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31.
General Model to Predict Power Flow Transmitted into Laminated Beam Bases in Flexible Isolation Systems 总被引:1,自引:0,他引:1
For estimating the vibration transmission accurately and performing vibration control efficiently in isolation systems, a novel general model is presented to predict the power flow transmitted into the complicate flexible bases of laminated beams. In the model, the laminated beam bases are simulated by the first-order shear deformation laminated plate theory, which is relatively simple and economic but accurate in predicting the vibration solutions of flexible isolation systems with laminated beam bases in comparison with classical laminated beam theories and higher order theories. On the basis of the presented model, substructure technique and variational principle are employed to obtain the governing equation of the isolation system and the power flow solution. Then, the vibration characteristics of the flexible isolation systems with laminated bases are investigated. Several numerical examples are given to show the validity and efficiency of the presented model. It is concluded that the presented model is the extension of the classical one and it can obtain more accurate power flow solutions. 相似文献
32.
The paper proposes a colorfulness enhancement of pictorial images using image classifier based on chroma histogram.This ap-poach firstly estimates strength of colorfulness of images and their types.With such determined information,the algorithm automatically adjusts image colorfulness for a better natural image look.With the help of an additional detection of skin colors and a pixel chroma adaptive local processing,the algorithm produces more natural image look.The algorithm performance had been tested with an image quality judgment experiment of 20 persons.The experimental result indicates a better image preference. 相似文献
33.
Sung-Ook YOON Myoung-Soo KANG Hyun-Bin NAM Yong-Jai KWON Sung-Tae HONG Jin-Chun KIM Kwang-Hak LEE Chang-Yong LIM Jong-Dock SEO 《中国有色金属学会会刊》2012,(Z3):619-623
Friction stir butt welding (FSW) between A5052-O aluminum alloy plates with a thickness of 2 mm was performed.The rotation speeds of the welding tool were 2000 and 3000 r/min,respectively.The traverse speed was ranged from 100 mm/min to 900 mm/min.The defect-free welds with the very smooth surface morphology were successfully obtained,except for at the welding condition of 3000 r/min and 100 mm/min.The onion ring structure was observed in the friction-stir-welded zone (SZ) at the condition of 2000 r/min and 100 mm/min.For all the welding conditions,the grain size of the SZ was smaller than that of the base metal,and was decreased with the decrease of the tool rotation speed and with the increase of the tool traverse speed.The stir zone exhibited higher average hardness than the base metal.The decrease of the tool rotation speed and the increase of the tool traverse speed resulted in the increase in the average hardness of the SZ.The tensile strength of the FSWed plates was similar to that of the base metal,except for at the welding condition of 3000 r/min and 100 mm/min.The total elongation of the FSWed plates was lower than that of the base metal. 相似文献
34.
We realize a vertical channel polymer semiconductor field effect transistor architecture by confining the organic material within gratings of interdigitated trenches. The geometric space savings of a perpendicular channel orientation results in devices sourcing areal current densities in excess of 40 mA/cm(2), using a one-volt supply voltage, and maintaining near-ideal device operating characteristics. Vertical channel transistors have a similar electronic mobility to that of planar devices using the same polymer semiconductor, consistent with a molecular reorientation within confining trenches we understand through X-ray scattering measurements. 相似文献
35.
Chang-Yong Wu Yong-Zhen Peng Xiao-Ling Li Shu-Ying Wang 《Canadian Metallurgical Quarterly》2010,136(11):1248-1254
The effects of acetate and propionate on biological nitrogen and phosphorus removal in a plug-flow A2O process were evaluated in this study. The wastewater quality indexes and operation parameters were the same when different carbon sources were used. However, we observed no obvious effect of carbon source on nitrogen removal. Denitrifying phosphorus removal was found to play an important role in simultaneous nitrogen and phosphorus removal in anoxic reactors because almost the entire carbon source was used for polyhydroxyalkanoate (PHA) synthesis in anaerobic reactors, and there was no external carbon source left for heterotrophic denitrification. Propionate was found to be a more effective and energy-saving carbon source for biological nitrogen and phosphorus removal. In addition, the variations in the metabolic chemicals, such as phosphorus, PHA, glycogen, and oxygen, were lower when propionate was used than when acetate was used. 相似文献
36.
37.
Chang-Yong Lee Won-Bae Lee Jong-Woong Kim Don-Hyun Choi Yun-Mo Yeon Seung-Boo Jung 《Journal of Materials Science》2008,43(9):3296-3304
Lap joint friction stir welding (FSW) between dissimilar 5052-H112 (1 mm) and 6061-T6 (2 mm) Al alloys with different thickness
was carried out with various tool rotation speeds and welding speeds according to the fixed location of each material on bottom
or top sheet. Interface morphology was characterized by pull-up or pull-down from initial joint line. Amount of vertical material
transports increased and thickness of 5052 resultantly lessened with increasing tool rotation and decreasing welding speed,
which were the conditions of the weak bond. Higher stress concentration on the interface pull-up region, the penetration of
unbonded region into the weld zone and the lessened thickness of 5052 Al part might be the reasons for lower fracture load.
Higher fracture load was acquired at the lower tool rotation speed and higher welding speed when a thicker 6061 was fixed
at retreating side on top sheet. Interface morphology was the most important factor determining the mechanical strength of
lap FSW joints and can be manageable using FSW parameters. 相似文献
38.
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
39.
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
40.
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