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61.
Nao. Fujita Y. Zushi Y. Saito 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2009,267(6):921-924
Fe-54at.%Rh thin films were irradiated with 10 MeV iodine ions at room temperature. Before and after the irradiations, the changes in magnetic properties and the lattice structure of the samples were studied by means of a SQUID magnetometer and X-ray diffraction. For the low fluence irradiation, the SQUID measurement at 20 K shows that the anti-ferromagnetic region of the thin film is changed into ferromagnetic region by the irradiation. As the film thickness is much smaller than the ion range, we can discuss the relationship between the density of energy deposited by ions and the change in magnetization quantitatively. For the high fluence irradiation, the magnetization of the film is strongly decreased by the irradiation, which can be explained as due to the change in lattice structure from B2 into A1 structure by the irradiation. 相似文献
62.
63.
Mike Tien-Chien Lee Yu-Chin Hsu Ben Chen Masahiro Fujita 《Design Automation for Embedded Systems》1997,2(3-4):319-338
ATM switch, the core technology of an ATM networking system, is one of the major products in Fujitsu telecommunication business. However, current gate–level design methodology can no longer satisfy its stringent time–to–market requirement. It becomes necessary to exploit high–level methodology to specify and synthesize the design at an abstraction level higher than logic gates. This paper presents our prototyping experience on domain–specific high–level modeling and synthesis for Fujitsu ATM switch design. We propose a high–level design methodology using VHDL, where ATM switch architectural features are considered during behavior modeling, and a high–level synthesis compiler, MEBS, is prototyped to synthesize the behavior model down to a gate–level implementation. Since the specific ATM switch architecture is incorporated into both modeling and synthesis phases, a high–quality design is efficiently derived. The synthesis results shows that given the design constraints, the proposed high–level design methodology can produce a gate–level implementation by MEBS with about 15 percent area reduction in shorter design cycle when compared with manual design. 相似文献
64.
Measurement of the flood discharge of a small-sized river using an existing digital video recording system 总被引:1,自引:0,他引:1
In this study, a closed-circuit television (CCTV) system, installed for surveillance purposes, is utilized to measure the flow rate during a flood. The procedure to determine both the angle and scale-factor of the camera is described. Then, image analysis techniques, namely the direct visual measurement method, Large-Scale PIV (LSPIV) and Space-Time Image Velocimetry (STIV), are applied to the video images recorded by the CCTV camera. The results of these methods and the conventional float measurement are compared. In addition, the accuracy of the respective methods is discussed. A set of low-quality video images of a flood during a thunderstorm that occurred under the dark ambient conditions (midnight) is analyzed using three image-based methods. The transition of the flow rate during the event is successfully estimated. 相似文献
65.
66.
P. Calvani M. Ortolani A. Lucarelli S. Lupi A. Perla P. Maselli N. Kikugawa T. Fujita 《Journal of Superconductivity》2002,15(6):539-542
The in-plane optical conductivity of three metallic La2–x
Sr
x
CuO4 single crystals with 0.10 x 0.15 has been studied between 30 and 295 K. Strong peaks in the far-infrared are observed, which cannot be explained by Drude-like models. Their similarity with peaks reported in Cu–O ladders with one-dimensional charge-ordering, their extremely low frequency, and their behavior with temperature allows us to conclude that those anomalous features are excitations of charge stripes in the Cu–O planes. 相似文献
67.
Taniguchi Shigeji Zhu Yao-Can Fujita Kazuhisa Iwamoto Nobuya 《Oxidation of Metals》2002,58(3-4):375-390
Coupon specimens of TiAl were implanted with Nb ions at an acceleration voltage of 50 kV with a dose of 1021 ions m.–2 They were then slightly oxidized during heating to 900 or 1200 K, or at 1200 K for 3.6 ksec (1 hr) in a flow of purified oxygen under atmospheric pressure. The implanted specimens and oxidized specimens were characterized and observed by AES, X-ray diffractometry, SEM, TEM, EDS, and EPMA. Implantation improves the oxidation resistance significantly by forming virtually -Al2O3 scales. The implanted layer is about 75 nm thick; the outer part of 30-nm thickness is -Ti phase and the rest of 45-nm thickness is amorphous. Heating to 900 K in O2 results in partial crystallization of the amorphous layer to Ti5Al3O2 (Z-phase) and to 1200 K results in oxide scales of 270 to 400 nm thickness consisting mainly of Al2O3. The fraction of Al2O3 in the scale increases toward the substrate. Oxidation at 1200 K for 3.6 ksec results in Al2O3-rich scales of about 400-nm thickness. The oxide grain size is very fine, about 80 nm in size, and becomes smaller toward the outer scale surface. This implies that implantation enhanced the nucleation of Al2O3 grains relative to the growth of TiO2 grains. This finding and the formation of -Ti phase are thought to be responsible for the excellent oxidation resistance obtained. 相似文献
68.
Recent computational studies (Phys. Rev. Lett. 70 (1993) 1960; Phys. Rev. B 62 (2000) 17055) predicted that friction of ordered organic monolayer had characteristic dependence on temperature, where the maximum friction was observed around rotator transition point of the monolayer. This remained to be confirmed experimentally. Using a friction force microscope (FFM) combined with a temperature regulation module, we attempted to investigate such dependence on temperature (130 K-room temperature) on a self-assembled monolayer of dodecanethiol prepared on Au(1 1 1). The observed friction showed strong dependence on temperature and good agreement with the computational prediction. 相似文献
69.
70.
Burkhard H.D. Duhaut D. Fujita M. Lima P. Murphy R. Rojas R. 《Robotics & Automation Magazine, IEEE》2002,9(2):31-38
The ultimate goal of the RoboCup initiative is stated as follows: by mid-21st century, a team of fully autonomous humanoid robot soccer players shall win the soccer game, comply with the official rule of the FIFA, against the winner of the most recent World Cup. The authors consider this goal from the perspective of how close we are to it and what has to be done to reach it 相似文献