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.
Masaaki KOBAYASHI Yoshihiro MORIOKA
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.
Takahiro INOUE Fumio UENO Satoru SONOBE
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.
Yasuyuki CHAKI Tomoaki SAKAGUCHI Masahiro ASADA Yasuharu SUEMATSU
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 (fγ1.1 THz) is estimated theoretically. The static characteristics are also shown.
Takeshi KONDOH Osamu FUJIWARA Takashi AZAKAMI
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.
Masaaki KOBAYASHI Etsuto NAKATU Hiroaki SHIMAZAKI Yoshitomi NAGAOKA
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.
Masaaki KOBAYASHI Yasutoshi YAMAMOTO Shinichi AKI Yoshitomi NAGAOKA
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.
Makoto HASEGAWA Koichiro SAWA Kunio MIYACHI
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.
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.
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.
Hisaharu YANAGAWA Toshihiro OCHIAI Hiroshi RAIJO Hidehisa MIYAZAWA
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.
Hiroyuki FUJITA Kazuyuki AIHARA
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.
Hiroo UKITA Yoshihiro ISOMURA Hidenao TANAKA
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.
Shigenobu SHINOHARA Minoru ANDOU Masafumi MIYATA Hirofumi YOSHIDA Jun-ichi YOSHIDA Ken-ichi NISHIDE Masao SUMI
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.
Kazunori KANAYAMA Etsuji SUGITA Ryo NAGASE Shin'ichi IWANO
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.
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.
Issam A. HAMID Norio SHIRATORI Shoichi NOGUCHI
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.
K.G. RAVIKUMAR Kazuhiko SHIMOMURA Tomoyuki KIKUGAWA Akira IZUMI Katsuaki MATSUBARA Shigehisa ARAI Yasuharu SUEMATSU
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.
Kazuhito FURUYA Kenji KURISHIMA Saed SAMADI
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.