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ADMM-based Distributed Algorithm for Economic Dispatch in Power Systems With Both Packet Drops and Communication Delays 期刊论文  OAI收割
IEEE/CAA Journal of Automatica Sinica, 2020, 卷号: 7, 期号: 3, 页码: 842-852
作者:  
Qing Yang;  Gang Chen;  Ting Wang
  |  收藏  |  浏览/下载:28/0  |  提交时间:2021/03/11
Large eddy simulation of unsteady shedding behavior in cavitating flows with time-average validation 期刊论文  OAI收割
Ocean Engineering, 2016, 卷号: 125, 页码: 1-11
作者:  
Li LM(李林敏);  Li BK(李宝宽);  Hu ZQ(胡志强);  Lin Y(林扬);  Cheung, Sherman C.P.
收藏  |  浏览/下载:23/0  |  提交时间:2016/09/17
Efficient rate control technique for CCSDS image encoding (EI CONFERENCE) 会议论文  OAI收割
IEEE 2nd International Conference on Computing, Control and Industrial Engineering, CCIE 2011, August 20, 2011 - August 21, 2011, Wuhan, China
Jin L.
收藏  |  浏览/下载:101/0  |  提交时间:2013/03/25
For the limitation of data transmission bandwidth and real time transmission demand  generally image compression is required to implement the precise and flexible rate control algorithm. Rate control is an important issue in the image compression field. This paper considers the problem of rate allocation to each encoded segment for CCSDS image compression. One straightforward method is to allocate an equal amount of rate to each segment based on the average of the total number of compressed bytes. The obvious drawback of this method is that different segment will be reconstructed to different quality  so the overall quality of the reconstructed image will not be optimized. For the shortage of the original rate control method  as to improve the overall quality of the reconstructed image  an improved rate control algorithm is proposed for CCSDS image encoding. The key component of the proposed rate control method is the appropriate rate allocation. Experiments on the test images show that the PSNR can be increased at about 0.3dB on average  compared to the original algorithm. Therefore  experimental results confirm the effectiveness of the proposed algorithm in terms of objective evaluation  and the rate-distortion performance of the reconstructed image is improved. 2011 IEEE.  
The research of the accurate measure of static transfer function for the TDI CCD camera (EI CONFERENCE) 会议论文  OAI收割
3rd International Photonics and OptoElectronics Meetings, POEM 2010, November 2, 2010 - November 5, 2010, Wuhan, China
Guo-Ning L.; Long-Xu J.; Jian-Yue R.; Wen-Hua W.; Shuang-Li H.
收藏  |  浏览/下载:28/0  |  提交时间:2013/03/25
In the test course of static transfer function of TDI CCD camera  because of the influence that gets environmental and artificial etc. factor  the value of static transfer function measured at any time is between unceasing fluctuation  so  make accuracy reduce. To solve this problem  a kind of accurate measurement technique of static transfer function is put forward. First  before carrying out the measure of static quiet of transfer function  the best test point of transfer function of the TDI CCD camera must be determined  it is parallel to guarantee the rectangle target surface of parallel optical pipe and camera focal plane maintenance parallel  and again guarantee target strip in rectangle target and TDI CCD in camera focal plane maintenance vertical. TDI CCD catches rectangle target image  per 1000 lines of target mark image as a measures sample of static transfer function  exclude because of atmosphere tremble twisted  vague rectangle target mark image  retain 500 distinct and steady target mark image as measure sample set. Then  calculate the static transfer function of each measure sample respectively  take the average of all static quiet transfer function in measure sample set as the static transfer function of camera. Finally  the measure of the static transfer function for TDI CCD camera makes error analysis. Experimental results indicate that the value of the static transfer function of TDI CCD camera measured with this kind of method is 0.2923  with before measurement technique comparison  the value of static transfer function has raised 0.02  makes the accuracy of the measure of static transfer function have gotten raising.  
Modulation transfer function in seeker camera limits resulting from missile flutter caused by aerodynamic force (EI CONFERENCE) 会议论文  OAI收割
2010 2nd International Conference on Industrial Mechatronics and Automation, ICIMA 2010, May 30, 2010 - May 31, 2010, Wuhan, China
作者:  
Zhang X.;  Zhang X.;  Zhang X.
收藏  |  浏览/下载:29/0  |  提交时间:2013/03/25
The imaging quality of seeker in flight mode has been evaluated through analyzing the effects of missile flutter on optical modulation transfer function (MTF) of the optical system. Firstly the data of transverse vibration has been processed to eliminate the trend term caused by the trajectory  then obtained the displacement with two times trapezoidal integration. For the side rotation  the high frequency noise interference in the data has been filtered by using five-point moving average method. Took this model as the quivering rule between the object and the image  and then analyzed the effects of the transverse vibration and the side rotation on imaging quality through MTF. By calculation  the r.m.s value of the image motion caused by missile transverse vibration is 0.026mm  and the side rotation angle is 0.0044 . Through the establishment of two modulation transfer functions (MTF) of image random vibration and linear vibration  the results show that the image quality had declined  and the effect of transverse vibration on image quality is obvious. Through improving the rigidity of the missile and selection of small focal length optical system and shorten the time of exposure can improve the imaging quality of the seeker. 2010 IEEE.  
The research for missile bullets' multiple targets of opto-electronic theodolites (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
Wei Z.; Liu Y.-H.
收藏  |  浏览/下载:47/0  |  提交时间:2013/03/25
The system of opto-electronic theodolites for measuring missile bullet provides parameter of missile bullet trajectory and affords primacy scientific data for completing campaign assign and obtaining ideal result of destroy. This article researches extraction arithmetic for missile bullet' multiple targets. Above all  enactment threshold of area  acquire middle axes of target by adopting Hough transforming and approximating and calculate obliquity angles of targets. In course of matching  accomplish missile bullet's multiple targets data association of serial images by making use of improving eigenfunction and achieve extraction of missile bullet's multiple targets after obtaining center position of targets  adopting OSTU method change numeral image into binary image  according to area of target  forecast searching region of target matching by using Kalman filter  area of targets  and abstract separately center position of targets and area of targets  judge conglutination and obstruct  then separate targets in term of wave crest and trough's variety of grey histogram of conglutination region  grey average of target and obliquity angles of targets. The experimental result shows that right ratio of the extraction targets reach to 90%. The article use correct mathematical model and reasonable arithmetic and obtain effectively parameter of missile bullet' multiple targets. 2010 IEEE.  at the same time  obtain grey average of target  mark target region  
Rigorous vector analysis of diffractive microlens by using of finitedifference time-domain method (EI CONFERENCE) 会议论文  OAI收割
2009 International Conference on Optical Instruments and Technology, OIT 2009, October 19, 2009 - October 22, 2009, Shanghai, China
作者:  
Liu Y.;  Liu H.;  Liu H.;  Liu H.;  Liu Y.
收藏  |  浏览/下载:36/0  |  提交时间:2013/03/25
We use finite difference time domain (FDFD) method as rigorous vector analysis model to simulate the focusing process of diffractive microlens (DML). Differing with most analysis model which the near field distributions are calculated by FDTD and then far field are obtained by using of propagation method  we obtain the fields in whole computational space by using of FDTD only. The advantages are that all the results are vector based and the computational time is saved greatly. In this paper  we present two methods to obtain wave amplitude  one is comparison method  and the other is integral method. Depending on wave amplitude in the whole computational space  one can conveniently obtain distributions of electric field intensity and calculate the time-average Poynting vector. We also present the formulation for calculating diffractive efficiency of DML based on time-average Poynting vector which denotes energy flow. As demonstration  a DML is analyzed by using of these algorithms. The time depended graphic results of FDTD show the process of wave propagation. The distribution of electric field intensity illustrates the focusing of the normal incident light. The focus pattern in the focal plane is also show. The diffractive efficiency of the DML is calculated by using of the energy flow method in this paper. The results show the high accuracy and efficiency of the model. 2009 SPIE.