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	Research on data processing method for detection of small and weak targets in space 会议论文 OAI收割 ELECTR NETWORK, 2022-11-24 作者: Sen, Tian; Yan, Wen \| 收藏 \| 浏览/下载：17/0 \| 提交时间：2023/06/19 the Milky Way's background low signal to noise ratio target detection multiframe superposition
	Controllable synthesized diamond/CNWs film as a novel nanocarbon electrode with wide potential window and enhanced S/B ratio for electrochemical sensing 期刊论文 OAI收割 APPLIED SURFACE SCIENCE, 2021, 卷号: 551, 页码: 9 作者: Zhou, Meiqi; Zhai, Zhaofeng; Liu, Lusheng; Zhang, Chuyan; Yuan, Ziyao \| 收藏 \| 浏览/下载：48/0 \| 提交时间：2021/10/15 Thin film Diamond/carbon nanowalls Potential window Signal to background ratio Electrochemical sensing
	Space Debris Detection Using Feature Learning of Candidate Regions in Optical Image Sequences 期刊论文 OAI收割 IEEE ACCESS, 2020, 卷号: 8, 页码: 150864-150877 作者: Xi, Jiangbo; Xiang, Yaobing; Ersoy, Okan K.; Cong, Ming; Wei, Xin \| 收藏 \| 浏览/下载：42/0 \| 提交时间：2020/10/23 Space debris Feature extraction Machine learning Signal to noise ratio Object detection Image sequences Optical imaging Space debris detection background estimation candidate region extraction deep learning
	Comparative Study on Laser Induced Breakdown Spectroscopy Based on Single Pulse and Re-Heating Orthogonal Dual Pulse 期刊论文 OAI收割 SPECTROSCOPY AND SPECTRAL ANALYSIS, 2017, 卷号: 37, 期号: 2, 页码: 588-593 作者: Yu Yang; Zhao Nan-jing; Fang Li; Meng De-shuo; Gu Yan-hong 收藏 \| 浏览/下载：19/0 \| 提交时间：2018/05/02 Laser-induced Breakdown Spectroscopy Orthogonal Dual-pulse Spectral Enhancement Signal-to-background Ratio Plasma Temperature Electron Density
	A hybrid median filter for enhancing dim small point targets and its fast implementation (EI CONFERENCE) 会议论文 OAI收割 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：22/0 \| 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.
	Evaluation of the operating range for ground-based infrared imaging tracking system (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: Zhang Z.-D. 收藏 \| 浏览/下载：49/0 \| 提交时间：2013/03/25 Ground-based infrared imaging tracking system (GIITS) is of great importance for aerial target warning and guard. The operating range is one of the key performance specifications on the other which should be calculated calculate the radiation power received on the detector in order to analysis whether the output signal meets the detection requirements or not analyzed and studied during the whole GIITS design process. The operating range is mostly influenced by a few factors without considering the effect of the background radiation. By improving of the traditional method including atmospheric attenuation a new operating range calculation model of the GIITS was established based on two requirements. One is that the image size of observed target should meet the requirement of the processor signal extraction. The number of the pixel occupied by target image should be more than 9. The other is that the signal noise ratio (SNR) of the GIITS should not be less than 5 to meet the requirements of the target detection probability and spatial frequency. The SNR calculation equation in form of energy is deduced and the radiation characteristic of the observed target and background are analyzed. When evaluate the operating range of the GIITS using the new method the performance of GIITS and feature of target and background. This paper firstly makes analysis and summarization on the definite localizations of the traditional operating range equation of the GIITS. The localizations are mainly in two aspects. On one hand we should successively calculate two operating range values according to two requirements mentioned above and choose the minimum value as the analytic result. In the end the dispersion of the image and the effect of image dispersion are not considered in the traditional method an evaluation of operating range for fighter aircraft is accomplished as an example. The influence factors in every aspect on operating range were explored by the calculated result. The new operating range calculation model provides the theoretical basis for the design and applications as well as the comprehensive evaluation of a GIITS. 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).
	Research on infrared dim-point target detection and tracking under sea-sky-line complex background (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: Dong Y.-X.; Zhang H.-B.; Li Y.; Li Y.; Li Y. 收藏 \| 浏览/下载：111/0 \| 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).
	A sensitive solid-phase time-resolved fluorescence immunoassay apparatus (EI CONFERENCE) 会议论文 OAI收割 International Symposium on Photoelectronic Detection and Imaging 2009: Laser Sensing and Imaging, June 17, 2009 - June 19, 2009, Beijing, China 作者: Song K.-F.; Li J.-L.; Zhang W.-L.; Wang Y.-L. 收藏 \| 浏览/下载：37/0 \| 提交时间：2013/03/25 In the device a He-Ne laser of flash frequency 1-20 Hz was adopted as exciting light source and three key technical problems have been solved successfully in order to enhance the detecting sensitivity and measuring stability of the device for time-resolved fluorimmunoassays(TRFIA) [1]. The first one is to design optimum exciting optical system so that the exciting light beam excite the sample most effectively. The second one is to have a project spectrum filter which can reduce the affection of the background light to the photomultiplier tube and also ensure influence of the stray light and mixed diffusion light to the sample fluorescence to the least the sample fluorescence through the integrating sphere and come to the grating monochromator The right wavelength will be chosed through changing the angle of incidence of the grating monochromator. The third one is to simulate the principle of sample averaging of BOXCAR averager. In the device SCM was used as primary controller and CPLD was used as timing controller. Through the preparation process signal-to-noise ratio(SNR) will be improved also adjust delay time ampling frequency and sampling number arbitrarily. By testing the sensitivity is 10-12mol/L(substance marked by Eu3+) examination repeat is &le2.5% examination linearity is from 10 -8mol/L to 10-12mol/L correlation coefficient is 99.98%(p&le0.01). The instrument is advanced for ultrasensitive detection of antigen and antibody and solve the tumor genetic variation the virus protein detection. 2009 SPIE.