The 3rd COE Postdoctoral and Doctoral Researchers
Technical Presentation

Date: Thursday, June 24, 2004
Time: 13:30 - 15:30
Place: L1 Lecture room
Language: English (oral presentation), English/Japanese (question)

Program (20 mins each: 15 mins presentation and 5 min discussion)

  1. "Behavior of a MOS Domino gate affected by a Gate-Oxide Short"
    マリアン コムツ ( コンピューター設計学講座 : PD )
    Mariane Comte ( Computer Design and Test Lab. : PD )

    [Abstract]
    Testing aims at guarantying the correct operation of integrated circuits (IC). Due to both the reduction of dimensions and voltage amplitudes on the one hand, and the increase of function complexity on the other hand, nowadays IC have become extremely sensitive to the impact of defects. In particular, Gate-Oxide Shorts (GOS) strongly affect the production yield of deeply submicronic circuits and also often disrupt the operation of IC during their lifetime. Nevertheless, such failures remain extremely difficult to detect. In order to find effective solutions to detect these defects, it is necessary in the first place to study in detail their impact on the behavior of IC architectures, depending on the circuit specificity. To this aim, we have studied the impact of a GOS affecting successively the different transistors of an elementary Domino Gate. Although Domino gates exhibit lower noise margins compared to full CMOS logic gates, predisposing to a higher sensitivity to GOS effects, detecting GOS seems to remain a challenge even for Domino cells. A very interesting state of high impedance appears in a particular case. The results of the behavioral study of GOS influence in a Domino gate will be presented.

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  2. "Annotation-Based Assistance System for Unmanned Helicopter with Wearable Augmented Reality Environment"
    小枝 正直 ( ロボティクス講座 : D3 )
    Masanao Koeda ( Robotics Lab. : D3 )

    [Abstract]
    In this presentation, we introduce an annotation-based assistance system for an unmanned helicopter with an wearable augmented reality environment. In this system, an operator controls the helicopter remotely while watching the helicopter's views with some annotations through a head mounted display with a laptop PC in a backpack. Annotations assist the operation indicating some conditions of the helicopter and a name of buildings nearby. The position and the attitude of the helicopter are measured by GPS and a gyroscope, and sent to the operator's PC via a wireless LAN. We have carried out an experiment using the system around our campus, and showed our system can display annotations robustly in the large range of outdoor.
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  3. "DESIGN AND EVALUATION OF THE HOME NETWORK SYSTEMS USING THE SERVICE ORIENTED ARCHITECTURE"
    井垣 宏 ( ソフトウェア工学講座 : D3 )
    Hiroshi Igaki ( Software Engineering Lab. : D3 )

    [Abstract]
    In the conventional home network systems (HNS), a powerful centralized server controls all electric home appliances connected to provide value-added integrated services. However, when the number of the appliances increases and the appliances become more sophisticated, the conventional architecture would suffer from problems in superfluous resources, flexibility, scalability and reliability. This paper proposes alternative architecture for HNS, which exploits the service-oriented architecture with Web Services. In the proposed architecture, each appliance is controlled by a Web service in a de-centralized manner. Then, the services autonomously collaborate with each other to achieve the integrated service scenarios. To evaluate the HNS at the design process, we also present four kinds of evaluation metrics: reliability, load, complexity, and coupling. Using these metrics, we conduct a comparative study among the proposed and the previous HNS architectures.

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  4. "A stochastic model for Japanese semantic role labeling"
    ---a proposal and preliminary investigation into 'ni' case ---
    藤田 篤( 自然言語処理学講座 : D3 )
    Atsushi Fujita ( Computational Linguistics Lab. : D3 )

    [Abstract]
    We present a model for identifying the semantic roles in Japanese. The task of semantic role labeling is defined as follows: given an input sentence and a target semantic frame, the model labels grammatical cases of the sentence, such as 'ga (nominative)', 'o (accusative)', 'ni (dative)', with either abstract semantic roles such as AGENT or PATIENT. In Japanese, although some relationships between grammatical cases and their semantic roles have been hypothesized from the linguistic point of view, they have not been justified by a large-scale experiment. We therefore propose a corpus-based robust model for Japanese semantic role labeling, incorporating such hypotheses of linguistics. This presentation presents the proposed model and the result of a preliminary investigation into 'ni' case.

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  5. "Delay Testing Using Partial Scan Technique"
    岩垣 剛 ( コンピューター設計学講座 : D3 )
    Tsuyoshi Iwagaki ( Computer Design and Test Lab. : D3 )

    [Abstract]
    VLSI testing is an essential technology to realize dependable ubiquitous systems because VLSI circuits are basic components of ubiquitous devices. In VLSI testing, full scan design is widely adopted as a design for testability (DFT) approach to reduce the complexity of testing today's VLSI circuits. However, this design approach imposes high area and performance penalties. In order to alleviate these penalties, partial scan design has been proposed as a viable DFT approach. For the stuck-at fault model, which is a conventional fault model, partial scan technique is well studied by many researchers. However, for the delay fault model, which is used for testing high-speed VLSI circuits, it is still not highly considered. We are now investigating a method of delay testing using partial scan technique. In this talk, we survey some existing approaches to test delay faults in full scan circuits, and discuss our research objective and research plan for delay testing using partial scan technique.
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  6. "Stable and Low-Distortion Algorithm for Blind Source Separation Based on Multistage ICA"
    西川 剛樹 ( 音情報処理学講座 : D3 )
    Tsuyoki Nishikawa ( Speech and Acoustic Processing Lab. : D3 )

    [Abstract]
    We newly propose a stable algorithm for blind source separation combining multistage ICA (MSICA) and linear prediction. The MSICA is in which frequency-domain ICA (FDICA) for a rough separation is followed by time-domain ICA (TDICA) to remove residual crosstalk. For speech signals, we must use TDICA with a nonholonomic constraint to avoid the distortion effect from the holonomic constraint. However, the stability cannot be guaranteed in the nonholonomic case. To solve the problem, the linear predictors estimated from the roughly separated signals by FDICA are inserted before the holonomic TDICA as a prewhitening processing, and the dewhitening is performed after TDICA. The stability of the proposed algorithm can be guaranteed by the holonomic constraint, and the pre/dewhitening processing prevents the distortion.
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NAIST Graduate School of Information Science 21st Century COE Program