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Measurement of TOF of fast neutrons with U-238 target 期刊论文  OAI收割
NUCLEAR ENGINEERING AND TECHNOLOGY, 2021, 卷号: 53, 期号: 6, 页码: 1964-1969
作者:  Li, Meng;  Guan, Yuanfan;  Lu, Chengui;  Zhang, Junwei;  Yuan, Xiaohua
  |  收藏  |  浏览/下载：40/0  |  提交时间：2021/12/09
Image mosaic technique based on the information of edge (EI CONFERENCE) 会议论文  OAI收割
2012 3rd International Conference on Digital Manufacturing and Automation, ICDMA 2012, July 31, 2012 - August 2, 2012, Guilin, Guangxi, China
作者:  Wang Y.-Q.
收藏  |  浏览/下载：33/0  |  提交时间：2013/03/25
Image mosaic is an important branch in the field of image processing. This paper designs and realizes an image mosaic technique based on the information of edge. The technology is suitable for engineering application. First of all  two images of the adjoining frames are processed by convolution operation  get the edge images. And then we cut edge image into pieces and compute their spatial frequency. According to the value of the spatial frequency select reasonable registration model group. We compute correlation strength and the value of movement offset which are the model group and the current frame edge image. We can complete image mosaic by them. We use video sequence which of the resolution is 1024 * 768 do the experiment. The results show that the method has good effect and strong adaptability. Algorithm is high efficiency which running time is 24 ms. It is suitable for real-time processing requirements of the application. This method is an effective mosaic technique which is suitable for engineering application. 2012 IEEE.  
Design of high speed and parallel compression system used in the big area CCD of high frame frequency (EI CONFERENCE) 会议论文  OAI收割
2011 International Conference on Precision Engineering and Non-Traditional Machining, PENTM 2011, December 9, 2011 - December 11, 2011, Xi'an, China
作者:  Li G.-N.;  Jin L.-X.;  Zhang R.-F.;  Wang W.-H.;  Li G.-N.
收藏  |  浏览/下载：51/0  |  提交时间：2013/03/25
According to the area CCD camera of characteristics  such as high resolution capacity and high frame frequency  this paper puts forward a high speed and parallel image compression system of high integration degree. Firstly  according to the work principle of the area CCD  FPGA is adopted to realize the timing driving and multichannel and parallel analog signal handling to raise the export frame frequency of the area CCD. Secondly  with an image compression scheme based on FPGA embedded processor MicroBlaze and ADV212 compression chip  real time image compression and the high speed area CCD are realized. Finally  by detecting the analog signal of the area CCD output  the real time compression of the big area CCD image is carried out in different compression ratios and the compression performance is analyzed. Experiment result shows that this scheme can realize real time image compression with the biggest data rate of 520Mbps. When compression bit ratio is 0.15  the signal-to-noise ratio of peak value can reach 36 dB. Image collection and image compression are integrated  which reduces the data transmission between them and improves systematic integration degree.  
Research of ballistic missile early warning system (EI CONFERENCE) 会议论文  OAI收割
2nd International Conference on Advanced Engineering Materials and Technology, AEMT 2012, July 6, 2012 - July 8, 2012, Zhuhai, China
Zhang M.-H.; Zhang Y.-Y.
收藏  |  浏览/下载：30/0  |  提交时间：2013/03/25
To develop a lift early warning infrared device  as a part of land or boat (ship) early warning system  the system has the ability to target pre-discovery and instructions invasion. Methods: In support of distant air situation  alerts the enemy aircraft  missiles and other long-range goals  obtain the target type and preliminary judgment of grade  deliver the alarm information to the command system. The infrared alarm device detects the target's own infrared radiation passively  alarms the incoming targets at low altitude and low altitude remote  when radar and other equipment is out of work. Results: The accuracy of entire system reached 20 according the analysis. Conclusions: The device has a full range of complex background  with high sensitivity  high resolution  anti-jamming  fast response time and other characteristics. (2012) Trans Tech Publications  Switzerland.  
Design of motion compensation mechanism of satellite remote sensing camera (EI CONFERENCE) 会议论文  OAI收割
International Symposium on Photoelectronic Detection and Imaging 2011: Space Exploration Technologies and Applications, May 24, 2011 - May 26, 2011, Beijing, China
Gu S.; Yan Y.; Xu K.; Jin G.
收藏  |  浏览/下载：47/0  |  提交时间：2013/03/25
With the development of aerospace remote sensing technology  the ground resolution of remote sensing camera enhances continuously. Since there is relative motion between camera and ground target when taking pictures  the target image recorded in recording media is moved and blurred. In order to enhance the imaging quality and resolution of the camera  the image motion had to be compensated. In order to abate the effect of image motion to image quality of space camera and improve the resolution of the camera  the compensation method of image motion to space camera is researched. First  the reason of producing drift angle and adjustment principle are analyzed in this paper. This paper introduce the composition and transmission principle of image motion compensation mechanism. Second  the system adopts 80C31 as controller of drift angle  and adopts stepping motor for actuators  and adopts absolute photoelectric encoder as the drift Angle measuring element. Then the control mathematical model of the image motion compensation mechanism are deduced  and it achieve the closed-loop control of the drift angle position. At the last  this paper analyses the transmission precision of the mechanism. Through the experiment  we measured the actual precision of the image motion compensation mechanism  and compared with the theoretical analysis. There are two major contributions in this paper. First  the traditional image motion compensation mechanism is big volume and quality heavy. This has not fit for the development trend of space camera miniaturization and lightweight. But if reduce the volume and quality of mechanism  it will bring adverse effects for the precision and stiffness of mechanism. For this problem  This paper designed a image motion compensation that have some advantages such as small size  light weight at the same time  high precision  stiffness and so on. This image motion compensation can be applicable to the small optics cameras with high resolution. Second  the traditional mechanism control need to corrected  fitting and iterative for the control formula of mechanism. Only in this way  we can get the optimal control mathematical model. This paper has high precision of the control formula derived. It can achieve the high precision control without fitting  It also simplify the difficulty of control mathematical model establishment. This paper designed the range of adjusting of image motion compensation mechanism between -5 +5. Based on choosing-5  -4  -3  -2  -1  0  +1  +2  +3  +4  +4 as the expectation value of the imaginary drift angle  we get ten groups of the fact data in adjusting drift angle measured. The test results show that the precision of the drift angle control system can be achieved in 1. It can meet the system requirements that the precision of the control system is less than 3'  and it can achieve the high-precision image motion compensation. 2011 SPIE.  
Multi-focus image fusion algorithm based on adaptive PCNN and wavelet transform (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
Wu Z.-G.; Wang M.-J.; Han G.-L.
收藏  |  浏览/下载：65/0  |  提交时间：2013/03/25
Being an efficient method of information fusion  image fusion has been used in many fields such as machine vision  medical diagnosis  military applications and remote sensing.In this paper  Pulse Coupled Neural Network (PCNN) is introduced in this research field for its interesting properties in image processing  including segmentation  target recognition et al.  and a novel algorithm based on PCNN and Wavelet Transform for Multi-focus image fusion is proposed. First  the two original images are decomposed by wavelet transform. Then  based on the PCNN  a fusion rule in the Wavelet domain is given. This algorithm uses the wavelet coefficient in each frequency domain as the linking strength  so that its value can be chosen adaptively. Wavelet coefficients map to the range of image gray-scale. The output threshold function attenuates to minimum gray over time. Then all pixels of image get the ignition. So  the output of PCNN in each iteration time is ignition wavelet coefficients of threshold strength in different time. At this moment  the sequences of ignition of wavelet coefficients represent ignition timing of each neuron. The ignition timing of PCNN in each neuron is mapped to corresponding image gray-scale range  which is a picture of ignition timing mapping. Then it can judge the targets in the neuron are obvious features or not obvious. The fusion coefficients are decided by the compare-selection operator with the firing time gradient maps and the fusion image is reconstructed by wavelet inverse transform. Furthermore  by this algorithm  the threshold adjusting constant is estimated by appointed iteration number. Furthermore  In order to sufficient reflect order of the firing time  the threshold adjusting constant is estimated by appointed iteration number. So after the iteration achieved  each of the wavelet coefficient is activated. In order to verify the effectiveness of proposed rules  the experiments upon Multi-focus image are done. Moreover  comparative results of evaluating fusion quality are listed. The experimental results show that the method can effectively enhance the edge details and improve the spatial resolution of the image. 2011 SPIE.  
DVI interface, optical fiber video transceiver used in LED display system (EI CONFERENCE) 会议论文  OAI收割
2011 IEEE 3rd International Conference on Communication Software and Networks, ICCSN 2011, May 27, 2011 - May 29, 2011, Xi'an, China
作者:  Wang R.;  Li S.
收藏  |  浏览/下载：24/0  |  提交时间：2013/03/25
A professional DVI-Video optical fiber transceiver was designed based on FPGA (Field Programmable Gate Array) in order to meet the need of real-time LED display. The system could be used to transmit a non-loss  real-time video source whose resolution was 1024 768 and refresh rate was 60Hz in a single mode optical fiber. The top-down design method was used while programming FPGA. Some module design ideas were discussed including video data acquisition  caching  framing  frame detecting and video reproducing. The required bandwidth of each module was analyzed and calculated in details. Some relevant simulation results were also given. In practical test  real-time video display was achieved. And the transmission rate of coded data was up to 2Gbps  and the transmission distance could reach 10km. 2011 IEEE.  
Astronomical image restoration through atmosphere turbulence by lucky imaging (EI CONFERENCE) 会议论文  OAI收割
3rd International Conference on Digital Image Processing, ICDIP 2011, April 15, 2011 - April 17, 2011, Chengdu, China
作者:  Zhao J.;  Wang J.;  Zhang S.
收藏  |  浏览/下载：26/0  |  提交时间：2013/03/25
In this paper  we develop a lucky imaging system to restore astronomical images through atmosphere turbulence. Our system takes very short exposures  on the order of the atmospheric coherence time. The rapidly changing turbulence leads to a very variable point spread function (PSF)  and the variability of the PSF leads to some frames having better quality than the rest. Only the best frames are selected  aligned and co-added to give a final image with much improved angular resolution. Our system mainly consists of five parts: preprocessing  frame selection  image registration  image reconstruction  and image enhancement. Our lucky imaging system has been successfully applied to restore the astronomical images taken by a 1.23m telescope. We have got clear images of moon surface and Jupiter  and our system can be demonstrated to greatly improve the imaging resolution through atmospheric turbulence. 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).  
Simulation and experiment of the static FTIR based on micro multi-step mirrors (EI CONFERENCE) 会议论文  OAI收割
International Symposium on Photoelectronic Detection and Imaging 2011: Sensor and Micromachined Optical Device Technologies, May 24, 2011 - May 26, 2011, Beijing, China
作者:  Liang Z.-Z.;  Zhang J.;  Zhang J.;  Zhang J.;  Zhu W.-B.
收藏  |  浏览/下载：29/0  |  提交时间：2013/03/25
In recent years  Fourier transform spectrometer (FTS) with small size and low mass is required in many applications with growing need for real-time and small platform spectral detection. In this paper  a micro Fourier transform infrared spectrometer (FTIR) based on spatial modulation mode was designed. This spectrometer has the advantages of high stability and simplified configuration. It also promises optical path differences (OPD) with high precision  as MOEMS technology is used in manufacturing the key components. The simulation and the experiments with regard to this FTIR configuration have been done. Firstly  the diffraction effect of the micro multi-step mirrors (MMSMs) is studied. We discuss the influence to the reversed spectrum by different mirror widths and different diffraction distances. Secondly  we simulate and analyze the influence of the source solid angle to the spectral resolution. Thirdly  we set up the theoretical model of the collimation error which is mainly from the defocus of the optical system and analyze the result caused by the collimation error. Fourthly  a new discrete Fourier transform arithmetic using least-squares cosines progression (LSCP) is proposed which can reconstruct the spectrum with nonuniform sampled signals. Finally  the MMSMs are fabricated used the MOEMS technology and the structural parameters are tested. 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).  
Study on supper resolution reconstruction based on staggered arrays (EI CONFERENCE) 会议论文  OAI收割
2011 International Conference on Electronic and Mechanical Engineering and Information Technology, EMEIT 2011, August 12, 2011 - August 14, 2011, Harbin, China
Yuan Z.; Xing Z.; Guang J.
收藏  |  浏览/下载：21/0  |  提交时间：2013/03/25
The image resolution can be improved without increasing the requirement to optical imaging systems' parameters and decreasing the size of CCD pixel by staggered arrays technology  which arranges several CCDs in a specific mode. In this paper  an image super resolution method of improving the image resolution for 1.5 times both in two directions by 4 linear arrays staggered based on this technology is presented  which avoids the large computation in a single time by use of circulation method. This method is proved effective by the digital simulation  and a simulated experiment platform is constructed to test its feasibility. The image resolution is improved for 1.42 times of the unreconstructed image according to the imaging experiment of resolution chart  which is closed to 1.5 times in ideal case. And also  the reconstructed and unreconstructed images are evaluated by the image information entropy  which proves that the reconstructed image contains more information. 2011 IEEE.