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941.
Soon Ki Kim Sung Hyun Hwang Jun-Tae Nam Jong-Sung Park 《Ceramics International》2021,47(15):21083-21089
Generally, the NiO composite anode becomes porous after reduction. To infiltrate additional catalysts such as Pd into the NiO-composite anode before reducing NiO to Ni, a porous NiO composite anode for protonic ceramic fuel cells (PCFCs) was fabricated in this study. The porous NiO composite was fabricated by adding graphite as a pore former along with CuO as a sintering agent. The addition of graphite increased the porosity of the NiO composite anode but resulted in poor sinterability, which was addressed by adding CuO as a sintering agent to the NiO composite anode. The Pd catalyst was added to the NiO-composite anode before reducing NiO to Ni. The composite anode for PCFC with three components, namely Ni, protonic ceramics, and a Pd catalyst, was obtained by reducing NiO to Ni during the measurement. The addition of the Pd catalyst improved the anode performance in methane fuel and hydrogen fuel by enhancing the catalytic activity for the electrochemical reaction on the surface. 相似文献
942.
Objective and quantitative assessment of skin conditions is essential for cosmeceutical studies and research on skin aging and skin regeneration. Various handcraft-based image processing methods have been proposed to evaluate skin conditions objectively, but they have unavoidable disadvantages when used to analyze skin features accurately. This study proposes a hybrid segmentation scheme consisting of Deeplab v3+ with an Inception-ResNet-v2 backbone, LightGBM, and morphological processing (MP) to overcome the shortcomings of handcraft-based approaches. First, we apply Deeplab v3+ with an Inception-ResNet-v2 backbone for pixel segmentation of skin wrinkles and cells. Then, LightGBM and MP are used to enhance the pixel segmentation quality. Finally, we determine several skin features based on the results of wrinkle and cell segmentation. Our proposed segmentation scheme achieved a mean accuracy of 0.854, mean of intersection over union of 0.749, and mean boundary F1 score of 0.852, which achieved 1.1%, 6.7%, and 14.8% improvement over the panoptic-based semantic segmentation method, respectively. 相似文献
943.
A resilient buffer allocation scheme in active queue management: a stochastic cooperative game theoretic approach
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During the last decade, a plentiful number of active queue management schemes have been proposed, but their main objectives are simply allocating the buffer resource to all flows evenly, or protecting responsive flows from being degraded by unresponsive flows. However, the sending rates of the responsive flows can be determined diversely, and not all unresponsive flows have aggressively high sending rates. Furthermore, it is rational to reserve a portion of the buffer resource for certain privileged traffic. Grounded by these evidences, in this paper, we present a resilient active queue management algorithm, named Prior‐Core‐based Buffer Allocation considering diverse congestion control algorithms, fair‐unresponsive flows, and some privileged traffic. Our approach is based on stochastic cooperative game theory, where the payoffs yielded by cooperation are described by random variables, and the core is defined only over the distribution of these random payoffs; the core in this situation is called the prior‐core. As a result, it is shown that our buffer allocation, yielded by the prior‐core, achieves completely fair allocation for those flows whose requirement does not exceed the fair‐share regardless of the responsiveness, whereas aggressive flows are restricted according to availability of the buffer; all these are verified through ns‐2 simulation experiments. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
944.
Han Seong-Soo Kim Yoon-Ki Jeon You-Boo Park JinSoo Park Doo-Soon Hwang DuHyun Jeong Chang-Sung 《The Journal of supercomputing》2020,76(7):5460-5485
The Journal of Supercomputing - IT technology and traditional industries have been combined recently, resulting in IT convergence technology in various fields. Through convergence with the... 相似文献
945.
Ho-Sun?Hwang Uoo-Chang?ChungEmail author Won-Sub?Chung Young-Rae?Cho Byong-Ho?Jung G.?P.?Martin 《Metals and Materials International》2004,10(1):77-82
Iron carbides formed on the surface of iron and iron oxide samples at 640 °C in a gas mixture of CO?H2 were characterized by scanning electron microscopy (SEM), Mössbauer spectroscopy, X-ray diffraction patterns (XRD), and by measuring mass change. The Fe3C amount of the samples has been quantitatively evaluated by the weight change during carburization. While Fe2O3 powder was mostly completed to Fe3C in the early stage, within 5 min after reduction reactions, the conversion of Fe powder sample to Fe3C (iron carbide) was almost finished after 10 min. The carburization rate of a Fe sheet was very slow and intermediate products (Fe2C, Fe5C2) were observed. This phenomenon is largely due to the difficulty of carbon diffusion into its dense surface. It was found that the carburization rate was affected by change of surface conditions and surface area by reduction, degradation, and cracks at high temperature. This study should help provide a fundamental understanding of carburization in the field of iron-making and suggest a direction for its further development. 相似文献
946.
WT Chang IS Hwang MT Chang CY Lin WH Hsu JL Hou 《The Review of scientific instruments》2012,83(8):083704
We demonstrate a new and simple process to fabricate tungsten tips with good control of the tip profile. In this process, we use a commercial function generator without any electronic cutoff circuit or complex mechanical setup. The tip length can be varied from 160 μm to 10 mm, corresponding to an aspect ratio of 1.6-100. The radius of curvature of the tip apex can be controlled to a size <10 nm. Surface roughness and the taper angle can be controlled independently. Through control of the etching parameters, the tip length, the radius of curvature, surface roughness, and the taper angle can be controlled to suit different requirements of various applications. The possible etching mechanisms are also discussed. 相似文献
947.
Lundbom Jesper Bierwagen Alessandra Bodis Kalman Apostolopoulou Maria Szendroedi Julia Müssig Karsten Hwang Jong-Hee Roden Michael 《Magma (New York, N.Y.)》2019,32(5):591-597
Magnetic Resonance Materials in Physics, Biology and Medicine - There is a discrepancy between studies suggesting that higher bone marrow fat saturation is associated with impaired health, and... 相似文献
948.
949.
End-face scattering loss in integrated-optical waveguides 总被引:3,自引:0,他引:3
An experimental technique to determine the end-face scattering loss in electro-optic polymer channel waveguides is presented. The technique combines the cut-back and the optimum end-fire coupling methods. A loss resulting from the scattering was a prominent source of waveguide coupling loss and was strongly dependent on the end-face roughness of the guiding and cladding layers induced by cleaving. With the use of our investigation methods, other losses could also be examined with ease and high reliability. 相似文献
950.
Based on the combinatorial Routh- and- expansions of a stable transfer function, a new energy decomposition tree for linear systems is developed. The pertinent properties to the energy decomposition tree are investigated, and an algorithm is derived for synthesizing transfer functions from the tree. The synthesis process naturally leads to a new family of Routh approximants to the system. It is indicated that the selection of Routh approximants based on the values of impulse-response energy is often inadequate because there may be a number of different Routh approximants with the same order and the same impulse-response energy. In such cases, an additional performance criterion, such as the integral of squared error of impulse response or unit-step response, has to be used to select a suitable Routh approximant.This work was supported by the National Science Council of the Republic of China under Grant NSC80-0402-E006-12. 相似文献