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排序方式: 共有875条查询结果,搜索用时 15 毫秒
121.
This paper presents a method for describing and reasoning about the behavior of VLSI circuits within the framework of Extended Temporal Logic. For a reasoning method, an “ω-graph approach” is proposed which is useful in verifying the validity of a design. Not only verification but also other reasoning about circuit properties, such as unknown signal identification, can be treated in a unified way by this ω-graph approach. This approach has been studied as a basis of an expert system for the authors’ VLSI CAD system. 相似文献
122.
The electroencephalograms of 82 infants (between 27 and 37 weeks of conceptional age) recorded during the neonatal period were analyzed and compared with the ultimate clinical evolution. Three groups of infants were identified according to their neurological state at 3 years of age or older: group A: normal (34 infants), group B: minor neurological sequellae (13 infants) and group C: major neurological sequellae (17 infants). A fourth group (group D: 18 infants) died during the neonatal period. The E.E.Gs were classified as: normal, questionably abnormal, moderately abnormal or grossly abnormal. The analysis revealed that E.E.Gs classified as grossly abnormal, were found only in groups B, C and D. Serial E.E.Gs were of more value in distinguishing these groups. Only infants in groups C and D (with I exceptional case in group B) had E.E.Gs which remained abnormal for several weeks or which deteriorated during the neonatal period. This study shows the prognostic value of the E.E.G. recorded during the neonatal period, particularly serial recordings obtained during and after a period of clinical deterioration. A detailed statistical analysis of the E.E.Gs is in progress. 相似文献
123.
Shozo Ishizaka John G. Stockner Katsumi Kobayashi Kunihiro Shima Kenji Katori Humitake Seki 《Water research》1983,17(12):1815-1821
Multi-elemental traces comprising particulate matter in natural water collected during summer in 1978 and 1979 from British Columbia, Canada, were analyzed by α-particle excited X-ray fluorometry. Common elements from all waters examined were Si, Cl, Ca and Fe. The similarity of their distribution in different aquatic environments was statistically analyzed. They were distributed homogeneously in the marine environment but heterogeneously in the freshwater environments. No heavy metals concerned with the environmental standards were detected for all waters examined. 相似文献
124.
125.
An experimental guided millimeter-wave transmission system is constructed employing two 806-Mbit/s digital repeaters, an 8.4-km waveguide line loop, and channel coupling networks. This paper presents its characteristics, such as waveforms, amplitude and delay, error rate, and timing jitter in some detail. 相似文献
126.
Sugimoto Shigetoki Minemura Kouichi Kobayashi Kohroh Seki Masafumi Shikada Minoru Ueki Atsufumi Yanase Tomoo Miki Tetsuya 《Electronics letters》1977,13(22):680-682
The letter reports results obtained with laboratory transmission experiments on high-speed digital signals by optical wavelength-division multiplexing, using a newly developed optical multiplexer and demultiplexer, as well as other high-performance optical devices and fibres. 相似文献
127.
K Miyahara K Yasuura Y Miyata A Seki H Okamoto T Asakura M Murase 《Canadian Metallurgical Quarterly》1998,46(11):1105-1111
From January 1987 through June 1992, 18 patients with poor left ventricular function (left ventricular ejection fraction [LVEF] less than 0.3) underwent elective isolated primary coronary artery bypass surgery. The mean age was 56.4 years (range, 46 to 72 years), and 15 were males and 3 were females. Mean pre-operative LVEF measured by ventriculography was 0.26 +/- 0.03 (range, 0.19 to 0.30). Sixteen patients (88.9%) had a prior myocardial infarction and 9 (50%) had a history of congestive heart failure. Complete revascularization was the goal for all patients, and the mean number of bypass grafts was 3.0 +/- 0.8 per patient. The left anterior descending coronary artery (LAD) was revascularized in all patients. There were no operative deaths. Post-operative LVEF improved significantly from 0.26 +/- 0.03 to 0.42 +/- 0.11 (p = 0.0002), and the regional left ventricular wall motion improved in the diaphragmatic and posterobasal regions (p < 0.01). The patency of the grafts was 93.9% in all, and 100% for LAD. The mean follow-up period was 77 months, and the overall actuarial survival rate was 88.9% at 10 years. During follow-up periods, two patients died of congestive heart failure (CHF), and two required three rehospitalizations because of CHF. The overall cardiac event free rate was 75.8% at 10 years. In patients with poor left ventricular function, surgical revascularization can be performed safely, but congestive heart failure sometimes occurs during follow-up periods and may be the cause of death. Therefore alternate forms of therapy such as cardiac transplantation and/or TMLR should be considered in selected patients. 相似文献
128.
If a loss of vacuum event (LOVE) occurs due to damage of the vacuum vessel of a nuclear fusion experimental reactor, some chemical reactions such as a graphic oxidation and a buoyancy-driven exchange flow take place after equalization of the gas pressure between the inside and outside of the vacuum vessel. The graphite oxidation would generate inflammable carbon monoxide and release tritium retained in the graphite. The exchange flow through the breaches may transport the carbon monoxide and tritium out of the vacuum vessel. To add confidence to the safety evaluations and analyses, it is important to grasp the basic phenomena such as the exchange flow and the graphite oxidation. Experiments of the exchange flow and the graphite oxidation were carried out to obtain the exchange flow rate and the rate constant for the carbon monoxide combustion, respectively. These experimental results were compared with existing correlations. We plan a scaled-model test and a full-scale model test for the LOVE. 相似文献
129.
K Hashimoto H Uchimura Y Seki M Watanabe T Yasuda K Ohsawa 《Canadian Metallurgical Quarterly》1993,113(8):600-603
A simple method using ion-pair high-performance liquid chromatography was established for the rapid and precise determination of synephrine in thirty three species of oriental pharmaceutical decoctions containing Aurantii Nobilis Pericarpium. An ODS column and a mixed solvent system of water, acetonitrile, sodium dodecyl sulfate and phosphoric acid as a mobile phase were used for the separation. Synephrine was eluted without interference of other coexisting components within 15 min. 相似文献
130.
E Imaizumi K Seki Y Kikuchi I Nagata S Matsukuma S Aida S Tamai 《Canadian Metallurgical Quarterly》1993,252(4):209-213
A 44-year-old woman with stage IV non-Hodgkin's lymphoma (NHL) of the left ovary is described. She had an extended hysterectomy and bilateral salpingo-ophorectomy and thereafter received six courses of combination chemotherapy (cyclophosphamide, adriamycin, vincristine and predonisolone; CHOP). The patient is well with no evidence of recurrence at 12 months after surgery. The literature on primary ovarian lymphoma is reviewed. 相似文献