Highly-reduced dynamic orbits and their use for global gravity field recovery: A simulation study for GOCE

The so-called highly reduced-dynamic (HRD) orbit determination strategy and its use for the determination of the Earth’s gravitational field are analyzed. We discuss the functional model for the generation of HRD orbits, which are a compromise of the two extreme cases of dynamic and purely geometrically determined kinematic orbits. For gravity field recovery the energy integral approach is applied, which is based on the law of energy conservation in a closed system. The potential of HRD orbits for gravity field determination is studied in the frame of a simulated test environment based on a realistic GOCE orbit configuration. The results are analyzed, assessed, and compared with the respective reference solutions based on a kinematic orbit scenario. The main advantage of HRD orbits is the fact that they contain orbit velocity information, thus avoiding numerical differentiation on the orbit positions. The error characteristics are usually much smoother, and the computation of gravity field solutions is more efficient, because less densely sampled orbit information is sufficient. On the other hand, the main drawback of HRD orbits is that they contain external gravity field information, and thus yield the danger to obtain gravity field results which are biased towards this prior information.     

横波地震勘查技术在长春市活断层探测中的应用

以解决长春市区活断层的浅层地质问题为前提,阐述了活断层概念和横波的物理特征;从理论和实验的角度分析横波的分辨率和观测系统参数选取的原则.在试验的基础上,确定横波的观测系统,给出研究区的波组特征、断层分布和第四系的埋深情况.     

电感耦合等离子体发射光谱法同时测定碳酸盐岩石中19个元素

使用ＪＹ７０Ｐ 电感耦合等离子体发射光谱仪,分别考察了一些主要基体对待测元素的各种干扰。综合各种干扰因素,采用干扰系数校正法消除综合干扰,拟定了适用于包括碳酸盐岩石的区域化探样品中１９ 个元素的电感耦合等离子体原子发射光谱同时测定方法。１９ 个元素的测定限在０ ．２０ ～８ ．０ μｇ／ｇ 。对碳酸盐岩石国家一级标准物质ＧＢＷ０７１０８ 进行检测,各元素的结果与标准值吻合,相对标准偏差（ｎ ＝ １１） 在１ ．２ ％ ～５ ．３ ％ 。     

福建宁德三都澳海上钻探施工技术

通过总结福建省第四地质大队近年来三都澳海上钻探施工技术,阐述了海相沉积的各种较复杂地层的钻进工艺,以及海上钻探的导向护孔、跟管钻进、孔深丈量、安全设施等特种技术方法。     

圆形标志及其椭圆构像间中心偏差的确定

当目标面与像片平面不平行时,圆形标志的像将为椭圆,椭圆的中心与标志中心的像存在偏差。当标志较大时,此偏差将显著影响求解的精度。揭示了偏差的方向性,导出了求解偏差的方程,给出了偏差的解算步骤     

GPS卫星精密星历的实时确定

建立了一种GPS卫星实时轨道确定的新算法。该算法用法方程叠加方法更新卫星轨道参数,然后根据卫星轨道与卫星轨道参数之间的数值微分关系计算新的卫星轨道,并详细分析了用中国GPS跟踪网数据实时定轨的结果。     

MDD模式应用中若干问题的讨论Ⅱ——活化能选取的重要性

活化能取值在ＭＤＤ模式中对冷却曲线的温度有较大的影响,其影响度大约为７～８℃／ｋｃａｌ·ｍｏｌ－１,但它并不改变冷却曲线的形状。导致活化能取值偏低的影响因素包括低温阶段的加热时间、Ｋ－长石的纯度和部分斜长石、石英的混入等     

胶束增溶增敏分光光度法直接测定海水中的硼

首次以含量为１５ ％ 的非离子型乳化剂ＯＰ１００ 胶束体系为介质进行硼的分光光度法测定研究,确定最佳实验条件（ 最大吸收波长为５５５ｎｍ ,姜黄素用量为４ｍＬ,酸试剂用量为５ｍＬ,胶束用量为５ｍＬ,显色温度为５０ ℃,显色时间为１５ｍｉｎ） ,改进了现有的姜黄法,此方法适用于海水中硼的水相直接分光光度测定。实验结果表明测定灵敏度显著增加（Ｅ＝ １ ．５ ×１０５） ,线性范围变宽（０ ～１．２μｇ／２５ｍＬ） ,络合物稳定性好,稳定时间长达５０ｈ。     

轨道改进中计算状态转移矩阵的分析方法

对当今人卫轨道改进问题,由于力学模型的复杂,精密星历和状态转移矩阵的计算均采用数值方法,这就需要积分两组常微分方程．本文针对状态转移矩阵在定轨中的作用,对定轨弧段不太长的情况,给出了状态转移矩阵的一种分析算法,从而避免数值求解两组常微分方程的问题,并以实际算例证实了这种算法的有效性     

Strategy and Scenario for Radioastron Space VLBI Observations

Space VLBI's highly dynamic geometry, ability to access the space radio telescope (SRT) only via distant communication links, very expensive mission cost, and scientific goals define the basic strategy and scenario for mission control and radio source observations. These are very different from those for ground-based VLBI. Space VLBI strategy must be based on the limitation of SRT repointings, periodic orbit determination before astronomical observations, preliminary preparation and checking of space and ground facilities, and recommended observing sequences and modes. A control and observation scenario is considered for an in-orbit-checkout period, and also for short (1-orbit – 1 week) and long (1 week and more) observation sessions. Examples and illustrations are given for the Radioastron space VLBI Project.