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71.
Tatekura K. Yamamoto H. Wakabayashi H. Niiro Y. 《Selected Areas in Communications, IEEE Journal on》1986,4(7):1104-1111
The development phase of the OS-280M optical submarine cable system is finished, and currently the mass production lines for the system are arranged so as to satisfy the specific performances and the reliability requirements for the TPC-3 system within its system life of 25 years. KDD developed the reliability assurance system of the repeater components, which began three years ago. In this paper, we will introduce the reliability design of the OS-280M system and will report on the reliability test results obtained until the present time. In conclusion, it will be demonstrated that all of repeater components, i.e., optical semiconductor devices, monolithic IC's, several kinds of optical devices, and conventional components could satisfy the reliability requirements for the OS-280M system. 相似文献
72.
A novel process has been developed to construct PZT-polymer 1-3 micro composites for high-resolution ultrasonic imaging for medical diagnosis. The key technology is the lost silicon (Si) mold process, by which PZT micro-rod arrays have been successfully fabricated with the finest rod size being 7 μm, the highest aspect ratio exceeding 15. Such fine-scale high-aspect-ratio PZT structures, which are essential for realizing high imaging performance, have never been realized by any conventional technique. 相似文献
73.
Shinan Wang Xinghua Li Katsuhiro Wakabayashi Masayoshi Esashi 《Journal of the American Ceramic Society》1999,82(5):1339-1641
A deep reactive ion etching (RIE) technique that uses sulfur hexafluoride (SF6 ) gas has been developed for lead zirconate titanate (Pb(Zr,Ti)O3 , PZT) three-dimensional microfabrication from PZT ceramic blocks. The etching was performed by using an inductively coupled plasma that was generated in a narrow-gap vacuum chamber. The etch depth was 70 µm with a maximum etch rate of 0.3 µm/min and a selectivity of PZT to the electroplated nickel mask of >35:1. The sidewalls of the PZT structures were tapered, with base angles of ∼75°. Both positive RIE lag and unexpected ultrafine-slit etching phenomena were observed. 相似文献
74.
Makoto Wakabayashi Takayuki Kohno Tokutaro Kimura Satoshi Tamura Masahiko Endoh Satoru Ohnishi Toshikatsu Nishioka Yoshikatsu Tanaka Toshitaka Kanai 《应用聚合物科学杂志》2007,106(2):1398-1404
Many additives are commercially used to add more favorable qualities to films. The bleeding process by which the additive in a film comes to the surface is considered. A new bleeding model of additives in a polypropylene film under atmospheric pressure was investigated. Solubility and diffusion are found to be important for explaining this bleeding process. It was found that the experimental results were explained more precisely by assuming a two‐step transport process between the crystalline regions and the amorphous ones. The solubilities and diffusion coefficients of UV‐stabilizers such as 2‐(2H‐benzotriazol‐2‐yl)‐4‐(1,1,3,3‐tetramethylbutyl)phenol and 2‐(2H‐benzotriazol‐2‐yl)‐4‐methylphenol were determined at 40°C. The difference between the saturation solubilities and the diffusion coefficients of UV‐stabilizers was discussed by comparing with the results of molecular dynamics (MD) simulation. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007 相似文献
75.
Ideas for improving continuous teleoperation and operator performance despite time delays using force-reflecting hand controllers. They have been tested on the Japanese Engineering Test Satellite-7 (ETS-7). Predictive display and predictive simulation are used 相似文献
76.
A 2.4 Gbit/s, four WDM optical fibre transmission experiment over 459 km using six Er-doped fibre amplifiers in the 1.55 mu m wavelength region is presented. The results confirm the possibility of WDM multiple optical amplifier repeater transmission systems.<> 相似文献
77.
T. Tago Y. Shibata T. Hatsuta K. Miyajima M. Kishida S. Tashiro K. Wakabayashi 《Journal of Materials Science》2002,37(5):977-982
Silica (SiO2)-coated rhodium (Rh) nanoparticles were prepared using a water-in-oil microemulsion of polyoxyethylene (15) cetyl ether, cyclohexane and water. SiO2-coated Rh nanoparticles were obtained by hydrolyzing metal alkoxide (tetraethylorthosilicate, TEOS) in the solution containing Rh complex nanoparticles followed by thermal and reduction treatments. In the SiO2-coated Rh nanoparticle, a Rh particle with an average diameter of 4.1 nm was located nearly at the center of each spherical SiO2 particle. The SiO2 layer was approximately 15 nm thick. Since the Rh particle was wholly surrounded by SiO2, the Rh particle of the SiO2-coated Rh nanoparticle exhibited an extremely high thermal stability. Furthermore, the porous structure of the SiO2 layer could be controlled by the hydrolysis conditions of TEOS. 相似文献
78.
An error index for the stress intensity factor (SIF) obtained from the finite element analysis results using singular elements is proposed. The index was developed by considering the facts that the analytical function shape of the crack tip displacement is known and that the SIF can be evaluated from the displacements only. The advantage of the error index is that it has the dimension of the SIF and converges to zero when the actual error of the SIF by displacement correlation technique converges to zero. Numerical examples for some typical crack problems, including a mixed mode crack, whose analytical solutions are known, indicated the validity of the index. The degree of actual SIF error seems to be approximated by the value of the proposed index. 相似文献
79.
Taga H. Yamamoto S. Mochizuki K. Wakabayashi H. 《Photonics Technology Letters, IEEE》1989,1(10):332-333
A directly modulated 1.519-μm distributed-feedback laser signal was transmitted over 233 km of single-mode fiber consisting of dispersion shifted fiber and conventional step-index fiber to minimize the dispersion penalty. The power penalty after the transmission was 0.25 dB. The results show the effectiveness of an optical amplifier repeater system for high-speed long-haul fiber optic transmission 相似文献
80.