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	The design problems of one kind of chaotic one-way hash function (EI CONFERENCE) 会议论文 OAI收割 2012 4th International Conference on Multimedia and Security, MINES 2012, November 2, 2012 - November 4, 2012, Nanjing, Jiangsu, China Li P.; Zhang M.; Shi J. 收藏 \| 浏览/下载：26/0 \| 提交时间：2013/03/25 The construction method of one kind of one-way hash function based on 1-D Logistic map is analyzed. The design problem and some collision problems are pointed out. By using the dictionary attack the collision probability of the arithmetic realized with signal floating point numbers is 2-23 and the collision probability of the arithmetic realized with double floating point numbers is 2-55. The reasons for these design problems are discussed and some key problems are pointed out which should be taken care of while constructing one-way hash function based on a digital chaotic map. 2012 IEEE.
	Image compression based on contourlet and no lists SPIHT (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: Zhang S. 收藏 \| 浏览/下载：52/0 \| 提交时间：2013/03/25 The volume of raw image data captured by the high resolution camera is extremely huge. Thus the efficient image compression method should be used to decrease the bit rate. The image compression method based on wavelet is used more widely nowadays. However two dimensional wavelet is only the tensor product of the one dimensional wavelet whose support region of basis function is extended from interval to square. Contourlet is an image multiscale geometric analysis tool which could represent image sparsely and has strong capability of nonlinear approximation. The basis function of contourlet is multidirectional and anisotropic. Nevertheless contourlet is redundant. So the non-redundant Wavelet Based Contourlet Transform (WBCT) is used in this paper. The SPIHT algorithm is very efficient way to coding the significant coefficients. And the improved no lists SPIHT is more easy to implemented by hardware. Image compression method based on the combination of both wavelet based contourlet transform and no lists SPIHT coding is proposed in the paper. Experiment shows that compared to wavelet based scheme the contourlet scheme can reserve the texture of the image. For barbara test image when coding at low bit rate the PSNR can improve about 0.2dB. 2010 IEEE.
	The parallel computation in one-way hash function designing (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: Yang H. 收藏 \| 浏览/下载：22/0 \| 提交时间：2013/03/25 In order to put the parallel one-way hash function into engineering two designing models based on pipeline technology are proposed in this paper. The definition of one-way hash function is shown first and the structure and limitation of the current hash functions are discussed afterward. By analyzing the difference between parallel computation on different platforms and classifying one-way hash functions on application basis the possibility and method of parallel one-way hash function designing on different hardware platforms are described two designing models are constructed for the parallel one-way hash function designing. Finally some attentions for designing are proposed from the engineering angle. The pipeline models that proposed in this paper contact the theoretical rationality and the engineering application of parallel one-way hash function together which can improve the practicality of parallel one-way hash function to a great extent. 2010 IEEE.
	Design and image restoration research of a cubic-phase-plate system (EI CONFERENCE) 会议论文 OAI收割 5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Advanced Optical Manufacturing Technologies, April 26, 2010 - April 29, 2010, Dalian, China 作者: Zhang J.; Zhang J.; Zhang J.; Shi G.; Zhang X. 收藏 \| 浏览/下载：30/0 \| 提交时间：2013/03/25 Wave-front coding technology is a novel jointly optical and digital imaging technology which can greatly extend the depth of focus of optical systems. The image restoration process is an important part of wave-front coding technology. Using wave-front coding makes the modulation transfer function(MTF) values of the optical systems change little over a range of several times the depth of focus which means the system MTF is quite insensitive to defocus and there is no zero in the passband. So we can design a single filter for the restoration of images in different defocus positions. However it's hard to avoid noise during image acquisition and transmission processes. These noises will be amplified in the image restoration especially in the high frequency part when the MTF drop is relatively low. The restoration process significantly reduces the system signal to noise ratio this way. Aimed at the problem of noise amplification a new algorithm was proposed which incorporated wavelet denoising into the iterative steps of Lucy-Richardson algorithm. Better restoration results were obtained through the new algorithm effectively solving the noise amplification problem of original LR algorithm. Two sets of identical triplet imaging systems were designed in one of which the cubic-phase-plate was added. Imaging experiments of the manufactured systems were carried and the images of a traditional system and a wave-front coded system before and after decoding were compared. The results show that the designed wave-front coded system can extend the depth of focus by 40 times compared with the traditional system while maintaining the light flux and the image plane resolution. 2010 Copyright SPIE - The International Society for Optical Engineering.
	Modulation transfer function measurement of sampled imaging systems in field test (EI CONFERENCE) 会议论文 OAI收割 5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optical Test and Measurement Technology and Equipment, April 26, 2010 - April 29, 2010, Dalian, China 作者: Yang L.; Zhang J.; Zhang J.; Zhang J.; Wang J. 收藏 \| 浏览/下载：36/0 \| 提交时间：2013/03/25 A digital mirror device (DMD) based light projector was developed as the target generator in modulation transfer function (MTF) measurement. In order to overcome the sampling-scene phase effect in MTF measurement of sampled imaging systems a method using random targets is introduced to yield a phase-averaged MTF. The main potential problem of implementing this method is the fact that the stationary assumption of the random targets may be vitiated in practical measurement especially in field test due to the ill condition. We provide an efficient model-independent way of analyzing and isolating the spectral contents arising from these additional contributions to MTF measurement. Algorithms with adaptive parameter selection were also developed for spectral estimation of the test image in order to overcome the challenge brought by the size limit of the test matrices for one certain field of view derived from the isoplantic region. The MTF measurement of a CCD video imager is used to demonstrate the measurement technique and illustrate the benefits over other methods. In order to validate the results comparisons have been made between MTF measurements of imager implemented using this method and bar target direct measurements. 2010 Copyright SPIE - The International Society for Optical Engineering.
	A framework for real-valued cipher systems 期刊论文 OAI收割 JOURNAL OF SYSTEMS SCIENCE & COMPLEXITY, 2007, 卷号: 20, 期号: 4, 页码: 486-491 作者: Zhang, Zhaozhi; Jiang, Nan \| 收藏 \| 浏览/下载：17/0 \| 提交时间：2018/07/30 computational complexity theory digital one-way function general one-way function real-valued cipher system
	有界单向函数的通用求逆算法研究期刊论文 OAI收割计算机学报, 2006, 卷号: 29, 期号: 9, 页码: 1603-1607 薛锐; 刘吉强 \| 收藏 \| 浏览/下载：19/0 \| 提交时间：2011/07/13 密码学单向函数有界单向函数可忽略函数求逆算法 cryptography one way function bounded one-way function negligible functions inverting algorithm 通用存在性成功概率 computer science 正整数算法 open problem 计算机科学 NP problem 密码系统依赖性困难性设计基础概念
	Implement of optimal separable approximation in seismic migration 期刊论文 OAI收割 CHINESE JOURNAL OF GEOPHYSICS-CHINESE EDITION, 2005, 卷号: 48, 期号: 6, 页码: 1422-1427 作者: Zhang, ZF; Liu, H; Chen, JB; Li, YM \| 收藏 \| 浏览/下载：23/0 \| 提交时间：2018/09/26 Optimal Separable Approximation One-way Wave Operator Characteristic Function Migration