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	The braking index of PSR B0540-69 and the associated pulsar wind nebula emission after spin-down rate transition 期刊论文 OAI收割 Monthly Notices of the Royal Astronomical Society, 2020, 卷号: 494, 页码: 1865-1870 作者: HXMT \| 收藏 \| 浏览/下载：57/0 \| 提交时间：2022/02/08 stars: magnetic field stars: neutron pulsars: general Astrophysics - High Energy Astrophysical Phenomena Abstract: In 2011 December, PSR B054-69 experienced a spin-down rate transition (SRT), after which the spin-down power of the pulsar increased by $\sim 36{{\ \rm per\ cent}}$. About 1000 d after the SRT, the X-ray luminosity of the associated pulsar wind nebula (PWN) was found to brighten by $32\pm 8{{\ \rm per\ cent}}$. After the SRT, the braking index n of PSR B0540-69 changes from n = 2.12 to 0.03 and then keeps this value for about five years before rising to n = 0.9 in the following years. We find that most of the current models have difficulties in explaining the measured braking index. One exceptive model of the braking index evolution is the increasing dipole magnetic field of PSR B0540-69. We suggest that the field increase may result from some instabilities within the pulsar core that enhance the poloidal component at the price of toroidal component of the magnetic field. The increasing dipole magnetic field will result in the X-ray brightening of the PWN. We fit the PWN X-ray light curve by two models: one assumes a constant magnetic field within the PWN during the brightening and the other assumes an enhanced magnetic field proportional to the energy density of the PWN. It appears that the two models fit the data well, though the later model seems to fit the data a bit better. This provides marginal observational evidence that magnetic field in the PWN is generated by the termination shock. Future high-quality and high-cadence data are required to draw a solid conclusion.
	An Outlook on the Biomass Energy Development Out to 2100 in China 期刊论文 OAI收割 COMPUTATIONAL ECONOMICS, 2019, 卷号: 54, 期号: 4, 页码: 1359-1377 作者: Li, Zhihui; Deng, Xiangzheng; Chu, Xi; Jin, Gui; Qi, Wei \| 收藏 \| 浏览/下载：62/0 \| 提交时间：2020/05/19 Potential biomass energy Land use cover changes Marginal land RCPs China
	An Outlook on the Biomass Energy Development Out to 2100 in China 期刊论文 OAI收割 COMPUTATIONAL ECONOMICS, 2019, 卷号: 54, 期号: 4, 页码: 1359-1377 作者: Li, Zhihui; Deng, Xiangzheng; Chu, Xi; Jin, Gui; Qi, Wei \| 收藏 \| 浏览/下载：18/0 \| 提交时间：2020/05/19 Potential biomass energy Land use cover changes Marginal land RCPs China
	Evaluating the net value of ecosystem services to support ecological engineering: Framework and a case study of the Beijing Plains afforestation project 期刊论文 OAI收割 ECOLOGICAL ENGINEERING, 2018, 卷号: 112, 页码: 148-152 作者: Yu, Zhongqi; Liu, Xu; Zhang, Junze; Xu, Duanyang; Cao, Shixiong \| 收藏 \| 浏览/下载：35/0 \| 提交时间：2019/05/30 Ecosystem services Ecological engineering Scale effects Marginal changes Net benefits Uncertainty analysis
	Design and simulation of CMOS star sensor lens with large relative aperture and wide field (EI CONFERENCE) 会议论文 OAI收割 2011 International Conference on Electronic and Mechanical Engineering and Information Technology, EMEIT 2011, August 12, 2011 - August 14, 2011, Harbin, China Zhong X.; Jin G. 收藏 \| 浏览/下载：60/0 \| 提交时间：2013/03/25 A 50mm focal length F/1.25 Gaussian type optical system is designed in this paper which has 20field of view. Actual star image adding optical cross-talk effect of CMOS(Complementary Metal Oxide Semiconductor) detector is simulated by non-sequential ray tracing in ZEMAX optical design and analysis software to evaluate its performance. The distortion relative to image spot centriod is introduced and calculated by simulated star images which is less than 0.03% of lens in this paper. Thermal adaptability is discussed by opt-mechanic thermal analysis which shows the RMS spot radius of marginal filed changes less than 0.7m under 10C temperature gradient and changes less than 1m during homogeneous temperature changing from 40C to 40C. The results of analyses and simulations show the design of this lens can achieve the requirement of high precision CMOS star sensor well. 2011 IEEE.