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51.
52.
The failure properties of high-strength fiber splices following proof tests are studied experimentally and theoretically. It is clarified that splice strength can be improved by conducting proof tests and that the strength distribution and the time-to-failure after a proof test can be predicted theoretically. Taking into account the applicability of these results for submarine optical-fiber cables, it is necessary to conduct a proof-test ofsigma_{p} = 2.5 -percent strain on fiber-splicing points. 相似文献
53.
The authors propose a novel approach to force and compliance control of multi-degree-of-freedom (DOF) robot manipulators. The acceleration tracing orientation method (ATOM) is applied to both controllers. The control law is described in the Cartesian space; however, the final command is the acceleration in the joint space. The interactive terms in each joint disturb and deteriorate the joint motion. The disturbance observer cancels out the total sum of these terms and enables each joint to trace the acceleration command. As a result, a robust control is possible in the force task. The testing of the proposed system in a three-DOF robot manipulator is discussed 相似文献
54.
High spectral efficiency combined with power efficiency, is a requirement for high speed digital broadcast satellite systems. The effect of the recovered carrier phase noise and the nonlinearity on the performance of 16-QAM (quadrature amplitude modulation) and staggered 16-QAM is investigated and compared. It is found that for the phase noise, 16-QAM is more degraded for a roll-off factor of less than 0.4. For roll-off factor of more than 0.8, staggered 16-QAM has superior performance. For the nonlinearity staggered 16-QAM is more sensitive for a roll-off factor of less than 0.4. It is concluded that coincident 16-QAM is suitable for spectrally efficient digital broadcast systems 相似文献
55.
Kiyoshi Yoshida Kaname Kizu Haruyuki Murakami Koji Kamiya Atsushi Honda Yoshihiro Ohnishi Masato Furukawa Shuji Asakawa Masaya Kuramochi Kenichi Kurihara 《Fusion Engineering and Design》2013,88(9-10):1499-1504
The modifying of the JT-60U magnet system to the superconducting coils is progressing as a satellite facility for ITER by both parties of Japanese government and European commission in the Broader Approach agreement. The magnet system requires current supplies of 25.7 kA for 18 TF coils and of 20 kA for 4 CS modules and 6 EF coils. The magnet system generates an average heat load of 3.2 kW at 4 K to the cryogenic system. The feeder components connected to the power supply provide current supply. The cooling pipes connected to the cryogenic system provide coolant supply. The instrumentation of the JT-60SA magnet system is used for its operation. 相似文献
56.
57.
Y Harima K Harima N Shikata A Oka T Ohnishi Y Tanaka 《Canadian Metallurgical Quarterly》1998,124(9):503-510
PURPOSE: The ratio of Bcl-2 to Bax expression determines survival or death following an apoptotic stimulus. In order to establish a new predictor of the outcome of treatment for human cervical carcinoma, we investigated the relationship between the expressions of the Bax and Bcl-2 proteins and the response to radiotherapy after the administration of 10.8 Gy. METHODS: A total of 44 patients with histologically proven carcinoma of the uterine cervix, including three with recurrent cervical stump carcinomas, were treated with definitive radiotherapy. The presence of mutations in exons 5-8 of the p53 gene was analyzed by a single-strand conformation polymorphism analysis and DNA sequencing. RESULTS: Forty patients were found to have wild-type p53, and the remaining four had mutant p53. The Bax and Bcl-2 protein expressions prior to radiotherapy did not correlate with response and survival. However, the Bax and Bcl-2 protein expressions after radiotherapy correlated with both response and survival. Bax-positive tumors showed significantly better responses than the Bax-negative tumors after 10.8 Gy radiation (P = 0.0002). In contrast, the Bcl-2-positive tumors showed significantly poorer responses than the Bcl-2-negative tumors after radiation (P = 0.002). Increased Bax expression after the 10.8 Gy radiotherapy was found to be correlated with good survival (P = 0.04). In contrast, increased Bcl-2 expression after such radiotherapy was correlated with poor survival (P = 0.002). CONCLUSION: The levels of Bax and Bcl-2 expression after 10.8 Gy radiotherapy are useful prognostic markers in patients with human cervical carcinoma. 相似文献
58.
Tomoyuki Kitano Takayuki Wani Toshiyuki Ohnishi Jiang Li-Fen Yasushi Kuroda Atsutaka Kunai Kazuo Sasaki 《Catalysis Letters》1991,11(1):11-18
Catalytic oxidation of benzene in the gas phase has been studied as a function of the catalyst composition, reaction temperature and the feed conditions of reactant gases, hydrogen, oxygen, benzene as well as diluting inert gas. The catalyst tested is composed of Pd and Cu(I) ions, both of which are supported on silica gel. If one of the two metal species is lacked from the catalyst, no catalytic activity appears. The product is almost exclusively phenol and some accompanying benzoquinone, in particular at lower temperatures, as minor byproduct.On leave from Hua-Dong Institute of Technology, Nanjing, People's Republic of China. 相似文献
59.
Sakai K. Miyai E. Sakaguchi T. Ohnishi D. Okano T. Noda S. 《Selected Areas in Communications, IEEE Journal on》2005,23(7):1335-1340
The possibility of single-mode oscillation over a large cavity area for photonic crystal lasers emitting at the photonic band edge has resulted in much interest in such materials for new forms of solid-state laser. In this paper, we measure the photonic bandstructure in our sample and identify the lasing band edge. By mapping out the bandstructure at the /spl Gamma/-point, we have observed fine structure at the band edge. The experimental results are in good agreement with the theoretically predicted bandstructure. Above threshold, we observe a lasing peak at 965 nm at one of the band edges. The far-field distribution of the laser is measured, showing an annular profile and azimuthal polarization. Calculations on the far-field distribution at the lasing band edge suggest the annular profile is due to an anti-symmetric resonant mode. 相似文献
60.
The optimization problem is studied for a queueing network consisting of one station and two parallel subordinate stations. After service completion at the first station, the job is divided into two subjobs and each of them enters one of the subordinate stations. The service rate at the first station is controlled in order to minimize the expected total discounted cost or the long-run average expected cost 相似文献