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	Comparison of simulated backgrounds with in-orbit observations for HE, ME, and LE onboard Insight-HXMT 期刊论文 OAI收割 Astrophysics and Space Science, 2020, 卷号: 365, 页码: 158 作者: HXMT \| 收藏 \| 浏览/下载：51/0 \| 提交时间：2022/02/08 Insight-HXMT Geant4 simulation Background observation Astrophysics - Instrumentation and Methods for Astrophysics Abstract: Insight-HXMT, the first X-ray astronomical satellite in China, aims to reveal new sources in the Galaxy and to study fundamental physics of X-ray binaries from 1 to 250 keV. It has three collimated telescopes, the High Energy X-ray telescope (HE), the Medium Energy X-ray telescope (ME), and the Low Energy X-ray telescope (LE). Before the launch, in-orbit backgrounds of these three telescopes had been estimated through Geant4 simulation, in order to investigate the instrument performance and the achievement of scientific goals. In this work, these simulated backgrounds are compared with in-orbit observations. Good agreements are shown for all three telescopes. For HE, (1) the deviation of the simulated background rate after two years of operation in space is 5 % from the observation (2) the total background spectrum and the relative abundance of the 67 keV line show long-term increases both in simulations and observations. For ME, (1) the deviation of simulated background rate is within 15 % from the observation, and (2) there are no obvious long-term increase features in the background spectra of simulations and observations. For LE, the background level given by simulations is also consistent with observations. The consistencies of these comparisons validate that the Insight-HXMT mass model, i.e., space environment components and models adopted, physics processes selected, and detector constructions built, is reasonable. However, the line features at 7.5 and 8.0 keV, which are obvious in the observed spectra of LE, are not evident in simulations. This might result from uncertainties in the LE constructions.
	An adaptive edge detection method based on Canny operator (EI CONFERENCE) 会议论文 OAI收割 2011 International Conference on Civil Engineering and Building Materials, CEBM 2011, July 29, 2011 - July 31, 2011, Kunming, China 作者: Chen Y. 收藏 \| 浏览/下载：41/0 \| 提交时间：2013/03/25 This paper proposes an adaptive Canny operator edge detection algorithm. The proposed method can automatically set the threshold value according to the different image gray-scale gradient histogram adaptively and improve the performance in the detail edge detection and good localization. Experiments show that this method produces better edge detection results performance than the Otsu method. Besides our method Roberts operator Prewitt operator Sobel operator Log operator and Canny operator based on Otsu algorithm are also tested for comparisons. (2011) Trans Tech Publications Switzerland.
	Neural networks in finance and economics forecasting 期刊论文 OAI收割 INTERNATIONAL JOURNAL OF INFORMATION TECHNOLOGY & DECISION MAKING, 2007, 卷号: 6, 期号: 1, 页码: 113-140 作者: Huang, Wei; Lai, Kin Keung; Nakamori, Yoshiteru; Wang, Shouyang; Yu, Lean \| 收藏 \| 浏览/下载：22/0 \| 提交时间：2018/07/30 artificial neural networks finance forecasting economic forecasting input variables selection performance comparisons
	Super-resolved imaging system with oversampling technology (EI CONFERENCE) 会议论文 OAI收割 3rd International Symposium on Advanced Optical Manufacturing and Testing Technologies, AOMATT 2007: Advanced Optical Manufacturing Technologies, July 8, 2007 - July 12, 2007, Chengdu, China 作者: Zhang X.; Wang L.-J.; Wang L.-J.; Zhang J.-P.; Liu Y. 收藏 \| 浏览/下载：64/0 \| 提交时间：2013/03/25 It has been a significant issue in the imaging filed to provide the highest possible resolution of an electro-optical imaging system(E-O imaging system). CCD arrays are inherently undersampled and spatial frequency above Nyquist frequency is distorted so as to create ambiguity and Moire patterns for targets imaged by E-O system.. As to this drawback a system-design project is introduced and discussed in the paper. It's well known that many image quality metrics are linked to MTF. However CCDs don't satisfy MTF condition namely the shift-invariant property so MTF synthesis can't appraise the whole system simply by the MTF product of the few sub-system ones in E-O imaging system. Then it is depicted how to solve this problem in the following. Finally the analyses and comparisons of the imaging performance parameters with and without super-resolved technologies are shown.