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Impedance of Hot-Electron Bolometer Mixers at Terahertz Frequencies 期刊论文
IEEE TRANSACTIONS ON TERAHERTZ SCIENCE AND TECHNOLOGY, 2011, 卷号: 1, 期号: 2, 页码: 383-389
作者:  Kollberg, Erik L.;  Yngvesson, K. Sigfrid;  Ren, Yuan;  Zhang, Wen;  Khosropanah, Pourya
收藏  |  浏览/下载：25/0  |  提交时间：2012/08/07
An asic design for lhaaso 期刊论文
Science china-physics mechanics & astronomy, 2011, 卷号: 54, 期号: 10, 页码: 1911-1914
作者:  Yan XiongBo;  Wang Zheng;  Chang JinFan;  Wei Wei;  Lu WeiGuo
收藏  |  浏览/下载：24/0  |  提交时间：2019/04/23
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：98/0  |  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.  
A CMOS-MEMS Gyroscope Interface Circuit Design With High Gain and Low Temperature Dependence 期刊论文
ieee sensors journal, 2011
Sun, Hongzhi; Jia, Kemiao; Liu, Xuesong; Yan, Guizhen; Hsu, Yu-Wen; Fox, Robert M.; Xie, Huikai
收藏  |  浏览/下载：13/0  |  提交时间：2015/11/12
Programmable Readout Circuit for Capacitive Accelerometer 其他
2011-01-01
Huang Jingqing; Zhang Mingming; Chen Zhongjian; Hao Yilong; Li Haojiong; Meng Xiangyun; Lu Wengao; Zhang Yacong; Su Weiguo; Li Song
收藏  |  浏览/下载：15/0  |  提交时间：2015/11/16
Verilog-A Modeling and Design of a Micromachined Capacitive Accelerometer 其他
2011-01-01
Li Haojiong; Zhang Mingming; Chen Zhongjian; Huang Jingqing; Meng Xiangyun; Lu Wengao; Zhang Yacong; Su Weiguo; Li Song
收藏  |  浏览/下载：4/0  |  提交时间：2015/11/16
Techniques to improve the accuracy of noise power spectrum measurements in digital x‐ray imaging based on background trends removal 期刊论文
Medical Physics, 2011, 卷号: Vol.38 No.3, 页码: 1600-1610
作者:  Zhou, Z.a,b;  Gao, F.a,b;  Zhao, H.a,b;  Zhang, L.a,b
收藏  |  浏览/下载：1/0  |  提交时间：2019/11/26

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