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	Comments on Mulligan's "Revisiting the urbanization curve" SCI/SSCI论文 OAI收割 2014 Chen M. X.; Ye C.; Zhou Y. 收藏 \| 浏览/下载：22/0 \| 提交时间：2014/12/24 Urbanization curve Upper limit Speed curve Accelerated stage Rapid stage china urbanization
	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：24/0 \| 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 new accurate and fast algorithm of sub-pixel image registration (EI CONFERENCE) 会议论文 OAI收割 2010 IEEE 10th International Conference on Signal Processing, ICSP2010, October 24, 2010 - October 28, 2010, Beijing, China 作者: He B. 收藏 \| 浏览/下载：33/0 \| 提交时间：2013/03/25 In terms of large field view and multi-channel TDICCD remote sensing images previous interpolation methods and curve fitting methods are not able to achieve the high accuracy and fast registration and their noise immunity and robustness is not high. For that this paper presents a more accurate and faster method iterative pixel interpolation and surface fitting method. Firstly the method uses the some overlapping pixels between multi-channel images. Secondly the proposed technique which is based on the maximization of the correlation coefficient function combines an efficient pixel-moving interpolation scheme with surface fitting which makes use of accurate interpolation calculation and fast surface fitting in the iterative process. Finally the accuracy and speed of the algorithm is evaluated by sub-pixel registration of multi-channel images and comparison with other sorts of efficient methods. The experiment results show that the accuracy of the method reaches 0.01 pixels and it is 3 times faster than the interpolation method. In the registration of large field view and multi-channel TDICCD images the method is accurate and fast with greatly high stability noise immunity and robustness. 2010 IEEE.
	Attitude determination of small, dim and high-speed targets based on multi-CMOS intersecting system (EI CONFERENCE) 会议论文 OAI收割 2nd International Conference on Information Science and Engineering, ICISE2010, December 4, 2010 - December 6, 2010, Hangzhou, China 作者: Li M.; Zhao L.; Wang J. 收藏 \| 浏览/下载：37/0 \| 提交时间：2013/03/25 In order to measure attitude of small dim and high-speed targets in shooting range intersecting system based on multiple high-speed CMOS cameras was introduced in this paper. CMOS cameras were laid near from objects for small size using multiple CMOS cameras to compose intersecting system for big number of targets tested and selecting CMOS camera between CMOS and CCD for low cost and considering damage to measurement equipment of objects tested. Pitch angle and yaw angle were measured by extracting axle wire through image processing image sequences were obtained from cameras laying on two sides. Velocity of objects was calculated by least square curve-fitting acquiring coordinate of centroid on image received by CMOS camera laying below effective viewing field. One CMOS camera was laid on right ahead for measuring roll angle. Station mode introduced in this paper has virtue of low cost and free extending. 2010 IEEE.
	Graph fitting test method for the interpolation error of Moire fringe (EI CONFERENCE) 会议论文 OAI收割 9th International Conference on Electronic Measurement and Instruments, ICEMI 2009, August 16, 2009 - August 19, 2009, Beijing, China 作者: Sun Y.; Sun Y. 收藏 \| 浏览/下载：43/0 \| 提交时间：2013/03/25 In order to realize the fast test for the interpolation error the graph fitting test method for the interpolation error of Moire fringe is put forward in this paper. Firstly the triangular wave Moire fringe photoelectric signal of the encoder whose phase difference is 90 are sampled to get the Lissajous graph of the two signals. Secondly the single wave represented by the founded subsection function is used to fit the practical Moire fringe Lissajous graph. Then the fitting result is tested to verify whether it satisfies the accuracy requirement. Lastly the founded subsection function instead of the practical wave function is used to calculate the interpolation error. Using the graph fitting method to sample the Moire fringe single of 15-bits photoelectric encoder to get the interpolation error curve the tested maximum interpolation error is 70" and the minimum error is - 69". Comparing with the interpolation error which is received from traditional test method the change trend of the interpolation error curve is similar and peak-peak value is almost equality. The results of experiment indicate that: the equipment is convenient and the examination method is efficient and feasible. The measure speed is fast and the manifestation result is intuitionistic. The system can be used in the working field. The method can avoid the speed influence and realize the dynamic interpolation error measure which is significant for the research of encoder's dynamic accuracy characteristics. 2009 IEEE.
	Differential Hydrological Grey Model (DHGM) with self-memory function and its application to flood forecasting EI期刊论文 OAI收割 2009 作者: Xia Jun 收藏 \| 浏览/下载：28/0 \| 提交时间：2012/06/11 Curve fitting Hydraulic models Recursive functions Solute transport Speed control