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	A New Set of Parameters of High-Mass X-ray Binaries Found with their Cyclotron Lines 期刊论文 OAI收割 arXiv e-prints, 2018 作者: Zhang, Chengmin; Taani, Ali; Chaty, Sylvain; Karino, Shigeyuki; Song, Liming \| 收藏 \| 浏览/下载：89/0 \| 提交时间：2019/07/12 Astrophysics - High Energy Astrophysical Phenomena Abstract: We have derived new physical quantities for several High-Mass X-ray Binaries (HMXBs) with supergiant (SG) companions through their cyclotron lines. The parameters are: the terminal velocity of the wind, the mass loss rate of the donor, the effective temperature and the magnetic fields. These parameters influence significantly the improvement of the model of accretion. In spite of the variety of their observational properties, the corresponding magnetic field is around B ~ 10^12 G. This result can be constrained by the effects on stellar evolution. In addition, we have performed a segmentation in the parameter space of donors intended for several SG-HMXB listed in our sample set. The parameter space can be categorized into five regimes depending on the possibility of disk formation associated with accretion from the stellar wind. This can give a quantitative clarification of the observed variability and the properties of these objects. We show that, when these systems come into the direct accretion region, systems with corresponding parameters can emit X-rays.
	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.
	United steering of control moment gyros for small satellite with limited gimbal rate (EI CONFERENCE) 会议论文 OAI收割 2010 IEEE International Conference on Information and Automation, ICIA 2010, June 20, 2010 - June 23, 2010, Harbin, Heilongjiang, China Xu K.; Jin G.; Chen C. 收藏 \| 浏览/下载：25/0 \| 提交时间：2013/03/25 Single Gimbal Control Moment Gyroscopes (SGCMG) can could provide large control torque and quick attitude maneuver rate to small satellites without any increase in power volume and mass which will help small satellites become more powerful. Singularity avoidance and failure steering are two important problems to SGCMGs and also the main focus in this field. A new united steering law for SGCMGs with capabilities of singularity avoidance and quick transition of singularity surfaces is developed in this paper. To ensuring the existence of null motion the commanded output of controller was changed real-timely as the variation of singularity measurement of SGCMGs which can avoid the gimbal angle rate saturation. This developed steering law could help the SGCMGs provide real-time control toques in spite of limitation of gimbal angle rate. Simulation analysis is conducted for a certain 4-SGCMG system mounted on a small satellite. Simulation results indicate that the steering law is very effective in singularity avoidance. 2010 IEEE.
	Land use dynamics and landscape change pattern in Hetao irrigation district, Inner Mongolia, China 会议论文 OAI收割 6th International Symposium on Digital Earth: Data Processing and Applications, Beijing, China, September 9, 2009 - September 12,2009 Zhang, Yinhui; Luo, Yi; Zhao, Wenwu 收藏 \| 浏览/下载：33/0 \| 提交时间：2014/12/07 This study analyzed spatial and temporal changes in land use in an irrigation district covering an area of 1.7 million ha in Northern China by GIS analyses and also investigated changes in landscape pattern using the landscape structure analysis program FRAGSTATS over the study period from 1986 to 2000. The decreases in farmland and the increases in grassland area mainly resulted from the policy of grain for green and converting slope farmland into pasture from China government. In spite of the efforts to conserve the fragile ecosystem the land degradation including soil salinization and grassland degradation was spreading rapidly. The area of alkali-saline land increased by 22493 ha and about 50555 ha of dense grassland degraded into mid-density grassland. In terms of landscape fragmentation both farmland and dense grassland showed the tendency of increased fragmentation. Both adverse natural conditions and human activities are responsible for the land degradation expansion in Hetao irrigation district but the root causes are increasing population pressure and irrational human activities such as flooding irrigation method and over-grazing. To prevent land degradation from spreading population control and improvement of the management are prerequisite approaches. 2010 SPIE.
	TWO-NUCLEON ABSORPTION MECHANISM OF PION IN FLIGHT 期刊论文 OAI收割 A Monthly Journal of Science, 1982, 期号: 6, 页码: 939-943 作者: Jiang HQ(姜焕清); Li YG(李扬国) 收藏 \| 浏览/下载：20/0 \| 提交时间：2015/12/10 spite earlier stopped inclusive discussion absorbed encouraging gross momentum slowdown