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	Periodicity Search on X-Ray Bursts of SGR J1935+2154 Using 8.5 yr of Fermi/GBM Data 期刊论文 OAI收割 The Astrophysical Journal, 2021, 卷号: 923, 页码: L30 作者: HXMT \| 收藏 \| 浏览/下载：22/0 \| 提交时间：2022/02/08 2008 1471 Astrophysics - High Energy Astrophysical Phenomena Abstract: We performed a systematic search for X-ray bursts of the SGR J1935+2154 using the Fermi Gamma-ray Burst Monitor continuous data dated from 2013 January to 2021 October. Eight bursting phases, which consist of a total of 353 individual bursts, are identified. We further analyze the periodic properties of our sample using the Lomb-Scargle periodogram. The result suggests that those bursts exhibit a period of ~238 days with a ~63.2% duty cycle. Based on our analysis, we further predict two upcoming active windows of the X-ray bursts. Since 2021 July, the beginning date of our first prediction has been confirmed by the ongoing X-ray activities of the SGR J1935+2154.
	A brushless DC motor controller with current-loop control (EI CONFERENCE) 会议论文 OAI收割 2nd Annual Conference on Electrical and Control Engineering, ICECE 2011, September 16, 2011 - September 18, 2011, Yichang, China Gao S. 收藏 \| 浏览/下载：31/0 \| 提交时间：2013/03/25 This paper presents a brushless DC motor controller with current loop control. The controller applies a complementary PWM modulation scheme to the power MOSFET. The current processor employed by the controller could detect the current flow through the motor windings accurately and convert the current to a voltage input to the error amplifier. The controller has 100% duty cycle high side conduction capability and real four quadrant torque control capability. It is able to implement a tight torque control for a DC brushless motor to satisfy the need of some servo system which calls for high bandwidth and raid dynamic response. 2011 IEEE.
	Theoretical analysis of emission characteristics of second-order distributed feedback semiconductor lasers (EI CONFERENCE) 会议论文 OAI收割 Semiconductor Lasers and Applications IV, October 18, 2010 - October 19, 2010, Beijing, China 作者: Liu Y.; Liu Y.; Qin L.; Liu Y.; Wang L. 收藏 \| 浏览/下载：28/0 \| 提交时间：2013/03/25 Based on the modified coupled-wave theory the emission characteristics including threshold gain photon density distribution in the cavity and external differential quantum efficiency for second-order DFB lasers are investigated. Numerical simulation results show that for given device structure with wavelength of 1.55 m the feedback coupling coefficient and the surface radiation coupling coefficient of the second-order grating have great influence on the emission characteristics of the device. By choosing different duty cycles of the grating we can change the two coupling coefficients which affect the emission characteristics. For an overall consideration an optimal duty cycle of 0.43 is chosen. The optimized results show that the device works without degeneracy modes and spatial burning hole. Besides the side-mode suppress ratio (SMSR) and external differential quantum efficiency reach as high as 42 dB and 47% respectively. 2010 SPIE.
	Thermal analysis for the high duty cycle PIMS accelerator 期刊论文 OAI收割 CHINESE PHYSICS C, 2010, 卷号: 34, 期号: 7, 页码: 1005-1008 作者: Liu HC(刘华昌); Peng J(彭军); Ruan YF(阮玉芳); Fu SN(傅世年); Liu, HC 收藏 \| 浏览/下载：36/0 \| 提交时间：2016/06/29 PIMS high duty cycle thermal analysis water-cooling
	Thermal analysis for the high duty cycle PIMS accelerator 期刊论文 OAI收割中国物理C, 中国物理C, 2010, 2010, 期号: 7, 页码: 1005-1008, 1005-1008 作者: Liu HC(刘华昌); Peng J(彭军); Ruan YF(阮玉芳); Fu SN(傅世年) \| 收藏 \| 浏览/下载：23/0 \| 提交时间：2015/12/14 PIMS high duty cycle thermal analysis water-cooling PIMS high duty cycle thermal analysis water-cooling
	High power 1064nm laser diode array and measuring chip temperature based on emitting spectra (EI CONFERENCE) 会议论文 OAI收割 Optoelectronic Materials and Devices III, October 27, 2008 - October 30, 2008, Hangzhou, China 作者: Wang X.; Wang L.; Wang L.; Wang L.; Wang Y. 收藏 \| 浏览/下载：21/0 \| 提交时间：2013/03/25 High power laser diode array with an emission wavelength of 1064nm is presented. The epitaxial structure is an InGaAs/GaAsP strained-compensated single-quantum well structure. The modules CW output power can reach to 56.5W at current of 80A. Because the heat capacity of st rather shorter pulse duration and lower duty cycle the average driving power in the laser chip is quite low so the heating effect cemiconductor laser is very small using pulse injection can reduce temperature rising significantly. Aould be neglected. The definite relation between lasing wavelength and chip temperature is developed. The temperature drift coefficient is 0. 45nm/K 2008 SPIE.