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61.
The authors present a real-time database system capable of collecting and delivering a large amount of information accurately at a high speed and by a simple method. This system has a microprocessor unit (MPU) for each private communication line around the main memory and coordinates the independent parallel operation for a number of these MPUs with the main memory access operation, using a fixed cyclic scan method and having all the MPUs perform multi-operation. Many advantages can be expected when this method is adopted, especially for the monitoring and control of power systems. Degradation of the system can be avoided during an information rush due to accidents, and it can be easily extended when adding to or expanding the power facilities in the future. Excellent daily maintainability can be assured, and a low overall cost can be expected  相似文献   
62.
BACKGROUND/PURPOSE: To develop practical and less invasive techniques for fetal endoscopic surgery, new methods of lifting the uterine wall to allow fetal surgery without maternal laparotomy were developed and assessed. METHODS: Fetal endoscopic surgical procedures, including tracheostomy and umbilical vascular cannulation, were performed using one of the three methods to enter the uterus without maternal laparotomy in pregnant goats (n = 6; 105 to 115 days' gestation): (1) direct uterine lifting with an air-cushion device; (2) indirect uterine lifting, in which the uterine wall was fixed to the maternal abdominal wall using balloon tip ports inserted percutaneously by Seldinger's method, then the maternal abdomen was lifted mechanically; and (3) combined method, in which low pressure CO2 (5 mm Hg for initial inflation and 2 mm Hg for maintenance) was insufflated into the uterus in addition to the indirect uterine lifting cited above. RESULTS: The direct uterine lifting caused massive injury of myometrium and uterine membranes. The creation of intrauterine space and the protection of the membranes were not accomplished effectively by the indirect uterine lifting only. The combined method provided the adequate intrauterine space and excellent endoscopic visibility for completion of the endoscopic procedures with minimal uterine injury. CONCLUSION: The fetal endoscopic surgery may be accomplished simply and safely by the combined method, a novel technique of uterine lifting to allow fetal surgery without maternal laparotomy.  相似文献   
63.
A 77-year-old female was admitted to our hospital because of pyrexia and a right retroperitoneal mass. Leukocytosis and other inflammatory findings were noted. Bone-marrow aspiration revealed hypercellularity with no malignant cells. An additional mass was detected sonographically in the pelvis. The serum concentration of granulocyte colony-stimulating factor (G-CSF) was highly elevated (299 pg/ml). The tumors were removed at laparotomy, and the pelvic mass was found to arise from the ileocecal mesentery. Postoperatively, white blood cell count and serum G-CSF concentrations decreased to normal levels. The mesenteric tumor showed weakly positive immunostaining for human G-CSF, and Northern and polymerase chain reaction (PCR) analyses detected CSF and its mRNA in the mesenteric tumor.  相似文献   
64.
The demand for energy in Japan is expected to increase steadily into the future, and it seems that the importance of nuclear power generation will be heightened more when the situation of our country which is not rich in energy resources is taken into account.

Furthermore, when we consider the present situation that the light water reactors have become common, recent outlook for the supply and demand for uranium resources, trends in the development of the fast breeder reactor technology, etc., the light water reactors are expected to remain dominant in the nuclear power generation of our country until at least the second half of the 21st century.

Based on such a background five PWR utilities in Japan (Hokkaido, Kansai, Shikoku, Kyushu, and the Japan Atomic Power), and Mitsubishi Heavy Industries, Ltd. have jointly started researching the Next Generation PWR which is expected to be the leading nuclear power plant taking place of APWR.  相似文献   

65.
66.
Multiple oxide BaTiO3 gel fibres were prepared by the sol-gel method from Ba(OC2H5)2-Ti(O-isoC3H7)4-H2O-C2H5OH-CH3COOH and Ba(CH3COO)2-Ti(O-isoC3H7)4-H2O-CH3COOH solutions. Relatively long gel fibres of 10cm length were obtained from both solutions in the limited composition region. The latter solution in particular showed a spinnability even when it contained no water. Therefore, the occurrence of spinnability of the solution was considered to be due to the formation of linear polymers composed of bridging acetate groups such as TiO-C(CH3)-O-Ti rather than metalloxane bonding as Ti-O-Ti. Addition of water to the solutions seems to break the bridging acetate bonds and replace some of them by bridging oxygen bonds. The as-drawn gel fibres which were X-ray amorphous crystallized into BaTiO3 ceramic fibres of 5mm average length upon heating above 600 ° C. However, the gel fibres drawn from the sols without water became powdery on heating because of the lack of Ti-O-Ti metalloxane bonds. The crystallization behaviour of the BaTiO3 gel fibres is discussed based on the infrared spectroscopy, X-ray diffraction analysis and thermogravimetric-differential thermal analysis.  相似文献   
67.
An approach to improve the accuracy of the incremental solutions to a nonlinear problem, through a strategy to control the size of the increment, based on stationary of an argumented energy functional, is presented. The problem of control of an optimum step size in the incremental theory is formulated for a fixed number of increments. The variables in this argumented functional are: (i) the incremental displacement vector, (ii) the scalar parameters i which characterize the size of each of the increments, i = 1,..., N, and (iii) a Lagrange multiplier which enforces the constraint that the sum of all the normalized increments, i. e., i is equal to 1. The optimality condition provides us a rigorous approach which gives rise to an iterative procedure because of nonlinearity of the stationary condition. If the number of increments is not prescribed, a noniterative procedure can be obtained, where the incremental sequence is controlled adaptively with less computational effort. The extension of the proposed method to non-selfadjoint problems, where a potential energy function does not exist, is also discussed. Numerical examples demonstrate the remarkable improvement in the accuracy of the solution by optimizing the incremental sequence, as well as the effectiveness of the adaptive control procedure proposed.Paper presented at The 16th International Congress of Theoretical and Applied Mechanics, Lyngby, Denmark, August 19–25, 1984  相似文献   
68.
A new generalized correlation is presented for the low-pressure gaseous viscosity of fluorocarbon refrigerants. The following empirical equation is obtained based on the most reliable experimental data for 16 fluorocarbons: $$\eta \xi = \left( {0.5124T_r - 0.0517} \right)^{0.82} Z_c ^{ - 0.81}$$ where η is the viscosity in μPa·s and ξ is the viscosity parameter defined using the critical temperature T c in K, the critical pressure P c in MPa, and the molar mass M in g·mol?1 as follows: $$\xi = T_c ^{1/6} M^{ - 1/2} P_c ^{ - 2/3}$$ The applicable ranges are 0.6<T r<1.8 and 0.253<Z c<0.282. The availability of the correlating equation for both pure fluorocarbons and their mixtures has been investigated based on the experimental data of these authors and those in the literature. It is found that the present correlation is useful for the prediction of the viscosity of pure fluorocarbons and their binary mixtures at atmospheric pressure with mean deviations less than 1.6%.  相似文献   
69.
Strengthening mechanisms of nickel-base superalloys have been discussed with the background of the Japanese research and development activities in this field. As candidates for materials of intermediate heat exchangers which will be used for a future programme of nuclear steelmaking systems, two kinds of alloys have successfully been developed in Japan. The designs of these alloys have been reviewed from metallurgical aspects including their composition and creep properties. In addition to the conventional methods to strengthen these alloys, such as solid solution hardening or particle precipitation hardening, a grain-boundary precipitation strengthening due to tungsten-rich 2 phase in the Ni-Cr-W system, would be expected as a further advanced method.  相似文献   
70.
Heat shock protein 47 (HSP47), a collagen-specific molecular chaperone, is causally related to fibrotic diseases, including idiopathic pulmonary fibrosis. The identification of Compounds that interfere with the HSP47-collagen interaction is essential for the development of relevant therapeutics. Herein, we prepared human HSP47 as a soluble fusion protein expressed in E. coli and established an assay system for HSP47 inhibitor screening. We screened a natural and synthetic Compound library established at Nagasaki University. Among 1023 Compounds, 13 exhibited inhibitory activity against human HSP47, of which three inhibited its function in a dose-dependent manner. Epigallocatechin-3-O-gallate, one of these three Compounds, is a typical polyphenol Compound derived from tea leaves. Structurally related Compounds were synthesized and examined for their activity, revealing a hydroxyl group at A-ring position 5 as important for its activity. The present findings provide valuable insight for the development of natural product-derived therapeutics for fibrotic diseases, including idiopathic pulmonary fibrosis.  相似文献   
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