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排序方式: 共有665条查询结果,搜索用时 343 毫秒
21.
M Okada K Oki T Shirotani M Seo N Okabe K Maeda H Nishimura K Ohkuma K Oda 《Canadian Metallurgical Quarterly》1998,33(5):640-645
The aim of the study was to assess the speech discrimination ability of postlingually deaf adults implanted with the Combi 40 cochlear implant and to compare the results with the postoperative data published for other devices. The postoperative open and closed set speech perception performance of 21 consecutive patients was tested using a standardized test battery comprising a number, monosyllable, sentence, consonant and vowel discrimination test as well as a rhyme test in the sound only condition. Mean values achieved for each test 1, 6 and 12 months after "switch on" were evaluated. The results demonstrate that all patients have a substantial benefit from their implant and show a continuous improvement in their speech perception abilities with increased device experience. The mean percentages of correct answers after 12 months were 93.4 for numbers, 44.6 for monosyllables, 78.5 for sentences, 67.6 for the rhyme test, 59.8 for vowel, and 67.3 for consonant discrimination. Preoperatively, the mean discrimination score for monosyllables was 0%. The speech discrimination scores of our patients were similar or higher than described for similar patient groups implanted with other devices. The high stimulation rate of the implant system using the continuous interleaved speech processing strategy as well as a deep atraumatic electrode insertion into the apicalmost regions of the scala tympani may be the reason for good performance. 相似文献
22.
Ara T. Yamamoto S. Oda S. Matususe K. 《Industry Applications, IEEE Transactions on》1998,34(4):752-757
This paper presents a novel method to predict the starting performance of synchronous motors. This proposed strategy is based on a simple standstill response testing method using a small-capacity DC power supply unit, tentatively named the DC decay testing method in this paper, and can be applied to standstill synchronous motors with the rotor in any arbitrary position. The proposed testing method is carried out on a 10 kW, 200 V, 31.9 A, 50 Hz four-pole laminated salient-pole synchronous motor with damper windings. The results measured by on-load test and those predicted by the proposed method on starting performance clearly show the validity of the proposed method 相似文献
23.
Oda T. Kato T. Takahashi T. Shimizu K. 《Industry Applications, IEEE Transactions on》1998,34(2):268-272
Catalyst (copper-coated zeolite catalyst, i.e., Cu-ZSM-5) was used to enhance NOx removal plasma chemical reactions. Two kinds of hydrocarbons (2-propane-1-ol, 2-propanol) were added to the synthesized flue gas before the nonthermal plasma process, and their effects on NOx removal characteristics were investigated. Enhancement effects of NOx removal by the nonthermal plasma process with hydrocarbons as the additives were confirmed. Usually, the catalyst's working temperature is much higher than the room temperature. A catalytic reactor was installed after the plasma reactor. Catalytic effects on NOx removal characteristics disappeared when the synthesized flue gas temperature was increased (~250°C). When the synthesized flue gas temperature was at room temperature, about 90% NO x removal efficiency was realized with a combination of hydrocarbons, the catalytic reactor, and the pulsed discharge plasma 相似文献
24.
25.
The goal of our study is to develop a system for walking on a step using a wearable robot. Our system consists of (1) sensing of a step from the movement of the walker, (2) detection of the foot placement state related to the step, and (3) generation of gait patterns of climbing and stepping down for the step. In the generation of gait patterns for the step, toe trajectories are generated according to the height of the step to avoid collision of the swinging leg with the step. The hip trajectory is generated by an optimization technique that minimizes the sum of the joint angular jerk of the robot subject to constraints on the hip position and the velocity at toe liftoff. Each joint angle trajectory is calculated from the generated trajectories by means of inverse kinematic equations. We investigated the feasibility of the proposed sensor and control systems for two steps with different heights. 相似文献
26.
Yunosuke Abe Toshiki Aoki Hongge Jia Shingo Hadano Takeshi Namikoshi Yuriko Kakihana Lijia Liu Yu Zang Masahiro Teraguchi Takashi Kaneko 《Polymer》2012,53(11):2129-2133
A soluble and stable one-handed helical conjugated polymer without the coexistence of any other chiral moieties was successfully synthesized by asymmetric-induced polymerization of a chiral monomer having two hydroxyl groups followed by desubstitution of the chiral groups in a solid membrane state. The reason for the success was the polymer reaction was carried out in the membrane state. This is an alternative method to obtain such a unique chiral polymer which was obtained only by the helix-sense-selective polymerization (HSSP) we reported before. In addition the efficiency of the chiral induction was higher than that of the HSSP. It is interesting that the “Membrane state” acted like as if a protecting group. 相似文献
27.
统一强度理论的发展及其在土木水利等工程中的应用和经济意义 总被引:10,自引:5,他引:10
统一强度理论是在中国本土原创产生和发展起来的关于材料强度和结构强度的系统新理论。它从连续统力学最基本的单元体力学模型开始,到数学建模方法,理论公式的表述,以及一系列新的理论公式都不同于以往的各种理论。它将以往各种适合于某一类材料的单一强度理论推进为可以适合于多种材料的统一强度理论。经过40多年的发展,它不仅自己形成了系统的理论,而且将很多著名的理论包容其中,形成了范围更宽广、功能更强大的理论体系。由于它具有一个统一的力学模型,清晰的物理意义,简单的线性数学表述式,能反映材料的基本特性,即sD效应(不同的抗拉强度和抗压强度)、静水应力效应、正应力效应、中间主应力效应和中间主剪应力效应,以及结构强度分析的破坏准则效应,并且与现有的实验数据相吻合,能容易地适合许多新情况;此外,统一强度理论既容易用来取得解析解,也容易用于计算机程序取得数值解。统一强度理论已被推广应用于很多领域。在连续介质和工程应用的框架下对统一强度理论的发展及其在土木工程中的应用和经济意义进行较为系统的小结。 相似文献
28.
R.W. Callis J.L. Doane H.J. Grunloh K. Kajiwara A. Kasugai C.P. Moeller Y. Oda R.A. Olstad K. Sakamoto K. Takahashi 《Fusion Engineering and Design》2009,84(2-6):526-529
Initial testing on the Japan Atomic Energy Agency Gyrotron Test Stand of ITER-relevant TL components, has shown reasonable efficiencies, but identified that trapped modes between closely located miter bends, as well as mode conversion at miter bends can lead to excessive heating of the connecting waveguides. General Atomics has designed, built, and will test components to address this issue as well as ITER relevant components that have not been tested at the levels of 1 MW, 170 GHz, for extended pulse lengths. Some of the components that will be tested are ultra low loss miter bends, dc breaks, polarizers, power monitors, bellows, waveguide switches, waveguide cooling clamps, etc. Details of the components and test results will be presented. 相似文献
29.
The n-6/n-3 fatty acid (FA) ratio has increased in the Western-style diet to ~10–15:1 during the last century, which may have
contributed to the rise in cardiovascular disease (CVD). Prior studies have evaluated the effects on CVD risk factors of manipulating
the levels of n-6 and n-3 FA using food and supplements or investigated the metabolic fate of linoleic acid (LNA) and α-linolenic
acid (ALA) by varying the n-6/n-3 ratios. However, no previous studies have investigated the potential interaction between
diet ratios and supplementation with eicosapentaenoic acid (EPA, 20:5n-3) and docosahexaenoic acid (DHA, 22:6n-3). We used
a factorial design approach with adults (n = 24) in a controlled feeding trial to compare the accretion of EPA and DHA into red blood cell membranes (RBC) by adding
a direct source (algal oil supplement) of EPA and DHA in a diet with a 10:1 versus 2:1 ratio of n-6/n-3 FA. Subjects were
randomized into 8-week crossover diet sequences and each subject consumed three of four diets [10:1, 10:1 plus supplement
(10:1 + S), 2:1 and 2:1 + S]. LNA and ALA intakes were 9.4 and 7.7%, and 1.0 and 3.0% during the low and high ALA diets, respectively.
Compared to the Western-style 10:1 diet, the 2:1 diet increased EPA by 60% (P < 0.0001) in RBC membranes without the direct EPA source and a 34% increase (P = 0.027) was observed with the 10:1 + S diet; however, DHA levels increased in both diet ratios only with a direct DHA source.
Shifting towards a 2:1 diet is a valid alternative to taking EPA-containing supplements. 相似文献
30.
K. Kainosho M. Ohta M. Uchida M. Nakamura O. Oda 《Journal of Electronic Materials》1996,25(3):353-356
Recently, it was found that undoped semi-insulating InP can be obtained by highpressure annealing of high purity materials.
The reproducibility and the uniformity was, however, not satisfactory. In the present work, we found that not only Fe concentrations
but also Cr and Ni concentrations in annealed wafers were slightly increased during annealing. Since it seems that the origin
of the contamination was due to the vapor source of red phosphorus, conductive InP with a trace amount of Fe was annealed
under low phosphorus vapor pressure in order to reduce the contamination. By preventing the contamination of Cr and Ni, preparation
of semi-insulating InP became highly reproducible. The minimum Fe concentration for realizing semi-insulating InP was found
to be 1 x 1015cm−3. It was also found that the better resistivity uniformity can be obtained at higher annealing temperatures. 相似文献