期刊文献+
共找到13篇文章
< 1 >
每页显示 20 50 100
The Design of I/O Subsystem in Satellite Real-Time Microkernel Operating System 被引量:1
1
作者 Liu Xiaodong & Li Lianzhi (Dept. of Computer Science & Engineering, Harbin Institute of Technology, 150001, P. R. China) Qian Chunlai(Beijiing Institute of Radio Measurement, 100854, P. R. China) 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1998年第3期77-81,共5页
One of the most important features of modern minor satellites is to realize autonomous moving. The performance of the satellite autonomous computer operating system acting as the control center is utmost important. Th... One of the most important features of modern minor satellites is to realize autonomous moving. The performance of the satellite autonomous computer operating system acting as the control center is utmost important. The recent trend in operating system development is adopting microkernel architecture which holds such advantages as microminiaturization, modularity, portability and extendibility. The performance of I/O subsystem is currently receiving considerable research attention. Object-orientation offers an approach to application development in which software system can be constructed by composing and refining the pre-designed plug-compatible software components.It also starts with some basic notions fairly well accepted in computer science, namely encapsulation and reuse. In this paper, a new object-oriented real-time I/O subsystem model has been designed.In this model, the traditional I/O subsystem framework is discarded and a stream mechanism based on the object-oriented concept is introduced. In addition, the I/O requests are classified according to their time emergency to obtain real-time performance. So, this model meets such satelliteperformance requirements as reliability, flexibility, portability and real-time performance. 展开更多
关键词 satellite operating system I/O subsystem OBJECT-ORIENTED REAL-TIME
下载PDF
Recent Progress of Earth Observation Satellites in China
2
作者 HUANG Shusong QI Wenping +3 位作者 ZHANG Shuai XIA Tian WANG Jingqiao ZENG Yong 《空间科学学报》 CAS CSCD 北大核心 2024年第4期731-740,共10页
Currently,China has 32 Earth observation satellites in orbit.The satellites can provide various data such as optical,multispectral,infrared,and radar.The spatial resolution of China Earth observation satellites ranges... Currently,China has 32 Earth observation satellites in orbit.The satellites can provide various data such as optical,multispectral,infrared,and radar.The spatial resolution of China Earth observation satellites ranges from low to medium to high.The satellites possess the capability to observe across multiple spectral bands,under all weather conditions,and at all times.The data of China Earth observation satellites has been widely used in fields such as natural resource detection,environmental monitoring and protection,disaster prevention and reduction,urban planning and mapping,agricultural and forestry surveys,land survey and geological prospecting,and ocean forecasting,achieving huge social benefits.This article introduces the recent progress of Earth observation satellites in China since 2022,especially the satellite operation,data archiving,data distribution and data coverage. 展开更多
关键词 China Earth Observation satellites satellite operation Data archiving Data distribution Data coverage
下载PDF
FY-3E:The First Operational Meteorological Satellite Mission in an Early Morning Orbit 被引量:19
3
作者 Peng ZHANG Xiuqing HU +5 位作者 Qifeng LU Aijun ZHU Manyun LIN Ling SUN Lin CHEN Na XU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2022年第1期1-8,共8页
Fengyun-3 E(FY-3E),the world’s first early-morning-orbit meteorological satellite for civil use,was launched successfully at the Jiuquan Satellite Launch Center on 5 July 2021.The FY-3E satellite will fill the vacanc... Fengyun-3 E(FY-3E),the world’s first early-morning-orbit meteorological satellite for civil use,was launched successfully at the Jiuquan Satellite Launch Center on 5 July 2021.The FY-3E satellite will fill the vacancy of the global early-morning-orbit satellite observation,working together with the FY-3C and FY-3D satellites to achieve the data coverage of early morning,morning,and afternoon orbits.The combination of these three satellites will provide global data coverage for numerical weather prediction(NWP)at 6-hour intervals,effectively improving the accuracy and time efficiency of global NWP,which is of great significance to perfect the global earth observing system.In this article,the background and meteorological requirements for the early-morning-orbit satellite are reviewed,and the specifications of the FY-3E satellite,as well as the characteristics of the onboard instrumentation for earth observations,are also introduced.In addition,the ground segment and the retrieved geophysical products are also presented.It is believed that the NWP communities will significantly benefit from an optimal temporal distribution of observations provided by the early morning,mid-morning,and afternoon satellite missions.Further benefits are expected in numerous applications such as the monitoring of severe weather/climate events,the development of improved sampling designs of the diurnal cycle for accurate climate data records,more efficient monitoring of air quality by thermal infrared remote sensing,and the quasicontinuous monitoring of the sun for space weather and climate. 展开更多
关键词 FY-3E operational meteorological satellite early morning orbit
下载PDF
Satellite remote sensing of sea-ice and its operational monitoring method along the coast of China 被引量:3
4
作者 Gong Jialong National Marine Environment Forecasting Center, SOA, Beijing. China 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1989年第3期379-390,共12页
Sea-ice is an important operational item for real timely monitoring and forecasting marine environment of China. This paper introduces an operational method of satellite remote sensing to monitor sea- ice using quanti... Sea-ice is an important operational item for real timely monitoring and forecasting marine environment of China. This paper introduces an operational method of satellite remote sensing to monitor sea- ice using quantitative data of NOAA, and its contents include computer processing of AVHRR sounding data of NOAA and its program design, imagery processing of sea-ice imagery from satellite and their thematic analysis. The sea-ice satellite colour imageries processed via this software system are able to interpret sea-ice pattern, characterizing it by thickness, maximum position of ice boundary, floe concentration and dynamic process of ice changing. At the same time, analyses of the ice condition of the Bohai Sea for the two-year period (1986-1988) as monitored by satellite have been summarized. 展开更多
关键词 In satellite remote sensing of sea-ice and its operational monitoring method along the coast of China
下载PDF
China's Operational Communications Satellite DFH-2A
5
作者 Liu Jierong Li Ye 《Aerospace China》 1995年第1期6-9,共4页
This paper describes the DFH-2A communications satellite which is the second generation of Chinese domestic communications satellites.From March 7,1988 to December 28,1991,China launched 4 DFH-2A satellites.They have ... This paper describes the DFH-2A communications satellite which is the second generation of Chinese domestic communications satellites.From March 7,1988 to December 28,1991,China launched 4 DFH-2A satellites.They have been used for CCTV’s and local TV’s programs transmission,domestic communications and broadcasting to foreign countries. 展开更多
关键词 DFH China’s Operational Communications satellite DFH-2A SSPA
下载PDF
GF-3 Satellite Put into Operation
6
作者 CUI Enhui 《Aerospace China》 2017年第1期61-61,共1页
GF-3,China’s first C-band Synthetic Aperture Radar(SAR)satellite with multiple polarizations,has been put into use from January 23.The SAR-C satellite has a 1 m resolution.CNSA Deputy Director WU Yanhua and CASC Vice... GF-3,China’s first C-band Synthetic Aperture Radar(SAR)satellite with multiple polarizations,has been put into use from January 23.The SAR-C satellite has a 1 m resolution.CNSA Deputy Director WU Yanhua and CASC Vice President YANG Baohua attended the ceremony for the commencement of formal operation of GF-3.GF-3 is the first LEO remote sens- 展开更多
关键词 CASC GF-3 satellite Put into Operation
下载PDF
Evolution Process of Urban Spatial Pattern in Hubei Province Based on DMSP/OLS Nighttime Light Data 被引量:4
7
作者 ZHENG Wensheng RUN Jiying +2 位作者 ZHUO Rongrong JIANG Yupei WANG Xiaofang 《Chinese Geographical Science》 SCIE CSCD 2016年第3期366-376,共11页
This paper intends to investigate the urban spatial patterns of Hubei Province and its evolution from three different perspectives: urban nodes, urban connections and urban clusters. The research adopts nighttime ligh... This paper intends to investigate the urban spatial patterns of Hubei Province and its evolution from three different perspectives: urban nodes, urban connections and urban clusters. The research adopts nighttime light imagery of cities in Hubei Province, the viewpoint of ′point-axis-area′ in the ′point-axis system′ theory, and employs light index model, gravity model and social network analysis. The findings are as follows: 1) In terms of urban nodes, the urbanization process of Hubei has been carried out mainly on the basis of external expansion rather than internal increasing. The polarization trend of urban connection network is strengthening. 2) As for urban connections, the estimation of urban connections using light index model is capable of containing various actual flow, and the connections are getting increasingly closer. 3) In regard to urban groups, seven urban groups of varying sizes have formed. On that basis, three stable and relatively independent urban groups as the centers, namely Wuchang, Yichang and Xiangyang emerge as well. But the structures of ′Wuhan Metropolitan Area′, ′Yichang-Jingzhou-Jingmen City Group′ and ′Xiangyang-Shiyen-Suizhou City Group′, which are defined by local development strategy in Hubei Province, are different from the above three urban groups. 展开更多
关键词 Defence Meteorological satellite Program′s Operational Linescan system(DMSP/OLS) urban spatial pattern point-axis-area Hubei Province China
下载PDF
Spatio-temporal Dynamics of Urbanization in China Using DMSP/OLS Nighttime Light Data from 1992–2013 被引量:1
8
作者 XU Pengfei LIN Muying JIN Pingbin 《Chinese Geographical Science》 SCIE CSCD 2021年第1期70-80,共11页
Understanding the dynamics of urbanization is essential to the sustainable development of cities. Meanwhile the analysis of urban development can also provide scientifically and effective information for decision-maki... Understanding the dynamics of urbanization is essential to the sustainable development of cities. Meanwhile the analysis of urban development can also provide scientifically and effective information for decision-making. With the long-term Defense Meteorological Satellite Program’s Operational Linescan System(DMSP/OLS) nighttime light images, a pixel level assessment of urbanization of China from 1992 to 2013 was conducted in this study, and the spatio-temporal dynamics and future trends of urban development were fully detected. The results showed that the urbanization and urban dynamics of China experienced drastic fluctuations from 1992 to 2013, especially for those in the coastal and metropolitan areas. From a regional perspective, it was found that the urban dynamics and increasing trends in North Coast China, East Coast China and South Coast China were much more stable and significant than that in other regions. Moreover, with the sustainability estimating of nighttime light dynamics, the regional agglomeration trends of urban regions were also detected. The light intensity in nearly 50% of lighted pixels may continuously decrease in the future, indicating a severe situation of urbanization within these regions. In this study, The results revealed in this study can provided a new insight in long time urbanization detecting and is thus beneficial to the better understanding of trends and dynamics of urban development. 展开更多
关键词 Defense Meteorological satellite Program’s Operational Linescan system(DMSP/OLS)nighttime light URBANIZATION pixel level detection spatio-temporal dynamics future trends
下载PDF
Dual-quaternion-based satellite pose estimation and control with event-triggered data transmission 被引量:2
9
作者 LI ChunHui ZOU HengGuang +2 位作者 SHI DaWei SONG JiLiang WANG JunZheng 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2023年第5期1214-1224,共11页
This paper proposes an event-triggered active disturbance rejection control framework to achieve the simultaneous position and attitude control of a satellite in proximity operations.Firstly,to facilitate the satellit... This paper proposes an event-triggered active disturbance rejection control framework to achieve the simultaneous position and attitude control of a satellite in proximity operations.Firstly,to facilitate the satellite motion description,we derive the relative kinematics and dynamics in terms of dual quaternions with the considerations of internal uncertainties and external disturbances.Then,two kinds of event-triggered mechanisms in the sensor/observer and controller/actuator channels are proposed to reduce the utilization of onboard communication resources and to improve control performance,respectively.The observation error and tracking error of both the attitude and orbit systems are theoretically proven to be asymptotically bounded.Finally,the simulation results show that the proposed method can achieve simultaneous position and attitude tracking between target and chaser satellites with satisfactory control performance and reduced communication rates. 展开更多
关键词 active disturbance rejection control framework event-triggered mechanisms estimate and control position and attitude satellite in proximity operations dual quaternions
原文传递
GOES-16 ABI Brightness Temperature Observations Capturing Vortex Rossby Wave Signals during Rapid Intensification of Hurricane Irma(2017)
10
作者 Yanyang HU Xiaolei ZOU 《Journal of Meteorological Research》 SCIE CSCD 2024年第4期768-783,共16页
Geostationary Operational Environmental Satellite-16(GOES-16) Advanced Baseline Imager(ABI) observations of brightness temperature(TB) are used to examine the temporal evolutions of convection-affected structures of H... Geostationary Operational Environmental Satellite-16(GOES-16) Advanced Baseline Imager(ABI) observations of brightness temperature(TB) are used to examine the temporal evolutions of convection-affected structures of Hurricane Irma(2017) during its rapid intensification(RI) period from 0600 to 1800 UTC 4 September 2017.The ABI observations reveal that both an elliptical eye and a spiral rainband that originated from Irma's eyewall obviously exhibit wavenumber-2 TB asymmetries.The elliptical eye underwent a counterclockwise rotation at a mean speed of a wavenumber-2 vortex Rossby edge wave from 0815 to 1005 UTC 4 September.In the following about 2 hours(1025–1255 UTC 4 September),an inner spiral rainband originated from the eyewall and propagated at a phase speed that approximates the vortex Rossby wave(VRW) phase speed calculated from the aircraft reconnaissance data.During the RI period of Irma,ABI TB observations show an on–off occurrence of low TB intrusions into the eye,accompanying a phase lock of eyewall TB asymmetries of wavenumbers 1 and 2 and an outward propagation of VRW-like inner spiral rainbands from the eyewall.The phase lock leads to an energy growth of Irma's eyewall asymmetries.Although the eye remained clear from 1415 to 1725 UTC 4 September,an inner spiral rainband that originated from a large convective area also had a VRW-like outward propagation,which is probably due to a vertical tilt of Irma.This study suggests a potential link between convection sensitive GOES imager observations and hurricane dynamics. 展开更多
关键词 Geostationary Operational Environmental satellite(GOES)imager brightness temperature(TB) HURRICANE vortex Rossby wave(VRW)
原文传递
Mathematical prototypes for collocating geostationary satellites 被引量:6
11
作者 LI HengNian GAO ZhaoZhao +3 位作者 LI JiSheng LI QuanJun XUE Dan LI DongLin 《Science China(Technological Sciences)》 SCIE EI CAS 2013年第5期1086-1092,共7页
Collocating geostationary satellites sharing the same position is much demanded for satellite operation recently,the separation strategies are adopted to safeguard the satellites collocated of leaving the relative dis... Collocating geostationary satellites sharing the same position is much demanded for satellite operation recently,the separation strategies are adopted to safeguard the satellites collocated of leaving the relative distance beyond collision with different sets of orbit parameters.This paper presents the mathematical prototypes which establish the allowable relative distance with uncertainty of orbital determination(OD),as well as the orbital element offset for each pair of collocated satellites,and puts forward algorithms to build such relationship to face the challenge of putting three satellites sharing the same position,the algorithms to allocate the longitude,eccentricity and inclination for each satellite are also given to ascertain that the mathematical prototypes are the guide specification to design collocation strategy for geostationary satellites. 展开更多
关键词 geostationary satellite (GEO) satellite operation satellite collocation separation strategies
原文传递
Calculating collision probability for long-term satellite encounters through the reachable domain method 被引量:4
12
作者 Changxuan Wen Dong Qiao 《Astrodynamics》 EI CSCD 2022年第2期141-159,共19页
ABSTRACT Satellite encounters during close operations,such as rendezvous,formation,and cluster flights,are typical long-term encounters.The collision probability in such an encounter is a primary safety concern.In thi... ABSTRACT Satellite encounters during close operations,such as rendezvous,formation,and cluster flights,are typical long-term encounters.The collision probability in such an encounter is a primary safety concern.In this study,a parametric method is proposed to compute the long-term collision probability for close satellite operations with initial state uncertainty.Random relative state errors resulting from system uncertainty lead to possible deviated trajectories with respect to the nominal one.To describe such a random event meaningfully,each deviated trajectory sample should be mapped to a unique and time-independent element in a random variable(RV)space.In this study,the RV space was identified as the transformed state space at a fixed initial time.The physical dimensions of both satellites were characterized by a combined hard-body sphere.Transforming the combined hard-body sphere into the RV space yielded a derived ellipsoid,which evolved over time and swept out a derived collision volume.The derived collision volume was solved using the reachable domain method.Finally,the collision probability was computed by integrating a probability density function over the derived collision volume.The results of the proposed method were compared with those of a nonparametric computation-intensive Monte Carlo method.The relative difference between the two results was found to be<0.6%,verifying the accuracy of the proposed method. 展开更多
关键词 close satellite operations uncertainty random variables collision volume long-term collision probability reachable domain
原文传递
基于夜光遥感的山东省城市时空格局演化分析 被引量:5
13
作者 丛康林 董超 +1 位作者 薄鑫宇 韩佳坤 《测绘地理信息》 CSCD 2021年第5期78-82,共5页
基于1993年、1998年、2003年、2008年、2013年由美国军事气象卫星计划/线性扫描系统(defense meteorological satellite program/operational linescan system,DMSP/OLS)获取的山东省夜间灯光数据,结合山东省社会经济统计数据,采用夜间... 基于1993年、1998年、2003年、2008年、2013年由美国军事气象卫星计划/线性扫描系统(defense meteorological satellite program/operational linescan system,DMSP/OLS)获取的山东省夜间灯光数据,结合山东省社会经济统计数据,采用夜间灯光强度、城市扩张速度和区域发展指数,从夜光辐射遥感数据的视角分析了山东省二十年的城市时空分布规律和扩展模式。研究结果表明了夜光数据与城市区域发展指数的强相关性,揭示了山东省城市时空格局的演化过程。 展开更多
关键词 夜光遥感 美国军事气象卫星计划/线性扫描系统(defense meteorological satellite program/operational linescansystem DMSP/OLS) 时空格局 城市化
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部