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991.
Kawahara T. Saeki S. Jyouno Y. Miyamoto N. Kobayashi T. Kimura K. 《Solid-State Circuits, IEEE Journal of》1998,33(1):126-132
A fabricated bandgap generator using 0.25-μm Flash memory process generated a stable reference voltage under 4 V, boosted from an external power supply of 2.5 V. The generated voltage was 1.297±0.025 V at a power supply of 4 V±10%; the temperature dependence was +0.7 mV/°C. The characteristics of a triple-well bipolar transistor for the Flash memory process are sufficient for a reference voltage generator; fT is 230 MHz, and HFE is 70. Dynamic operation reduced the average current consumption from 306 to 8.6 μA. Fabricated voltage-doubler circuits generated a voltage 1.8 times larger than that from conventional charge-pump circuits 相似文献
992.
Tensile-strained multiple quantum-well (MQW) structures with camel-back shaped first valence sub-bands are proposed as structures with a large refractive index change caused by current injection. These structures have a high joint density of states at the absorption edge, and the injected carriers in the structures have a long lifetime because of separation in the k-space between electrons and holes. The refractive index change caused by current injection is calculated for camel-back InGaAs/InGaAsP strained MQW structures for 1.55 μm-wavelength light. These structures show a larger refractive index change than the other InGaAs/InGaAsP strained/unstrained MQW structures 相似文献
993.
A Matsumori N Ohashi K Hasegawa S Sasayama T Eto T Imaizumi T Izumi K Kawamura M Kawana A Kimura A Kitabatake M Matsuzaki R Nagai H Tanaka M Hiroe M Hori H Inoko Y Seko M Sekiguchi K Shimotohno Y Sugishita N Takeda K Takihara M Tanaka M Yokoyama 《Canadian Metallurgical Quarterly》1998,62(5):389-391
We present our experience of transcutaneous truncal anaesthesia of the maxillary nerve in association with transmucosal anaesthesia of the sphenopalatine ganglion in surgically assisted rapid maxillary expansion. Twelve patients with a skeletal transverse discrepancy of the maxilla were treated in our department from 1994 to 1995. Maxillary transcutaneous nerve block was done with a Quincke 8 cm spinal needle together with transmucosal anaesthesia of the sphenopalatine ganglion. Mepivacaine without adrenaline and sodium bicarbonate 1/10 was used for truncal anaesthesia and lidocaine-prilocaine cream for transmucosal anaesthesia. A Le Fort I osteotomy, lateral nasal wall osteotomy, pterygomaxillary osteotomy, and a palatal osteotomy were done for all patients before the maxillary expansion. Total anaesthesia of the maxillary area facilitated the operations and appreciably reduced the amount of postoperative pain. The ease of achieving effective anaesthesia before and after operation and the absence of side-effects make this form of anaesthetic particularly useful in surgically assisted rapid maxillary expansion. 相似文献
994.
M Miki T Miura K Sano H Kimura H Kondo H Ishida Y Maéda 《Canadian Metallurgical Quarterly》1998,123(6):1104-1111
BACKGROUND: In patients with ovarian carcinoma, an hematocrit-independent hyperviscosity syndrome is often present. The syndrome is characterized by normal or low hematocrit and hemoglobin concentration, an elevated platelet count, and an increase in clotting factor turnover. Because deep vein thrombosis (DVT) often complicates the course of ovarian carcinoma, the aim of this study was to investigate the possible association of hyperviscosity syndrome with the development of DVT. METHODS: Rheologic estimations of the blood included red blood cell (RBC) aggregation (stasis and low shear), plasma viscosity (pv), blood cell count, and fibrinogen, which were performed before primary surgery and the beginning of perioperative heparin thrombosis prophylaxis on 63 of 65 patients with Stage I-IV ovarian malignancy (according to the staging criteria of the International Federation of Gynecology and Obstetrics). Two patients who had had DVT 5-6 weeks in advance of the study were excluded from rheologic calculations. Thrombosis screening by impedance plethysmography was performed the day before primary major surgery; postoperatively on Days 1, 3, 5, 7, and 10; before each of 6 cycles of chemotherapy (once every 3 weeks); and thereafter once every 3 months during follow-up. All blood tests were also performed on 72 healthy women and 29 patients with benign ovarian tumor the day prior to surgery. RESULTS: All ovarian carcinoma patients, including 7 patients with tumors of low malignant potential, were eligible for surgery, and all except those with Stage IV disease (n = 12) were macroscopically tumor free after surgery. Before surgery, RBC aggregation, pv, and platelet and fibrinogen concentrations were significantly higher (P < 0.05) in cancer patients than in either of the control groups, whereas hemoglobin (hb) and hematocrit (hct) were significantly lower in cancer patients than in healthy women (P < 0.001). Platelet, leukocyte, and fibrinogen concentrations were significantly correlated to disease stage, whereas pv, RBC aggregation, hb, and hct were not. The preoperative pv was significantly higher in patients who later developed DVT (n = 17; 1.46+/-0.13 mPas; P = 0.01) than in those who did not (1.34+/-0.14 mPas). Of all estimated preoperative variables, only pv was a significant risk factor for postoperative and subsequent DVT (RR: 29.84; 95% CI: 1.076-827.16; P = 0.04). CONCLUSIONS: Our results confirm the presence of a hematocrit- and stage-independent hyperviscosity syndrome in untreated ovarian carcinoma patients. In addition, a high preoperative plasma viscosity was a significant risk factor for the development of DVT in the postoperative period and even thereafter. 相似文献
995.
To write a reliable program in an assembly language for microprocessor-based controller, we introduce data abstraction facility into an assembly language. For this purpose, we has designed and implemented ADT-RASM86 and its symbolic debugger. This paper presents the figure of the system and describes how the system is effective for writing a reliable program for microprocessors. 相似文献
996.
FSK signals are generated in an AlGaAs double heterostructure laser by employing an electrical equalising circuit to compensate for its nonuniform FM modulation characteristics. A 10?9 bit error rate is achieved at a 100 Mbit/s data rate in the optical direct discrimination detection with a Michelson interferometer. The optical FSK discrimination detection performance is studied in terms of receiving signal power level and laser spectral linewidth. 相似文献
997.
The densification and microstructure development were studied for Ag-matrix composites containing dispersed Al2O3 particles to examine the effect of inclusions on the densification of composites. The incorporation of Al2O3 particles into Ag matrix hindered densification. Microstructure observation revealed that pores larger than those in the matrix formed around Al2O3 particles during sintering. The pore morphology was dependent on the number density of Al2O3 particles. When the number density was low, pores remained around an Al2O3 particle and coalesced to a large circumferential void at high temperatures. When the number density was intermediate, clusters made of a few Al2O3 particles formed and pores within and around clusters remained up to high temperatures. When the number density was high, the distance between clusters became small and the clusters were connected, forming continuous pores (pore channels). The three-dimensional connectivity of Ag was decreased, and the shrinkage between Ag particles resulted in thickening of pore channels. The presence of these large pores was the origin of the hindrance in densification. 相似文献
998.
Kimura S. Takahashi M. Okuyama T. Tsuchiya S. Suzuki Y. 《IEEE transactions on systems, man, and cybernetics. Part A, Systems and humans : a publication of the IEEE Systems, Man, and Cybernetics Society》1998,28(4):521-527
Adaptation to partial failure is one of the most important requirements for space robotics, since space robots cannot be repaired after they have been launched. We propose a decentralized autonomous control algorithm for hyper-redundant manipulators that uses parallel processing with low-performance processors to achieve this adaptation. In this paper, a number of manipulator joints are locked at a certain angle in a computer simulation and the adaptability of the control algorithm to these failures is assessed. The control algorithm successfully continues its positioning task at a rate of more than 90%, even after half of its joints have failed. The control algorithm is also compared with behavior-based control architecture 相似文献
999.
M Kaji M Gotoh Y Takagi H Masuda Y Kimura Y Uenoyama 《Canadian Metallurgical Quarterly》1998,17(4):388-391
Endogenous or metastatic bacterial endophthalmitis is a severe, sight-threatening infection of the vitreous humor that is only rarely due to Serratia marcescens. We report the case of a hemodialysis-dependent diabetic patient who had endogenous endophthalmitis of the right eye due to S marcescens, presumably from an infected dialysis catheter. The patient had total visual loss in the affected eye, which required enucleation. 相似文献
1000.
Yamada Jun-Ichi Temmyo Jiro Yoshikawa Shokichiro Kimura Tatsuya 《Electronics letters》1980,16(2):57-58
The performance of a 1.6 Gbit/s optical receiver employing a s.a.w. filter as a timing tank is reported. The error-rate characteristics in a p.c.m. transmission system using a 1.3 ?m In-GaAsP laser and single-mode fibres were studied. The average received optical power at a 10?9 error rate was ?28 dBm. In a 15 km transmission experiment, the receiving level was degraded by 2 dB owing to fibre dispersion. Timing phase margin of 75 degrees after 12 km transmission was confined with the self-timed receiver. 相似文献