Accuracy of PTD and PO is compared with the exact solutions for a plane wave diffraction from a large conducting disk, ten wavelength in diameter. The excellent accuracy of PTD is demonstrated, while serious errors of PO in polarization prediction are pointed out. The multiple diffraction turned out to be the main reason for the PTD error.

In this letter we investigate the leaky modes supported by a M type slab weveguide which is made of three dielectric layers imbeded in a cladding. Some numerical results are shown.

Some sampled servo signal characteristics of an optically switched laser diode (OSL) head are examined. Wobbling signal amplitude increases with bias current and is proportional to the light beam deviation from a track center at around the threshold current corresponding to the low reflection part of the medium. It is confirmed that OSL head tracking can be realized using the sampled servo method.

A single-mode 110,000 optical scanning switch was fabricated by cascading a 110 single-fiber switch and a 11,000 ten-fiber-ribbon switch. The average insertion loss was 1.5 dB, and the loss variation throughout 1,000 switching cycles was less than 0.2 dB. The maximum switching time was 3.5 sec.

The propagation constant, the effective index, the effective guide thickness and the refractive index has been measured by using the method of a variable spacing of a high-index film and the waveguide surface. The spacing can be varied by the electrostrictive element.

Described is FM modulation distortion in the light output of a semiconductor laser frequency-modulated with a triangular wave current. The variation of instantaneous FM modulation efficiency is caused by both the thermal effect of FM modulation and the optical feedback from a focusing lens.

Failure probability of a split ceramic alignment sleeve in an optical fiber connector has been predicted based on slow crack growth theory. Applying the theory to split zirconia ceramic alignment sleeves, a failure probability of 10⁴ for 20 years is predicted and the value is expected to decrease to almost zero when an appropriate proof test is introduced.

An influence of a waveguide facet reflection on hybrid-integrated LD gate characteristics was studied. The gate gain is sensitive to a change in the waveguide-gate gap width. An AR coating of the waveguide facet is essential for suppressing the gain-ripple due to a change in the gap width.

2.4 Gbit/s 4 WDM transmission experiment using a traveling-wave laser amplifier has been demonstrated. The result indicated that there exists the appropriate optical input power to the laser amplifier in order to minimize both interchannel crosstalk penalty and beat noise induced penalty.

In the time domain, the single-element directional coupler will act as a digital frequency doubler, which converts a train of unipolar pulses into a train of faster bipolar pulses. This paper provides simulated output pulses for input Cosine half waves using measured phase and attenuation characteristics to show good agreement with both the theoretical response and previous experimental results.

Low temperature dependences of complex permittivity for MgO and SrTiO₃ substrates are measured accurately and nondestructively by using the TE₀₁₁ mode of a cylindrical cavity in the microwave region.

Corrosion of contact surface on the printed circuit board both for thin Au plated (0.1µm) and for thick solder plated (10µm) were examined in SO₂ environment. The corrosion was evaluated by contaminant film and contact resistance. The Au plated surface easily degraded. On the contrary, the film on the solder plated surface grew slowly. Acceptable low contact resistance was found.

In this letter the formation of palladium-oxides on AgPd 70 and AgPd50 contacts caused by mechanical switching actions is reported. Further, palladium-oxides are found to show non-linearity of contact resistance when contact potential drop gets over about 0.3 V.

In this letter a newly developed method of plasma anodization is proposed. This is worked on by irradiating the ultraviolet light onto the specimen of Al thin films. It is observed that the ionic current through the specimen is increased by uv light. And, it could be concluded that the uv irradiation has an effect to enhance the anodization rate.

Numerical simulations of GaAs MESFET's with deep acceptors Cr in the substrate are made for the first time. Acceptors are found to play an important role in determining I-V curves, whether they are shallow or deep. To minimize short-channnel effects, the acceptor density in the substrate must be high.

This letter describes theoretical characteristics of the electron diffraction transistor and its inverter circuit. The electron wave diffraction due to a transverse potential grating is analyzed taking thermally induced dispersions into account. The switching time is estimated as 0.4 ps at 77 K.

Cross-modulation distortion of dual gate GaAs MESFETs in the gain controlled operation mode has been studied analytically and experimentally, yielding a conclusion that setting the ratio of the structural parameters (mβ₂/β₁) and the pinch-off voltage large is effective for reducing the distortion.

A novel electronic device named Space Charge Limited Insulator Tetroide (SCLIT), which uses space charge limited current in insulator of a metal-insulator structure is proposed. A possibility for high speed response (f_γ1.1 THz) is estimated theoretically. The static characteristics are also shown.

Leakage current shift of CMOS inverter circuits due to stored charge during Electron Cyclotron Resonance (ECR) plasma exposure was smaller than Reactive Ion Etching (RIE). But in case applied RF power is turned off at the same time of microwave power off, gate insulator breaks down. Also, electrostatic chuck cooling (ESC cooling) for cooling wafer makes stored charge larger.

A comment on the feasibility of TV-on-the-wall" using flat-panel CRTs is presented along with a discussions of their problems. The flat-panel CRT satisfies the fundamental characteristics required for a color TV in principle, such as the luminance, color quality and the screen size. The important problems, however, are how to achieve a uniform picture and how to fabricate the tube such that the support structure does not affect tube performance.

The change of luminance of AC powder electroluminescent panels with temperature has been improved by controlling temperature dependence of impedance of the panels' insulating layer.

To improve picture quality of a color-under VCR, chrominance bandwidth expansion is studied using subsampling technique. It is concluded that line offset subsampling and field offset subsampling are effective methods of improving reproduced picture quality.

To study lower sideband enhancement, three kinds of modulation methods are applied to recording. Compared with results of experiments using a VCR and simulations, it is concluded that the order of magnitude of lower sideband enhancement is AM, Dual-frequency, FM with lower modulation index.

Quadrature amplitude modulation (QAM) was found to suitable for the bandpass type frequency characteristic of magnetic recording/reproducing channels. A method of 20 Mbps signal recording using 32 QAM coded modulation is described.

Brightness pattern golssiness G_BP of pearls was measured by the system, which consists of a CCD-TV camera, an image processor, etc. The G_BP was considered to be roughly suitable for the physical glossiness of pearls.

The integration-type indistinctness degree glossiness for curved surfaces was newly introduced, so the measuring was stabilized and the automatization of the measuring was also rialized.

This letter describes the potential attenuation mechanism of the charged human body due to walking on the polymer floor. A model is proposed for analyzing the human body potential. The validity is verified by measuring the potentials of the charged acrylic sheet.

A low sensitivity high-Q band-pass switched-capacitor (SC) filter with zero worst-case sensitivity at every arttenuation zero is proposed. The proposed SC filter is synthesized using parasitic-insensitive SC integrators with reduced capacitance spread.

The cross-polarization characteristics due to a perfectly-conducting cylinder for an electric dipole source are rigorously analyzed in the case that the dipole is oriented in any direction. Some numerical examples of the far field scattering pattems and the cross-polarization discrimination (XPD) are obtained.

For investigating the pantograph discontact phenomena, this letter describes the statistical measurements of the discontact properties in the sliding-contacts. The current-dependences of the discontact and the discharge rates are elucidated.

In our previous paper, we had proved that the non-closure properties of the class of sets accepted by three-way two-dimensional alternating finite automata (L[TR2-AFA]) under several operations, i.e., row catenation, row closure, row cyclic closure, and projection operations. This letter investigates the remaining closure properties of L[TR2-AFA], especially under column-directional operations, showing that this class L[TR2-AFA] is not closed under column catenation, column closure, or column cyclic closure operations, too. Thus, we have settled the almost closure properties of L[TR2-AFA].

There exists a method to simultaneously obtain test paths and test data in conformity with the structure and path conditions of objective program. This paper discusses a method to simultaneously obtain a set of test paths of satisfying a desired coverage rate and test data of testing the test paths.

The information compression by LSP analysis-synthesis is a promising method in the sense that the speech with relatively high quality can be synthesized with small amount of codes. Up to present, coding of LSP parameters have been investigated from various viewpoint. It rarely happens that the speech information changes rapidly with time. And, there exists a correlation between two time-series of LSP which are adjacent on the frequency-axis. We have already proposed the coding method which is considered these two features of LSP parameters. However, there still exists redundancy which is lying on the sorrounding LSP parameters. This paper proposes a new LSP coding method which employs the fuzzy reasoning. Using the fuzzy reasoning, it becomes possible that the useful information lying on the surrounding LSP parameters influence the new coding method. Applying the proposed method, the coding experiment and the quality evaluation of the synthetic speeches were performed by comparing our previous method on condition that analysis order is 10. Experiments confirmed two principal results. First, number of transmitting bits which is required to suppress the spectral envelope distortion to 1 dB or less, decreases to 20.8 to 34.7 bit per frame. Second, this coding method needs about 2.8 kbit/sec for transmitting the vocal tract information to suppress the spectral envelope distortion including the time distortion to 1 dB.

A systematic synthesis is presented to realize any digital filter into a power-wave digital filter. After three canonical matrix representations are introduced, a set of key concepts which comprises cascade interconnection of digital two-ports, pole localization, and computability is presented for the canonical cascade synthesis of lossless digital two-ports. The synthesis procedure consists of global decomposision and local decomposition. The procedure is so general as to give a unified solution to arbitrary frequency responses realization, and is so useful as to find new circuit structures. The synthesized circuits are of robustness and modularity. An illustrative example is included.

We consider the computation of an upper bound to error probability in Trellis-Coded Modulation (TCM) schemes in sequence dependent channnels. In its most common form, the pairwise-state" technique is applicable to this class of channels. However, it entails a degree of complexity that may not acceptable, because the dimension of the matrices involved in pairwise-state calculations is the square of the number of states, and the number of states, say N, equals the product of the code states and of the channel states. In this paper, we derive an error probability bound based on a computational technique which avoids the consideration of N²N² matrices. It is based on the computaion of the transfer function of a graph with N1 nodes, and whose branch labels are NN matrices rather than scalars. we also describe some looser bounds which simplify the computation of error probability over intersymbol interference (ISI) channels, and show numerical results of the methods applied to trellis coded 16-QAM with 2-symbol ISI.

An intersectional optical switch structure based on the field induced refractive index variation was fabricated by the use of LPE grown GaInAsP/InP MQW wafer. The first switching operation in a MQW intersectional switch structure was achieved. The field induced refractive index variation in quantum well was estimated to be around 0.45% at the applied field of 13 V/µm from the experimentally obtained switching ratio. Finally a small X-type modulator with low chirp, low power saturation is proposed which make use of the reflection phenomenon caused by field induced rafractive index variation instead of absorption phenomenon as in conventional absorption type modulators.

We have pressented here, for the Control Unit (CU) of Benes Interconnection Network (IN), a new fast parallel computational model named as; Cyclic Cube Engine (CCE), which depends on the Cyclic Cube topology, where the total number of processing elements is φ such that φN^(11/h), h is an arbitrary integer, such that 2hlog N. N is number of the data items consisting the permutation. We have presented on this model parallel algorithm for parallel settings of Benes IN in order to realize arbitrary permutation with a setting time of O(h log₂ N); (assuming N is base 2) using φN^(11/h) processors (i.e., φN). This bound could be achieved by accelerating the parallel setting algorithm by function call of another very fast algorithm named as the accelerator. We have also, proven in the appendix of this paper, that our construction is within the lower bound of setting Benes IN for arbitrary permutation for general nonshared model when φN. Using these algorithms we have constracted a fast parallel setting algorithm to set the switches of Benes IN for arbitrary permutation in parallel time of O(h log₂ N) where is hlog₂ N. The parallel setting algorithm has been constructed depending on the CCE as the main computational structure suitable for setting Benes IN in parallel.

Two new segmentation methods for Japanese syllable recognition were proposed and were experimentally compared. In one of these methods, the adaptive power envelope template was compared with the logarithmic power envelope of input speech, and the most suitable position was searched. The second difference of the clipped power envelope was calculated and the point where is gave the maximum value was detected as the segment boundary in another method. A segmentation rate improvement of 2.1%, and the accurate syllable recognition rate of 90.5% in average for 10 speakers were obtained by the later method.

Based on the similarity between the neural and the immune networks, a modified PDP model is adopted to simulate the idiotype networks of the immune system. Major modifications peculiar to immune networks are the introduction of time delays and the bilateral and asymmetric interaction between units. Simulation results show nonlinear behaviors of networks such as hard oscillations and chaos. The behaviors are closely related to the structure of networks. It is suggested that the analysis of the immune system can inspire new scheme in parallel distributed information processing.