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	Flow-Sediment Interaction and Formation Mechanism of Sediment Longitudinal Streaky Structures in Rough Channel Flows 期刊论文 OAI收割 JOURNAL OF HYDRAULIC ENGINEERING, 2025, 卷号: 151, 期号: 1, 页码: 17 作者: Wang, Hao; Kong, Xiangju; Zhong, Qiang \| 收藏 \| 浏览/下载：4/0 \| 提交时间：2025/03/03 Longitudinal sediment streaks Streamwise vortex Movement characteristic Bed structure Formation mechanism
	The Research of real time auto-recognition of the moire fringe (EI CONFERENCE) 会议论文 OAI收割 International Symposium on Photoelectronic Detection and Imaging 2011: Advances in Imaging Detectors and Applications, May 24, 2011 - May 26, 2011, Beijing, China Wang M.-J.; Wu Z.-G. 收藏 \| 浏览/下载：19/0 \| 提交时间：2013/03/25 Measuring the movement of raster by the method of moire fringe has the advantage of high sensitivity high resolution and non-contacted measurement. The characteristic of moire fringe is that the image is white alternate with black the angle of the stripes is uniform the width of the stripes is uniform the terminators of the stripes aren't clear. A fast method that can figure out the width and angle of the moire fringe precisely is put forward in this paper. It calculates the angle the stripes firstly. According to the principle of the minimum mean squared error (MMSE) the closer a series of data is the smaller the value of the MMSE will be. The method is described as follows: It takes the image's center as the origin 180 beelines pass through the origin with the same angle interval. it calculates the value of the minimum mean squared error of the 180 beelines and find out the least one among those then the angle of the moire fringe comes out primarily. In order to improving the calculating precision of moire fringe 60 equal angles are divided in the neighborhood of the angle then a precise angle of moire fringe is calculated according to the principle of the MMSE. After getting out the angle of the moire fringe we begin to calculate the width of moire fringe. A line vertical with the moire fringe is drawn and we can get the width of the moire fringe by the vertical line. In order to get over the influence of the noise an effective area with the shape of diamond is selected in the image. The data of area is accumulated and projected according to the direction of moire fringe and a sine curve come out. The width of moire fringe can be obtained by getting the position of the first wave crest the position of the last wave crest and the number of wave crest. Experiments prove that the precision of the method put forward in this paper is enhanced in comparison with the traditional frequency method the precision of width calculation achieves to 99.6% according to the evaluation indicators of width detection error. The computing speed is boosted largely compared with traditional method and it can achieve with 15 ms that satisfying the demand of real time. 2011 SPIE.
	A real-time two-dimensional correlation speed measurement based on image (EI CONFERENCE) 会议论文 OAI收割 2010 International Conference on Computer, Mechatronics, Control and Electronic Engineering, CMCE 2010, August 24, 2010 - August 26, 2010, Changchun, China 作者: Yu L. 收藏 \| 浏览/下载：23/0 \| 提交时间：2013/03/25 In order to implement two-dimensional moving object's non-contact and real-time speed measurement in this paper wc proposed a new method which was based on the characteristic of FPGA and a real-time two-dimensional correlation speed measurement was proposed on image processing using high speed CMOS shown in figure 1. Experimental installation was shown in figure 2 a cardboard with images which was fixed in electric control movement device was moving to simulate moving object the CMOS image sensor gathered image signals of the cardboard and the image signals was output to FPGA after a serials pretreatment such as binaryzation etc. Logical operation insteaded mathematical operation on FPGA to implement two frames image's cross-correlation operations as the formula (10) in this paper and finally calculate the two-dimensional velocity. Through experiment result of table 1 we drawn an conclusion the accurarcy of the method in this paper was less than 1 pixel and the method can be used at a certain speed ranges of two-dimensional real-time speed measurement. 2010 IEEE.
	Random noise filtering technology of piezoelectricity gyro (EI CONFERENCE) 会议论文 OAI收割 2010 International Conference on Computer, Mechatronics, Control and Electronic Engineering, CMCE 2010, August 24, 2010 - August 26, 2010, Changchun, China Qingjun L.; Yongming Y. 收藏 \| 浏览/下载：34/0 \| 提交时间：2013/03/25 Inertia sensing elements are usually adopted as the sensors of velocity stabilization loop in airborne photoelectric equipments therefore we need to adopt filtering processing to reduce influence to control system. In this paper which are constituted stabilized control system we analyze the characteristic of noise gyro drift that purpose is reducing the influence of the movement of carrier to visual axis of photoelectric probing system. But gyro and utilize Kalman filtering technology to conduct filtering processing to output signal of gyro especially the piezoelectricity gyro generates drift this method can reduce output noise effectively. The simulation results show that the proposed filtering processing method can improve the low velocity characteristic. 2010 IEEE. which is the main error source of photoelectric stabilized control system