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Integrated precise orbit determination of Shenzhou IV unmanned spacecraft

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Science china(Technological Sciences) 2004年第5期47卷 518-525页

作者： L Congmin1,2, GU Yidong3. LIN Baojun3.& GUO Jiong3.1. center for Space Science and Applied Research, Chinese Academy of Sciences, beijing 100080, china 2. Graduate School of the Chinese Academy of Sciences, beijing 10003., china 3. General Establishment of Space Science and Application, Chinese Academy of Sciences, beijing 100080, china Correspondence should be addressed to L Congmin center for Space Science and Applied Research Chinese Academy of Sciences Beijing China Graduate School of the Chinese Academy of Sciences Beijing China General Establishment of Space Science and Application Chinese Academy of Sciences Beijing China

Considering the characteristic orbit of Shenzhou IV spacecraft and the advantages and disadvantages of several types of domestic orbit measurements, a scheme of IPOD is determined, which uses GPS, SLR and USB observation data jointly plus precise ionosphere corrections to GPS observation data. IPOD system and mathematic models of OD are introduced. The results of different joint OD are analyzed using true observation data, and show that radial accuracy is better than 2 m.

关键词： Shenzhou IV unmanned spacecraft integrated precise orbit determination GPS SLR USB.

Absolute radiometric calibration of CBERS-02 IRMSS thermal band

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Science china(Technological Sciences) 2005年第S2期48卷 72-90页

作者： ZHANG Yong1,2,3. GU Xingfa1,3.4, YU Tao1,3. ZHANG Yuxiang5, CHEN Liangfu1,3. LI Xiaoying1,2,3. LI Xiaowen1,3.& HE Liming6 1. State Key Laboratory of Remote Sensing Science, Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and beijing Normal University, beijing 100101, china 2. Graduate University of Chinese Academy of Sciences, beijing 10003., china 3. The center for National Spaceborne Demonstration, beijing 100101, china 4. Institut National de la Recherche Agronomique, Climat Sol Environnement, 84914 Avignon, France 5. National Satellite Meteorological center, beijing 100081, china 6. State Environmental Protection Administration, beijing 100029, china State Key Laboratory of Remote Sensing Science Beijing Normal University Chinese Academy of Sciences Beijing 100101 China Graduate University Chinese Academy of Sciences Beijing 100039 China center for National Spaceborne Demonstration Beijing 100101 China National Satellite Meteorological center Beijing 100081 China Institut National de la Recherche Agronomique Climat Sol Environnement 84914 Avignon France State Environmental Protection Administration Beijing 100029 China

Based on the laboratory calibration before launch of CBERS-02 IRMSS thermal infrared channel, the onboard blackbody calibration, the radiometric cross- calibration against TERRA MODIS corresponding channel and the in-flight field calibration at Lake Qinghai: water surface radiometric calibration test site of china on Aug. 17, 2004 are carried out in this research. When making onboard blackbody calibration of CBERS-02 IRMSS, it is necessary to understand inside structures and light path in IRMSS camera and receive and process calibration blackbody signals at normal and high temperatures. Onboard blackbody calibration results of each detector are very important to relative radiometric calibration of images processing and absolute radiometric calibration of each detector. In-flight field calibration mainly contains field experiments, obtaining synchronous images, spectrum marching and MODTRAN radiative transmi- ssion computation. Radiometric cross-calibration of CBERS-02 IRMSS thermal band against TERRA MODIS selected 6 times synchronous images of two sensors passing through Lake Qinghai and Lake Taihu from August to December, 2004 to compute the cross calibration data. Combining the in-flight field calibration and radiometric cross calibration data, the absolute radiometric calibration coefficients are calculated by the linear regression method. This new calibration model can obviously control the radiometric calibration uncertainties aroused by the single point method used in the in-flight calibration of CBERS-02 IRMSS, this kind of sensors cannot receive the cosmic background radiation. In this research, the radiometric calibration coefficients obtained through the linear regression model are 8.53.(gain, unit: DN/W m?2sr?1μm?1) and 44.92 (offset, unit: DN).

关键词： CBERS-02 IRMSS thermal band in-flight field calibration onboard blackbody calibration cross calibration.

Investigation of integrons/cassettes in antimicrobial-resistant Escherichia coli isolated from food animals in china

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Science china(Life Sciences) 2010年第5期53卷 613-619页

作者： SONG Li1,NING YiBao1,SHEN JianZhong2,FAN XueZheng,ZHANG ChunPing1,YANG ChengHuai1 & HAN JianFeng3.1 china Institute of Veterinary Drug control,beijing 100081,china 2 china Agricultural University,beijing 100094,china 3.china center for Disease control and Prevention,beijing 100050,china china Institute of Veterinary Drug control Beijing China china Agricultural University Beijing China china center for Disease control and Prevention Beijing China

In this study,3.6 Escherichia coli isolates from food animals collected during the last four decades in china were characterized using antimicrobial susceptibility testing and screening for integrons/*** inhibitory concentration(MIC) testing indicated that the antimicrobial resistance of *** has increased since the *** findings of this study present a warning to veterinary practitioners about the excessive use of antimicrobials,and suggest the necessity for surveillance and control of antimicrobial resistance in veterinary clinical medicine in china.

关键词： E.coli Antimicrobial resistance integron/cassette last four decades

Timeliness evaluation of task-oriented networked space-based information system

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Journal of Systems Engineering and Electronics 2011年第4期22卷 621-627页

作者： Chen Chen 1,2,and Jie Chen 2,3.1.Department of Automation,Tsinghua University,beijing 100084,P.R.china 2.School of Automation,beijing Institute of Technology,beijing 100081,P.R.china 3.Complex System Intelligent control and Decision,Ministry of Education,beijing 100081,P.R.china Department of Automation Tsinghua University Beijing 100084 P. R. China School of Automation Beijing Institute of Technology Beijing 100081 P. R. China School of Automation Beijing Institute of Technology Beijing 100081 P. R. China Complex System Intelligent control and Decision Ministry of Education Beijing 100081 P. R. China

Task-oriented networked information system is an integrated information system which builds on multi-satellite networking to accomplish one or more tasks. In the background of emer- gency relief for applications, system working flow and response process are analyzed, and a timeliness effectiveness evaluation index system is constructed at multi-task level. The effectiveness is a measurement of promptness of information return. In evalua- tion process, system performance and tasks are associated, then an evaluation model based on efficacy function is established, and different evaluation criteria are selected for different tasks. A distributed simulation system is constructed, and the execution of task is decomposed. The simulation platform provides a comprehensive data source for evaluation. The results are easy to compare with each other, which reflects system time efficiency in different satellites networks and provides actual systems with basis and reference for design and application.

关键词： timeliness efficacy function space-based informationsystem simulation system.

In vivo and in vitro antiviral activity of hyperoside extracted from Abelmoschus manihot (L) medik

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Acta Pharmacologica Sinica 2007年第3期28卷 404-409页

作者： Lin-lin WU~(2,3. Xin-bo YANG~(3.6) Zheng-ming HUANG~(4,6) He-zhi LIU~5 Guang-xia WU~22 Research center for Eco-Environmental Sciences,Chinese Academy of Sciences,beijing 100085,china 3.3.1 Hospital of PLA,beijing 100853.china 4 3.2 Hospital of PLA,beijing 10003.,china 5 Department of General Logistics of PLA,Institute for Drug and Instrument control of Health,beijing 100071,china Research center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing China 3.1 Hospital of PLA Beijing China 3.2 Hospital of PLA Beijing China Department of General Logistics of PLA Institute for Drug and Instrument Control of Health Beijing China

Aim:To assess the anti-hepatitis B virus（HBV）effect of hyperoside extractedfrom Abelmoschus manihot（L）***:The human bepatoma HepG2.2.15 cell culture system and duck hepatitis B virus（DHBV）infection modelwere used as in vivo and in vitro models to evaluate the anti-HBV ***:In the cell model,the 50% toxic concentration of hyperoside was 0.115 g/L;themaximum nontoxic concentration was 0.05 g/L,On the maximum nontoxicconcentrations,the inhibition rates of hyperoside on HBeAg and HBsAg in-the2.2.15 cells were 86.41% and 82.27% on d 8,*** the DHBV infectionmodel,the DHBV-DNA levels decreased significantly in the treatment of ***-1·d-1and 0.10 g·kg-1dosage groups of hyperoside（P3.***:Theseresults suggested that hyperoside is a strong inhibitor of HBsAg and HBeAgsecretion in 2.2.15 cells and DHBV-DNA levels in the HBV-infected duck model.

关键词： hyperoside hepatitis B virus duck hepatitisB virus antiviral agents

New adaptive quasi-sliding mode control for nonlinear discrete-time systems

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Journal of Systems Engineering and Electronics 2008年第1期19卷 154-160页

作者： Wang Weihong1,2 & Hou Zhongsheng3.1. School of Tra?c and Transportation, beijing Jiaotong Univ., beijing 100044, P. R. china 2. Dept. of Automation, Taiyuan Univ. of Science & Technology, Taiyuan 03.024, P. R. china 3. Advanced control Systems Lab, School of Electronics and Information Engineering, beijing Jiaotong Univ., beijing 100044, P. R. china School of Traffic and Transportation Beijing Jiaotong Univ. Beijing 100044 P. R. China Dept. of Automation Taiyuan Univ. of Science & Technology Taiyuan 030024 P. R. China Advanced control Systems Lab School of Electronics and Information Engineering Beijing Jiaotong Univ. Beijing 100044 P. R. China

A new adaptive quasi-sliding mode control algorithm is developed for a class of nonlinear discrete-time systems, which is especially useful for nonlinear systems with vaguely known dynamics. This design is model-free, and is based directly on pseudo-partial-derivatives derived on-line from the input and output information of the system using an improved recursive projection type of identification algorithm. The theoretical analysis and simulation results show that the adaptive quasi-sliding mode control system is stable and convergent.

关键词： quasi-sliding mode control adaptive control model-free control pseudo-partial-derivative

Final Temperature Prediction Model of Molten Steel in RH-TOP Refining Process for IF Steel Production

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Journal of Iron and Steel Research International 2012年第3期19卷 1-5页

作者： WANG Yu-nan1, BAO Yan-ping1, CUI Heng2, CHEN Bin3. JI Chen-xi3.(1. State Key Laboratory of Advanced Metallurgy, University of Science and Technology beijing, beijing 100083. china 2. Engineering Research Institute, University of Science and Technology beijing, beijing 100083. china 3. Shougang Research Institute of Technology, beijing 100041, china) State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing Beijing China Engineering Research Institute University of Science and Technology Beijing Beijing China Shougang Research Institute of Technology Beijing China

In order to precisely control the final temperature of molten steel in RH （Ruhrstahl Heraeus）-TOP blowing refining, the final temperature prediction models of molten steel in RH-TOP blowing refining process for Interstitial Free （IF） steel production were established under the condition of oxygen blowing and non-oxygen blowing respec- tively. The results show that the beginning molten steel temperature of refining and the amount of added scrap were influential factors, the baking temperature in vacuum chamber was a factor that had small influence. When the model was operated, the hitting probability was above 95%（under the condition of both oxygen blowing and non-oxygen blo- wing） of prediction deviation ±10℃. The accuracy is analyzed.

关键词： RH-TOP molten steel temperature prediction model

Target selection and transfer trajectories design for exploring asteroid mission

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Science china(Technological Sciences) 2010年第4期53卷 1150-1158页

作者： CUI PingYuan1,QIAO Dong1,CUI HuTao2 & LUAN EnJie3.1 School of aerospace Engineering,beijing Institute of Technology,beijing 100081,{3. 2 Harbin Institute of Technology,Harbin 150001,{3. 3.National Defense Science and Industry Bureau,beijing 100048,{3. School of aerospace Engineering Beijing Institute of Technology Beijing China Harbin Institute of Technology Harbin China National Defense Science and Industry Bureau Beijing China

Technique of target selection and profiles of transfer trajectory for Chinese asteroid exploring mission are studied systemically.A complete set of approaches to selecting mission targets and designing the transfer trajectory is ***,when selecting a target for mission,some factors regarded as the scientific motivations are ***,when analyzing the accessibility of targets,instead of the classical strategy,the multiple gravity-assist strategy is *** suitable and possible targets,taking into account scientific value and technically feasible,are obtained via selection and *** designing the transfer trajectory for exploring asteroid mission,an approach to selecting gravity-assist celestial body is ***,according to the mission constraints,the trajectory profile with 2-years △V-EGA for exploring asteroid is *** analyzing the trajectory profile,unexpected result that the trajectory would pass by two main-belts asteroids is ***,the original proposal is extended to the multiple flybys *** adds the scientific return for asteroid mission.

关键词： exploring asteroid target selection multiple flybys transfer trajectory

A new navigation approach of terrain contour matching based on 3.D terrain reconstruction from onboard image sequence

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Science china(Technological Sciences) 2010年第5期53卷 1176-1183页

作者： LI LiChun1,2,YU QiFeng2,SHANG Yang2,YUAN Yun2,LU HongWei3.& LIU XiaoLin4 1 beijing aerospace control {3.,beijing 100094,china 2 College of aerospace and Material Engineering,National University of Defense Technology,Changsha 410073.china 3.Equipment Research Institute of PLA’s Second Artillery,beijing 100085,china 4 College of Mechatronic Engineering and Automation,National University of Defense Technology,Changsha 410073.china beijing aerospace control {3. Beijing China College of aerospace and Material Engineering National University of Defense Technology Changsha China Equipment Research Institute of PLA’s Second Artillery Beijing China College of Mechatronic Engineering and Automation National University of Defense Technology Changsha China

This article presents a passive navigation method of terrain contour matching by reconstructing the 3.D terrain from the image sequence(acquired by the onboard camera).To achieve automation and simultaneity of the image sequence processing for navigation,a correspondence registration method based on control points tracking is proposed which tracks the sparse control points through the whole image sequence and uses them as correspondence in the relation geometry ***,a key frame selection method based on the images overlapping ratio and intersecting angles is explored,thereafter the requirement for the camera system configuration is *** proposed method also includes an optimal local homography estimating algorithm according to the control points,which helps correctly predict points to be matched and their speed ***,the real-time 3.D terrain of the trajectory thus reconstructed is matched with the referenced terrain map,and the result of which provides navigating *** digital simulation experiment and the real image based experiment have verified the proposed method.

关键词： terrain contour matching vision-based navigation 3.D reconstruction control points key frame registration optimal local homography