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931.
932.
We consider on‐line detection of persistently high packet‐rate flows. We assume that flow information is collected via a time‐based sliding window scheme with random packet sampling. In this framework, we propose a method of determining the threshold of the number of sampled packets, which guarantees the false negative ratio. We also formulate and solve the design problem of our scheme, where we aim to minimize the false positive ratio. We then conduct sampling experiments with public trace data and confirm that our method works well as designed. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
933.
Hidetomo Usui Kazuhiko Kuroki Seiya Nakano Kazutaka Kudo Minoru Nohara 《Journal of Electronic Materials》2014,43(6):1656-1661
We theoretically study the thermoelectric properties of electron-doped FeAs2 and hole-doped PtSe2 from a band-structure point of view using first-principles band calculations. The band structure of both materials has a peculiar band shape with a flat portion at the top (bottom) of the band, namely the pudding-mold-type band as found in Na x CoO2. The pudding-mold-type band has a quasi-one-dimensional nature in FeAs2 and a quasi-two-dimensional nature in PtSe2. We study the origins of the pudding-mold-type band and find that the \( d_{z^2} \) orbital in FeAs2, and not only the p z but also the p x and the p y orbitals in PtSe2 play an important role in making the pudding-mold-type band. We calculate the Seebeck coefficients by the Boltzmann equation approach using a tight-binding model constructed from first-principles band calculations, finding values close to experimental observations. The present study shows the general efficiency of the pudding-mold-type band. We suggest that an efficient route towards obtaining good thermoelectric materials is to realize ideal pudding-mold-type bands by modification of lattice structures. 相似文献
934.
935.
Feature selection is used for finding a feature subset that has the most discriminative information from the original feature set. In practice, since we do not know the classifier to be used after feature selection, it is desirable to find a feature subset that is universally effective for any classifier. Such a trial is called classifier-independent feature selection. In this study, we propose a novel classifier-independent feature selection method on the basis of the estimation of Bayes discrimination boundary. The experimental results on 12 real-world datasets showed the fundamental effectiveness of the proposed method. 相似文献
936.
T Izutsu T Kudo T Sato I Nishiya K Ohyashiki K Nakagawara 《Canadian Metallurgical Quarterly》1999,93(1):124-129
-Natriuretic peptides suppress adrenergic neurotransmission by a mechanism sensitive to pertussis toxin, suggesting that GTP-binding proteins are involved in the response. The major GTP-binding proteins present in the pheochromocytoma (PC12) cells used in this report are Goalpha and Gialpha2. We tested the hypothesis that the more abundant GTP-binding protein, Goalpha, mediates natriuretic peptide effects in PC12 cells by selectively ablating Goalpha from the cells with antisense oligodeoxynucleotides. The results indicate that a selective ablation of Goalpha with this technique eliminated C-type natriuretic peptide (CNP) effects and suppressed dopamine efflux evoked by a depolarizing stimulus. However, the activation of guanylyl cyclase (GC) by CNP was sustained after the Goalpha ablation. Further, Nomega-nitro-L-arginine methyl ester suppressed evoked dopamine efflux equally in the presence and absence of Goalpha. These results suggest that CNP attenuates evoked catecholamine efflux from PC12 cells by a mechanism requiring Goalpha but independent of GC activation. 相似文献
937.
The purpose of this study is to design and develop highly efficient photocatalysts that can be anchored onto a substrate,
and to this end we have prepared a titanium oxide photocatalyst using a wet process or a dry process. The results of this
study led to the successful development of highly efficient rectangular column structured titanium oxide photocatalysts which
could be anchored onto silica sheets. 相似文献
938.
Shinya Ohtsuka Masaki Koumura Kazuhisa Eguchi Masayuki Hikita 《Electrical Engineering in Japan》2005,151(3):32-40
This paper deals with partial discharge (PD) time‐sequential properties of SF6/N2/CO2 ternary gas mixture as well as SF6 and SF6/N2 gas mixture under AC and positive DC voltage applications. The measurements were carried out by changing the gas pressure up to 0.6 MPa and applied voltage with the N‐shape characteristics of breakdown voltage versus gas pressure for each tested gas considered. We obtained experimental results of the gas pressure dependence of maximum peak value of PD current pulse as well as the relationship between the time interval of PD pulses and the peak value of PD pulse. We discuss the mechanism of increase in breakdown voltage by adding CO2 into SF6/N2 gas mixtures in terms of change of PD type from streamer to leader discharge. © 2005 Wiley Periodicals, Inc. Electr Eng Jpn, 151(3): 32–40, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20073 相似文献
939.
940.
Higashi H. Masaki S. Kibune M. Matsubara S. Chiba T. Doi Y. Yamaguchi H. Takauchi H. Ishida H. Gotoh K. Tamura H. 《Solid-State Circuits, IEEE Journal of》2005,40(4):978-985
A 5-6.4 Gb/s transceiver, consisting of a parallel 12-channel transmitter (Tx), 12-channel receiver (Rx), clock generators based on LC-VCO phase-locked loops (PLLs), and a clock recovery unit, was developed. The Tx has a five-tap pre-emphasis filter, and the Rx has an equalizer with an intersymbol interference (ISI) monitor. Monitoring the ISI enables fine adjustment of loss compensation. The pre-emphasis filter in the Tx and the equalizer in the Rx compensate for transmission losses of up to 20 dB at 6.4 Gb/s, respectively. Both the Tx and Rx channels, including the PLLs, are 3.92 mm/sup 2/ in area. The transmitter dissipates 150 mW/channel at 6.4 Gb/s when compensating for a loss of 20 dB, and the receiver 90 mW/channel when compensating for the same loss. 相似文献