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41.
Chang-Wan Kim Joo-Hyun Choi Hyung-Jun Kim Dong-Won Lee Chang-Yong Hyun Song-Min Nam 《Ceramics International》2012,38(7):5621-5627
The influence of the surface roughness of Al2O3 interlayers on the growth of Al2O3 thick films fabricated by an aerosol deposition (AD) process was investigated as an approach to improving the plasma resistance of the films. The Al2O3 interlayer was fabricated by a plasma electrolytic oxide (PEO) method. This method is capable of fabricating films on the entire surface area of 3-dimensional substrates, whereas the AD process has difficulties with depositing films on complex shapes, such as on edges and corners, and inside holes. To prevent degradation of the plasma resistance with increasing working time, the thickness of the Al2O3 interlayer was increased by the PEO method. The surface roughness of the Al2O3 interlayer was increased linearly by increasing the thickness of the Al2O3 interlayer. On Al2O3 interlayers with surface roughness values of more than 1.5 μm (Ra), Al2O3 films were not grown by the AD process. To investigate the effect of the surface roughness of the Al2O3 interlayer on the growth of Al2O3 films on the Al2O3 interlayer, we attempted to deposit Al2O3 films on an Al2O3 interlayer whose surface roughness was decreased from 1.5 μm to 0.8 μm by polishing. As a result, an Al2O3 film of 2.0 μm in thickness was grown by the AD process. These study results support the conclusion that controlling of the surface roughness is the most important factor in aerosol-deposited film growth. 相似文献
42.
We report a top-down approach based on atomic force microscope (AFM) local anodic oxidation (LAO) for the fabrications of the nanowire and nano-ribbon field effect transistors (FETs). In order to investigate the transport characteristics of nano-channel, we fabricated simple FET structures with channel width W approximately 300 nm (nanowire) and 10 microm (nano-ribbon) on 20 nm-thick silicon-on-insulator (SOL) wafers. In order to investigate the transport behavior in the device with different channel geometries, we have performed detailed two-dimensional simulations of nanowire and reference nano-ribbon FETs with a fixed channel length L and thickness t but varying channel width W from 300 nm to 10 microm. By evaluating the charge distributions, we have shown that the increase of 'on state' conduction current in SiNW channel is a dominant factor, which consequently result in the improved on/off current ratio of the nanowire FET. 相似文献
43.
Zhao-Pin Su Jian-Guo Jiang Chang-Yong Liang Guo-Fu Zhang 《Canadian Metallurgical Quarterly》2011,8(1)
Suitable rescue path selection is very important to rescue lives and reduce the loss of disasters,and has been a key issue in the field of disaster response management.In this paper,we present a path selection algorithm based on Q-learning for disaster response applications.We assume that a rescue team is an agent,which is operating in a dynamic and dangerous environment and needs to find a safe and short path in the least time.We first propose a path selection model for disaster response management,and deduce that path selection based on our model is a Markov decision process.Then,we introduce Q-learning and design strategies for action selection and to avoid cyclic path.Finally,experimental results show that our algorithm can find a safe and short path in the dynamic and dangerous environment,which can provide a specific and significant reference for practical management in disaster response applications. 相似文献
44.
Moisture Sorption Characteristics of Freeze Dried Blueberries 总被引:2,自引:0,他引:2
Moisture sorption isotherms of freeze dried lowbush blueberries at 4, 16, 25, 35, and 45°C were determined using indirect gravimetric method. Moisture sorption kinetics at these temperatures and 75% RH were also investigated. The isotherms followed a type III shape with a temperature inversion effect at 0.9 water activity. They were best described by the GAB equation. Net isosteric heat of moisture sorption in freeze dried blueberries, determined using the Clausius Clapeyron equation, varied from 5.5 to 0.25 kJ/mol as moisture content changed from 8 to 36% (dry basis). Moisture adsorption kinetics in freeze dried blueberries were well described by the first order kinetics equation. The rate constant followed the Arrhenius relationship with an activation energy of 38.6 kJ/mol. 相似文献
45.
评估内燃机隔振系统功率流传递的一种新模型(英文) 总被引:1,自引:0,他引:1
为准确评估弹性复杂隔振基础条件下振动内燃机的功率流传递水平,采用 Mindlin 板替代传统的Kirchihoff 薄板,建立了一种涵盖多种隔振基础形式的普适模型.运用子结构技术和变分理论,推导了隔振系统的控制方程以及传递到较厚甚至不同配置方式的各向异性复杂梁式基础的功率流.与基于各向同性薄板基础的传统模型相比较,研究了普适隔振系统功率流的传递特性.仿真研究表明,所提模型是有效的,可得到比传统模型更加准确的结果. 相似文献
46.
47.
The consideration of orbital angular momentum of an electric field(twisted mode) is applied to the kinetic theory of plasma. The linearized Vlasov–Poisson equation is solved for the anisotropic thermal distributed bi-Maxwellian and Cairns distributions of electrons to obtain the damping rates of twisted waves. The dispersion relation and Landau damping of Langmuir twisted modes are obtained. The presence of twisted modes opens up two more possibilities in Landau damping and dispersion relations. This may generate a mixture with ion sound waves. It seems to play the role of a control parameter of Landau damping. 相似文献
48.
ZHU Jing LIM Xi Wei XU Hai Gang HU Jin Sheng LU Hong Xiu Guo Wei ZHAO Xiang Rong JIA Li Ping YE Heng Qiang andNIHG Xiao Guang 《钢铁研究学报(英文版)》1994,(1)
StudiesofCharacterizationofMicrostructuresforLowDimensionalMaterialsZHUJing;LIMXiWei;XUHaiGang;HUJinSheng;LUHongXiu;GuoWei;ZH... 相似文献
49.
Zhi-Xing Yang Meng Han Chang-Yong Pan Jun Wang Lin Yang Ai-Dong Men 《Broadcasting, IEEE Transactions on》2004,50(1):26-31
In this paper a channel coding and modulation scheme for providing HDTV broadcasting services is presented, which adopts BICM structure as inner code in connection with 64QAM constellation and OFDM transmission. A new mapping method is designed to maximize the minimum Euclidean distance between signal points divided by feedback bits, thus an iterative algorithm between demodulator and decoder can be performed to acquire performance improvement. Analysis, simulation and laboratory test results have proved that the proposed system has good SNR performance in both AWGN and multipath channels. 相似文献
50.