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Image Encryption Application of Chaotic Sequences Incorporating Quantum Keys 期刊论文  OAI收割
International Journal of Automation and Computing, 2020, 卷号: 17, 期号: 1, 页码: 123-138
作者:  
Bin Ge;  Hai-Bo Luo
  |  收藏  |  浏览/下载:33/0  |  提交时间:2021/02/22
Cycloartane and Friedelane Triterpenoids from the Leaves of Caloncoba glauca and Their Evaluation for Inhibition of 11 beta-Hydroxysteroid Dehydrogenases 期刊论文  OAI收割
JOURNAL OF NATURAL PRODUCTS, 2012, 卷号: 75, 期号: 4, 页码: 599-604
作者:  
Mpetga, James D. Simo;  Shen, Yu;  Tane, Pierre;  Li, Shi-Fei;  He, Hong-Ping
收藏  |  浏览/下载:44/0  |  提交时间:2012/06/07
The new approach for infrared target tracking based on the particle filter algorithm (EI CONFERENCE) 会议论文  OAI收割
International Symposium on Photoelectronic Detection and Imaging 2011: Advances in Infrared Imaging and Applications, May 24, 2011 - May 24, 2011, Beijing, China
作者:  
Sun H.;  Han H.-X.;  Sun H.
收藏  |  浏览/下载:79/0  |  提交时间:2013/03/25
Target tracking on the complex background in the infrared image sequence is hot research field. It provides the important basis in some fields such as video monitoring  precision  and video compression human-computer interaction. As a typical algorithms in the target tracking framework based on filtering and data connection  the particle filter with non-parameter estimation characteristic have ability to deal with nonlinear and non-Gaussian problems so it were widely used. There are various forms of density in the particle filter algorithm to make it valid when target occlusion occurred or recover tracking back from failure in track procedure  but in order to capture the change of the state space  it need a certain amount of particles to ensure samples is enough  and this number will increase in accompany with dimension and increase exponentially  this led to the increased amount of calculation is presented. In this paper particle filter algorithm and the Mean shift will be combined. Aiming at deficiencies of the classic mean shift Tracking algorithm easily trapped into local minima and Unable to get global optimal under the complex background. From these two perspectives that "adaptive multiple information fusion" and "with particle filter framework combining"  we expand the classic Mean Shift tracking framework.Based on the previous perspective  we proposed an improved Mean Shift infrared target tracking algorithm based on multiple information fusion. In the analysis of the infrared characteristics of target basis  Algorithm firstly extracted target gray and edge character and Proposed to guide the above two characteristics by the moving of the target information thus we can get new sports guide grayscale characteristics and motion guide border feature. Then proposes a new adaptive fusion mechanism  used these two new information adaptive to integrate into the Mean Shift tracking framework. Finally we designed a kind of automatic target model updating strategy to further improve tracking performance. Experimental results show that this algorithm can compensate shortcoming of the particle filter has too much computation  and can effectively overcome the fault that mean shift is easy to fall into local extreme value instead of global maximum value.Last because of the gray and fusion target motion information  this approach also inhibit interference from the background  ultimately improve the stability and the real-time of the target track. 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).  
Estimation algorithm of mobile OFDM CFOs based on step-size (EI CONFERENCE) 会议论文  OAI收割
2009 International Conference on Information Engineering and Computer Science, ICIECS 2009, December 19, 2009 - December 20, 2009, Wuhan, China
Lin L.; Qiao Y.-F.; Su W.-X.
收藏  |  浏览/下载:56/0  |  提交时间:2013/03/25
In order to maintain orthogonality among subcarriers for mobile OFDM  a CFOs step-size estimation model is established to avoid severe performance degradation caused by ICI  and algorithmic stability  step-size parameter  the error of CFOs estimate and etc are investigated. First  after an averaging window algorithm is introduced  the mathematic model of step-size estimation algorithm is obtained through step-size parameter and time-varying CFOs. Then  based on the results of MATLAB simulation  the determination of step-size parameter  the advantages of step-size algorithm and precision are discussed. Finally  time sequence plots of added CP  interleaver and subcarrier modulation with VHDL are presented. Experimental results indicate that the maximum of CFOs errors is 0.00987 in 3 variance interval  when mobile velocity is 400 km/h  according with verdicted principle that in order for the ICI effects to be negligible  the error of CFOs estimation must be accurate within 1-2% of the subcarrier spacing  and programs can correctly implement on circuit board. 2009 IEEE.  
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:43/0  |  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.