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排序方式: 共有1122条查询结果,搜索用时 8 毫秒
11.
Mohd Natashah Norizan Yoshinobu Miyazaki Yuji Ohishi Hiroaki Muta Ken Kurosaki Shinsuke Yamanaka 《Journal of Electronic Materials》2018,47(4):2330-2336
Nanostructuring is known to be an effective method to improve thermoelectric performance but, generally, it requires complex procedures and much labor. In the present study, self-assembled nanometer-sized composite structures of silicon (Si) and chromium disilicide (CrSi2) were easily fabricated by the rapid solidification of a melt with a eutectic composition. Ribbon-like samples were obtained with a dominant nanostructure of fine aligned lamellae with a spacing range of 20–35 nm. The thermoelectric power factor of the ribbon was observed to be 1.2 mW/mK2 at room temperature and reached 3.0 mW/mK2 at 773 K. The thermal conductivity was 65% lower than that of a bulk eutectic sample. The results suggest that this method is promising for fabricating an effective nanostructure for thermoelectric performance. 相似文献
12.
In this letter, the application of differential phase-shift keying data format in coherent optical code-division multiple-access (DPSK-OCDMA) has been proposed and investigated theoretically and experimentally to combat noise in the OCDMA system. The DPSK-OCDMA can also ease the receiver's threshold level setting and enhance the system confidentiality. 相似文献
13.
Koh M. Mizubayashi W. Iwamoto K. Murakami H. Ono T. Tsuno M. Mihara T. Shibahara K. Miyazaki S. Hirose M. 《Electron Devices, IEEE Transactions on》2001,48(2):259-264
We report on a new roadblock which will limit the gate oxide thickness scaling of MOSFETs. It is found that statistical distribution of direct tunnel leakage current through 1.2 to 2.8 nm thick gate oxides induces significant fluctuations in the threshold voltage and transconductance when the gate oxide tunnel resistance becomes comparable to gate poly-Si resistance. By calculating the measured tunnel current based on multiple scattering theory, it is shown that the device characteristics fluctuations will be problematic when the gate oxide thickness is scaled down to less than 1 nm 相似文献
14.
Daisuke Miyazaki Shoji Kawahito 《Analog Integrated Circuits and Signal Processing》2000,25(3):235-244
This paper presents a new scheme of a low-power area-efficient pipelined A/D converter using a single-ended amplifier. The proposed multiply-by-two single-ended amplifier using switched capacitor circuits has smaller DC bias current compared to the conventional fully-differential scheme, and has a small capacitor mismatch sensitivity, allowing us to use a smaller capacitance. The simple high-gain dynamic-biased regulated cascode amplifier also has an excellent switching response. These properties lead to the low-power area-efficient design of high-speed A/D converters. The estimated power dissipation of the 10-b pipelined A/D converter is less than 12 mW at 20 MSample/s. 相似文献
15.
Shoji Asai Takayuki Yamazaki Akira Miyazaki Taikan Suehara Toshio Namba Tomio Kobayashi Haruhiko Saito Takatoshi Idehara Isamu Ogawa S. Sabchevski 《Journal of Infrared, Millimeter and Terahertz Waves》2012,33(7):766-776
Positronium is an ideal system for research on QED, especially in a bound state. A discrepancy (3.9σ) is found recently between measured HFS values and the QED prediction (including up-to O(α
3 log α
− 1), where α is the fine-structure constant.). It might be due to a contribution of unknown new physics or common systematic problems
in all the previous measurements. A new method to measure HFS directly is performed using a high power gyrotron. The transition
from ortho-positronium to para-positronium has been observed with 5 σ CL, which is the first observation of M1 transition in (sub)Terahertz region. New technologies of high power gyrotrons are
developed for precision spectroscopy. 相似文献
16.
Hiroto Kondo Hideko Yomo Susumu Furukubo Nobuyuki Fukui Kazuo Nakatani Yasutsugu Kawasaki 《Journal of the Institute of Brewing》1999,105(5):293-300
Proteinase A, excreted from yeast cells into beer during fermentation in the brewing process, has been shown to degrade foam-active proteins and to decrease foam stability. In order to improve the measurement of this enzyme in beer, a new fluorescent peptide, MOCAc-Ala-Pro-Ala-Lys-Phe-Phe-Arg-Leu-Lys (Dnp)-NH2, was synthesised and applied to the accurate and rapid estimation of proteinase A in commercial beer and fermenting wort. This novel substrate is several hundred times more sensitive to proteinase A than other previously reported synthetic substrates or native protein substrates. The concentration of proteinase A in beer is closely related to foam stability and proteinase A activity was found to increase gradually during fermentation. The concentration of proteinase A excreted from yeast cells is also closely related to the vitality of pitching yeast cells. This new method was successfully applied to the evaluation of yeast vitality and the development of optimum yeast handling procedures. 相似文献
17.
Akira Miyazaki Takayuki Yamazaki Taikan Suehara Toshio Namba Shoji Asai Tomio Kobayashi Haruo Saito Toshitaka Idehara Isamu Ogawa Yoshinori Tatematsu 《Journal of Infrared, Millimeter and Terahertz Waves》2014,35(1):91-100
Positronium is an ideal system for research on Quantum Electrodynamics (QED), especially in a bound state. A discrepancy of 3.9 standard deviations has been found between the measured hyperfine structure (Ps-HFS) and the QED predictions. This may be due to the contribution of unknown new physics or common systematic effects in previous measurements, in all of which the Zeeman effect was used. We propose a new method to directly measure the Ps-HFS using a high power gyrotron. We compare two resonators which have been developed to supply sufficient power to drive the direct transition, a Fabry-Pérot resonator and a ring resonator with a diffraction grating. We plan to perform first direct measurement of Ps-HFS within the next six months. 相似文献
18.
Kaname Kanai Takahiro Miyazaki Takanori Wakita Kouki Akaike Takayoshi Yokoya Yukio Ouchi Kazuhiko Seki 《Advanced functional materials》2010,20(13):2046-2052
How annealing influences the morphology of a highly regioregular poly(3‐hexylthiophene) (RR‐P3HT) film at the substrate interface as well as the lateral inhomogeneity in the electronic structure of the film are elucidated. Whereas previous studies have reported that high‐molecular‐weight (MW) RR‐P3HT films tend to show low crystallinity even after annealing, it is found that high‐MW RR‐P3HT does show high crystallinity after annealing at high temperature for a long time. Photoemission electron microscopy (PEEM), X‐ray photoemission spectroscopy, and ultraviolet photoemission spectroscopy results clearly resolve a considerable lateral inhomogeneity in the morphology of RR‐P3HT film, which results in a variation of the electronic structure depending on the local crystallinity. The PEEM results show how annealing facilitates crystal growth in a high‐MW RR‐P3HT film. 相似文献
19.
Akio Ohta Daisuke Kanme Hideki Murakami Seiichiro Higashi Seiichi Miyazaki 《Microelectronic Engineering》2009,86(7-9):1650-1653
A stack structure consisting of ~1.5 nm-thick LaOx and ~4.0 nm-thick HfO2 was formed on thermally grown SiO2 on Si(1 0 0) by MOCVD using dipivaloymethanato precursors, and the influence of N2 annealing on interfacial reaction for this stack structure was examined by using X-ray photoelectron spectroscopy and Fourier transform infrared attenuated total reflection. We found that compositional mixing between LaOx and HfO2 becomes significant from 600 °C upwards and that interfacial reaction between HfLayOz and SiO2 proceeds consistently at 1000 °C in N2 ambience. 相似文献
20.
Robust tracking servo system considering force disturbance for the optical disk recording system 总被引:1,自引:0,他引:1
Ohishi K. Miyazaki T. Inomata K. Yanagisawa H. Koide D. Tokumaru H. 《Industrial Electronics, IEEE Transactions on》2006,53(3):838-847
This paper proposes a new robust tracking servo system for the optical disk recording system with feedforward controller based on the prediction of the tracking error. In optical recording systems, the feedback servo system must suppress the influence of force disturbance and parameter variation. To overcome this problem, this paper designs the robust feedback control system by using coprime factorization and disturbance observer. The detecting signal of the optical disk recording system is only a tracking error. Hence, the feedforward controller of the proposed tracking control system is constructed based on both the "zero-phase-error tracking" control theory and the prediction of the tracking error. The experimental results point out that the proposed tracking servo system has a quick and precise tracking response and keeps the residual tracking error below its tolerance. 相似文献