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[Keyword] TE(21534hit)

12441-12460hit(21534hit)

  • A Practical Approach for Efficiently Extracting Interconnect Capacitances with Floating Dummy Fills

    Atsushi KUROKAWA  Toshiki KANAMOTO  Akira KASEBE  Yasuaki INOUE  Hiroo MASUDA  

     
    PAPER-VLSI Design Technology and CAD

      Vol:
    E88-A No:11
      Page(s):
    3180-3187

    We present a practical method of dealing with the influences of floating dummy metal fills, which are inserted to assist planarization by chemical-mechanical polishing (CMP) process, in extracting interconnect capacitances for system-on-chip (SoC) designs. The method is based on reducing the thicknesses of dummy metal layers according to electrical field theory. We also clarify the influences of dummy metal fills on the parasitic capacitance, signal delay, and crosstalk noise. Moreover, we address that interlayer dummy metal fills have more significant influences than intralayer ones in terms of the impact on coupling capacitances. When dummy metal fills are ignored, the error of capacitance extraction can be more than 30%, whereas the error of the proposed method is less than about 10% for many practical geometries. We also demonstrate, by comparison with capacitance results measured for a 90-nm test chip, that the error of the proposed method is less than 8%.

  • Information-Spectrum Characterization of Multiple-Access Channels with Correlated Sources

    Ken-ichi IWATA  Yasutada OOHAMA  

     
    PAPER-Information Theory

      Vol:
    E88-A No:11
      Page(s):
    3196-3202

    In this paper, Information-Spectrum characterization is derived for the reliable transmission of general correlated sources over the general multiple-access channels. We consider the necessary and sufficient conditions for the transmission of general correlated sources over the general multiple-access channels by using Information-Spectrum methods which are introduced by Han and Verdu.

  • Adaptive Colorimetric Characterization of Camera for the Variation of White Balance

    Eun-Su KIM  Sung-Hak LEE  Soo-Wook JANG  Kyu-Ik SOHNG  

     
    LETTER

      Vol:
    E88-C No:11
      Page(s):
    2086-2089

    The RGB signals generated by different cameras are not equal for the same scene. Therefore, cameras are characterized based on a CIE standard colorimetric observer. One method of deriving a colorimetric characterization matrix between camera RGB output signals and CIE XYZ tristimulus values is least squares polynomial modeling. Yet, this involves tedious experiments to obtain a camera transfer matrix under various white balance points for the same camera. Accordingly, the current paper proposes a new method for obtaining camera transfer matrices under different white balances using a 33 camera transfer matrix under a specific white balance point.

  • Interference Analysis from Impulse Radio UWB Systems Using Simple Signal Models

    Yasuo SUZUKI  Ichihiko TOYODA  Masahiro UMEHIRA  

     
    PAPER

      Vol:
    E88-A No:11
      Page(s):
    3092-3099

    The interference imposed on conventional narrow-band systems by impulse radio UWB (IR-UWB) signals is examined by simulations. The Dirac delta function is employed to model the IR-UWB signal to reduce simulation costs. The simulation results show that the statistical characteristics of this interference deviate from Gaussian noise when the frequency band of the narrow-band system includes a half multiple of the data symbol rate of the IR-UWB system. In the case of pulse-position-modulation UWB signals and biorthogonal-coded bipolar-modulation UWB signals, the performance degradation of the narrow-band system depends on the number of pulse positions and the number of orthogonal codes, respectively.

  • Fast J-Unitary Array Form of the Hyper H Filter

    Kiyoshi NISHIYAMA  

     
    PAPER-Digital Signal Processing

      Vol:
    E88-A No:11
      Page(s):
    3143-3150

    In our previous work, the hyper H∞ filter is developed for tracking of unknown time-varying systems. Additionally, a fast algorithm, called the fast H∞ filter, of the hyper H∞ filter is derived on condition that the observation matrix has a shifting property. This algorithm has a computational complexity of O(N) where N is the dimension of the state vector. However, there still remains a possibility of deriving alternative forms of the hyper H∞ filter. In this work, a fast J-unitary form of the hyper H∞ filter is derived, providing a new H∞ fast algorithm, called the J-fast H∞ filter. The J-fast H∞ filter possesses a computational complexity of O(N), and the resulting algorithm is very amenable to parallel processing. The validity and performance of the derived algorithm are confirmed by computer simulations.

  • Convergence Analysis of Adaptive Filters Using Normalized Sign-Sign Algorithm

    Shin'ichi KOIKE  

     
    LETTER-Digital Signal Processing

      Vol:
    E88-A No:11
      Page(s):
    3218-3224

    This letter develops convergence analysis of normalized sign-sign algorithm (NSSA) for FIR-type adaptive filters, based on an assumption that filter tap weights are Gaussian distributed. We derive a set of difference equations for theoretically calculating transient behavior of filter convergence, when the filter input is a White & Gaussian process. For a colored Gaussian input and a large number of tap weights, approximate difference equations are also proposed. Experiment with simulations and theoretical calculations of filter convergence demonstrates good agreement between simulations and theory, proving the validity of the analysis.

  • Characteristics of a Chromatic Dispersion Measurement Method Using the Bidirectional Modulation of Optical Intensity Modulator

    Keum-Soo JEON  Young-Seok WANG  Sang-Chul MOON  Jae-Kyung PAN  

     
    LETTER-Measurement Technology

      Vol:
    E88-A No:11
      Page(s):
    3260-3263

    We had recently measured a chromatic dispersion of optical fiber and a time delay of chirped fiber grating based on a bidirectional modulation of an optical intensity modulator. In this paper, we analyze characteristics of the chromatic dispersion measurement method using a bidirectional modulation of an optical intensity modulator, and give a detailed explanation about the selection of measurement setup parameters to achieve an accurate measurement. We also propose a modified measurement system to decrease relative intensity noise caused by the bidirectional transmission through a device under test.

  • Efficient Design of Low-Complexity Bit-Parallel Systolic Hankel Multipliers to Implement Multiplication in Normal and Dual Bases of GF (2m)

    Chiou-Yng LEE  Che-Wun CHIOU  

     
    PAPER-Circuit Theory

      Vol:
    E88-A No:11
      Page(s):
    3169-3179

    Normal and dual bases are two popular representation bases for elements in GF(2m). In general, each distinct representation basis has its associated different hardware architecture. In this paper, we will present a unified systolic array multiplication architecture for both normal and dual bases, such a unified multiplication architecture is termed a Hankel multiplier. The Hankel multiplier has lower space complexity while compared with other existing normal basis multipliers and dual basis multipliers.

  • Detection System of Clustered Microcalcifications on CR Mammogram

    Hideya TAKEO  Kazuo SHIMURA  Takashi IMAMURA  Akinobu SHIMIZU  Hidefumi KOBATAKE  

     
    PAPER-Biological Engineering

      Vol:
    E88-D No:11
      Page(s):
    2591-2602

    CR (Computed Radiography) is characterized by high sensitivity and wide dynamic range. Moreover, it has the advantage of being able to transfer exposed images directly to a computer-aided detection (CAD) system which is not possible using conventional film digitizer systems. This paper proposes a high-performance clustered microcalcification detection system for CR mammography. Before detecting and classifying candidate regions, the system preprocesses images with a normalization step to take into account various imaging conditions and to enhance microcalcifications with weak contrast. Large-scale experiments using images taken under various imaging conditions at seven hospitals were performed. According to analysis of the experimental results, the proposed system displays high performance. In particular, at a true positive detection rate of 97.1%, the false positive clusters average is only 0.4 per image. The introduction of geometrical features of each microcalcification for identifying true microcalcifications contributed to the performance improvement. One of the aims of this study was to develop a system for practical use. The results indicate that the proposed system is promising.

  • Speech Synthesis with Various Emotional Expressions and Speaking Styles by Style Interpolation and Morphing

    Makoto TACHIBANA  Junichi YAMAGISHI  Takashi MASUKO  Takao KOBAYASHI  

     
    PAPER

      Vol:
    E88-D No:11
      Page(s):
    2484-2491

    This paper describes an approach to generating speech with emotional expressivity and speaking style variability. The approach is based on a speaking style and emotional expression modeling technique for HMM-based speech synthesis. We first model several representative styles, each of which is a speaking style and/or an emotional expression, in an HMM-based speech synthesis framework. Then, to generate synthetic speech with an intermediate style from representative ones, we synthesize speech from a model obtained by interpolating representative style models using a model interpolation technique. We assess the style interpolation technique with subjective evaluation tests using four representative styles, i.e., neutral, joyful, sad, and rough in read speech and synthesized speech from models obtained by interpolating models for all combinations of two styles. The results show that speech synthesized from the interpolated model has a style in between the two representative ones. Moreover, we can control the degree of expressivity for speaking styles or emotions in synthesized speech by changing the interpolation ratio in interpolation between neutral and other representative styles. We also show that we can achieve style morphing in speech synthesis, namely, changing style smoothly from one representative style to another by gradually changing the interpolation ratio.

  • Producing Effective Shot Transitions in CG Contents Based on a Cognitive Model of User Involvement

    Masashi OKAMOTO  Yukiko I. NAKANO  Kazunori OKAMOTO  Ken'ichi MATSUMURA  Toyoaki NISHIDA  

     
    PAPER

      Vol:
    E88-D No:11
      Page(s):
    2523-2532

    In virtue of great progress in computer graphics technologies, CG movies have been getting popular. However, cinematography techniques, which contribute to improving the contents' comprehensibility, need to be learned from professional experiences, and not easily acquired by non-professional people. This paper focuses on film cutting as one of the most important cinematography techniques in conversational scenes, and presents a system that automatically generates shot transitions to improve comprehensibility of CG contents. First, we propose a cognitive model of User Involvement serving as constraints on selecting shot transitions. Then, to examine the validity of the model, we analyze shot transitions in TV programs, and based on the analysis, we implement a CG contents creation system. Results of our preliminary evaluation experiment show the effectiveness of the proposed method, specifically in enhancing contents' comprehensibility.

  • Quality of Service Management Scheme for Adaptive Service in Wireless/Mobile Multimedia Cellular Networks

    Sung-Hwan JUNG  Jung-Wan HONG  Chang-Hoon LIE  

     
    PAPER-Wireless Communication Technologies

      Vol:
    E88-B No:11
      Page(s):
    4317-4327

    An adaptive service framework is expected to support real-time multimedia services in wirless/mobile cellular networks with various classes of traffic and diverse bandwidth requirements. Quality of service (QoS) provisioning in an adaptive framework is another challenging consideration, such as quantifying the level of bandwidth degradation of an ongoing calls and guaranteeing stable QoS levels. Considering both the period and the depth of degradation, the degradation area ratio (DAR) represents the average ratio of a call's degradation and is one of the meaningful measures for adaptive service in call level analysis. In this paper, analytical models for estimating the DAR and finding the optimal control parameters are presented in multi-class traffic call management situations. In complete partitioning capacity based threshold-type call admission control (CAC), a one-dimensional Markov chain with an absorbing state is proposed for estimating the DAR in each traffic class. We formulate a two-leveled optimization problem minimizing the total blocking probabilities subject to QoS requirements and present the procedures required in finding the optimal capacities and threshold values by using modified dynamic programming. In complete sharing capacity based threshold-type CAC, the multidimensional Markov model is approximately reduced to a one-dimensional model in order to reduce complexity and hence calculation time. The reduced model is compared with multidimensional Markov model in numerical examples. The optimization problem is formulated minimizing the total blocking probabilities subject to QoS requirements and the optimal threshold parameters are found by using a genetic algorithm. Performance of two adopted admission policies in adaptive framework situations is illustrated by numerical results.

  • High-Luminance EL Devices Using Zn2Si1-XGeXO4:Mn Thin Films Prepared by Combinatorial Deposition by r.f. Magnetron Sputtering with Subdivided Powder Targets

    Toshihiro MIYATA  Yu MOCHIZUKI  Tadatsugu MINAMI  

     
    INVITED PAPER

      Vol:
    E88-C No:11
      Page(s):
    2065-2069

    A new technique incorporating combinatorial deposition to develop thin-film phosphors by r.f. magnetron sputtering is demonstrated using subdivided powder targets. In comparison with development using conventional r.f. magnetron sputtering, the atomic ratios of Si and Ge as well as the Mn content in Zn2Si1-XGeXO4:Mn thin film phosphors could be more efficiently optimized in order to obtain the highest intensity in electroluminescent and photoluminescent emissions. High luminances of 11800 and 1536 cd/m2 were obtained in Zn2Si0.6Ge0.4O4:Mn thin-film electroluminescent devices fabricated under optimized conditions and driven at 1 kHz and 60 Hz, respectively.

  • Interactive Object Recognition System for a Helper Robot Using Photometric Invariance

    Md. Altab HOSSAIN  Rahmadi KURNIA  Akio NAKAMURA  Yoshinori KUNO  

     
    PAPER

      Vol:
    E88-D No:11
      Page(s):
    2500-2508

    We are developing a helper robot that carries out tasks ordered by the user through speech. The robot needs a vision system to recognize the objects appearing in the orders. It is, however, difficult to realize vision systems that can work in various conditions. Thus, we have proposed to use the human user's assistance through speech. When the vision system cannot achieve a task, the robot makes a speech to the user so that the natural response by the user can give helpful information for its vision system. Our previous system assumes that it can segment images without failure. However, if there are occluded objects and/or objects composed of multicolor parts, segmentation failures cannot be avoided. This paper presents an extended system that tries to recover from segmentation failures using photometric invariance. If the system is not sure about segmentation results, the system asks the user by appropriate expressions depending on the invariant values. Experimental results show the usefulness of the system.

  • Integration between Scheduling and Design of Batch Systems Based on Petri Net Models

    Takashi ITO  Susumu HASHIZUME  Tomoyuki YAJIMA  Katsuaki ONOGI  

     
    PAPER

      Vol:
    E88-A No:11
      Page(s):
    2989-2998

    A batch process is a discontinuous and concurrent process which is suitable for multi-product, small-sized production. The distinctive feature of a batch process is that various decision making processes, such as scheduling, design, operation, etc. are strongly connected with each other. Interaction among these processes is necessary to dynamically and flexibly cope with a variety of unplanned events. This paper aims at presenting a batch scheduling technique based on Petri net models and showing the possibilities of integration between scheduling and design of batch processes. For this purpose, it first views the behavior of a batch operating system as a discrete event system and presents a Petri net model to be used for scheduling, design and operation. It next formulates batch scheduling problems based on Petri net partial languages, proposes their solution technique and last discusses the integration between scheduling and design of batch systems.

  • Multiuser Detection for MC-CDMA System Using an RQP Approach

    Xianmin WANG  Zhiwei MAO  

     
    LETTER-Wireless Communication Technologies

      Vol:
    E88-B No:11
      Page(s):
    4394-4397

    A recursive quadratic programming (RQP) approach is proposed for multiuser detection in multicarrier code-division multiple-access (MC-CDMA) systems. In this approach, the combinatorial problem associated with the optimal maximum likelihood (ML) detection is relaxed to a quadratic programming (QP) problem first and then a recursive approach is developed to improve the detection performance. Computer simulations are presented which demonstrate that the detector developed based on the proposed approach offers close-to-optimal symbol-error rate (SER) performance which outperforms several existing suboptimal detectors.

  • Modeling and Measurement of Mode-Conversion and Frequency Dependent Loss in High-Speed Differential Interconnections on Multilayer PCB

    Seungyong BAEK  Jingook KIM  Joungho KIM  

     
    PAPER-Microwaves, Millimeter-Waves

      Vol:
    E88-C No:10
      Page(s):
    1992-2000

    We propose an accurate and efficient model of having an unbalanced differential line structure, where mode-conversion and frequency dependent loss effects are considered in above the GHz frequency range. To extract model parameters of the proposed unbalanced differential line model, we measured s-parameters of test patterns using a 2-port VNA and defined a new type of mixed-mode s-parameter. The model parameters were obtained and are described for various types of the unbalanced differential line structures. Finally, the validity of the proposed model and the model parameters were successfully confirmed by a series of time-domain measurements and a lattice diagram analysis.

  • Optimal Tracking Design for Hybrid Uncertain Input-Delay Systems under State and Control Constraints via Evolutionary Programming Approach

    Yu-Pin CHANG  

     
    PAPER-Algorithm Theory

      Vol:
    E88-D No:10
      Page(s):
    2317-2328

    A novel digital redesign methodology based on evolutionary programming (EP) is introduced to find the 'best' digital controller for optimal tracking design of hybrid uncertain multi-input/ multi-output (MIMO) input-delay systems with constraints on states and controls. To deal with these multivariable concurrent specifications and system restrictions, instead of conventional interval methods, the proposed global optimization scheme is able to practically implement optimal digital controller for constrained uncertain hybrid systems with input time delay. Further, an illustrative example is included to demonstrate the efficiency of the proposed method.

  • Experimental Analysis of Guess-and-Determine Attacks on Clock-Controlled Stream Ciphers

    Shinsaku KIYOMOTO  Toshiaki TANAKA  Kouichi SAKURAI  

     
    PAPER-Cryptography and Information Security

      Vol:
    E88-A No:10
      Page(s):
    2778-2791

    Guess-and-Determine (GD) attacks have recently been proposed for the effective analysis of word-oriented stream ciphers. This paper discusses GD attacks on clock-controlled stream ciphers, which use irregular clocking for a non-linear function. The main focus is the analysis of irregular clocking for GD attacks. We propose GD attacks on a typical clock-controlled stream cipher AA5, and calculate the process complexity of our proposed GD attacks. In the attacks, we assume that the clocking of linear feedback shift registers (LFSRs) is truly random. An important consideration affecting the practicality of these attacks is the question of whether these assumptions are realistic. Because in practice, the clocking is determined by the internal states. We implement miniature ciphers to evaluate the proposed attacks, and show that they are applicable. We also apply the GD attacks to other clock controlled stream ciphers and compare them. Finally, we discuss some properties of GD attacks on clock-controlled stream ciphers and the effectiveness of the clock controllers. Our research results contain information that are useful in the design of clock-controlled stream ciphers.

  • Separable 2D Lifting Using Discrete-Time Cellular Neural Networks for Lossless Image Coding

    Hisashi AOMORI  Kohei KAWAKAMI  Tsuyoshi OTAKE  Nobuaki TAKAHASHI  Masayuki YAMAUCHI  Mamoru TANAKA  

     
    PAPER

      Vol:
    E88-A No:10
      Page(s):
    2607-2614

    The lifting scheme is an efficient and flexible method for the construction of linear and nonlinear wavelet transforms. In this paper, a novel lossless image coding technique based on the lifting scheme using discrete-time cellular neural networks (DT-CNNs) is proposed. In our proposed method, the image is interpolated by using the nonlinear interpolative dynamics of DT-CNN, and since the output function of DT-CNN works as a multi-level quantization function, our method composes the integer lifting scheme for lossless image coding. Moreover, the nonlinear interpolative dynamics by A-template is used effectively compared with conventional CNN image coding methods using only B-template. The experimental results show a better coding performance compared with the conventional lifting methods using linear filters.

12441-12460hit(21534hit)