Steel Science Portal

Transactions of the Institute of Systems, Control and Information Engineers
New Arrival Alert : OFF

You can use this feature after you logged into the site.
Please click the button below.

Log in / Sign up
ONLINE ISSN: 2185-811X
PRINT ISSN: 1342-5668

Transactions of the Institute of Systems, Control and Information Engineers Vol. 1 (1988), No. 2

  • On the Limit Cycles with a Period Not Equal to Sampling Period Multiplied by Integer, in the Sector-type Nonlinear Sampled-data System

    Hayato OHNISHI, Setsuo SAGARA

    pp. 45-52

    Bookmark

    You can use this feature after you logged into the site.
    Please click the button below.

    Log in / Sign Up

    DOI:10.5687/iscie.1.45

    Abstract

    This paper extends the concept of the discrete describing function proposed previously for the analysis of sector type nonlinear sampled data control systems. The previously defined functions were only applicable to the signals which have sub-harmonics of sampling frequencies. We remove the restriction on frequencies and make it possible to apply to an arbitrary frequency. All frequencies less than a half of the sampling frequency are divided into many groups.
    For frequencies that belong to the same group, the evaluation of the discrete describing function provides the same region on the complex-plane. Practically, it is enough to consider a few shapes of these regions. Drawing the inverse Nyquist diagram of linear part of the system on the same complex-plane, limit cycles are predicted by the well-known. graphical method.
    To clarify the description, a few examples are given. The simulation results show that our proposed method is useful for predicting limit cycles which have a period not equal to the sampling period multiplied by an integer.

  • Design of Servomechanisms Using Sliding Mode and Quasi-Sliding Mode

    Hiromitsu HIKITA, Hiroshi KUBO, Tadao NARITA

    pp. 53-60

    Bookmark

    You can use this feature after you logged into the site.
    Please click the button below.

    Log in / Sign Up

    DOI:10.5687/iscie.1.53

    Abstract

    A method for designing a servomechanism using sliding mode is considered. This servomechanism of which the input-output relation is given by a transfer function is insensitive with respect to disturbances, parameter variations, and nonlinearity. The structure of this servomechanism satisfies the internal model principle. A servo-mechanism is also given which is obtained by quasi-sliding mode based on a continuous control law to avoid chattering. The properties of errors due to the application of the continuous control law are further investigated. It is shown that the design of the servomechanisms can easily extended to that of multivariable servomechanisms. An example is given in order to illustrate the efficiency of the proposed design method.

  • A Design of a Discrete-Time Adaptive Repetitive Control System

    Mitsuaki ISHITOBI, Zenta IWAI, Keiichi HIROMOTO, Mitsushi HINO

    pp. 61-67

    Bookmark

    You can use this feature after you logged into the site.
    Please click the button below.

    Log in / Sign Up

    DOI:10.5687/iscie.1.61

    Abstract

    This paper presents an adaptive repetitive control scheme for discrete-time linear systems. The boundedness of input and output signals, and the convergence of the control error are proved.
    A discrete-time repetitive control structure with a specified convergence property for known parameters plants was considered by Shinnaka. However, when plant parameters are not known, the desired convergence speed is not accomplished. Since the algorithm with adaptive mechanism proposed here, is able to achieve the specified convergence rate of the control error for unknown parameters systems, the convergence speed is improved. Simulation examples are shown to confirm the effectiveness of the design scheme presented in this paper.

  • Identification of a Linear System with Switching Parameters by the EM Algorithm

    Masahiro TANAKA, Tohru KATAYAMA

    pp. 68-76

    Bookmark

    You can use this feature after you logged into the site.
    Please click the button below.

    Log in / Sign Up

    DOI:10.5687/iscie.1.68

    Abstract

    We consider the identification problem for a linear system when the variances of the system and/or the observation noises take on two unknown values. It is assumed that the system and observation noises can be represented in terms of Bernoulli sequences and two random variables with specified but unknown variances. We propose an algorithm to simultaneously estimate the unknown variances and the switching parameters by applying the EM (expectation-maximization) algorithm, avoiding non-linear optimizations that arise in the Maximum Likelihood (ML) and the Maximum A Posteriori (MAP) estimations. Several numerical examples are given to illustrate the effectiveness of the present algorithm.
  • © 1988 THE INSTITUTE OF SYSTEMS, CONTROL AND INFORMATION ENGINEERS (ISCIE)

Article Access Ranking

20 Sep. (Last 30 Days)

  1. Formation and Evolution of Inclusions in High Chromium Steel ISIJ International Vol.61(2021), No.9
  2. Perspective toward Long-term Global Goal for Carbon Dioxide Mitigation in Steel Industry Tetsu-to-Hagané Vol.105(2019), No.6
  3. Effect of Heating Rate on Carbothermic Reduction and Melting Behavior of Iron Ore-Coal Composite Pellets ISIJ International Advance Publication
  4. Preface to the Special Issue on “Recent Progress in Inclusion/ Precipitate Engineering” ISIJ International Vol.61(2021), No.9
  5. Evaluation of Interfacial Energy between Molten Fe and Fe-18%Cr-9%Ni Alloy and Non-Metallic Inclusion-Type Oxides ISIJ International Vol.61(2021), No.9
  6. Production and Technology of Iron and Steel in Japan during 2020 ISIJ International Vol.61(2021), No.6
  7. Modeling of Wall Shear Stress Induced Inclusion Transport and Removal in Multi-Strand Tundish ISIJ International Vol.61(2021), No.9
  8. Three-dimensional Quantitative Evaluation of the Lamellar Curvature in Pearlitic Steel Based on an Orientation Analysis of Cementite ISIJ International Advance Publication
  9. Analysis of Air-Mist Cooling Effect for Coil in the Electromagnetic Induction Controlled Automated Steel Teeming System ISIJ International Vol.61(2021), No.9
  10. Simultaneous Analysis of Soluble and Insoluble Oxygen Contents in Steel Specimens Using Inert Gas Fusion Infrared Absorptiometry ISIJ International Vol.61(2021), No.9

Search Phrase Ranking

20 Sep. (Last 30 Days)

  1. blast furnace
  2. inconel 600
  3. blast furnace productivity
  4. miyamoto goro
  5. nozzle clogging
  6. b2o3 mold flux
  7. blue carbon
  8. investigation of arc behavior and temperature distribution corresponding to electrode and phase configurations in a multiphase ac arc
  9. ohno
  10. sei kimura