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Tsinghua Science and Technology

Issue 5 • Oct. 2009

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Displaying Results 1 - 20 of 20
  • [Front cover]

    Publication Year: 2009, Page(s): c1
    IEEE is not the copyright holder of this material | PDF file iconPDF (155 KB)
    Freely Available from IEEE
  • Contents

    Publication Year: 2009, Page(s): 1
    IEEE is not the copyright holder of this material | PDF file iconPDF (91 KB)
    Freely Available from IEEE
  • A fast leak locating method based on wavelet transform

    Publication Year: 2009, Page(s):551 - 555
    Cited by:  Papers (2)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (288 KB)

    The problem of leak location is actually a time delay estimation (TOE) problem. Since most existing TDE methods may encounter the problem of high computational complexity when used for online leak location. This paper presents a fast leak locating method based on wavelet transform (WT). The method first gets a rough estimate of the time delay from the WT coefficients of the pressure signals at the... View full abstract»

    Open Access
  • Multistep linear programming approaches for decoding low-density parity-check codes

    Publication Year: 2009, Page(s):556 - 560
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (280 KB)

    The problem of improving the performance of linear programming (LP) decoding of low-density parity-check (LDPC) codes is considered in this paper. A multistep linear programming (MLP) algorithm was developed for decoding LDPC codes that includes a slight increase in computational complexity. The MLP decoder adaptively adds new constraints which are compatible with a selected check node to refine t... View full abstract»

    Open Access
  • Architecture design of a variable length instruction set VLIW DSP

    Publication Year: 2009, Page(s):561 - 569
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (1095 KB)

    The cost of the central register file and the size of the program code limit the scalability of very long instruction word (VLIW) processors with increasing numbers of functional units. This paper presents the architectural design of a six-way VLIW digital signal processor (DSP) with clustered register files. The architecture uses a variable length instruction set and supports dynamic instruction ... View full abstract»

    Open Access
  • Bit-depth scalable coding using a perfect picture and adaptive neighboring filter

    Publication Year: 2009, Page(s):570 - 574
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (437 KB)

    Bit-depth scalability is a new research field in the on-going scalable extension of the H.264/AVC (SVC) video coding standard. The key point is to accurately predict the enhancement layer, whose bit depth is 10 or more, from the 8 bit base layer. An improved inter-layer prediction scheme for bit-depth scalability was developed that ensures compatibility with the standard and improves the encoding ... View full abstract»

    Open Access
  • Efficiency of cache mechanism for network processors

    Publication Year: 2009, Page(s):575 - 585
    Cited by:  Papers (2)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (684 KB)

    With the explosion of network bandwidth and the ever-changing requirements for diverse network-based applications, the traditional processing architectures, i.e., general purpose processor (GPP) and application specific integrated circuits (ASIC) cannot provide sufficient flexibility and high performance at the same time. Thus, the network processor (NP) has emerged as an alternative to meet these... View full abstract»

    Open Access
  • Smart image sensor with integrated low complexity image processing for wireless endoscope capsules

    Publication Year: 2009, Page(s):586 - 592
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (1274 KB)

    A smart image sensor was developed which integrates a digital pixel image sensor array with an image processor, designed for wireless endoscope capsules. The camera-on-a-chip architecture and its on-chip functionality facilitate the design of the packaging and power consumption of the integrated capsule. The power reduction techniques were carried out at both the architectural and circuit level. G... View full abstract»

    Open Access
  • Reliable remote-monitoring electrochemical potentiostat for glucose measurements

    Publication Year: 2009, Page(s):593 - 600
    Cited by:  Patents (1)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (567 KB)

    Electrochemical methods have been widely used in the chemical and pharmaceutical industries, which require accurate concentration measurements, chemical reaction detections and analyses. The electrochemical potentiostat, the core element in electrochemical instruments, have been discussed as a hot topic addressing the difficulty of applying high-precision constant voltage and picoampere current me... View full abstract»

    Open Access
  • Digital 1 V 82 μW pseudo-two-stage Class-AB OTA

    Publication Year: 2009, Page(s):601 - 605
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (480 KB)

    A low power digital operational transconductance amplifier (OTA) was developed for low voltage switched capacitor applications. The OTA has a high slew rate (SR) and a large open loop gain with a differential pseudo-two-stage Class-AB structure. A fully compensated depletion mode capacitor is used in the switched capacitor common mode feedback block instead of a metal-insulator-metal (MIM) capacit... View full abstract»

    Open Access
  • Improved grapheme-to-phoneme conversion for mandarin TTS

    Publication Year: 2009, Page(s):606 - 611
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (303 KB)

    Several methods were developed to improve grapheme-to-phoneme (G2P) conversion models for Chinese text-to-speech (TTS) systems. The critical problem of data sparsity was handled by combining approaches. First, a text-selection method was designed to cover as many G2P text corpus contexts as possible. Then, various data-driven modeling methods were used with comparisons to select the best method fo... View full abstract»

    Open Access
  • Dynamic simulations of nonlinear multi-domain systems based on genetic programming and bond graphs

    Publication Year: 2009, Page(s):612 - 616
    Cited by:  Papers (2)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (298 KB)

    A dynamic simulation method for non-linear systems based on genetic programming (GP) and bond graphs (8G) was developed to improve the design of nonlinear multi-domain energy conversion systems. The genetic operators enable the embryo bond graph to evolve towards the target graph according to the fitness function. Better simulation requires analysis of the optimization of the eigenvalue and the fi... View full abstract»

    Open Access
  • Feedforward control of a 3-D physiological articulatory model for vowel production

    Publication Year: 2009, Page(s):617 - 622
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (837 KB)

    A three-dimensional (3-D) physiological articulatory model was developed to account for the biomechanical properties of the speech organs in speech production. Control of the model to investigate the mechanism of speech production requires an efficient control module to estimate muscle activation patterns, which is used to manipulate the 3-D physiological articulatory model, according to the desir... View full abstract»

    Open Access
  • A unified framework for multilingual text-to-speech synthesis with SSML specification as interface

    Publication Year: 2009, Page(s):623 - 630
    Cited by:  Papers (2)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (557 KB)

    This paper describes the design of a unified framework for a multilingual text-to-speech (TTS) synthesis engine — Crystal. The unified framework defines the common TTS modules for different languages and/or dialects. The interfaces between consecutive modules conform to the speech synthesis markup language (SSML) specification for standardization, interoperability, multilinguality, and exte... View full abstract»

    Open Access
  • Friction effects in pedestrian headform impacts with engine hoods

    Publication Year: 2009, Page(s):631 - 638
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (12922 KB)

    In the pedestrian headform impact test mandated by the European pedestrian safety requirements, the contact friction between the headform and the engine hood affects the headform kinematics and head injury criterion (HIC) to some extent. This study shows that the friction effect is more significant with child headform impact than with adult headform impact and the relative angle between the headfo... View full abstract»

    Open Access
  • MECHANICAL ENGINEERING 
  • Modeling and experimental study of PEM fuel cell transient response for automotive applications

    Publication Year: 2009, Page(s):639 - 645
    Cited by:  Papers (1)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (3692 KB)

    This paper presents an analysis of the dynamic response of a low pressure proton exchange membrane (PEM) fuel cell stack to step changes in load, which are characteristic of automotive fuel cell system applications. The goal is a better understanding of the electrical and electrochemical processes when accounting for the characteristic cell voltage response during transients. The analysis and expe... View full abstract»

    Open Access
  • Invariants for parallel mapping

    Publication Year: 2009, Page(s):646 - 654
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (591 KB)

    This paper analyzes the geometric quantities that remain unchanged during parallel mapping (i.e., mapping from a reference curved surface to a parallel surface with identical normal direction). The second gradient operator, the second class of integral theorems, the Gauss-curvature-based integral theorems, and the core property of parallel mapping are used to derive a series of parallel mapping in... View full abstract»

    Open Access
  • A method for reducing disorientation in hypermedia educational systems

    Publication Year: 2009, Page(s):655 - 662
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (270 KB)

    Learners in hypermedia educational systems (HES) often become disorientated and experience cognitive overhead. This study presents a method for reducing disorientation in HES. The study uses two usability methods, retrospective thinking aloud (RTA) and performance measure (PM), to find usability problems in HES that impact participant disorientation. The participants had field independent (FI) and... View full abstract»

    Open Access
  • Optimum kinematic design of the 4R 2-DOF parallel mechanism

    Publication Year: 2009, Page(s):663 - 668
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (11977 KB)

    This paper analyzes the kinematic optimization design of the 4R 2-DOF parallel mechanism taking into account the force transmissibility. Three indices are introduced to reflect the force transmissibility. Based on these indices and their performance charts, the optimization design process with respect to the workspace is presented in detail. The results show that the designed mechanism is not only... View full abstract»

    Open Access
  • Infection functions for virus propagation in computer networks: An empirical study

    Publication Year: 2009, Page(s):669 - 676
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (822 KB)

    There has been an increasing amount of interest in modeling virus propagation in recent years. However, the group-based infection mechanism of computer viruses is not well understood and the selection of infection function in virus propagation modeling has not been well studied. This paper describes a point-to-group (P2G) infection mode to describe virus propagation in networks with information sh... 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.

Full Aims & Scope

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