巻号一覧
25 巻, 8 号
選択された号の論文の17件中1～17を表示しています
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章 勍寧, 佐藤 拓宋1989 年 25 巻 8 号 p. 829-835
発行日: 1989/08/30
公開日: 2009/03/27
ジャーナル フリーIn the previous letter a new method for noninvasive measurement of 2-D velocity field of steady flows has been proposed and the effectiveness was confirmed by computer simulation. It uses multiple line detectors and high order correlation analysis.
In this paper, a concrete system which uses 4.5MHz ultrasonic beams as the line detectors is shown.
Experiments were carried out for the following three types of flow fields in a water tank; 1) straight streams, 2) curved streams and 3) continuous wide flow. The stream was generated by passing water through a thin tube. The experimental results showed clearly the usefulness of the proposed method.
The relations between the patterns in the high order correlation function spaces and the characteristics of the flow are also shown.抄録全体を表示PDF形式でダウンロード (861K) -
新井 優, 澤田 重明, 櫻井 弘久1989 年 25 巻 8 号 p. 836-840
発行日: 1989/08/30
公開日: 2009/03/27
ジャーナル フリーA sealed glass cell was developed for the precise realization of the triple point of gallium.
The triple point of gallium, one of the most important fixed points for platinum resistance thermometry at room temperatures, has been realized by plastic cells. It is because of the increase in volume of gallium on solidification, and the plastic cell is not suitable for a leakage-free triple-point cell. Those problems are solved by adopting a vacuum glass cell with a teflon container.
The triple-point temperatures of gallium realized by the developed cell are found to be constant for about two months within ±0.04mK. The average temperatures measured by two standard platinum resistance thermometers are 29.77367°C and 29.77361°C by the representation of the International Practical Temperature Scale of 1968. The differences of the triple-point temperatures between the present sealed glass cell and the conventional plastic cell are also discussed.抄録全体を表示PDF形式でダウンロード (647K) -
中谷 登, 山田 朝治, 阪部 俊也1989 年 25 巻 8 号 p. 841-846
発行日: 1989/08/30
公開日: 2009/03/27
ジャーナル フリーOptical fiber heterodyne interferometry with the following desirable features has been investigated to measure displacement of an object: it is extremely sensitive, noncontacting and has a linear relation between detector output and displacement. However, other systems have suffered from external disturbance because the reference light arm has a different path from the signal light arm. This paper describes the optical fiber heterodyne interferometer probe free from external disturbance in the optical paths of two fibers used to measure small displacement of an object. The external disturbance is excluded by differentiating the phases of the beat signals from two fibers, which include equal phase fluctuation in the fibers due to the disturbance. To improve the S/N ratio, we coated dielectric reflecting mirrors onto the output ends of the fibers. This probe sensor makes it posible to measure a small displacement of 0.1nm.抄録全体を表示PDF形式でダウンロード (809K) -
西口 憲一, 土屋 和雄1989 年 25 巻 8 号 p. 847-853
発行日: 1989/08/30
公開日: 2009/03/27
ジャーナル フリーThe problem of reduced-order adaptive estimation for singularly perturbed systems, which are two-time scale continuous-time stochastic systems, is considered in the framework of nonlinear filtering. It is shown that in some case the parameter estimate by a reduced-order adaptive estimator designed for a reduced-order model has a bias even in the limit when fast variables are infinitely fast. This is in contrast with the linear estimation for a singularly perturbed system where the difference between state estimates by a reduced-order Kalman filter and a full-order Kalman filter vanishes in the limit when fast variables are infinitely fast. It is then shown that the bias of the parameter estimate is attributable to the problem of stochastic integrals, i.e., a part of the Itô integrals appeared in the nonlinear filter equations is actually calculated as Stratonovich-like integrals when the reduced-order adaptive estimator is used. Numerical examples are given to illustrate the bias of the parameter estimate. Finally, conditions are given under which the bias of parameter estimate vanishes.抄録全体を表示PDF形式でダウンロード (841K) -
相原 伸一1989 年 25 巻 8 号 p. 854-859
発行日: 1989/08/30
公開日: 2009/03/27
ジャーナル フリーThe infinite dimensional parameter estimation for stochastic heat diffusion equation is considered using the method of sieves. The consistency property is also studied for a long run data.抄録全体を表示PDF形式でダウンロード (636K) -
佐藤 光男, 竹田 宏, 岩崎 知巳1989 年 25 巻 8 号 p. 860-866
発行日: 1989/08/30
公開日: 2009/03/27
ジャーナル フリーA Markovian decision process with estimation of unknown transition probabilities is used as an important learning control model of stochastic systems in a wide range of applications. Many studies have been devoted and various schemes have been presented for the Markovian decision problem. Most of them stand on the assumption that the process is stationary, in other words, the transition probabilities are constant irrespective of time. In practice, however, they may not be generally constant. Accordingly, it is practically significant to consider the problem in the case of nonstationary processes. Particularly, we are interested in the case of cyclic processes. This is because many real systems may be affected by external conditions generated from cyclic natural phenomena and/or habitual human behavior.
In view of these, we present a scheme of estimation and control for the problem on the assumption that the unknown probabilities are dominated by a parameter which changes its value with cycle T. Every T time instants, under this scheme, we make estimation of the parameter and then determination of control actions to be chosen for the next T instants. The basic idea of designing this scheme is to replace the cyclic process with a stationary process by regarding T instants as a unit time interval and introducing an “extended parameter”. It is proved that the maximum likelihood estimate of the extended parameter converges to the true value and consequently this scheme asymptotically attains control which is optimal in a sense.抄録全体を表示PDF形式でダウンロード (1100K) -
山北 昌毅, 古田 勝久1989 年 25 巻 8 号 p. 867-873
発行日: 1989/08/30
公開日: 2009/03/27
ジャーナル フリーVirtual reference is defined as the setpoint for a closed loop system so that the response tracks the desired path perfectly. It is proposed to obtain a virtual reference for a discrete system by repetitively modifying setpoint over the timed interval in which the desired path is specified. A necessary and sufficient condition that the response tracks perfectly is given firstly. In this learning method, a virtual reference should be determined by learning when a new desired response should be considered. Secondly to improve this shortcoming is studied.抄録全体を表示PDF形式でダウンロード (791K) -
佐伯 正美1989 年 25 巻 8 号 p. 874-881
発行日: 1989/08/30
公開日: 2009/03/27
ジャーナル フリーLearning control can achieve a desired output of a plant with high precision by modifing inputs iteratively from the error data obtained by the previous trial. There is a trade-off between the uncertainty of the plant and properties of error sequences such as convergence rates and maximum values of errors. A design method which can easily accomodate the trade-off is desired.
This paper presents a design method of a learning control system for single input single output discrete time systems. A performance index which can reflect the convergence rate and the effect of modelling errors on the convergence is introduced and a design problem is formulated as a least squares control problem. The optimal controller is given explicitly as a transfer function, which fits for to impliment on computer. The convergence of the sequence of output errors is guaranteed in a finite interval of time.抄録全体を表示PDF形式でダウンロード (930K) -
糀谷 和久, 池田 雅夫, 木田 隆1989 年 25 巻 8 号 p. 882-888
発行日: 1989/08/30
公開日: 2009/03/27
ジャーナル フリーThe direct velocity and displacement feedback (DVDFB) is considered for large space structures with collocated sensors and actuators. It has been known that when the gains of the feedback are negative definite, stability of the closed-loop system is preserved under any perturbations in mass, damping, and/or stiffness. That is, DVDFB is a robust stabilizing control law. The main objective of this paper is to show that, moreover, if the gains are appropriately selected, then DVDFB is optimal control for a quadratic performance index. Obtained conditions for DVDFB to be optimal imply that we need to increase the velocity feedback sufficiently when we increase the displacement feedback. To demonstrate effectiveness of the optimal DVDFB, a simulation result is presented for the Engineering Test Satellite VI, the operation of which is supposed to start in 1992.抄録全体を表示PDF形式でダウンロード (768K) -
森田 英昭, 村田 年昭, 土谷 武士1989 年 25 巻 8 号 p. 889-895
発行日: 1989/08/30
公開日: 2009/03/27
ジャーナル フリーVector controlled induction motor (field oriented control of induction motor) is very prospective actuator instead of direct current motor because of the robust construction, non-expensive and maintenance-free actuator etc. Until now, the vector controlled induction motor system is mainly designed and producted by power electronics technique only. Consideration from the control theory point of view is necessary in order to examine the transient performance as well as the steady state performance because this system is very effective in the control engineering field as well as in the field of energy conversion machine. In this paper, adaptive control system realizing the vector controlled induction motor is synthesized on the basis of nonlinear state equation of induction motor. Under an assumption that secondary flux is detectable, continuous nonlinear compensation inputs are applied to the nonlinear state equation of induction motor and the linearized induction motor model is obtained. Model reference adaptive control system for the speed control is synthesized on the basis of the linearized model in order to construct the robust control system for the parameter variations of induction motor during the operation and the disturbance change. Moreover, the position control system is synthesized and applied to the robot manipulator control to show the effectiveness. Next, under the assumption of non-detectable secondary flux, the similar procedure as before is applied. Since the secondary flux detection is not easy in the industrial field application of the induction motor, a practical method to construct near-vector controlled system is expected. Near-vector controlled induction motor synthesized by the method is compared with the well-known vector control technique (slip frequency control type vector comtrol method). Good transient and steady state performance are shown by the simulation studies.抄録全体を表示PDF形式でダウンロード (872K) -
松尾 芳樹, 中野 道雄1989 年 25 巻 8 号 p. 896-903
発行日: 1989/08/30
公開日: 2009/03/27
ジャーナル フリーA feedback control scheme for PWM systems is considered, on the basis of a conventional triangular carrier wave scheme.
When disturbances such as power supply fluctuation or switching delay exist, the conventional PWM scheme produces output error because of its open loop structure. To cope with this, the present scheme adopts a feedback switching control structure that measures mean output error during each period of the triangular carrier wave and determines the subsequent switching timing to eliminate the error. The scheme is realized by adding a simple circuit to the conventional one. The resulting PWM system has an integral compensation property, thereby the mean output error should vanish in the steady-state. Moreover, when its input and disturbances are of step-type, the response settles down perfectly in 2 periods. Furthermore, a feed forward path can be easily implimented, which makes the input response similar to that of the conventional open loop scheme.
The authors have applied the scheme to a PWM controlled voltage source in a DC electric motor velocity control system. Results of experiments on the system verify the abovementioned merits of the present scheme.抄録全体を表示PDF形式でダウンロード (1678K) -
石川 正俊, 吉澤 修治1989 年 25 巻 8 号 p. 904-906
発行日: 1989/08/30
公開日: 2009/03/27
ジャーナル フリーA new method for detecting n-th moment of output distribution from one or two dimensional array sensors is described. The method is implemented by multilayered parallel processing circuits. Theory of the method using Poisson equation and experimental results are shown.抄録全体を表示PDF形式でダウンロード (406K) -
滝谷 信昭, 新井 優, 澤田 重明, 櫻井 弘久1989 年 25 巻 8 号 p. 907-909
発行日: 1989/08/30
公開日: 2009/03/27
ジャーナル フリーThe nonuniqueness of the IPTS-68 is experimentally estimated in the range from 0°C to 420°C using three standard platinum resistance thermometers and three secondary reference points. The maximum nonuniqueness is found to be less than 0.5mK below 200°C and 1.5mK below 420°C.抄録全体を表示PDF形式でダウンロード (406K) -
佐久間 史洋, 小野 晃, 服部 晉1989 年 25 巻 8 号 p. 910-912
発行日: 1989/08/30
公開日: 2009/03/27
ジャーナル フリーSpectral responsivity distributions of three 0.65μm silicon narrow-band radiation thermometers were measured from 450nm to 1200nm. The temperature scales calibrated based on the spectral responsivity agreed well with those established by the standard tungsten lamp calibration.抄録全体を表示PDF形式でダウンロード (389K) -
長 保浩, 金井 喜美雄, 内門 茂1989 年 25 巻 8 号 p. 913-915
発行日: 1989/08/30
公開日: 2009/03/27
ジャーナル フリーOn realizing multivariable control systems, needless increase of order causes the excessive increase of the computer memory, etc. To overcome above problems, we propose a method of multivarible discrete-time adaptive control system with deterministic disturbances via a polynomial algebraic method.抄録全体を表示PDF形式でダウンロード (386K) -
足立 紀彦, 沼田 伸一1989 年 25 巻 8 号 p. 916-918
発行日: 1989/08/30
公開日: 2009/03/27
ジャーナル フリーConvergence rate of quasi-sliding motion in variable sturucture control system is discussed. First, the upper bound of the size of chattering is given to guarantee the stability of the quasi-sliding motion. Secondly, a relation between the convergence rate of quasi-sliding motion and that of motion in a complete sliding mode is presented.抄録全体を表示PDF形式でダウンロード (357K) -
井出 英人1989 年 25 巻 8 号 p. 919-921
発行日: 1989/08/30
公開日: 2009/03/27
ジャーナル フリーThe organizational substate of brain activity depends upon numerous anatomical connection and pathway. Evoked brain potential called “P300” was discovered while monitoring brain activities of a patient counting the number of sound stimulation.抄録全体を表示PDF形式でダウンロード (1397K)
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