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	Effects of process parameters on the spreading morphology of disc surface and aluminium powder produced by centrifugal atomisation 期刊论文 OAI收割 POWDER METALLURGY, 2023 作者: Li L(李龙); Peng L(彭磊); Zhao W(赵伟) \| 收藏 \| 浏览/下载：15/0 \| 提交时间：2023/07/17 Centrifugal atomisation rotary disc spreading morphology aluminium powder particle size distribution median diameter
	Research on Internal-Mixing Nozzle for the Icing Environment Simulation 会议论文 OAI收割 Applied Mechanics and Materials I, Pts 1-3, Stafa-Zurich Xu, Liuqing; Liu, Haili; Zhang, Fengquan; Guo, Lili 收藏 \| 浏览/下载：19/0 \| 提交时间：2014/12/07 internal-mixing nozzle median volume diameter inner flow field external flow field
	Channel change at toudaoguai station and its responses to the operation of upstream reservoirs in the upper yellow river 期刊论文 iSwitch采集 Journal of geographical sciences, 2010, 卷号: 20, 期号: 2, 页码: 231-247 作者: Ran Lishan; Wang Suiji; Fan Xiaoli 收藏 \| 浏览/下载：36/0 \| 提交时间：2019/05/10 Cross-sectional profile Median diameter Reservoir Toudaoguai cross-section The upper yellow river
	Far-field focusing of laser beam based on digital image processing techniques (EI CONFERENCE) 会议论文 OAI收割 Optoelectronic Imaging and Multimedia Technology, October 18, 2010 - October 20, 2010, Beijing, China 作者: Zhao S.; Tian Y.-Z.; Liu L.-S.; Guo J.; Zhang H.-Y. 收藏 \| 浏览/下载：26/0 \| 提交时间：2013/03/25 In order to lead the laser beam transmit in the atmosphere convergently an experiment of laser focus at the distance of 450m and 300m has been operated in the outdoor place. The actual manipulations are as follows: Firstly the laser was collimated by a beam expander then the near-parallel laser beam was transmitted with a Galileo telescope system and the distance between the concave lens and the convex lens can be tuned through a precise displacement platform so the focus of the system changed due to the tiny displacement of the concave lens. Secondly the average power of the laser spot can be measured using power meter the power is 47.67mW and the standard deviation is 0.67mW while the focal length is 450m. Thirdly the energy distribution was found through the laser beam analyzer. The spot images were saved using the beam analyzer then the saved image can be processed with Matlab software afterwards. The function named EDGE and Sobel operator was used in the pre-processing of the saved image then method of median filter was used in the course of image de-noising and 53H filter was adopted in the signal analysis. The diameter of laser spot was obtained by the method above the diameter is 5.56mm and the standard deviation is 0.24mm. The spot center excursion is 0.56mm it is 10.43% of the total diameter of the laser spot. At last the key factors of the energy dissipation in the focusing system can be summarized as follows: restriction of the diffraction limit attenuation in the atmosphere geometrical aberration of optical system and the diffraction limit and the geometrical aberration are significant in the three factors above so we can reduce the impact of the both factors during the design of optical system. The reliable referenced data of the system design can be acquired through the primary experiment research. 2010 SPIE.
	Channel change at Toudaoguai Station and its responses to the operation of upstream reservoirs in the upper Yellow River SCI/SSCI论文 OAI收割 2010 Ran L. S.; Wang S. J.; Fan X. L. 收藏 \| 浏览/下载：33/0 \| 提交时间：2012/06/08 cross-sectional profile median diameter reservoir Toudaoguai cross-section the upper Yellow River sediment load downstream dams impacts example basin texas flow