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	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.
	Image deformation based on contour using moving integral least squares 期刊论文 OAI收割 IET IMAGE PROCESSING, 2019, 卷号: 13, 期号: 1, 页码: 152-160 作者: Yu, Chong; Chen, Xi; Yin, Lei; Shu, Chang; Zhao, Li \| 收藏 \| 浏览/下载：87/0 \| 提交时间：2019/07/12 deformation least squares approximations optimisation image registration splines (mathematics) computational geometry feature extraction medical image processing deformation function effective image deformation methods contour image deformation method Integral Least Squares optimisation control contours desired contours intuitive deformations
	Discriminative Spatiotemporal Local Binary Pattern with Revisited Integral Projection for Spontaneous Facial Micro-Expression Recognition 期刊论文 OAI收割 IEEE TRANSACTIONS ON AFFECTIVE COMPUTING, 2019, 卷号: 10, 期号: 1, 页码: 32-47 作者: Huang, Xiaohua; Wang, Su-Jing; Liu, Xin; Zhao, Guoying; Feng, Xiaoyi \| 收藏 \| 浏览/下载：91/0 \| 提交时间：2019/04/22 Spontaneous facial micro-expression spatiotemporal local binary pattern integral projection feature selection
	Retaining Bindings of Integral Features in Working Memory: The Role of Object-based Attention 会议论文 OAI收割曲阜, 2017.7.1 作者: Xueyi Wan; Ying Zhou; Fan Wu; Mowei Shen; Zaifeng Gao \| 收藏 \| 浏览/下载：28/0 \| 提交时间：2017/12/28 feature binding integral feature object-based attention working memory
	Real-time pedestrian detection with the videos of car camera 期刊论文 OAI收割 ADVANCES IN MECHANICAL ENGINEERING, 2015, 卷号: 7, 期号: 12, 页码: 14731-14756 作者: Zhang, Yunling; Wang, Guofeng; Gu, Xingfa; Zhang, Shaoming; Hu, Jianping 收藏 \| 浏览/下载：62/0 \| 提交时间：2016/04/20 Pedestrian detection car camera integral channel feature graphics processing unit
	Object detection by spectropolarimeteric imagery fusion 会议论文 OAI收割 Institute of Electrical and Electronics Engineers Inc., 445 Hoes Lane / P.O. Box 1331, Piscataway, NJ 08855-1331, United States Zhao, Yong-Qiang; Gong, Peng; Pan, Quan 收藏 \| 浏览/下载：30/0 \| 提交时间：2014/12/07 Polarimeters Alarm systems Data fusion Electric fields Electromagnetism Feature extraction Fusion reactions Image sensors Integral equations Light measurement Magnetic materials Polarographic analysis Query processing Signal detection
	Slicing Recognition of Aircraft Integral Panel Generalized Pocket 期刊论文 OAI收割 CHINESE JOURNAL OF AERONAUTICS, 2008, 卷号: 21, 期号: 6, 页码: 585-592 作者: Yu Fangfang; Du Baorui; Ren Wenjie; Zheng Guolei; Chu Hongzhen \| 收藏 \| 浏览/下载：20/0 \| 提交时间：2021/02/02 SOLID MODELS FEATURES EXTRACTION numerical control aircraft integral panel feature extraction computer aided manufacturing
	Hierarchy structure characteristics analysis for the China Loess watersheds based on gully node calibration 期刊论文 OAI收割 JOURNAL OF MOUNTAIN SCIENCE, 卷号: 15, 期号: 12, 页码: 2637-2650 作者: Zhu, Hong-chun; Zhao, Yi-peng; Xu, Yue-xue; Liu, Hai-ying \| 收藏 \| 浏览/下载：22/0 \| 提交时间：2020/10/27 Digital elevation models Flow accumulation Gully structure feature point Hypsometric integral Loess landform Node calibration