中国科学院机构知识库网格系统: 检索

Introducing a special collection of papers in the Journal of High Energy Astrophysics on the Early Results of China's 1st X-ray Astronomy Satellite: Insight-HXMT 期刊论文 OAI收割
Journal of High Energy Astrophysics, 2020, 卷号: 27, 页码: 51-52
作者: HXMT

|

收藏 | 浏览/下载：56/0 | 提交时间：2022/02/08

Astrophysics - High Energy Astrophysical Phenomena Abstract: Insight-HXMT is the first Chinese X-ray astronomical mission, launched successfully on June 15, 2017, from China's Jiuquan Satellite Launch Center. Insight-HXMT was designed to have a broad energy coverage in X-rays, from 1-250 keV, with excellent timing and adequate energy resolution at soft X-rays, and the largest effective area at hard X-rays. This allows, in particular, to observe bright sources like X-ray binaries (XRBs) in their bright/outburst states with high cadence and high statistics at hard and soft X-rays at once. It was then expected that the Insight-HXMT mission will bring us new insights regarding the characteristics of several source classes. Examples include characterizing High-Mass X-ray Binaries (HMXBs) and the outburst evolution of Low-Mass X-ray Binaries (LMXBs). For instance, in HMXB systems, the region around their Alfven radius that is responsible to determine whether accretion or propeller occurs, or the region around the NS magnetic pole where the intense X-rays are supposed to be produced are specially appealing targets of study. For the LMXBs, the evolution the outburst and the properties of the compact objects themselves are obvious priority targets for Insight-HXMT. Due to the broad coverage in energy, Insight-HXMT is specially well suited to study the influence of thermonuclear (type-I) X-ray bursts upon the surrounding environment.

Insight-HXMT observations of Swift J0243.6+6124: the evolution of RMS pulse fractions at super-Eddington luminosity 期刊论文 OAI收割
Monthly Notices of the Royal Astronomical Society, 2020, 卷号: 497, 页码: 5498-5506
作者: HXMT

|

收藏 | 浏览/下载：50/0 | 提交时间：2022/02/08

stars: neutron pulsars: individual: Swift J0243.6+6124 X-rays: binaries Astrophysics - High Energy Astrophysical Phenomena Abstract: Based on Insight-HXMT data, we report on the pulse fraction evolution during the 2017-2018 outburst of the newly discovered first Galactic ultraluminous X-ray (ULX) source Swift J0243.6+6124. The pulse fractions of 19 observation pairs selected in the rising and fading phases with similar luminosity are investigated. The results show a general trend of the pulse fraction increasing with luminosity and energy at supercritical luminosity. However, the relative strength of the pulsation between each pair evolves strongly with luminosity. The pulse fraction in the rising phase is larger at luminosity below 7.71 × 10³⁸ erg s^-1, but smaller at above. A transition luminosity is found to be energy independent. Such a phenomenon is first confirmed by Insight-HXMT observations and we speculate that it may have relation with the radiation-pressure-dominated accretion disc.

In-orbit Demonstration of X-Ray Pulsar Navigation with the Insight-HXMT Satellite 期刊论文 OAI收割
The Astrophysical Journal Supplement Series, 2019, 卷号: 244, 页码: 1
作者: HXMT

|

收藏 | 浏览/下载：17/0 | 提交时间：2022/02/08

pulsars: general techniques: miscellaneous Astrophysics - Instrumentation and Methods for Astrophysics Abstract: In this work, we report the in-orbit demonstration of X-ray pulsar navigation with Insight-Hard X-ray Modulation Telescope (Insight-HXMT) Satellite, which was launched on 2017 June 15. The new pulsar navigation method Significance Enhancement of Pulse-profile with Orbit-dynamics is adopted to determine the orbit with observations of only one pulsar. In this test, the Crab pulsar is chosen and observed by Insight-HXMT from 2017 August 31 to September 5. Using the five-day long observation data, the orbit of Insight-HXMT is determined successfully with the three telescopes onboard: High Energy X-ray Telescope, Medium Energy X-ray Telescope, and Low Energy X-ray Telescope, respectively. By combining all the data, the position and velocity of the Insight-HXMT are pinpointed to within 10 km (3ҩ and 10 m s^-1 (3ҩ, respectively.

Luminescence and energy transfer in Ca3Sc2Si 3O12:Ce3+,Mn2+ white LED phosphors (EI CONFERENCE) 会议论文 OAI收割
作者: Luo Y.; Zhang J.; Zhang J.; Zhang J.; Wang X.

收藏 | 浏览/下载：41/0 | 提交时间：2013/03/25

Expanded emission spectra ranging from green to red are reported in Ca 3Sc2Si3O12 (CSS):Ce 3+ Mn2+ silicate garnets. Mn2+ may occupy Ca2 site (Mn2+(I)) to generate a yellow emission band at 574 nm or Sc3 site (Mn2+(II)) with red emission band at 680 nm. Efficient energy transfers from the green emitting Ce3+ to both Mn2+(I) and Mn2+(II) occur upon blue excitation into Ce3+. Concentration dependence of Mn2+ emission is analyzed based on Ce3+-Mn2+ energy transfer steady state rate equations and fluorescence lifetimes. Energy transfer efficiency (nT) and rate (W) are calculated with values as high as 45% and 14.01106 s-1 respectively. 2011 Elsevier B.V.

Field-line coupling interference prediction of LCD module in high-power TEA CO2 laser system (EI CONFERENCE) 会议论文 OAI收割
2012 International Conference on Optoelectronics and Microelectronics, ICOM 2012, August 23, 2012 - August 25, 2012, Changchun, China
Ge X.; Li X.

收藏 | 浏览/下载：21/0 | 提交时间：2013/03/25

In high power TEA CO2 laser system liquid crystal display (LCD) module is a key device for display and control functions. Because of laser's harsh electromagnetic environment LCD module coupled to the electromagnetic interference easily leading to not work normally. This paper analyzed the interference coupling mechanism. On the basis of the analysis results LCD module's field-line coupling is calculated by Taylor form's BLT equation. The calculation result is verified by experiment. The results show that due to the field-line coupling the data line of LCD module existed interference voltage interference voltage value is 1V. The interference voltage is larger than the LCD module's noise margin. LCD module must shield the interference. 2012 IEEE.

PID control of glucose concentration in subjects with type 1 diabetes based on a simplified model: An in silico trial (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: Yu L.

收藏 | 浏览/下载：34/0 | 提交时间：2013/03/25

An artificial pancreas system (APS) mimics the function of a real pancreas through monitoring a diabetic's blood glucose and administering the right dose of insulin via an automatic control loop. It is hailed as a promising cure of diabetes though this technology is still years away from commercial use due to a few technological bottlenecks. The simulation model of insulin-glucose metabolism of type 1 diabetes mellitus (T1DM) is an essential part of APS. In order to simplify the parameter identification task so that the model can be implemented electronically with ease this paper presents a simplified model based on Routh approximation model reduction method. The results show that the approximation error between the simplified model and the original model is so small that can be neglected. Based on the simplified model a PID controller is designed to maintain normoglycemia (90mg/dl) in subjects with T1DM. The in silico simulation results show that the glucose concentration is controlled well the risk of hyperglycemia and hypoglycemia is reduced a lot. This suggests that the simplified model describes the insulin-glucose metabolism process accurately and the PID control algorithm is well-suitable to guide the further development of an APS. 2012 IEEE.

Energy transfer in Y3Al5O12:Ce 3, Pr3+ and CaMoO4:Sm3, Eu 3 phosphors (EI CONFERENCE) 会议论文 OAI收割
作者: Wang L.; Wang X.-J.; Zhang X.; Zhang X.; Zhang X.

收藏 | 浏览/下载：40/0 | 提交时间：2013/03/25

Non-radiative energy transfers (ET) from Ce3 to Pr3+ in Y3Al5O12:Ce3 Pr3+ and from Sm3 to Eu3 in CaMoO4:Sm3 Eu3 are studied based on photoluminescence spectroscopy and fluorescence decay patterns. The result indicates an electric dipoledipole interaction that governs ET in the LED phosphors. For Ce3 concentration of 0.01 in YAG:Ce3 Pr3+ the rate constant and critical distance are evaluated to be 4.510-36 cm 6 s-1 and 0.81 nm respectively. An increase in the red emission line of Pr3+ relative to the yellow emission band of Ce 3 on increasing Ce3 concentration is observed. This behavior is attributed to the increase of spectral overlap integrals between Ce3 emission and Pr3+ excitation due to the fact that the yellow band shifts to the red spectral side with increasing Ce3 concentration. In CaMoO4:Sm3 Eu3 Sm 3Eu3 transfer occurs from 4G5/2 of Sm3 to 5D0 of Eu3. The rate constant of 8.510-40 cm6 s-1 and the critical transfer distance of 0.89 nm are evaluated. 2010 Elsevier B.V. All rights reserved.

Brazing RB-SiC used in large aperture space optical system (EI CONFERENCE) 会议论文 OAI收割
2011 International Conference on Materials and Products Manufacturing Technology, ICMPMT 2011, October 28, 2011 - October 30, 2011, Chengdu, China
Zhang B.; Zhang Z.

收藏 | 浏览/下载：27/0 | 提交时间：2013/03/25

Because of the sic material's superior optical characteristic machine characteristic and hot characteristic it becomes currently the space big aperture reflector choose firstly1. For larger aperture sic mirror it is not economical and safe to make the monolithic body directly 2 3. The SiC mirror brazed assembly with several segments can solve these problems. In this paper one 600 mm sic plane mirror as demonstration welded with 3 radial segments is roughly grinded to the required figure at first then the mirror is finely grinded and polished by the technology of CCOS the mirror figure error is less than 1/20 ( = 632.8nm) in RMS finally. The problems of the preferential removal near braze joint are solved. The methods of reducing the residual stress of mirror are discussed. At last some measurements and experiments are carried on and the results conclude that the brazed SiC mirror can meet the requirement of large aperture optical systems. (2011) Trans Tech Publications.

Determination of the controlled landing trajectory of Chang'E-1 satellite and the coordinate analysis of the landing point on the Moon 期刊论文 OAI收割
CHINESE SCIENCE BULLETIN, 2010, 卷号: 55, 期号: 13, 页码: 1240-1245
作者: Li JinLing; Guo Li; Qian ZhiHan; Jiang DongRong; Zheng WeiMin

收藏 | 浏览/下载：38/0 | 提交时间：2015/08/18

China's Lunar Exploration Project Chang'E-1 satellite controlled landing on the Moon trajectory measurement VLBI

Correction of the non-uniformity for multi-TDICCD mosaic camera on FPGA (EI CONFERENCE) 会议论文 OAI收割
2010 International Conference on E-Product E-Service and E-Entertainment, ICEEE2010, November 7, 2010 - November 9, 2010, Henan, China
Zhu H.; Xue X.; Ma T.; Li H.; Si G.; Guo Y.

收藏 | 浏览/下载：56/0 | 提交时间：2013/03/25

To solve the non-uniformity problem of multi Time Delay Integral Charge Couple Device (TDICCD) mosaic camera several common non-uniformity correction methods are discussed. Secondly a non-uniformity correction algorithm is proposed and implemented on Field-Programmable Gate Array (FPGA) platform. Firstly the correction algorithm is designed. Finally the generation and definition of non-uniformity are introduced considering the fix-point processing ability of FPGA the correction algorithm is optimized properly and implemented on FPGA. The experimental results indicate that the non-uniformity can be decreased from 8.3%to 2.0% in 1s for 3-TDICCD mosaic camera's images with the proposed correction algorithm at 96TDI stage proving that this correction algorithm is of high real-time performance good practicality and satisfies the requirements of the target system. 2010 IEEE.