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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：55/0 \| 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.
	An energy-based position control and asymptotic stability analysis for manipulator handling a flexible payload (EI CONFERENCE) 会议论文 OAI收割 10th World Congress on Intelligent Control and Automation, WCICA 2012, July 6, 2012 - July 8, 2012, Beijing, China 作者: Wang Z.; Li Y.; Li Y.; Li Y.; Li Y. 收藏 \| 浏览/下载：50/0 \| 提交时间：2013/03/25 In this paper an exact dynamic model of manipulator handling a flexible payload is derived by Hamiton's principle. On the basis of the distributed parameter model a position controller is designed by using Lyapunov function related to the total energy of the system. The controller can achieve the given desired link angles and suppress the vibrations of flexible payload. Using the LaSalle's invariance principle and the characteristic of the differential operator the asymptotic stability in the neighbor-hood of the desired states of the closed-loop system is proved. The effectiveness of the control strategy proposed is supported by some simulations. 2012 IEEE.
	Capability of the extended state observer for minimum phase plants with unknown orders and uncertain relative degrees (EI CONFERENCE) 会议论文 OAI收割 31st Chinese Control Conference, CCC 2012, July 25, 2012 - July 27, 2012, Hefei, China Zhao C.; Yang X.; Xiong J.; Lin X. 收藏 \| 浏览/下载：19/0 \| 提交时间：2013/03/25 The observing capability of the active disturbance rejection control (ADRC) for the minimum phase plants with unknown orders and uncertain relative degrees is discussed in this paper. The frequency performance of the linear extended state observer (LESO) is analyzed. It is proved that ESO can estimate the required states at the designed speed in spite of a large range of uncertainties. Finally the results are verified by simulations. 2012 Chinese Assoc of Automati.
	Adaptive backstepping control of a dual-manipulator cooperative system handling a flexible payload (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 Y.; Li Y.; Li Y.; Li Y. 收藏 \| 浏览/下载：28/0 \| 提交时间：2013/03/25 Two manipulators handling a flexible payload are studied based on adaptive backstepping control theory. Considering the complexity of the dynamic model the obtained model is divided into a slow subsystem describing the large rigid motion and a fast subsystem expressing the elastic vibration by singular perturbation theory. A cooperative controller is designed based on adaptive backstepping control. The slow subsystem can complete system trajectory tracking performance. The fast subsystem can suppress the elastic vibration of the system. Stability of the system is proved by using Lyapunov stability theory. The validity of the proposed scheme is demonstrated by simulations. 2010 IEEE.
	Simulations and experimental studies of diffuser/nozzle pumps (EI CONFERENCE) 会议论文 OAI收割 4th International Symposium on Precision Mechanical Measurements, August 25, 2008 - August 29, 2009, Hefei/Jiuhua Mountain, Anhui, China 作者: Li W.; Li W. 收藏 \| 浏览/下载：30/0 \| 提交时间：2013/03/25 An investigation of diffuser/nozzle micropumps is presented. Numerical simulations are done using CFD program ANSYS/Flotran. The simulations show when the opening angel is small the flow in the diffuser/nozzle is steady the mass flow is increasing with the adding opening angle. But when the opening angel continues increasing the pressure grads will be bigger than zero. It means that the static pressure is gradually going up along the diverging direction. The fluid near the wall stops flowing because the velocity decreases rapidly and the dynamic pressure is not big enough to overcome the increasing of the static pressure. Finally the fluid flows reversely from the backward position of higher pressure area this makes the separation flow of fluid the diffuser is full of reverse fluid. And this results in the dropping of mass flow at last. The simulations also show that the performance of diffuser with a round inlet is better than that with a sharp inlet. The mass flow of micropumps with different opening angles different inlets are measured. The experimental results agree well with the simulations. 2008 SPIE.
	The Effects of Gene Flow on Reinforcement 期刊论文 OAI收割 Evolution, 1997, 卷号: 51, 期号: 6, 页码: 1764-1772 作者: Maria R. Servedio; Mark Kirkpatrick \| 收藏 \| 浏览/下载：12/0 \| 提交时间：2017/07/26 Gene Flow Isolating Mechanism Migration Peripheral Isolation Reinforcement Simulations.