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排序方式: 共有742条查询结果,搜索用时 15 毫秒
91.
Kazuhiko Kakuda Nobuyoshi Tosaka 《International journal for numerical methods in engineering》1990,29(2):245-261
The generalized boundary element method is presented for the numerical solution of Burgers' equation. The new method is based on the set of boundary integral equations derived for each subdomain by using the fundamental solution for the linearized differential operator of the equation. The resulting system of quasi-non-linear equations is solved implicitly with use of a simple iterative procedure. The adaptability and the accuracy of the proposed method are demonstrated by three examples and a comparison of the numerical results with the exact solution or other existing solutions is shown for the first example. 相似文献
92.
Monolithic wide-band amplifiers have been demonstrated using AlGaAs/InxGa1-xAs/GaAs pseudomorphic two-dimensional electron-gas field-effect transistors. The amplifiers have yielded an 18.0 GHz bandwidth and a 41.8 dBΩ transimpedance gain with a feedback resistance of 100 Ω. In addition, the dependence of In mole fraction for an InxGa1-xAs channel layer on device and amplifier performance has been also investigated. The gm and the fT in a device, along with the bandwidth, the gain, and the noise performance in an amplifier, have improved as the In mole fraction is varied from 0 to 0.25 相似文献
93.
94.
H Honjo H Kitakoji K Kawakita M Saitoh O Ukimuta M Kojima H Watanabe S Aramaki 《Canadian Metallurgical Quarterly》1998,89(7):665-669
PURPOSE: We investigated the possible use of acupuncture for the treatment of urinary incontinence caused by detrusor hyperflexia in patients with chronic spinal cord injury. METHOD: A total of 8 male chronic spinal cord injured patients with urinary incontinence were treated by acupuncture. Their ages ranged from 20 to 33 years (mean 27). The level of lesion was cervical in 4 and thoracic in 4. Detrusor hyperreflexia with uninhibited bladder contraction was confirmed by urodynamic studies in all of them. Acupuncture was performed using a disposable stainless needle (0.3 mm in diameter, 60 mm in length), which was inserted into bilateral BL-33 (Zhongliao) points and was rotated manually for 10 minutes. The treatment was conducted every week for 4 weeks. Urodynamic studies were repeated, immediately after the beginning of and a week after the completion of the treatment. Urinary symptoms were also checked before and after the treatment. RESULTS: No side effects were recognized throughout the treatment period. Among 8 patients, incontinence was controlled completely in 3 (38%) and partially in 3 (38%). The average maximum cystometric bladder capacity increased significantly, from 42.3 +/- 37.9 ml to 148.1 +/- 101.2 ml by the treatment (p < 0.05), while the average maximum bladder pressure was not changed. CONCLUSIONS: These data suggest that acupuncture could be a promising alternative for conventional therapies for urinary incontinence caused by detrusor hyperreflexia in patients with chronic spinal cord injuries. 相似文献
95.
Takayuki Tomaru Shinji Miyoki Masatake Ohashi Kazuaki Kuroda Takashi Uchiyama Toshikazu Suzuki Akira Yamamoto Takakazu Shintomi Akitoshi Ueda Daisuke Tatsumi Shuichi Sato Koji Arai Masaki Ando Koji Watanabe Kenji Nakamura Masahiko Watanabe Kazuhiko Ito Izumi Kataoka Hiroaki Yamamoto Brett Bochner Yaron Hefetz 《Applied optics》2003,42(7):1306-1307
96.
Kenji Wada Kazuhiko Hirabayashi Naoki Watanabe Shingo Yamamoto Teruyuki Kondo Take-aki Mitsudo Masashi Inoue 《Topics in Catalysis》2009,52(6-7):693-698
Novel Ti-containing silsesquioxane gel catalysts were prepared by the hydrosilylative condensation of Ti-containing silsesquioxanes together with cubic silsesquioxanes and spherosilicates. The porosity of gels was controlled by changing the composition and the mixing order of the starting materials. Both porous and nonporous gels were found to act as excellent heterogeneous catalysts towards the selective epoxidation of cyclooctene by the use of aqueous hydrogen peroxide as an oxidant. 相似文献
97.
T Hirota T Honjo R Kuroda K Saeki N Katano Y Sakakibara H Shimizu T Fujimoto 《Canadian Metallurgical Quarterly》1993,20(15):2369-2373
A crossover clinical trial was carried out to compare the effectiveness and safety of granisetron alone (40 micrograms/kg) with that from a combination of granisetron plus methylprednisolone (MPL, 10 mg/kg) for control of emesis and vomiting induced by anticancer drugs in children with cancer. Complete control of emesis and vomiting were achieved in 95% (19/20 cases) of patients receiving the combination compared to 85% (17/20 cases) of patients receiving granisetron alone. There were no clinical toxicities or side effects in either treatment group. These data indicated that the combination of granisetron plus MPL was superior for control of emesis and vomiting in children receiving cytostatic anticancer drugs. 相似文献
98.
Estimates of behavioral thresholds of infants are elevated relative to those of adults. Explanations for the differences include auditory sensory factors and non-sensory factors, but no direct estimates of the relative contributions of these two factors have been made. In this investigation, thresholds in quiet and in increasing levels of a masking noise for a 1 kHz tone, in infants 8 to 11 months old and in adults, were determined. The infant-adult differences in unmasked threshold was compared to the infant-adult difference in an estimate of the minimum masking level (MML) that was derived from the masking data. The intensity level of a masking noise at which masking begins is assumed to be independent of the non-sensory factors that impact on the threshold value itself. Therefore, it is reasoned that the infant-adult difference in MML reflects more closely differences in auditory sensory factors than does the infant-adult difference in unmasked threshold. In the region of 1 kHz, the infant-adult difference in behavioral threshold was 12 dB and the infant-adult difference in MML was 8 dB. Therefore, according to our assumptions, 8 dB of the infant-adult difference in unmasked threshold is accounted for by sensory factors and the remaining 4 dB must be attributable to non-sensory factors. 相似文献
99.
Shuzo Morita Tsuneo Katsuyama Kazuhiko Ito Hichiro Hayami 《International Journal of Communication Systems》1989,2(1):3-11
This paper proposes a new integrated switching system, ‘elastic basket switching’, for broadband and multimedia communications, including voice and high-speed data. In elastic basket switching (EBS), it is possible flexibly and efficiently to handle multimedia information by adaptively assigning communication resources according to communication requests and bandwidth of switched information. For continuous information, such as voice, EBS functions just as a circuit switching system, and for burst data it achieves high-efficiency bandwidth usage equivalent to a packet switching system by demand-assign type time-slot assignment. The detail of EBS and its application to a departmental system-orientated PBX are described. The traffic handling capability and details of the hardware structure are presented. The experimental system, including use of LSIs in the main parts of EBS is also described. 相似文献
100.
We developed a micro total analysis system (mu-TAS) incorporating chemiluminescence detection, in which the chemiluminescence reaction of isoluminol isothiocyanato (ILITC) (as a chemiluminescence reagent for labeling)-microperoxidase (as a catalyst)-hydrogen peroxide (as an oxidant) was adopted. The analysis system performed the following three processes on a microchip: immune reaction for high selectivity, electrophoresis for formation and transportation of the sample plug, and chemiluminescence detection for high sensitivity. The three processes were compactly integrated onto the microchip to give the mu-TAS. The microchip contained two microchannels that crossed at an intersection, while the ends of the microchannels accessed four reservoirs. As the first process, the immune reaction was performed using an antibody-immobilized glass bead. The glass bead was placed in one of the reservoirs along with antigen (analyte) and a known amount of ILITC-labeled antigen to set up a competitive immune reaction. For electrophoresis, as the second process, the reactant after the immune reaction was fed electrophoretically into the intersection resulting in a sample plug. The sample plug was then moved into another reservoir containing hydrogen peroxide solution. At this point, chemiluminescence detection was performed as the third process: the labeled antigen mixed with the hydrogen peroxide and the catalyst included in the migration buffer to produce chemiluminescence. Chemiluminescence was detected by a photomultiplier tube located under the reservoir. The mu-TAS described here was capable of determining, with high selectivity and sensitivity, human serum albumin or immunosuppressive acidic protein as a cancer marker in human serum. 相似文献