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Volume 6 (1970)
- Issue 6 Pages 483-
- Issue 5 Pages 385-
- Issue 4 Pages 289-
- Issue 3 Pages 195-
- Issue 2 Pages 97-
- Issue 1 Pages 1-
Volume 6, Issue 4
Displaying 1-11 of 11 articles from this issue
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Taro TAJIMA1970 Volume 6 Issue 4 Pages 289-297
Published: 1970
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSWe researched the temperature-charactristics of the forward biased silicon diode for the precise temp. compensation of semiconductor devices.
A) When the forward valtage v, the current density j, temp. T are related by the equation:
j=isexpqv/ηKT (A)
1) The v-T curve is nearly a straight line and the convex value of the curve at 300 °K is 2∼4mV in the range 250∼350°K.
2) The relationship dm0/dv0=1/300 is found, where m0=[dv/dT] 300°K, v0=[v] 300°K.
3) When impurity is diffused in a silicon wafer whose specific resistivity and life time assume prescribed values, and when the pn-junction and the ohmic contact are made in the prescribed condition, the m0-v0 line of the silicon diodes will not depend upon the junction area.
B) If the equation (A) is not valid, in the range where v0 becomes large, m0 deviates from the m0-v0 straight line to large or small according to the temp. coeff. α_??_1/300 of the ohmic part of the silicon diode and in the range where v0 becomes small, m0 deviates to large.
C) For the mesa, the alloy and the planar type silicon diodes which use silicon wafers whose specific resistivities are 0.005∼100Ω·cm, m0 is approximately represented by m0=v0/300-4.07 (m0:mV/deg, v0:mV).
In our experiments, the maximum deviation of m0 from the above representation is about±0.15mV/deg.View full abstractDownload PDF (1610K) -
by Use of Capacitively Coupling CircuitsYoshiharu MASUDA, Bunjiro ICHIJO1970 Volume 6 Issue 4 Pages 298-303
Published: 1970
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSThis paper presents a circuit functioning as a direct reading capacitance meter suitable for measuring capacitances of comparatively high loss materials. This circuit may find a wide range of application in industry.
A measuring instrument to be used for this purpose must be insensitive to any resistance change in the materials and stable for long hours continuous operation.
The minimum equivalent parallel resistance of the specimen which has no influence on the capacitance measurement reaches as low as 1kΩ and the measuring range of capacitance is about 10-2∼103pF at 2MHz. A stability of less than 0.5μA in terms of zero drift was obtained during several hours continuous operation.View full abstractDownload PDF (622K) -
Takao OUCHI, Mitsunori FUKUJU1970 Volume 6 Issue 4 Pages 304-311
Published: 1970
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSD.G. Scorgie and A.D. Schnitzler published papers describing the derivative amplifiers with magnetic core. There remain, however, some unsolved problems concerning the method of detecting only the variation of input and concerning the commutation phenomenon.
The authors reported on two types of magnetic amplifiers for detecting rotating acceleration. These amplifiers can detect the variation of rotating speed by taking the difference in the widths of pulses at the output gates of the first stage amplifiers and the second stage amplifiers. The authers investigated the static characteristics of these amplifiers by using the equivalent circuits based on controlling magnetization curve.
This paper describes the dynamic characteristics of duodirectional DC input type circuit, which are analyzed by representing the action of this circuit by a difference equation and by applying Z-transform to this equation. Almost the same results are obtained in the calculation as in the experiment of the frequency characteristics. It is shown how the saturation flux and the ascending value of flux after resetting affect a detectable low frequency, when the sinusoidal voltage is applied to the input of this circuit.View full abstractDownload PDF (1055K) -
Fumio MATSUMURA1970 Volume 6 Issue 4 Pages 312-318
Published: 1970
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSThis paper is intended to show how the general electric circuit involving diodes and thyristors can be simulated by the block diagram simulation method.
Since each circuit element must be simulated separately, the simulators of diode and thyristor become also necessary. For these simulators, the following functions are required.
1) According to the on or off state of each rectifier, the simulator must indicate a very high-gain or a nearly zero-gain.
2) When these simulators are connected in a computing circuit, they must not be unstable.
3) The discrimination of the on and off states must be done automatically and rapidly.
For the requirements 1), 2), four simulators; namely, types R, A1, A2, and I, each having different frequency characteristics, were designed and made. Each of these is constructed from an operational amplifier, an input resistance, and a feedback impedance using an R-C network.
The discrimination of the on and off states can be made by the comparators and the logical circuits. The reed relays are energized and de-energized by the output voltages of the logic circuits to switch on and off the operational amplifier.
As an example, the practical methods and the results of the simulation of a single phase full-wave rectifier circuit and a thyristor DC chopper circuit are presented.
The results obtained are almost satisfactory to confirm that the simulator may be put to practical use. It is expected that this method may be available to simulate many other circuits involving rectifiers.View full abstractDownload PDF (1069K) -
Tomihide SEO, Takuso SATO, Susumu HATA1970 Volume 6 Issue 4 Pages 319-326
Published: 1970
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSThe Fresnel zone plate is extended, and its application to synthesize optical images is presented.
First, the fixed-width zone plate is introduced. It is a modification of the Fresnel zone plate conventionally used, and has a simple shape easy to produce. The effect of modification is discussed. Then a method to produce the extended zone plate which can focus not only an image of point but also an image of curve is presented. The extended zone plate of fixed width is used in the form of off-axis. This zone plate gives an image with good contrast, and the time to produce the zone plate is saved very much. The required image is obtained as the sum of partial images which are gotten by using the extended zone plate. Several examples of the images synthesized by this method are shown.
Moreover, the 3 D-extended zone plate and the color extended zone plate are proposed to synthesize a continuous three-dimensional image and a color image, respectively.
The zone plate has been drawn by the computer controlled drafter on a paper, and then photoreduced for production.View full abstractDownload PDF (2098K) -
Katsutoshi KURIBAYASHI, Kumeo NAKAJIMA1970 Volume 6 Issue 4 Pages 327-336
Published: 1970
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSThe speed and tension control of the running materials to be processed is a very important problem in textile, paper and other industries. As a large number of control devices regulating speed and tension of the running materials to be processed are needed in those industries mentioned above, these devices are required to be inexpensive and of easy for maintenance. An on-off control device is expected to satisfy these requirements. The authors have designed an on-off controller which is composed of a dancer roller, a pilot motor and a mechanical variable-speed drive. Since the pilot motor rotates in both regular and reverse directions according to the polarity of the signal from the dancer roller through a pair of relays, the problems of stability and self-sustained oscillation should be studied.
This device has two non-linear elements. One is the system of relays, the other is the pilot motor, the speed characteristics of which are different when it starts and stops. However, the relays and the pilot motor are combined into a single non-linear element because the speed vs, time curve is decided uniquely when the pulse-width of the output of the relay is given. Thus, the calculation of transient response and self-sustained oscillation has become possible in the time domain.
The following stability corndition is the result of the present study: A/B>γ0/6+β0/2
where A/B is the ratio of the gain of the feedback compensation to the gain of the major feedback loop, γ0 is the time constant of the speed of the pilot motor when it starts and β0 is that when it stops.View full abstractDownload PDF (1368K) -
Yoichi KAYA, Masumi ISHIKAWA1970 Volume 6 Issue 4 Pages 337-345
Published: 1970
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSAn impulse response model is a most general model of a linear autonomous system, so that many papers have dealt with construction of a model of this kind from system data, assuming that the system is linear and autonomous. Validity of this assumption, however, is doubtful in many cases. Development of methods for testing fitness of an impulse response model is then required.
Problems to be discussed are 1) how to test the fitness of a given impulse response model and 2) how to test the validity of the assumption that the system is linear and autonomous.
Both problems are solved by seeing whether all higher order correlation functions of the error and the system input vanish. Student's t-test or Hotelling's T2-test is applied to problem 1) and the sign test to problem 2). Some associated problems of these methods are also discussed with results of simulation tests on a computer.View full abstractDownload PDF (1046K) -
Goro MIURA, Kazuo SATO1970 Volume 6 Issue 4 Pages 346-355
Published: 1970
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSThis paper deals with the second-order nonlinear control system of which the restoring force and the damping factor contain sinusoidal functions of the displacement. A control system taken up in this paper is the following oscillator with an automatic phase control.
x2=x1
(1+α)x2+(1/√β+α√βcosx1)x2+sinx1=γ
The parameters α, β, γ are all positive, but their magnitudes are not restricted. Therfore, there may be cases in which the damping factor changes alternatively between positive and negative.
First, a phase plane z=x1+jx2 is transferred into a new w plane by the conformal representation with w=exp(jz)=y1+jy2. The stable and unstable singular points in the w plane are, respectively, (√1-γ2, γ) and (-√1-γ2, γ) Locating on the unit circle.
A limit cycle, if exists, is a closed curve enclosing an origin of the w plane, and is the stable second-kind limit cycle. In order to obtain the region of its existence, the Liapunov's function is taken as
V(y1, y2)=R2exp(-2α√β/1+α·y2/R)>0
where R2=y12+y22. The closed curve V(y1, y2)=C is determined corresponding to dV/dt>0 as follows:
C=exp[-2√β(1+γ)]
The second-kind limit cycle may exist in the region lying between this closed curve and the unit circle R=1. A first-kind limit cycle does not exist.
Next, the region of initial values converging to the stable singular point is obtained constructing the Liapunov's function by the method of Infante.View full abstractDownload PDF (1158K) -
Tadayoshi FURUYA, Yutaka SUZUKI, Katsuhiko FUJII1970 Volume 6 Issue 4 Pages 356-365
Published: 1970
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSThe method proposed in this paper is able to identify a certain class of nonlinear systems which consist of some nonlinear gains and linear systems. The connection among the elements within the nonlinear system is assumed to be known a priori.
The output of the nonlinear gain is approximately represented by the polynomial of the input whose coefficients are unknown parameters. The dynamics of the linear system is represented by using the impulse response whose discrete samples are also considered to be unknown parameters. These parameters are determined to minimize the sum of squares of the error between the actual output and mathematical model output. Some linearization techniques such as the Gauss-Newton method are usually used where the model's parameters are corrected iteratively so as to approach the corresponding system parameters, but the convergence of iteration is not always guaranteed. In this paper, it is proved that a technique to vary the step size of the correcting action makes it possible to dicrease the error criterion monotonously. Further this method uses such an algorithm that some parameters corresponding to the coefficients of the polynomial are estimated successively from lower order terms to higher ones without estimating all parameters at once. By means of this algorithm, the values of the parameters at the first iteration can be taken in the neighborhood of the absolute minimum point so that the estimated parameters may converge to the true values in a few iterations.
Through the digital simulation, it is shown that the dynamic characteristics of the nonlinear system, which has a nonlinear gain and a linear system connected in series, can be correctly estimated by the above method. It is also confirmed that the method is applicable even when the linear system within the nonlinear system is not self-regulatory.View full abstractDownload PDF (1121K) -
Hidenori KIMURA1970 Volume 6 Issue 4 Pages 366-372
Published: 1970
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSIn this paper, a control problem and a stabilization problem for linear plants with disturbances are considered by using a game-theoretic approach.
A class of linear differential games with fixed terminal time is solved by an elementary method. This game may be regarded as an extension of the well-known regulator problem in control theory. Analogous to the regulator problem, the optimal strategies are given by linear feedback control laws whose gain matrices are obtained by solving a matrix Riccati equation. Unlike the regulator problem, however, this equation is not necessarily solvable. It is shown that this equation is solvable if and only if the solution of a certain linear matrix differential equation is nonsingular.
Using these results it is shown that, under a certain condition, there exists a linear feedback control law which brings the state of the system to an arbitrary neighbourhood of the origin whatever a square-integrable disturbance the system undergoes. This result suggests the possibility of extending the concept of controllability defined by R.E. Kalman for linear dynamical systems to systems under conflict or systems with disturbances. It is also shown that, if the value of the disturbance is limited by the norm of the current state vector, there exists a linear feedback control law which makes the system asymptotically stable.View full abstractDownload PDF (826K) -
Algorithm for Solving the Fredholm Type Integral EquationKimio KANAI1970 Volume 6 Issue 4 Pages 373-382
Published: 1970
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSApplying Pontryagin's maximum principle to the optimal control problem of distributed parameter system described by linear partial differential equations, its two point boundary value pro blem is reduced to the problem of solving the Fredholm type integral equation of the second kind.
In this paper, metal piece heating process with the furnace of first-order lag is taken up as an example, and two different algorithms are proposed in order to solve the above problem. First of all, numerical solutions are derived applying Step-wise Steepest Descent Method in which the optimal step-size is derived analytically by minimizing the performance value of each iteration, and the convergence of the performance value is compared with that of Continous Steepest Descent Method. Next, an application of the eigen function expansion method to the above problem is described. As the kernel function is separable in this heating process problem, its kernel takes approximately the from of Pincherle-Goursat type and the eigen value is obtained easily to give an analytical solution, and its numerical result is compared with that of Steepest Descent Method.View full abstractDownload PDF (1061K)
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