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介绍一种新的超近距离 (小于 1m)靶距测量技术。该技术已于 1999年 5月和 1999年 7月成功地用于武汉固定卫星激光测距站和“中国地壳运动观测网络”的流动卫星激光测距系统中 ,校准卫星激光测距系统内各种光路、电路的延时。经这两个系统长期观测 ,证明此技术运行可靠 ,效果很好 ,校准精度优于 1cm 相似文献
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一、概述 本世纪后期,新兴的空间大地测量技术得到了广泛应用。目前空间大地测量技术主要归为六类:①全球卫星定位系统(GPS):②射电源甚长基线干涉测量(VLBI);③卫星激光测距(SLR);④卫星测高;⑤卫星重力梯度测量;⑥双向无线电卫星定位。 ——SLR和VLBI是目前进行地心系统大地定位、测定地球自转参数和板块运动精度最高的两项技术; 相似文献
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徐炳麟 《大地测量与地球动力学》1981,(1)
利用人卫激光测距系统测量地面点至卫星间的距离,首次成功的事例是在1964年。时至今日,全球巳拥有三十多台,分布在各个大陆不同的国家,从事于地球动力学问题的研究。其中第三代的测距精度可达1—3厘米。 相似文献
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基于常规计数型TDC设计思想,通过FPGA芯片的内部PLL延迟相位技术和内部资源构建延迟链改进常规计数型TDC,时间间隔测量精度可达200 ps。该方法对激光测距、三维激光扫描仪、绝对重力仪等仪器中精密时间测量系统的研究具有实际意义。 相似文献
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高精度卫星轨道是提高卫星应用水平的基础,卫星精密定轨方法主要基于卫星轨道动力学理论．通过跟踪卫星轨迹的测轨技术,将几何和动力学信息进行融合。地震电磁卫星拟采用星载GPS和综合轨道求解方法进行精密定轨．并辅之以人卫激光测距,其定轨的精度可达厘米级。 相似文献
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流动卫星激光测距（SLR）系统实现了kHz高重复频率测距、白天测距等功能,具有测距精度高、探测效率高等特点,并能有效解决中国人造卫星激光测距网分布不均的问题。目前,仪器远程控制技术可有效提高卫星激光测距系统的自动化水平,并最终实现无人值守功能,但该技术首先要解决的问题就是远程通信。本文采用GSM模块并结合单片机嵌入式系统,设计了一套GSM远程通信系统。经测试,该系统可实现点对点的通信,出现错误时能够报错及报警,符合预期结果。 相似文献
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编队卫星InSAR系统的相位同步分析 总被引：1，自引：0，他引：1
编队卫星InSAR系统属多基雷达系统,依靠编队卫星构型形成干涉所需的基线。一发多收工作模式下的编队卫星InSAR高程测量系统,协同工作的雷达间必须建立时间同步、相位同步和空间同步,其同步精度将影响InSAR系统的功能与性能。三大同步中,相位同步误差直接影响SAR复影像的相位误差,从而影响系统的高程测量精度。本文根据编队卫星条件下SAR成像的要求,对相位同步的要求进行了分析,并给出了由于相位不同步所引起的相位误差对InSAR高程测量精度影响。分析结果表明,编队卫星InSAR系统对于相位同步的要求包含两个方面:一是为保证被动雷达能够对回波实现相参成像,在整个合成孔径时间内,主动和被动两个雷达在载波相位上必须保持确定和可知的关系,且其差值随系统距离向分辨率的不同必须限定在一定范围内;二是在整个干涉数据的录取时间里,主动和被动两个雷达载波相位同步误差不能超过高程测量的精度要求所允许的误差。 相似文献
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卫星激光测距系统(SLR)的测距值,一般归算到方位轴和俯仰轴的空间交会点(几何旋转中心),其空间坐标的确定是观测数据得以应用的前提。介绍一种GNSS天线的安装方案,该方案克服望远镜体积较大,且形状不规则,几何旋转中心难以接近测量的问题,基于BERNESE计算软件,联合多个IGS站,解算出流动SLR几何旋转中心坐标的观测结果,整体精度优于4 mm。 相似文献
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感应同步器数显表对人卫激光测距的影响谭业春叶文蔚（国家地震局地震研究所，武汉，４３００７１）１前言卫星激光测距的成功率在于对微弱激光回波的检测与转台定位的精确程度，后者由转台跟踪精度决定。而转台的跟踪精度（即对卫星的瞄准精度）取决于感应同步器数显表的... 相似文献
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宋明英 《大地测量与地球动力学》2003,23(1)
神州 4号轨道舱下表面装有激光反射器 ,这是国内首次在航天器上安装激光反射器。其作用是进行飞船轨道舱的综合精密定轨试验。飞船上装载的用于探测海面高度、有效波高与大洋环流的微波高度计对海面的测量结果 ,必须配合飞船本身的精确位置和轨道才能获得最终成果。神州 4号飞船采用的卫星激光测距、船载ＧＰＳ定位和统一波段测速测距系统三种综合精密定轨技术中 ,卫星激光测距技术的单次测距精度最高 ,目前可达 1ｃｍ左右。该技术仅要求在飞船上装一个直径为 2 0ｃｍ、重量约 0 .8ｋｇ的简单的光学仪器———激光反射器。因其没有电子原件 … 相似文献
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Based on the hydrographic data in austral summer during the 22nd Antarctic Expedition of China(2005/2006),some features can be found about the northern margin of Emery ice shelf as follows.The heat content in the surface layer(0-50 m) at the eastern end and the western end of the ice-shelf margin is much higher than that at the middle.The upper mixing-layer depth and the seasonal thermocline depth at the middle of the ice-shelf northern margin are much shallower than those at the both ends.However there is much less difference between the middle and the ends in the bottom layer.The remote sensing photos show that the inhomogeneity in the surface-layer water is closely related to the spatial distribution of the floes and polynia in the area. 相似文献
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Phylogenetic analysis based on 16S rDNA of 8 strains of cultivable bacteria isolated from Arctic sea-ice was studied.The results showed that strain BJ1 belonged to genus Planococcus,which was a genus of low mole percent G C gram-positive bacteria;strain BJ6 belonged to genus Burkholderia of β-proteobacteria and the rest 6 strain all belonged to γ-proteobacteria,of which strain BJ8 was a species of Pseudoalteromonas,strain BJ2-BJ5 and BJ7 were members of genus Psychrobacter.Phylogenetic analysis also indicated that bacteria of genus Psychrobacter of the isolates formed a relatively independent phylogenetic cluster in comparison with other bacteria belonged to genus Psychrobacter. 相似文献
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《极地研究(英文版)》2014,(3)
正1 Aims and Scope Advances in Polar Science(APS)is an international,peer-reviewed journal jointly sponsored by the Polar Research Institute of China and the Chinese Arctic and Antarctic Administration.APS is a comprchensive academic journal dedicated to presentation of multi-disciplinary achievements in Arctic and Antarctic expeditions and research.Its primary purpose is to publish achievements in fundamental research,applied 相似文献
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《山地科学学报》2014,(4):I0004-I0009
<正>AIMS AND SCOPE(Editorial Policy)The Journal of Mountain Science(JMS)is devoted to mountains and their surrounding lowlands-ecoregions of particular global importance,with a particular emphasis on the important highlands/mountains in the world,such as the Tibetan Plateau,the Himalayas,the Alps,the Andes,the Rockies and many other mountain ranges of our planet. 相似文献
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《山地科学学报》2014,(4)
<正>The Journal of Mountain Science(JMS),founded in2004,is an international English-language journal on mountain sciences.JMS is supervised by the Chinese Academy of Sciences(CAS),sponsored by the Chengdu Institute of Mountain Hazards and Environment,CAS,published by Science Press China,and distributed by Springer exclusively throughout the world(excluding Mainland China).The JMS is published bimonthly,fulltexted in SpringerLink and CNKI,indexed/abstracted by 相似文献
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Livestock behaviour in the Pyrenees includes free grazing and a long resting period that provokes the accumulation of dung and urine in some places,so-called camping areas. The aims of this study were （i） to analyze any change in floral composition,and in nutritional and chemical contents of plants in a livestock camping area; and （ii） to relate the floral composition with soil chemical properties. In a linear transect,five sampling zones were established,from the centre of the camping area to the surrounding Nardus stricta-dominant pasture. The above ground plant biomass and the topsoil were sampled in each zone with 6 replicates per zone. Plant species were classified and weighed to calculate above ground biomass,nutritional and chemical contents,and Shannon diversity and evenness indices. Additionally,soils were sampled in two periods,at the beginning and at the end of grazing period. Soil available nutrients （nitrate,ammonium,phosphorus,potassium,calcium and magnesium）,total nitrogen,organic carbon and pH were measured.
Plant chemical contents （protein,lignin and others） were significantly related to the proportions of grasses,legumes and other plants; so,the protein content is positively correlated with legumes plant biomass while lignin content is negatively correlated with grasses. Both plant and soil nutrients increased linearly towards the centre of the camping area. However,the relationship among plant species richness,diversity and evenness relative to its position along the studied transect was bell-shaped. From the outskirts to the centre of the camping area,plants with low nutrient demand were progressively replaced by those with medium and high nutrients demand and by pioneers.
Nardus stricta-dominant pasture has low plant diversity and plant nutrient content as well as a poor soil nutrient availability. The presence of the camping area introduced patches with more soil nutrients and new species in the large spatial scale. However at a small spatial scale,the strong soil nutrien 相似文献
Plant chemical contents （protein,lignin and others） were significantly related to the proportions of grasses,legumes and other plants; so,the protein content is positively correlated with legumes plant biomass while lignin content is negatively correlated with grasses. Both plant and soil nutrients increased linearly towards the centre of the camping area. However,the relationship among plant species richness,diversity and evenness relative to its position along the studied transect was bell-shaped. From the outskirts to the centre of the camping area,plants with low nutrient demand were progressively replaced by those with medium and high nutrients demand and by pioneers.
Nardus stricta-dominant pasture has low plant diversity and plant nutrient content as well as a poor soil nutrient availability. The presence of the camping area introduced patches with more soil nutrients and new species in the large spatial scale. However at a small spatial scale,the strong soil nutrien 相似文献
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文章概略介绍了利用卫星进行定位的原理 ;由卫星信号传播、信号接收和SA政策等引起的理论误差 ;给出了多种快速、高精度定位的工作模式和观测点选择的原则 ;列出了将WGS - 84坐标转换为我国坐标的公式及解算参数的具体方法 ,供读者在GPS工作中参考。 相似文献