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141.
A noise-free signal detection technique, based on the retardation method, is described. In this method, a phase-modulated light, after being transmitted through an optical transmission line, is divided into two beams in an interferometer, and temporal correlation is made on optical phase for these light beams. The original signal is regenerated by detecting light intensity variation caused by the interference phenomenon. The light detection part structure and its optimum parameters are described. The basic retardation detection system behavior was successfully confirmed experimentally. Characteristics of the retardation method are clarified, compared to those for the heterodyne detection method. 相似文献
142.
The release of 133Xe from (Th,U)O2 was studied at a low fission density by using a post-irradiation technique. The uranium concentrations of the specimens ranged from 0.15 to 20 mol% U02. Heating curves of the release gave almost the same pattern in shape, while the total release, which was the combination of an in-pile release and a post-irradiation release up to 1000°C, increased with uranium concentration except for the nominally pure ThO2. Effects of preparation conditions of specimens such as atmosphere, temperature and stoichiometry were also studied and found to be minor. Possible release mechanisms were discussed. 相似文献
143.
In situ heating and electron-beam irradiation in the transmission electron microscope were performed to study melting of Al-11.6 at.% Si alloy submicron particles supported on an amorphous-C thin film. It was found that electron irradiation could be used to melt the particles, even when the hot-stage specimen holder was kept at a much lower temperature than the bulk melting point (i.e. the eutectic temperature) of the particles. The critical current densities required to achieve partial melting increased linearly with the incident electron-beam energy for a given temperature. Comparison between this behavior and analytical calculations indicates that melting under electron-beam irradiation is caused by a temperature rise due to electron thermal spikes in the particles and poor thermal conduction away from the particles. The motion of the crystalline Al nanosphere inside the partially molten particles was also investigated, using the electron beam to both stimulate and observe the motion of the nanosphere. The irregular motion observed was quantified as antipersistent fractional Brownian motion. Analysis of possible phenomena contributing to the motion demonstrates that the incident electrons provide the fractional force that moves the Al nanosphere, and that gravity and the oxide shell on the partially molten particle cause the antipersistent behavior. Another interesting phenomenon observed in this study was that the crystalline Al nanosphere inside the partially molten Al-Si alloy particle followed a focused electron beam as it was moved about on the partially molten particle. This observation suggests that it may be possible to manipulate metallic nanospheres inside opaque liquids using an electron beam. 相似文献
144.
To better understand the crack closure effect in the fatigue process, influence of fatigue stress amplitude and R ratio on the contact features of fracture surfaces in an annealed carbon steel was studied via two special experimental approaches: (i) the collection of the fracture debris fallen from the crack surfaces, and (ii) the direct observation of the contact zones on the fracture surface through an ink dyeing method. The results of this study show that the change of fatigue CMOD value as a function of a/W ratio depends strongly on the loading condition; the fatigue stress amplitude and R ratio are the major factors that determine the contacting status between the mating fracture surfaces; the severity of the fracture surface contact can also be characterized by the dropping rate of the fracture debris particles collected during the fatigue test. 相似文献
145.
Aji Sutrisno Mitsuhiro Ueda Hiroshi Inui Takashi Kawaguchi Yoshihisa Nakano Motoo Arai Kazutaka Miyatake 《Journal of Bioscience and Bioengineering》2001,91(6):599
A gene encoding chitinase from Aeromonas sp. no. 10S-24 was expressed using pTrc99A in Escherichia coli JM 105 which yielded a 5-fold higher activity than when pUC19 was used. Three different truncated enzymes (SA-1, SA-2 and SA-3) were obtained after purification. Their isoelectric points were 7.0, 6.9, and 6.7, respectively. The enzymes showed two optimum pHs, 4.0 and 7.0, when incubated with ethylene glycol chitin as the substrate, and were stable over a wide pH range (3.0–9.0). The optimum temperature was 60°C and the enzymes were stable up to 50°C. The chitinases exhibited wide substrate specificities for chitin-related compounds. 相似文献
146.
Koji Abe Tadanobu Misawa Mitsuhiro Nendai Haiyan Tian 《IEEJ Transactions on Electrical and Electronic Engineering》2006,1(4):374-382
Most current ideas for producing highlights of broadcasted sports videos are focused on scenes of scoring and receiving loud cheers. However, depending on recent performances of Japanese baseball players in the US, Japanese TV programs often show their performances as highlights in the broadcasts without depending on the highlight. This paper presents a method for segmenting broadcasted baseball videos into every inning and every plate appearance by analyzing the change of the sports ticker by a correlation coefficient. The proposed technique could be efficiently used as a preprocessing method in extracting highlight scenes about a batter from broadcasted sports videos and making an index of the videos. The experimental results have shown that the proposed method has exactly segmented broadcasted baseball videos into each inning and each plate appearance. © 2006 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
147.
To better understand the material properties of cast aluminum alloys, the mechanical properties of microscopic structures
(the eutectic structure and the α-Al phase) have been systematically examined using a special nano-indentation hardness test
machine. In this approach, a triangular indentation is applied directly to the eutectic structure or α-Al phase, and the mechanical
properties evaluated through hardness and load-strain relationships. The hardness of the eutectic phase varied, depending
on the structural characteristics of the different intermetallic compounds. High values of hardness were obtained structures
of the DO3 type, e.g., Al5FeSi, but low hardness for CuAl2 and Mg2Si. The hardness of CuAl2 and Mg2Si had almost the same values as that of the α-Al matrix. In addition, from the nano-indentation hardness test, the effects
of α-Al grain characteristics on the mechanical properties were clarified. The hardness of the α-Al grain was linearly related
to the grain size and the distance from the grain boundary, where the higher the hardness, the smaller the grain size and
the closer to the grain boundary. The hardness level was attributed to the different severity of slip resistance of the atoms
during the indentation loading. 相似文献
148.
Mitsuhiro Kadota Hiroyuki Shoji Atsushi Hatakeyama Keiji Wada 《Electrical Engineering in Japan》2019,209(3-4):26-34
This article proposes an LED driver that consists of a ceramic‐capacitor‐input rectifier and a buck‐boost converter. The LED driver has an advantage of long life because it does not contain any electrolytic capacitors. However, the issue with electrolytic capacitor‐less LED driver is that the ripple of the smoothed voltage becomes large due to insufficient capacitance of the smoothing capacitor. The proposed method, which uses the discontinuous current mode of a buck‐boost converter, reduces the output current ripple under such conditions. Experimental results using a 5.7 W LED driver prototype demonstrate that the proposed method reduces the output current ripple and that the percent flicker becomes 4.4%, which is smaller than the recommended upper limit of 8%. 相似文献
149.
150.
Junpei Sakurai Mitsuhiro Abe Masahiro Ando Yuko Aono Seiichi Hata 《Precision Engineering》2011,35(4):537-546
This paper presents a search for Ni–Nb–Zr thin film amorphous alloys for use as optical glass device molding die materials. To efficiently search for candidate materials, we used a combinatorial method to evaluate thermal stability. First, compositionally spread Ni–Nb–Zr libraries were fabricated by combinatorial arc plasma deposition (CAPD). To evaluate thermal stability, the Ni–Nb–Zr amorphous CAPD samples in the libraries were annealed in vacuum at 723 K, representing the molding temperature for glass devices, for various time periods. The phases of the annealed CAPD samples were identified using X-ray diffractometry (XRD). From XRD identification, candidate amorphous compositions with high thermal stabilities were screened. Sputter-deposited samples with the same candidate amorphous compositions were subsequently fabricated. Other desired properties for optical glass device molding die materials, including mechanical strength, linear expansion coefficient, oxidation resistance, machinability and anti-sticking properties to molten glass, were evaluated. The investigation revealed Ni36Nb39Zr25 to be a suitable composition for a new glass lens molding die material. This material exhibited a high fracture stress, σf, of 1.3 GPa, good heat resistance, good oxidation resistance, similar linear expansion coefficient as glass, good machinability, and excellent anti-sticking properties to molten glass. 相似文献