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Timing analysis of Swift J1658.2-4242's outburst in 2018 with Insight-HXMT, NICER and AstroSat 期刊论文  OAI收割
Journal of High Energy Astrophysics, 2019, 卷号: 24, 页码: 30-40
作者:  
HXMT
  |  收藏  |  浏览/下载:61/0  |  提交时间:2022/02/08
Accretion  accretion disks  Black hole physics  X-rays: binaries:  Swift J1658.2-4242  Astrophysics - High Energy Astrophysical Phenomena  Abstract: We present the observational results from a detailed timing analysis of the black hole candidate Swift J1658.2-4242 during its 2018 outburst with the observations of Hard X-ray Modulation Telescope (Insight-HXMT), Neutron Star Interior Composition Explorer (NICER) and AstroSat in 0.1-250 keV. The evolution of intensity, hardness and integrated fractional root mean square (rms) observed by Insight-HXMT and NICER are presented in this paper. Type-C quasi-periodic oscillations (QPOs) observed by NICER (0.8-3.5 Hz) and Insight-HXMT (1-1.6 Hz) are also reported in this work. The features of the QPOs are analyzed with an energy range of 0.5-50 keV. The relations between QPO frequency and other characteristics such as intensity, hardness and QPO rms are carefully studied. The timing and spectral properties indicate that Swift J1658.2-4242 is a black hole binary system. Besides, the rms spectra of the source calculated from the simultaneous observation of Insight-HXMT, NICER and AstroSat support the Lense-Thirring origin of the QPOs. The relation between QPO phase lag and the centroid frequency of Swift J1658.2-4242 reveals a near zero constant when < 4Hz and a soft phase lag at 6.68 Hz. This independence follows the same trend as the high inclination galactic black hole binaries such as MAXI J1659-152.  
Development and integration of a 50 Hz pellet injection system for the Experimental Advanced Superconducting Tokamak (EAST) 期刊论文  OAI收割
FUSION ENGINEERING AND DESIGN, 2017, 卷号: 114, 期号: 无, 页码: 40-46
作者:  
Yao, Xingjia;  Chen, Yue;  Hu, Jiansheng;  Vinyar, Igor;  Lukin, Alexander
收藏  |  浏览/下载:28/0  |  提交时间:2018/05/02
CSNS束流损失监测系统前端模拟电路设计 期刊论文  OAI收割
原子能科学技术, 2013, 期号: 10, 页码: 1896-1900
作者:  
肖帅;  郭娴;  田建民;  曾磊;  徐韬光
收藏  |  浏览/下载:32/0  |  提交时间:2015/12/14
Comparison of experiment and simulation on dielectric barrier discharge driven by 50 hz ac power in atmospheric air 期刊论文  iSwitch采集
Journal of electrostatics, 2010, 卷号: 68, 期号: 5, 页码: 445-452
作者:  
Zhang, Cheng;  Shao, Tao;  Yu, Yang;  Niu, Zheng;  Yan, Ping
收藏  |  浏览/下载:34/0  |  提交时间:2019/05/10
Design of high-speed low-noise pre-amplifier for CCD camera (EI CONFERENCE) 会议论文  OAI收割
5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optoelectronic Materials and Devices for Detector, Imager, Display, and Energy Conversion Technology, April 26, 2010 - April 29, 2010, Dalian, China
作者:  
Zhang S.
收藏  |  浏览/下载:45/0  |  提交时间:2013/03/25
Pre-amplifier circuit is critical for the noise performance of the high speed CCD camera. Its main functions are amplification and impedance transform. The high speed and low noise pre-amplifier of CCD camera is discussed and designed in this paper. The high speed and low noise operational amplifier OPA842 is adopted as the main part. The gain-set resistors for the amplifier are designed optimally. The different precision gain-set resistors are swept using Monte Carlo method. CCD video signal which has high DC offset voltage is AC coupled to the amplifier. The output signal of the amplifier is source terminated using 50 ohms matching resistor so as to transmit the video signal through coaxial cable. When the circuit works in high speed  the PCB will have important effect to circuit performance and can even cause the amplifier unstable due to the parasitic problem of PCB. So the parasitic model of the PCB is established and the PCB layout design issues are also presented. The design result shows that the pre-amplifier can be used in the camera whose pixel rate could be up to 40 MHz and its input referred noise density is about 3 nV/Hz 1/2. 2010 Copyright SPIE - The International Society for Optical Engineering.  
Embedded system of time uniform based on DSP (EI CONFERENCE) 会议论文  OAI收割
2010 International Conference on Computer, Mechatronics, Control and Electronic Engineering, CMCE 2010, August 24, 2010 - August 26, 2010, Changchun, China
作者:  
Li N.;  Liu C.-X.;  Liu C.-X.;  Chen J.;  Guo L.-H.
收藏  |  浏览/下载:30/0  |  提交时间:2013/03/25
We introduced a design method of DSP-based System of time uniform  which combine the GPS and the Compass to calibrate the time. The system can use UTC (Coordinated Universal Time) of the GPS or the Compass for time base  to generate absolute time and different frequency of synchronous signals. We used DSP (Digital Signal Processor) to calculate the satellite information which includes the UTC time. After getting the UCT time information  put it into the CPLD (Complex Programmable Logic Device) for correction of time delay and serialization to output. Meanwhile  we divided 1PPS (one-pulse-per-second) signal of the GPS and the Compass into 20Hz  50Hz  and 800Hz synchronous signal. And we analyzed the precision of time and frequency. To conclude  the uncertainty of system absolute time is less than 100ns  the uncertainty of system synchronous signals is less than 20ns. This system is easy and flexible for use  stable and reliable in performance. 2010 IEEE.  
Space optics remote sensor focusing components mechanics characteristic analysis based on FEM (EI CONFERENCE) 会议论文  OAI收割
International Symposium on Photoelectronic Detection and Imaging 2009: Material and Device Technology for Sensors, June 17, 2009 - June 19, 2009, Beijing, China
作者:  
Wang B.;  Ren J.-Y.;  Wang B.
收藏  |  浏览/下载:167/0  |  提交时间:2013/03/25
Space optical remote sensor is very important in many fields of science and military significance. It is widely applied. Space optical remote sensor design and manufacturing require precision and stability. Focusing mechanics is an important component of remote sensors. Focusing mechanics can guarantee the stability of the entire mechanics focusing accuracy  therefore the stability of research focusing mechanics is very important. In order to guarantee the space optics remote sensor focusing mechanics the stability  takes steps the space optics remote sensor focusing organization mechanics characteristic analysis from the classics contact theory. This article uses international general non-linear finite element analysis software ABAQUS to carry on mechanics characteristic analysis to the space optics remote sensor focusing mechanics. First acts according to the focusing mechanics unique feature  carries on the finite element to the structural model the grid division  the material attribute disposition and the boundary condition indeed grades. Then establishment contact non-linear finite element model  and to focusing organization finite element model infliction unit action. Like this contacts the result and the equivalent static analysis result which the nonlinear analysis obtains carries on the contrast and the analysis. This article last count result modality is 90HZ  satisfies the space optics remote sensor structure overall modality to request to be bigger than 50HZ.This article when carries on the dynamic analysis  extracts the structure kinetic energy and the acceleration curve. In the dynamic analysis obtained transient response analysis modality 70.5Hz  this also is bigger than 50HZ. The dynamic analysis indicated the structure dynamic stability has the distinct enhancement  has provided certain foundation for the space optics remote sensor following development work  reduced the overall system development cycle. 2009 SPIE.  
V-shaped electro-optic characteristics in FLC gels (EI CONFERENCE) 会议论文  OAI收割
作者:  
Li J.;  Li J.;  Li J.;  Xuan L.
收藏  |  浏览/下载:36/0  |  提交时间:2013/03/25
The effects of polymer network formed under UV irradiation with electric field application ( 50V  5Hz) to ferroelectric liquid crystal (FLC) molecules orientation and electrooptic characteristics have been studied. The polymer network formed in SmC*phase is anisotropic and fibrils-like  and a typical striped texture was observed in the cell. The FLC gels exhibit a symmetric V-shaped electrooptic characteristics with thresholdless voltage and high contrast ratio (40:1). A theory explanation of the unique properties is given by establishing a molecular orientation model and conducting a computer simulation. A good fitting of the electrooptic dynamic response of FLC gels has been obtained by introducing a potential (bulk anchoring energy) originated from the photo-cured polymer network. 2002 Taylor Francis.