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排序方式: 共有758条查询结果,搜索用时 93 毫秒
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Nakano Hirofumi Ishizaka Kazuhisa Obata Motoki Kimura Keiji Kasahara Hironori 《International journal of parallel programming》2003,31(3):211-223
Effective use of cache memory is getting more important with increasing gap between the processor speed and memory access speed. Also, use of multigrain parallelism is getting more important to improve effective performance beyond the limitation of loop iteration level parallelism. Considering these factors, this paper proposes a coarse grain task static scheduling scheme considering cache optimization. The proposed scheme schedules coarse grain tasks to threads so that shared data among coarse grain tasks can be passed via cache after task and data decomposition considering cache size at compile time. It is implemented on OSCAR Fortran multigrain parallelizing compiler and evaluated on Sun Ultra80 four-processor SMP workstation using Swim and Tomcatv from the SPEC fp 95. As the results, the proposed scheme gives us 4.56 times speedup for Swim and 2.37 times on 4 processors for Tomcatv respectively against the Sun Forte HPC Ver. 6 update 1 loop parallelizing compiler. 相似文献
23.
The use of a sodium film as a filter for wavelengths between 40 and 80 nm is discussed, and a technique to prepare these films is described. Sodium films of 230 nm thickness were demonstrated to have a transmission of 55% at 100 degrees K at a wavelength 41 nm. The transmission decreased to 40% after 18 h in a vacuum of 5x10(-8) Torr. Films of this thickness were shown to attenuate 20.5-nm radiation appearing in second order at 41 nm by at least a factor of 50. 相似文献
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Sang-Jae Yoon Dingding Chen Ja-Uk Gu Nak-Sam Choi Kazuo Arakawa 《International Journal of Fracture》2014,187(1):173-178
A method is described to characterize the uniformity of interlaminar fracture toughness of laminated carbon-fiber-reinforced polymer (CFRP) composites fabricated by the modified vacuum assisted resin transfer molding process. To prepare specimens for Mode I fracture toughness tests, pieces were sectioned from the inlet and vent regions of a CFRP plate ([+30/-30]6), with a starter crack inserted. The specimens were packed between two rectangular epoxy plates to apply a load using a universal testing machine. Acoustic energy signals were monitored using two sensors attached to the epoxy plates during tensile loading. The difference between the material properties of specimens from the inlet and vent regions of the CFRP plate were statistically compared using one-way analysis of variance (ANOVA); we show that the specimens showed no statistically significant differences in the interlaminar fracture characteristics depending on the part of the mold from which they were taken. 相似文献
27.
We prepared relatively uniform supported Ru catalysts by ion‐exchange and CVD methods, using an NaY zeolite and a mesoporous
FSM‐16 as substrates, and carried out CO2 hydrogenation. They showed high activity for CO2 hydrogenation. A Ru‐ion‐exchanged catalyst showed high activity for methanol production. Co addition promoted methanol formation.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
28.
K. Hara T. Horiguchi T. Kinoshita K. Sayama H. Arakawa 《Solar Energy Materials & Solar Cells》2001,70(2)
We have studied the influence of electrolytes on the photovoltaic performance of mercurochrome-sensitized nanocrystalline TiO2 solar cells using LiI, LiBr, and tetraalkylammonium iodides as the electrolyte. Short-circuit photocurrent density (Jsc) and open-circuit photovoltage (Voc) depended strongly on the electrolyte. Jsc of 3.42 mA cm−2 and Voc of 0.52 V were obtained for the LiI electrolyte and Jsc of 2.10 mA cm−2 and Voc of 0.86 V were obtained for the Pr4NI electrolyte. This difference in photovoltaic performance was due to the change in the conduction band level of the TiO2 electrode. Large Voc of 0.99 V was obtained for the LiBr electrolyte due to the large energy gap between the conduction band level of TiO2 and the Br/Br2 redox potential. Solar cell performance also depended strongly on organic solvent, suggesting that the physical properties of solvents such as Li ion conductivity and donor number affect photovoltaic performance. 相似文献
29.
Toughening of Silicon Nitride Matrix Composites by the Addition of Both Silicon Carbide Whiskers and Silicon Carbide Particles 总被引:1,自引:0,他引:1
Hironori Kodama Takaaki Suzuki Hiroshi Sakamoto Tadahiko Miyoshi 《Journal of the American Ceramic Society》1990,73(3):678-683
Si3 N4 matrix composites reinforced by SiC whiskers, SiC particles, or both were fabricated using the hot-pressing technique. The mechanical properties of the composites containing various amounts of these SiC reinforcing materials and different sizes of SiC particles were investigated. Fracture toughness of the composites was significantly improved by introducing SiC whiskers and particles together, compared with that obtained by adding SiC whiskers or SiC particles alone. On increasing the size of the added SiC particles, the fracture toughness of the composites reinforced by both whiskers and particles was increased. Their fracture toughness also showed a strong dependence on the amount of SiC particles (average size 40 μm) and was a maximum at the particle content of 10 vol%. The maximum fracture toughness of these composites was 10.5 MPa·m1/2 and the flexural strength was 550 MPa after addition of 20 vol% of SiC whiskers and 10 vol% of SiC particles having an average particle size of 40 μm. These mechanical properties were almost constant from room temperature to temperatures around 1000°C. Fracture surface observations revealed that the reinforcing mechanisms acting in these composites were crack deflection and crack branching by SiC particles and pullout of SiC whiskers. 相似文献
30.
Koji Ouchi Shoichi Ibaragi Ataru Kobayashi Kazuyuki Tanimoto Masataka Makabe Hironori Itoh Kenji Matsubara Tomei Takekawa 《Fuel》1984,63(1):78-83
After solvent extraction of Taiheiyo, Miike and Balmer coals using wash oil under nitrogen atmosphere at 370 °C for 30 min, the extraction yield is always within the additivity law. Further studies used Yallourn, Soyakoishi, Taiheiyo, Horonai, Miike, Shin Yubari, Balmer coals and their blends which were hydrogenated in tetralin, wash oil or creosote oil, with or without catalyst, at 400–450 °C under 10 or 3 MPa of initial hydrogen pressure. When hydrogen is available, the additivity law exists for blended coals, but when the hydrogen supply is deficient, the experimental conversion of blended coals is always lower than calculated conversions. This may be due to the faster consumption of the hydrogen by more reactive coals and thus the less reactive coals were unable to react with hydrogen. 相似文献