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Tsinghua Science and Technology

Issue 5 • Oct. 2007

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Displaying Results 1 - 21 of 21
  • [Front cover]

    Publication Year: 2007, Page(s): c1
    IEEE is not the copyright holder of this material | PDF file iconPDF (219 KB)
    Freely Available from IEEE
  • Contents

    Publication Year: 2007, Page(s): 1
    IEEE is not the copyright holder of this material | PDF file iconPDF (73 KB)
    Freely Available from IEEE
  • Selective smoothed finite element method

    Publication Year: 2007, Page(s):497 - 508
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (430 KB)

    The paper examines three selective schemes for the smoothed finite element method (SFEM) which was formulated by incorporating a cell-wise strain smoothing operation into the standard compatible finite element method (FEM). These selective SFEM schemes were formulated based on three selective insmoothing FEM selective with similar properties found between the number of smoothing cells in th... View full abstract»

    Open Access
  • Singular and regular implementations of the hybrid boundary node method

    Publication Year: 2007, Page(s):509 - 519
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (450 KB)

    The hybrid boundary node method (HdBNM) combines a modified function with the moving least squares approximation to form a boundary-only truly meshless method. This paper describes two implementations of the HdBNM, the singular hybrid boundary node method (ShBNM) and the regular hybrid boundary node method (RhBNM). The ShBNM and RhBNM were compared with each other, and the parameters that influenc... View full abstract»

    Open Access
  • BEM Analysis of wave propagation in a water-filled borehole in an anisotropic solid

    Publication Year: 2007, Page(s):520 - 526
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (649 KB)

    This paper describes a time-domain boundary element method developed to analyze the interactions of acoustic and elastic waves near the interfaces between water and an anisotropic elastic solid. Two models are analyzed with one being the interface between two half spaces of fluid and solid and the other being a fluid region sandwiched by half space domains of anisotropic elastic solids. Both monop... View full abstract»

    Open Access
  • Numerical simulation of the mechanical properties and failure of heterogeneous elasto-plastic materials

    Publication Year: 2007, Page(s):527 - 532
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (302 KB)

    A general numerical approach was developed to simulate the mechanical properties and the failure of heterogeneous elasto-plastic materials using statistical distributions of the material properties. An appropriate elastic-plastic constitutive relation is used to describe the material behavior and failure in each element, with a two-parameter Weibull distribution used to produce the initial heterog... View full abstract»

    Open Access
  • Improved active vibration isolation systems

    Publication Year: 2007, Page(s):533 - 539
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (318 KB)

    The control force, feedback gain, and actuator stroke of several active vibration isolation systems were analyzed based on a single-layer active vibration isolation system. The analysis shows that the feedback gain and actuator stroke cannot be selected independently and the active isolation system design must make a compromise between the feedback gain and actuator stroke. The performance of acti... View full abstract»

    Open Access
  • A numerical method for cavity identification in beams on an elastic foundation

    Publication Year: 2007, Page(s):540 - 545
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (269 KB)

    An analytical solution for the natural frequencies of a beam containing a cavity on an elastic foundation is presented. Based on the analytical solution, a numerical method for identifying cavities in the foundation is developed. The position and size of the cavities are identified by minimizing an objective function, which is formulated according to the difference between the computed and measure... View full abstract»

    Open Access
  • A modified extended Bayesian method for parameter estimation

    Publication Year: 2007, Page(s):546 - 553
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (444 KB)

    This paper presents a modified extended Bayesian method for parameter estimation. In this method the mean value of the a priori estimation is taken from the values of the estimated parameters in the previous iteration step. In this way, the parameter covariance matrix can be automatically updated during the estimation procedure, thereby avoiding the selection of an empirical parameter. Because the... View full abstract»

    Open Access
  • Large scale analysis of mechanical properties in 3-D fiber-reinforced composites using a new fast multipole boundary element method

    Publication Year: 2007, Page(s):554 - 561
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (567 KB)

    Fiber-reinforced composites are commonly used in various engineering applications. The mechanical properties of such composites depend strongly on micro-structural parameters. This paper presents a new boundary element method (BEM) for numerical analysis of the mechanical properties of 3-D fiberreinforced composites. Acceleration of the BEM is achieved by means of a fast multipole method (FMM), in... View full abstract»

    Open Access
  • FM-BEM evaluation for effective elastic moduli of microcracked solids

    Publication Year: 2007, Page(s):562 - 566
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (554 KB)

    A fast multipole boundary element method (FM-BEM) was applied for the analysis of microcracked solids. Both the computational complexity and memory requirement are reduced to O(N), where N is the number of degrees of freedom. The effective elastic moduli of a 2-D solid containing thousands of randomly distributed microcracks were evaluated using the FM-BEM. The results prove that both the differen... View full abstract»

    Open Access
  • An adaptive boundary collocation method for plate bending problems

    Publication Year: 2007, Page(s):567 - 571
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (293 KB)

    A boundary collocation method based on the least-square technique and a corresponding adaptive computation process have been developed for the plate bending problem. The trial functions are constructed using a series of the biharmonic polynomials, and the local error indicators are given by the residuals of the energy density on the boundary. I n comparison with the conventional collocation method... View full abstract»

    Open Access
  • Chaotic motion of corrugated circular plates

    Publication Year: 2007, Page(s):572 - 576
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (338 KB)

    Large deflection theory of thin anisotropic circular plates was used to analyze the bifurcation behavior and chaotic phenomena of a corrugated thin circular plate with combined transverse periodic excitation and an in-plane static boundary load. The nonlinear dynamic equation for the corrugated plate was derived by employing Galerkin's technique. The critical conditions for occurrence of the homoc... View full abstract»

    Open Access
  • Reference trajectory generation for 3-Dimensional walking of a humanoid robot

    Publication Year: 2007, Page(s):577 - 584
    Cited by:  Papers (2)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (536 KB)

    Humanoid walking planning is a complicated task because of the high number of degrees of freedom (DOFs) and the variable mechanical structure during walking. In this paper, a planning method for 3-dimensional (3-D) walking movements was developed based on a model of a typical humanoid robot with 12 DOFs on the lower body. The planning process includes trajectory generation for the hip, ankle, and ... View full abstract»

    Open Access
  • Memory efficient string matching algorithm for network intrusion management system

    Publication Year: 2007, Page(s):585 - 593
    Cited by:  Papers (1)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (346 KB)

    As the core algorithm and the most time consuming part of almost every modern network intrusion management system (NIMS), string matching is essential for the inspection of network flows at the line speed. This paper presents a memory and time efficient string matching algorithm specifically designed for NIMS on commodity processors. Modifications of the Aho-Corasick (AC) algorithm based on the di... View full abstract»

    Open Access
  • A statistical method for analysis of technical data of a badminton match based on 2-D seriate images

    Publication Year: 2007, Page(s):594 - 601
    Cited by:  Papers (3)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (539 KB)

    The use of computer vision technology to collect and analyze statistics during badminton matches or training sessions can be expected to provide valuable information to help coaches to determine which tactics should be used by a player in a given game or to improve the player's tactical training. A method based on 2-D seriate images by which statistical data of a badminton match can be obtained is... View full abstract»

    Open Access
  • Fast fractal image encoding using an improved search scheme

    Publication Year: 2007, Page(s):602 - 606
    Cited by:  Papers (2)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (459 KB)

    As fractal image encoding algorithms can yield high-resolution reconstructed images at very high compression ratio, and therefore, have a great potential for improving the efficiency of image storage and image transmission. However, the baseline fractal encoding algorithm requires a great deal of time to complete the best matching search between the range and domain blocks, which greatly limits pr... View full abstract»

    Open Access
  • Task space division and trajectory planning for a flexible macro-micro manipulator system

    Publication Year: 2007, Page(s):607 - 613
    Cited by:  Papers (1)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (422 KB)

    This paper deals with a flexible macro-micro manipulator system, which includes a long flexible manipulator and a relatively short rigid manipulator attached to the tip of the macro manipulator. A flexible macro manipulator possesses the advantages of wide operating range, high speed, and low energy consumption, but the disadvantage of a low tracking precision. The macro-micro manipulator system i... View full abstract»

    Open Access
  • High performance position control system based on SR-PM motor

    Publication Year: 2007, Page(s):614 - 619
    Cited by:  Papers (1)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (357 KB)

    A position control system was developed using a synchronous reluctance permanent magnetic (SR-PM) motor with the field oriented control (FOG). To get satisfactory control performance, a fuzzy adaptive proportion integration (PI) controller was used rather than a conventional PI controller for the position control. The controller tunes the PI parameters online with fuzzy logic, based on the error a... View full abstract»

    Open Access
  • CRC look-up table optimization for single-bit error correction

    Publication Year: 2007, Page(s):620 - 623
    Cited by:  Papers (1)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (257 KB)

    Many communication systems use the cyclic redundancy code (CRC) technique for protecting key data fields from transmission errors by enabling both single-bit error correction and multi-bit error detection. The look-up table design is very important for the error-correction implementation. This paper presents a CRC look-up table optimization method for single-bit error correction. The optimization ... View full abstract»

    Open Access
  • Pressure dependence of molar volume near the melting point in benzene

    Publication Year: 2007, Page(s):624 - 628
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (284 KB)

    The pressure dependence of the molar volume was at constant temperatures close to the melting point in benzene. The molar volume of benzene was calculated using experimental data for the thermal expansivity for constant temperatures of 25°C, 28.5°C, 40°C, and 51°C at various pressures for both the solid and liquid phases. The predictions are in good agreement with the o... View full abstract»

    Open Access

Aims & Scope

Tsinghua Science and Technology (Tsinghua Sci Technol) aims to highlight scientific achievements in computer science, electronic engineering, and other IT fields. Contributions all over the world are welcome.

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Meet Our Editors

Editor-in-Chief
Professor Jiaguang Sun
School of Software
Tsinghua University
Beijing  100084 China
journal@tsinghua.edu.cn
Phone:86-10-62771385