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Tsinghua Science and Technology

Issue 2 • April 2012

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Displaying Results 1 - 14 of 14
  • [Front cover]

    Publication Year: 2012, Page(s): c1
    IEEE is not the copyright holder of this material | PDF file iconPDF (1330 KB)
    Freely Available from IEEE
  • Contents

    Publication Year: 2012, Page(s): 1
    IEEE is not the copyright holder of this material | PDF file iconPDF (66 KB)
    Freely Available from IEEE
  • SPECIAL SECTION ON MOBILE AND UBIQUITOUS MULTIMEDIA 
  • Intermedia-based video adaptation system: Design and implementation

    Publication Year: 2012, Page(s):113 - 127
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (1390 KB)

    Video adaptation is a promising technique to bridge the gap between network status, device capabilities, and user preferences in pervasive media applications. However, conventional adaptation frameworks based on either transcoding or multiple pre-transcoding are not able to accommodate large numbers of users with diversified applications. This paper introduces an intermediate video description cal... View full abstract»

    Open Access
  • Semi-global depth estimation algorithm for mobile 3-D video applications

    Publication Year: 2012, Page(s):128 - 135
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (1789 KB)

    Three-dimensional (3-D) video applications, such as 3-D cinema, 3DTV, and Free Viewpoint Video (FVV) are attracting more attention both from the industry and in the literature. High accuracy of depth video is a fundamental prerequisite for most 3-D applications. However, accurate depth requires computationally intensive global optimization. This high computational complexity is one of the bottlene... View full abstract»

    Open Access
  • Tracking co-evolution of behavior and relationships with mobile phones

    Publication Year: 2012, Page(s):136 - 151
    Cited by:  Papers (2)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (3789 KB)

    The co-evolution of social relationships and individual behavior in time and space has important implications, but is poorly understood because of the difficulty of closely tracking the everyday life of a complete community. We offer evidence that relationships and behavior co-evolve in a student dormitory, based on monthly surveys and location tracking through resident cellular phones over a peri... View full abstract»

    Open Access
  • Bid strategies of primary users in double spectrum auctions

    Publication Year: 2012, Page(s):152 - 160
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (422 KB)

    Extensive research in recent years has shown that dynamic spectrum sharing is a promising approach to address the artificial spectrum scarcity problem by improving spectrum utilization. This new communication paradigm, however, requires a well-designed spectrum allocation mechanism. This paper designs a double spectrum auction framework that allows unlicensed secondary users to obtain selected idl... View full abstract»

    Open Access
  • Throughput gain of random wireless networks with Physical-layer Network Coding

    Publication Year: 2012, Page(s):161 - 171
    Cited by:  Papers (1)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (457 KB)

    This study analyzes the impact of Physical-layer Network Coding (PNC) on the throughput of a large random wireless network, including one-dimensional and two-dimensional networks. Three different transmission schemes, (1) a traditional flow-based scheme, (2) a network coding scheme, and (3) the PNC scheme are compared to show that the PNC scheme improves wireless network throughput by a constant f... View full abstract»

    Open Access
  • Atmospheric pressure-aware seamless 3-D localization and navigation for mobile Internet devices

    Publication Year: 2012, Page(s):172 - 178
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (16560 KB)

    This paper describes a seamless three-dimensional (3-D) localization and navigation system for smartphones. The smartphone includes an atmospheric pressure sensor to measure the user's altitude that is combined with the outdoor Global Positioning System (GPS) and indoor WiFi-APs localization systems in a seamless 3-D localization system. The smartphone software also provides seamless navigation se... View full abstract»

    Open Access
  • Trust evaluation model based on behavior space classification for ad hoc networks

    Publication Year: 2012, Page(s):179 - 185
    Cited by:  Papers (1)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (822 KB)

    Trust management frameworks are used to evaluate and manage trust relationships between network nodes and enhance network security. However, trust management frameworks themselves are vulnerable to attacks. Attacks against trust management frameworks are described in this paper with a trust management framework to resist them. The trustworthiness between nodes is evaluated to classify node behavio... View full abstract»

    Open Access
  • REGULAR ARTICLES 
  • Topology control algorithm using fault-tolerant 1-spanner for wireless ad hoc networks

    Publication Year: 2012, Page(s):186 - 193
    Cited by:  Papers (2)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (1004 KB)

    A fault-tolerant 1-spanner is used to preserve all the minimum energy paths after node failures to cope with fault-tolerant topology control problems in wireless ad hoc networks. A fault-tolerant 1-spanner is a graph such that the remaining graph after node failures will not only remain connected, but also have a stretch factor of one. The fault-tolerant 1-spanner is used in a localized and distri... View full abstract»

    Open Access
  • A generic object detection using a single query image without training

    Publication Year: 2012, Page(s):194 - 201
    Cited by:  Papers (1)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (1860 KB)

    A method was developed to detect generic objects using a single query image. The query image could be a typical real image, a virtual image, or even a hand-drawn sketch of the object. Without a training process, the key problem is how to describe the object class from only one query image with no pre-segmentation or other pre-processing procedures. The method introduces densely computed Scale-Inva... View full abstract»

    Open Access
  • Hard decision directed frequency tracking for OFDM on frequency selective channel

    Publication Year: 2012, Page(s):202 - 208
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (373 KB)

    This paper presents a decision directed frequency tracking scheme to improve the spectrum efficiency of Orthogonal Frequency Division Modulation (OFDM) transmission for frequency selective channels. OFDM divides a broadband channel into parallel narrowband subchannels with different channel characteristics. The subcarriers with lower attenuation are selected to do the decision directed based frequ... View full abstract»

    Open Access
  • Identification of Chinese Materia Medicas in microscopic powder images

    Publication Year: 2012, Page(s):209 - 217
    Cited by:  Papers (1)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (1935 KB)

    This paper describes an identification system for Chinese Materia Medicas (CMMs) in microscopic powder images. The imaging processing of the microscopic powder image is very complex because of the low contrast, blurry boundaries, overlapping objects, and messy background. Therefore, the object detection must segment the significant microscopic structures from the complex image. The objects are det... View full abstract»

    Open Access
  • Modeling pitch contour of Chinese Mandarin sentences with the PENTA model

    Publication Year: 2012, Page(s):218 - 224
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (571 KB)

    In continuous speech, the pitch contour of the same syllable may vary much due to its contextual information. The Parallel Encoding and Target Approximation (PENTA) model is applied here to Mandarin speech synthesis with a method to predict pitch contours for Chinese syllables with different contexts by combining the Classification And Regression Tree (CART) with the PENTA model to improve its pre... 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