All issues
Volume 21, Issue 10
Displaying 1-21 of 21 articles from this issue
- |<
- <
- 1
- >
- >|
-
Akira SANO, Koichi HASHIMOTO1985 Volume 21 Issue 10 Pages 1007-1012
Published: October 30, 1985
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSA new technique is proposed to estimate frequencies and amplitudes of sinusoids embedded in background signals with unknown colored spectrum. In such cases Pisarenko's harmomic retrieval (PHR) method can give no unbiased estimates. The present approach can eliminate the biases by whitening the colored noise in observed data which is modelled as an autoregressive (AR) process, and adopting the PHR method to the filtered signal. The parameters of the whitening FIR filter are determined so as to minimize a specified criterion whose minimum value is attained when the parameters agree with those of the AR process. The criterion also plays an important role of deciding the number of noise-corrupted sinusoids. The paper also gives a method of obtaining the gradient vector of the criterion with respect to the filter parameters, which is needed to perform the conjugate gradient method. The validity of the present method is examined in numerical examples.View full abstractDownload PDF (807K) -
Relief of Unmodeled Dynamics Effects via Variable LimiterShinji SHINNAKA, Takashi SUZUKI1985 Volume 21 Issue 10 Pages 1013-1020
Published: October 30, 1985
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSThis paper presents a method for designing discrete-time adaptive pole placers applicable to nonminimum-phase plants of unknown order and unkown dead-time.
An adaptive pole placer has attracted attention as an adaptive controller applicable to nonminimum-phase plants. However most of the conventinal design methods for the placer require the exact order of the plant of unknown characteristics and resitrict their applications to existing plants. A conceivable approach to the plant of unknown order will be the one based on a reduced order model to it, in consideration of unmodeled dynamics effects. In such approach the indirect method could remain as a potential one since the placers designed via the direct method are very sensitive to unmodeled dynamics and haadly parform stably.
The method to be presented here is, an indirect method based on reduced order model, which is characterized by the employments, to overcome the effects of unmodeled dynamics, both of a new parameter adjustment algorithm having attractive properties and of a variable limiter being able to change its limiting level adaptively. The placers designed by the method are stable in global sense and exhibit reasonable performance.View full abstractDownload PDF (998K) -
Seizo FUJII, Naoki MIZUNO1985 Volume 21 Issue 10 Pages 1021-1028
Published: October 30, 1985
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSThis paper presents the design method of discrete time adaptive control system based on pole placement method for linear time invariant plant with unknown deterministic disturbances.
The disturbances which are treated here are described by the polynomial function of time and/or the output of the stable autonomous system with known order and unknown coefficients.
In this paper, first, the structures of the controller which decouples the disturbances from the plant output, in the cases where the parameters of the plant and characteristic polynomials of the disturbances are known, are discussed. Next, the procedure of constructing the adaptive control system, where the dynamics of the plant and disturbances are unknown, is described.
Finally, the result of computer simulation of the adaptive control applied to a second order non-minimum phase plant with sinusoidal disturbance is included to illustrate the effectiveness of the proposed method.View full abstractDownload PDF (1076K) -
Tetsuo SHIOTSUKI, Shigeyasu KAWAJI, Kohji TANAKA1985 Volume 21 Issue 10 Pages 1029-1035
Published: October 30, 1985
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSIn this paper, we propose a method of model reduction for SISO continuous systems via block-pulse functions.
A set of block-pulse functions is well known as an orthonormal system. But it is not complete in L2-space. In this paper, we clarify that it has a property which corresponds to the completeness, when the space is restricted to bounded, piecewise-continuous functions. And it is pointed out that multiple-integration in functional space is reduced to simple algebraic operations on block-pulse expansion coefficients.
Based on these facts, a method of model reduction is proposed. In first step, block-pulse expansion of input is calculated. And in second step, that of output is calculated. In third step, the parameters of reduced model are calculated via least square algorithm.
The main characteristics of this method are (1) simplicity of algorithm, (2) time-domain approximation, and (3) applicability of any polynomial type input.View full abstractDownload PDF (702K) -
Yasuaki NAKAMURA, Shigeru ABE, Shouichi TAKEDA1985 Volume 21 Issue 10 Pages 1036-1042
Published: October 30, 1985
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSThe design of industrial sequence control systems, such as power plants, is often carried out by the modification of an old design. The paper describes a new method to verify whether the functional change caused by the modification may influence the unmodified portion or not.
Assume that a portion A of an original system is modified to A', and the remaining unmodified portion is B. The portion A and the modified portion A' include a controller part and controlled devices.
Both A and A' are converted into timed petri nets: TPN (A) and TRN (A'). TPN (A) and TPN (A') have inputs I which are signals from B and outputs O which are signals to B. As B is affected by the outputs O, the change of outputs O is examined.
In order to check the difference between A and A', TPN (A) and TPN (A') are converted into automata with the reachability tree. In this conversion, only stable markings, in which no transition is ‘firable’ if the inputs (I) never change, are selected as the states of the automata. The inputs, the state transitions and the outputs of the automata are obtained from the inputs (I), the change of markings and the outputs (O) of TPN (A) and TPN (A'), respectively.
The paper shows that the functional change is easy to verify by comparing the automata's output functions of the old design and the new one. Besides, the automata are used to generate test inputs to check the functional change.View full abstractDownload PDF (897K) -
Masahiro OOBA, Norihisa KOMODA, Kuniaki MATSUMOTO1985 Volume 21 Issue 10 Pages 1043-1050
Published: October 30, 1985
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSTraditionally, control software for the discrete systems such as FMS and coal-handling system has been developed using general purpose language based on the heuristic algorithm obtained through experience. However, development and modification of the control software consume time and man-hours because of uncomprehensive experession. In order to resolve the problem, a new control method, named the Rule Based Control method, has emerged.
In this method, as the control logics are described by the IF-THEN rules as data, maintainability and comprehensiveness of control software are extremely improved. However, this new method has following three problems: (1) the suitable domain for the rule description is not clear, (2) procedure of the rule development for multi-objective and multi-constraint control problem is not established, (3) the quantitative metrics for the rule expressions do not exist. This paper concerns with these problems.
First we define the control problem of the discrete system as the problem selecting alternatives such as works and resources to satisfy many constraint conditions and objective conditions. For specification of this type of control problems, IF-THEN rules are suitable for expressing these conditions. Next, the Halstead's metrics, which is one of the metrics for the property of general purpose languages, is enhanced to deal with rule expression based on the mechanism of the inference system.
The proposed method described above is successfully applied to the control rules development of a coal-handling system. The effectiveness of the procedure is shown by comparing the rule solution with Pareto optimal solutions. Furthermore, the enhanced metrics are validated through the comparison between rule expression and Fortran program.View full abstractDownload PDF (1199K) -
Qunfei ZHAO, Yoshitaka TOGARI, Hideo GOTO1985 Volume 21 Issue 10 Pages 1051-1057
Published: October 30, 1985
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSIn this paper, a procedure is proposed to decompose large scale systems with quadratic performance index into a number of interconnected subsystems controlled by a decentralized multilevel scheme. And using it, the interactions of local controllers are dealt with in the same way as the inherent interconnections among states without the assumption that the original system have been (translated into) an input-decentralized one. Furthermore a specific way is shown to determine higher level control operation so as to ensure the local autonomy and improve the overall performance as much as possible. Finally, a numerical example is given to illustrate these results.View full abstractDownload PDF (846K) -
Yasutaka TAMURA, Hiro YAMASAKI1985 Volume 21 Issue 10 Pages 1058-1064
Published: October 30, 1985
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSMultiple transmitters and receivers enable ultrasound Doppler velocimetry to resolve the position and velocity vectors of multiple targets.
In this paper, the capability of the system is analized theoreticaly using generalized Ambiguity Function.
Ambiguity and variace bound analysis indicates the desired conditions of array configuration and signal waveforms. The desired transmitted signals are uncorrelated waveforms of no Range-Doppler coupling, and the array configurations depend on the moments and SN ratios of signals.
The performance of the range and angular velocity estimation is measured as Cramér-Rao bounds of estimates for the simple case of 1-D array which satisfies the conditions. The measure is written in terms of array size, moments of transmitted signal waveforms, and SN ratios.View full abstractDownload PDF (913K) -
Ichizo ITOH, Tetsuo ANDOH, Shin-ichi OHKI1985 Volume 21 Issue 10 Pages 1065-1071
Published: October 30, 1985
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSVortex shedding frequency generated by bluff body is proportional to flow velocity even in three dimentional flow.
By means of this hydrodynamic phenomenon-so-called karman vortices, vortex flowmeter went on sale approximately ten years ago, but generally not were used as industrial floweter.
In recent years, however, applications of vortex flowmeters are increasing widely.
That is because characteristic advantages of this flowmeter are acknowledged generally, and new approach to sensing vortex frequency makes this flowmeter possible to operate under severe flow conditions.
This paper describes “stress sensing system”-piezo electric element builtin vortex shedder senses internal stress in bluff body which results from the lift caused by vortex shedding. And measurements involving high-temperature and high-pressure gas, steam and liquid flow are all possible.View full abstractDownload PDF (2071K) -
Yoshio KANO, Shinya HASEBE, Toshiki SHIMAMURA, Toraji TAWARA, Fusakazu ...1985 Volume 21 Issue 10 Pages 1072-1079
Published: October 30, 1985
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSIt is very important to measure growth of plant for analyzing its physiology, growth mechanism and producing it efficienty in agriculture.
There are many reports about measurment of a stem diameter, a plant height, a leaf area, water transportation in a stem and so on. There are quite few measurments about root which spreads under the ground as same as a stem and leves. Because it is very difficult to detect the root system in the ground. They are trying to detect it in sight by the way of “Glass-faced Profile Wall Method”.
Then, it is tried to measure the root system in the ground by the electric method here. At first, the new electiric conductivity meter is developed by using the four electrodes method. The four hurdle-type electrodes are developed for measurment of the root system as it does not exert influence on the seepage flow of water in the soil. The conductivity meter with this hurdle-type electrodes and the developed electric circuit has good characteristics; (1) the wide conductivity range, (2) the linear output in proportion to the conductivity, (3) high accuracy in reappearance, stability, ageing, influence of other tings and mutual interference between two electrodes.
Using this conductivity meter, the growth of root is tried to measure. The four hurdle-type electrodes are beried in the soil and the agar for the comperison and the observation in sight. As the root absorbs water from the soil or agar, water content changes near the root. When the root comes near the electrodes, water content near the electrodes changes and conductivity also decreases. It appears when the root reaches 5mm apart from the electrodes. The growth of root can be measured by detecting the change of conductivity using this meter.View full abstractDownload PDF (1790K) -
Haruaki OTSUKI, Hiromu HIRAI, Yo IKEBE1985 Volume 21 Issue 10 Pages 1080-1085
Published: October 30, 1985
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSIn this paper, a simple structured feedback compensation scheme for a DC electric servo system to keep the response characteristics unchanged regardless of the load variation is proposed.
In a DC servo motor, the angular velocity is determined by the output torque and the armature voltage. The influence of the output torque which depends on the external load must be eliminated to make the system load insensitive. Several feedback compensation methods have been developed to eliminate the influence. As a result of the compensation, angular velocity of a DC servo motor is determined only by the error signal. Consequently, the closed-loop servo system is made load insensitive. Joint utilization of the proposed compensation and acceleration and velocity feedback compensation can offer extended freedom for design of a load insensitive servo system. Applicable region of the proposed schme can be specified through stability considerations. The compensation scheme has been verified to be effective by the static response and the dynamic response in the time domain and the frequency domain through experiments.View full abstractDownload PDF (819K) -
Noboru NAKATANI, Atsunori UEHARA, Tomoharu YAMADA1985 Volume 21 Issue 10 Pages 1086-1091
Published: October 30, 1985
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSThis paper describes the signal processor by the use of an acoustooptic light deflector for processing of LDV signals in real time and with high speed. The position sensitive device using the lateral photo-effect of a semiconductor is investigated for real time measurement of the displacement of a beam spot with large intensity variation. The frequency response of the processor is 100kHz and the frequency resolution, 5kHz. As the processor is open loop system, it can process LDV signals in wide frequency range and with high speed compared with a conventional frequency tracker. Using the flow around a circular cylinder, it is demonstrated that this signal processor can be used for continuous and discontinuous LDV signals and is a powerful tool for highly instationary flow.View full abstractDownload PDF (1740K) -
Yoshito OHTA, Hajime MAEDA, Shinzo KODAMA, Shoichi TAKEDA1985 Volume 21 Issue 10 Pages 1092-1097
Published: October 30, 1985
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSThis paper considers a fault diagnosis problem of linear systems and derives a fault diagnosis algorithm.
The motivation of this paper is as follows. Fault diagnosis methods are divided into two main classes, analytical method (which uses mathematical models of the system), and konw ledge-based method. This paper considers the problem after analytical method, because it will offer an efficient computerized automatic diagnosis technique if some difficulties which it has so far are settled. These difficulties are:
1) it requires highly nonlinear calculation if we exploit, for example, parameter identification method; and
2) it lacks a computer-oriented algorithm. To cope with these difficulties the algorithm presented here has two marked features:
1) it is based on linear algebraic consideration; and
2) graphical techniques are adoptable in part by introducing the system representation graph.
The former serves a simple calculation method, and the latter serves to introduce graphical algorithm techniques.
This paper considers the problem in the following manner. Firstly, it is shown that the observation vector lies in the subspace corresponding to the fault when the system is malfunctioning. Then this fact is used to distinguish faults under a certain condition which is made clear in this paper. Based upon these considerations, a fault diagnosis algorithm is proposed, and it is proved that the algorithm is justifiable. Finally, the algorithm is applied to a linear steady system to show
1) that a part of algorithm is replaced by a graphical algorithm which explains the relation between the fault diagnosibility and the system structure; and
2) that the quantities and the calculations in the algorithm are clarified through the concrete representation of the algorithm.View full abstractDownload PDF (901K) -
Hidetoshi WAKAMATSU, Toshiyuki KITAMORI1985 Volume 21 Issue 10 Pages 1098-1104
Published: October 30, 1985
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSA method of controlling nonlinear systems using Volterra series is applied to the control of respiration. This method is based on the description of a respiratory system by discrete-time Volterra series. The control system is synthesized by the connection of an input-observer and a dynamical compensator, which are used respectively, for the reproduction of an input-function hard to be measured (metabolic rate change) and for the generation of a controlling input (air ventilation rate change). It provides an accurate and quick output control of alveolar CO2-concentration by the manipulation of an air ventilation rate, eliminating the effect of any undesirable irregular metabolic rate change on the output.View full abstractDownload PDF (1046K) -
Morio TAKAHAMA, Takashi KIMURA, Ryozaburo TAGAWA1985 Volume 21 Issue 10 Pages 1105-1112
Published: October 30, 1985
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSIn this paper, we propose a new design method of the low-sensitive flight control system that has constant gain controller and constant closed loop transfer function when aircraft dynamics changes in wide range.
This method is based on Tagawa's new design method using utmost compensator that has the following advantage: the designer can specify the transfer functions of reference to controlled variable and disturbance to controlled variable, independently.
The design procedure consists of the following steps:
(1) Define the degree of freedom of gains of the utmost compensator when the transfer function of reference to controlled variable is fixed.
(2) Assume the class of the change of controlled object dynamics and verify the validity of the assumption.
(3) Transform the change of controlled object dynamics to a equivalent disturbance, and minimize the transfer function of the disturbance to controlled variable.View full abstractDownload PDF (828K) -
Billet Conditioning Line ControlIsao TSUSHIMA, Tsutomu TASHIRO, Norihisa KOMODA, Kazushi BABA, Syuuich ...1985 Volume 21 Issue 10 Pages 1113-1120
Published: October 30, 1985
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSIn factory automation systems, it is strongly desired to provide highly flexible control software because of frequent system modification. However, short term development and modification of control software is difficult for traditional control software which is developed by using procedural general purpose programming languages.
Recently, konwledge engineering methods which can describe control logics directly and in non-procedural manner have been applied to many fields. However, few applications have been put to practical use. Furthermore, very little is reported about these implementation.
We have applied the knowledge engineering method to real time control of billet conditioning line in steel works.
The paper presented rule based control system applied to billet conditioning line and its evaluation. First, the software configuration in which high flexibility, high response and easy interface to plant were considered, is presented. Next, the practical method for checking consistency of control logic is presented. Finally, evaluation results about the application are presented. Based on real data, it is presented that control software is developed step by step and easily modified. As the results, control software development man power were reduced to 1/3 compared with traditional methods. Additionally, useful know-how such as the ratio of inference time for response time (about 20%), software construction method of rule based control system with which control logics can be modified only by data modification are presented.View full abstractDownload PDF (1146K) -
Hiroyuki TAMURA, Shiro HIKITA1985 Volume 21 Issue 10 Pages 1121-1123
Published: October 30, 1985
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSDownload PDF (308K) -
Toshio KOMATSUZAKI1985 Volume 21 Issue 10 Pages 1124-1126
Published: October 30, 1985
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSDownload PDF (294K) -
Mitsuaki ISHITOBI, Norihiko ADACHI, Kazuo MANO, Seiji INOUE, Hidekatsu ...1985 Volume 21 Issue 10 Pages 1127-1129
Published: October 30, 1985
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSDownload PDF (425K) -
Yoji TAKEDA, Masaaki YAMASHITA, Takao HIRASA, Keiichi FUCHI1985 Volume 21 Issue 10 Pages 1130-1132
Published: October 30, 1985
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSDownload PDF (308K) -
1985 Volume 21 Issue 10 Pages 1135
Published: 1985
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSDownload PDF (96K)
- |<
- <
- 1
- >
- >|