results demonstrate the power of theproposed approach.

关键词： biometrics palmprint recognition wavelet energy feature weighted cityblock distance