About the circuit using the storage time of junction diode, many reports are published. However, the pulse width converter and diode amplifier with high accuracy are difficult to be performed, using the storage, effect of diode itself.
Therefore, we used a simple circuit construction, where the series inductance is connected with the storage effect diode, and then improved the linear characteristics between the forward current and total delay time, by limiting the low speed circuit (the pulse width is about 0∼0.25μs, 0∼0.1μs).
In this circuit, Q of junction capacity increases rapidly after the recovery time of diode, then the resonance circuit is constructed with the junction capacity and series inductance. Therefore, the sharp pulse as the end pulse is obtained.
In this paper, the storage time equation in the circuit is calculated, and it is proved that the series inductance improved the linear characteristics between the forward current and total delay time from calculated results.
Also, the dependence of delay time on series inductance and dependence of delay time on drive voltage are explained by our experiments for the storage time of diode.
The above experimental data show that the calculated result and experimental one are coincident succesfully.

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In order to detect the change of mean value of AC voltage, smoothing circuit is generally used. However, the response time of the circuite is long, because of having large time constant compared with period of input signal.
A circuit is designed in order to detect the change of mean value of AC voltage as quickly as possible, that is, the DC output of the circuite is obtained within a period of one cycle of input signal. This circuit is constituted of a integrating circuit and a holding circuit where the charge of the integrating condenser is transfered quickly to holding the condenser using SCR. This circuit is scarcely affected by the noise in the signal to the circuit, since it has integrating function.
From experimental results of the circuit detecting the change of commercial frequency voltage, it is shown that this circuit has satisfactory performance in accuracy and responsibility.

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This paper deals with a new type of nonlinear control device for controlled system with a dead time or a higher-order lag.
The nonlinear control device consists of two parts, one is a conventional PID controlling element which is a cascade combination of a PD and a PI controlling element, and the other is a special phase-lead compensating element connected in parallel with the PD one.
Principle, design, construction and characteristics of the nonlinear control device are described in detail. Taking into account of the influence of the saturation of manipulated variable, the frequency characteristics of the nonlinear control device and the step responses of the control system are studied by use of a digital computer.
As a result of the experiment, it is found that the transient responses for the step change in set point of the system with this nonlinear control device are better than the ones with the optimally set PID controller.

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The controllability and observability of composite time-varying linear systems are studied. These systems are obtained by connecting time-varying linear finite dimensional systems in parallel, in tandem, or in feedback loop.
Emphasis is placed on the preservation of controllability and observability of time-varying linear systems. The controllability and obervability matrices which do not require knowledge of the transition matrix are used.
The conditions for composite systems to be totally controllable (observable) provide significant structural information of composite systems.
In addition, the equivalence of the controllability and observability of a feedback connection to that of a tandem connection is established.

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In recent years the behavioure of on-off control system with feedback compensation has been improved, and some setting conditions of the on-off controller have been proposed. However one of the defects by these setting conditions in practice is that the offset cannot be reduced to zero.
In order to get time optimal response and zero offset when the set point is largely changed stepwise a new setting condition of the feedback compensated on-off controller which has the first order lag and dead time element is proposed.
As a result of the analog computer study on the responses of the on-off control system, it is found that the proposed setting condition is especially effective to the large step change of the set point

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This paper is divided into two parts. The first is concerned with the performance loss of the Wiener-Kalman filter (or the Bayesian estimation process) due to incorrect information associated with the values of covariances of system noise and of observation noise. By evaluating the actual, calculated and optimal covariance matrices, the difference equations are derived to describe evolution of three error matrices. It is clearly shown for the first order system that the Wiener-Kalman filter (or the Bayesian estimation process) is rather insensitive to variations in noise levels.
The remainder of this paper is devoted to the investigation of the mutual relations between the estimation problem and the regulator problem from the viewpoint of performance loss. It is well known that the estimation problem is the dual of the noise free regulator problem. We demonstrate here that there still exists the duality principle between the two problems in the sense of performance loss.

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In this paper, two results with respect to the noninteracting control problem in multivariable linear systems are showed.
The first half shows that the noninteracting control problem is a variational one. Necessary and sufficient conditions for the linear (time variant and time invariant) multivariable control system to be the noninteracting control system are shown with the aid of variational method used in the theory of invariance.
The second half shows that it is possible to obtain the noninteracting control system by state variable feedback. Sufficient conditions for the noninteracting control system to be constructed by state variable feedback are obtained by using the concept of relative orders.

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It becomes often necessary to extract an adequate linear model out of the observed response data of an unknown system. The usual process for this is first to assume the model transfer function with a certain number of unknown parameters and then fix their numerical values so that the agreement of the model response with the observed one is optimum in a certain sense.
Even though the skill in the first step, the assumption of the model form, is often more crucial effect than the other on the quality of the model performance, very little to rationalize this step has been done yet so far.
In this report, a new method for this purpose is proposed which enables us to estimate quantitatively such things as the width of the significant frequency band, the equivalent lag order within the above frequency band and the approximate distribution of the poles of the observed system, All of these can bedone through a straightforward data reduction routine by a digital computer without resorting to any kind of human judgement, even though the scope of application of the method is limited to monotone or nearly monotone systems.

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In this paper, the noninteracting control of nonlinear multivariable systems is studied.
In the first place, it is showed that the noninteracting control problem is avariational one.Necessary conditions and sufficient conditions for the nonlinear multivariable control system to be the noninteracting control system are shown with the aid of variational method used in the theory of invariance.
In addition, the design problem of the noninteracting control system is discussed. It is shown that it is possible to obtain the noninteracting control system by state variable feedback. Sufficient conditions for the noninteracting control system to be constructed by state variable feedback are discussed by using the concept of relative orders.

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An optical information processor deals very easily with two dimensional data. However, the electro-optical coupling in a real time basis becomes hard, because of the necessity of using transparency variations, such as photographic films, as input data.
This paper presents a new method of transforming electric signals into a two dimensional optical transparency variations, on a real time. The process consists of some ultrasonic vibrators placed in a tank filled with water that control in each instant the locations of the ultrasonic waves traveling through the water. Using the Schlieren method, only the light diffracted by the ultrasonic waves can be obtained. So, the presence or absence of these waves will be transformed into transparency variations.
As an application, a reference pattern was generated with a pattern recognition device. When the reference character matches with the unknown one, the light caught by a photomultiplier will be maximum (Optical Pattern Matching Method). As a first trial, figures from “0” to “9” were used to be recognized; though it is still in an initial step, it was possible to classify each figure. By other hand, using a K.D.P. light modulator as an optical shutter, the possibility to apply this device as a characted printer was confirmed. The character “E” was generated and its picture was taken.

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Many measuring devices may be suggested using laser beam. For instance, many trials of an accurate length measurement counting the number of moving interference fringes through an interferometer have been already made. This method permits a precision of the order of a wave length over several meters.
This paper presents a measuring device based on this principle; many improvements are introduced as to create a new characterized method, by which fundamental studies and experiments are done. Detailed examinations are dedicated especially to detection, and counting and indication processes. On the former, instead of using two slits to detect the fringes, three slits are used. By this recourse the measuring accuracy is improved. In addition, to stabilize the output signal of the photo-electric converter, an amplifier are introduced. On the latter, the electronic circuits are simplified introducing an error correcting counter to eliminate a slight difference between the unit of measuring length and the length corresponding to a single movement of the fringes.
Meanwhile, to get more precise length measurement, “an optical path difference amplifier” is contrived. It is verified experimentally that measurements up to several tenths of a wave length is possible.

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The conventional approach, using the 2nd order correlation functions, is insufficient to analyse stationary non-Gaussian random processes. For such analysis, it is necessary to use higher order correlation functions of the processes.
This paper presents a 3rd order correlator using the random voltage method. In this method signals are converted to the corresponding binary signals, and therefore it has some benefits which simplify the signal multiplication and delaying.
The device consists of three main parts; a generator of uniformly distributed random numbers, a tape recorder with 7-channels equipped with an endless magnetic tape, and control circuits.
Binary random numbers are obtained by combining the binary pseudorandom numbers from a generator with random pulses obtained by shaping the physical noise of a thyratron. Then these random numbers are converted to uniformly distributed random numbers by a D-A converter.
The correlator is designed so that it repeats a cycle of computing and delaying operations automatically.
Th device is used to the analysis of the noise generated by a blower, and its non-Gaussian property is proved. The results show the usefulness of the correlator.

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A method for determining the speed of a moving paper strip by applying a correlation technique is described.
The inherent irregular transparency of a paper strip is observed with photocells through two slits that are placed at a distance along the direction of strip movement. The crosscorrelation function of these two photoelectric signals gives a way of determining the strip speed. The delay given to the upstream signal so as to make the correlation between the signals maximum informs the time taken for the movement of the strip from the upstream to the downstream detecting point.
The observed signals are made binary according to whether they are greater or smaller than each mean value and then sampled. Upstream signal is delayed with a fixed stage shift register and is multiplied by the downstream signal. The delay time can be continuously varied by changing the shift pulse period, which is the same as that of sampling. Following up of the peak of the correlation function is performed simply by controlling the sampling frequency or the delay time so as to minimize the signal of the derivative of the correlation function.
The shift pulse frequency thus controlled is directly proportional to the speed of the paper strip. The variance of fluctuation of the correlator output due to finite time averaging is evaluated in the case where the observed signal is binary whose points of zero crossing are distributed at random with its autocorrelation function φ_xx(τ)=e^-2λ|τ|. And the fluctuation of the shift pulse frequency controlled by the correlator output is also estimated.
Experimental results were in good agreement with the theoretical consideration.

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