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卫星数传分系统通用地检测试中频接收机设计

空间科学学报 2018年第1期38卷 109-117页

作者：高翔姚秀娟闫毅范亚楠王春梅中国科学院大学北京100049 中国科学院国家空间科学中心北京100190

为满足卫星数传分系统测试任务需求,提出一种通用性、灵活性强的地检测试中频接收机设计方案.采用软件无线电设计思想,设计基于PXIe总线的模块化平台,通过FPGA进行硬件实现,符合CCSDS标准.经过工程实践,所提出的地检测试中频接收机方案... 详细信息

为满足卫星数传分系统测试任务需求,提出一种通用性、灵活性强的地检测试中频接收机设计方案.采用软件无线电设计思想,设计基于PXIe总线的模块化平台,通过FPGA进行硬件实现,符合CCSDS标准.经过工程实践,所提出的地检测试中频接收机方案已应用于工程型号,并成功执行各阶段测试工作.

关键词：卫星数传 CCSDS 软件无线电 FPGA PXIe 综合基带平台

china space Environment Development

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空间科学学报 2008年第5期28卷 496-498页

作者： XU Ying wang shijin ZHU Guangwu LIANG Jinbao SUN Yueqiang center for space {2. and applied research Chinese Academy of Sciences Beijing 100190

This paper presents chinese space environment detection and parts of results,and gives a short perspective of space environment observations on chinese future satellites.

关键词：中国空间环境研究进展空间计划

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沙尘暴天气下云的飞机观测研究

应用气象学报 2024年第3期35卷 323-336页

作者：马新成毕凯王飞高洋黄梦宇北京市人工影响天气中心北京100089 云降水物理研究和云水资源开发北京市重点实验室北京100089 中国气象局华北云降水野外科学试验基地北京101200 国家卫星气象中心/国家空间天气监测预警中心北京100081

沙尘暴天气下云的飞机观测极其缺乏,为了研究亚洲中蒙地区沙尘气溶胶对云的影响,利用北京地区云的综合外场观测试验数据,分析2.09年4月2.日由蒙古气旋和冷锋造成的强沙尘暴天气下云的观测个例,对比分析沙尘云和清洁云垂直观测。结果表明... 详细信息

沙尘暴天气下云的飞机观测极其缺乏,为了研究亚洲中蒙地区沙尘气溶胶对云的影响,利用北京地区云的综合外场观测试验数据,分析2.09年4月2.日由蒙古气旋和冷锋造成的强沙尘暴天气下云的观测个例,对比分析沙尘云和清洁云垂直观测。结果表明:从亚洲中蒙地区输送的沙尘气溶胶是华北区域重要的冰核来源,可被垂直输送至云顶以上32.0 m高度,并通过改变冰晶形成过程影响云顶温度(-6~-3℃)较高的积云性层积云微物理结构。在相同温度下,沙尘云中冰晶平均数浓度较清洁云增加近10倍,液态水含量减少约1倍,云中形成大量小冰晶粒子,凇附过程受到抑制,降水粒子平均数浓度较清洁云中明显减少10倍以上,无论云滴、冰雪晶还是降水粒子谱宽均较清洁云明显变窄,并最终减弱降水,对华北区域的天气和气候产生重要影响。

关键词：沙尘气溶胶飞机观测层积云沙尘暴蒙古气旋

Reconciled estimation of Antarctic ice sheet mass balance and contribution to global sea level change from 1996 to 2.2.

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science china Earth {2. 2024年第11期67卷 3562-3578页

作者： Rongxing LI Guojun LI Gang HAI Huan XIE Yuan CHENG Wei CHEN Xiangbin CUI Minghu DING Chunchun GAO Tong HAO Changqing KE Chuanjin LI Jin LI Yan LIU Jiangjun RAN Jiawen REN Qiang SHEN Yunzhong SHEN Hongling SHI Songyun wang Zemin wang Jingang ZHAN Baojun ZHANG Min ZHONG Chunxia ZHOU center for Spatial Information science and Sustainable Development Applications Tongji University College of Surveying and Geo-informatics Tongji University Institute for the Conservation of Cultural Heritage School of Cultural Heritage and Information Management Shanghai University College of Resource Environment and Tourism Hubei University of Arts and Science Polar research Institute of china State Key Laboratory of Severe Weather Chinese Academy of Meteorological Sciences College of Geodesy and Geomatics Shandong University of Science and Technology School of Geography and Ocean science Nanjing University Shanghai Astronomical Observatory Chinese Academy of Sciences State Key Laboratory of Remote Sensing science Faculty of Geographical Science Beijing Normal University Department of Earth and space sciences Southern University of Science and Technology State Key Laboratory of Cryospheric science Northwest Institute of Eco-Environment and Resources Chinese Academy of Sciences State Key Laboratory of Geodesy and Earth's Dynamics Innovation Academy for Precision Measurement Science and TechnologyChinese Academy of Sciences center for space {2. University of Texas at Austin chinese Antarctic center of Surveying and Mapping Wuhan University School of Geospatial Engineering and science Sun Yat-sen University

The Antarctic Ice Sheet（AIS） has been losing ice mass and contributing to global sea level rise（GSLR）. Given its mass that is enough to cause ～58 m of GSLR, accurate estimation of mass balance trend is critical for AIS mass loss monitoring and sea level rise forecasting. Here, we present an improved approach to reconciled solutions of mass balance in AIS and its regions from multiple contributing solutions using the input-out, altimetric, and gravimetric methods. In comparison to previous methods, such as IMBIE 2.18, this approach utilizes an adaptive data aggregation window to handle the heterogeneity of the contributing solutions, including the number of solutions, temporal distributions, uncertainties, and estimation techniques. We improved the regression-based method by using a two-step procedure that establishes ensembled solutions within each method（input-output, altimetry, or gravimetry） and then estimates the method-independent reconciled solutions. For the first time, 16contributing solutions from 8 chinese institutions are used to estimate the reconciled mass balance of AIS and its regions from1996 to 2.2.. Our results show that AIS has lost a total ice mass of ～32.3±2.3 Gt during the period, an equivalent of～8.9±0.7 mm of GSLR. There is a sustained mass loss acceleration since 2.06, from 88.1±3.6 Gt yr-1during 1996–2.05 to 130.7 ±8.4 Gt yr-1during 2.06–2.13 and further to 157.0±9.0 Gt yr-1during 2.14–2.2.. The mass loss signal in the West Antarctica and Antarctic Peninsula is dominant and clearly presented in the reconciled estimation and contributing solutions, regardless of estimation methods used and fluctuation of surface mass balance. Uncertainty and challenges remain in mass balance estimation in East Antarctica. This reconciled estimation approach can be extended and applied for improved mass balance estimation in the Greenland Ice Sheet and mountain glacier regions.

关键词： Antarctic Ice Sheet Ice mass loss acceleration Sea level rise Reconciled estimation

Mineral Prospectivity Prediction via Convolutional Neural Networks Based on Geological Big Data

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Journal of Earth science 2021年第2期32卷 327-347页

作者： Shi Li Jianping Chen Chang Liu yang wang School of Earth sciences and Resources China University of GeosciencesBeijing 100083China Land Resources Information Development and research Key Laboratory of beijing Beijing 100083China Haikou Marine Geological Survey center China Geological SurveyHaikou 570100China

Today’s era of big data is witnessing a gradual increase in the amount of data,more correlations between data,as well as growth in their spatial *** linear statistical models applied to mineral prospectivity mapping(MPM)perform poorly because of the random and nonlinear nature of metallogenic *** overcome this performance degradation,deep learning models have been introduced in 3 D *** this study,taking the Huayuan sedimentary Mn deposit in Hunan Province as an example,we construct a 3 D digital model of this deposit based on the prospectivity model of the study *** this approach,3 D predictor layers are converted from the conceptual model and employed in a 3 D convolutional neural network(3 D CNN).The characteristics of the spatial distribution are extracted by the 3 D ***,we divide the 2. extracted ore-controlling variables into six groups for contrast experiments based on various combinations and further apply the 3 D CNN model and weight of evidence(WofE)method on each *** predictive model is trained on the basis of the coupling correlation between the spatial distributions of the variables and the underground occurrence space of the Mn orebodies,and the correlation between different ore-controlling *** analysis of 12.factors indicates that the 3 D CNN model performs well in the 3 D MPM,achieving a promising accuracy of up to 100%and a loss value below 0.001.A comparison shows that the 3 D CNN model outperforms the WofE model in terms of predictive evaluation indexes,namely the success rate and ore-controlling *** particular,the 1–12.ore-controlling factors selected in experiment 5 provide a significantly better prediction effect than the other ***,we conclude that the Mn deposit in the study area is not only related to the stratum and interlaminar anomalous bodies but also to the spatial distribution of the *** experimental results confirm that the proposed 3 D CNN is prom

关键词： big data mineral prospectivity mapping 3D geological modeling 3D CNN Huayuan Mn deposit

Statistical analysis of one chinese sun-synchronous satellite anomalies

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science china(Technological {2.) 2016年第4期59卷 540-546页

作者： TIAN Tian ZONG QiuGang CHANG Zheng wang YongFu yang XiaoHua Institute of space Physics and applied Technology Peking UniversityBeijing 100871China Mailbox 5111 Beijing 100094China center for space {2. and applied research Chinese Academy of SciencesBeijing 100190China

Based on the data from the Medium-Energy Proton and Electron Detector （MEPED） onboard NOAA-17, 141 anomalies of a chinese Sun-Synchronous satellite （SSO-X） that occurred between 02.01/2.10 and 09/31/2.12.were studied statistically. About 2. out of the 52.anomalies that occurred outside the South Atlantic Anomaly （SAA） were accompanied by energetic electron storms. Superposed Epoch Analysis （SEA） was used to analyze the properties of the anomalies and the dynamics of the space environments during these 2. events. Then, a Monte Carlo method was utilized to simulate the electron deposition and the interactions of the injected electrons with an aluminum shield and polyethylene dielectric. The average, median, and 75tb percentile values of the maximum electric field strength inside the dielectric were calculated. The results showed the tbl- lowing. （1） SSO-X anomalies are more likely to occur within the SAA, as 89 out of 141 anomalies （63%） occurred there. （2. Twenty-six of the anomalies that occurred outside the SAA during energetic electron storms were located near the outer boundaries of the outer radiation belts, and these were more frequent in the Southern Hemisphere than in the Northern Hemi- sphere. （3） Electron flux enhancements occurred around the failure time at all energy levels but were more profound in the lower energy channels. The maximum fluxes of electrons 〉30 keV, 〉100 keV, and 〉300 keV were 106, 3.5x10s, and 1.2.10^6 cm 2.s^-1 · sr ^-1, respectively. （4） The average, median, and 75th percentile values of the maximum electric field strengths inside the dielectric for the aforementioned 2. events remained in the range from 106 to 107 V/m for long time periods, which sug- gests that the ＇potential hazards＇ of internal discharges cause SSO-X anomalies. The above results can provide useful infor- mation for the design and protection of sun-synchronous spacecraft.

关键词： SSO-X failure superposed epoch analysis Monte Carlo method internal charging maximum electric field strength radiation belts

Structural transition,electric transport,and electronic structures in the compressed trilayer nickelate La_(4)Ni_(3)O_(10)

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science china(Physics,Mechanics & Astronomy) 2024年第11期67卷 9-15页

作者： Jingyuan Li Cui-Qun Chen Chaoxin Huang Yifeng Han Mengwu Huo Xing Huang Peiyue Ma Zhengyang Qiu Junfeng Chen Xunwu Hu Lan Chen Tao Xie Bing Shen Hualei Sun Dao-Xin Yao Meng wang center for Neutron science and Technology Guangdong Provincial Key Laboratory of Magnetoelectric Physics and DevicesSchool of PhysicsSun Yat-sen UniversityGuangzhou 510275China center for Materials of the Universe School of Molecular SciencesArizona State UniversityTempe 85287USA School of sciences Sun Yat-sen UniversityShenzhen 518107China

Atomic structure and electronic band structure are fundamental properties for understanding the mechanism of superconductivity. Motivated by the discovery of pressure-induced high-temperature superconductivity at 80 K in the bilayer Ruddlesden-Popper nickelate La_(3)Ni_(2.O_(7), the atomic structure and electronic band structure of the trilayer nickelate La_(4)Ni_(3)O_(10) under pressure up to 44.3 GPa are investigated. A structural transition from the monoclinic P2.(1)/a space group to the tetragonal I4/mmm around 12.6-13.4 GPa is identified, accompanied by a drop of resistance below 7 K. Density functional theory calculations suggest that the bonding state of Ni 3d_(z^(2.) orbital rises and crosses the Fermi level at high pressures, which may give rise to possible superconductivity observed in resistance under pressure in La_(4)Ni_(3)O_(10). The trilayer nickelate La_(4)Ni_(3)O_(10) shows some similarities with the bilayer La_(3)Ni_(2.O_(7) and has unique properties, providing a new platform to investigate the underlying mechanism of superconductivity in nickelates.

关键词： La_(4)Ni_(3)O_(10) high pressure synchrotron X-ray diffraction structural transition DFT calculations

Preliminary Scientific Results of Chang'E-1 Lunar Orbiter:Based on Payloads Detection Data in the First Phase

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空间科学学报 2008年第5期28卷 361-369页

作者： OUyang Ziyuan JIANG Jingshan LI Chunlai SUN Huixian ZOU Yongliao LIU Jianzhong LIU Jianjun ZHAO Baochang REN Xin yang Jianfeng ZHANG Wenxi {2. Jianyu MOU Lingli CHANG Jin ZHANG Liyan {2. Huanyu LI Yongquan ZHANG Xiaohui ZHENG Yongchun {2. shijin BIAN Wei chinese Academy of sciences Beijing 100864

Chang'E-1 lunar Orbiter was launched by Long March 3A rocket from Xichang Satel-lite Launch center at 18:05BT(beijing Time) Oct.2.,*** is the first step of its ambitious three-stage moon program,a new milestone in the {2. space exploration *** primary science objectives of Chang'E-1 lunar orbiter are to obtain three-Dimension(3D) stereo images of the lunar surface,to analyze the distribution and abundance of elements on the surface,to investigate the thickness of lunar soil,evaluate helium-3 resources and other characteristics,and to detect the space environment around the *** achieve the above four mission objectives,eight sets of scientific instruments are chosen as the payloads of the lunar orbiter,including a CCD stereo camera(CCD),a Sagnac-based interferometer spectrometer(ⅡM),a Laser Altimeter(LAM),a Microwave Radiometer(MRM),a Gamma-Ray Spectrometer(GRS),an X-ray spectrometer(XRS),a High-Energy Particle Detector(HPD),and two Solar Wind Ion Detectors(SWID).The detected data of the payloads show that all payloads work *** paper introduces the status of payloads in the first phase and preliminary scientific results.

关键词：嫦娥一号空间研究中国宇航员

Wheat straw burning and its associated impacts on beijing air quality

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science china Earth {2. 2008年第3期51卷 403-414页

作者： LI LingJun wang Ying ZHANG Qiang LI JinXiang yang XiaoGuang JIN Jun beijing Municipal Environmental Monitoring center Beijing 100044China Central University for Nationalities Beijing 100081China Department of Geography and Resource Management Institute of Space and Earth Information Sciencethe Chinese University of Hong KongHong KongChina

Based on MODIS images, large-scale flow field charts and environmental monitoring data, we thor- oughly analyzed the spatial distribution of wheat straw burning in North china, with focus on its envi- ronmental impacts on the air quality of beijing and pollution transport paths. And we anatomized changes of air quality in beijing under the impacts of pollution generated by wheat straw burning around. The results indicate that: (1) The North china Plain, a winter-wheat growing area, is the main source of pollutants induced by wheat straw burning in beijing. The direction of south-west is the dominant heavy pollution transport path. (2. Impacts of wheat straw burning on air quality are mainly manifested by significantly increasing CO concentration. (3) Precursors of O3 generated by wheat straw burning, combining with favorable meteorological conditions, can induce increasing O3 concentration greatly. NO concentration will be greatly increased due to decreasing O3 concentration at night. (4) Atmospheric particles, especially the fine ones, from wheat straw burning exert considerable influ- ence on beijing air quality. (5) Different contributions of wheat straw burning to pollutants are identified. Ratios of PM10/SO2. CO/SO2. etc., can be applied to indicate pollution extent of wheat straw burning. High ratios of PM10/SO2.and CO/SO2.show that the air quality was heavily impacted by wheat straw burning and these ratios can be employed as indicators of contribution of wheat straw burning to the degradation of beijing air quality. (6) Randomness of wheat straw burning activities renders random outbreak of air pollution of this type. Regional and extensive wheat straw burning activities can cause serious air pollution event.

关键词： beijing wheat straw burning air pollution source transport path