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排序方式: 共有904条查询结果,搜索用时 15 毫秒
91.
Bae J. Nozokido T. Shirai H. Furuya K. Nishida T. Mizuno K. 《Quantum Electronics, IEEE Journal of》1989,25(7):1591-1594
A modified current pulsed Q (EMQ)-switched CO2 laser which is Q -switched by a mechanical beam chopper in combination with a pulsed discharge current is discussed. The laser produces a very stable output with a peak power greater than 1 kW at a repetition rate of 1000 p.p.s. for all transitions in the P and R branches of the CO2 spectrum. A CH3F laser pumped by the EMQ-switched laser produces 496 μm radiation in a 6.5 W peak, 100 ns pulses at 500 p.p.s. in the lowest loss EH11 mode 相似文献
92.
K Takeshita S Furui S Ban A Harasawa H Kohtake T Yamauchi Y Sasaki T Shirai Y Kikuchi 《Canadian Metallurgical Quarterly》1996,56(11):744-746
Helical computed tomography was performed with intravenous contrast material administration in ten patients with hepatic tumors (metastatic tumor, n = 6; hepatocellular carcinoma, n = 4). Maximum intensity projection (MIP) images of intrahepatic portal venous branches and hepatic veins, and shaded surface display (SSD) images of the hepatic tumors were reconstructed for each patient. The MIP image and SSD image were fitted to overlap on a single display to obtain three-dimensional (3-D) images showing both the hepatic vessels and hepatic tumors. Subsegmental localization of the tumors determined from the 3-D images proved to be correct in all of the six patients who received hepatic resection after examination. 3-D images seem to be useful for preoperative assessment of hepatic tumors. 相似文献
93.
T Fujimura S Hirose Y Jiang S Kodera H Ohmuro D Zhang Y Hamano H Ishida S Furukawa T Shirai 《Canadian Metallurgical Quarterly》1998,10(10):1467-1472
Gene(s) in the MHC of the NZW strain (H-2z) up-regulate(s) systemic lupus erythematosus (SLE) in (NZB x NZW) F1 mice. So far, two plausible mechanisms have been implicated: (i) unique mixed haplotype class II molecules formed in the F1 mice act as a restriction element for self-reactive T cells and (ii) a unique polymorphism in the H-2-linked NZW tumor necrosis factor (TNF)-alpha allele which down-regulates TNF-alpha is contributory. Because of the difficulty in dissecting these alleles within the H-2 complex, it has not been determined which is indeed the case. We addressed this issue by establishing three different H-2-congenic (NZB x NZW) F1 mice bearing distinct haplotypes at class II and TNF-alpha regions, i.e. (NZB x NZW) F1 (H-2d/z:A(d/u)E(d/u)TNF(d/z)), (NZB x NZW.PL) F1 (H-2(d/u):A(d/u)E(d/u)TNF(d/d)) and (NZB x NZW.H-2d) F1 (H-2(d/d):A(d/d)E(d/d)TNF(d/d)). Among these, only (NZB x NZW) F1 produced a markedly lower level of TNF-alpha, due to the unique NZW TNF-alpha allele (TNF(z)). Studies of anti-DNA antibodies and lupus nephritis revealed that, compared to (NZB x NZW) F1, the disease of (NZB x NZW.H-2d) F1 was markedly reduced. In (NZB x NZW.PL) F1, the onset of renal disease was significantly delayed, while the extent of proteinuria and renal histopathology in individuals that had developed the disease was comparable to that seen in (NZB x NZW) F1. It seems likely that both class II and TNF-alpha gene polymorphisms are functioning as H-2-linked predisposing genetic elements, and that the TNF-alpha polymorphism acts to modulate an initial process of the renal disease. 相似文献
94.
Yoshishige Kemmoku Keiko Ishikawa Shigeyasu Nakagawa Teru Kawamoto Tateki Sakakibara 《Electrical Engineering in Japan》2002,138(2):14-23
A photovoltaic/wind/diesel generating system with a battery (PWD system) is discussed from the viewpoint of total CO2 gas emissions during system lifetime. The total emissions are the sum of the emissions occurring at manufacturing and operating. First, the manufacturing CO2 emissions of the photovoltaic generator and the wind turbine generator are calculated by “the process analysis method.” This method considers the material used in each generator, its weight and its CO2 emission rate. On the other hand, the manufacturing CO2 emissions of the diesel generator and the battery are calculated using “the interindustry (input‐output) table.” Second, the PWD system is operated on a computer so that the fuel consumption of the diesel generator is a minimum assuming that hourly series data of electric load, insolation intensity, wind speed, and air temperature are known during the year. And CO2 emissions occurring at system operation are obtained from the annual fuel consumption of the diesel generator. The results show that CO2 total emissions of the PWD system are lower than those of the conventional diesel generator system. The CO2 total emissions reach a minimum when the photovoltaic/wind generating ratio is 50/50. The CO2 emissions of manufacturing decrease with increasing of the wind generating ratio from 100/0 to 0/100. The CO2 total emissions decrease as the natural energy ratio increases. It is, however, saturated to about 60% when the ratio is more than 60%. And the CO2 total emissions increase with increasing of the battery capacity. It is concluded that the PWD system plays an important role in decreasing considerably the CO2 total emissions while the total system cost is high under the present price circumstances. © 2001 Scripta Technica, Electr Eng Jpn, 138(2): 14–23, 2002 相似文献
95.
Lumisight Table: an interactive view-dependent tabletop display 总被引:1,自引:0,他引:1
Kakehi Y. Iida M. Naemura T. Shirai Y. Matsushita M. Ohguro T. 《Computer Graphics and Applications, IEEE》2005,25(1):48-53
A novel tabletop display provides different images to different users surrounding the system. It can also capture users' gestures and physical objects on the tabletop. The Lumisight Table approach is based on the optical design of a special screen system composed of a building material called Lumisty and a Fresnel lens. The system combines these films and a lens with four projectors to display four different images, one for each user's view. In addition, we need appropriate input methods for this display media. In the current state of the project, we can control computers by placing physical objects on the display or placing our hands over the display. This screen system also makes it possible to use a camera to capture the appearance of the tabletop from inside of the system. Our other main idea is to develop attractive and specialized applications on the Lumisight Table, including games and applications for computer-supported cooperative-work (CSCW) environments. The projected images can be completely different from each other, or partially identical and partially different. Users can share the identical parts as public information, because all users can see it. This article is available with a short video documentary on CD-ROM. 相似文献
96.
Shirai M. Arimoto H. Watanabe K. Taike A. Shinoda K. Shimizu J. Sato H. Ido T. Tsuchiya T. Aoki M. Tsuji S. Sasada N. Tada S. Okayasu M. 《Electronics letters》2003,39(9):733-735
A novel travelling-wave electroabsorption optical modulator, electrically matched for 50 /spl Omega/ loads of driving circuit drivers, was developed. The scattering parameter of electric reflection (S/sub 11/) from this modulator is less than -20 dB at 20 GHz. It can thus enable a 40 Gbit/s, 2 km SMF transmission with a 0.3 dB penalty at a 1.3 /spl mu/m wavelength. 相似文献
97.
Experiment and numerical simulation of double-layered RC plates under impact loadings 总被引:1,自引:0,他引:1
Tetsuo Shirai Atsushi Kambayashi Tomonori Ohno Hajime Taniguchi Masatoshi Ueda Nobutaka Ishikawa 《Nuclear Engineering and Design》1997,176(3)
This paper is to investigate and to propose a method to improve the impact resistance of reinforced concrete (RC) plates against projectile impact, and the damage of double-layered RC plates is examined experimentally and simulated analytically. In tests, a projectile launching apparatus, which is a 40 mm smooth-bore airgun, was used. Based on experimental results, numerical simulations with the DYNA-3D code, which takes account of the dynamic constitutive law of concrete, were done to find the applicability of the present computer code to the analysis of double-layered RC plates under high-speed impact loadings. In this study, the impact resistance of concrete plate is defined as the degree of local damage. In both experiments and numerical simulations, the effect of double-layering on the impact resistance is discussed. 相似文献
98.
Takeyuki Suzuki Yoshitaka Dansui Tetsuji Shirai Chikako Tsubaki 《Journal of Materials Science》1985,20(9):3125-3130
The solid solubility limit, grain orientation, defect structure and electrical conductivity of solidified rhombohedral specimens
in the Bi2O3-BaO system are described. The c-axes (in hexagonal notation) of solidified specimens were almost entirely oriented along the platelet/film thickness. Slow-cooling
(∼ 10−2° Csec−1) of the system gave solid solutions with substitutional type of 2BaO → 2BaBi′ + 20+ V
0
..
for 12 to 32 mol % BaO. High-temperature modification of slowly-cooled sample (16 mol % BaO) showed a conductivity of 8.8×10−1 Ω−1 cm −1 at 600° C along the conduction plane (perpendicular to the c-axis). Rapid quenching (∼ 105° C sec−1) produced solid solutions for 8 to 20 mol % BaO introducing interstitial Ba2+ (10–12 mol % BaO) and Schottky type defects such as VBi‴ and V
Bi
‴
and V
0
..
(16 to 20 mol % BaO), however the high-temperature modification of the rhombohedral structure could not be frozen. 相似文献
99.
S Nishida K Kuroko T Hoshino T Iwamoto C Shirai 《Canadian Metallurgical Quarterly》1998,44(8):599-601
There are few reports of the sonographic appearance of Meckel's diverticulum. We present a case of torsion of a Meckel's diverticulum that was suggested by sonography and confirmed pathologically. We discuss the sonographic differential diagnosis, which includes acute appendicitis, enteric duplication cyst and intestinal volvulus. 相似文献
100.