共查询到19条相似文献,搜索用时 140 毫秒
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为了提高多系统组合单点定位的运算效率,将Bancroft算法推广应用于GPS/BDS/GLONASS三系统伪距单点定位,并推导了该方法的详细计算流程,比较了Bancroft算法、最小二乘算法和组合两种算法的精度、迭代次数以及运算时间。利用实测数据进行实验,结果表明,3种算法精度相当,Bancroft算法比最小二乘算法迭代次数少,运算效率提高了38%,利用Bancroft为最小二乘算法提供初值,收敛速度加快,运算效率提高了36%。最终得出结论,Bancroft算法应用于GPS/BDS/GLONASS三系统伪距单点定位满足精度要求,且Bancroft算法对于减少迭代次数,提高运算效率有重要意义。 相似文献
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美国海军海洋局实施海道测量,测量船的位置是应用参数变化平差法确定的。测量船使用三种类型的导航定位设备;测距的、测角的和双曲线的。参数变化平差法定位就是,先由任意两类导航定位设备给出观测数据,再用逐次平差法求得最或是位置。每次平差值的大小及方向均由最小二乘法确定,即实际导航定位设备的观测结果与假定船在近似位置计算出的结果(假定观测结果)之残差为最小。 相似文献
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数字高程模型(DEM)是描述地表起伏形态特征的空间数据模型。DEM完全可以代替传统使用等高线对地形表面的描述,进而满足对等高线数据相同的各种需求。内插是DEM的核心问题,它是DEM各种应用的基础。介绍了加权最小二乘曲面拟合法构建规则格网DEM的理论和方法。试验结果表明:加权最小二乘曲面拟合算法具有插值结果较精确、处理效率较高和模拟地表效果较好等优点。 相似文献
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空间任意多元声阵列无源定位研究 总被引:1,自引:0,他引:1
针对平面多元声阵列在被动定位和实际应用中存在的问题,提出全空间任意多元阵列定位统一模型,并利用最小二乘法和迭代法求解目标位置参数,同时分析了影响该模型定位精度的几种主要因素.数值仿真和试验结果表明,该算法可实现较高精度的目标定位,且阵列布设简单. 相似文献
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不规则重磁测线网误差模型的约束最小二乘平差 总被引:5,自引:1,他引:5
传统实用的海洋重力、磁力测线网平差方法主要为规则测线网设计,并只就线偏差进行调整,用于处理航次数据之间的拼接时效果不理想。为了解决重磁测线数据拼接和建库工作中碰到的误差难以调平的问题,设计、建立了不规则海洋重磁测线网的任意复杂误差模型的最小二乘平差方法,将线偏差纳入到任意复杂(如非线性和周期性)的误差模型中,归纳出最小二乘条件方程系数矩阵的直接构制法。针对可能出现的解不稳定,放弃不易实用的权矩阵,引入两种解决方法:先验确定部分测线误差分布的固定测线法和视误差大小实施系数矩阵对角线微扰动的泛约束法。 相似文献
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提出6种少量地面重力测量布设方案和4种基于少量地面控制的航空重力测量数据处理方法,建立基于最小二乘配置的格网平均重力异常的融合模型,有效地估计出了航空重力数据可能存在的系统偏差,提高了格网数据的质量。 相似文献
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林俊轩 《中国海洋大学学报(自然科学版)》1996,(4)
采用场匹配处理法反演层系介质参数,在匹配处理前先对层系模型参数进行预估。参数预估将大大地减少匹配运算时间。模拟实验的反演结果与取样实测结果相当符合 相似文献
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In a series of attempts to research and document relevant sloshing type phenomena, a series of experiments have been conducted. The aim of this paper is to describe the setup and data processing of such experiments. A sloshing tank is subjected to angular motion. As a result pressure registers are obtained at several locations, together with the motion data, torque and a collection of image and video information. The experimental rig and the data acquisition systems are described. Useful information for experimental sloshing research practitioners is provided. This information is related to the liquids used in the experiments, the dying techniques, tank building processes, synchronization of acquisition systems, etc. A new procedure for reconstructing experimental data, that takes into account experimental uncertainties, is presented. This procedure is based on a least squares spline approximation of the data. Based on a deterministic approach to the first sloshing wave impact event in a sloshing experiment, an uncertainty analysis procedure of the associated first pressure peak value is described. 相似文献
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本文首先介绍了由中国科学院上海技术物理研究所最新研制的海洋多波段扫描仪(OMS)的性能和特色,并描述了1999年10月份在黄渤海典型海区进行航空校飞的实验的概况及校飞资料的处理过程。然后,针对不同海区的水色特点,着重探讨了通过最佳通道选择进行假彩色合成叶绿素的定性提取法和模式计算的定量提取法的原理和方法。最后,通过航空校飞、卫星遥感和实测三种准同步资料所得叶绿素浓度空间分布的趋势比较验证了两种叶绿素提取方法和可信度,同时也显示了在OMS基础上所研制的我国第一颗海洋水色卫星水色遥感器的应用前景。 相似文献
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The magnetostratigraphy of sediments drilled at two sites (998 and 1001) in the Caribbean Sea during the Ocean Drilling Program (ODP) Leg 165 is established directly from downhole measurements. For the first time in the ODP, the magnetostratigraphy of sediments is determined from both logging magnetic data and paleomagnetic analysis of core material for an age interval of about 16 m.y. across the Cretaceous/Tertiary boundary. The total magnetic induction and the susceptibility of the surrounding sediment were recorded in situ and continuously by the GHMT (Geological High-sensitivity Magnetic Tool). The aim of processing these data is to determine the magnetic polarity. At Site 998 (Cayman Rise), no paleomagnetic results are available from the recovered cores given a hard secondary overprint. Nonetheless, a magnetostratigraphic sequence from early Miocene to late Oligocene is proposed from the analysis of the GHMT data. The comparison with biostratigraphic results shows the accuracy of the resulting magnetic polarity. At Site 1001 (Hess escarpment), cores were recovered in two holes thus allowing the comparison of the magnetostratigraphic results obtained from the GHMT data and from paleomagnetic analysis of core samples over a length of 200 m representing about 16 m.y. from early Eocene to late Cretaceous times. The sedimentation rates computed from the determined magnetochrons are very similar and correspond to the ones obtained from shipboard biostratigraphic results. One of the most striking result obtained from the magnetostratigraphic results, especially the GHMT data, at Site 1001, is the abrupt decrease in the sedimentation rate across the K/T boundary. This suppressed sedimentation lasted at least 4 Ma after the K/T event. 相似文献
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A. S. Vasilyev 《Physical Oceanography》1996,7(6):445-454
The paper considers the statement of the problem on quasi-stationary diagnosis of currents, temperature, salinity, and density
fields for multiply connected areas with fluid boundaries. The principles of self-similar parameterization over the vertical
axis are applied by introducing models for the vertical substance distribution, which have two regularly varying functions.
The problem is reduced to handling a set of Poisson equations, enabling the boundary conditions to be automatically determined
at the island shores. A scheme is presented for calculating current velocity components at an arbitrarily oriented transect.
Several examples of current velocity computation for the topographically complex oceanic areas are given which support the
data collectedin situ.
Translated by Vladimir A. Puchkin. 相似文献
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