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Long March Launch Vehicles Promote Quick and Sound Development of Satellite Applications

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Aerospace china 2011年第1期12卷 14-17页

作者： Hao Zhaoping china Academy of Launch Vehicle technology china Academy of Launch Vehicle technology

INTRODUCTION Launch vehicles are a precondition and main carrier for space activities for human *** development have directly promoted the technology of satellite applications,manned spaceflight,deep space exploration,and promoted the development of communication,navigation,environmental monitoring,resource exploitation,scientific research and so on.

关键词： high Long March Launch Vehicles Promote Quick and Sound Development of Satellite Applications

A Principle Design for Global Integrity of COMPASS

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A Principle Design for Global Integrity of COMPASS

第三届中国卫星导航学术年会

作者： Lang Bian*, Yansong Meng, Xiaoliang Wang, Wenshan Liu, Xiaoxia Tao, Xiaoping Qian, Lixin Zhang china Academy of space {2. (Xi’an) Xi’an china 710100

Considering the difficulty of implementation on global integrity of COMPASS for the constrain of global deployment of monitor station, this paper proposed a principle design for global integrity of COMPASS based on combination of pace and ground, by managing Signal-in-space Accuracy （SISA） and monitoring the integrity anomaly of satellite. An implementation scheme of integrity monitoring of satellite clock and navigation signal onboard is provided, with theory analysis and simulation study of integrity monitor in case of malfunction of clock error, clock rate and clock acceleration, also the distorted of PN code. Simulation results indicated that the integrity monitor of step and ramp error of clock can be realized by using the method based on the difference of main-backup clock phase difference and Inter-Satellite Ranging （ISR） , and the integrity monitor of distorted PN code can be realized by using SQM2. algorithm.

关键词： COMPASS Global integrity Inter-satellite link Autonomous monitoring

Observability Analysis of Autonomous navigation System of Interplanetary spacecraft

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Observability Analysis of Autonomous Navigation System of In...

2.09中国控制与决策会议

作者： Xiaohua Chang~1,Pingyuan Cui,Hutao Cui 1.Deep space Exploration Research Center,Harbin Institute of technology,Harbin 150080,{2.

＜正＞In this paper,an autonomous navigation scheme for interplanetary spacecraft based on the Sun line-of-sight vector measurement is *** order to prove that the directional data alone can completely determine the spacecraft orbit,an analytical observability analysis is implemented through the partial derivative of the measurement ***,a numerical local observability analysis is derived from the Lie *** presented is a global observability analysis by introducing the condition number of the measurement ***,simulation results demonstrate the validity of the proposed navigation algorithm.

关键词： Autonomous navigation Observability Condition Number

Rendezvous to asteroid with highly uncertain ephemeris: Hayabusa2.s Ryugu-approach operation result

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Astrodynamics 2020年第2期4卷 137-147页

作者： Yuichi Tsuda Hiroshi Takeuchi Naoko Ogawa Go Ono Shota Kikuchi Yusuke Oki Masateru Ishiguro Daisuke Kuroda Seitaro Urakawa Shin-ichiro Okumura Hayabusa2.Project Team Institute of space and Astronautical Science Japan Aerospace Exploration AgencySagamihara252-5210Japan Research and Development Directorate Japan Aerospace Exploration AgencySagamihara252-5210Japan Research and Development Directorate Japan Aerospace Exploration AgencyTsukuba305-8505Japan Seoul National University Seoul08826Republic of Korea Okayama Observatory Kyoto UniversityAsakuchi719-0232Japan Japan spaceguard Association Bisei714-1411Japan 不详

This paper describes the guidance and navigation technique used by Hayabusa2.for the asteroid rendezvous operation to reach *** operation results,including the achieved guidance and navigation performance,are also *** assessment and navigation teams worked closely to provide reliable navigation solutions with a short solution delivery *** the uncertainty of the Ryugu’s ephemeris was considerable before Hayabusa2.s arrival,a combination of radiometric-optical hybrid navigation and a stochastic-constrained optimum guidance method was able to achieve an accuracy of less than 100 m and 1 cm/s,and the arrival was precisely timed.

关键词： solar system exploration sample return optical navigation trajectory optimization spacecraft guidance

A Method on Constellation On-orbit Backup of Regional navigation Satellite System

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A Method on Constellation On-orbit Backup of Regional Naviga...

第三届中国卫星导航学术年会

作者： *Feng Laiping1,2. Jiao Wenhai3, Jia Xiaolin2. Wu Xianbing2. Ren Kai1,4(1Institute of Surveying and Mapping , Information Engineering University ,Zhengzhou ,450052.Xi’an Research Institute of Surveying &Mapping , Xi’an,7100543Beijing Institute of Tracking and Communication technology , Beijing,1000974Xi’an Technical Division of Surveying &Mapping, Xi’an,710054)

The constellation of regional navigation satellite system are based on the mixed configuration, and the initial design doesn’t take the redundancy into account, so the system reliability is difficult to be guaranteed due to various satellite faulty factors. To ensure the constellation performance under the satellite failure conditions, the method on IGSO backup is studied and investigated in this paper. On the design constraints of only two surplus satellites, the IGSO orbit position and backup options are given through comparison and analysis. At the same time, from the view of meeting the global positioning satellite test and playing a backup role for IGSO, the orbital slots of four MEO of the basic constellation are adjusted and the on-orbit backup solution of 5GEO/5IGSO/4MEO is designed, which can effectively ensure the continuity and availability of system , and provide the reference for the optimization of system backup program.

关键词： on-orbit backup constellation value availability IGSO

The Application Study about Ground-Based GPS Precipitable Water Vapor in Shijiazhuang and Qinhuangdao Region

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The Application Study about Ground-Based GPS Precipitable Wa...

2.10 3rd IEEE International Conference on Computer Science and Information technology—ICCSIT 2.10

作者： Wang Yong 1 2.1.College of Traffic and Surveying Hebei Polytechnic University Tangshan china 2.Key laboratory of Mine Spatial Information Technologies (Henan Polytechnic University Henan Bureau of Surveying and Mapping) State Bureau of Surveying and Mapping Jiaozuo china Ding Keliang School of Surveying and Civil Spatial Information Beijing University of Civil Engineering and Architecture Beijing china He Rong School of Surveying and Land Infomation Engineering Henan Polytechnic University Jiaozuo china Liu Yanping College of Traffic and Surveying Hebei Polytechnic University Tangshan china

Water vapor is a highly variable parameter in atmospheric processes and it plays a crucial role in atmospheric motions on a wide range of scales in space and time. GPS technique has been widely used in retrieving precipitable water vapor. Firstly the article has retrieved precipitable water vapor of Qinhuangdao and Shijiazhuang stations by GPS technique. Then it has researched two aspects of precipitable water vapor. One is the spatial and temporal distribution characters of precipitable water vapor;the other is the relation between precipitable water vapor and actual rainfall. The value of GPS precipitable water vapor of Shijiazhuang is higher than the value of GPS precipitable water vapor of Qinhuangdao, which is accord to the formula that the precipitable water vapor is reduced from south to north. During the different time of a day, there are differ degree fluctuate which the min value present to morning and the max value present to evening. It also compared the GPS precipitable water vapor and actual rainfall. Although the time of max value about rainfall is not identical to the time of max value about precipitable water vapor, rainfall has occurred mostly in the time while the value of precpitable water vapor is high.

关键词： Global positioning system Precipitable water vapor Zenith tropospheric delay Zenith wet delay

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别矿台阶深孔爆破孔排距优化试验及应用

爆破 2018年第1期35卷 59-65页

作者：郭春阳池恩安赵明生欧阳天云汪帅文邹锐贵州新联爆破工程集团有限公司贵阳550025 贵州大学矿业学院贵阳550025 保利久联控股集团有限责任公司贵阳550025 武汉科技大学理学院武汉430065

别斯库都克露天煤矿剥采工程为探寻细砂岩地矿条件下12. mm孔径台阶深孔爆破合适的孔排距,寻求爆破效果与采装设备之间的匹配;在立足现有施工工艺、机械设备条件下,采用工程试验法调试最适孔排距。先后在+12.0、+12.4、+12.8平台... 详细信息

别斯库都克露天煤矿剥采工程为探寻细砂岩地矿条件下12. mm孔径台阶深孔爆破合适的孔排距,寻求爆破效果与采装设备之间的匹配;在立足现有施工工艺、机械设备条件下,采用工程试验法调试最适孔排距。先后在+12.0、+12.4、+12.8平台试用孔排距7 m×4 m、7 m×3.5 m、6.5 m×3.5 m,结合运输设备与车辆计数仪采用间接法统计采装效率、大块率,借助GPS空间定位、RTK测量、CASS7.0辅助绘图而计算爆挖方量;摸索出适合别矿细砂岩12. mm孔径台阶深孔孔排距为6.5 m×3.5 m。爆后采装效率达5.8车/h,大块率4.3%~4.4%,爆破单耗0.48 kg/m^3,爆挖率达97%~98%,一个双班期间产生特大块数为1,甚至无特大块,爆破综合效果最优。

关键词：孔排距采装设备爆破效果采装效率爆破单耗大块率爆挖率

Analyses of Anti-spoofing Threshold for GNSS Receivers

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Analyses of Anti-spoofing Threshold for GNSS Receivers

第三届中国卫星导航学术年会

作者： Long Huang1, Junwei Nie, Yuanling Li, Feixue Wang 1. Satellite navigation R&D Center, National Univ. of Defense technology, Changsha, {2.

Spoofing to satellite navigation receivers refers to the interference by re-radiating the authentic signals or generating similar spoofing signals, which can conduct effective interference with lower power than conventional interference technologies. Since the traditional satellite navigation systems like GPS and GLONASS didn’t consider the impact of spoofing, the only way to improve the anti-spoofing capabilities is to develop some anti-spoofing techniques in the GNSS receivers. This paper analyze the invade process of spoofing signals into the receiver code tracking loops, and conclude the relationship between the receiver anti-spoofing threshold and the loop bandwidth and the early-late {2. of the DLL. Analyze results shows that by optimizing the code tracking loop parameters, the receiver anti-spoofing threshold can be improved greatly. In the end, the conclusion above is tested and verified by software-receiver simulation.

关键词： GNSS satellite navigation receiver spoofing interference antispoofing threshold

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面向家居环境的双目视觉门识别方法

计算机集成制造系统 2018年第3期24卷 679-688页

作者：薛林王玉亮王巍林贺魏然北京航空航天大学机械工程及自动化学院北京100191 北京进化者机器人科技有限公司北京100192

为了提高家居环境下门识别的准确率和门定位的精度,提出一种基于双目视觉的门识别方法。该方法通过采用Scharr算子和霍夫变换算法提取双目传感器采集图像中的竖直线段,并利用特征直方图相似度进行竖线特征匹配。根据双目测距原理提出"... 详细信息

为了提高家居环境下门识别的准确率和门定位的精度,提出一种基于双目视觉的门识别方法。该方法通过采用Scharr算子和霍夫变换算法提取双目传感器采集图像中的竖直线段,并利用特征直方图相似度进行竖线特征匹配。根据双目测距原理提出"疑似门"的概念,提取了门的侧边框特征、深度突变特征、遮挡特征和颜色对称特征,利用特征积分制有效地解决了门的状态多变问题,实现了对家居环境下门的识别。实验结果表明,该方法对门的识别率可达93%,同时检测速度符合家庭服务机器人对实时性的要求。

关键词：竖线特征匹配门识别双目立体视觉家庭服务机器人