Operation modes in the system of two mutually synchronized oscillators with both single-ended and double-ended control systems are investigated. The necessary and sufficient conditions for settling common frequency in the system are obtained. It is shown that system in the steady state can be operated in one of several modes. Number of possible modes in the double-ended control system cannot exceed two while in the single-ended control system this number depends on the magnitude of total delay. The necessary and sufficient conditions of existence of separate modes are obtained. The differences between single-ended and double-ended control schemes are pointed out.

This paper studies the experimental application of our new formative evaluation method, Unified Evaluation Method", which combines the pupil's self-evaluation and the teacher's objective evaluation of a pupil's answer to each problem in an achievement test. At first, we give an outline of the unified evaluation method and its data processing system. In spite of easiness of a test practice based on the method, the unified evaluation informations through the test are so new and more detail than ever that they can serve to improve both pupil's self-evaluation and learning process as feedback informations. Next, two examination projects related to our new information of pupil's self-evaluation state are investigated based on practial data: One is the influence due to the differences of both pupil's grade (or age) and sex. Another is the relation between pupil's self-evaluation state and learning activity. By these analyses, we have obtained useful guidance knowledge for the teacher who will make use of the unified evaluation method to know and guide pupils better. Finally, we verify availability of our method (mainly the feedback effect of unified evaluation information) through case studies. Freedback information based on the unified evaluation has proved to be effective for improvement of both pupil's self-evaluation and learning processes.

We proposed a description and coding method of Chinese characters using their structural features. In this paper, we propose a pattern generation method of Chinese characters as an application of the description and coding method. In the method, the generation process of a character can be regarded as a derivation process of sentence which expresses the character, then a Chinese character can be generated iteratively not depending on the numbers of its components and also generated in various shapes by changing some parameters needed for the generation. We can get natural shapes of characters by choosing adequate values of parameters. Many applications using this pattern generation method are considered.

Analytical expressions of lateral resolution of synthetic focus acoustic imaging systems are simply obtained by schematic consideration. A proper choice of a transducer array setup and a compressed pulse waveform yields good performance.

A technique is presented for the automated calculation and the imaging of the electric field around a moving animal. This technique is based on the numerical analysis of an electric field using the finite difference method. Its usefulness in practice is demonstrated by applying it to a free-moving mouse. The mouse is photographed in a 35 mm monochromatic film, and it is transformed in a digital image using a flying spot scanner (FSS). This image is used as a boundary condition for the numerical calculation of the electric field. The distributions of both equipotential lines and electric lines of force are plotted on an X-Y plotter. The intensity distribution of the electric field is presented in the luminance on a CRT display of the FSS and recorded on a film. The surface electric field of the animal body is calculated by extrapolation along the electric line of force and presented in vector patterns. It is shown quantatively that the electric field on the animal body (e.g. nose, back, ears) changes considerably as the animal changes its posture. This method is widely applicable to the objects with any shapes including a human.

A finite-element analysis is presented for predicting dispersion characteristics of layered waveguides with semi-infinite media for piezoelectric surface waves. This approach utilizes the finite-element method and the analytical solutions. The former is used for the layered interior region except the semi-infinite media, while the latter is used for the semi-infinite media, namely the exterior region. Numerical examples on the dispersion characteristics for the piezoelectric surface waves in a waveguide composed of a metal layer of finite thickness on the (001)-plane of the semi-infinite cubic crystal are given.

An improved equivalent network approach in which all of the discrete and the continuous parts of the spectrum are taken into account is described for the guided wave problems in the dielectric waveguide placed on a ground plane. A network representation is derived individually for each of the constituents of the cross section of the waveguide--transmission lines for the uniform regions and lumped equivalent networks for the geometrical discontinuities, namely the sides of the waveguide. These lumped networks are evaluated explicitely by using the Rayleigh-Ritz variational technique. The present equivalent network approach can give more accurate results for the various dielectric waveguides over a wide range of frequencies than the earlier equivalent network approach in which only the coupling between the same order discrete modes at the sides of the waveguide is taken into account.

An n-th power function generator and an n-th rooter have been implemented in current mode. They exhibit good thermal stability and accuracy.

A simple configuration of first-quadrant analog multiplier/divider has been applied to an R. M. S. -D. C. converter. The output voltage of the R. M. S. -D. C. converter is in good proportion to the true R. M. S. value for a D. C., a sine wave, a square wave, a triangular wave and pulse trains. The error is within 1% of full scale.

The optical recording of video signals in real-time and in a high band color mode has been achieved using diode lasers whose light pulse duration is emphasized according to the RF frequency.

Mobile radio propagation tests at 920 MHz were carried out in urban areas. A signal transmitted from a base station was received by a dipole antenna installed near an aluminum case, which simulated the housing of a 20012560 mm3 portable set. Field strength deterioration due to body effect and penetration loss into buildings were measured.

In the previous paper, the chemical composition analysis of Zirconiated tungsten field emitters was reported. In this paper, behavior of Zr atoms on a W-single crystal surface in the nitrogen atmosphere and in the oxygen was investigated by FIM micrograph. Image patterns of the micrograph were taken when the W-single crystal emitter tip of 100 direction was annealed at 1100 for 10 minutes in the presence of 310-6 torr oxygen gas. It seems suitable to explain on the image patterns that zirconium oxide layers are formed. However, the phenomenon of the (100) surface build-up was not observed as much degree in the oxygen presence as in the presence of 610-6 torr nitrogen gas.

The possibility of using SF6 and CF4 as fluorine sources have been studied utilizing the modified chemical vapor deposition (MCVD) method. It has been found that the refractive index change of fluorine doped silica glasses strongly depends on the source materials and the deposition temperature. A maximum refractive index change of 0.05 has been observed using SF6 as the fluorine source. No excess absorption loss resulting from the use of SF6 in the long wavelength region has been observed in single-mode fibers with fluorine and P2O5 doped silica glass cladding.

A method for the solution of the discontinuity problem of SH-type modes in a piezoelectric plate waveguide of crystal symmetry 6 mm is described. The approach is a combination of the finite-element and the analytical method. This method can also be applied to the discontinuity problem of SH-type piezoelectric surface modes by increasing the plate-thickness. The numerical examples on the reflection, transmission and bulk wave scattering of Bleustein-Gulyaev waves by a groove, a rib and an overlay in an oversize piezoelectric plate waveguide are given.

Improvement of the frequency stability in a 3.39 µm He-Ne laser in which the hump profile of the magnetic modulation signal (MMS) is used as a control signal is performed by introducing an enriched isotope into the laser tube.

In this study we present a new Laser Doppler Velocimeter (LDV) with an optical fiber to measure the velocity of blood flow accurately. After the validity of the present method was evaluated by the fundamental experiments, the blood flow profiles in canine femoral arteries were measured in anesthetized mongrel dogs. It was shown that our LDV is a valid and useful velocimeter to measure the phasic blood flow velocity in the artery.

Chaotic response of nonlinear deterministic systems has recently attracted considerable interest of researchers of various branches of science. This paper proposes an application of chaotic phenomena in the field of numerical analysis. Namely, a new method is proposed for designing pseudo-random number generators by making use of chaotic first order nonlinear difference equations. In this paper, in the first place, this design problem is formulated mathematically as an inverse problem of the Perron-Frobenius equation. Here, the Perron-Frobenius equation is the one expressing relationship between a nonlinear transformation generating a certain type of nonlinear difference equations and a density of a distribution function for solutions of such a difference equation, and the inverse problem of the Perron-Frobenius equation is a problem of solving the Perron-Frobenius equation for a nonlinear transformation provided that a density of a distribution function is given. This inverse problem of the Perron-Frobenius equation is then solved under the conditions that the density function is a step function and the nonlinear transformation is a piecewise linear transformation satisfying certain conditions. As an application of this result, it is shown that a uniform random number generator with an arbitrary Kolmogorov's entropy can be constructed. Moreover, a new efficient method is proposed for generating pseudo-random numbers which distribute according to an arbitrary step function type density of a distribution function.

Envelope fading, random FM, and time delay spread are the major degradation factors in digital FM land mobile radio transmission systems using VHF/UHF frequencies. Taking these factors into account, the bit-error-rate (BER) performance of minimum-shift-keying (MSK) with differential detection is theoretically analyzed by using a two-path Rayleigh fading model. The postdetection selection diversity is considered in the analysis to clarify improvement in BER performance. Based on the results, it is shown that a preferable transmission rate exists for a typical land mobile propagation environment.

In a multiprocessor system where the number of processors composing the system is increased, and the memory utilization is raised by improving the execution rate of each processor, the reduction of system throughput caused by the memory access conflicts has to be considered substantially. This paper describes the discussion on such an approach that implements a conflict-free data mapping by the use of some sophisticated address translation between logical and physical addresses. This new addressing scheme of a reorganizable memory structure provides the function that allows each processor easily to distribute the operands to be accessed to completely different memory modules, by interlaying the address translation mechanism called address organizer between logical and physical addresses. This approach permits the memory structure to reorganize so as to make it adaptive to the parallelism contained in the problems themselves, and thus also to accomplish the suppression of memory access conflicts spontaneously. Furthermore, conflict-free data mapping being eventually accomplished through an interface of such a hardware as address translation mechanism, this approach has an advantage that the user's logical address space will not be affected in the least.

This paper shows that the capacitor value spread of the third-order single amplifier lowpass filter can be significantly reduced at the price of a slightly larger resistor value spread. It is found that the sensitivity performance is also improved over that of the conventional equal-resistor design.