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81.
空间软数据及其插值方法研究进展 总被引:7,自引:0,他引:7
由于对地观测技术的迅速发展,空间数据的种类和数量增长迅猛,由空间数据反演得到的各种信息日趋膨胀,这些反演结果中的信息不少以软数据的形式出现。在实际应用中,这些软数据往往与空间插值的目标变量具有一定的相关性,甚至成为控制目标变量空间分布特征的重要因素。然而,由于这些数据通常表示为非数值形式,在计算和处理上存在着一定困难,以致被传统的插值方法所忽视,从而造成信息浪费。近来出现的空间软插值方法是一种利用空间软数据作为辅助信息并以改善插值效果的方法,能够较好的处理并利用软数据所隐含的信息,具有较好的应用发展前景。本文根据空间软数据的特点及其分类,系统综述了空间软插值方法及其应用领域。首先分析了空间数据软硬性质的根本区别,论述了软数据的分类和“硬化”方法,然后介绍空间插值模型中对空间软数据的集成方法和原理,最后对空间软插值方法及其应用研究领域进行了展望。 相似文献
82.
Theoretical difficulties for mapping and for estimating river regime characteristics in a large-scale basin remain because of the nature of the variable under study: river flows are related to a specific area, i.e. the drainage basin, and are hierarchically organized in space through the river network with upstream-downstream dependencies. Another limitation is there are not enough gauge stations in developing countries. This presentation aims at de-veloping the hydro-stochastic approach for producing choropleth maps of average annual runoff and computing mean discharge along the main river network for a large-scale basin. The approach applied to mean annual runoff is based on geostatistical interpolation proce-dures coupled with water balance and data uncertainty analyses. It is proved by an applica-tion in the upstream at Bengbu in the Huaihe River Basin, a typical large-scale basin in China. Hydro-stochasitic approach in a first step interpolates to a regular grid net and in a second step the grid values are integrated along rivers. The interpolation scheme includes a con-straint to be able to account for the lateral water balance along the rivers. Grid runoff map with 10 km × 10 km resolution and the discharge map along the river with the 1 km basic length unit are the main results in this study. This kind of statistic approach can be widely used be-cause it avoids the complexity of hydrological models and does not depend on the meteoro-logical data. 相似文献
83.
黄龙的景观是在数万年的岩溶地质作用下的产物。近年来黄龙钙华出现了干涸、变黑、沙化等现象严重地影响了景观的观赏性。水资源在黄龙钙华发展变化中起着重要的作用,笔者通过收集并分析黄龙地区的监测数据,针对监测系统不健全.时序数据缺乏的特点,选用对时序数据要求不高、预测效果较好的灰色系统模型,以岩溶水体的pH值为指标预测了钙华未来的发展情况。采用地质统计学空间分析的克里金插值法,对预测结果进行插值获得了整个景区的钙华预测结果。笔者按pH值将钙华演化情况划为强侵蚀、弱侵蚀、堆积3种类型,指出黄龙钙华景观目前正处于动态平衡与消亡重组阶段。 相似文献
84.
85.
A. G. Journel 《Mathematical Geology》1988,20(4):459-475
The projection or minimum error norm algorithm does not require that the distance measure be a variogram. In non-Gaussian cases, the traditional variogram distance measure leading to minimization of an error variance offers no definite advantage. Other distance measures, more outlierresistant than the variogram, are proposed which fulfill the condition of the projection theorem. The resulting minimum error norms provide the same data configurations ranking as traditionally obtained from kriging variances. A case study based on actual digital terrain data is presented.This paper was presented by title at MGUS 87 Conference, Redwood City, California, 14 April 1987. 相似文献
86.
Common features of models for interpolation, consistent with a finite number of inequality constraints on the range of values of a variablez, are discussed. A method based on constrained quadratic minimization yielding kriging estimates when no constraints exist, is presented. A computationally efficient formulation of quadratic minimization is obtained by using results on duality in quadratic programming. Relevant properties of the optimal interpolator are derived in a simple, self-contained way. The method is applied to mapping of horizon depth and estimation of thickness of an oil-bearing formation. 相似文献
87.
Parametric time domain time series models for different chemical constituents such as SiO
2,Fe
2
O
3,TiO
2,MnO, and P
2
O
5
of iron ores belonging to banded hematite quartzites in Bicholim Mine (Goa) have been utilized for forecasting Fe
2
O
3
assay values through single/multiple input—single output (Fe
2
O
3
) transfer function with noise methodology. Statistically significant correlated chemical constituent inputs (say, SiO
2,TiO
2,MnO, P
2
O
5
) along lateral (horizontal strike direction) and vertical (perpendicular to bedding planes) sections in this mine are useful in modeling as well as forecasting assay values of blocks of ore to be exploited. Parameters of transfer function—noise models are estimated by utilizing time domain methodology, and the usefulness of these models for optimization of mining operations is discussed. 相似文献
88.
Geological data frequently have a heavy-tailed normal-in-the-middle distribution, which gives rise to grade distributions that appear to be normal except for the occurrence of a few outliers. This same situation also applies to log-transformed data to which lognormal kriging is to be applied. For such data, linear kriging is nonrobust in that (1)kriged estimates tend to infinity as the outliers do, and (2)it is also not minimum mean squared error. The more general nonlinear method of disjunctive kriging is even more nonrobust, computationally more laborious, and in the end need not produce better practical answers. We propose a robust kriging method for such nearly normal data based on linear kriging of an editing of the data. It is little more laborious than conventional linear kriging and, used in conjunction with a robust estimator of the variogram, provides good protection against the effects of data outliers. The method is also applicable to time series analysis. 相似文献
89.
This short note establishes the equivalence between trend surface analysis with polynomials of orderk and IRF-k (intrinsic random function of orderk) kriging with a nugget effect covariance model. 相似文献
90.
The problem of estimating the proportion of lithological (ore) types in volumes of mineral deposits is considered when an auxiliary variable Z(z) is observed along with the lithology L(x) at x. The process {Z(x)} is assumed to be stationary and an assumption on the statistical relationship between {Z(x)} and {L(x)} processes is made. Consequently, the second-order stationarity of {L(x)} is not required. A method using the kriged distribution of the auxiliary variable is proposed. A case study illustrating the procedure is given. 相似文献