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地球球观认知分析:以谷歌地球上的寻路任务为例 被引量:2
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作者 应申 张雯博 +1 位作者 苏俊如 黄丽娜 《测绘学报》 EI CSCD 北大核心 2021年第6期739-748,共10页
地理空间认知影响人类与空间相关的行为。本文提出了地球空间观(球观)的概念,以地球上不同区域找寻过程作为试验环境,研究被试者在数字地球球体(Google Earth)上如何进行定向、定位和目的地寻找,分析球观模式下对地球球体的空间认知过... 地理空间认知影响人类与空间相关的行为。本文提出了地球空间观(球观)的概念,以地球上不同区域找寻过程作为试验环境,研究被试者在数字地球球体(Google Earth)上如何进行定向、定位和目的地寻找,分析球观模式下对地球球体的空间认知过程。借助眼动仪记录的数据将被试者的读图过程可视化并且进行思维过程分析。结果发现,在地球球体上,结合了即时相对位置判断和方向定位的目的地搜寻过程是被试者球观建立过程的综合表现。 展开更多
关键词 球观 眼动分析 空间认知 数字地
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远征、探险、朝圣:球迷异地观球现象的文化学释读 被引量:1
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作者 路云亭 《河北体育学院学报》 2020年第2期22-29,共8页
足球联赛制中的主客场赛制增加了球迷看球的成本,部分球迷却早已习惯了异地观球,还很少抱怨奔波之苦,甚至,奔赴客场观球的球迷会获得一种独特的快感,其中有旅行、探险之乐趣,还有远征、朝圣之收益。球迷异地观球的动机来自其对足球高度... 足球联赛制中的主客场赛制增加了球迷看球的成本,部分球迷却早已习惯了异地观球,还很少抱怨奔波之苦,甚至,奔赴客场观球的球迷会获得一种独特的快感,其中有旅行、探险之乐趣,还有远征、朝圣之收益。球迷异地观球的动机来自其对足球高度的精神依赖,其以朝圣心理为核心要素。足球朝圣行为具有高度的仪式感和独特美学价值,展示了足球丰富多元的文化镜像。异地观球的朝圣者往往会有令人费解的超常之举,但他们有求取圆满的动机,也将获得超常的体验。球迷朝圣的宗教学与人类学价值要大于其文化学与社会学的意义。 展开更多
关键词 迷朝圣 异地 旅行 自虐 精神异化
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中国商人南非观球记
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作者 黄波 《商界(评论)》 2010年第8期26-33,共8页
当2004年5月15日,FIFA(国际足联)宣布南非取得2010年世界杯举办权、古老的非洲大地将首次举办这项世界瞩目的体育赛事时.整个南非都沸腾了,德高望重的南非前总统曼德拉在瑞士苏黎世亲历了这一难忘时刻,时任南非总统的姆贝基曾说... 当2004年5月15日,FIFA(国际足联)宣布南非取得2010年世界杯举办权、古老的非洲大地将首次举办这项世界瞩目的体育赛事时.整个南非都沸腾了,德高望重的南非前总统曼德拉在瑞士苏黎世亲历了这一难忘时刻,时任南非总统的姆贝基曾说:“这是南非向世界展示自己的黄金时机”。 展开更多
关键词 中国 商人 南非
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介观结构对Fe基纳米晶粉末巨磁阻抗效应的影响
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作者 杨全民 许启明 +2 位作者 方允樟 王玲玲 陈涛 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 2007年第12期2124-2127,共4页
根据Fe基纳米晶粉末、粉芯的制作和巨磁阻抗(GMI)效应的测试,经过抽象化处理,提出了解释Fe基纳米晶粉末GMI效应的理论模型——球介观模型。分析表明,影响Fe基纳米晶粉末磁阻抗的根本因素有:与纳米晶粒磁化场强度相关的D函数,决定D函数... 根据Fe基纳米晶粉末、粉芯的制作和巨磁阻抗(GMI)效应的测试,经过抽象化处理,提出了解释Fe基纳米晶粉末GMI效应的理论模型——球介观模型。分析表明,影响Fe基纳米晶粉末磁阻抗的根本因素有:与纳米晶粒磁化场强度相关的D函数,决定D函数的因素为纳米晶粒的半径R,磁导率μ,电导率σ,外加直流磁场的大小Hex,外加交变磁场的角频率ω和幅值H0,而且μ,σ,ω,R之间又相互影响、相互竞争、相互制约。利用该模型成功地解释了外加直流磁场对Fe基纳米晶粉末磁阻抗频谱曲线的共振频率、共振幅值、灵敏度变化规律的影响。 展开更多
关键词 Fe基纳米晶粉末 巨磁阻抗效应 模型 频率函数
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Comparative Analysis of Microwave Brightness Temperature Data in Northeast China Using AMSR-E and MWRI Products 被引量:7
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作者 GU Lingjia ZHAO Kai +1 位作者 ZHANG Shuwen ZHANG Shuang 《Chinese Geographical Science》 SCIE CSCD 2011年第1期84-93,共10页
With such significant advantages as all-day observation, penetrability and all-weather coverage, passive mi-crowave remote sensing technique has been widely applied in the research of global environmental change. As t... With such significant advantages as all-day observation, penetrability and all-weather coverage, passive mi-crowave remote sensing technique has been widely applied in the research of global environmental change. As the sat-ellite-based passive microwave remote sensor, the Advanced Microwave Scanning Radiometer-Earth Observing Sys-tem (AMSR-E) loaded on NASA's (National Aeronautics and Space Administration of USA) Aqua satellite has been popularly used in the field of microwave observation. The Microwave Radiation Imager (MWRI) loaded on the Chi-nese FengYun-3A (FY-3A) satellite is an AMSR-E-like conical scanning microwave sensor, but there are few reports about MWRI data. This paper firstly proposed an optimal spatial position matching algorithm from rough to exact for the position matching between AMSR-E and MWRI data, then taking Northeast China as an example, comparatively analyzed the microwave brightness temperature data derived from AMSR-E and MWRI. The results show that when the antenna footprints of the two sensors are filled with either full water, or full land, or mixed land and water with ap-proximate proportion, the errors of brightness temperature between AMSR-E and MWRI are usually in the range from -10 K to +10 K. In general, the residual values of brightness temperature between the two microwave sensors with the same spatial resolution are in the range of ±3 K. Because the spatial resolution of AMSR-E is three times as high as that of MWRI, the results indicate that the quality of MWRI data is better. The research can provide useful information for the MWRI data application and microwave unmixing method in the future. 展开更多
关键词 AMSR-E MWRI FY-3A satellite brightness temperature spatial resolution spatial position matching Northeast China
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A Thin Cloud Removal Method from Remote Sensing Image for Water Body Identification 被引量:4
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作者 ZHENG Wei SHAO Jiali +1 位作者 WANG Meng HUANG Dapeng 《Chinese Geographical Science》 SCIE CSCD 2013年第4期460-469,共10页
In this paper,a thin cloud removal method was put forward based on the linear relationships between the thin cloud reflectance in the channels from 0.4 μm to 1.0 μm and 1.38 μm.Channels of 0.66 μm,0.86 μm and 1.... In this paper,a thin cloud removal method was put forward based on the linear relationships between the thin cloud reflectance in the channels from 0.4 μm to 1.0 μm and 1.38 μm.Channels of 0.66 μm,0.86 μm and 1.38 μm were chosen to extract the water body information under the thin cloud.Two study cases were selected to validate the thin cloud removal method.One case was applied with the Earth Observation System Moderate Resolution Imaging Spectroradiometer(EOS/MODIS) data,and the other with the Medium Resolution Spectral Imager(MERSI) and Visible and Infrared Radiometer(VIRR) data from Fengyun-3A(FY-3A).The test results showed that thin cloud removal method did not change the reflectivity of the ground surface under the clear sky.To the area contaminated by the thin cloud,the reflectance decreased to be closer to the reference reflectance under the clear sky after the thin cloud removal.The spatial distribution of the water body area could not be extracted before the thin cloud removal,while water information could be easily identified by using proper near infrared channel threshold after removing the thin cloud.The thin cloud removal method could improve the image quality and water body extraction precision effectively. 展开更多
关键词 thin cloud removal water body Moderate Resolution Imaging Spectroradiometer(MODIS) Medium Resolution Spectral Imager(MERSI) Visible and Infrared Radiometer(VIRR)
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Evaluation of AMSR-E——Derived Soil Moisture over Northern China 被引量:7
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作者 ZHANG An-Zhi JIA Gen-Suo +3 位作者 WANG He-Song ZHAO Tian-Bao FENG Jin-Ming MA Zhu-Guo 《Atmospheric and Oceanic Science Letters》 2011年第4期223-228,共6页
In this study,the authors evaluated two re-motely sensed surface soil moisture datasets derived from the Advanced Microwave Scanning Radiometer of the Earth Observing System (AMSR-E) over northern China.The soil moist... In this study,the authors evaluated two re-motely sensed surface soil moisture datasets derived from the Advanced Microwave Scanning Radiometer of the Earth Observing System (AMSR-E) over northern China.The soil moisture datasets were derived from algorithms developed by the National Snow and Ice Data Center (NSIDC) and jointly developed by the Vrije Universiteit Amsterdam and NASA Goddard Space Flight Center (VUA-NASA).The NSIDC and VUA-NASA products were compared to in situ soil moisture data from nine enhanced coordinated observation stations.The VUA-NASA dataset presented a strong correlation with top layer in situ soil moisture observations,and the correla-tion coefficients ranged from 0.34 to 0.73 (p<0.01).The correlation coefficients decreased as the observed soil layer depth increased.The correlation coefficients be-tween the NSIDC retrievals and the top layer in situ ob-servations were between 0.10 and 0.62 (p<0.01).Fur-thermore,VUA-NASA soil moisture variations agreed well with in situ soil moisture dynamics and responded sensitively to precipitation events.In contrast,the NSIDC dataset failed to capture signals of soil moisture dynamics.The analyses demonstrated that the VUA-NASA product was capable of representing soil moisture conditions over northern China. 展开更多
关键词 soil moisture AMSR-E coordinated observation northern China
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A Neural Network Method for Monitoring Snowstorm: A Case Study in Southern China 被引量:2
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作者 MAO Kebiao MA Ying +4 位作者 XIA Lang SHEN Xinyi SUN Zhiwen HE Tianjue ZHOU Guanhua 《Chinese Geographical Science》 SCIE CSCD 2014年第5期599-606,共8页
It has been observed that low temperature, rainfall, snowfall, frost have never occurred over the past 50 years in the southern China, and weather in this area is very complex, so the monitoring equipments are few. Op... It has been observed that low temperature, rainfall, snowfall, frost have never occurred over the past 50 years in the southern China, and weather in this area is very complex, so the monitoring equipments are few. Optical and thermal infrared remote sensing is influenced much by clouds, so the passive microwave Advanced Microwave Scanning Radiometer-Earth Observing System (AMSR-E) data are the best choice to monitor and analyze the development of disaster. In order to improve estimation accuracy, the dynamic learn- ing neural network was used to retrieve snow depth. The difference of brightness temperatures of TB18.7v and TB36.sv, TBI8.7H and TB36.sH, TB23,sv and TB89v, TBz3.8H and TB89H are made as four main input nodes and the snow depth is the only one output node of neural network. The mean and the standard deviation of retrieval errors are about 4.8 cm and 6.7 cm relative to the test data of ground measurements. The application analysis indicated that the neural network can be utilized to monitor the change of snow intensity distribution through passive microwave data in the complex weather of the southern China. 展开更多
关键词 SNOWSTORM neural network snow depth passive microwave Advanced Microwave Scanning Radiometer-Earth Observing System (AMSR-E)
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Earth Observation as a Support to Improve Water Use in Irrigated Agriculture 被引量:2
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作者 E. V. Palacios L. S. Palacios +1 位作者 J. C. Rodriguez J. E. S. Palacios 《Journal of Agricultural Science and Technology》 2010年第6期1-9,共9页
By the end of sixties, several satellites were launched to observe the earth; among them the Landsat missions have been important to study natural resources, especially in agriculture. Currently, Landsat 7, with some ... By the end of sixties, several satellites were launched to observe the earth; among them the Landsat missions have been important to study natural resources, especially in agriculture. Currently, Landsat 7, with some problems, and Landsat 5 are useful to evaluate crop development. A project called "Participatory multi-Level EO-assisted tools for Irrigation water management and Agricultural Decision-Support" (PLEIADES) was financed by the European Commission. This project considers eleven countries and 23 research institutions, Mexico being one of the selected countries. Landsat images are a basic tool of this project. Some of the results obtained in this study are presented in this article. By using w^getation indices obtained by the combinations of reflectances in different bands of the electromagnetic spectrum, it has been possible to estimate the behavior of several biophysical parameters of crops which are used to evaluate plant development, water stress, spatial soil variation, and the effect of plagues and crop diseases. To facilitate this process, a visor was developed, named SPIDER (System of Participatory Information Decision support and Expert knowledge for River basin management) whose use in this work is explained. 展开更多
关键词 SATELLITES reflectances vegetation indices water stress SPIDER.
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Comparison of Construction Method for DEM Simulation of Ellipsoidal Particles 被引量:10
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作者 陶贺 钟文琪 金保升 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第7期800-807,共8页
Discrete element model was developed to simulate the ellipsoidal particles moving in the moving bed. Multi-element model was used to describe a ellipsoidal particle, the contact detection algorithm of ellipsoidal part... Discrete element model was developed to simulate the ellipsoidal particles moving in the moving bed. Multi-element model was used to describe a ellipsoidal particle, the contact detection algorithm of ellipsoidal particle was developed, and both contact force and gravity force were considered in the models. The simulation results were validated by our experiment. Three algorithms for representing an ellipsoidal particle were compared in macro and micro aspects. The results show that there exists big difference in the microscopic parameters such as kinetic energy, rotational kinetic energy, deformation, contact force and collision number which leads to the difference of macroscopic parameters. The relative error in the discharge rate and tracer particle position is the largest between 3-tangent-element representation and experimental results. The flow pattern is similar for the 5-element and 3-intersection representations. The only difference is the discharge rate of 5-element representation is larger than the experimental value and that of the 3-intersection representation has the contrary result. Finally the 3-intersection- element reoresentation is chosen in the simulation due to less comouting time than that of the 5-element renresentation. 展开更多
关键词 ellipsoidal particle multi-element model moving bed discrete element model construction method
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Dust particles in free troposphere over Chinese desert region revealed from balloon borne measurements under calm weather conditions
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作者 HABIB Ammara CHEN Bin +7 位作者 SHI Guangyu IWASAKA Yasunobu NATH Debashis KHALID Bushra TAN Saichun MAHMOOD Tariq JIAO Reguang NTWALI Didier 《Atmospheric and Oceanic Science Letters》 CSCD 2019年第1期12-20,共9页
The Taklamakan Desert in China is one of the major source regions for Asian dust particles.All balloon-borne measurements in this report were carried out in Dunhuang,in the Taklamakan Desert,during calm weather condit... The Taklamakan Desert in China is one of the major source regions for Asian dust particles.All balloon-borne measurements in this report were carried out in Dunhuang,in the Taklamakan Desert,during calm weather conditions.The aerosol number concentration,size distribution,mass concentration,and horizontal mass flux due to westerly wind were investigated.The measurements were performed on 17 August 2001,17 October 2001,11 January 2002,and 30 April 2002.Five channels(0.3,0.5,0.8,1.2,and 3.6μm in diameter)were used in the Optical Particle Counter for particle measurements.The aerosol number concentration in the winter season(11 January 2002)at 3–5 km was very high.Variation of free-tropospheric aerosols on 30 April 2002 was noticeable.A super-micron range was noticeable in the size distribution of all the measurements.Many variations in temperature and aerosol concentration were found at these inversion points.High values of estimated mass concentration of aerosols were frequently observed in the atmosphere near the ground(i.e.,1–2 km);and interestingly,relatively high concentrations were frequently detected above 2 km from the surface.Wind patterns observed using ERA-Interim data at 500 and 850 hPa showed that westerly winds dominated in the Taklamakan Desert during the observation period.The average horizontal mass flux of background Asian dust due to westerly wind was observed to fall within the range of 58.5–1219 tons km?2 d?1.Vertical profiles of aerosol number concentrations showed that significant transport of aerosols dominated in the westerly region(i.e.,4–7 km). 展开更多
关键词 AEROSOLS optical particle counter balloon-borne measurements Dunhuang
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Validation of Land Surface Temperature Derived from 37-GHz AMSR-E over Northern China
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作者 ZHANG An-Zhi JIA Gen-Suo +1 位作者 WANG He-Song ZHAO Tian-Bao 《Atmospheric and Oceanic Science Letters》 2011年第5期257-263,共7页
A validation study of land surface temperature (LST) obtained from the Ka band (37 GHz) vertically polarized brightness temperature over northern China is presented.The remotely sensed LST derived jointly by the Vrije... A validation study of land surface temperature (LST) obtained from the Ka band (37 GHz) vertically polarized brightness temperature over northern China is presented.The remotely sensed LST derived jointly by the Vrije Universiteit Amsterdam and the NASA Goddard Space Flight Center (VUA-NASA) from the Advanced Microwave Scanning Radiometer-Earth Observing System (AMSR-E) were compared to the daily in-situ top soil temperature/infrared surface temperature observations from eleven/three Enhanced Coordinated Observation stations in arid and semi-arid regions of northern China.The VUA-NASA LST from the descending path exhibited a stronger correspondence to the in-situ infrared surface temperature than soil temperature observations,whereas correlations (R 2) of the latter ranged from 0.41 to 0.86.Meanwhile,the ascending overpass LST was generally warmer than the in-situ soil temperature observations at all stations,and the correlation (R 2) was between 0.07 and 0.72.Furthermore,the correlation of the descending path was generally greater than that of the ascending path at the same station.The descending path VUA-NASA LST was sensitive to precipitation and presented good agreement with ground temperature dynamics.The analyses demonstrated that the descending overpass LST was reliable to reflect reasonable patterns of temperature dynamics for land surface temperature in the region. 展开更多
关键词 land surface temperature VALIDATION AMSR-E soil temperature northern China
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Model-Simulated Atmospheric Carbon Dioxide: Comparisons with Satellite Retrievals and Ground-Based Observations
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作者 WANG Jiang-Nan TIAN Xiang-Jun FU Yu 《Atmospheric and Oceanic Science Letters》 CSCD 2014年第6期481-486,共6页
Atmospheric CO2 concentrations from January 2010 to December 2010 were simulated using the GEOS-Chem(Goddard Earth Observing System-Chemistry) model and the results were compared to satellite Gases Observing Satellite... Atmospheric CO2 concentrations from January 2010 to December 2010 were simulated using the GEOS-Chem(Goddard Earth Observing System-Chemistry) model and the results were compared to satellite Gases Observing Satellite(GOSAT) and ground-based the Total Carbon Column Observing Network(TCCON) data. It was found that CO2 concentrations based on GOSAT satellite retrievals were generally higher than those simulated by GEOS-Chem. The differences over the land area in January and April ranged from 1 to 2 ppm, and there were major differences in June and August. At high latitudes in the Northern Hemisphere in June, as well as south of the Sahara, the difference was greater than 5 ppm. In the high latitudes of the Northern Hemisphere the model results were higher than the GOSAT retrievals, while in South America the satellite data were higher. The trend of the difference in the high latitudes of the Northern Hemisphere and the Saharan region in August was opposite to June. Maximum correlation coefficients were found in April, reaching 0.72, but were smaller in June and August. In January, the correlation coefficient was only 0.36. The comparisons between GEOS-Chem data and TCCON observations showed better results than the comparison between GEOS and GOSAT. The correlation coefficients ranged between 0.42(Darwin) and 0.92(Izana). Analysis of the results indicated that the inconsistency between satellite observations and model simulations depended on inversion errors caused by data inaccuracies of the model simulation's inputs, as well as the mismatch of satellite retrieval model input parameters. 展开更多
关键词 GEOS-CHEM GOSAT TCCON CO2 concentration COMPARISON
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The Istituto Nazionale di Geofisica e Vulcanologia Data Management System for the Arctic Sciences
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作者 Umberto Apponi Vincenzo Romano +7 位作者 Giorgiana De Franceschi Paola Del Carlo Ilaria Isola Patrizia Macri Giovanni Muscari Leonardo Sagnotti Luca Spogli Stefano Urbini 《Journal of Environmental Science and Engineering(B)》 2016年第11期549-556,共8页
The brokering approach can be successfully used to overcome the crucial question of searching among enormous amount of data (raw and/or processed) produced and stored in different information systems. In this paper,... The brokering approach can be successfully used to overcome the crucial question of searching among enormous amount of data (raw and/or processed) produced and stored in different information systems. In this paper, authors describe the Data Management System the DMS (Data Management System) developed by INGV (Istituto Nazionale di Geofisica e Vulcanologia) to support the brokering system GEOSS (Global Earth Observation System of Systems) adopted for the ARCA (Arctic Present Climate Change and Past Extreme Events) project. This DMS includes heterogeneous data that contributes to the ARCA objective (www.arcaproject.it) focusing on multi-parametric and multi-disciplinary studies on the mechanism (s) behind the release of large volumes of cold and fresh water from melting of ice caps. The DMS is accessible directly at the www.arca.rm.ingv.it, or through the IADC (Italian Arctic Data Center) at http://arcticnode.dta.cnr.it/iadc/gi-portal/index.jsp that interoperates with the GEOSS brokering system (http://www.geoportal.org0 making easy and fast the search of specific data set and its URL. 展开更多
关键词 BROKERING ARCA (Arctic Present Climate Change and Past Extreme Events) IADC (Italian Arctic Data Center) GEOSS(Global Earth Observation System of Systems) DMS (Data Management System) data metadata INSPIRE (Infrastructure for SpatialInformation in Europe) ISO (International Organization for Standardization) 19115 and 19119.
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Projected Changes in NO_x Emissions from Lightning as a Result of 2000–2050 Climate Change
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作者 JIANG Hui LIAO Hong 《Atmospheric and Oceanic Science Letters》 CSCD 2013年第5期284-289,共6页
Lightning is one of the most important natural sources of atmospheric NOx.The authors investigate the2000–2050 changes in NOx emissions from lightning using the global three-dimensional Goddard Earth Observing System... Lightning is one of the most important natural sources of atmospheric NOx.The authors investigate the2000–2050 changes in NOx emissions from lightning using the global three-dimensional Goddard Earth Observing System chemical transport model(GEOS-Chem)driven by meteorological fields from the Goddard Institute for Space Studies(GISS)general circulation model(GCM)3.Projected changes in climate over 2000–2050are based on the Intergovernmental Panel on Climate Change(IPCC)A1B scenario.The global NOx emission from lightning is simulated to be 4.8 Tg N in present day and to increase by about 16.7%over 2000–2050 as a result of the future climate change.The largest present-day emissions and climate-induced changes are found in the upper troposphere in the tropics.Regionally in eastern China(20–55 N,98–125 E),NOx emissions from lighting is simulated to be 0.3 Tg N(6.3%of the global total emission)in present day and to increase by 26.7%over2000–2050.The simulated changes in NOx from lightening correspond well with the projected future changes in convective precipitation. 展开更多
关键词 NOx LIGHTNING climate change
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Observed characteristics of atmospheric ducts over the South China Sea in autumn 被引量:5
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作者 成印河 周生启 +4 位作者 王东晓 鲁远征 黄科 姚景龙 游小宝 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2016年第3期619-628,共10页
The observed characteristics of lower atmospheric ducts over the South China Sea(SCS) were analyzed based on Global Position Systerm(GPS) radiosonde data collected four times daily during autumn open cruises from 2006... The observed characteristics of lower atmospheric ducts over the South China Sea(SCS) were analyzed based on Global Position Systerm(GPS) radiosonde data collected four times daily during autumn open cruises from 2006 to 2012.Duct occurrence,thickness,and strength over the SCS were about 40%,150-m thick,and 8 M units,respectively,which were larger than during the summer monsoon period.Most ducts occurred at heights <1 500 m and these ducts easily trap electromagnetic wave clusters with wavelengths <2 m.Diurnal variation of the SCS ducts appeared evident.They occurred more often at midnight at higher altitudes(about 1 100 m),with a thickest layer of about 145 m and less frequently during the evening at lower altitudes(about 800 m),with a thinnest layer of about 125 m.Moreover,ducts during the daytime at a mean height of about 900 m,with the greatest strength of about 10 M units.Furthermore,all duct variables observed over the SCS in autumn decreased from north to south.These findings are useful not only in the design of radar and communication systems,but also for evaluating possible effects of anomalous propagation on meteorological radar and military applications. 展开更多
关键词 GPS radiosonde atmospheric ducts AUTUMN statistical characteristics
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Application of GPS technology to build a mine-subsidence observation station 被引量:16
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作者 LU Wei-cai CHENG Shi-guang +1 位作者 YANG Hai-sheng LIU Da-peng 《Journal of China University of Mining and Technology》 EI 2008年第3期377-380,共4页
We propose the design of an observation station to establish a reliable datum for displacement and deformation analysis at the first working-face subsidence observation station of Liuzhuang Mine. The design considers ... We propose the design of an observation station to establish a reliable datum for displacement and deformation analysis at the first working-face subsidence observation station of Liuzhuang Mine. The design considers various geologic and mining con-ditions. Having analyzed the aims of the joint survey and the comprehensive survey, we propose design principles, and work modes, for adopting GPS technology as the position measuring technique to be used in these two stages. Baseline vectors and spatial ad-justments of the GPS network were calculated after study of data processing and quality estimation methods. A coordinate system transformation and error estimates of the transformed GPS network data are discussed. The error estimates in all stages show that the GPS control network of the observation station has sufficient accuracy and is highly efficient. The network thus provides a reli-able datum for analyzing the laws of surface displacement and deformation induced by mining. 展开更多
关键词 GPS subsidence observation station initial observation data processing flow quality evaluating
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TanDEM-X Autonomous Formation Flying System: Flight Results
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作者 Jean-Sebastien Ardaens Denis Fischer 《Journal of Mechanics Engineering and Automation》 2012年第5期332-340,共9页
The TanDEM-X mission is a scientific and commercial Earth observation mission comprising two satellites flying in close formation. The formation maintenance can be advantageously performed by an onboard autonomous sys... The TanDEM-X mission is a scientific and commercial Earth observation mission comprising two satellites flying in close formation. The formation maintenance can be advantageously performed by an onboard autonomous system, which reduces the operational efforts, provides a shorter reaction time in case of contingencies and increases the control performance. The TanDEM-X Autonomous Formation Flying (TAFF) system has been developed for this purpose and is intended to replace the ground-based formation keeping activities during routine operations. TAFF has been activated for the first time in October 2010 for commissioning, during which the autonomous usage of thrusters was prohibited. Afterwards, a closed-loop campaign was successfully conducted in March 2011, demonstrating the capability of TAFF to maintain autonomously the formation. After a brief technical description of the system, the paper presents the key results gained during the commissioning phase and the closed-loop campaign, 展开更多
关键词 Spacecraft autonomy aerospace control closed-loop control navigation systems.
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眼疲劳克服法
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《河北党风》 2003年第5期31-31,共1页
关键词 眼疲劳 克服方法 调节机能 瞬间视力
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Earth Observations in China and the World: History and Development in 50 Years
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作者 GUO Huadong 《Bulletin of the Chinese Academy of Sciences》 2013年第2期96-98,共3页
Remote sensing, which came into being at the first International Symposium on Remote Sensing of Environment (ISRSE) 50 years ago, has enabled people to obtain objecive and realistic spatial and temporal information th... Remote sensing, which came into being at the first International Symposium on Remote Sensing of Environment (ISRSE) 50 years ago, has enabled people to obtain objecive and realistic spatial and temporal information through the application of Earth observation technologies and analyze and understand the macro-level changes of the Earth system from a spaial view. The technology of Earth observaion from space has incomparable advantages in the study of the Earth. This aricle introduces the 50-year development of Earth observaion in the world and the 30-year development of Earth observaion in China and reflects on the building of China's Earth observaion system. 展开更多
关键词 Earth observation from space Earth observation system 50th anniversary of remotesensing
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