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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.
	Design of FOPI Controller for Time Delay Systems and Its Experimental Validation 期刊论文 OAI收割 International Journal of Automation and Computing, 2019, 卷号: 16, 期号: 3, 页码: 310-328 作者: Gargi Baruah; Somanath Majhi; Chitralekha Mahanta \| 收藏 \| 浏览/下载：28/0 \| 提交时间：2021/02/22 Auto-tuning fractional order proportional integral (FOPI) first order plus dead time (FOPDT) balanced tuning coupled tank system (CTS).
	Multi-channel high-speed TDICCD image data acquisition and storage system (EI CONFERENCE) 会议论文 OAI收割 2010 International Conference on E-Product E-Service and E-Entertainment, ICEEE2010, November 7, 2010 - November 9, 2010, Henan, China 作者: Li Y.; Li Y.; Li Y.; Li Y. 收藏 \| 浏览/下载：28/0 \| 提交时间：2013/03/25 For multi-channel high-speed image data of certain space remote sensing camera this paper proposed a new image data acquisition and storage system. First of all the system uses Field-Programmable Gate Array(FPGA) controlling synchronous dynamic random access memory(SDRAM) array to realize the cache of image data then according to the received commands sends certain channel's image data to the acquisition card to write the image data into SCSI hard disk and implements the final storage. A Time Delay Integral Charge Couple Device(TDICCD) image data acquisition and storage system with five channels is developed pixel clock rate is up to 96MHz total effective data rate is up to 2.88Gb/s single channel storage depth is up to 7810 lines. The experimental results indicate that this system work stably high effectively which can meet the requirement of acquisition and storage of multi-channel high-speed TDICCD image data. 2010 IEEE.
	Discrete variational principle and first integrals for Lagrange-Maxwell mechanico-electrical systems 期刊论文 OAI收割 CHINESE PHYSICS, 2007, 卷号: 16, 期号: 3, 页码: 570-577 作者: Fu Jing-Li; Dai Gui-Dong; Jimenez, Salvador; Tang Yi-Fa \| 收藏 \| 浏览/下载：16/0 \| 提交时间：2018/07/30 discrete variational principle first integral mechanico-electrical systems