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	Performance of the White method for estimating groundwater evapotranspiration under conditions of deep and fluctuating groundwater SCI/SSCI论文 OAI收割 2016 作者: Zhang P.; Yuan, G. F.; Shao, M. A.; Yi, X. B.; Du, T. 收藏 \| 浏览/下载：35/0 \| 提交时间：2016/12/16 groundwater evapotranspiration the White method specific yield recharge rate of groundwater desert riparian forest deep groundwater depth water-table fluctuations lower tarim river level fluctuations riparian zone lower reaches desert china environments vegetation xinjiang
	Performance of the White method for estimating groundwater evapotranspiration under conditions of deep and fluctuating groundwater 期刊论文 OAI收割 HYDROLOGICAL PROCESSES, 2016, 卷号: 30, 期号: 1, 页码: 106-118 作者: Zhang, P; Yuan, GF; Shao, MA; Yi, XB; Du, T \| 收藏 \| 浏览/下载：13/0 \| 提交时间：2018/04/14 groundwater evapotranspiration the White method specific yield recharge rate of groundwater desert riparian forest deep groundwater depth
	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.
	White-light spectral scanning interferometry for surface measurement system (EI CONFERENCE) 会议论文 OAI收割 6th International Symposium on Precision Engineering Measurements and Instrumentation, August 8, 2010 - August 11, 2010, Hangzhou, China 作者: Wang C. 收藏 \| 浏览/下载：27/0 \| 提交时间：2013/03/25 The paper introduces the white-light spectral scanning interferometry for surface measurement. This interferometry can be used to measure the roughness of both smooth surfaces and those with large step heights. This real-time surface measurement can be achieved using acousto-optic tuneable filtering (AOTF) technique without mechanical scanning. At first the structure and principle of this interferometry is introduced. Then the algorithm of the surface roughness measurement is proposed. What's more the experiment with standard test piece is conducted. Compared with the traditional laser-light interferometry the data shows that the proposed method has a higher accuracy which is proved to be nano-scale. A conclusion is given at last in which the superiorities and the limitations of the proposed system were discussed. 2010 SPIE.
	Phase error estimation with broadband white light by Phase Diversity (EI CONFERENCE) 会议论文 OAI收割 6th International Symposium on Precision Engineering Measurements and Instrumentation, August 8, 2010 - August 11, 2010, Hangzhou, China 作者: Wang Z.; Wang B.; Zhang X.; Zhang X.; Zhang X. 收藏 \| 浏览/下载：19/0 \| 提交时间：2013/03/25 The technique of Phase Diversity (PD) is widely adopted to measure the wavefront error caused by atmosphere turbulence and system error. PD solves the Zernike coefficients of the wavefront by utilizing two images obtained with different defocus value. In this paper we propose a method to restore the image and estimate the wavefront error of an imaging system. And we use present white noises to verify the robustness of the algorithm. We design an experiment system and implement it in our laboratory. The proposed algorithm is validated by computer simulations and experimental results. To use a broadband white object in experimental system a reasonable simplification for the system model is done. Our results show that the robustness against Gaussian white noises of the method is better then the case when the variance value is 0.03. The proposed method can be used as a wavefront sensor and restore the degradative images by photoelectric image system. 2010 SPIE.
	Study of unequal error protection method based on JPEG2000 for surveyingmapping image (EI CONFERENCE) 会议论文 OAI收割 International Conference on Computer Science and Software Engineering, CSSE 2008, December 12, 2008 - December 14, 2008, Wuhan, Hubei, China Yao Q.; Cao M. 收藏 \| 浏览/下载：163/0 \| 提交时间：2013/03/25 On aviation mapping compression image maybe not decode because of wireless transmission interference. UEP(Unequal Error Protection) scheme is put forward about layer and block structure of JPEG2000 image compression method flexibly enhances local reconfigurable image's quality which is in favor of identifier in the region of interest. 2008 IEEE. and realizes three degrees UEP of data block data header image data via various degrees correction-coding under the condition of obstruct naked and shade. BCH RS and Hamming coding are simulated and image decoding success rate and image's quality are analyzed according to different coding and ROI (Region of Interest) in the Gaussian white noise model and rayleigh fading model. Results shows that the method we putted forward roughly improves decoding success rate at the same time almost not increasing bandwidth
	Displacement estimation by the phase-shiftings of fourier transform in present white noise (EI CONFERENCE) 会议论文 OAI收割 ICO20: Optical Information Processing, August 21, 2005 - August 26, 2005, Changchun, China 作者: Wu Y.-H. 收藏 \| 浏览/下载：29/0 \| 提交时间：2013/03/25 Displacement estimation is a fundamental problem in Real-time video image processing. It can be typically approached by theories based on features in spatial domain. This paper presents an algorithm which improves the theory for estimating the moving object's displacement in spatial domain by its Fourier transform frequency spectrum. Because of the characters of Fourier transform the result is based on all the features in the image. Utilizing shift theorem of Fourier transform and auto-registration the algorithm employs the phase spectrum difference in polar coordinate of two frame images sequence with the moving target1 2. The method needn't transform frequency spectrum to spatial domain after calculation comparing with the traditional algorithm which has to search Direc peak and it reduces processing time. Since the technique proposed uses all the image information including all the white noise in the image especially and it's hard to overcome the aliasing from noises but the technique can be an effective way to analyze the result in little white noise by the different characters between high and low frequency bands. It can give the displacement of moving target within 1 pixel of accuracy. Experimental evidence of this performance is presented and the mathematical reasons behind these characteristics are explained in depth. It is proved that the algorithm is fast and simple and can be used in image tracking and video image processing.