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101.
机载激光测深中的波浪改正技术 总被引:3,自引:0,他引:3
基于我国新研制的机载激光测深系统基本配置,提出了3种可供选择的波浪改正计算方案(也称为深度值归算方案),具体分析了3种方案的适用条件和应用范围,并从理论上对3种改正模型的计算精度进行了估算。 相似文献
102.
一种新的多通道GPS共视资料的处理算法 总被引:2,自引:0,他引:2
提出了一种按仰角加权的多通道GPS共视资料处理算法,充分利用了所有观测数据,同时抑制了多径等因素影响,从而可提高共视比对精度。对日本邮政省通讯研究所(CRL)和国家授时中心(NTSC)2002年5月~2003年3月的多通道共视比对的处理结果表明,新的处理算法结果更接近真实钟差。 相似文献
103.
基于GPS基准站网的GPS测量 总被引:5,自引:0,他引:5
采用基于GPS基准网的GPS测量可以提高GPS测量的可靠性和准确性 ,可以消除和减小GPS测量观测值中与时间和空间相关的大气误差和轨道误差的影响 ,使中、长距离快速静态定位和RTK动态定位成为现实 ,还具有可直接得到WGS84Z坐标等优点。本文介绍基于GPS基准站网的GPS测量 ,简要地论述GPS虚拟参考站法VRS和区域改正数法FKP的原理、方法和特点 ,以及目前实施中存在的一些问题 相似文献
104.
内蒙古草原温室气体排放日变化规律研究 总被引:11,自引:0,他引:11
采用静态值-气相色谱法研究内蒙古草原温室气体N2O、CO2、CH4与大气交换的日变化规律。CO2日排放变化形式基本相同,和大气交换的总结果是向大气排放,影响草原N2O排放日变化形式的关键是土壤含水量和表层土壤理化特性,日温变化主要影响其日变化强度;影响草原CH4日变化形式的关键因子是土壤水分和供氧状况,而温度和植物的生长状况则影响吸收强度,利用内蒙古草原温室气候排放相对固定的日变化形式,可以对相同生产季内每周1次的观测结果进行矫正。 相似文献
105.
A new method is presented for the computation of the gravitational attraction of topographic masses when their height information is given on a regular grid. It is shown that the representation of the terrain relief by means of a bilinear surface not only offers a serious alternative to the polyhedra modeling, but also approaches even more smoothly the continuous reality. Inserting a bilinear approximation into the known scheme of deriving closed analytical expressions for the potential and its first-order derivatives for an arbitrarily shaped polyhedron leads to a one-dimensional integration with – apparently – no analytical solution. However, due to the high degree of smoothness of the integrand function, the numerical computation of this integral is very efficient. Numerical tests using synthetic data and a densely sampled digital terrain model in the Bavarian Alps prove that the new method is comparable to or even faster than a terrain modeling using polyhedra. 相似文献
106.
GPS与INSAR数据融合研究展望 总被引:9,自引:0,他引:9
分析了GPS与INSAR数据融合的必要性与可行性 ,讨论了GPS与INSAR数据融合存在的主要问题 ,进一步探讨了利用GPS数据改善INSAR相位解缠算法 ,利用GPS与INSAR数据融合建立水汽模型和大气层延迟误差改正模型 ,以及GPS高时间分辨率和高平面位置精度与INSAR高空间分辨率和高高程变形精度有效统一的问题。 相似文献
107.
108.
用差热和热(失)重法、pH值检验、离子色谱等分析方法考察和证实了Cl-对平菲尔特管重量法测定化合水(H2O+)的干扰,研究其影响规律,提出用系数校正方法可获得H2O+的准确结果。方法用于含氯深海沉积物和大洋多金属结核标准物质中H2O+的定值分析,取得满意结果 相似文献
109.
110.
A seismic re fraction/wide-angle reflection profile is analysed for the presence of correlated events ('phases'). The correlation problem is formulated in terms of temporally, spatially and frequency-local complex covariances. For robustness, the method concentrates on phase rather than amplitude information. This allows a computationally efficient algorithm that can make allowance for signal correlation length and can model curved wavefronts. A statistical test based on residual phase misfit across the analysed subarray is used to assess the probability that a detected event represents a real correlated signal.
With our chosen analysis parameters and confidence level (over 99.9 per cent). 1222 events were detected in the data. Using simple techniques based on 1-D earth models, detected events are associated with a small number of particular wave types. In this way, we have succeeded in classifying almost 95 per cent of the detected events. Those that remain describe those components of the data that are inconsistent with our simple ray paths in the 1-D assumption and with our prescribed tolerance. These include reverberations, near-surface guided waves and reflected waves from strongly laterally inhomogeneous structures. According to our modelling, about 25 per cent of the detected events are consistent with simple P -wave reflected energy, and these are to a very large extent (over 85 per cent) distinct from all the other wave-type models we have used. A direct mapping of the detected events into the offset-depth domain reveals dear internal and external consistencies among the detections for the various wave types. Estimated earth structure is consistent with models from previous analyses based on much larger data sets.
We have thus succeeded in extracting correlated events from the data and decomposing these, approximately but meaningfully, into distinct classes (ray paths) 相似文献
With our chosen analysis parameters and confidence level (over 99.9 per cent). 1222 events were detected in the data. Using simple techniques based on 1-D earth models, detected events are associated with a small number of particular wave types. In this way, we have succeeded in classifying almost 95 per cent of the detected events. Those that remain describe those components of the data that are inconsistent with our simple ray paths in the 1-D assumption and with our prescribed tolerance. These include reverberations, near-surface guided waves and reflected waves from strongly laterally inhomogeneous structures. According to our modelling, about 25 per cent of the detected events are consistent with simple P -wave reflected energy, and these are to a very large extent (over 85 per cent) distinct from all the other wave-type models we have used. A direct mapping of the detected events into the offset-depth domain reveals dear internal and external consistencies among the detections for the various wave types. Estimated earth structure is consistent with models from previous analyses based on much larger data sets.
We have thus succeeded in extracting correlated events from the data and decomposing these, approximately but meaningfully, into distinct classes (ray paths) 相似文献