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Anomalous Broadband Spectrum Photodetection in 2D Rhenium Disulfide Transistor 期刊论文
Advanced Optical Materials, 2019, 卷号: 7, 期号: 23, 页码: 9
作者:  D.Xiang;  T.Liu;  J.Y.Wang;  P.Wang;  L.Wang
收藏  |  浏览/下载：0/0  |  提交时间：2020/08/24
Development of cold optical infrared imaging terminal with multiband 期刊论文
Hongwai yu Jiguang Gongcheng/Infrared and Laser Engineering, 2018, 卷号: 47, 期号: 9
作者:  Huang, Zhiguo;  Wang, Jianli;  Yin, Limei;  Li, Hongzhuang;  Liu, Junchi
收藏  |  浏览/下载：8/0  |  提交时间：2019/09/17
The application of adaptive enhancement algorithm based on gray entropy in mammary gland CR image (EI CONFERENCE) 会议论文
2012 2nd International Conference on Consumer Electronics, Communications and Networks, CECNet 2012, April 21, 2012 - April 23, 2012, Three Gorges, China
Zhang M.-H.; Zhang Y.-Y.
收藏  |  浏览/下载：26/0  |  提交时间：2013/03/25
Mammary gland is composed entirely of soft tissue with approximate density  therefore mammary gland CR medicine radiation image presents a low contrast  and slight difference changes may be a manifestation of tumor  so it is necessary to enhance mammary gland CR image to improve its visual quality in order to meet the demands of doctor's clinical diagnosis. However the general enhancement algorithms over enhance the contrast and noise  due to image details lost  aiming at the defects  a mammary gland CR medicine image adaptive enhancement arithmetic based on image gray entropy is put forward. The arithmetic adapts dizzy image to magnify selected spatial frequency response in order to enhance the edge details of mammary gland CR images. It can adjust weighted factor K according to image gray characteristics namely pixel gray entropy. Experiments results demonstrate that mammary gland CR image enhanced by the algorithm has abundant details and high signal-to-noise ratio  moreover  CR image enhanced has good visual effect. So the method is effective and fit for enhancing CR medical radiation image edge details. 2012 IEEE.  
Improved TOPS about direction of arrival estimation for wideband signals (EI CONFERENCE) 会议论文
2011 International Conference on Vibration, Structural Engineering and Measurement, ICVSEM2011, October 21, 2011 - October 23, 2011, Shanghai, China
He B.
收藏  |  浏览/下载：13/0  |  提交时间：2013/03/25
The study about the direction-of-arrival (DOA) estimation for wideband signals is a basic topic of Signal Processing. The method called test of orthogonality of projected subspaces (TOPS) does not require initial values to form focusing matrix compared with the coherent signal subspace method (CSSM)  but it has poor performance for coherent wideband signals at low signal-to-noise ratio (SNR). Based on the lack of the conventional TOPS  this paper reconstructs a set of new matrices with the narrowband correlated matrices coming from the DFT decomposition of the array output and modifies the method frame of the conventional TOPS. So we get a set of reconstructed matrices with full rank corresponding to each frequency bin  and which have no array aperture loss. The improved TOPS can estimate the DOA for coherent wideband sources at low SNR  and enhances the performance of the conventional TOPS. Simulation results show that the improved TOPS is effective  and the total performance of which is similar to the rotational signal-subspace (RSS) method. (2012) Trans Tech Publications.  
The application of Kalman filtering technique on the multi-position strap-down north seeking system (EI CONFERENCE) 会议论文
2012 5th International Symposium on Computational Intelligence and Design, ISCID 2012, October 28, 2012 - October 29, 2012, Hangzhou, China
Shen C.-W.; Liu C.; Liu S.-J.; Cai S.
收藏  |  浏览/下载：19/0  |  提交时间：2013/03/25
The research of digltal CR medicine image adapitive enhancement method (EI CONFERENCE) 会议论文
4th International Conference on Mechanical and Electrical Technology, ICMET 2012, July 24, 2012 - July 26, 2012, Kuala Lumpur, Malaysia
Ming-Hui Z.; Yao-Yu Z.
收藏  |  浏览/下载：52/0  |  提交时间：2013/03/25
Digital CR medicine radiation image is in doctor's favor and has became medicine imaging technology new hot spot because of its high gray contrast  powerful computer disposal function  little radiation dosage  non-film diagnosis  different area consultation. But degradation of digital X-ray medical image such as low contrast and blurring during radiographic imaging  caused by complexity of body tissue and effects of X-ray scattering and electrical noise etc.  can worsen the results of analysis and diagnosis. So it is usually needed that CR medicine image is enhanced to improve its vision quality  and easy to doctor's more accurate diagnosis. The general enhancement algorithms over enhancing the contrast and lose image details  aiming at the defects  an enhancement algorithm for CR image is proposed based on the ratio of deviation to mean of domain. The arithmetic enhance CR image edge details by adjusting factor K based on the ratio of deviation to mean of domain of CR image. Experiment results demonstrate that the algorithm enhances CR image detail and CR image enhanced has good visual effect  the adaptive enhancement method is fit for CR medicine image. (2012) Trans Tech Publications  Switzerland.  
A hybrid median filter for enhancing dim small point targets and its fast implementation (EI CONFERENCE) 会议论文
2011 International Conference on Multimedia and Signal Processing, CMSP 2011, May 14, 2011 - May 15, 2011, Guilin, Guangxi, China
Yang Q.
收藏  |  浏览/下载：17/0  |  提交时间：2013/03/25
Weak stars and middle altitude orbit satellites or high altitude orbit satellites are presented as dim point targets in images of astronomical observation. They have low intensity and occupy few pixels in image. In most situations  the background of sky is always ununiform and there exists pulse noises. Thus results in targets submerging in background noises and low signal noise ratio (SNR). Median filter is an effective method for removing pulse noise. But it can blur image after modifying gray of non-noise pixels when image has low SNR. A hybrid median filter algorithm is proposed to process low SNR dim point targets image. The newly proposed method can suppress the pulse noises  also can increase target $SNR$ and does not add extra fake targets. The time complexity of median filter is O(N2)(N is the widow size) and is difficult to implement in hardware. For quasi real time application  a fast implementation of our hybrid median filter is proposed to reduce the time complexity to O(N). Experimental results show that the newly proposed algorithm is superior to ordinary median filter and fast median filter by comparing visual effect and performance. 2011 IEEE.  
Stabilization and tracking precision improved based on disturbance observer (EI CONFERENCE) 会议论文
2011 2nd International Conference on Mechanic Automation and Control Engineering, MACE 2011, July 15, 2011 - July 17, 2011, Inner Mongolia, China
Sun G.; Zhu M.; Jia H.
收藏  |  浏览/下载：19/0  |  提交时间：2013/03/25
Based on the kinematics of semi-strapdown seeker  the framework coordinate of the semi-strapdown seeker is established and the optical axis stabilization equation of semistrapdown seeker is deduced based on product of exponential (POE) formula. The stabilization control principle block diagram of semi-strapdown seeker is shown based on the stabilization equation. The main influence factors of the stability precision are pointed out  such as friction disturbance  velocity measurement noise and missile disturbance. For the sake of improving the stabilization precision and tracking precision  disturbance observer was proposed in the inner loop of semi-strapdown seeker servo-control system. The low frequency external disturbance and high frequency velocity measurement noise are effectively restrained by the disturbance observer as shown in hardware-in-loop simulation  and optical axis stabilization precision and tracking precision are greatly improved. 2011 IEEE.  
Research on infrared dim-point target detection and tracking under sea-sky-line complex background (EI CONFERENCE) 会议论文
International Symposium on Photoelectronic Detection and Imaging 2011: Advances in Infrared Imaging and Applications, May 24, 2011 - May 24, 2011, Beijing, China
Dong Y.-X.; Li Y.; Zhang H.-B.
收藏  |  浏览/下载：97/0  |  提交时间：2013/03/25
Target detection and tracking technology in infrared image is an important part of modern military defense system. Infrared dim-point targets detection and recognition under complex background is a difficulty and important strategic value and challenging research topic. The main objects that carrier-borne infrared vigilance system detected are sea-skimming aircrafts and missiles. Due to the characteristics of wide field of view of vigilance system  the target is usually under the sea clutter. Detection and recognition of the target will be taken great difficulties.There are some traditional point target detection algorithms  such as adaptive background prediction detecting method. When background has dispersion-decreasing structure  the traditional target detection algorithms would be more useful. But when the background has large gray gradient  such as sea-sky-line  sea waves etc.The bigger false-alarm rate will be taken in these local area.It could not obtain satisfactory results. Because dim-point target itself does not have obvious geometry or texture feature  in our opinion  from the perspective of mathematics  the detection of dim-point targets in image is about singular function analysis.And from the perspective image processing analysis  the judgment of isolated singularity in the image is key problem. The foregoing points for dim-point targets detection  its essence is a separation of target and background of different singularity characteristics.The image from infrared sensor usually accompanied by different kinds of noise. These external noises could be caused by the complicated background or from the sensor itself. The noise might affect target detection and tracking. Therefore  the purpose of the image preprocessing is to reduce the effects from noise  also to raise the SNR of image  and to increase the contrast of target and background. According to the low sea-skimming infrared flying small target characteristics  the median filter is used to eliminate noise  improve signal-to-noise ratio  then the multi-point multi-storey vertical Sobel algorithm will be used to detect the sea-sky-line  so that we can segment sea and sky in the image. Finally using centroid tracking method to capture and trace target. This method has been successfully used to trace target under the sea-sky complex background. 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).  
Optical axis stabilization of semi-strapdown seeker based on disturbance observer (EI CONFERENCE) 会议论文
2011 International Conference on Information and Automation, ICIA 2011, June 6, 2011 - June 8, 2011, Shenzhen, China
Sun G.; Zhu M.; Yin S.; Jia H.
收藏  |  浏览/下载：18/0  |  提交时间：2013/03/25
Based on the kinematics of semi-strapdown seeker  the framework coordinate of the seeker is established. The optical axis stability equation of semi-strapdown seeker is deduced by using attitude transformation matrix. Then  the stability control principle block diagram of semi-strapdown seeker is shown based on the stability equation. The main factors that influence the stabilization precision are pointed out  such as friction disturbance  velocity-measuring noise and missile disturbance. In order to improve the stabilization precision  disturbance observer was proposed in semi-strapdown seeker stability control. The low frequency external disturbance and high frequency velocity measurement noise are effectively restrained by the disturbance observer as shown in hardware-in-loop simulation  and optical axis stabilization precision is improved nearly 20 times and 5 times due to two different frequencies with same amplitude. 2011 IEEE.  

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