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61.
We present a new architecture level unified reliability evaluation methodology for chip multiprocessors (CMPs). The proposed reliability estimation (REST) is based on a Monte Carlo algorithm. What distinguishes REST from the previous work is that both the computational and communication components are considered in a unified manner to compute the reliability of the CMP. We utilize REST tool to develop a new dynamic reliability management (DRM) scheme to address time-dependent dielectric breakdown and negative-bias temperature instability aging mechanisms in network-on-chip (NoC) based CMPs. Designed as a control loop, the proposed DRM scheme uses an effective neural network based reliability estimation module. The neural-network predictor is trained using the REST tool. We investigate how system’s lifetime changes when the NoC as the communication unit of the CMP is considered or not during the reliability evaluation process and find that differences can be as high as 60%. Full-system based simulations using a customized GEM5 simulator show that reliability can be improved by up to 52% using the proposed DRM scheme in a best-effort scenario with 2–9% performance penalty (using a user set target lifetime of 7 years) over the case when no DRM is employed. 相似文献
62.
Toshihiro Nagao Yuji Shimada Yoshie Yamauchi-Sato Takaya Yamamoto Masaaki Kasai Kentaro Tsutsumi Akio Sugihara Yoshio Tominaga 《Journal of the American Oil Chemists' Society》2002,79(3):303-308
A commercial product of CLA contains almost equal amounts of cis-9,trans-11 (c9,t11)-CLA and trans-10,cis-12 (t10,c12)-CLA. We attempted to enrich the two isomers by a two-step selective esterification using Candida rugosa lipase that acted on c9,t11-CLA more strongly than on t10,c12-CLA. An FFA mixture containing CLA isomers was esterified with an equimolar amount of lauryl alcohol in a mixture of 20%
water and the lipase. When the esterification of total FA reached 50%, two isomers were fractionated in a good yield: t10,c12-CLA was enriched in FFA, and c9,t11-CLA was recovered in lauryl esters. The FFA were esterified again to enrich t10,c12-CLA. At 27.3% esterification of total FA, the t10,c12-CLA content in FFA increased to 64.8 wt% with 89.3% recovery: The ratio of the content of t10,c12-CLA to that of two isomers was 95.9%. Lauryl esters obtained by the single esterification were employed for enrichment
of c9,t11-CLA. After the esters were hydrolyzed, the resulting FFA were esterified again with lauryl alcohol. At 62.0% esterification
of total FA, the c9,t11-CLA content in lauryl esters increased to 73.3 wt% with 79.4% recovery: The ratio of the content of c9,t11-CLA to that of two isomers was 95.6%. In a 600-g-scale purification, molecular distillation was effective in separating
the reaction mixture into lauryl alcohol, FFA, and lauryl ester fractions. 相似文献
63.
Effect of vanadium and chromium on the microstructural features of V–Cr–Mn–Ni spheroidal carbide cast irons 总被引:2,自引:0,他引:2
V.G.Efremenko ;K.Shimizu ;A.P.Cheiliakh ;T.V.Kozarevskaya ;K.Kusumoto ;K.Yamamoto 《北京科技大学学报(英文版)》2014,(11):1096-1108
The objective of this investigation is to study the influence of vanadium(5.0wt%–10.0wt%) and chromium(0–9.0wt%) on the microstructure and hardness of Cr-V-Mn-Ni white cast irons with spheroidal vanadium carbides. The alloys' microstructural features are presented and discussed with regard to the distribution of phase elements. The structural constituents of the alloys are spheroidal VC, proeutectoid cementite, ledeburite eutectic, rosette-shaped carbide eutectic(based on M7C3), pearlite, martensite, and austenite. Their combinations and area fraction(AF) ratios are reported to be influenced by the alloys' chemical composition. Spheroidized VC particles are found to be sites for the nucleation of carbide eutectics. Cr and V are shown to substitute each other in the VC and M7C3 carbides, respectively. Chromium alloying leads to the formation of a eutectic(γ-Fe + М7С3), preventing the appearance of proeutectoid cementite in the structure. Vanadium and chromium are revealed to increase the total carbide fraction and the amount of austenite in the matrix. Cr is observed to play a key role in controlling the metallic matrix microstructure. 相似文献
64.
Lingyun Lyu Takeshi Hanada Naohiro Yamahira Jun Morita Ryota Yamamoto Ken Itomi Takumi Adachi Sho Kubouchi Shin Horiuchi 《应用聚合物科学杂志》2021,138(45):51443
The distribution of nano-sized silica in binary rubber blends is characterized by scanning transmission electron microscopy (STEM) tomography combined with energy dispersive X-ray spectrometry (EDX). 3D distribution of silica is visualized by STEM-EDX tomography with the tilt-series of silicon elemental maps, while the phase-separated morphologies of polyisoprene rubber (IR) and styrene-butadiene rubber (SBR) are visualized by STEM-tomography in high-angle-annular-dark field (HAADF) mode. The combination of STEM-EDX and STEM-HAADF tomography enables us to determine the distribution of silica between the two rubber phases quantitatively even with high contents of silica up to 70 phr (weight parts per hundred rubber). It is found that silica is preferentially distributed in the SBR phase, but it is also distributed in the IR phase when the IR fraction in the total rubber components is higher than 40 wt%. The preferential distribution of silica in the SBR phase improves the dispersion of the IR domains. This is the first use of this technique for a multicomponent polymer system, showing the advantage to characterize the complicated multicomponent polymer composite morphologies. 相似文献
65.
An interferometric technique for automated profilometry of diffuse objects has been proposed. It is based on the Fourier-fringe analysis of spatiotemporal specklegrams produced by a wavelength-shift interferometer with a laser diode as a frequency-tunable light source. Unlike conventional moiré techniques the proposed technique permits the objects to have discontinuous height steps and/or surfaces spatially isolated from one another. Experimental results are presented that demonstrate the validity of the principle. 相似文献
66.
Hikaru Yamamoto 《Journal of Low Temperature Physics》1994,94(1-2):77-97
We have considered the behavior of the conductivity or the dielectric function of the one-dimensional (1-D) quantum sine-Gordon system (g2 = 4) for two models of impurities. We have used a Fermi-Bose relation and a self consistent t-matrix approximation. As for the conductivity at zero temperature, it appears when the concentration of impurities becomes larger than the critical concentration of impurities. It shows the linear increase near the critical concentration. As for the dielectric constant, its behavior is model dependent. We have numerically calculated the frequency dependence of the conductivity at zero temperature. The real part shows the second order increase near the critical frequency. The imaginary part shows the linear decrease from the origin. 相似文献
67.
The optical behavior of a thin film, that is, peak positions and intensities, is discussed for transmission under a thin-film approximation. The infrared transmission spectra of thin films, both standing films and those on dielectric substrates, are simulated for s and p polarization at various angles of incidence. For spectral simulation, the matrix method is used in conjunction with noise-free complex refractive indices based on the dispersion theory. The peak positions in the simulated spectra are compared with transverse optic and longitudinal optic frequencies based on the macroscopic theory. The simulated peak intensities for the standing films are compared with the prediction based on the thin-film approximation. Furthermore, it is found from the spectral simulation for thin films on dielectric substrates that the peak intensity for a thin film may depend on the thickness and refractive index of the substrate. 相似文献
68.
We report experimental results on enhanced backscattering from a plane mirror that is viewed through polymer-film-dispersed nematic liquid crystals. The distribution of the averaged intensity of the light reflected from the mirror placed behind the polymer film is investigated with an image-processing system when a Gaussian beam wave is incident. The enhanced light peak is observed in an incident beam direction, the result of which is predicted by a theory based on the circular Gaussian statistic random-phase-screen model. We pay attention to the enhancement dependence on parameters such as the distance between the polymer film and the flat mirror. The observed result is similar to a previous study by Jakeman et al. in which a random diffusive glass plate was used as a random-phase screen [J. Phys. D 21, 32 (1988)]. 相似文献
69.
Yuichi Ogawa Nobuyuki Inoue Jifang Wang Takashi Yamamoto Kunihiko Okano 《Journal of Fusion Energy》1995,14(4):353-359
Based on scientific databases adopted for designing ITER plasmas and on the advancement of fusion nuclear technology from the recent R&D program, a low wall-loading DEMO fusion reactor has been designed, where high priority has been given to the early and reliable realization of a tokamak fusion plasma over the cost performance. Since the major radius of this DEMO reactor is chosen to be 10 m, plasma ignition is achievable with a low fusion power of 0.8 GW and an operation period of 4–5 hours is available only with inductive current drive. The low ignition power makes it possible to adopt a first wall with an austenitic stainless steel, for which significant databases and operating experience exists, due to its use in the presence of neutron irradiation in fission reactors. In step with development of advanced materials, a step-wise increase of the fusion power seems to be feasible and realistic, because this DEMO reactor has the potential to produce a fusion power of 5 GW. 相似文献
70.
K Araki H Yamamoto M Kobayashi K Matsuura T Ogata 《Canadian Metallurgical Quarterly》1995,22(11):1531-1534
An intensive chemotherapy combined with surgery, termed "intraoperative local infusion chemotherapy (ILIC)", was devised. The ILIC procedure is to infuse 50 mg of cisplatin through the feeding artery to the tumor, which has been isolated from blood flow by clamping the stomach and blood vessels, before radical surgery. An experiment in dogs showed considerable free Pt transfer into thoracic lymph after ILIC. Sum total Pt in the thoracic lymph after ILIC (294.5 micrograms/3 h) was 4.3 times that after IV administration (68.3 micrograms/3 h). In ILIC, AUC of free Pt in the thoracic lymph was about 5.8 times that in peripheral blood. ILIC was applied in 24 advanced gastric cancer patients, consisting of 6, 2, 4 and 12 in pTNM stage II, IIIA, IIIB and IV, respectively. Pt concentration of the tissues was high in the tumor (23.22 micrograms/g) and the regional lymph nodes (2.95 micrograms/g) compared to that in the serum (0.45 microgram/ml). The survival rate (Kaplan-Meier) in the ILIC patients was significantly higher than that of control patients (matched pair method) from among patients treated by surgery alone. No fatal complications were encountered in any patient treated by ILIC. 相似文献