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91.
Telecommunication Systems - 相似文献
92.
M Izumi S Ohwada S Kawate N Tokizawa T Anzai A Sasaki Y Morishita 《Canadian Metallurgical Quarterly》1997,24(10):1321-1325
A 50-year-old man with moderately differentiated adenocarcinoma of the rectum was operated upon following preoperative administration of FT suppository. Digital examination, colonoscopy, and barium enema showed an elevated lesion with central ulcer of the rectum. Microscopically, the biopsy specimen demonstrated moderately differentiated adenocarcinoma. FT suppository (1,500 mg/day for 52 days, total 78 g) was administered on an outpatient basis. Rectal amputation including lymph node dissection was performed. The tumor markedly reduced in size and changed into a small ulcer in the resected specimen. Microscopically, the tumor degenerated and changed into xanthogranulomatous tissue with foamy histiocytes. Only two tubules of degenerated adenocarcinoma remained. FT suppository for rectal cancer is considered to be safe and effective. 相似文献
93.
We report a rare case with rupture of thymic cyst including mediastinal hemorrhage and hemothorax. A 68-year-old man was referred to our hospital for the treatment of right hemothorax. A chest roentgenogram following thoracentesis demonstrated a widened mediastinum. Chest computed tomograms revealed a large anterior mediastinal mass extending to the right pleural cavity and bilateral pleural effusion. Digital subtraction angiography showed a normal aorta and great vessels. A median stenotomy revealed a large encysted hematoma along the thymic cyst extending from the right anterior mediastinum into the right pleural cavity and ending with rupture. Pathological examination demonstrated that the largest thymic cyst was continued to the hematoma resulting from partial destruction of its epithelial lining. To our knowledge, only five cases including our's with ruptured thymic tumors were reported, and this is the first report of ruptured thymic cyst resulting in mediastinal hemorrhage and hemothorax. 相似文献
94.
Norio Tokuda Hitoshi Umezawa Sung-Gi Ri Masahiko Ogura Kikuo Yamabe Hideyo Okushi Satoshi Yamasaki 《Diamond and Related Materials》2008,17(7-10):1051-1054
A process of homoepitaxial growth of diamond (111) films by microwave plasma-enhanced chemical vapor deposition has been investigated characterizing areas by ex-situ atomic force microscopy. The evolution of surface morphology during a lateral growth of (111) diamond was visualized utilizing a mesa structure as a marker. Lateral growth forms atomically flat surfaces, which show atomically flat terraces over several hundred nm widths and single bilayer steps of (111) diamond. 相似文献
95.
Debasish Chakraborty Goutam Chakraborty Norio Shiratori 《International Journal of Network Management》2003,13(5):321-335
In this paper we propose a QoS‐based routing algorithm for dynamic multicasting. The complexity of the problem can be reduced to a simple shortest path problem by applying a Weighted Fair Queuing (WFQ) service discipline. Using a modified Bellman–Ford algorithm, the proposed routing builds a multicast tree, where a node is added to the existing multicast tree without re‐routing and satisfying QoS constraints. With user defined life‐time of connection this heuristic algorthm builds multicast tree which is near optimum over the whole duration of session. Simulation results show that tree costs are nearly as good as other dynamic multicast routings that does not consider QoS. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
96.
Young-Kong Ahn Shin Morishita Bo-Suk Yang 《Journal of Mechanical Science and Technology》1998,12(6):1097-1103
Liquid crystals (LC) are characterized by its phase, which appears as an intermediate state between crystalline solid and
isotropic liquid. This intermediate, phase is caused by orientation of molecules, and it can be controlled by an externally
applied electric or magnetic field. Subjected to an electric field, the viscosity of the LC varies according to the applied
electric field strength, which is called the electroviscous effect. This paper describes an application study of the electroviscous
effect of a LC to a controllable squeeze film damper (SFD) for a rotating machine. A prototype controllable SFD using a LC
was constructed and its performance was studied. It should be noted that the present SFD can produce anisotropic damping force
for a flexible rotor at the supporting position, which enables us to stabilize a flexible rotor in a wide range of its rotating
speed. 相似文献
97.
Jun-Ichiro Hayashi Masahiro IwatsukiKayoko Morishita Atsushi TsutsumiChun-Zhu Li Tadatoshi Chiba 《Fuel》2002,81(15):1977-1987
Two pairs of raw and acid-washed coal samples were prepared from Yallourn and Loy Yang brown coals, and subjected to rapid pyrolysis in a drop-tube reactor at 1073-1173 K in a stream of N2 or H2O/N2 mixture. Examinations were made on the roles of the inherent metallic species in the secondary reactions of nascent tar and char that were formed by the intraparticle primary reactions. The experimental results revealed that the inherent metallic species were essential for vary rapid steam reforming/gasification of the nascent tar/char and simultaneous suppression of soot formation. In the absence of the metallic species, the soot formation from the tar accounted as much as 15-19 and 6-13% of the carbon in coal in N2 and H2O/N2, respectively. The metallic species reduced the yield of soot to 6-8% in N2 by enhancing the reforming of tar by H2O generated from the pyrolysis of coal. In the H2O/N2 stream, instead of soot formation, a net gasification conversion up to 17% within 4.3 s was observed in the presence of the metallic species as a result of catalytic gasification of the nascent char. Moreover, the metallic species catalyzed the steam reforming of the nascent tar, giving its conversion up to 99%. Over the range of the conditions employed, a one-to-one stoichiometry was established between the steam consumption and the yield of carbon oxides formed by the steam reforming/gasification and water-gas-shift reaction. 相似文献
98.
The so-called pseudo-orthogonal property of the eigenfunction expansion form is proved to be valid for the case of an antiplane interface V-notch and the corresponding path-independent integral is derived. The relation between the path-independent integral and the stress intensity factor of the notch is found. The influence of loads on the related integral is also presented. 相似文献
99.
Summary Introduction of isocyanate (NCO) group onto carbon black surface was achieved by the treatment of carbon black with toluene-2,4-diisocyanate. In addition, carbon black having acyl azide (CON3) group, a precursor of NCO group, was prepared by the reaction of COCl or COOCOOC2H5 group on carbon black with NaN3. The CON3 group on carbon black was relatively stable at below 20°C but readily decomposed to NCO group by heating (Curtius rearrangement). By the reation of NCO group on carbon black with hydroxyl group of polymers, such as polypropylene glycol, polyethylene glycol, and polyvinyl alcohol, these polymers were found to be grafted onto carbon black. 相似文献
100.
Hiroshi Taniguchi Toshiaki Ohmori Misao Iwata Norio Arai Kenji Hiraga Shun‐ichi Yamaguchi 《亚洲传热研究》2002,31(5):391-407
In this study, the authors attempted to introduce a simulation technique for radiation‐convection heat transfer in the high‐temperature fields of industrial furnaces, boilers, and gas turbine combustors. The convection effect was analyzed by a differential equation, but the radiation effect was analyzed by an integral equation. Thus, it was not easy to arrange both effects using the same type of equations. Then, the authors introduced the zone method and Monte Carlo method for the integral equation of the radiation effect and the finite difference method for the differential equation of the convection effect. A three‐dimensional analysis of the high‐temperature furnace was performed by this simulation technique to obtain its temperature distribution. Furthermore, another radiation‐convection heat transfer analysis in the low‐temperature living room was performed by the same technique. Finally, the authors tried to develop a computer software for radiation‐convection heat transfer and described their idea of software construction for the above. © 2002 Wiley Periodicals, Inc. Heat Trans Asian Res, 31(5): 391–407, 2002; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/htj.10042 相似文献