Surfer 8.0在GPS实时监控系统公路碾压试验中的应用

利用Surfer 8.0提供的Kriging插值法,对GPS在公路碾压施工中采集的同一仓面不同高程面的三组数据格网化,分别绘制了三组试验的等值线分布图和层厚三维图,并对其误差进行了分析,说明了该软件在试验中应用的可行性。     

SRTM高程数据中空缺单元的内插填补

简要介绍了SRTM生产的数字高程数据,认为采用直接内插来填补其中的空缺数据是最为简便的方法,以加权平均水平面移动拟合法为例,详细阐述了空缺单元的内插计算方法和基本过程,讨论比较了不同条件下的效果,认为SRTM的数字高程数据具有非常广泛的用途和前景。     

SOFTWARE REVIEWS

Electromap World Atlas , Version 1.1. Interactive Population Statistical System , Version 1.0. Jerry W. Wicks and Jose Luiz Pereira de Almeida MATHCAD , Version 2.5. Memory Mate. Micro DEM +, Version 5.21. Peter Guth NCSS – Number Cruncher Statistical System , Version 5.02. Dr. Jerry L. Hintze     

Triangle based interpolation

Triangle based interpolation is introduced by an outline of two classical planar interpolation methods, viz. linear triangular facets and proximal polygons. These are shown to have opposite local bias. By applying cross products of triangles to obtain local gradients, a method designated slant-top proximal polygon interpolation is introduced that is intermediate between linear facets and polygonal interpolation in its local bias. This surface is not continuous, but, by extending and weighting the gradient planes, a C¹ surface can be obtained. The gradients also allow a roughness index to be calculated for each data point in the set. This index is used to control the shape of a blending function that provides a weighted combination of the gradient planes and linear interpolation. This results in a curvilinear, C¹,interpolation of the data set that is bounded by the linear interpolation and the weighted gradient planes and is tangent to the slant-top interpolation at the data points. These procedures may be applied to data with two, three, or four independent variables.     

基于多面核函数配置型模型的参数估计

针对同时出现非随机参数、已测点和未测点信号的配置型模型精确建立协方差函数的困难，在研究和应用最小二乘配置和多面函数拟合法的基础上，将两法综合，提出了多面核函数配置法，导出了这种平差方法的解算公式。并与最小二乘配置、多面函数拟合作了比较分析。     

一种顾及地形特征的DEM内插方法

Delaunay三角网是表示地形的一种常用方法 ,在DEM内插中也有着广泛的应用。文中利用自适应分块技术进行Delaunay三角网的快速构建 ,实现了基于Delaunay三角网的DEM规则格网快速内插 ,内插结果能较好地顾及地形特征且反应地表的真实形态     

多面函数拟合法及其在建立中国地壳平面运动速度场模型中的应用研究

基于现有的GPS观测值，将多面函数拟合法用于速度场模型的建立，得到了目前中国覆盖范围最广、分布最均匀、有实用价值的中国地壳平面运动整体速度场图像和NNR－NUVEL1A全球板块运动模型下的平面运动速度场图像。     

Solution of dynamic response of SDOF system using piecewise Lagrange polynomial

As an extension of the procedure in which an arbitrary dynamic loading is approximated by piecewise linear segments, the second‐ and third‐degree piecewise Lagrangian interpolating polynomials are employed to approximate an arbitrary dynamic loading in the Duhamel integral for the solution of dynamic response of a SDOF system. The related formulae are derived. The proposed method offers computational advantage over the traditional step‐by‐step solution techniques for comparable accuracy, and far better accuracy than the piecewise linear approximation procedure for comparable time interval when the loading cannot be represented by straight‐line segments. Copyright © 2001 John Wiley & Sons, Ltd.     

广州市GPS控制网的设计特色和技术要点

介绍了广州市GPS控制网的设计特色、技术要点和实际效果，该控制网的实践对大型控制网布测具有一定的指导作用。     

利用数值预报产品制作夏季降水分县分级预报试验

将国家气象中心Ｔ６３和ＨＬＡＦＳ，武汉区域中心ＭＡＰＳ数值预报模式的短期降水预报分别以所属７个测站上，以此作为预报因子，运用灰色预测ＧＭ（Ｏ，ｈ）模型制作 孝感市夏季短期２４小时降水分县分级预报。经１９９６年夏季业务应用，其一般性降水（小雨、中雨、大雨）分县预报质量较高、暴雨落区落占预报能力较中，取得了良好的预报效果。