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.

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.

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.

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.

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 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.

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.