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131.
Kumaki S. Takata H. Ajioka Y. Ooishi T. Ishihara K. Hanami A. Tsuji T. Watanabe T. Morishima C. Yoshizawa T. Sato H. Hattori S. Koshio A. Tsukamoto K. Matsumura T. 《Solid-State Circuits, IEEE Journal of》2002,37(3):450-454
A scalable single-chip 422P@ML MPEG-2 video, audio, and system encoder LSI for portable 422P@HL system is described. The encoder LSI is implemented using 0.13-μm embedded DRAM technology. It integrates 3-M logic gates and 64-Mb DRAM in an area of 99-mm2. The power consumption is suppressed to 0.7 W by adopting a low-power DRAM core. It performs real-time 422P@ML video encoding, audio encoding, and system encoding with no external DRAM. Furthermore, the encoder LSI realizes a 422P@HL video encoder with multichip configuration, due to its scalable architecture. This results in a PC-card size 422P@HL encoder for portable HDTV codec system 相似文献
132.
K Hattori S Irie Y Isobe M Wakiya T Matsumoto K Suda K Funabiki Y Tomino T Hirano K Oshimi 《Canadian Metallurgical Quarterly》1998,77(4):179-181
Researchers have recently proven the ability of computer simulation to predict the behaviour of cerebral aneurysms. Accurately simulating the flow of blood within the aneurysm helps researchers to predict the growth pattern of the aneurysm and the danger of rupturing. As this tool is further developed into a practical diagnostic tool, it is expected to dramatically improve the ability of surgeons to weigh the results of alternate treatment methods. The simulation method used, computational fluid dynamics (CFD), provides much more information than current diagnostic tools, including particularly shear stress levels at various stages of the cardiac cycle, which help to pinpoint areas of aneurysm formation and growth. 相似文献
133.
134.
Influence of Slurry Flocculation on the Character and Compaction of Spray-Dried Silicon Nitride Granules 总被引:1,自引:0,他引:1
Hideo Takahashi Nobuhiro Shinohara Masataro Okumiya Keizo Uematsu Tsubaki JunIchiro Yuji Iwamoto Hidehiro Kamiya 《Journal of the American Ceramic Society》1995,78(4):903-908
The effect of slurry flocculation on the characteristics of silicon nitride granules prepared by the spray drying process is investigated. The flocculation state of an aqueous silicon nitride slurry is controlled by adding nitric acid and evaluated as a function of pH. Dense and hard silicon nitride granules result from a well-dispersed slurry having a high pH (e.g., 10.8). These hard granules retain their shape in green compacts and form detrimental defects. Lowering the pH of the slurry to a certain value (e.g., pH 7.9) results in slurry flocculation. Granules prepared from this flocculated slurry have low density and low diametral compression strength and contribute to the elimination of large pores in green compacts. 相似文献
135.
H. Sasaki DG K. Yajima N. Yoshida T. Ishida R. Hattori T. Sonoda O. Ishihara S. Takamiya R. Konishi K. Ando 《Journal of Electronic Materials》1996,25(5):559-563
We have investigated the degradation mechanism of Al0.48In0.52As/In0.53Ga0.47As/ InP high electron mobility transistors (HEMTs) using WSi ohmic electrodes. Cross-sectional transmission electron microscopy
(TEM) observation and en-ergy dispersive x-ray (EDX) analysis reveal impurities diffusion of gate electrode (titanium: Ti)
and fluorine (F) in the AlInAs layer after a high temperature (Ta = 170°C operating life test for 500 h. The decrease of drain current (Ids) during life test shows linear dependence on square root of aging time. It suggests that the degradation is controlled by
a diffusion mechanism. Hence, the estimated degradation mechanism of this device is related with decrease of carrier concentration
in the epitaxial layer by these diffused impurities. On the other hand, TEM and EDX show no degradation of WSi/InGaAs interface
after aging. Therefore, the WSi electrode for this type of HEMT demonstrates excellent high stability under the accelerated
operating life test. 相似文献
136.
Y Nakagawa-Hattori T Hattori T Kondo Y Mizuno 《Canadian Metallurgical Quarterly》1995,45(12):2279-2281
We report thiolmethyltransferase (TMT) activity in RBC membrane preparations from patients with Parkinson's disease (PD), normal controls, and patients with symptomatic parkinsonism. Unlike previous reports, our report found no significant decrease in TMT activity in PD patients compared with normal controls. Low S-methylation capacity does not appear to be a risk factor for PD in Japanese patients. 相似文献
137.
Y Tokuhashi F Kikkawa H Ishikawa K Tamakoshi S Hattori K Matsuzawa T Inoue N Suganuma Y Tomoda 《Canadian Metallurgical Quarterly》1997,44(4):270-274
OBJECTIVE: The purpose of this study was to develop a diverting colostomy technique for use in dogs. STUDY DESIGN: Clinical case series. ANIMALS: Five client-owned dogs presented for diseases requiring diverting colostomy during treatment. METHODS: Diverting colostomy was performed in five dogs. A ventral approach was used in the first dog and the colon was exteriorized adjacent to the linea alba. The technique used in the next four dogs involved creation of a left flank rod-supported loop colostomy in which the colon was exteriorized through a muscle-separating flank approach to the abdomen. RESULTS: Peritoneal leakage of fecal material resulted in the perioperative death of the first dog. The flank colostomies were maintained for times ranging form 3.5 weeks to 7 months. No major complications were observed, but skin excoriation occurred occasionally around the stoma sites in all dogs. CONCLUSION: Diverting colostomy is a technique that is suitable for use in treatment of dogs with obstruction or leakage involving the distal colon or rectum. 相似文献
138.
Narrow and low-loss YBa2Cu3O7-δ (YBCO) coplanar lines, which can be used in multichip module technology for future high-density and high-speed digital circuits, have been developed. Etch-back planarization and a patterning process combining Ar-ion milling and wet-etching enabled us to form an 18-cm-long 5-μm-wide YBCO coplanar line without electrical shorts, even for the narrow spacing of 2.5 μm. The surface resistance of this line was kept at a level comparable to that of 10- or 25-μm-wide YBCO coplanar lines and also comparable to that of unpatterned films. This indicates successful fabrication of the 5-μm-wide YBCO coplanar line without notable loss increase resulting from process damage. The 5-μm-wide line showed a low-transmission loss of 0.49 dB at 10 GHz and 55 K. This level of loss is similar to that in Cu coaxial cables. No significant increase in transmission loss was observed up to an input power level of 16 mW at 10 GHz and 55 K. This input power is comparable to the power-handling capability required for transmitting high-speed digital signals through the lines with characteristic impedance of 50 Ω. These results show that the narrow 5-μm-wide YBCO coplanar line has great potential for high-density and high-speed digital circuits 相似文献
139.
Since the first treatment of acoustic neurinoma using the gamma-knife by Leksell, a series of cases have been reported with good control rates. However, the most frequent complication is delayed hearing loss which occurs in more than 50% of patients. The purpose of this study was to define a safe dose by analyzing the radiosurgical dose-response relationship and histological effects on the normal cochlear nerve in rabbit. The rabbits had computed tomography (CT)-guided stereotactic radiosurgery on their cochlear nerves in the internal auditory canal with a 4 mm collimator focusing of a gamma-unit. Maximum doses of 10, 20, 30, 40, 60, 80, 100, 200 and 500 Gy were administered. After the radiosurgery, auditory brain stem responses (ABR) and the behavior of the rabbits were evaluated periodically. At the conclusion, histological investigations were performed. No physiological or histological findings were observed from doses of 30 Gy or below during the 12 month period after the radiosurgery. A dose of 100 Gy caused a severe ABR threshold elevation, vestibular dysfunction and facial palsy. Necrosis and demyelination of nerves were observed pathologically. In this study, we determined that the safe dose to the normal cochlear nerve during radiosurgery was under 40 Gy in rabbits, and complications seemed to vary due to individual differences in radiation tolerance. 相似文献
140.
K. Tanabe H. Sasaki H. Hattori K. Ouchi K. Makino H. Itoh G. Takeya 《Fuel Processing Technology》1979,2(4):253-259
The activities of fourteen kinds of catalysts for the hydrocracking of Taiheiyo coal were examined by a high pressure differential thermal analytical method. Exothermic peaks appeared at low temperatures (420–430°C) when MoO3TiO2, NiY zeolite and CoY zeolite were used as catalysts, indicating that these catalysts are highly active compared with other catalysts including MoO3CoOAl2O3. The qualitative analysis of gas and liquid products revealed that MoO3TiO2 and CoY are good catalysts for the liquefaction reaction. The hydrogenation ability of the catalyst is concluded to be more important than its acidic property. 相似文献