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	The optical design of cubic phase plate testing system (EI CONFERENCE) 会议论文 OAI收割 2011 Symposium on Photonics and Optoelectronics, SOPO 2011, May 16, 2011 - May 18, 2011, Wuhan, China 作者: Zhang X.; Zhang X.; Zhang X.; Zhang Y. 收藏 \| 浏览/下载：19/0 \| 提交时间：2013/03/25 Computer-generated holograms (CGH) have been widely used for years in optical testing of aspheric surfaces in combination with Fizeau interferometers. With the development of diffraction optics computer technology and micro-processing technology the accuracy of the CGH testing can achieve a hundredth of a wave and the cost is reduced greatly. CGH is capable of producing an optical wavefront with any desired shape. So it is fascinating and will have good prospects to test free-form surfaces using CGH. As the CGH can create any wavefront shape it can also be used in unsymmetrical aspherical surfaces testing. Taking the cubic surface as an example this paper gives a method to test unsymmetrical surfaces. This paper gives the design to test a cubic surface. And the separation of the diffraction orders and the binary process of the continuous CGH phase function are discussed in detail. The alignment tolerance of the test system and the CGH fabrication tolerance are analyzed. We also present an idea using a CGH and two spherical lenses as null lens to test the cubic surface when the surface deviation is great. 2011 IEEE.
	Parameter identification of airborne vibrated image based on high-speed CCD (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 Shi J.; Xue X.; Guo Y. 收藏 \| 浏览/下载：33/0 \| 提交时间：2013/03/25 In order to identify the vibration parameters of a vibrated image the principle and shortage of the traditional methods that based on image derivative and image transformation are analyzed and a new parameter identification method is proposed afterward. By placing a high-speed CCD aside the master CCD the vibration can be sampled accurately and more information can be obtained for parameter identification. The series frames that captured by high-speed CCD are processed by gray projection algorithm and the vibration extents between adjacent frames along x and y direction are obtained. By using simple triangle operations the vibration parameters can be identified and the computational complexity of which can be reduced greatly. The experiment shows that the parameter identification method based on high-speed CCD can identify the parameters of vibration with any form accurately. The precise of parameter identification for linear vibration is less than 2.95%. 2010 IEEE.
	Symmetry Groups and Exact Solutions of New (4+1)-Dimensional Fokas Equation 期刊论文 OAI收割 COMMUNICATIONS IN THEORETICAL PHYSICS, 2009, 卷号: 51, 期号: 5, 页码: 876-880 作者: Yang Zheng-Zheng; Yan Zhen-Ya \| 收藏 \| 浏览/下载：13/0 \| 提交时间：2018/07/30 Fokas equation point symmetry potential symmetry solitary wave solution reduced form
	High speed, low memory image coding using zero blocks of wavelet coefficients (EI CONFERENCE) 会议论文 OAI收割 4th International Conference on Image and Graphics, ICIG 2007, August 22, 2007 - August 24, 2007, Chengdu, China 作者: Zhang T.; Yang W.-G. 收藏 \| 浏览/下载：33/0 \| 提交时间：2013/03/25 We propose a new high speed low memory SPECK image coder based on the form of block-unit states called LBUS-SPECK which uses the form of block-unit states and the form of block exponents to substitute LIS and LSP of SPECK. A form of block-unit states is introduced to store the significance flag of coefficients and the value of the block-unit exponents. A form of block exponents is introduced to store the block exponents which are used to represent the max coefficient in a decomposed block. A new block depth-finding strategy is developed for searching insignificant sets at sorting stage. Experimental results show that the obtained PSNR values for the decoded images are very close to those of SPECK algorithm and the memory consumption is reduced by 9 times the encoding timing is saved about 15%. Comparing with SPECK algorithm this algorithm not only has better performance of the decoded images but also is easy to implement especially it provides an efficient way for hardware implementation of wavelet embedded block coding. 2007 IEEE.