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991.
Element-free Galerkin method using directed graph and its application to creep problems 总被引:1,自引:0,他引:1
The element-free Galerkin method (EFGM) is one of the meshless methods proposed by Belytschko et al. Since node-element connectivities used in the finite element method (FEM) are not needed in the EFGM, the EFGM is expected to be applied to many problems of the continuum mechanics and to be utilized for a tool in a CAE system instead of the FEM. However the EFGM requires more CPU time to search nodes of the MLSM than the FEM. In this paper, the method of the directed graph and the Delaunay triangulation are respectively used for searching nodes and the division of the integral domain respectively. These techniques are useful for saving the CPU time and the simplification of the analysis for the EFGM. Furthermore, the EFGM has not been applied to nonlinear problems such as creep problems under elevated temperature. In this paper, the EFGM using the method of the directed graph and the Delaunay triangulation is applied to several creep problems. The CPU times for the analyses are reduced by the proposed EFGM. The results obtained from the EFGM analyses agree well with those of the FEM. 相似文献
992.
993.
K. Ioki M. Shimada M. Nagami M. Maeno S. Izumi H. Yokomizo H. Yoshida K. Shinya N. Brooks R. Seraydarian T. Taylor T. McMahon A. Kitsunezaki 《Nuclear Engineering and Design》1982,73(1)
Using a single null divertor configuration, heat flux intensity and its profile on the divertor plates as a function of plasma current and density were measured with an infrared camera and thermocouples. The vertical width of the heat flux on the divertor plates 2λ is ≈ 10 cm at the lower separatrix and is ≈ 5.5 cm at the upper separatrix. A diffusion coefficient D which is obtained from the measurement of the diffusion length across the scrape-off field lines is roughly proportional to
and its magnitude is on the order of Bohm diffusion. The heat flux on the plates decreases by more than a factor of 5 with increasing electron density in the main plasma and is much smaller than that on the limiters in non-diverted plasmas. Only 3% of ohmic input power goes into the divertor plates at high density of the main plasma, while ≈ 20% goes in at low density. The decrease of heat flux is in good agreement with the increase of radiation loss in the divertor region. The heat flux on the divertor plates can be reduced by remote radiative cooling in high density discharges. 相似文献
994.
995.
996.
Sawata Shinya Y.; Taira Kazunari 《Protein engineering, design & selection : PEDS》2003,16(12):1115-1124
The ribosome display system is a very effective and powerfultool for in vitro screening of transcribed mRNAs that encodeproteins (or peptides) with specific (known or unknown) functions.The system depends on the stability of ribosomemRNA complexesthat have been formed as a result of the removal of a stop codon.To assess the general applicability of the system, we examinedthe stability of ribosomemRNA complexes in the presenceand absence of a stop codon, as well as in the presence andthe absence of an additional interaction between the translatedpeptide and its mRNA within the ribosomemRNA complex.The additional interaction that we exploited was the interactionbetween a tandemly fused MS2 coat-protein (MSp) dimer and theRNA sequence of the corresponding specific binding motif, C-variant(Cv). The MSp dimer and Cv were placed, respectively, at theN-terminal end of a nascent protein, translated in vitro, andat the 5' end of the proteins mRNA, and consequentlyfurther stabilize the ribosomemRNA complex. To our surprise,we were able to select proteins even in the presence of a stopcodon. Moreover, as we had anticipated, the interaction betweenthe MSp dimer and Cv enhanced the stability of the ribosomemRNAcomplex, suggesting that this kind of interaction might be usefulin the design of an efficient ribosome display selection strategy.Indeed, the yield of the mRNAs of interest after selection wasincreased upon the introduction of the interaction between theMSp dimer and Cv. Received June 20, 2003; revised October 2, 2003; accepted October 6, 2003 相似文献
997.
S Takahashi S Tamano M Hirose N Kimoto Y Ikeda M Sakakibara M Tada FF Kadlubar N Ito T Shirai 《Canadian Metallurgical Quarterly》1998,58(19):4307-4313
A polyclonal antibody against 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP)-DNA adducts was raised for their immunohistochemical demonstration in paraffin-embedded sections. Specificity of this antibody was confirmed by competitive ELISA. Positive signals were immunohistochemically detected in acetone-fixed but not in formalin- or ethanol-fixed sections from F344 rats treated by gavage with a single dose of PhIP at 37.5-300 mg/kg and killed at 1, 2, and 7 days thereafter. Dose-dependent positive staining was observed in almost all organs of both sexes, including the colon, prostate, and mammary gland but largely independent of the tumor response. Repair activity, judged by disappearance of adducts with time, differed according to the organ or cell type. One exception was hepatocytes, the liver incidentally being a nontarget organ. The results suggest that the generated antibody is applicable for detection of cells targeted by PhIP in paraffin-embedded sections and also for the investigation of the mechanisms of PhIP-carcinogenesis. 相似文献
998.
Heterojunction switching photodiodes (InGaAs/InP) were used to construct a 3×3 matrix switch. Isolation and cross-talk losses were better than 63 dB over a frequency range of 10 Hz to 400 MHz and 400 Mbit/s digital signals were switched with switching times shorter than 30 ns. 相似文献
999.
A decentralized control scheme is given for the stabilization of large-scale linear systems composed of a number of controllable subsystems. A class of interconnection structures among subsystems is defined for which the overall system can always be stabilized by local state feedback which is optimal for a quadratic performance index. The resulting closed-loop system has robust stability properties against a wide range of variations in open-loop dynamics. Optimality of the decentralized control law is preserved for a modified performance index under perturbations in interconnections such that the strength of coupling does not increase. The class of decentrally stabilizable large-scale systems presented in this paper is the largest such class hitherto described by the structure of interconnections. 相似文献
1000.
T. Haseyama T. Arai A. Fukuda H. Funahashi S. Ikeda K. Imai Y. Isozumi T. Kato Y. Kido A. Matsubara S. Matsuki T. Mizusaki T. Nishimura D. Ohsawa A. Sawada Y. Takahashi M. Tosaki K. Yamamoto 《Journal of Low Temperature Physics》2008,150(3-4):549-554
A high-sensitivity microwave-single-photon detector was developed in Kyoto, in which microwave photons in a resonant cavity
cooled at very low temperatures are absorbed by highly excited Rydberg atoms and the Rydberg atoms thereby promoted to a higher
excited state are then selectively field-ionized and detected. This scheme allows us to count microwave photons one by one,
thus provide a single-photon counting without the limit of standard quantum limit (SQL). The apparatus “CARRACK” for the single-photon
detector was constructed based on this scheme, where the cavity was cooled down to 10 mK range to reduce the background of
thermal blackbody photons from the cavity wall. The apparatus has served for years to search for dark matter axions in the
10 μeV (∼2.4 GHz) mass region. Thermal blackbody photons in a microwave resonant cavity at temperatures as low as 70 mK have
been measured, the sensitivity being below the SQL limit. A number of improvements in the detection efficiency and sensitivity
have been planned and will be reported. Applications of the detector to fundamental physics are also discussed shortly.
相似文献