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51.
A GalnAsP edge-detecting photodiode was coupled with an SiO2-TiO2 single-mode waveguide in a simple hybrid integration scheme. The newly developed edge-detecting photodiode with a window region was used to improve photodiode durability. 相似文献
52.
In studies of shock-induced phase transition of ordered pyrolytic graphite to a diamond-like phase, the lowest transition onset pressure was observed at 19.6 GPa. The phase transition in that case was considered to be martensitic. In the present study ordered pyrolytic graphite with voids between particles was loaded at pressures up to 15 GPa using a planar shock wave propagating along the basal plane of the graphitic crystal structure. As a result, both diamond-like carbon and diamond were observed in the postshock sample. The phase transition of graphite to diamond was assumed to occur by the release of distortional energy stored in the graphite particles, that is, diffusional-controlled reconstructive mechanism, on the basis of the data by high resolution electron microscopy together with electron energy loss spectroscopy. 相似文献
53.
Motonobu Yoshikawa Hiroshi Nakajima Takeshi Inada Yasushi Harada Masahiko Amano Yuji Nakata 《Electrical Engineering in Japan》1995,115(7):29-39
A new practical method is proposed which gives a quasi-optimal solution of the dynamic load-dispatching problem formulated by a multiconstraint multiobjective optimization problem. Here, the multiple constraints are rate reserve constraints and power flow ones, and the multiple objectives are fuel cost and CO2 emission. The proposed method is an integration of the following three techniques: (1) “Group Dispatch Scheme,” which is developed by the authors, is used to satisfy a violated constraint easily. This scheme consists of three steps. The first step is to classify all generators into two groups. One is the group which should be more loaded to satisfy the violated constraint, and the other is the should-be less loaded group. The second step is to add some load to the former group, and to subtract the same load from the latter. The third step is to dispatch each group load to each groups generators, respectively; (2) the dynamic load-dispatching algorithm is used which provides, in practical time, quasi-optimal generation trajectories; (3) the conventional weighting parametric method is used to obtain a Pareto optimal solution of multiobjective problems. The effectiveness of the method is clarified by a computer simulation on the actual power system of Kansai Electric Power Company. 相似文献
54.
Hiroyuki Nakahira Masakatsu Maruyama Hideshi Ueda Haruyasu Yamada 《The Journal of VLSI Signal Processing》1993,5(2-3):133-140
This paper describes an image processing system using Image Signal Multiprocessors (ISMPs) adapted to gray-level image preprocessing for image analysis and image enhancement. It is composed of four ISMPs, five 1H-delay-lines, two 512×512×8-bit frame memories, a video timing controller (VTC), two 256-word ×8-bit ×8-table Look Up Tables (LUTs) and 80 nsec/sampling A/D and D/A converters. This multiprocessor system performs convolution operations such as spatial filters, contrast enhancement, and binarization for gray-level images, thinning, thickening, pattern matching etc. for binary images, and image quality improvement for moving images such as T.V. images. Otherwise, it performs feature extraction operations such as area calculations, fillet coordination, and moment calculations for objective image data. Moreover, this system is capable of applying color image processing by using a multiboard system. 相似文献
55.
Takada K. Kitagawa T. Hattori K. Yamada M. Horiguchi M. Hickernell R.K. 《Electronics letters》1992,28(20):1889-1891
The group delay and dispersion, including the erbium ion contributions, of the highly erbium-doped silica planar waveguide amplifier and multicomponent glass fibre amplifiers are directly measured at different pump powers using a low coherence reflectometer and dispersive Fourier spectroscopy. This method derives the refractive index spectra of these amplifiers directly from the produced reflectograms without any physical or mathematical assumptions. The dispersion of the planar waveguide amplifier at 500 mW pumping changes between +300 and -200 ps/km/nm with a 0.4 wt.% erbium concentration.<> 相似文献
56.
Makoto Iida Masao Gotoh Hitoshi Yokono Yasushi Miyano 《Polymer Engineering and Science》1986,26(10):701-707
Flexural properties of moldings made by Reaction Injection Molding (RIM), which are structural foams consisting of high density skin and low density core, were investigated by three-point bending tests. Two failure modes were observed in bending tests of the moldings made by RIM, and they are classified as follows according to the density ratio of skin layer to core layer: the opposite side of the skin layer to which load was subjected failed by tensile stress: and the same side of the skin layer to which load was subjected failed by compressive stress, causing wrinkling or buckling. Then the conventional composite beam theory was applied to the former failure mode and Hoff s buckling theory to the latter, and equations were derived to predict the flexural properties of the structural foams, which involved buckling from the flexural properties of solid construction. In addition, it has been shown that there exists a density distribution that maximizes the flexural strength of the moldings made by RIM with a given overall density. The results obtained here should be useful to the optimum structural design of moldings made by RIM. 相似文献
57.
Various aspects of our communication are well known to have changed over time (1-3). This article describes a cross-sectional study that examined the acoustic characteristics of two groups of Australian women aged 18-25 years from recordings made in 1945 and 1993 and investigated the possible changes in the voice across generations. Archival recordings from 1945 which had been used in a longitudinal study (4) were compared to recordings made in 1993. The results of this study show that women in 1993 have significantly deeper voices than women of the same age recorded in 1945. The possible factors influencing this change are discussed. 相似文献
58.
T Matsuba M Yamada H Suzuki A Kanai O Isozaki T Yoshida T Tsushima K Yasukawa 《Canadian Metallurgical Quarterly》1995,118(2):265-270
Starting with a previously isolated cDNA for human thyrotropin receptor (TSHR), we established a transformed myeloma cell line, SP56, which expresses human TSHR on its cell surface. Binding analysis showed that SP56 bears 1.1 x 10(5) TSHR per cell with a Kd of 2.2 x 10(-10) M. Using the purified cellular membrane, we established a TSH binding inhibition immunoglobulin (TBII) assay for autoantibodies against TSHR. We compared it with the TBII assay utilizing porcine thyroid membranes expressing porcine TSHR, which has been widely used for TBII assay, by using 96 serum samples from patients with autoimmune thyroid disease and normal individuals. Our TBII assay was more sensitive than the one using porcine TSHR: of 38 sera of patients which were judged negative for autoantibodies to TSHR (TBII value below 10%) by the latter assay, 28 were positive (above 20%) in our assay. By using a perfusion culture system, we obtained as many as 3 x 10(10) SP56 cells, from which 3,450 mg protein of the membrane could be purified; this is sufficient for 15,000 assays. The results indicate that the membrane of the myeloma cell line SP56 is more suitable for use in the TBII assay than the porcine thyroid membrane, in terms of sensitivity to autoantibodies against TSHR in human sera. 相似文献
59.
D Shiokawa H Ohyama T Yamada K Takahashi S Tanuma 《Canadian Metallurgical Quarterly》1994,226(1):23-30
We studied total occlusion of all three coronary arteries. From 1975 to 1992, a total of 4,100 patients underwent coronary arteriography at Show University Hospital. Of these, four patients (0.1%) had complete occlusion of all three coronary arteries and all of them underwent coronary artery bypass grafting (CABG). The mean numbers of coronary risk factors were only 2.3 but history of angina of effort were long-standing such as 4 to 29 years (mean 16.3 yr). All cases had previous episodes of myocardial infarction. Three cases (75%) had aortic aneurysm. One case was also diagnosed as Leriche syndrome besides coexisting aneurysm. Coronary arteriogram showed total occlusion of right coronary artery, left anterior descending artery and left circumflex artery in the segment of 1.6 or 7 and 11 respectively. All cases had intracoronary anastomosis and intercoronary anastomosis. Among 12 occluded coronary arteries of all four cases, 11 were distally visualized with contrast medium via collateral flow but good opacification of the distal coronary trees were not seen. Also proper assessments of cardiac performance including viability of myocardium were not established because all cases were in the state of C.C.S grades IV. But significant clinical recovery were obtained in all cases after CAGB of three or four bypass. We conclude that these results might be a useful suggestion for the treatment of total occlusion of all three coronary arteries. 相似文献
60.
To determine whether miotic response to dilute (0.0625%, two drops) topical pilocarpine could be useful in detecting Alzheimer's disease (AD), we assessed the response in 14 AD patients and 10 control subjects. The miotic response to pilocarpine was significantly greater in AD patients than in control subjects (p < 0.001). In contrast, mydriatic response to the anticholinergic tropicamide (0.01%, one drop) failed to show a difference between the groups (p = 0.54). There was no significant correlation between the miotic and mydriatic responses in individuals. We conclude that dilute pilocarpine could be useful as a diagnostic tool in early AD. 相似文献