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	Optical fiber marine seismic exploration system feasibility study 期刊论文 OAI收割 ACTA GEOPHYSICA, 2019, 卷号: 67, 期号: 5, 页码: 1403-1411 作者: Wang, Xiangchun; Li, Xueliang; Zhang, Haibing; Hao, Xiaozhu; Yu, Kaiben \| 收藏 \| 浏览/下载：62/0 \| 提交时间：2019/11/14 Fidelity Hydrophones Migration section Optical fiber Signal-to-noise ratio (SNR) Vertical resolution
	New electromagnetic imaging tool introduced for corrosion detection 会议论文 OAI收割 2012 International Conference on Electrical Insulating Materials and Electrical Engineering, EIMEE 2012, Shenyang, Liaoning, China, MAY 25-27, 2012 作者: Zhong XF(钟兴福); Wu YX(吴应湘); Chen JQ; Abakumov A; Zhong XF(钟兴福) 收藏 \| 浏览/下载：26/0 \| 提交时间：2013/02/26 Electrical engineering Electromagnetism Inspection Insulating materials Magnetic leakage Oil fields Brush structure Casing damage Casing wall Corrosion detection Corrosion inspection Electromagnetic imaging High resolution Magnetic flux leakage Metal loss System structures Thickness determination Vertical profile
	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.
	Research on tracking approach to low-flying weak small target near the sea (EI CONFERENCE) 会议论文 OAI收割 ICO20: Optical Information Processing, August 21, 2005 - August 26, 2005, Changchun, China 作者: Xue X.-C. 收藏 \| 浏览/下载：33/0 \| 提交时间：2013/03/25 Automatic target detection is very difficult in complicate background of sea and sky because of the clutter caused by waves and clouds nearby the sea-level line. In this paper in view of the low-flying target near the sea is always above the sea-level line we can first locate the sea-level line and neglect the image data beneath the sea-level line. Thus the noise under the sea-level line can be suppressed and the executive time of target segmentation is also much reduced. A new method is proposed which first uses neighborhood averaging method to suppress background and enhance targets so as to increase SNR and then uses the multi-point multi-layer vertical Sobel operator combined with linear least squares fitting to locate the sea-level line lastly uses the centroid tracking algorithm to detect and track the target. In the experiment high frame rate and high-resolution digital CCD camera and high performance DSP are applied. Experimental results show that this method can efficiently locate the sea-level line on various conditions of lower contrast and eliminate the negative impact of the clutter caused by waves and clouds and capture and track target real-timely and accurately.
	On orbit MTF measurement of remote sensing camera based on wavelet transform (EI CONFERENCE) 会议论文 OAI收割 ICO20: Remote Sensing and Infrared Devices and Systems, August 21, 2005 - August 26, 2005, Changchun, China 作者: Wang X.; Wang X.; Wang X. 收藏 \| 浏览/下载：18/0 \| 提交时间：2013/03/25 High resolution remote sensing images are often applied in many research fields. But there are less research on images quality for an orbit remote sensing camera. The magnitude of the OTF as the modulation transfer function (MTF) is a measure of the 2-D spatial frequency response of the remote sensing camera. In this paper knife-edge technique based on quadratic spline wavelet fast transform algorithm is proposed and applied to generate MTF with a greatly high resolution in horizontal or vertical direction. The result has fully demonstrate the potential applicability and good property of the method to estimate MTF for remote sensing camera.
	Effects of adjusting vertical resolution on the eastern equatorial pacific cold tongue 期刊论文 iSwitch采集 Acta oceanologica sinica, 2005, 卷号: 24, 期号: 3, 页码: 16-27 作者: Wu, FH; Liu, HL; Li, W; Zhang, XH 收藏 \| 浏览/下载：28/0 \| 提交时间：2019/05/10 Ocean general circulation model Vertical resolution Eastern equatorial pacific ocean Cold tongue