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991.
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   
992.
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   
993.
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   
994.
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   
995.
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   
996.
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   
997.
Using eyes undergoing phacoemulsification followed by implantation of a foldable acrylic intraocular lens (IOL) designed for small-incision cataract surgery, a multi-center study was performed to compare a non-steroidal ophthalmic solution (0.1% diclofenac) to a steroidal ophthalmic solution (0.1% fluorometholone) in preventing cystoid macular edema (CME) and inducing disruption of the blood-aqueous barrier determined by laser flare cellmetry. The incidence of CME, noted in 3 out of 53 eyes (5.7%) receiving diclofenac and in 29 out of 53 eyes (54.7%) receiving fluorometholone, was significantly lower in the diclofenac group. The flare in the anterior chamber was also significantly lower in the diclofenac group; when compared between eyes with and without CME, the amount of flare was significantly higher in the former group. These findings suggest that diclofenac effectively prevents CME following cataract surgery and that CME is closely related to the breakdown of the blood-aqueous barrier.  相似文献   
998.
BACKGROUND: Although diagnostic peritoneal lavage (DPL) is a well-established, reliably objective method of diagnosis of intraperitoneal injury, it is too sensitive to be used as an indicator for emergency celiotomy. Therefore, since the development of ultrasonography and advanced computed tomographic scanners, the role of DPL has been markedly reduced. Despite such remarkable advances, however, radiologic diagnosis of intestinal injury cannot always provide definitive results, and DPL may still be valuable in such instances. We have developed a new DPL criteria specifically designed to aid in the diagnosis of intestinal injury and have evaluated its effectiveness. METHODS: From August 1988 to December 1995, we performed DPL in 250 patients with blunt abdominal trauma and analyzed the diagnostic accuracy of our new criteria. We used the standard quantitative white blood cell (WBC) criterion for detection of intestinal injury supplemented by a positive-negative borderline adjusted to WBC > or = red blood cell (RBC)/150, where RBC > or = 10 x 10(4)/mm3. RESULTS: Our criteria had a diagnostic sensitivity of 96.6% and a specificity of 99.4% for intestinal injury after exclusion of 57 patients in whom DPL was performed within 3 hours or after 18 hours from the time of injury. In 133 patients with hemoperitoneum, emergency celiotomy was performed in only 48; the remaining 85 patients with negative DPL based on the WBC criterion avoided surgery, and conservative management resulted in no complications. CONCLUSION: With the proposed criteria, DPL can be used to diagnose or exclude intestinal injury even in the presence of hemoperitoneum.  相似文献   
999.
NAD(P)H:quinone oxidoreductase 1 (NQO1) is a flavoenzyme that catalyzes two-electron reductive metabolism and detoxification of quinones and their derivatives leading to protection of cells against redox cycling and oxidative stress. To examine the in vivo role of NQO1, a NQO1-null mouse was produced using targeted gene disruption. Mice lacking NQO1 gene expression showed no detectable phenotype and were indistinguishable from wild-type mice. However, NQO1-null mice exhibited increased toxicity when administered menadione compared with wild-type mice. These results establish a role for NQO1 in protection against quinone toxicity. The NQO1-null mice are a model for NQO1 deficiency in humans and can be used to determine the role of this enzyme in sensitivity to toxicity and carcinogenesis.  相似文献   
1000.
We have developed a digital real‐time simulator of Power Electronics Controllers, so‐called FACTS (Flexible AC Transmission Systems) Controllers and/or Custom Power by using MATLABTM/SIMULINKTM and dSPACETM System. This paper describes the modeling and the calculation accuracy of a UPFC (Unified Power Flow Controller) model. Hence, the developed simulator operates at a large time step, in order to improve simulation accuracy, a correction processing of the switching delay is implemented into the UPFC model. Calculation accuracy of the real‐time UPFC model is at the same level as EMTDCTM results. We confirm stable operation of the developed UPFC model by connecting a commercial real‐time digital simulator (RTDSTM). © 2006 Wiley Periodicals, Inc. Electr Eng Jpn, 155(1): 19–26, 2006; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20200  相似文献   
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