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	Infrared dim target detecting algorithm based on multi-feature and spatio-temporal fusion 会议论文 OAI收割 Shanghai, China, 2021-10-28 作者: Bai, Mei; Zhang, Jian; Zhao, Hui \| 收藏 \| 浏览/下载：43/0 \| 提交时间：2022/03/18 Infrared Dim Target Detection TOP-HAT Improved-PM Multi-feature Fusion SCR
	An underlying clock in the extreme flip-flop state transitions of the black hole transient Swift J1658.2-4242 期刊论文 OAI收割 Astronomy and Astrophysics, 2020, 卷号: 641, 页码: A101 作者: HXMT \| 收藏 \| 浏览/下载：58/0 \| 提交时间：2022/02/08 accretion accretion disks black hole physics X-rays: binaries time Astrophysics - High Energy Astrophysical Phenomena Abstract: Aims: Flip-flops are top-hat-like X-ray flux variations, which have been observed in some transient accreting black hole binary systems, and feature simultaneous changes in the spectral hardness and the power density spectrum (PDS). They occur at a crucial time in the evolution of these systems, when the accretion disc emission starts to dominate over coronal emission. Flip-flops remain a poorly understood phenomenon, so we aim to thoroughly investigate them in a system featuring several such transitions. Methods: Within the multitude of observations of Swift J1658.2-4242 during its outburst in early 2018, we detected 15 flip-flops, enabling a detailed analysis of their individual properties and the differences between them. We present observations by XMM-Newton, NuSTAR, Astrosat, Swift, Insight-HXMT, INTEGRAL, and ATCA. We analysed their light curves, searched for periodicities, computed their PDSs, and fitted their X-ray spectra, to investigate the source behaviour during flip-flop transitions and how the interval featuring flip-flops differs from the rest of the outburst. Results: The flip-flops of Swift J1658.2-4242 are of an extreme variety, exhibiting flux differences of up to 77% within 100 s, which is much larger than what has been seen previously. We observed radical changes in the PDS simultaneous with the sharp flux variations, featuring transitions between the quasi-periodic oscillation types C and A, which have never been observed before. Changes in the PDS are delayed, but more rapid than changes in the light curve. Flip-flops occur in two intervals within the outburst, separated by about two weeks in which these phenomena were not seen. Transitions between the two flip-flop states occurred at random integer multiples of a fundamental period of 2.761 ks in the first interval and 2.61 ks in the second. Spectral analysis reveals the high and low flux flip-flop states to be very similar, but distinct from intervals lacking flip-flops. A change of the inner temperature of the accretion disc is responsible for most of the flux difference in the flip-flops. We also highlight the importance of correcting for the influence of the dust scattering halo on the X-ray spectra.
	An Omnidirectional Morphological Method for Aerial Point Target Detection Based on Infrared Dual-Band Model 期刊论文 OAI收割 Remote Sensing, 2018, 卷号: 10, 期号: 7, 页码: 26 作者: Liu, R.; Wang, D. J.; Jia, P.; Sun, H. \| 收藏 \| 浏览/下载：20/0 \| 提交时间：2019/09/17 point target detection dual-band model optimal fused probability of detection omnidirectional morphological filtering local difference criterion top-hat transform 2d images algorithm enhancement features filter track Remote Sensing
	An Iterative Black Top Hat Transform Algorithm for the Volume Estimation of Lunar Impact Craters 期刊论文 OAI收割 REMOTE SENSING, 2017, 卷号: 9, 期号: 9, 页码: 10 作者: Wang, Jiao; Cheng, Weiming; Luo, Wei; Zheng, Xinqi; Zhou, Chenghu \| 收藏 \| 浏览/下载：28/0 \| 提交时间：2019/09/25 Iterative Black Top Hat Transform (IBTH) crater volume Moon DEM
	The rational synthesis of (10,3)-type MOFs based on tetranuclear W(Mo)OS(3)Cu(3) (+) secondary building units 期刊论文 OAI收割 Chemical Communications, 2011, 卷号: 47, 期号: 36, 页码: 10049-10051 X. Q. Yao; Z. R. Pan; J. S. Hu; Y. Z. Li; Z. J. Guo; H. G. Zheng 收藏 \| 浏览/下载：46/0 \| 提交时间：2012/06/06 nonlinear-optical properties top-hat beams coordination polymers clusters ligands construction complexes networks blocks solids
	基于Top-Hat变换的高光谱吸收特征增强方法期刊论文 OAI收割光谱学与光谱分析, 2010, 页码: 2433-2437 李慧; 蔺启忠; 王钦军; 刘庆杰; 陈玉收藏 \| 浏览/下载：21/0 \| 提交时间：2015/01/04 高光谱特征增强多尺度Top-Hat变换反射光谱吸收峰增强 K-means聚类
	The Small Infrared Target Detection in Complicated Background Based on Adaptive Morphological Filter 会议论文 OAI收割 international congress on multispectral image processing and pattern recognition, 华中科技大学, 2009-10 作者: Li Z(李哲) 收藏 \| 浏览/下载：88/1 \| 提交时间：2010/01/19 Target detection complicated background small infrared target Top-Hat operator gray stretching
	Theory of surface thermal lens signal in optical coating with cw modulated top-hat beam excitation 期刊论文 OAI收割 ACTA PHYSICA SINICA, 2006, 卷号: 55, 期号: 9, 页码: 4673-4678 作者: Chen Xiao-Xiao; Li Bin-Cheng; Yang Ya-Pei 收藏 \| 浏览/下载：21/0 \| 提交时间：2015/09/21 surface thermal lens optical coating top-hat beam
	Nonlinear absorption measurement of UV dielectric components by pulsed top-hat beam thermal lens 期刊论文 OAI收割 OPTICS COMMUNICATIONS, 2005, 卷号: 244, 期号: 1-6, 页码: 367-376 作者: Li, BC; Xiong, SM; Zhang, YD; Martin, S; Welsch, E 收藏 \| 浏览/下载：14/0 \| 提交时间：2015/09/21 nonlinear absorption coefficient surface thermal lens top-hat beam excitation LaF3/MgF2 multilayers MgF2