A variational formula is presented for magnetostatic wave resonators. The formula is applied to the magnetized ferrite disk and ring resonators. The resonant mode charts are shown, and it is found that if the aspect of the resonator is optimized, a single mode resonance can be realized on a wide frequency range.

The symmetric first-order Bragg interactions of the optical guided wave in a periodically corrugated dielectric layered structure are investigated for the case of TE mode. The dispersion relation that clarified the propagation characteristics of the optical guided wave in this system is derived systematically by a singular perturbation method using multiple space scales. The obtained formulation is possible to give analytically an estimation of the system, and its numerical results give a designing basis at composing the filter of the optical guided wave and resonator of the semiconductor lasers.

In order to propose necessary raw material purity for obtaining low loss optical vapor-phase axial deposition (VAD) fibers, the contribution of impurities in raw materials to transmission loss for finished fibers has been investigated. Especially, the relation between both SiHCl₃ and Fe impurity concentrations in raw materials and the absorption loss for final VAD fibers is clarified. As a result, the OH absorption loss, which is to be produced by SiHCl₃ impurity, for VAD fibers is independent of the SiHCl₃ impurity amount in raw materials, in contrast to MCVD fibers. In regard to Fe impurity, broadly Fe absorption loss of 0.3 dB/km at 0.8 µm appeared in the VAD fiber which was made from the raw materials containing saturated FeCl₃ impurity. This Fe impurity contribution is discussed in terms of partial vapor pressure. Besides, low loss fiber with a 0.60 dB/km minimum transmission loss at 1.55 µm has been fabricated from unpurified SiCl₄ with 99.17% purity. It is showed that low grade raw materials can be used to fabricate low loss fibers for practical use in the VAD process.

A principle of new Parallel Fourier Transform (PFT) system using a differential transform matrix (DTM) is presented, and its hardware implementation is carried out. The PFT is one of the methods which can execute real-time Discrete Fourier Transform with a low-cost parallel processing. In this paper, the derivation of PFT using DTM is mentioned from the original PFT using polyphase system. It is shown that the PFT using DTM can execute the DFT by 2.5N digital additions or subtractions (where N is the number of input signal points) for each Fourier component, and its hardware is shown. Finally a typical experiment of the PFT is presented.

The degeneracy of TE and TM modes in a transversely magnetized ferrite slab is investigated from the dispersion diagram. The Bragg reflection phenomena in the periodic structures are employed to measure the propagation characteristics of both modes in the vicinity of the degenerate point. A theoretical study of the Bragg reflection phenomena in a surface-corrugated polycrystalline YIG slab is carried out on the basis of an equivalent-circuit model, and then experiments are performed. Existence of the degeneracy of TE and TM modes in the millimeter wave frequencies is confirmed experimentally.

This paper describes the systems aspect of the study which has been conducted to explore the realizability of an on-line library that is capable of providing on-line, to many remote users with original document information. The concept of an on-line library is presented first and then design considerations for a prototype system is described. The prototype system includes a bibliographic information retrieval subsystem, an original document information retrieval subsystem, and a remote terminal subsystem. The bibliographic information retrieval subsystem is capable of interactively retrieving a bibliographic database and a location information database which are stored in magnetic disks. The original document information retrieval subsystem is capable of selectively providing, in accordance with the result of bibliographic information retrieval, pages of original documents which are stored in a direct-read-after-write (DRAW) type optical disk. The remote terminal subsystem performs interactive bibliographic information retrieval and hard-copy recording of original document information by digital facsimile, as well as signal processing and communication control. System performance of the prototype system has been evaluated experimentally, and based upon the evaluation, design parameters for a full-fledged operational system have been described.

A simple meaning representation formalism for Japanese discourse understanding system is presented. Meanings are represented as the clausal forms of logic by utilizing the contextual knowledge and common-sense reasoning can be made as deductive inference by a PROLOG-like procedural interpretation.

A new type of multiple connector for multiple extrusion fiber unit is proposed. This connector has a reciprocal end structure and a simple clamping device such as thermo-shrinkable tube. Average splice loss of 0.31 dB with the maximum loss of 0.52 dB is attained with index maching oil.

It is described that an interactive method of generating easily a pseudo-stereo pair from a two dimensional manually drawn line figure, which has not three dimensional data.