GPS水准在重力勘查中的应用

本文简要介绍了GPS水准的相关理论知识和野外点位测设的具体技术方法,并结合工程项目实例中的数据对比分析证明GPS水准点位高程精度完全满足重力测量要求。     

GPS网平面基准点的可靠性分析

通过具体实例，对GPS网约束平差结果进行了分析、比较，并提出了GPS网平面基准点的可靠性检验方法，得出了作为起算数据的基准点及其点位误差对GPS网约束平差精度的影响规律。     

联合GPS基准站和验潮站数据确定海平面绝对变化

采用中国地壳运动观测网络工程厦门基准站的GPS观测数据以及厦门验潮站的验潮数据,计算了厦门海域的海平面绝对变化速度,并就高程变化问题作了深入讨论,表明点位高程变化呈周期性,几期GPS连续观测受其影响不能得出实际的高程线性变化速率,指出了要监测验潮站的地壳垂直运动,最好采用多年连续的GPS观测数据。     

关于GPS网平面基准点的可靠性分析

通过具体实例，对GPS网约束平差结果进行分析、比较，并提出GPS网平面基准点的可靠性检验方法，得出作为起算数据的基准点，其点位误差对GPS网约束平差精度的影响规律。     

地壳形变GPS监测数据的统计分析研究

地壳形变与地震孕育有非常密切的关系,地壳形变监测可为地震预报提供重要的数据依据。本文论述了地壳形变和地震孕育的相互关系,对中国地壳运动观测网络的建立进行说明,并采用统计软件SPSS对区域网的GPS点位变化数据进行了统计分析,采用箱图的形式表示数据分析的结果,得到了统计数据中一些奇异点数据,这些点位数据需要进一步研究和探讨。     

基于GPS技术的大桥自振频率测量研究

以GPS快速静态相对定位技术对武汉白沙洲长江大桥进行自振频率测试,采用GPS动态监测的方法,通过对悬索桥关键点的点位测量和三维位移进行动态实时监测以及对测量数据的分析,得出点位时程图,经频谱分析得出长江三桥的自振特征要素。     

TEQC软件的应用与数据分析

介绍了点位数据质量检查工具TEQC软件及3种辅助绘图工具产生的历史背景、运行环境以及进行数据分析的方法和各自的优缺点;举例说明了TEQC软件对GPS数据进行转换、编辑与质量检查的步骤。结果表明,选择任意一种处理模式均可对点位数据进行质量分析。     

GPS网形与GPS网质量的关系分析

基于GPS静态相对测量,基线数据处理采用双差观测值单基线解算的一般模式,讨论GPS网基线解算和3维无约束平差的公式,得出GPS网的质量与基线向量质量和GPS网结构有关,而与网形和点位无关,并通过实验数据,分析验证了这一观点,提出了一些有益的结论。     

基于测量机器人的跨海三角高程自动测量系统

运用GEOCOM对测量机器人(TCA2003)进行二次开发,设计并研制了能够以GPS数据作为初始点位数据、设置自动完成多测回测量任务的适用于跨海高程传递的三角高程测量系统,通过相关试验,验证了该系统的准确性和自动化。     

粒子直线加速器精密三维控制网研究

提出利用激光跟踪仪建立精密三维控制网的具体方案,并对测量数据进行了相邻站拟合、边角重复测量统计等预处理。结果表明,相邻站数据拟合点位偏差在0.2 mm之内,距离重复测量精度为0.04 mm,水平角重复测量精度为2.48″,垂直角重复测量精度为3.92″。采用两种数据处理方法分别进行平面和高程平差,平面绝对点位精度0.08 mm,相对点位精度0.02 mm,高程点位精度0.06 mm,满足粒子加速器精密安装的要求。     

Pinpointing the sources and measuring the lengths of the principal rivers of the world

Abstract

Cultures throughout the world are associating with the rivers. People depend upon the rivers and their tributaries for food, water, transport, and many other aspects of their daily lives. Unfortunately, human beings have not calculated the accurate lengths for the great rivers even today. The lengths of the rivers are very different in popular textbooks, magazines, atlases and encyclopedias, etc. To accurately determine the lengths of the principal rivers of the world, the combination of satellite image analysis and field investigations to the source regions is proposed in this paper. The lengths of the Nile, Amazon, Yangtze, Mississippi, Yellow, Ob, Yenisey, Amur, Congo and Mekong, with lengths over or close to 5000 km, were calculated using the proposed method. The results may represent the most reliable and accurate lengths of the principal rivers of the world that are currently achievable.     

世纪之交的沉思--论21世纪软科学的发展

软科学这一术语是70年代在国外提出的.然而30多年以来,它在国外不仅未得到普遍的承认,而且对软科学的定义也还未能达成大体上一致的共识.而在改革开放后的中国,出于决策科学化和民主化的需要,经过一些领导人的提倡和支持,特别是通过1986年召开的软科学座谈会及1994年召开的全国软科学工作会议,软科学事业得到了蓬勃的发展.据初步统计,截止1998年底全国共有软科学研究机构1224个,研究人员32655人,初步形成了一支较为强大的研究队伍,并取得了数百项覆盖多个领域的研究成果,为支持各级各类的决策发挥了一定的作用.     

Improving the modeling of the atmospheric delay in the data analysis of the Intensive VLBI sessions and the impact on the UT1 estimates

The very long baseline interferometry (VLBI) Intensive sessions are typically 1-h and single-baseline VLBI sessions, specifically designed to yield low-latency estimates of UT1-UTC. In this work, we investigate what accuracy is obtained from these sessions and how it can be improved. In particular, we study the modeling of the troposphere in the data analysis. The impact of including external information on the zenith wet delays (ZWD) and tropospheric gradients from GPS or numerical weather prediction models is studied. Additionally, we test estimating tropospheric gradients in the data analysis, which is normally not done. To evaluate the results, we compared the UT1-UTC values from the Intensives to those from simultaneous 24-h VLBI session. Furthermore, we calculated length of day (LOD) estimates using the UT1-UTC values from consecutive Intensives and compared these to the LOD estimated by GPS. We find that there is not much benefit in using external ZWD; however, including external information on the gradients improves the agreement with the reference data. If gradients are estimated in the data analysis, and appropriate constraints are applied, the WRMS difference w.r.t. UT1-UTC from 24-h sessions is reduced by 5% and the WRMS difference w.r.t. the LOD from GPS by up to 12%. The best agreement between Intensives and the reference time series is obtained when using both external gradients from GPS and additionally estimating gradients in the data analysis.     

省直管市（县）体制下建设用地监管技术研究

面向解决省直体制下市（县）建设用地管理业务监管难度大问题,研究建设用地全过程监管关键技术,设计该模式下的监管模式、技术架构、业务模型和数据模型,实现省直管市（县）模式下的建设用地批前、批中、批后＂批-供-用-补-查-登＂全过程监管。     

Movements of the protoplanetary superconducting particles in the magnetic field of the Saturn lead to the origin of the rings

In this letter, we are trying to resolve the electromagnetic problem for the movements of the superconducting particles of the protoplanetary cloud in the magnetic field of Saturn. The force of levitation (Meissner-Ochsenfeld phenomenon) is introduced to the field of planetary science for the first time. It is shown from our theoretical analysis that rings of Saturn might have a superconducting origin, and rings might levitate within magnetic equator plane of the planet.     

国家一等水准网复测高程变化分析及其成果使用

分析国家一等水准网点复测高程的变化量值与分布特征以及导致高程变化的原因，对现有国家水准网点高程的使用提出建议。     

跟踪世界发展动态 致力地球重力场研究

比较系统、扼要地叙述了笔者所在单位40余年来坚持跟踪世界发展动态，致力于地球重力场理论和方法的研究，并从教学和生产需要出发，在地球重力场研究方面所获得的一些有理论意义和实用价值的成果。