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[Keyword] fusion(253hit)

221-240hit(253hit)

  • An Isolated Word Speech Recognition Based on Fusion of Visual and Auditory Information Usisng 30-frame/s and 24-bit Color Image

    Akio OGIHARA  Shinobu ASAO  

     
    PAPER

      Vol:
    E80-A No:8
      Page(s):
    1417-1422

    In the field of speech recognition, many researchers have proposed speech recognition methods using auditory information like acoustic signal or visual information like shape and motion of lips. Auditory information has valid features for speech recognition, but it is difficult to accomplish speech recognition in noisy environment. On the other side, visual information has advantage to accomplish speech recognition in noisy environment, but it is difficult to extract effective features for speech recognition. Thus, in case of using either auditory information or visual information, it is difficult to accomplish speech recognition perfectly. In this paper, we propose a method to fuse auditory information and visual information in order to realize more accurate speech recognition. The proposed method consists of two processes: (1) two probabilities for auditory information and visual information are calculated by HMM, (2) these probabilities are fused by using linear combination. We have performed speech recognition experiments of isolated words, whose auditory information (22.05kHz sampling, 8-bit quantization) and visual information (30-frame/s sampling, 24-bit quantization) are captured with multi-media personal computer, and have confirmed the validity of the proposed method.

  • Detecting Lung Cancer Symptoms with Analogic CNN Algorithms Based on a Constrained Diffusion Template

    Satoshi HIRAKAWA  Csaba REKECZKY  Yoshifumi NISHIO  Akio USHIDA  Tamas ROSKA  Junji UENO  Ishtiaq KASEM  Hiromu NISHITANI  

     
    LETTER-Nonlinear Problems

      Vol:
    E80-A No:7
      Page(s):
    1340-1344

    In this article, a new type of diffusion template and an analogic CNN algorithm using this diffusion template for detecting some lung cancer symptoms in X-ray films are proposed. The performance of the diffusion template is investigated and our CNN algorithm is verified to detect some key lung cancer symptoms, successfully.

  • Model for Thermal Noise in Semiconductor Bipolar Transistors at Low-Current Operation as Multidimensional Diffusion Stochastic Process

    Yevgeny V.MAMONTOV  Magnus WILLANDER  

     
    PAPER-Electronic Circuits

      Vol:
    E80-C No:7
      Page(s):
    1025-1042

    This work presents a further development of the approach to modelling thermal (i.e. carrier-velocity-fluctuation) noise in semiconductor devices proposed in papers by the present authors. The basic idea of the approach is to apply classical theory of Ito's stochastic differential equations (SDEs) and stochastic diffusion processes to describe noise in devices and circuits. This innovative combination enables to form consistent mathematical basis of the noise research and involve a great variety of results and methods of the well-known mathematical theory in device/circuit design. The above combination also makes our approach completely different, on the one hand, from standard engineering formulae which are not associated with any consistent mathematical modelling and, on the other hand, from the treatments in theoretical physics which are not aimed at device/circuit models and design. (Both these directions are discussed in more detail in Sect. 1). The present work considers the bipolar transistor compact model derived in Ref. [2] according to theory of Ito's SDEs and stochastic diffusion processes (including celebrated Kolmogorov's equations). It is shown that the compact model is transformed into the Ito SDE system. An iterative method to determine noisy currents as entries of the stationary stochastic process corresponding to the above Ito system is proposed.

  • Structure and Mechanism Estimation of an Articulated Object by Motion Observation

    Takeshi NAGASAKI  Toshio KAWASHIMA  Yoshinao AOKI  

     
    PAPER-Image Processing,Computer Graphics and Pattern Recognition

      Vol:
    E80-D No:7
      Page(s):
    733-741

    In this paper, we propose a method to construct structure models of articulated objects from multiple local observations of their motion using state transition analysis of local geometric constraints. The object model is constructed by a bottom-up approach with three levels. Each level groups sensor data with a constraint among local features observed by the sensor, and constructs the local model. If the sensor data in current model conflict, the model is reconstructed. In each level, the first level estimates a local geometric feature from the local sensor data (eg. edge, feature point) The second level estimates a rigid body from the local geometric feature. The third level estimates an object from the rigid bodies. In the third level, the constraint between rigid bodies is estimated by transition states, which are motions between rigid bodies. This approach is implemented on a blackboard system.

  • A Novel Chirped Fiber Bragg Grating Utilizing Thermal Diffusion of Core Dopant

    Satoshi OKUDE  Tetsuya SAKAI  Masaaki SUDOH  Akira WADA  Ryozo YAMAUCHI  

     
    PAPER

      Vol:
    E80-B No:4
      Page(s):
    551-556

    A novel technique is proposed to fabricate a chirped fiber Bragg grating utilizing thermal diffusion of core dopant. The chirped grating is written with a uniform period by using UV exposure technique in the fiber whose effective index of the guided mode varies along its length. Thermal diffusion of the core dopant it employed to realize this change of the effective index. Through the thermal diffusion process, the effective index of the fiber decreases from its initial value. When the grating is written in the diffused core region, its reflection wavelength becomes shorter than that in the non-diffused region. The continuous change of effective index is required for making a chirped grating. The fiber is heated by a non-uniform heat source. When the uniform grating is written in this region, the reflection wavelength smoothly changes along the fiber length although the grating period is constant. By optimizing the fiber parameters to realize a highly chirped grating, we have obtained a typical one whose bandwidth is 14.1 nm at half maximum and maximum rejection in transmission is 29 dB. Additionally, the proposed method has an advantage to control the chirp profile with high mechanical reliability.

  • 1200 Dots-Per-Inch Light Emitting Diode Array Fabricated by Solid-Phase Zinc Diffusion

    Mitsuhiko OGIHARA  Takatoku SHIMIZU  Masumi TANINAKA  Yukio NAKAMURA  Ichimatsu ABIKO  

     
    PAPER-Semiconductor Materials and Devices

      Vol:
    E80-C No:3
      Page(s):
    489-497

    We developed a 1200 dots-per-inch light emitting diode array (1200 dpi LED array) chip using a GaAs0.8 P0.2 epitaxial substrate for the first time. One LED array chip consists of 256 LEDs. In general, LED arrays are fabricated by vapor-phase zinc diffusion. From the viewpoint that shallow junctions should be formed to fabricate a very high-density LED array, solid-phase diffusion seems to be more suitable. We fabricated the LED array using selectively-masked solid-phase zinc diffusion, and the diffusion depth was controlled at 1 µm. The diffusion depth was uniform under the diffusion window. The ratio of the length of lateral diffusion to the diffusion depth was about 1.7. These features imply that Zn diffusion was well controlled. In the Zn diffusion, the carrier concentration in the Zn diffusion region was high enough and the sheet resistance of the diffusion region with a diffusion depth of 1 µm was low enough to obtain a sufficient level of emitted light power. The results of performance tests showed that the characteristics of the LED array chip are satisfactory for application in optical printer print heads, because of the array's highly-resolved near-field pattern characteristic, ample emitted light power, low emitted-light-power deviation, and long life.

  • Necessary and Sufficient Condition for Liveness of Asymmetric Choice Petri Nets

    Tadashi MATSUMOTO  Yasuhiko TSURUTA  

     
    PAPER

      Vol:
    E80-A No:3
      Page(s):
    521-533

    Petri net is a graphical and mathematical tool for modelling, analysis, verification, and evaluation of discrete event systems. Liveness is one of the most important problems of Petri net analysis. This is concerned with a capability for firing of transitions and can be interpreted as a problem to decide whether the system under consideration is always able to reach a stationary behavior, or to decide whether the system is free from any redundant elements. An asymmetric choice (AC) net is a superclass of useful subclasses such as EFCs, FCs, SMs, and MGs, where SMs admit no synchronization, MGs admit no conflicts, FCs as well as EFCs admit no confusion, and ACs allow asymmetric confusion but disallow symmetric confusion. It is known that an AC net N is live iff it is place-live, but this is not the "initial-marking-based" condition and place-liveness is in general hard to test. For the initial-marking-based liveness for AC nets, it is only known that an AC net N is live if (but not only if) every deadlock in N contains a marked structural trap.

  • Speech Recognition Based on Fusion of Visual and Auditory Information Using Full-Framse Color Image

    Satoru IGAWA  Akio OGIHARA  Akira SHINTANI  Shinobu TAKAMATSU  

     
    LETTER

      Vol:
    E79-A No:11
      Page(s):
    1836-1840

    We propose a method to fuse auditory information and visual information for accurate speech recognition. This method fuses two kinds of information by using Iinear combination after calculating two kinds of probabilities by HMM for each word. In addition, we use full-frame color image as visual information in order to improve the accuracy of the proposed speech recognition system. We have performed experiments comparing the proposed method with the method using either auditory information or visual information, and confirmed the validity of the proposed method.

  • Feature Extraction of Postage Stamps Using an Iterative Approach of CNN

    Jun KISHIDA  Csaba REKECZKY  Yoshifumi NISHIO  Akio USHIDA  

     
    LETTER-Neural Networks

      Vol:
    E79-A No:10
      Page(s):
    1741-1746

    In this article, a new analogic CNN algorithm to extract features of postage stamps in gray-scale images Is introduced. The Gradient Controlled Diffusion method plays an important role in the approach. In our algorithm, it is used for smoothing and separating Arabic figures drawn with a color which is similar to the background color. We extract Arabic figures in postage stamps by combining Gradient Controlled Diffusion with nearest neighbor linear CNN template and logic operations. Applying the feature extraction algorithm to different test images it has been verified that it is also effective in complex segmentation problems

  • An Isolated Word Speech Recognition Using Fusion of Auditory and Visual Information

    Akira SHINTANI  Akiko OGIHARA  Naoshi DOI  Shinobu TAKAMATSU  

     
    PAPER

      Vol:
    E79-A No:6
      Page(s):
    777-783

    We propose a speech recognition method using fusion of auditory and visual information for accurate speech recognition. Since we use both auditory information and visual information, we can perform speech recognition more accurately in comparison with the case of either auditory information or visual information. After processing each information by HMM, they are fused by linear combination with weight coefficient. We performed experiments and confirmed the validity of the proposed method.

  • High-Resolution Penumbral Imaging of 14-MeV Neutrons

    Yen-Wei CHEN  Noriaki MIYANAGA  Minoru UNEMOTO  Masanobu YAMANAKA  Tatsuhiko YAMANAKA  Sadao NAKAI  Tetsuo IGUCHI  Masaharu NAKAZAWA  Toshiyuki IIDA  Shinichi TAMURA  

     
    PAPER-Opto-Electronics

      Vol:
    E78-C No:12
      Page(s):
    1787-1792

    We have developed a neutron imaging system based on the penumbral imaging technique. The system consists of a penumbral aperture and a sensitive neutron detector. The aperture was made from a thick (6 cm) tungsten block with a toroidal taper. It can effectively block 14-MeV neutrons and provide a satisfactory sharp, isoplanatic (space-invariant) point spread function (PSF). A two-dimensional scintillator array, which is coupled with a gated two-stage image intensifier system and a CCD camera, was used as a sensitive neutron detector. It can record the neutron image with high sensitivity and high signal-to-noise ratio. The reconstruction was performed with a Wiener filter. The spatial resolution of the reconstructed neutron image was estimated to be 31 µm by computer simulation. Experimental demonstration has been achieved by imaging 14-MeV deuterium-tritium neutrons emitted from a laser-imploded target.

  • A Study on Mouth Shape Features Suitable for HMM Speech Recognition Using Fusion of Visual and Auditory Information

    Naoshi DOI  Akira SHINTANI  Yasuhisa HAYASHI  Akio OGIHARA  Shinobu TAKAMATSU  

     
    LETTER

      Vol:
    E78-A No:11
      Page(s):
    1548-1552

    Recently, some speech recognition methods using fusion of visual and auditory information have been researched. In this paper, a study on the mouth shape image suitable for fusion of visual and auditory information has been described. Features of mouth shape which are extracted from gray level image and binary image are adopted, and speech recognition using linear combination method has been performed. From results of speech recognition, the studies on the mouth shape features which are effective in fusion of visual and auditory information have been performed. And the effectiveness of using two kinds of mouth shape features also has been confirmed.

  • SAM: a New Statistical Multiplexer that Regenerates CBR Connections for ATM Networks

    Francis PITCHO  Naoaki YAMANAKA  

     
    LETTER-Switching and Communication Processing

      Vol:
    E78-B No:9
      Page(s):
    1330-1332

    This letter presents SAM, a multiplexer for ATM's circuit emulation services that can precisely control the cell clumping at the connection-level. Compared with a FIFO (First In First Out) multiplexer, it also improves the connection-level diffusion and CDV (Cell Delay Variation) performance. SAM can therefore significantly increase the number of connections accepted by CAC (Call Admission Control) procedures in the subsequent multiplexer.

  • Growth, Design and Performance of InP-Based Heterostructure Bipolar Transistors

    Kenji KURISHIMA  Hiroki NAKAJIMA  Shoji YAMAHATA  Takashi KOBAYASHI  Yutaka MATSUOKA  

     
    INVITED PAPER

      Vol:
    E78-C No:9
      Page(s):
    1171-1181

    This paper discusses crystal-growth and device-design issues associated with the development of high-performance InP/InGaAs heretostructure bipolar transistors (HBTs). It is shown that a highly Si-doped n+-subcollector in the HBT structure causes anomalous Zn redistribution during metalorganic vapor phase epitaxial (MOVPE) growth. A thermodynamical model of and a useful solution to this big problem are presented. A novel hybrid structure consisting of an abrupt emitter-base heterojunction and a compositionally-graded base is shown to enhance nonequilibrium base transport and thereby increase current gain and cutoff frequency fT. A double-heterostructure bipolar transistor (DHBT) with a step-graded InGaAsP collector can improve collector breakdown behavior without any speed penalty. We also elucidate the effect of emitter size shrinkage on high-frequency performance. Maximum oscillation frequency fmax in excess of 250 GHz is reported.

  • A Study on Speaker Adaptation for Mandarin Syllable Recognition with Minimum Error Discriminative Training

    Chih-Heng LIN  Chien-Hsing WU  Pao-Chung CHANG  

     
    PAPER

      Vol:
    E78-D No:6
      Page(s):
    712-718

    This paper investigates a different method of speaker adaptation for Mandarin syllable recognition. Based on the minimum classification error (MCE) criterion, we use the generalized probabilistic decent (GPD) algorithm to adjust interatively the parameters of the hidden Markov models (HMM). The experiments on the multi-speaker Mandarin syllable database of Telecommunication Laboratories (T.L.) yield the following results: 1) Efficient speaker adaptation can be achieved through discriminative training using the MCE criterion and the GPD algorithm. 2) The computations required can be reduced through the use of the confusion sets in Mandarin base syllables. 3) For the discriminative training, the adjustment on the mean values of the Gaussian mixtures has the most prominent effect on speaker adaptation. 4) The discriminative training approach can be used to enhance the speaker adaptation capability of the maximum a posteriori (MAP) approach.

  • Nonlocal Impact Ionization Model and Its Application to Substrate Current Simulation of n-MOSFET's

    Ken-ichiro SONODA  Mitsuru YAMAJI  Kenji TANIGUCHI  Chihiro HAMAGUCHI  Tatsuya KUNIKIYO  

     
    PAPER

      Vol:
    E78-C No:3
      Page(s):
    274-280

    We propose a nonlocal impact ionization model applicable for the drain region where electric field increases exponentially. It is expressed as a function of an electric field and a characteristic length which is determined by a thickness of gate oxide and a source/drain junction depth. An analytical substrate current model for n-MOSFET is also derived from the new nonlocal impact ionization model. The model well explains the reason why the theoretical characteristic length differs from empirical expressions used in a pseudo two-dimensional model for MOSFET's. The nonlocal impact ionization model implemented in a device simulator demonstrates that the new model can predict substrate current correctly in the framework of drift-diffusion model.

  • "Deterministic Diffusion" in a Neural Network Model

    Hideo MATSUDA  Akihiko UCHIYAMA  

     
    LETTER

      Vol:
    E77-A No:11
      Page(s):
    1879-1881

    This paper describes that a neural network, which consists of neurons with piecewise–linear sigmoid characteristics, is able to approximate any piecewise–linear map with origin symmetry. The neural network can generate "deterministic diffusion" originating from its diffusive trajectory.

  • Speech Recognition Using HMM Based on Fusion of Visual and Auditory Information

    Akira SHINTANI  Akio OGIHARA  Yoshikazu YAMAGUCHI  Yasuhisa HAYASHI  Kunio FUKUNAGA  

     
    LETTER

      Vol:
    E77-A No:11
      Page(s):
    1875-1878

    We propose two methods to fuse auditory information and visual information for accurate sppech recognition. The first method fuses two kinds of information by using linear combination after calculating two kinds of probabilities by HMM for each word. The second method fuses two kinds of information by using the histogram which expresses the correlation of them. We have performed experiments comparing the proposed methods with the conventional method and confirmed the validity of the proposed methods.

  • Numerical Studies of Pattern Formation and Lyapunov Exponents in Chaotic Reaction–Diffusion Systems

    Hiroyuki NAGASHIMA  

     
    PAPER-Chaos and Related Topics

      Vol:
    E77-A No:11
      Page(s):
    1806-1810

    Numerical studies of reaction–diffusion systems which consist of chaotic oscillators are carried out. The Rössler oscillators are used, which are arranged two–dimensionally and coupled by diffusion. Pacemakers where the average periods of the oscillators are artificially changed are set to produce target patterns. It is found that target patterns emerge from pacemakers and grow up as if they were in a regular oscillatory medium. The wavelength of the pattern can be varied and controlled by changing the parameters (size and frequency) of the pacemaker. The behavior of the coupled system depends on the size of the system and the strength of the pacemaker. When the system size is large, the Poincar return maps show that the behavior of the coupled system is not simple and the orbit falls into a high–dimensional attractor, while for a small system the attractor is rather simple and a one–dimensional map is obtained. Moreover, for appropriate strength of pacemakers and for certain sizes of the systems the oscillations become periodic. It is also found that the largest and local Lyapunov exponents of the system are positive and these values are uniformly distributed over the pattern. The values of the exponents are smaller than that of the uncoupled Rössler oscillator; this is due to the fact that the diffusion reduces the exponents and modifies the form of the attractor. We conclude that the large scale patterns can stably exist in the chaotic medium.

  • Theory of Chemical Waveguides

    Kazuya HAYATA  Masanori KOSHIBA  

     
    LETTER-Electromagnetic Theory

      Vol:
    E77-C No:10
      Page(s):
    1706-1709

    We predict that chemical waves can propagate as a guided mode in a reaction-diffusion system that consists of two regions with different wave speeds. In comparison with electromagnetic waveguides, unique features of the guided chemical waves can be seen in their dispersion characteristics. Conditions for supporting lowest-loss guided waves are discussed.

221-240hit(253hit)