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921.
922.
Over the next several years, this magazine will publish a series of papers, hopefully one per issue, on the subject of capacitor technology. The intention is to cover all important areas of the technology in some detail, including film, ceramic, electrolytic, and double-layer capacitors. One of the authors (S. B.) will edit the series. 相似文献
923.
Kwang Min KimJin Ho Park Jong Hee KimKyoo Young Kim 《International Journal of Hydrogen Energy》2011,36(16):9926-9935
The bipolar plate is an important component of the polymer electrolyte membrane fuel cell (PEMFC) because it supplies the pathway of the electron flow between each unit cell. The ferritic stainless steel is considered a good candidate material for bipolar plate, but it is limited to use as a bipolar plate due to its corrosion problem and high interfacial contact resistance (ICR). To explore a cost-effective method of surface modification, various chemical and heat treatments are performed with 446M ferritic stainless steel to understand the effect of the surface modifications on the ICR and the corrosion resistance. The ICR and corrosion resistance of 446M stainless steel can be effectively controlled by a proper surface modification with combined treatment of immersion in the acidic solution, followed by heat treatment. The combined chemical and heat treatment not only improves the corrosion resistance but also reduces the ICR value. 相似文献
924.
Bong Seok Park Jin Bae Park Yoon Ho Choi 《International Journal of Control, Automation and Systems》2011,9(5):888-894
This paper proposes a sliding mode formation control method for electrically driven nonholonomic mobile robots in the presence
of model uncertainties and disturbances. We use the kinematic model based on the leader-following approach for the formation
control of multiple robots. Unlike many researches considering only the kinematic model, we also consider the dynamic model
including actuator dynamics to obtain the voltage input because it is more realistic to use the voltage as input than the
velocity. Then, the sliding mode control method is used to deal with model uncertainties and disturbances acting on the mobile
robots. The stability of the proposed control system is proven using Lyapunov stability theory. Finally, we perform computer
simulations to demonstrate the performance of the proposed control system. 相似文献
925.
Ruo‐Si Fang Ya‐Chen Dong Teng‐Yang Xu Guo‐Qing He Qi‐He Chen 《International Journal of Food Science & Technology》2013,48(12):2551-2556
Ethyl carbamate (EC) is a potential carcinogenic compound present in most of the fermented foods. In this work, EC was inhibited through different strategies during vinification of Chinese yellow rice wine. EC can be inhibited by the use of ornithine in contrast to the control at peak point. However, the utilisation of urease resulted in little inhibitive effect on EC. The comparative data of intracellular ornithine transcarbamylase (OTCase) and arginine deiminase (ADI) among four experiments showed that EC was positively regulated by intracellular OTCase, but ADI was not determined. Extracellular urea and citrulline content was significantly increased by adding ornithine (P < 0.05), whereas ethanol played a minor role in EC formation. The correlation analysis between EC and OTCase or urea revealed a linear association (correlation coefficients above 0.8). These findings suggested that OTCase may be a required factor regulating EC formation during the brewing of Chinese yellow rice wine. 相似文献
926.
927.
928.
Haksung Kim Cheol Ho Pyeon Yoshinori Sakurai Tsuyoshi Misawa 《Annals of Nuclear Energy》2011,38(11):2541-2549
Significant axial variation of radial uniformity is observed in Si-ingot neutron transmutation doping in the flux screening method, and leads to non-uniform resistivity distribution for a certain part of Si-ingot. This axial variation of radial uniformity is caused by the installation of a partial neutron screen which decreases the reaction rates differently in the center and surface at the region not surrounded by the partial neutron screen. For the improvement of the specific distribution of radial uniformity in the axial direction, a new concept of axial reflector is introduced to partly change the reaction rate at a certain region of Si-ingot, and neutron irradiation experiments are carried out at the heavy water neutron irradiation facility in the Kyoto University Research Reactor. Based on the experimental and numerical results, the new axial reflector is proved to be effective for improving the axial variation of radial uniformity. 相似文献
929.
Eun Ho Kim Kyung Hak Hyun Soo Hyun Kim Yoon Keun Kwak 《Mechatronics, IEEE/ASME Transactions on》2009,14(3):317-325
Emotion recognition is one of the latest challenges in human-robot interaction. This paper describes the realization of emotional interaction for a Thinking Robot, focusing on speech emotion recognition. In general, speaker-independent systems show a lower accuracy rate compared with speaker-dependent systems, as emotional feature values depend on the speaker and their gender. However, speaker-independent systems are required for commercial applications. In this paper, a novel speaker-independent feature, the ratio of a spectral flatness measure to a spectral center (RSS), with a small variation in speakers when constructing a speaker-independent system is proposed. Gender and emotion are hierarchically classified by using the proposed feature (RSS), pitch, energy, and the mel frequency cepstral coefficients. An average recognition rate of 57.2% (plusmn 5.7%) at a 90% confidence interval is achieved with the proposed system in the speaker-independent mode. 相似文献
930.
J. M. Zhao S. L. Ho S. N. Piramanayagam J. Z. Shi 《Quality and Reliability Engineering International》2009,25(3):345-354
For the ever‐increasing recording density in hard disk drives, ultra‐low gliding height media are required. It is an immense challenge for the tape‐burnishing/wiping process of media to reduce the asperities effectively and efficiently while no scratches occur. The purpose of this paper is to characterize and then optimize the tape‐burnishing/wiping process as so to minimize the asperities without leaving any scratches on the media surface. A Taguchi experiment design method is adopted to analyze the data and acquire an optimal level combination of process parameters. The resulting optimal combination is practically implemented in tape‐burnishing/wiping the several magnetic recording media, which reveals that the average pass ratio of 5 nm glide avalanche testing increases nearly doubly to a level of 96%. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献