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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：50/0  |  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.  
Selective suppression of in situ proliferation of scyphozoan polyps by biofouling 期刊论文  OAI收割
MARINE POLLUTION BULLETIN, 2017, 卷号: 114, 期号: 2, 页码: 1046-1056
作者:  Feng, Song;  Wang, Shi-Wei;  Zhang, Guang-Tao;  Sun, Song;  Zhang, Fang
收藏  |  浏览/下载：37/0  |  提交时间：2017/04/05
油气管道建设工程对西北荒漠草原区生态环境影响的定量研究 学位论文  OAI收割
博士, 北京: 中国科学院研究生院, 2015
作者:  肖峻
收藏  |  浏览/下载：43/0  |  提交时间：2016/08/09
Rearrangeable nonblocking 88 matrix optical switches based on extended banyan network (EI CONFERENCE) 会议论文  OAI收割
作者:  Zhang Y.
收藏  |  浏览/下载：28/0  |  提交时间：2013/03/25
Based on the CROSSBAR network (CN) and the BANYAN network (BN)  8 matrix optical switch  two new rearrangeable nonblocking constructions of extended BANYAN network (EBN) are proposed for implementing 88 optical matrix switch. The interconnection characteristics of these two types of rearrangeable nonblocking EBN were studied  optical insertion loss of 4.6 dB  and the logic program for driving switching units was provided. The calculated insertion loss was 3.3 dB for 88 optical matrix switch. Silica waveguide 88 matrix optical switch was designed and fabricated according to the calculated results. The silica waveguide propagation loss of 0.1 dB/cm and waveguide-fiber coupling loss of 0.5dB/point were measured. With the fabricated 87times  cross-talk of -38 dB  polarization dependent loss of 0.4 dB  averaged switching power of 1.6 W  and switching time of 1 ms were achieved. A basic agreement between experimental results and theoretical calculated values was achieved.  
Retrieving groundwater depth in the lower reaches of Tarim River by NDVI 会议论文  OAI收割
Proceedings of SPIE - The International Society for Optical Engineering, Guangzhou, China, 2008
Shen; Qi1; Chen; Yaning2; Xu; Jianhua1; Zhang; Yan1 Source: Proceedings of SPIE - The International Society for Optical Engineering; v 7145; 2008; Geoinformatics 2008 and Joint Conference on GIS and Built Environment: Monitoring and Assessment of Natural Resources and Environments
收藏  |  浏览/下载：27/0  |  提交时间：2011/08/23
analysis of all-or-nothing hash functions 期刊论文  OAI收割
Institute of Information Science, 2008, 卷号: 24, 期号: 5, 页码: 1473-1484
Lin Pin; Wu Wenling; Wu Chuankun; Qiu Tian
  |  收藏  |  浏览/下载：19/0  |  提交时间：2010/08/20
Socio-economic driving forces of land-use change in Fuzhou, the southeastern coastal area of China 会议论文  OAI收割
2008 International Workshop on Earth Observation and Remote Sensing Applications, EORSA, Beijing, China, 2008
Wu; D.W.1; Mao; H.Y.2; Zhang; X.L.1; H.3
收藏  |  浏览/下载：34/0  |  提交时间：2011/08/23
Rearrangeable nonblocking 88 matrix optical switch based on silica waveguides and extended banyan network (EI CONFERENCE) 会议论文  OAI收割
Science and Technology of Dielectrics for Active and Passive Photonic Devices - 210th Electrochemical Society Meeting, October 29, 2006 - November 3, 2006, Cancun, Mexico
作者:  Zhang Y.
收藏  |  浏览/下载：30/0  |  提交时间：2013/03/25
Based on the CROSSBAR network (CN) and the BANYAN network (BN)  two new rearrangeable nonblocking constructions of extended BANYAN network (EBN) were proposed for implementing 88 optical matrix switch. The interconnection characteristics of these two types of rearrangeable nonblocking EBN were studied  and the driver logic program of switching units was provided. The calculated insertion loss is 3.3 dB for 88 optical matrix switch. Silica waveguide 88 matrix optical switch was designed and fabricated according to the calculated results. The silica waveguide propagation loss of 0.1 dB/cm and waveguide-fiber coupling loss of 0.5dB/point were measured out. With the fabricated 88 matrix optical switch  optical insertion loss of 4.6 dB  cross-talk of -38 dB  polarization dependent loss of 0.4 dB  averaged switching power of 1.6 W  and switching time of 1 ms were achieved. A basic agreement between experimental results and theoretical calculated values was achieved. copyright The Electrochemical Society.  
Developing of in-suit long trance profiler for testing slope error of aspherical optical Elements (EI CONFERENCE) 会议论文  OAI收割
ICO20: Optical Devices and Instruments, August 21, 2005 - August 26, 2005, Changchun, China
Zhou C.; Li H.; Chen C.; Zhou C.; Qian S.
收藏  |  浏览/下载：35/0  |  提交时间：2013/03/25
Profile error of super smooth surface of optical elements at X-ray/EUV in synchrotron radiation (SR) light beam line is described as slope error of them generally. The Long Trace Profiler (LPT) is used for testing surface slope error of SR optical elements in world generally. It is requisite to use In-suit LTP measuring surface thermal distortion of SR optical elements with high heat under high bright SR source. Authors design an In-suit LTP by means of co-path interferometer with pencil light beam. The instrument not only can be used for testing slope error of mirrors in Lab. also in situation test the distortion of mirror with high heat load at synchrotron light beam line. The device can be used to test various absolute surface figures of optical elements such as aspherieal  spherical and plane. It is needless standard reference surface. It is named by LTP-III. This paper describes its basic operating principle  optical system  mechanical constructions  DC serve motor control system  array detector  data acquisition system and computer system for controlling and data analysis of LTP-III. The Instrument has advantages of high accuracy  low cost  multifunction and wide application. Length of surface measured of optical element accuracy is 0.04 arcsec.  
On the second greedy weight for linear codes of dimension at least 4 期刊论文  OAI收割
IEEE TRANSACTIONS ON INFORMATION THEORY, 2004, 卷号: 50, 期号: 2, 页码: 354-356
作者:  Chen, W;  Klove, T
  |  收藏  |  浏览/下载：15/0  |  提交时间：2018/07/30