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991.
This paper presents, for potential application to network failure restoration, an optical digital cross-connect system (DCS) which uses both a photonic switching network and an electric DCS. It is shown that a system constructed of LiNbO3 8×8 switch matrices and semiconductor traveling-wave optical amplifiers (TWA's) could be applied to metropolitan area networks. An experimental optical DCS system has been designed and fabricated which incorporates both LiNbO3 switch matrices and TWA's, and with it, line-failure restoration, a fundamental operation of optical DCS, has been successfully demonstrated  相似文献   
992.
To optimize the Vth of double-gate SOI MOSFET's, we fabricated devices with p+ poly-Si for the front-gate electrode and n+ poly-Si for the back-gate electrode on 40-nm-thick direct-bonded SOI wafers. We obtained an experimental Vth of 0.17 V for nMOS and -0.24 V for pMOS devices. These double-gate devices have good short-channel characteristics, low parasitic resistances, and large drive currents. For gates 0.19 μm long, front-gate oxides 8.2 nm thick, and back-gate oxides 9.9 nm thick, we obtained ring oscillator delay times of 43 ps at 1 V and 27 ps at 2 V. To our knowledge, these values are the fastest reported for this gate length with suppressed short-channel effects  相似文献   
993.
ATM adaptation layer protocol   总被引:1,自引:0,他引:1  
The ATM adaptation layer (AAL), as defined in the International Telecommunications Union (ITU) 1990 recommendations, will enhance the services provided by the ATM layer to support the functions required by the next higher layer. The question of what that next higher layer is has been a matter of controversy from the beginning of the AAL study. AAL protocol specifications are key to the success of B-ISDN services. They must be developed in a timely fashion, in cooperation with other standardization bodies such as ISO and the ATM Forum  相似文献   
994.
The heat capacity of C70 has been measured by adiabatic calorimetry between 14 and 320 K. The orientational phase transition is observed as a broad hump in the heat capacity curve, which is strongly influenced by small amount of solvent remaining in the sample.  相似文献   
995.
A battery-operated 16-Mb CMOS DRAM with address multiplexing has been developed by using an existing 0.5-μm CMOS technology. It can access data in 36 ns when powered from a 1.8-V battery-source, and 20 ns at 3.3 V. However, this device requires a mere 57 mA of operating current for an 80-ns cycle time and only 5 μA of standby current at 3.3 V. To achieve both high-speed and low-power operation, the following four circuit techniques have been developed: 1) a parallel column access redundancy (PCAR) scheme coupled with a current sensing address comparator (CSAC), 2) an N&PMOS cross-coupled read-bus-amplifier (NPCA), 3) a gate isolated sense amplifier (GISA) with low VT, and 4) a layout that minimizes the length of the signal path by employing the lead on chip (LOC) assembly technique  相似文献   
996.
This paper deals with a diagnostic and monitoring system for assessing the integrity of pipe branches, during the operation of the nuclear power plant. This system have been developed under the concept of “easy to use without any sophisticated analysis” and “portable”. The accuracy of the diagnosis is based on the model optimization subsystem, which automatically modifies the numerical vibration model so as to fit its natural frequency to the actual natural frequency. The information obtained by this system may be reflected to a maintenance program of the plant to assure more reliable operation of the plant.  相似文献   
997.
We report the case of a 51-year-old Japanese man with a unique pustulosis. He had multiple erythematous plaques and numerous pinpoint pustules on the trunk and extremities resembling pustular psoriasis. Histologic features revealed a fully developed intraepidermal abscess filled with neutrophils and disrupted epidermal keratinocytes. Mild leukocytosclastic vasculitis was seen in the underlying dermis. A direct immunofluorescence study revealed IgM, Clq, C3 and fibrinogen deposits in the dermal vessels. The patient had also sternoclavicular hyperostosis. We think that this represents a unique type of pustular vasculitis distinct from pustular psoriasis.  相似文献   
998.
We report herein the rare case of a 65-year-old man found to have esophageal intramural metastasis from cancer of the gastric cardia. Endoscopic examination initially revealed an infiltrating ulcerative tumor of the gastric cardia involving the esophagogastric junction, as well as a submucosal tumor of the lower esophagus. A total thoracic esophagogastrectomy with lower mediastinal lymphadenectomy was performed, and the resected specimen demonstrated that both the cardia and esophageal tumors were adenocarcinomas with the same cellular differentiation. As lymphatic invasion and metastases to the paracardial and mediastinal lymph nodes were observed, the esophageal submucosal tumor was considered to be an intramural metastasis from the carcinoma of the gastric cardia resulting from extensive lymphatic spread. The patient died of recurrent disease 9 months after the resection. This case report serves to demonstrate that intramural metastasis may be a local indicator of the systemic spread of disease in patients with gastric carcinoma, as it is in esophageal carcinoma.  相似文献   
999.
Changes in benzodiazepine binding sites labeled by [3H]flunitrazepan (FNZ) in twenty discrete brain regions of rats made tolerant to and dependent upon pentobarbital were examined. Animals were rendered tolerant by intracerebroventricular (i.c.v.) infusion with pentobarbital (300 micrograms/ 10 microliters/ hr for six days) through pre-implanted cannulae connected to osmotic mini-pumps. The pentobarbital dependence was assessed 24 hr after abrupt withdrawal from pentobarbital. In the tolerant rats, a significant increase in [3H]FNZ binding sites was found in layer IV of frontal cortex and the molecular layer of olfactory bulb. [3H]FNZ binding sites in the pentobarbital dependent rats were significantly increased in layers I-III and V-VI of frontal cortex, caudate-putamen, olfactory tubercle, globus pallidus and ventral pallidum, in addition to those observed in the tolerant group. There was, however, no significant difference in the hippocampus and several regions in the hindbrain in either pentobarbital-treated group. Taken together with characteristics of subtypes of benzodiazepine receptors and changes in GABA-benzodiazepine receptor complexes elucidated in our previous studies, these findings suggest that both types of benzodiazepine receptors are involved in the development of pentobarbital intoxication mediated by GABAA receptors.  相似文献   
1000.
Ultrafine oxide particles were synthesized by introducing aqueous solutions of metal salts into a high-temperature r.f. inductively coupled plasma (the spray-ICP technique). The particles synthesized were spherical for ZrO2, Y2O3, Sm2O3, La2O3, δ-Al2O3, TiO2 (anatase), β-Bi2O3 and CuO, plate-like for Nd3O2, Cr2O3 and Pr2O3, polyhedral for PrO2, CeO2 and γ-Fe2O3, cubical for NiO, MgO, CaO, Co3O4 and Mn3O4, bar-like for SnO2 and ZnO, and foil-like for β-PbO and MoO3. The products of the alkaline earth group except for magnesium, were hydroxides and/or carbonates, spoiled by atmospheric H2O and/or CO2. The particle morphology suggests that particle growth is controlled predominantly by the gas-solid reaction occurring on the surface of nuclei condensed from the gas phase. Some of the oxides revealed a particle morphology characteristic of their crystal structures.  相似文献   
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