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坐标框架是描述地球形状及变化、表达地球空间信息的基础,也是拓展人类活动、促进社会发展的关键地球空间信息基础设施。随着空间大地测量观测技术的发展,地球科学及相关学科间的交叉渗透融合,利用其建立全球或区域坐标框架成为当前大地测量的主要任务。研究建立1毫米级坐标框架是国际大地测量学界21世纪的学科目标和重要挑战。本文以当前建立理论最完善、应用最广泛、精度最高的国际地球参考框架为例,描述了基于空间大地测量观测技术的坐标框架建立方法,阐述了全球及区域地心坐标框架建设的最新进展及局限性,最后针对建立1毫米级坐标框架的几个关键问题提出了研究思路。 相似文献
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大地测量学是地球科学的一个重要发展领域,通过对地球和行星几何与物理量的观测与分析,研究地球和行星几何形状、物质运动状态及其空间环境响应,为国家基础设施和国防建设提供时空和重力基准保障。随着大地测量学向地球科学基础研究和交叉应用等方面的不断延伸和快速发展,其研究水平得到了显著提高,在描绘、构建和认知地球和行星中占据了越来越重要的地位。本文基于历年来国家自然科学基金申请和资助项目,从项目类型、分支领域、依托单位、研究方向和关键词等方面进行了统计分析,梳理了学科发展特点,构建了学科架构知识图谱——大地测量学科树,以期为大地测量学领域相关学者提供参考。 相似文献
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全球大地测量观测系统(GGOS)已在地球变化监测中得到了广泛应用。本文系统介绍了综合大地测量各类观测数据,以及地质、地震等资料,开展区域地质环境稳定性大地测量监测和评价的方法。以环渤海区域和川滇区域为例,分别针对地面沉降显著、地震多发等不同地质环境特征,介绍了区域地质环境稳定性监测技术最新进展及应用成果。结果表明,针对不同地质环境背景,基于各类大地测量监测数据,结合地质、地震、水文等资料,可有效实现区域地质环境稳定性监测和评价,拓展了大地测量地球变化监测的应用领域,有重要的科学意义和实用价值。 相似文献
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胡明城先生是著名的大地测量学家,他热爱祖国,从事大地测量工作近70年。1948年从美国海军天文台和海岸大地测量局进修回国,长期担任外国测绘科学信息的研究,发表了大量论文和译述,主要著作有《等高观测手册》、《现代大地测量学》、《现代大地测量学的理论及其应用》等。2007年时逢他90岁诞辰,本文介绍他在我国大地测量学方面的贡献。 相似文献
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本文根据局部重力场逼近的虚拟质点方法,导出整体大地测量的虚拟点质量模型,给出了地面大地测量及GPS水准观测在这一模型下的观测方程,并讨论了有关问题。 相似文献
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介绍了研究空间VLBI在大地测量等领域应用的意义,探讨了空间VLBI的观测量类型、观测模型及其涉及的大地测量所关心的参数;并采用1980~2004年的VLBI观测数据进行了计算,对大地测量所关心的几种参数的计算结果进行了分析. 相似文献
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国外测绘机构大地测量的新动向 总被引:2,自引:1,他引:1
本文概述国外测绘机构大地测量的动向 ,目的在于了解全球大地测量的发展趋势 ,作为借鉴。综观各国的大地测量动向可以看出 ,高精度国家大地控制网的建立 ,都是采用 GPS,无一例外 ,而且它们之间只是细节上的差异。从各国建立高精度大地控制网的目的来看 ,都是为多学科服务的。面对这样的总趋势 ,大地测量工作者必须拓宽知识面 ,迎接新的挑战。 相似文献
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The development of relatively inexpensive satellite receivers in the early 1970's has resulted in cost-effective applications
of satellites for a variety of geodetic surveying needs. Currently achievable accuracies range from 10 to 20 centimeters.
The NAVSTAR Global Positioning System, now under development by the Department of Defense, incorporates advanced technology
which has the potential capability of revolutionizing satellite geodesy.
Several concepts for utilizing GPS signals are briefly reviewed, and another concept, called the reconstructed carrier phase
method, is described in some detail. This concept is being pursued by the Defense Mapping Agency, National Oceanic and Atmospheric
Administration, and the U.S. Geological Survey. These agencies have numerous requirements for accurate positioning. Several
prototype receivers are planned to be available for testing in mid-1982. These receivers should be highly portable, consume
little power, and obtain base line accuracies of several centimeters in several hours of observation time. However, water
vapor radiometers will be needed in order to achieve the full accuracy. Initial simulation results utilizing the reconstructed
carrier phase method are included. 相似文献
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James C. Tison Jr. 《Journal of Geodesy》1968,42(2):163-167
Summary This discussion only scratches the surface of the subject of marine geodesy. Its sole purpose is to bring into focus some
of the problems and the requirements which will arise as a result of the exploration of the sea. It seems clear at least at
this time that the geodetic accuracies obtainable over the ocean areas in general will be at least one or two orders of magnitude
less than those obtainable on land. But modern science which has produced the atom bomb, artificial satellites, soft landings
on the moon, and other highly sophisticated accomplishments, might be expected in the future to provide some means of obtaining
much higher geodetic accuracies at sea than can now be foreseen. 相似文献
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本文以有限单元法为基础,将四维整体大地测量模型与固体力学方程求解构造应力场结合起来,在四维整体大地测量方程中加入了由地壳构造运动产生的地面点重力变化的观测方程,其中包含测点的位移参数,边界结点上待求以数利用有限单元法在四维整体大地测量平差过程中推估,采用统一的插值函数。 相似文献
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介绍了凹凸体、障碍体及其震源模式相关概念,综述了地震大地测量确定凹凸体的研究进展,主要从介质结构分布(高强度异常体)、地震活动性分析和断层滑动特性三个方面探讨凹凸体确定的技术与方法,并分析了存在的问题。对活动断层凹凸体分布的精细确定研究进行了展望,今后的研究重点是开展大地测量数据联合反演确定凹凸体分布、联合大地测量与地震、地球物理数据确定凹凸体分布以及基于机器学习方法进行凹凸体分布确定。 相似文献
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甚长基线干涉测量(VLBI)因其独具的超高空间分辨率和定位精度,使其从20世纪70年代末开始就一直是各国的大地测量学研究热点。然而目前VLBI的测量水平依旧不能满足许多需要毫米级精度的科学和工程领域的需求。为促进实现全球尺度下1mm位置精度的目标,国际VLBI大地测量与天体测量服务组织(IVS)正在推进新一代VLBI全球观测系统,即VGOS。本文从组成VGOS测站的各个子系统入手,介绍了国内外当前的进展情况及未来VGOS的发展趋势,并在最后列出了现阶段依旧面临的问题和挑战。 相似文献
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Current activities and recent progress on constructive approximation and numerical analysis in physical geodesy are reported
upon. Two major topics of interest are focused upon, namely trial systems for purposes of global and local approximation and
methods for adequate geodetic application. A fundamental tool is an uncertainty principle, which gives appropriate bounds
for the quantification of space and momentum localization of trial functions. The essential outcome is a better understanding
of constructive approximation in terms of radial basis functions such as splines and wavelets.
Received: 4 May 1999 / Accepted: 21 May 1999 相似文献
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Ivan I. Mueller 《Journal of Geodesy》1981,55(4):272-285
After reviewing the overall goals of geodesy, the paper focuses on the unique properties of inertial survey systems in the
geodetic arsenal: three-dimensionality; ability to determine relative positions and changes in the anomalous components of
the earth’s gravity field; and independence of line-of-sight observations and the effects of refraction, both traditional
antagonists in geodetic operations. Inertial survey systems, including field and office computational procedures, are briefly
reviewed. Their short-comings are pointed out and certain remedies offered. Future possible improvements in hardware and software,
as well as the development of hybrid systems (e.g., with gravity gradiometers), are discussed.
“Apart from the refinement of existing techniques through the use of computers and the introduction of electromagnetic and
optical distance measurement devices, instrumental research and development has been conducted by scientists and engineers
outside the geodetic profession. This separateness of geodetic instrument research and development is seen as a deficiency
by some, because of the reduced interaction between measurement techniques and the problems to which they apply. However,
geodesy does not seem extraordinarily different from other environmentally oriented sciences in this respect and certainly
has been quick to adopt new techniques once the benefits become evident.” (NAS 1978, p. 6)
From the Keynote Address presented at Second International Symposium on Inertial Technology for Surveying and Geodesy, June
1–5, 1981, Banff, Alberta, Canada. 相似文献