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  • Two-Dimensional Discrete Orthogonal Transforms by Means of Two-Dimensional LMS Adaptive Algorithms

    Tokunbo OGUNFUNMI  Michael AU  

     
    LETTER-Digital Signal Processing

      Vol:
    E78-A No:9
      Page(s):
    1247-1252

    This paper establishes a general relation between the two-dimensional Least Mean Square (2-D LMS) algorithm and 2-D discrete orthogonal transforms. It is shown that the 2-D LMS algorithm can be used to compute the forward as well as the inverse 2-D orthogonal transforms in general for any input by suitable choice of the adaptation speed. Simulations are presented to verify the general relationship results.

  • Three-Dimensional MMIC and Its Application: An Ultra-Wideband Miniature Balun

    Ichihiko TOYODA  Makoto HIRANO  Tsuneo TOKUMITSU  

     
    PAPER

      Vol:
    E78-C No:8
      Page(s):
    919-924

    A new three-dimensional MMIC structure and an ultra-wideband miniature MMIC balun are proposed. The MMIC is a combined structure of multilayer MMICs and U-shaped micro-wires. This technology effectively reduces chip size and enhances MMIC performance. The proposed balun is constructed with three narrow conductors located side by side. The U-shaped micro-wire technology is employed to reduce the insertion loss and chip size. 1.51 dB insertion loss over 10 to 30 GHz, and 2 dB and 5 degrees of amplitude and phase balances over 5 to 35 GHz have been obtained. The intrinsic area of the balun is only 450800 µm, about 1/5 to 1/3 the area of recently reported miniaturized MMIC baluns.

  • Parallel Processing Techniques for Multidimensional Sampling Lattice Alteration Based on Overlap-Add and Overlap-Save Methods

    Shogo MURAMATSU  Hitoshi KIYA  

     
    PAPER

      Vol:
    E78-A No:8
      Page(s):
    934-943

    In this paper, we propose two parallel processing methods for multidimensional (MD) sampling lattice alteration. The use of our proposed methods enables us to alter the sampling lattice of a given MD signal sequence in parallel without any redundancy caused by up- and down-sampling, even if the alteration is rational and non-separable. Our proposed methods are provided by extending two conventional block processing techniques for FIR filtering: the overlap-add method and the overlap-save method. In these proposed methods, firstly a given signal sequence is segmented into some blocks, secondly sampling lattice alteration is implemented for each block data individually, and finally the results are fitted together to obtain the output sequence which is identical to the sequence obtained from the direct sampling lattice alteration. Besides, we provide their efficient implementation: the DFT-domain approach, and give some comments on the computational complexity in order to show the effectiveness of our proposed methods.

  • Global Dynamic Behaviour of a Parallel Blower System

    Hideaki OKAZAKI  Hideo NAKANO  Takehiko KAWASE  

     
    PAPER-Nonlinear Problems

      Vol:
    E78-A No:6
      Page(s):
    715-726

    A parallel blower system is quite familiar in hydraulic machine systems and quite often employed in many process industries. It is dynamically dual to the fundamental functional element of digital computer, that is, the flip-flop circuit, which was extensively studied by Moser. Although the global dynamic behaviour of such systems has significant bearing upon system operation, no substantial study reports have hitherto been presented. Extensive research concern has primarily been concentrated upon the local stability of the equilibrium point. In the paper, a piecewise linear model is used to analytically and numerically investigate its manifold global dynamic behaviour. To do this, first the Poincar map is defined as a composition boundary map, each of which is defined as the point transformation from the entry point to the end point of any trajectory on some boundary planes. It was already shown that, in some parameter region, the system exhibits the so-called chaotic states. The chaos generating process is investigated using the above Poincar map and it is shown that the map contains the contracting, stretching and folding operations which, as we often see in many cases particularly in horse shoe map, produce the chaotic states. Considering the one dimensional motions of the orbits by such Poincar map, that is, the stretching and folding operations, a one dimensional approximation of the Poincar map is introduced to more closely and exactly study manifold bifurcation processes and some illustrative bifurcation diagrams in relation to system parameters are presented. Thus it is shown how many types of bifurcations like the Hopf, period doubling, saddle node, and homoclinic bifurcations come to exist in the system.

  • Uniform and Non-uniform Normalization of Vocal Tracts Measured by MRI Across Male, Female and Child Subjects

    Chang-Sheng YANG  Hideki KASUYA  

     
    PAPER

      Vol:
    E78-D No:6
      Page(s):
    732-737

    Three-dimensional vocal tract shapes of a male, a female and a child subjects are measured from magnetic resonance (MR) images during sustained phonation of Japanese vowels /a, i, u, e, o/. Non-uniform dimensional differences in the vocal tract shapes of the subjects are quantitatively measured. Vocal tract area functions of the female and child subjects are normalized to those of the male on the basis of non-uniform and uniform scalings of the vocal tract length and compared with each other. A comparison is also made between the formant frequencies computed from the area functions normalized by the two different scalings. It is suggested by the comparisons that non-uniformity in the vocal tract dimensions is not essential in the normalization of the five Japanese vowels.

  • A New Concept of Network Dimensioning Based on Quality and Profit

    Kimihide MATSUMOTO  Satoshi NOJO  

     
    PAPER

      Vol:
    E78-B No:4
      Page(s):
    546-550

    We propose a new concept of network dimensioning, which is based not only on the grade of service but also on profit. In traditional network dimensioning methodology, the number of circuits on links is designed under a cost-minimization concept with grade of service constraints. Recently, telecommunication markets have become very large and competitive; therefore, we believe that a profit viewpoint is now essential. However, it is difficult to calculate profit in almost all the dimensioning methods currently used, because they mainly employ peak-hour traffic data, while profit depends on all the hourly traffic data which contain both peak and off-peak data. In this paper, we propose using all the hourly traffic data in network dimensioning. From these data and telephone charges for each hour, revenues will be estimated. On the other hand, facility costs will be estimated from the number of circuits. Finally, we can estimate profit from the difference between revenues and facility costs. Focusing on both quality and profits in network dimensioning leads to more advanced quality management and quality control in telecommunications networks than with traditional methodology. This paper outlines a dimensioning method based on profit, and describes its properties, some applications of it, and summarizes further studies.

  • Three-Dimensional Microfabrication of Single-Crystal Silicon by Plasma Etching

    Tomoaki GOTO  Kouji MATSUSHITA  Katsumi HIRONO  

     
    PAPER

      Vol:
    E78-C No:2
      Page(s):
    167-173

    A conventional anode coupled plasma etching process has been developed to etch 300 µm-deep cavities and 600 µm-through holes with nearly vertical sidewalls into single crystal silicon. An optimized SF6/O2 gas mixture results in a nearly vertical etching profile. A silicon wafer was fabricated with a large number of cavities and through holes with less than 1 percent uniformity. It was also experimentally confirmed that this process can be used to etch vertical cavities and through holes in single-crystal silicon with any orientation. This process has the advantage of unlimited etching depth and etching patterns. Advantages in mechanical strength are obtained because a micro-curve is formed at the bottom edge of the cavities. This etching process developed on a conventional plasma etching system was utilized to fabricate a torsional vibrator that consists of single-crystal silicon and Pyrex glass.

  • Stable Light-Bullet Formation in a Kerr Medium: A Route to Multidimensional Solitons in the Femtosecond Regime

    Kazuya HAYATA  Hiroyuki HIGAKI  Masanori KOSHIBA  

     
    PAPER

      Vol:
    E78-C No:1
      Page(s):
    38-42

    Ultrashort pulsed-beam propagation in a Kerr-type bulk medium is studied theoretically through classical and quantum field solutions of a higher-order nonlinear Schrödinger equation, which is valid for transversely localized femtosecond pulses in an anomalous dispersion regime. Quantum-mechanical stability analysis via a Hartree approximation to interacting bosons shows that within a certain range of a parameter the solitary wave could be stabilized even in the three-dimensional transverse space-time. This feature admits of an exotic route to multidimensional solitons.

  • Resonance Characteristics of Circularly Propagating Mode in a Coaxial Dielectric Resonator

    Qing HAN  Yoshinori KOGAMI  Yoshiro TOMABECHI  Kazuhito MATSUMURA  

     
    PAPER

      Vol:
    E77-C No:11
      Page(s):
    1747-1751

    A three-dimensional analysis of Whispering-Gallery modes (W. G. modes) in a coaxial dielectric resonator is proposed and presented. The coaxial dielectric resonator is constructed from a lossy dielectric disk and ring which have diameters of several tens times as large as wavelength. Eigenvalue equations of the W. G. modes are derived rigorously from field expressions and boundary conditions. The resonant frequencies, unloaded Q values and field distributions are calculated numerically from the eigenvalue equations. These calculated results are in good agreement with experimental ones for an X band model. As a result, it is shown that a considerable quantity of modal energy can be confined in a loss-less gap between the disk and ring, and then the unloaded Q value is higher than that of a conventional dielectric disk and ring resonator.

  • Evaluation of the Noise Rejection Performance of Linear Trajectory Filters

    Toshitaka TAGO  Nozomu HAMADA  

     
    LETTER-Digital Image Processing

      Vol:
    E77-A No:10
      Page(s):
    1710-1713

    In the design of 3-D filter detecting Linear Trajectory Signal (LTS), there may be paid little attention to the noise rejective characteristics. In this paper, we treat the noise rejection ability of the filter detecting LTS having margins both in its velocity and direction.

  • 2-D Variable FIR Filters Using 3-D Prototype Filters

    Toshiyuki YOSHIDA  Akinori NISHIHARA  Nobuo FUJII  

     
    LETTER-Parallel/Multidimensional Signal Processing

      Vol:
    E77-A No:9
      Page(s):
    1568-1572

    This paper discusses a new design method for 2-D variable FIR digital filters, which is an extension of our previous work for 1-D case. The method uses a 3-D prototype FIR filter whose cross-sections correspond to the desired characteristics of 2-D variable FIR filters. A 2-D variable-angle FIR fan filter is given as a design example.

  • A Method of 3D Object Reconstruction from a Series of Cross-Sectional Images

    Ee-Taek LEE  Young-Kyu CHOI  Kyu Ho PARK  

     
    PAPER

      Vol:
    E77-D No:9
      Page(s):
    996-1004

    This paper addresses a method for constructing surface representation of 3D structures from a sequence of cross-sectional images. Firstly, we propose cell-boundary representation, which is a generalization of PVP method proposed by Yun and Park, and develop an efficient surface construction algorithm from a cell-boundary. Cell-boundary consists of a set of boundary cells with their 1-voxel configurations, and can compactly describe binary volumetric data. Secondly, to produce external surface from the cell-boundary representation, we define 19 modeling primitives (MP) including volumetric, planar and linear groups. Surface polygons are created from those modeling primitives using a simple table look-up operation. Since a cell-boundary can be obtained using only topological information of neighboring voxels, there is no ambiguity in determining modeling primitives which may arise in PVP method. Since our algorithm has data locality and is very simple to implement, it is very appropriate for parallel processing.

  • Optimal Filtering Algorithm Using Covariance Information in Linear Continuous Distributed Parameter Systems

    Seiichi NAKAMORI  

     
    PAPER-Control and Computing

      Vol:
    E77-A No:6
      Page(s):
    1050-1057

    This paper presents an optimal filtering algorithm using the covariance information in linear continuous distributed parameter systems. It is assumed that the signal is observed with additive white Gaussian noise. The autocovariance function of the signal, the variance of white Gaussian noise, the observed value and the observation matrix are used in the filtering algorithm. Then, the current filter has an advantage that it can be applied to the case where a partial differential equation, which generates the signal process, is unknown.

  • Three-Dimensionally Fully Space Constructible Functions

    Makoto SAKAMOTO  Katsushi INOUE  Itsuo TAKANAMI  

     
    LETTER-Artificial Intelligence and Cognitive Science

      Vol:
    E77-D No:6
      Page(s):
    723-725

    There have been several interesting investigations on the space functions constructed by one-dimensional or two-dimensional Turing machines. On the other hand, as far as we know, there is no investigation about the space functions constructed by three-dimensional Turing machines. In this paper, we investigate about space constructibility by three-dimensional deterministic Turing machines with cubic inputs, and show that the functions log*n and log(k)n, k1, are fully space constructible by these machines.

  • Interpolatory Estimation of Multi-Dimensional Orthogonal Expansions with Stochastic Coefficients

    Takuro KIDA  Somsak SA-NGUANKOTCHAKORN  Kenneth JENKINS  

     
    PAPER-Digital Signal Processing

      Vol:
    E77-A No:5
      Page(s):
    900-916

    Relating to the problem of suppressing the immanent redundancy contained in an image with out vitiating the quality of the resultant approximation, the interpolation of multi-dimensional signal is widely discussed. The minimization of the approximation error is one of the important problems in this field. In this paper, we establish the optimum interpolatory approximation of multi-dimensional orthogonal expansions. The proposed approximation is superior, in some sense, to all the linear and the nonlinear approximations using a wide class of measures of error and the same generalized moments of these signals. Further, in the fields of information processing, we sometimes consider the orthonormal development of an image each coefficient of which represents the principal featurr of the image. The selection of the orthonormal bases becomes important in this problem. The Fisher's criterion is a powerful tool for this class of problems called declustering. In this paper, we will make some remarks to the problem of optimizing the Fisher's criterion under the condition that the quality of the approximation is maintained.

  • A State Space Approach for Distributed Parameter Circuit--Disturbance-Rejection Problem for Infinite-Dimensional Systems--

    Naohisa OTSUKA  Hiroshi INABA  Kazuo TORAICHI  

     
    PAPER

      Vol:
    E77-A No:5
      Page(s):
    778-783

    It is an important problem whether or not we can reject the disturbances from distributed parameter circuit. In order to analyze this problem structurally, it is necessary to investigate the basic equation of distributed parameter circuit in the framework of state space. Since the basic equation has two parameters for time and space, the state value belongs to an infinite-dimensional space. In this paper, the disturbance-rejection problems with incomplete state feedback and/or incomplete state feedback and feedforward for infinite-dimensional systems are studied in the framework of geometric approach. And under certain assumptions, necessary and/or sufficient conditions for these problems to be solvable are proved.

  • Recent Free-Space Photonic Switches

    Masayasu YAMAGUCHI  Ken-ichi YUKIMATSU  

     
    INVITED PAPER

      Vol:
    E77-B No:2
      Page(s):
    128-138

    This paper briefly reviews recent studies on free-space photonic switches, and discusses classifications, applications and technical issues to be solved. The free-space photonic switch is a switch that uses light beam interconnections based on free-space optics instead of guided-wave optics. A feature of the free-space switch is its high-density three-dimensional structure that enables compact large-scale switches to be created. In this paper, the free-space switches are classified by their various attributes such as logical network configuration, path-establishment method, number of physical stages, signal-waveform transmission form, interconnection optics and so on. The logical network configuration (topological geometry or topology) is strongly related to the advantages of the free-space switches over the guided-wave switches. The path-establishment method (path-shifting/branching-and-gating) and the number of physical stages (single-stage/multistage) are related to physical switching characteristics. Signal-waveform transmission form (analog/digital) is related to switch application. Interconnection optics (imaging system/micro-beam system) is related to the density and volume of the switching fabric. Examples of the free-space switches (single-stage, analog multistage, digital multistage and photonic ATM switches) are described. Possible applications for analog switches are subscriber-line concentrators, inter-module connectors, and switching networks for parallel or distributed computer systems. Those for digital switches include multistage space-division switches in time-division circuit-switching or packet switching systems (including asynchronous transfer mode [ATM] switching system) for both communications switching systems and parallel/distributed computer systems. Technical issues of the free-space switches (system, device, assembly technique) must be solved before creating practical systems. In particular, the assembly technique is a key issue of the free-space switches.

  • A Numerical Simulation of the Effects of the Actual Lip Geometry on Acoustic Fields by a Three-Dimensional FEM

    Chengxiang LU  Takayoshi NAKAI  Hisayoshi SUZUKI  

     
    PAPER-Speech

      Vol:
    E77-A No:2
      Page(s):
    422-428

    This paper describes an implementation of the finite element method to examine the effects of actual lip shape on the sound radiation. A three-dimensional finite element approach by Galerkin method was used. The accuracy of the calculation of finite element method for the sound radiation was tested by comparing it with the exact solutions for a circular piston radiator on an infinite baffle. Using a set of finite element models of the vocal tract, we calculated the responses to a pure tone input and the sound fields over the frequency range of 100 Hz-7 kHz. The transfer functions are examined in detail for vowels /a/ and /i/ when the shape of the actual lips is simplified as a planeradiation surface. The effects of lip shape on the distribution of sound pressures are also shown in both the vocal tract and the surrounding space of the mouth opening.

  • Evaluation of Two-Dimensional Transient Enhanced Diffusion of Phosphorus during Shallow Junction Formation

    Hisako SATO  Katsumi TSUNENO  Hiroo MASUDA  

     
    PAPER-Process Simulation

      Vol:
    E77-C No:2
      Page(s):
    106-111

    Recently, high-dose implantation and low temperature annealing have become one of the key techniques in shallow junction formation. To fabricate shallow junction in quarter-micron CMOS VLSIs, it is well known being important to evaluate the transient enhanced diffusion (TED) of implanted dopants at low temperature furnace annealing, which is caused by the damages of implantation. We have newly studied the TED phenomena by a compact empirical method. This approach has merits of simplicity and better physical intuition, because we can use only minimal parameters to describe the TED phenomena. The other purpose of this work is to evaluate two-dimensional transient enhanced diffusion focusing on phosphorus implant and furnace annealing. Firstly, we defined effective diffusivity of the TED and determined extraction procedure of the model parameters. Number of the TED model parameters is minimized to two, which describe effective enhanced diffusivity and its activation energy. The parameters have been extracted from SIMS profile data obtained from samples which range 1013-31015 cm-2 and 850-950 for phosphorus implanted dose and annealing temperature, respectively. Simulation results with the extracted transient enhanced diffusion parameters show good agreements well with the SIMS data within 2% RMS-error. Critical doses for phosphorus enhanced diffusion have been determined in 950 annealing condition. No transient enhanced diffusion is observed at 950 under the implant dose of 11013 cm-2. Also the transient enhanced diffusivity is leveled off over the dose of 11014 cm-2. It is seen that the critical dose in TED phenomena might be temperature dependent to a certain extent. We have also verified that two-dimensional effect of the TED phenomena experimentally. Two-dimensional phosphorus n- layer is chosen to verify the simulation. It was concluded that the TED has isotropic nature in phosphorus n- diffusion formation.

  • A System for 3D Simulation of Complex Si and Heterostructure Devices

    Paolo CONTI  Masaaki TOMIZAWA  Akira YOSHII  

     
    PAPER-Numerics

      Vol:
    E77-C No:2
      Page(s):
    220-226

    A software package has been developed for simulating complex silicon and heterostructure devices in 3D. Device geometries are input with a mouse-driven geometric modeler, thus simplifying the definition of complex 3D shapes. Single components of the device are assembled through boolean operations. Tetrahedra are used for grid generation, since any plane-faced geometry can be tessellated with tetrahedra, and point densities can be adapted locally. The use of a novel octree-like data structure leads to oriented grids where desirable. Bad angles that prevent the convergence of the control volume integration scheme are eliminated mostly through topological transformations, thus avoiding the insertion of many redundant grid points. The discretized drift-diffusion equations are solved with an iterative method, using either a decoupled (or Gummel) scheme, or a fully coupled Newton scheme. Alternatively, generated grids can be submitted to a Laplace solver in order to calculate wire capacitances and resistances. Several examples of results illustrate the flexibility and effectiveness of this approach.

301-320hit(350hit)