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61.
In this paper we propose an active circuit consisting of two capacitive double-layer uniformly distributed RC lines and an operational amplifier, and present conditions under which the circuit works as the low-pass filter. Furthermore, we present a method for designing the low-pass filter and give a design example where simulation results are included. 相似文献
62.
Extensive creep cavitation in Ti, Nb and Cu containing precipitation hardened austenitic steels was found to limit the usefulness of deformation resistance to increase long-term creep rupture strength. The steels were microalloyed with boron and cerium that resulted in increase in creep rupture strength and ductility of the steels significantly. Grain boundary sliding and creep cavity nucleation and growth in the steels were suppressed greatly on microalloying. Auger spectroscopic analysis revealed the segregation of boron instead of sulfur on cavity surface and the absence of sulfur contamination of grain boundary upon the microalloying. Suppression of creep cavitation through the control of trace elements segregation along with the precipitation hardening increased the creep rupture strength of austenitic stainless steels. 相似文献
63.
Ito M. Nitta K. Ohno K. Saigusa M. Nishida M. Yoshioka S. Irita T. Koike T. Kamei T. Komuro T. Hattori T. Arai Y. Kodama Y. 《Solid-State Circuits, IEEE Journal of》2009,44(1):83-89
Supporting both WCDMA with HSDPA and GSM/GPRS/EDGE, the 9.3 times 9.3 mm2 SoC fabricated in triple-Vth 65 nm CMOS, has three CPU cores and 20 separate power domains. Unused power domains can be powered down to reduce the leakage power. Partial clock activation scheme especially focused on music playback scene dynamically stops a PLL and clock trees when not necessary and reduces power consumption from 33.6 mW to 19.6 mW. IP-MMU translates virtual address to physical address for 18 hardware-IPs and virtual address space can be allocated when necessary and can be freed after its operation, reducing external memory by 43 MB. Video performance of D1 (720 times 520) size with 30 frames per second for MPEG/AVC decoding and encoding can be achieved under mixed virtual and physical address usage. 相似文献
64.
Takahiro Funami Sakie Noda Makoto Nakauma Sayaka Ishihara Rheo Takahashi Saphwan Al-Assaf Shinya Ikeda Katsuyoshi Nishinari Glyn O. Phillips 《Food Hydrocolloids》2009,23(2):548-554
Aqueous solutions of gellan gum with comparable molecular mass but with different acyl contents were investigated by atomic force microscopy and rheological measurements in the presence of sodium chloride (NaCl). Results obtained were discussed in relation to our previous report using potassium chloride (KCl) as an added salt. For a low-acyl sample, continuous fibrous network structures were identified microscopically as in the case of KCl. The network structures were more heterogeneous than those formed with KCl in terms of the height distribution of molecular assemblies. Rheological thermal hysteresis between sol–gel transitions was detected as in the case of KCl. The storage modulus (G′) of the gelled system was ca. 15% of the corresponding data with KCl at 20 °C. For a high-acyl sample, no continuous network structures were identified but branches with observable ends were identified as in the case of KCl. The hysteresis was less evident than the corresponding data with KCl and for the low-acyl sample with NaCl. Also, G′ values at 20 °C were ca. 30% and 20% of the corresponding data with KCl and for the low-acyl sample with NaCl, respectively. Continuousness and homogeneity of network structures related to the hysteresis and elasticity of the system, respectively. 相似文献
65.
66.
T. Katsumi H. Kodama T. Matsuo H. Ogawa N. Tsuboi K. Hori 《Combustion, Explosion, and Shock Waves》2009,45(4):442-453
A new composition of hydroxylammonium nitrate based solution containing ammonium nitrate, methanol, and water was developed
for monopropellant in a reaction control system (RCS) as an alternative to conventional hydrazine. In comparison with hydrazine,
this solution has a 20% higher specific impulse, 1.4 times higher density, and lower freezing point and toxicity. The linear
burning rate of the solution is moderate at the operating pressures of RCS thrusters. It was found that the linear burning
rate had some characteristics whose mechanisms had not been understood. The combustion mechanism of this solution was investigated.
The burning behavior was observed using a medium speed camera, and a temperature profile for the combustion wave was measured
with a 2.5 μm diameter thermocouple. From these results, the instability of the liquid-gas interface may trigger a sudden
increase in the burning rate, and methanol was found to be effective in reducing the bubble growth rate in the solution. The
reactivity of several catalysts was evaluated in an open-cup test, and the S405 catalyst for hydrazine showed the best performance
among them. Thruster tests were conducted using the S405 catalyst with variation in the propellant mass flow rate, catalyst
bed configuration, and length-to-diameter ratio of the combustor. As a result, parameters were determined that ensured long
operating time. The model thruster operated stably for up to 100 sec with a specific impulse I
sp = 240 sec, which corresponds to a 90% efficiency.
__________
Translated from Fizika Goreniya i Vzryva, Vol. 45, No. 4, pp. 109–120, July–August, 2009.
An erratum to this article can be found at 相似文献
67.
The In this paper, a simulator of a one‐wheel Electric Vehicle system is designed for testing an anti‐slip controller using the Motor‐Generator system. The drive motor of the M‐G system is used to simulate the drive wheel of the Electric Vehicle, and the load motor is used to simulate the load force of the chassis. In the driving process, the torque of the load motor is changed according to the drive force of the chassis that is calculated by the program. So it can simulate the dynamic process of the tire‐road system. Based on this simulator system, an anti‐slip controller based on an Adhesion Status Analyzer is proposed. Information about the wheel speed is acquired by using a Back EMF Observer. A load torque disturbance observer is designed to stabilize the acceleration of the wheels. The Adhesion Status Analyzer is used to generate safe acceleration commands for the anti‐slip controller. When a slip occurs, the anti‐slip controller will decrease the torque quickly, and at the same time, by estimating the dynamic status of adhesion, the Adhesion Status Analyzer will restrain the acceleration command within a safe area. The effectiveness of the proposed approach is verified by using the EV slip simulator. 相似文献
68.
Hiroyasu Hotokezaka Noboru Aoyagi Yasuhiro Kawahara Noriko U. Yamaguchi Shinya Nagasaki Ken Sasaki Satoru Tanaka 《Microsystem Technologies》2005,11(8-10):974-979
Laser-induced breakdown spectroscopy (LIBS) has been applied for quantitative analysis of Al2O3, CaCO3 and MgO particles suspended in water. In the single elemental system, the plasma emission intensities of Al, Ca and Mg were linearly increased with concentration of elements in the range of 1.0×10?5–1.0×10?3 M, 1.0×10?4–2.0×10?3 M and 8.0×10?5 –4.0×10?3 M, respectively. We also investigated the concentration dependence of breakdown spectra for suspended mixtures of Al2O3, CaCO3 and MgO particles. The emission lines, such as Al I, Ca I, Ca II and Mg I, were appeared in the LIBS spectrum simultaneously, and each emission peak could be deconvoluted. The plasma emission intensities of Al, Ca and Mg in the multielemental system were also linearly increased with their concentrations in the range of 1.0×10?5–1.0×10?3 M, 1.0×10?4–2.0×10?3 M and 4.0×10?4–2.0×10?3 M, respectively. LIBS was found to be available for quantitative and qualitative measurement of the concentrations of Al2O3, CaCO3 and MgO particles suspended in water. The present results suggest that LIBS is a potentially useful tool for in-situ analysis on particles composition and concentrations for environmental monitoring by the wearable information equipments. 相似文献
69.
D. Kim M. Nakagawa O. Ishikawa T. Hata T. Kodama H. Kojima 《Journal of Low Temperature Physics》1992,89(3-4):681-684
We report measurements on the effects of4He coverage and pressure on the fourth sound propagation in superfluid3He in confined geometries of four different pore sizes. 相似文献
70.
M Kodama K Akiyama H Ujike Y Shimizu Y Tanaka S Kuroda 《Canadian Metallurgical Quarterly》1998,796(1-2):273-283
The effect of acute and chronic administration of methamphetamine (METH) on the levels of activity-regulated cytoskeleton-associated protein (arc), an effector-immediate early gene, mRNA has been investigated in rat brain using in situ hybridization. Levels of arc mRNAs in the brain regions examined increased significantly from 0.5-1 h after an acute METH (4 mg/kg) administration compared with basal levels. The increase in arc mRNA continued by 3 h, and then subsided to basal levels by 6 h. The degree of increase in arc mRNA and the peak time after METH administration varied according to brain area. Arc mRNA in cerebral cortices showed robust increase 1 h after METH administration. In the striatum and hippocampus, it showed earlier and later increase, respectively, and its degree of both was less than in the cortices. Microscopic examination revealed that the METH-induced arc mRNAs in the parietal cortex were enriched in layers IV and VI, and those in the striatum existed mainly in the medium-sized neuron. Pretreatment with either 0.5 mg/kg SCH23390 or 0.25 mg/kg MK-801 almost completely blocked the enhanced striatal arc mRNA levels induced by acute METH administration, whereas such pretreatments only partially reduced the effect of METH in the cerebral cortical regions. In the chronic treatment experiment, the arc mRNA levels of the group that received chronic treatment with METH followed by a METH challenge showed an increase like seen after acute METH administration. Since previous studies proposed that arc is one of cytoskeleton-associated proteins and is selectively localized in neural dendrites, the results of the present study suggested that arc may play an important role in the synaptic plasticity underlying METH-induced adaptational changes including behavioral sensitization. 相似文献