In this letter, we deal with the minicomputer system developed for imaging the degree of the decrease in a peak frequency of the first heart sound measured at 25 points on the chest surface and the similarity of one. This system provides a useful and powerful means to understand the diagnostic information rapidly.

A frequency modulator basically consists of an amplifier and a resonator employing a varactor diode, and the linearity of frequency modulators has been analyzed and discussed looking at the resonance frequency calculated from the capacitance-voltage characteristics of a varactor diode. However, as the oscillation frequency of the frequency modulator increases, it becomes essential for designer to evaluate the influences on the modulation linearity by the phase characteristics of the amplifier. This paper discusses the influences on the modulation linearity by the phase characteristics (the phase slope (or group delay) and the cross frequency fc) and by the capacitance-voltage characteristics of varactor diodes, and the design of a UHF frequency modulator utilizing a hybrid integrated amplifier, is described. It is pointed out that, although the capacitance variation ratio n(log C(V)/log V) is less than 2, the capacitance variation ratio increases with the varactor diode bias voltage so that good modulation linearity can be obtained. Furthermore adopting a push-pull mode of operation, two UHF frequency modulators are connected to obtain a wideband frequency modulator (the bandwidth is f025 MHz). Finally a feedback-type frequency modulator operating at 6 GHz is discussed, as comparison to the result of the UHF frequency modulators.

A carbon granule microphone with carbonaceous electrodes, which is lower in cost and more convenient for mass production than the conventional microphone with gold plated electrodes, was studied as a telephone microphone. A molded piece made from a mixture of synthetic resin and carbon powder can be used for the back electrode and paint made from it can be used to coat the dome electrode. A new microphone, whose sensitivity is as high as a conventional microphone, shows higher resistance. This means that the efficiency of the new microphone seems to be slightly less. However, the sensitivity change in the new microphone under excitation by voice is less than that of the conventional microphone. The new microphone sensitivity dependence on DC input power is almost the same as that of a conventional microphone.

A short channel MOS FET with 1-1.5 µm channel and double boron-ion implantation has been designed as a high speed static RAM element. High speed properties and short channel effects are compared among the MOS FETs with 1.5-100 Ωcm substrate and several deep/shallow implant dose combinations. It is found that 40 Ωcm substrate or so with 4/45/31011 cm2 deep/shallow implant dose combination is most desirable.

An extraction method of contour lines from a contour map on the market and their restoration method are described. Twin tracing points (clockwise and counterclockwise) are used to trace and extract line components from the map which involves not only contour lines but also block components such as symbols and numerals. To implement the tracing successfully, ending conditions and setting manners of the twin tracing points are dealt with taking various kinds of curves into consideration. By this method, sets of the coordinates of traced contour lines, step numbers of tracing, and moreover, the thickness and length of traced contour lines, the coordinates of their skeleton lines are obtained. Since some contour lines are cut off by the elimination of symbols and numerals, to restore them a finding method of a pair of cut off points which must be connected is also described. For the restoration, an adjacent graph is introduced with an example, and several cases of relations between a graph and set of contour lines are dealt with. A determining algorithm of a pair of connecting candidates is given. Finally, as the results, an original contour map of a mountainous area, extracted contour lines, skeleton contour lines and a connected (by straight lines) contour map obtained through the twin-tracing-points method and restoration method are illustrated.

We reveal that the degree of pattern separation in a two-layer random neural net with inhibitory connection has a favorable property for pattern classification. We also consider the effect of the number of connections between the two layers on the above property.

Any imperfections of a dielectric thin-film waveguide can be mainly classified into the irregular boundary interfaces and the refractive-index fluctuations. In this report we demonstrate a simple method to obtain the scattering losses caused by the two typical imperfections in terms of the coupled power coefficients.

One of the main loss factors in the optical fibers fabricated by the vapor phase axial deposition process is at present residual OH ions which are originated mainly from an oxy-hydrogen flame. Residual OH ions show an influence on loss increase, especially, in the long wavelength region. OH-ion behaviors in the porous perform, transparent perform and drawn fibers are studied with use of an infrared spectroscopy and fiber transmission measurement. In order to realize low OH content VAD fibers, the dehydration effect of halide vapor on the porous perform is investigated experimentally. Dehydration effect of thionyl chloride on the porous perform is studied by various heat treatment temperature. As a result, residual OH ion content in the drawn fiber was reduced from 30 ppm to 20 ppb and the attained minimum loss of dehydrated fiber was 0.5 dB/km and 0.28 dB/km at 1.3 µm and 1.6 µm wavelengths, respectively. Present investigation clarified that the VAD fibers are applicable to an optical transmission system in the long wavelength band. We compare the loss peak values at the wavelengths of 1.39, 1.24 and 0.95 µm among several optical fibers fabricated by different method. Especially, the VAD fibers dehydrated with SOC12 show abnormal peak ratios at the wavelengths.

The pulsed HF chemical laser of the HI/SF6 system can be excited to the sixth HF vibrational level, and the spectra of this system coincide with those of the HF chemical laser of the H2/F2 system. The pulsed HF chemical laser of the HI/SF6 system can therefore be used as an oscillator or a preamplifier for the power-amplifier of the H2/F2 system. The power of a pulsed HF chemical laser of the HI/SF6 system is said to be poor in comparison with other mixed systems, but the use of a Blumlein-discharge circuit to initiate the electric discharge proved to be effective. An electrical efficiency of 3.9% for a pulsed HF chemical laser of the HI/SF6 system was obtained, and both the electrical efficiency and the output energy of this laser system were comparable with those of the HI/SF6 system.

A pulsed HF chemical laser of the HI/SF6 system can be used as an oscillator or a preamplifier for the laser power-amplifier system of the H2/F2 system. The HF chemical laser of the HI/SF6 system is predicted to extract more energy than the other mixed systems, but the results of calculations based on a simulation model were not in agreement with experiment. In this paper, our calculation was based on the assumption that the HI molecules dissociated upon the initiation. The pulsed HF chemical laser of the HI/SF6 system is here treated theoretically, utilizing the constant-gain methode by a pulsed chemical laser code. The pulsed HF chemical laser is characterized by the laser output energy, power and pulse width. The calculated results in accordance with the assumption that 1% of SF6 and 25% of HI are dissociated by the electric discharge, are in good agreement with the experimental data for a pulsed HF chemical laser of the HI/SF6 system with the Blumlein-discharge circuit.

A CCD with resistive input gate and this design are proposed for improving linearity of the dynamic injection method. Fundamental performances of the device are analyzed theoretically.

This paper describes an effective method for coping with short-line-interruptions in high-speed data transmission, and effectiveness of the technique is shown by the experiments.

A high speed, 4 K word by one bit static Random Access Memory (RAM) has been developed, using Diffusion Self-Aligned (DSA) MOS technology. High speed and low power operation was achieved by combining the following refined devices and new circuit technology; high gain DSA MOS FETs as drivers, Reverse DSA (RDSA) MOS FETs with low threshold voltage (VTAR0 V) as power reduction switches, full wave rectifier substrate bias generator and dual X-decoder circuits. The present RAM operates on a single 51 V external power supply. Its typical performances are; 28 ns chip enable access time (CL33 pF), 300 mW active power dissipation and 50 mW stand-by power dissipation.

The tunable filter which utilize the collinear acoustooptic TE-TM mode conversion is discussed. A novel filter structure is proposed intended for realizing desired filter performances by the adjustment of waveguide parameters. Design examples are presented to confirm the advantage of this structure.

Evaporated Ni thin films being formed on a bulk Ni electrode were eroded by a single break are in resistive circuit. A model of the crater formation was proposed from observations of the eroded area by Scanning Electron Microscope.

Ultimate low loss single-mode fibers have been prepared by reducing excess due to structural imperfections as much as possible. Loss mechanisms based on the fabricated fibers have also been analyzed. Transmission loss has been reduced almost down to the intrinsic material loss. Minimum loss was 0.2 dB/km at 1.55 µm. It was made clear that the dispersion can be reduced to zero at this wavelength region by increasing the waveguide dispersion. It has been confirmed that such single-mode fibers are very useful for high capacity and long distance transmission media.

This paper deals with the effect of core deformations caused by a periodic external on the transmission characteristics of an optical fiber. For simplicity, the distribution of the periodic external force is assumed to be a sinusoidal, and the slab waveguide model is analyzed to clarify the loss mechanism of the round optical fiber under the periodic external force. In theoretical investigations, the Green's function for the displacements of the axis of a slab waveguide model is obtained. By using the Green's function of the displacements and the mode coupling theory, we clarify the relation between the radiation loss due to the core deformations and the external force. It is found that the radiation loss of the fundamental mode or the lowest order mode decreases as the spatial wave number of the periodic external force and the cladding radius increases. Experimental investigations on the excess loss of the single mode fiber have also been made, the results can be explained qualitatively by the theoretical results of the slab waveguide model.

A general optical lithography technique has been improved by using UV light and by making a fine adjustment in the close contact between the flat mask and the optically polished surface of the piezoelectric material. A fine pattern of alternate 0.7 micrometer lines and spaces of SAW transducers IDT was fabricated, which was confirmed in an excitation of SAW at 1.385 GHz on LiNbO3.

Based on appearing frequencies of directional changes in contour line tracing, a chain coding method using three directional differences is described. Smoothed contour lines and 2-3 bit-compression compared with Freeman's chain code are obtained applying the method on 20 contour lines of lakes.

The DOMINATING SET problem in a graph is the problem of determining, for a given integer k1, whether G has a dominating set D satisfying |D|k. In this paper, we will prove that the DOMINATING SET problem in cubic planar graphs (i.e., regular graphs with vertex degree 3) is NP-complete.