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61.
62.
Wakabayashi K Matsumura T Nakayama Y Koshi M 《The Review of scientific instruments》2011,82(2):026112
We performed miniature flyer impact experiments to investigate the relationship between the apparent (u(a)) and actual (u(A)) particle velocities measured by a velocity interferometer in single-crystal lithium fluoride (LiF) that was shock-compressed along the [100] axis. The miniature flyer was accelerated to velocities in the range 652.5-1937.6 m/s by a tabletop pulsed laser. An empirical relationship of u(a) = (1.2749 ± 0.0102)u(A) was obtained. The obtained relationship agreed well with the results of a previous study within the experimental errors and its uncertainty was less than ±1%. This result indicates that the present experimental technique is effective for measuring the relationship between u(a) and u(A) of shocked transparent materials with a comparable accuracy to conventional methods. 相似文献
63.
control with limited communication and message losses 总被引:2,自引:0,他引:2
We propose an H∞ approach to a remote control problem where the communication is constrained due to the use of a shared channel. The controller employs a periodic time sequencing scheme for message transmissions from multiple sensors and to multiple actuators of the system. It further takes into account the information on the random message losses that occur in the channel. An exact characterization for controller synthesis is obtained and is stated in terms of linear matrix inequalities. Furthermore, an analysis on the loss probabilities of the messages to accomplish stabilization is carried out. The results are illustrated through a numerical example. 相似文献
64.
Hideaki Adachi Toshifumi Satoh Masahiro Sakai Koichi Mizuno Kentaro Setsune 《Journal of Superconductivity》1994,7(4):737-741
Epitaxial multilayer thin films of infinite-layer (Sr, Ca)CuO2 and perovskite (Sr, Ca)RuO3 have been prepared on (100) SrTiO3 substrates by multitarget rf magnetron sputtering. X-ray diffraction analyses revealed that the multilayer structure of (Sr, Ca)CuO3/(Sr, Ca)RuO3 was successfully fabricated with a minimum layer thickness of 20 Å. Transmission electron microscopy measurements of the multilayers indicated that there was no dislocation which normally exists in single-layer films with an infinite-layer structure. Resistivities of multilayer films at room temperature ranged from 1 to 10 m cm and showed semiconductor-like dependence against the temperature. 相似文献
65.
Equilibria between CaO-TiOx or CaO-Al2O3-TiOx melts and liquid iron with respect to O, N and S were studied at 1873 K as a function of Ti (or Al) content in metal, using a CaO or an Al2O3 crucible. The Al-O and Ti-O relations in liquid iron were studied, and nitride and sulfide capacities defined by and , respectively, were obtained from nitrogen and sulfur distribution ratios, coupled with the analyzed oxygen content in liquid iron or the PO2 determined by Ti/TiO2 equilibrium. Based on these results, activities of Al2O3 and activity coefficients of TiO2 and TiO1.5 were evaluated. 相似文献
66.
T Kimura N Hatano M Wada K Iwata Y Kurosaki T Nakayama T Yamaura H Nakajima 《Canadian Metallurgical Quarterly》1995,18(11):1556-1559
The disposition of diadenosine 5'5"'-P1,P4-tetraphosphate (Ap4A), an endogenous dinucleotide, was investigated in rats. The degradation of Ap4A in rat plasma was very rapid and could be explained by a Michaelis-Menten equation: Km and Vmax values were 1.69 micrograms/ml and 4.32 micrograms/min/ml, respectively. Ap4A was degraded in rat plasma to ATP and AMP, but not to 2 ADP molecules, and these nucleotides were further degraded through adenosine. The degradations kinetics were examined. After intravenous bolus injection, Ap4A in plasma declined rapidly and the rate of elimination was dose-dependent: the biological half-life was about 3s at the dose of 1 mg/kg and was longer at 3 mg/kg. When Ap4A was administered by intravenous infusion (0.5 or 1.0 mg/kg/min), the plasma level rapidly reached a steady-state, which then rapidly declined after stopping the infusion. 相似文献
67.
We consider the average consensus problem for the multi-agent system in the discrete-time domain. Three triggering based control protocols are developed, which dictate the broadcast and control update instants of individual agents to alleviate communication and computational burden. Lyapunov-based design methods prescribe when agents should communicate and update their control so that the network converges to the average of agents' initial states. We start with a static version of the distributed event-triggering law and then generalize it so that it involves an internal auxiliary variable to regulate the threshold dynamically for each agent. The third protocol uses a self-triggering algorithm to avoid continuous listening wherein each agent estimates its next triggering time and broadcasts it to its neighbors at the current triggering time. Numerical simulations are shown to validate the efficacy of the proposed algorithms. 相似文献
68.
69.
S Nakamura S Shibata K Shirota K Abe K Uetsuka H Nakayama N Goto K Doi 《Canadian Metallurgical Quarterly》1996,33(6):696-699
Renal glomerular fibrosis was observed in a 1-year-old spayed female Japanese domestic cat that showed clinically advanced renal failure. In the glomeruli, increased homogeneous materials were stained strongly with aniline blue by Masson's trichrome and positive for anti-type III collagen antibody by immunohistochemical staining, causing mesangial sclerosis and capillary collapse. By electron microscopy, randomly arranged fibrils were observed in the expanded subendothelial and mesangial areas, and the fibrils showed periodicity characteristic of collagen fibers in longitudinal sections. These findings of glomerular lesions closely resemble those of human "collagenofibrotic glomerulonephropathy," which has recently been described as a new type of glomerulonephropathy. 相似文献
70.
Using mullite (3Al2O3·2SiO2)-tube type and ZrO2 (MgO mole fractions of 9 %)-plug type solid electrolyte, the activities of Al in the Fe-15, 29% Ni-0.002 to 0.84% Al (mass contents in%) alloys were measured at 1873 K in an Al2O3 crucible, and those of Si in the Fe-13, 28% Ni-0.13 to 2.3% Si alloys were measured at 1823 K in a mullite crucible with an excess of SiO2. The interaction coefficients of and were determined as ?0.0173 ± 0.0052 and 0.00021 ± 0.00007, respectively, and those of and were determined as 0.0094 ± 0.0049 and ?0.00008 ± 0.00004, respectively. The oxygen activities obtained by the EMF measurements were compared with those obtained from the contents of analyzed oxygen. The oxygen activities in the Fe-Ni-Al alloys were found to be supersaturated. The interaction coefficients of and were determined as 0.0027 ± 0.0012 and 0.00012 ± 0.00004, respectively, from the contents of analyzed oxygen in Fe-Ni-Si alloys. 相似文献