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	Synchronous X-ray/Optical QPOs from the Black Hole LMXB MAXI J1820+070 期刊论文 OAI收割 Monthly Notices of the Royal Astronomical Society, 2021 作者: HXMT \| 收藏 \| 浏览/下载：59/0 \| 提交时间：2022/02/08 black hole physics Low Mass X-ray Binaries accretion accretion discs stars: individual (MAXI J1820+070) Astrophysics - High Energy Astrophysical Phenomena Abstract: We present high-speed optical photometry from SAAO and SALT on the black hole LMXB MAXI J1820+070 (ASSASN-18ey), some of it simultaneous with NICER, Swift and Insight-HXMT X-ray coverage. We detect optical Quasi-Periodic Oscillations (QPOs) that move to higher frequencies as the outburst progresses, tracking both the frequency and evolution of similar X-ray QPOs previously reported. Correlated X-ray/optical data reveal a complex pattern of lags, including an anti-correlation and a sub-second lag that evolve over the first few weeks of outburst. They also show correlated components separated by a lag equal to the QPO period roughly centered on zero lag, implying that the inter-band variability is strongly and consistently affected by these QPOs at a constant phase lag of roughly ±Ю The synchronisation of X-ray and optical QPOs indicates that they must be produced in regions physically very close to each other we thus propose that they can be explained by a precessing jet model, based on analogies with V404 Cyg and MAXI J1348-630.
	Development of a series of dummy loads in S-band 期刊论文 OAI收割 HIGH POWER LASER AND PARTICLE BEAMS, 2015, 卷号: 27, 期号: 6, 页码: 65105 作者: He X(贺祥); Zhao FL(赵风利); Wang XJ(王湘鉴); Zhang JR(张敬如); Shu G(束冠) 收藏 \| 浏览/下载：28/0 \| 提交时间：2016/04/18 Frequency band width High power High power performance Long-time operation Low-voltage standing wave ratios Pulse repetition frequencies Simulation and optimization Voltage standing-wave ratio
	Rapid Micro-Patterning of a Conductive PANI/MWNTs-Polymer Composite Using an Optically-induced Electrokinetics Chip 会议论文 OAI收割 IEEE Nanotechnology Materials and Devices Conference (IEEE NMDC), Honolulu, HI, OCT 16-19, 2012 作者: Liu N(刘娜); Liang WF(梁文峰); Mai, John D.; Dong ZL(董再励); Li WJ(李文荣) 收藏 \| 浏览/下载：38/0 \| 提交时间：2013/12/26 A flexible, dynamically programmable and low-cost method applicable to micro-patterning of a conductive polymer/carbon nanotube composite solution is significant due to the potential applications in many areas. This paper demonstrates a new micro-patterning method for fabricating electrodes from a conductive polyaniline (PANI)/MWNT composite using an optically-induced electrokinetics (OEK) chip. This method quickly patterns flexible polymeric electrodes with different geometries when a square waveform signal with amplitudes from 16-20 Volts and frequencies from 20-30 kHz are applied. The geometric dimensions of the electrodes can be varied dynamically by controlling the size and exposure time of the light pattern. The surface morphology of electrodes patterned by this method is scanned by an atomic force microscope (AFM) and a scanning electron microscope (SEM) which show that the electrodes are uniform and continuous. Furthermore, the geometric dimensions and resistances of the electrodes are measured and analyzed. Experimental results reveal that the relationship between the resistance and geometries of the electrodes obey Ohm's law and the resistivity of the electrodes is about 0.03 Omega.m.
	Optical axis stabilization of semi-strapdown seeker based on disturbance observer (EI CONFERENCE) 会议论文 OAI收割 2011 International Conference on Information and Automation, ICIA 2011, June 6, 2011 - June 8, 2011, Shenzhen, China Sun G.; Zhu M.; Yin S.; Jia H. 收藏 \| 浏览/下载：29/0 \| 提交时间：2013/03/25 Based on the kinematics of semi-strapdown seeker the framework coordinate of the seeker is established. The optical axis stability equation of semi-strapdown seeker is deduced by using attitude transformation matrix. Then the stability control principle block diagram of semi-strapdown seeker is shown based on the stability equation. The main factors that influence the stabilization precision are pointed out such as friction disturbance velocity-measuring noise and missile disturbance. In order to improve the stabilization precision disturbance observer was proposed in semi-strapdown seeker stability control. The low frequency external disturbance and high frequency velocity measurement noise are effectively restrained by the disturbance observer as shown in hardware-in-loop simulation and optical axis stabilization precision is improved nearly 20 times and 5 times due to two different frequencies with same amplitude. 2011 IEEE.
	Seismic wave propagation through surface basalts - implications for coal seismic surveys 期刊论文 OAI收割 EXPLORATION GEOPHYSICS, 2010, 卷号: 41, 期号: 1, 页码: 1-8 作者: Sun, Weijia; Zhou, Binzhong; Hatherly, Peter; Fu, Li-Yun \| 收藏 \| 浏览/下载：24/0 \| 提交时间：2018/09/26 Coal Seam Finite Difference Forward Modelling Inhomogeneity Long-offset Recording Low Frequencies Sub-basalt Imaging
	Seismic wave propagation through surface basalts - implications for coal seismic surveys 期刊论文 OAI收割 EXPLORATION GEOPHYSICS, 2010, 卷号: 41, 期号: 1, 页码: 1-8 作者: Sun, Weijia; Zhou, Binzhong; Hatherly, Peter; Fu, Li-Yun \| 收藏 \| 浏览/下载：23/0 \| 提交时间：2018/09/26 Coal Seam Finite Difference Forward Modelling Inhomogeneity Long-offset Recording Low Frequencies Sub-basalt Imaging
	Correction method for detection of the frequencies of railway fsk signals (EI CONFERENCE) 会议论文 OAI收割 2008 9th International Conference on Signal Processing, ICSP 2008, October 26, 2008 - October 29, 2008, Beijing, China 作者: Yu J. 收藏 \| 浏览/下载：68/0 \| 提交时间：2013/03/25 In order to acquire the information of railway binary frequency-shift keying signals which include upper/down side frequencies and base low-frequency with high-accuracy a novel frequency detection algorithm for France UM-71 system is proposed. Combining fast Fourier transform with the ratio correction method the carrier frequency and the base frequency are obtained. Furthermore the hardware consumption has been decreased. And it possesses the advantage of simple algorithm and fast operation speed. Comparing with the detection of the base frequency the upper/down side frequency of railway signal is more difficult. Based on spectrum analysis and the spectrum correction a new method which adopts the sliding window is put forward in this paper. The absolute differences between the upper side frequencies and the down side frequencies obtained are regarded as the criterion for judgment. Then the set of data in which the maximum absolute value is is to be the result of the upper/down side frequency. Because the sliding window will go through every stage when the upper/down side frequency changes therefore it is not sensitive enough to the position of data which need to be transformed. Using the method mentioned above the experiment results show that the accuracy requirement of the side frequency is satisfied well. 2008 IEEE.