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991.
Makoto Murakami Ken-ichi Suzuki Hideki Maeda Tetsuo Takahashi Akira Naka Norio Ohkawa Mamoru Aiki 《Optical Fiber Technology》1997,3(4):320-338
Optical amplifier techniques have led to the installation of large-capacity submarine systems and further capacity increases seem likely. This paper reviews the FSA submarine system, which flexibly operates at both 2.5 and 10 Gb/s and offers maximum transmission capacity of 60 Gb/s for commercial use. The system configuration as well as its characteristics and upgradability will be introduced, including measurement results on time-division-multiplexing/wavelength-division-multiplexing (TDM–WDM) transmission at bit rates of 10 and 20 Gb/s using non-return-to-zero or soliton pulses. To further increase transmission capacity, TDM–WDM techniques that permit more than 10 Gb/s signal transmission in each data channel should be developed. Thus, pulse formats, which include non-return-to-zero, return-to-zero, or soliton pulses, and dispersion allocation in transmission fibers are significant issues. We introduce and discuss our recent results from high-speed (10 to 40 Gb/s) TDM–WDM signal transmission experiments with regard to the above aspects. 相似文献
992.
Monolithic wide-band amplifiers have been demonstrated using AlGaAs/InxGa1-xAs/GaAs pseudomorphic two-dimensional electron-gas field-effect transistors. The amplifiers have yielded an 18.0 GHz bandwidth and a 41.8 dBΩ transimpedance gain with a feedback resistance of 100 Ω. In addition, the dependence of In mole fraction for an InxGa1-xAs channel layer on device and amplifier performance has been also investigated. The gm and the fT in a device, along with the bandwidth, the gain, and the noise performance in an amplifier, have improved as the In mole fraction is varied from 0 to 0.25 相似文献
993.
Matsumiya M. Kawashima S. Sakata M. Ookura M. Miyabo T. Koga T. Itabashi K. Mizutani K. Shimada H. Suzuki N. 《Solid-State Circuits, IEEE Journal of》1992,27(11):1497-1503
Circuit techniques for a reduced-voltage-amplitude data bus, fast access 16-Mb CMOS SRAM are described. An interdigitated bit-line architecture reduces data bus line length, thus minimizing bus capacitance. A hierarchical sense amplifier consists of 32 local sense amplifiers and a current sense amplifier. The current sense amplifier is used to reduce the data bus voltage amplitude and the sensing of the 16-b data bus signals in parallel. Access time of 15 ns and an active power of 165 mW were achieved in a 16-Mb CMOS SRAM. A split-word-line layout memory cell with double-gate pMOS thin-film transistors (TFTs) keeps the transistor width stable while providing high-stability memory cell characteristics. The double-gate pMOS TFT also increases cell-storage node capacitance and soft-error immunity 相似文献
994.
It is shown by computer runs and simple analysis that one hundred million km soliton transmission is possible by means of soliton transmission controls in the time and frequency domains. This means that limitless transmission is possible. The key to success is to reduce noise by the synchronous modulation technique which can also reduce timing jitter and nonlinear interaction forces. The accumulated noise converges to a fixed low level even after limitless transmission.<> 相似文献
995.
Y Yamabe K Ichikawa K Sugawara O Imamura A Shimamoto N Suzuki Y Tokutake M Goto M Sugawara Y Furuichi 《Canadian Metallurgical Quarterly》1997,39(2):198-204
Assessed the effect of co-occurring versus not co-occurring internalizing and externalizing behavior problems on the reasons parents reported for clinical referral of their adolescent child. Reasons for referral were coded for 181 inpatient adolescents, and parent ratings of internalizing and externalizing behavior were obtained for a general population sample of 500 adolescents. Parents concurrently reported internalizing and externalizing behavior as reasons for referral less frequently (p < .0001) than would be expected given the correlation between these two domains in the general population sample. This suggests that the presence of externalizing problems may decrease parents' concern or awareness of internalizing problems, the presence of internalizing problems may decrease parents' concern or awareness of externalizing problems, or both. Implications for the clinical referral of adolescents and for informal parental efforts at helping their children with externalizing and internalizing problems are discussed. 相似文献
996.
Y Ueda N Suzuki K Miyagi K Noda Y Takegaki T Furukawa H Hirose S Hashimoto S Yano Y Miyata M Taguchi T Honda 《Canadian Metallurgical Quarterly》1997,52(4):735-746
A total of 36,780,440 overseas travellers during 1979-1995 (17 years) were quarantined at Osaka and Kansai Airport Quarantine Station, 84,777 travellers reported themselves suffer from diarrhoea. Stools from 29,587 persons were bacteriologically examined. Various enteropathogenic bacteria were isolated from 9,766 (33.0%) patients of the stools examined. Isolated species were as follows: Plesiomonas shigelloides (3,234 cases); Salmonella spp. (2,236 cases); enterotoxgenic Escherichia coli (1,621 cases); Vibrio parahaemolyticus (1,959 cases); and Shigella spp. (1,242 cases). 1,278 different Shigella strains were isolated from 1,242 cases who were thus diagnosed as bacillary dysentery patients. The suspected regions or countries for infection of these cases were analysed. The serovars and antibiotic-sensitivities of the isolated strains were examined. Colicine typing of S. sonnei strains were also done. The results can be summarized as follows. 1) The most cases (53.4%) were infected in India. 2) The percentage distribution of sub-species of the strains was as follows; S. sonnei (57.8%), S flexneri (29.8%), S. boydii (8.4%), and S. dysenteriae (4.0%), respectively. 3) The major colicine type of S. sonnei strains were type 6 and 0. 4) The percentage of Antibiotic-resistant strains of each sub-species was S. dysenteriae (92.2%), S. sonnei (89.4%), S. flexneri (87.1%), and S. boydii (84.9%), respectively. The percentage of Antibiotic-resistant strains of S. flexneri were increased annually. 相似文献
997.
Shiragaki T. Henmi N. Kato T. Fujiwara M. Misono M. Shiozawa T. Suzuki S. 《Selected Areas in Communications, IEEE Journal on》1998,16(7):1179-1189
The optical cross-connect (OXC) system described in this paper increases the operation flexibility and reliability of the trunk-line optical networks used for data communication. It features an OXC node comprised of a photonic switching network and a conventional electric switching network that are connected hierarchically. The operation and management scheme proposed for this OXC system uses the concept of an optical path and an optical section. The OXC system allows hitless network reconfiguration by switching the photonic switches gradually and without interference effects. An experimental OXC network showed that a broken optical path is restored, by rerouting, within 50 ms. Experiments using a LiNbO3 8×8 photonic switch matrix also showed that the OXC system provides photonic hitless switching. These results confirm the feasibility of flexibly reconfigurable and fast-restorable OXC systems 相似文献
998.
999.
Access and metro networks based on WDM technologies 总被引:3,自引:0,他引:3
Iwatsuki K. Jun-ichi Kani Suzuki H. Fujiwara M. 《Lightwave Technology, Journal of》2004,22(11):2623-2630
This paper describes the technical issues of access and metro networks based on wavelength division multiplexing (WDM) technologies, some solutions, and an experimental demonstration. A WDM star access network with colorless optical network units (ONUs) is proposed. For realizing the colorless ONU, two approaches are introduced; optical carrier supply and spectrum slicing. In addition, a WDM metro ring network with scalable optical add/drop multiplexers (OADMs), namely the tapped-type OADM, is proposed to effectively accommodate the large amount of traffic issued from access networks. Prototypes are constructed and used to verify the feasibility of the proposed WDM technologies. 相似文献
1000.
Jun-ichi Nishizawa Akihiko Murai Hiroki Makabe Osamu Ito Tomoyuki Kimura Ken Suto Yutaka Oyama 《Solid-state electronics》2004,48(12):2251-2254
The tunnel injection transit time (TUNNETT) diodes with p+p+n+n−n+ structure were fabricated by liquid phase epitaxy (LPE). About 100 Å tunnel junction (p+n+) was successfully prepared by the double impurity diffusion of Ge and S during LPE growth. Continuous wave (CW) oscillation was realized at 51.520 GHz in the V-band cavity with the phase noise of −60 dBc/Hz at 1 kHz bandwidth. 相似文献