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	Comparison of simulated backgrounds with in-orbit observations for HE, ME, and LE onboard Insight-HXMT 期刊论文 OAI收割 Astrophysics and Space Science, 2020, 卷号: 365, 页码: 158 作者: HXMT \| 收藏 \| 浏览/下载：50/0 \| 提交时间：2022/02/08 Insight-HXMT Geant4 simulation Background observation Astrophysics - Instrumentation and Methods for Astrophysics Abstract: Insight-HXMT, the first X-ray astronomical satellite in China, aims to reveal new sources in the Galaxy and to study fundamental physics of X-ray binaries from 1 to 250 keV. It has three collimated telescopes, the High Energy X-ray telescope (HE), the Medium Energy X-ray telescope (ME), and the Low Energy X-ray telescope (LE). Before the launch, in-orbit backgrounds of these three telescopes had been estimated through Geant4 simulation, in order to investigate the instrument performance and the achievement of scientific goals. In this work, these simulated backgrounds are compared with in-orbit observations. Good agreements are shown for all three telescopes. For HE, (1) the deviation of the simulated background rate after two years of operation in space is 5 % from the observation (2) the total background spectrum and the relative abundance of the 67 keV line show long-term increases both in simulations and observations. For ME, (1) the deviation of simulated background rate is within 15 % from the observation, and (2) there are no obvious long-term increase features in the background spectra of simulations and observations. For LE, the background level given by simulations is also consistent with observations. The consistencies of these comparisons validate that the Insight-HXMT mass model, i.e., space environment components and models adopted, physics processes selected, and detector constructions built, is reasonable. However, the line features at 7.5 and 8.0 keV, which are obvious in the observed spectra of LE, are not evident in simulations. This might result from uncertainties in the LE constructions.
	Multi-scale variability of the tropical Indian Ocean circulation system revealed by recent observations 期刊论文 OAI收割 SCIENCE CHINA-EARTH SCIENCES, 2018, 卷号: 61, 期号: 6, 页码: 668-680 作者: Wang, Weiqiang; Huang, Ke; Wang, Dongxiao; Chen, Gengxin(Chinese Acad Sci, Souh China Sea Inst Oceanol, State Key Lab Trop Oceanog, Guangzhou 510301, Guangdong, Peoples R China); Chen, Gengxin \| 收藏 \| 浏览/下载：71/0 \| 提交时间：2018/07/20 Equatorial Undercurrent Equatorial Intermediate Current Eastern Indian Ocean Upwelling Bay Of Bengal Circulation Multi-scale Variability Equatorial Wave Dynamics Observation And Simulation
	Multi-scale variability of the tropical Indian Ocean circulation system revealed by recent observations 期刊论文 OAI收割 SCIENCE CHINA-EARTH SCIENCES, 2018, 卷号: 61, 期号: 6, 页码: 668-680 作者: Huang, K; Wang, DX; Wang, WQ; Xie, Q; Chen, J \| 收藏 \| 浏览/下载：38/0 \| 提交时间：2018/09/03 Equatorial undercurrent Equatorial intermediate current Eastern Indian Ocean upwelling Bay of Bengal circulation Multi-scale variability Equatorial wave dynamics Observation and simulation
	Reliable attitude stability control of quad-rotor based on fault-tolerant approach (EI CONFERENCE) 会议论文 OAI收割 2012 9th IEEE International Conference on Mechatronics and Automation, ICMA 2012, August 5, 2012 - August 8, 2012, Chengdu, China 作者: Gao Q. 收藏 \| 浏览/下载：41/0 \| 提交时间：2013/03/25 The reliability flight property has received much attention within the aircraft control community throughout the last decades. In this paper the fault-tolerant control technique is introduced into the attitude stability control system of a quadrotor UAV in order to compensate the influence of the actuators fault of the aircraft. This control scheme is composed of two components: a robust fault detection module using the modelbased observation approach and a reconfigurable controller. Besides the designing procedure the theoretical analysis of robustness and stability of the designed FTC scheme are also contained in this article. And finally the availability of the proposed scheme is verified through numerical simulation. 2012 IEEE.
	Study of three-mode parametric instability (EI CONFERENCE) 会议论文 OAI收割 8th Edoardo Amaldi Conference on Gravitational Waves, June 21, 2009 - June 26, 2009, New York, NY, United states Liang F.; Zhao C.; Gras S.; Ju L.; Blair G. 收藏 \| 浏览/下载：21/0 \| 提交时间：2013/03/25 The effect of parametric instability in advanced interferometric gravitational wave detectors is a potential problem for their proper operation. Great efforts have been made to study the onset of parametric instabilities and to find ways to control them. Here we present an experimental design for studying parametric instability in a 72 m cavity with suspended high quality fused silica mirrors. With 5 W input power and 20 kW circulation power inside the cavity it is predicted that parametric instability will occur. The resonant condition of parametric instability can be met by thermally tuning the radius of curvature of a test mass. We will present simulation results of parametric gains for different radii of curvature of a test mass. The simulation results will provide the basis for designing the thermal tuning and observation parametric instability experiments. This will provide a test bed for studying parametric instability and its control for next generation detectors. 2010 IOP Publishing Ltd.
	Modeling of satellite borne TDI CCD pitching imaging image motion velocity vector (EI CONFERENCE) 会议论文 OAI收割 2009 IEEE International Conference on Automation and Logistics, ICAL 2009, August 5, 2009 - August 7, 2009, Shenyang, China 作者: Zhang L.; Li S.; Zhang L. 收藏 \| 浏览/下载：14/0 \| 提交时间：2013/03/25 In order to obtain three-dimensional observation effect with single satellite borne time delay and integrate charge coupled device (TDI-CCD) pitching imaging is required. More accurate real-time image motion velocity vector computational model of space camera is also necessary to make the imaging perfect. Imaging motion velocity vector computation model must be set up on image plane at pitching imaging. According to the geometric relationship between the pitching imaging space camera and the Earth's rotation motion satellite borne TDI CCD pitching imaging motion velocity vector model is derived by mapping the ground speed to the image plane and using coordinate transformation method. The numerical simulation results show that the image velocity model can reduce deviation angle error about 33' and about 30% image motion speed error compared to traditional ground velocity model. 2009 IEEE.
	Application of CMOS APS star tracker with large FOV in attitude and angular velocity determination (EI CONFERENCE) 会议论文 OAI收割 Advanced Sensor Systems and Applications III, November 12, 2007 - November 14, 2007, Beijing, China Lu D.; Guang J.; Shaoju W.; Tao C. 收藏 \| 浏览/下载：30/0 \| 提交时间：2013/03/25 The paper deals with the spacecraft attitude determination problem using a new kind of star tracker with large FOV based on CMOS APS. Star tracker has been developed since 1970s and proved to be the most accurate sensor ever used in the spacecraft attitude determination systems. But the traditional CCD star tracker also has some disadvantages such as small FOV high power consumption low sample rate and low working angular rate limit which prevent the use of CCD star tracker in attitude large angle maneuvering process. The new kind of star tracker based on CMOS APS has no such disadvantages and is more applicable on modern low-cost agile small satellites. Its higher sample rate and working angular rate limit over traditional CCD star tracker make it more adapt for spacecraft angular velocity determination. Because of the large FOV of the star tracker the mathematical model of traditional CCD star tracker with a small FOV is not appropriate. So a new mathematical model was quoted to fit the star tracker with a large FOV. An alternative adaptive algorithm was also introduced in the paper. It can help the EKF algorithm work lacking of accurate covariance of the observation noise. An optimal estimation algorithm was used to estimate the angular velocity directly from the star tracker measurements. Mathematic simulation results indicate the CMOS APS star tracker can give accurate attitude information and estimated angular rate. The method can be used as the chief attitude determination system design of low-cost satellite without gyros or be used as a backup strategy in the event of gyro failures to enhance the reliability of the attitude determination system.
	Simulation and observation of dislocation pattern evolution in the early stages of fatigue in a copper single crystal 期刊论文 OAI收割 Materials Science and Engineering a-Structural Materials Properties Microstructure and Processing, 2001, 卷号: 299, 期号: 1-2, 页码: 51-58 J. H. Yang; Y. Li; S. X. Li; C. X. Ma; G. Y. Li 收藏 \| 浏览/下载：13/0 \| 提交时间：2012/04/14 simulation and observation dislocation pattern the early stages of fatigue copper single crystal cyclic deformation localization strain