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The First Verification Test of Space-Ground Collaborative Intelligence via Cloud-Native Satellites
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作者 Wang Shangguang Zhang Qiyang +2 位作者 Xing Ruolin Qi Fei Xu Mengwei 《China Communications》 SCIE CSCD 2024年第4期208-217,共10页
Recent advancements in satellite technologies and the declining cost of access to space have led to the emergence of large satellite constellations in Low Earth Orbit(LEO).However,these constellations often rely on be... Recent advancements in satellite technologies and the declining cost of access to space have led to the emergence of large satellite constellations in Low Earth Orbit(LEO).However,these constellations often rely on bent-pipe architecture,resulting in high communication costs.Existing onboard inference architectures suffer from limitations in terms of low accuracy and inflexibility in the deployment and management of in-orbit applications.To address these challenges,we propose a cloud-native-based satellite design specifically tailored for Earth Observation tasks,enabling diverse computing paradigms.In this work,we present a case study of a satellite-ground collaborative inference system deployed in the Tiansuan constellation,demonstrating a remarkable 50%accuracy improvement and a substantial 90%data reduction.Our work sheds light on in-orbit energy,where in-orbit computing accounts for 17%of the total onboard energy consumption.Our approach represents a significant advancement of cloud-native satellite,aiming to enhance the accuracy of in-orbit computing while simultaneously reducing communication cost. 展开更多
关键词 cloud-native satellite orbital edge computing satellite inference verification test
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Recent Progress of Earth Observation Satellites in China
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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
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Geomorphic signatures and active tectonics in western Saurashtra,Gujarat,India
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作者 Bikramaditya Mondal Mery Biswas +1 位作者 Soumyajit Mukherjee Mohamedharoon A.Shaikh 《Geodesy and Geodynamics》 EI CSCD 2024年第1期82-99,共18页
Active tectonics in an area includes ongoing or recent geologic events.This paper investigates the tectonic influence on the subsidence,uplift and tilt of western Saurashtra through morphotectonic analysis of ten wate... Active tectonics in an area includes ongoing or recent geologic events.This paper investigates the tectonic influence on the subsidence,uplift and tilt of western Saurashtra through morphotectonic analysis of ten watersheds along with characteristics of relief and drainage orientation.Watersheds 7-9 to the north(N)are tectonically active,which can be linked with the North Kathiawar Fault System(NKFS)and followed by watersheds 6,10,1,4 and 5.Stream-length gradient index and sinuosity index indicate the effect of tectonic events along the master streams in watersheds 6-9.Higher R^(2)values of the linear curve fit for watershed 7 indicate its master stream is much more tectonically active than the others.The R^(2)curve fitting model and earthquake magnitude/depth analysis confirm the region to be active.The reactivation of the NKFS most likely led to the vertical movement of western Saurashtra. 展开更多
关键词 Active tectonics GEOMORPHOLOGY Western Saurashtra ARCHEOLOGY North kathiawar fault system
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Performance evaluation of HY-2 series satellites in marine gravity field recovery
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作者 Ruijie Hao Xiaoyun Wan Keyan Zhang 《Geodesy and Geodynamics》 EI CSCD 2024年第4期397-403,共7页
China has successfully launched four Haiyang-2(HY-2)series altimetry satellites.HY-2A has attracted significant attention in gravity field recovery,but the performance of other HY-2 series satellites,including HY-2B/C... China has successfully launched four Haiyang-2(HY-2)series altimetry satellites.HY-2A has attracted significant attention in gravity field recovery,but the performance of other HY-2 series satellites,including HY-2B/C/D,is seldom discussed.This study evaluated the performance of all the HY-2 series satellites in recovering marine gravity field.First,the crossover discrepancies in sea surface height of the four satellites,HY-2A,HY-2B,HY-2C,and HY-2D,were analyzed to assess their altimetry stability.It was found that HY-2B had the best altimetry quality,followed by HY-2D.Subsequently,different combina-tions of altimetry data were used to calculate vertical deflections and gravity anomalies in the South China Sea(112°E-119°E,12°N-20°N).The results showed that combining data from HY-2B,HY-2C,and HY-2D improved the inversion accuracy of gravity anomalies by 0.3 mGal compared to using HY-2A data alone.HY-2C and HY-2D contributed to enhancing the accuracy of the east component of vertical deflections. 展开更多
关键词 Satellite altimetry HY-2 Sea surfaceheight Marinegravityfield
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The Middle and Lower Cambrian salt tectonics in the central Tarim Basin,China:A case study based on strike-slip fault characterization
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作者 Qing Bian Jibiao Zhang Cheng Huang 《Energy Geoscience》 EI 2024年第2期53-61,共9页
Due to the considerable depth of the salt layers and the lack of calibration by exploratory drilling,the interpretation of the Middle and Lower Cambrian salt formations in the central Tarim Basin poses a challenge.In ... Due to the considerable depth of the salt layers and the lack of calibration by exploratory drilling,the interpretation of the Middle and Lower Cambrian salt formations in the central Tarim Basin poses a challenge.In this paper,we apply the coupling and decoupling deformation theory in salt tectonics to analyze the No.7 fault mapped in the seismic datasets by the response characteristics of the Middle and Lower Cambrian layers.By quantifying the stratigraphic framework of the Middle and Lower Cambrian strata,we define the position of the salt layer with the seismic data.Structural decoupling is observed in the Middle and Lower Cambrian sequences in the Shuntuoguole Low Uplift,while deformation coupling is observed in these two sequences in the Shaya Uplift. 展开更多
关键词 Tarim Basin Salt tectonics Strike-slip fault Structural analysis Seismic interpretation of decoupling zone
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Networking Observation and Applications of Chinese Ocean Satellites
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作者 ZOU Bin LIU Yuxin 《空间科学学报》 CAS CSCD 北大核心 2024年第4期722-730,共9页
This paper presents the networking observation capabilities of Chinese ocean satellites and their diverse applications in ocean disaster prevention,ecological monitoring,and resource development.Since the inaugural la... This paper presents the networking observation capabilities of Chinese ocean satellites and their diverse applications in ocean disaster prevention,ecological monitoring,and resource development.Since the inaugural launch in 2002,China has achieved substantial advancements in ocean satellite technology,forming an observation system composed of the HY-1,HY-2,and HY-3 series satellites.These satellites are integral to global ocean environmental monitoring due to their high resolution,extensive coverage,and frequent observations.Looking forward,China aims to further enhance and expand its ocean satellite capabilities through ongoing projects to support global environmental protection and sustainable development. 展开更多
关键词 Chinese ocean satellites Networking observation Ocean forecasting Ocean disaster prevention and mitigation Ocean ecological monitoring Ocean resource development Polar monitoring Terrestrial applications
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Development of Integrated and Intelligent Geodetic and Photogrammetry Satellites with Corresponding Key Technologies 被引量:2
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作者 Yuanxi YANG Xia REN Jianrong WANG 《Journal of Geodesy and Geoinformation Science》 CSCD 2023年第4期3-12,共10页
Aerospace surveying and mapping has become the main method of global earth observation.It can be divided into the geodetic observation satellites and the topographic surveying satellites according to the disciplines.I... Aerospace surveying and mapping has become the main method of global earth observation.It can be divided into the geodetic observation satellites and the topographic surveying satellites according to the disciplines.In this paper,the geodetic satellites and photographic satellites are introduced respectively.Then,the existing problems in Chinese earth observation satellites are analyzed,and the comprehensive satellite with integrated payloads,the intensive microsatellite constellation and the intelligent observation satellite are proposed as three different development ideas for the future earth observation satellites.The possibility of the three ideas is discussed in detail,as well as the related key technologies. 展开更多
关键词 aerospace surveying and mapping gravity satellite magnetic satellite optical mapping satellite microwave mapping satellite microsatellite networking intelligent satellite observation
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Evaluation of the Long-term Performance of Microwave Radiation Imager Onboard Chinese Fengyun Satellites 被引量:3
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作者 Wenying HE Hongbin CHEN +2 位作者 Xiang’ao XIA Shengli WU Peng ZHANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第7期1257-1268,共12页
Accurate brightness temperature(BT)is a top priority for retrievals of atmospheric and surface parameters.Microwave Radiation Imagers(MWRIs)on Chinese Fengyun-3(FY-3)serial polar-orbiting satellites have been providin... Accurate brightness temperature(BT)is a top priority for retrievals of atmospheric and surface parameters.Microwave Radiation Imagers(MWRIs)on Chinese Fengyun-3(FY-3)serial polar-orbiting satellites have been providing abundant BT data since 2008.Much work has been done to evaluate short-term MWRI observations,but the long-term performance of MWRIs remains unclear.In this study,operational MWRI BTs from 2012–19 were carefully examined by using simultaneous Advanced Microwave Scanning Radiometer 2(AMSR2)BTs as the reference.The BT difference between MWRI/FY3B and AMSR2 during 2012–19 increased gradually over time.As compared with MWRI/FY3B BTs over land,those of MWRI/FY3D were much closer to those of AMSR2.The ascending and descending orbit difference for MWRI/FY3D is also much smaller than that for MWRI/FY3B.These results suggested the improvement of MWRI/FY3D over MWRI/FY3B.A substantial BT difference between AMSR2 and MWRI was found over water,especially at the vertical polarization channels.A similar BT difference was found over polar water based on the simultaneous conical overpassing(SCO)method.Radiative transfer model simulations suggested that the substantial BT differences at the vertical polarization channels of MWRI and AMSR2 over water were partly contributed by their difference in the incident angle;however,the underestimation of the operational MWRI BT over water remained a very important issue.Preliminary assessment of the operational and recalibrated MWRI BT demonstrated that MWRI BTs were substantially improved after the recalibration,including the obvious underestimation of the operational MWRI BT at the vertical polarization channels over water was corrected,and the time-dependent biases were reduced. 展开更多
关键词 FY-3 satellites MWRI AMSR2 brightness temperature RECALIBRATION
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A Positioning Method and Realization on Single Satellites in Different Orbits Using TDOA 被引量:1
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作者 Laiding Zhao Xun Zhu +1 位作者 Gengxin Zhang Zhaowen Wang 《China Communications》 SCIE CSCD 2023年第7期108-121,共14页
The main geolocation technology currently used in COSPAS-SARSAT system is TDOA/FDOA or three-star TDOA,the principle is to determine the location of the signal source by using the difference in arrival time and freque... The main geolocation technology currently used in COSPAS-SARSAT system is TDOA/FDOA or three-star TDOA,the principle is to determine the location of the signal source by using the difference in arrival time and frequency of the wireless signal between different receivers.Therefore,ground monitoring stations need to be equipped with more than two antenna receiving stations,and multiple satellites should be able to simultaneously relay the distress signal from the target source in order to achieve the geolocation function.However,when the ground receiving system has only one antenna receiving station,or the target source is in a heavily obscured environment,the ground side is unable to receive the forwarded signals from multiple satellites at the same time,which will make it impossible to locate.To address these problems,in this paper,a time-sharing single satellite geolocations method based on different orbits is proposed for the first time.This method uses one or several low-earth orbit satellites(LEO)and mediumearth orbit satellites(MEO)in the visible area,and the receiving station only needs one pair of receiving antennas to complete the positioning.It can effectively compensate for the shortcomings of the traditional TDOA using the same moment and have better positioning accuracy compared with the single satellite in the same orbit.Due to the limited experimental conditions,this paper tests the navigation satellite using different orbit time-sharing single satellite geolocations,and proves that the positioning method has high positioning accuracy and has certain promotion and application value. 展开更多
关键词 different orbit time-sharing non-convex optimization single satellite TDOA
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Influence of Solar Activity on Precise Orbit Prediction of LEO Satellites
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作者 Jun-Jun Yuan Shan-Shi Zhou +4 位作者 Cheng-Pan Tang Bin Wu Kai Li Xiao-Gong Hu Er-Tao Liang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2023年第4期56-65,共10页
The perturbations of low earth orbit(LEO)satellites operating in the orbit of 300~2000 km are complicated.In particular,the atmospheric drag force and solar radiation pressure force change rapidly over a short period ... The perturbations of low earth orbit(LEO)satellites operating in the orbit of 300~2000 km are complicated.In particular,the atmospheric drag force and solar radiation pressure force change rapidly over a short period of time due to solar activities.Using spaceborne global positioning system(GPS)data of the CHAMP,GRACE and SWARM satellites from 2002 to 2020,this paper studies in depth the influence of solar activity on LEO satellites’precise orbit prediction by performing a series of orbit prediction experiments.The quality of GPS data is more susceptible to being influenced by solar activity during years when this activity is high and the changes in dynamic parameters are consistent with those of solar activity.The effects of solar activity on LEO orbit prediction accuracy are analyzed by comparing the predicted orbits with the precise ones.During years of high solar activity,the average root-mean-squares prediction errors at 10,20,and 30 minutes are 0.15,0.20,and 0.26 m,respectively,which are larger than the corresponding values in low-solar-activity years by 59%,63%,and 68%,respectively.These results demonstrate that solar activity has a great influence on the orbit prediction accuracy,especially during high-solar-activity years.We should strengthen the real-time monitoring of solar activity and geomagnetic activity,and formulate corresponding orbit prediction strategies for the active solar period. 展开更多
关键词 SUN activity-atmospheric effects-space vehicles instruments-planets and satellites atmospheres-planets and satellites dynamical evolution and stability-planets and satellites fundamental parameters
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Neoproterozoic(750–711 Ma)Tectonics of the South Qinling Belt,Central China:New Insights from Geochemical,Zircon U-Pb Geochronological,and Sr-Nd Isotopic Data from the Niushan Complex
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作者 WANG Shuo LIU Yunhua +3 位作者 YANG Benzhao TAN Le LI Xiaoyan DENG Nan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2023年第1期106-121,共16页
The Xiejiaba and Fuqiangbei plutons form part of the newly identified Neoproterozoic Niushan complex,which is located in the southern South Qinling belt(SQB).The plutons are compositionally similar,were emplaced at 75... The Xiejiaba and Fuqiangbei plutons form part of the newly identified Neoproterozoic Niushan complex,which is located in the southern South Qinling belt(SQB).The plutons are compositionally similar,were emplaced at 750–711Ma,and provide insights into Neoproterozoic tectonism within the South Qinling belt.The Xiejiaba pluton contains diorite,quartz diorite,granodiorite,and granite phases,all of which are sub-alkaline and have variable major element compositions with negative correlations between SiO_(2)and MgO,TFe_(2)O_(3),Al_(2)O_(3),CaO,TiO_(2)and P_(2)O_(5).These rocks are enriched in light rare earth elements(LREEs)and large ion lithophile elements(LILEs)and have negative Nb,Ta,P and Ti anomalies,all of which are indicative of arc-type magmatism.The Fuqiangbei pluton contains granitoids that are compositionally similar to the rocks in the Xiejiaba pluton.Samples from these plutons have similarε_(Nd)(t)values(1.24–5.99)but very variable(^(87)Sr/^(86)Sr)i values(0.7010–0.7054).Combining these data with the geochemical data for these rocks suggests that the magmas that formed the Niushan complex were derived from the crust–mantle boundary.This,combined with the results of previous research,suggests that the transition from low pressure-low temperature to low pressure-high temperature conditions within a subduction zone caused melting during a period of late subduction and backarc extension.This constrain the timing of subduction within the South Qinling belt and the northern Yangtze Block(YB)to 750–711 Ma,with this Neoproterozoic subduction associated with an ocean to the north overprinting an existing continental rift-type tectonic setting within the northern margin of the Yangtze Block and the South Qinling belt. 展开更多
关键词 geochronology geochemistry magmatism tectonics PRECAMBRIAN South Qinling
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Diagenesis of the Paleogene Sandstones in the DN2 Gas Field,Kuqa Foreland Basin and its Link to Tectonics
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作者 YU Guoding YUAN Jing +4 位作者 LIU Keyu YANG Xianzhang DONG Daotao MA Pengjie HUANG Chiqiang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2023年第5期1538-1554,共17页
We investigated diagenesis of the sandstones from the DN2 Gas Field of the Kuqa Foreland Basin(KFB),in order to infer the timing of fluid migration and discuss the linkage between fluids and tectonics.The textures and... We investigated diagenesis of the sandstones from the DN2 Gas Field of the Kuqa Foreland Basin(KFB),in order to infer the timing of fluid migration and discuss the linkage between fluids and tectonics.The textures and chemical composition of authigenic minerals,fluid evidence from fluid inclusions and formation water measurements were all used to fulfill this aim.Eodiagenesis occurred with the participation of meteoric water and connate water.Mesodiagenesis is related to high salinity fluids,which were attributed as originating from the overlying Neogene Jidike Formation evaporite(principal minerals including halite,anhydrite,glauberite,carnallite and thenardite).The onset of high salinity fluid migration is inferred to occur during the late Miocene(12.4-9.2 Ma)through the use of homogenization temperatures measured in the present study and K-Ar dating of authigenetic illites from previous work.This period is consistent with the crucial phase(13-10 Ma)that witnessed the rapid uplift of the southern Tianshan Mts and the stage when calcite and anhydrite veins formed in the studied strata.We thus argue that diagenesis related to high salinity fluids occurred as a response to the Tianshan Mts'rapid uplift and related tectonic processes.The flow of high salinity fluids was probably driven by a density gradient and channeled and focused by fractures formed contemporaneously. 展开更多
关键词 DIAGENESIS high salinity fluids meteoric waters tectonics Kuqa Foreland Basin Tianshan Mts
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Tectonics of the Solomon Sea Basin from Vertical Gravity Gradient and Seismic Data
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作者 GONG Wei XING Junhui +3 位作者 MENG Qingwei XING Lei XU Chong ZHANG Hao 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2023年第2期610-622,共13页
The Solomon Sea Basin is a Cenozoic back-arc spreading basin within the convergence system of the Pacific and Indo-Australian plates.Against the background of subduction polarity reversal,the current Solomon Sea Basin... The Solomon Sea Basin is a Cenozoic back-arc spreading basin within the convergence system of the Pacific and Indo-Australian plates.Against the background of subduction polarity reversal,the current Solomon Sea Basin gradually formed a rhombic morphology with the subduction of the basin along the New Britain Trench and the Trobriand Trough.By analyzing the vertical gravity gradient,natural earthquake and seismic reflection data,this study determines the structural characteristics of the Solomon Sea Basin.It was found that the tectonics of the basin are characterized by the original expansion structure within the central part in addition to the structure induced by the latest subduction along the basin margin.The original spreading structure of the basin presented an east–west linear graben and horst controlled by normal faults during the basin expansion period.As a result of the subduction and slab-pull of the Solomon Sea Basin,extensional structure belts parallel to the New Britain Trench formed along the basin margin. 展开更多
关键词 vertical gravity gradient seismic data tectonics New Britain Trench Solomon Sea Basin
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矿田构造岩相学填图理论及应用 被引量:1
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作者 方维萱 郭玉乾 +2 位作者 李天成 贾润幸 马振飞 《地质力学学报》 CSCD 北大核心 2024年第1期88-106,共19页
开展成矿蚀变−构造岩相解析建相和建模预测研究已成为矿田构造与找矿预测的创新方向之一。文章对国内外8类重要的成矿蚀变−构造岩相模型和形成机制进行论述总结,南美洲智利科皮亚波地区IOCG型矿田受到主岛弧带−弧相关盆地及岩浆叠加−盆... 开展成矿蚀变−构造岩相解析建相和建模预测研究已成为矿田构造与找矿预测的创新方向之一。文章对国内外8类重要的成矿蚀变−构造岩相模型和形成机制进行论述总结,南美洲智利科皮亚波地区IOCG型矿田受到主岛弧带−弧相关盆地及岩浆叠加−盆地变形样式的复合控制,而中国云南东川沉积岩型铜矿床(SSC型)+IOCG型铁铜矿田受陆缘裂谷盆地、盆地变形构造样式和岩浆叠加侵入构造系统的复合控制。中国内蒙古甲−查浅成低温热液型银铅锌矿田受火山洼地、火山穹隆构造、火山岩岩相类型和火山热液隐爆角砾岩的复合控制,而深成岩浆弧控制了蒙古国南戈壁斑岩型金铜钼−浅成低温热液金银矿田;中国秦岭热水沉积型(SEDEX)银铜铅锌−菱铁矿−重晶石矿田受到陆缘拉分盆地内三级热水沉积盆地、同生断裂带和热水沉积岩相的控制。大陆造山带内不同层次的脆韧性剪切带,控制了金矿田和金钼多金属矿田定位。在新疆塔西盆−山−原镶嵌区盆地系统内,侏罗系煤系烃矿源岩是金属矿田和天然气气田的成矿成藏物质供给源区;乌拉根砂砾岩型天青石−铅锌矿田受到山前挤压—伸展转换盆地、气成热流柱构造和山前冲断褶皱带的复合控制;萨热克铜多金属矿田赋存于旱地扇杂砾岩,受到对冲式厚皮型逆冲推覆断裂带和幔源热流柱带的复合控制。其中在矿集区−矿田尺度上,电气石热流柱构造、岩浆气囊构造、复合岩溶构造岩相等是成矿蚀变−构造岩相的3种新类型;在归纳前期对矿田构造岩相、矿田构造古地理单元和典型矿田构造岩相形成机制研究基础上,文章提出了矿田成矿蚀变−构造岩相类型的新划分方法和划分原则方案,并划分确定了12种变形构造岩相类型。研究成果为矿田构造研究和找矿预测提供了新理论和新方法支撑。 展开更多
关键词 矿田构造 矿田岩相学 成矿蚀变−构造岩相 成矿系统 构造岩相模型 形成机制
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Spacecraft potential variations of the Swarm satellites at low Earth orbital altitudes
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作者 HaiCheng Jiang Chao Xiong +4 位作者 Fan Yin YuHao Zheng ZiYuan Zhu Rui Yan Yi Wen Liu 《Earth and Planetary Physics》 CAS CSCD 2023年第4期421-435,共15页
In this study, we provide the first detailed analysis of variations in the spacecraft potential (Vs) of the three Swarm satellites, which are flying at about 400-500 km. Unlike previous studies that have investigated ... In this study, we provide the first detailed analysis of variations in the spacecraft potential (Vs) of the three Swarm satellites, which are flying at about 400-500 km. Unlike previous studies that have investigated extreme charging events, usually with spacecraft potentials as negative as −100 V, this study is focused on variations of Swarm Vs readings, which fall within a few negative volts. The Swarm observations show that spacecraft at low Earth orbital (LEO) altitudes are charged only slightly negatively, varying between −7 V and 0 V, with the majority of recorded potentials at these altitudes clustering close to −2 V. However, a second peak of Vs data is found at −5.5 V, though the event numbers for these more-negative observations are less, by an order of magnitude, than for incidents near the −2 V peak. These two distinct Vs peaks suggest two different causes. We have thus divided the Swarm spacecraft Vs data into two categories: less-negatively charged (−5 < Vs < 0 V) and more-negatively-charged (−6.5 < Vs < −5 V). These two Vs categories exhibit different spatial and temporal distributions. The Vs observations in the first category remain relatively closer to 0 V above the magnetic equator, but become much more negative at low and middle latitudes on the day side;at high latitudes, these first-category Vs readings are relatively more-negative during local summer. Second-category Vs events cluster into two bands at the middle latitudes (between ±20°-50° magnetic latitude), but with slightly more negative readings at the South Atlantic Anomaly (SAA) region;at high latitudes, these rarer but more-negative second-category Vs events exhibit relatively more-negative values during local winter, which is opposite to the seasonal pattern seen in the first category. By comparing Vs data to the distributions of background plasma density at Swarm altitudes, we find for the first category that more-negative Vs readings are recorded at regions with higher background plasma density, while for the second category the more-negative Vs data are observed at regions with lower background plasma density. This can be explained as follows: the electron and ion fluxes incident on Swarm surface, whose differences determine the potential of Swarm, are dominated by the background “cold” plasma (due to ionization) and “hot” plasma (due to precipitated particles from magnetosphere) for the two Vs categories, respectively. 展开更多
关键词 spacecraft potentia low Earth orbit satellites Swarm mission particle precipitation
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Simulation for MSS-2 low-perigee elliptical orbit satellites:an example of lithospheric magnetic field modelling
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作者 Yi Jiang Nils Olsen +1 位作者 JiaMing Ou Qing Yan 《Earth and Planetary Physics》 EI CSCD 2023年第1期151-160,共10页
A future constellation of at least four geomagnetic satellites(designated Macao Scientific Satellite-1(MSS-1)and Macao Scientific Satellite-2(MSS-2))was recently proposed,to continue high-quality geomagnetic observati... A future constellation of at least four geomagnetic satellites(designated Macao Scientific Satellite-1(MSS-1)and Macao Scientific Satellite-2(MSS-2))was recently proposed,to continue high-quality geomagnetic observations in the post-Swarm period,focusing especially on collecting data that will provide a global,three-dimensional survey of the geomagnetic field.In this paper,we present a simulation of two years of orbits(2020.01.01-2022.01.01)of two satellites(tentatively denoted as MSS-2)that are constellated in elliptical(200×5,300 km)low-perigee orbits.By comparing error variances of Gauss coefficients,we investigate the sensitivity of lithospheric magnetic field modelling to data collected from various satellite orbits,including a near circular reference orbit of 300×350km,and elliptical orbit of 180×5,300 km,220×5,300 km,200×3,000 km and 200×1,500 km.We find that in two years the two MSS-2 satellites can collect 35,000 observations at altitude below 250 km,data that will be useful in advancing the quality of lithospheric magnetic field modelling;this number of observations reflects the fact that only 4.5%of the flight time of these satellites will be below250 km(just 6.4%of their flight time below 300 km).By combining observations from the MSS-2 satellites’elliptical orbits of 200×5,300km with observations from a circular reference orbit,the variance of the geomagnetic model can be reduced by a factor of 285 at spherical harmonic degree n=200 and by a factor of 1,300 at n=250.The planned lower perigee of their orbits allows the new satellites to collect data at unprecedentedly lower altitudes,thus dramatically improving the spatial resolution of satellite-derived lithospheric field models,(up to 80%at n=150).In addition,lowering the apogee increases the time interval during which the satellites fly at near-Earth altitudes,thus improving the model predictions at all spherical harmonic degrees(around 52%-62%at n=150).The upper limit of the expected improvement to the field model at the orbital apogee is not as good as at the perigee.However,data from the MSS-1 orbit can help fill the gap between data from the MSS-2 orbits and from the circular reference orbit for the low-degree part of the model.The feasibility of even lower-altitude flight requires further discussion with satellite engineers. 展开更多
关键词 elliptical orbit satellite orbit simulation lithosphere field modelling spherical harmonics
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Evaluation of the Global Horizontal Irradiation (GHI) on the Ground from the Images of the Second Generation European Meteorological Satellites MSG
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作者 Ahmed El Ouiqary El M’kaddem Kheddioui Mohammed Faouzi Smiej 《Journal of Computer and Communications》 2023年第1期1-11,共11页
The measurement of solar irradiation is still a necessary basis for planning the installation of photovoltaic parks and concentrating solar power systems. The meteorological stations for the measurement of the solar f... The measurement of solar irradiation is still a necessary basis for planning the installation of photovoltaic parks and concentrating solar power systems. The meteorological stations for the measurement of the solar flux at any point of the earth’s surface are still insufficient worldwide;moreover, these measurements on the ground are expensive, and rare. To overcome this shortcoming, the exploitation of images from the European meteorological satellites of the second generation MSG is a reliable solution to estimate the global horizontal irradiance GHI on the ground with a good spatial and temporal coverage. Since 2004, the new generation MSG satellites provide images of Africa and Europe every 15 minutes with a spatial resolution of about 1 km × 1 km at the sub-satellite point. The objective of this work was to apply the Brazil-SR method to evaluate the global horizontal GHI irradiance for the entire Moroccan national territory from the European Meteosat Second Generation MSG satellite images. This bibliographic review also exposed the standard model of calculation of GHI in clear sky by exploiting the terrestrial meteorological measurements. 展开更多
关键词 Global Horizontal Irradiation GHI MSG Satellite Images Brazil-SR Method
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A Large-Scale Scheduling Method for Multiple Agile Optical Satellites
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作者 Zheng Liu Wei Xiong Minghui Xiong 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第8期1143-1163,共21页
This study investigates the scheduling problem ofmultiple agile optical satelliteswith large-scale tasks.This problem is difficult to solve owing to the time-dependent characteristic of agile optical satellites,comple... This study investigates the scheduling problem ofmultiple agile optical satelliteswith large-scale tasks.This problem is difficult to solve owing to the time-dependent characteristic of agile optical satellites,complex constraints,and considerable solution space.To solve the problem,we propose a scheduling method based on an improved sine and cosine algorithm and a task merging approach.We first establish a scheduling model with task merging constraints and observation action constraints to describe the problem.Then,an improved sine and cosine algorithm is proposed to search for the optimal solution with the maximum profit ratio.An adaptive cosine factor and an adaptive greedy factor are adopted to improve the algorithm.Besides,a taskmerging method with a task reallocation mechanism is developed to improve the scheduling efficiency.Experimental results demonstrate the superiority of the proposed algorithm over the comparison algorithms. 展开更多
关键词 Multiple agile optical satellites scheduling task merging sine and cosine algorithm task reallocation
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塔里木盆地先巴扎地区走滑断裂特征及石油地质意义 被引量:2
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作者 马海陇 蒋林 +3 位作者 姜应兵 王震 郝建龙 王明 《断块油气田》 CAS CSCD 北大核心 2024年第2期266-275,共10页
文中利用三维地震资料开展了麦盖提斜坡先巴扎地区断裂的精细解析,明确了走滑断裂特征、形成期次、成因机制等,结合邻区含油气地质条件,探讨了奥陶系走滑断裂的含油气性,预测油气富集模式。研究发现,研究区发育北东向、北西向、近南北... 文中利用三维地震资料开展了麦盖提斜坡先巴扎地区断裂的精细解析,明确了走滑断裂特征、形成期次、成因机制等,结合邻区含油气地质条件,探讨了奥陶系走滑断裂的含油气性,预测油气富集模式。研究发现,研究区发育北东向、北西向、近南北向、北东东向等4组走滑断裂体系,主要经历了5期构造活动,形成了5个构造层:加里东早期发育北东向、北西向正断裂(基底构造层);加里东中晚期受西昆仑造山运动影响,部分正断裂继承活动,形成左行左阶北东向、右行左阶北西向走滑断裂(下构造层);加里东晚期—海西早期受阿尔金造山运动影响,形成1条左行左阶北东东向走滑断裂(中构造层);海西晚期北东向、北西向走滑断裂继承活动,同时新形成色力布亚逆冲断裂的近南北向伴生断裂(上构造层);喜山早期沿古近系膏泥层发育叠瓦状逆冲断裂及在喜山晚期发生整体掀斜(顶构造层)。基于邻区含油气特征,认为该区沿断裂带发育加里东中期Ⅰ—Ⅲ幕岩溶缝洞型储层,与上覆志留系泥岩形成储盖组合,海西晚期来自麦盖提斜坡西北部寒武系玉尔吐斯组的远源油气沿先巴扎断裂带向走滑断裂调整聚集成藏。其中,断穿基底的奥陶系北东向张扭走滑断裂的储集性能优于其他走向断裂,含油气条件最优越,值得探索。 展开更多
关键词 碳酸盐岩 走滑断裂 构造演化 先巴扎 塔里木盆地
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手机直连低轨卫星的应用场景及业务需求分析 被引量:1
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作者 刘悦 田野 +4 位作者 赵冬 李彦坤 杨虎啸 高然 忻向军 《电信科学》 北大核心 2024年第4期56-65,共10页
手机直连卫星是低轨(low earth orbiting,LEO)星座系统的重要应用方向之一。概述了手机直连卫星的主要技术路线、应用场景及业务类型;分析了低轨星座的建设成本、承载能力、运营收入;提出了我国手机直连卫星通信的主要应用应以广覆盖、... 手机直连卫星是低轨(low earth orbiting,LEO)星座系统的重要应用方向之一。概述了手机直连卫星的主要技术路线、应用场景及业务类型;分析了低轨星座的建设成本、承载能力、运营收入;提出了我国手机直连卫星通信的主要应用应以广覆盖、海量连接为主,而卫星大流量宽带上网应用存在商业闭环的风险;最后探讨了结合应用需求的技术发展建议。 展开更多
关键词 手机直连卫星 低轨星座系统 低空经济 非地面网络
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