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排序方式: 共有751条查询结果,搜索用时 0 毫秒
1.
本文提出了一种把经纬度网格点上的气象要素值转化到正方形网格点上的多项式插值方案。对插值方案作了稳定性讨论和定量及定性分析。结果表明,这种插值方案方便可行,而且有广泛适用性。 相似文献
2.
This paper introduces a new method for GPS signal acquisition, which is based on the repeatability of successive code phase
measurements and the M-of-N search algorithm. The performance of the proposed method in terms of probability of signal detection
is similar to that of traditional methods, except that the calculation of the probability of detection does not rely on the
noise distribution or the Carrier-to-Noise ratio (C/N0). The code phase repeatability-based method is presented along with equations for probability of detection and probability
of false detection. If the distribution of the noise is known, it also provides an estimate of the C/N0. The proposed method is illustrated for coherent and non-coherent acquisition and C/N0 estimation. 相似文献
3.
Dynamic data integration for structural modeling: model screening approach using a distance-based model parameterization 总被引:2,自引:0,他引:2
This paper proposes a novel history-matching method where reservoir structure is inverted from dynamic fluid flow response.
The proposed workflow consists of searching for models that match production history from a large set of prior structural
model realizations. This prior set represents the reservoir structural uncertainty because of interpretation uncertainty on
seismic sections. To make such a search effective, we introduce a parameter space defined with a “similarity distance” for
accommodating this large set of realizations. The inverse solutions are found using a stochastic search method. Realistic
reservoir examples are presented to prove the applicability of the proposed method. 相似文献
4.
The advent of the Virtual Observatory has begun an evolution in the space physics data environment. A number of nascent and
discipline specific Virtual Observatories have started to emerge with an emphasis on data search and retrieval. As this new
data environment takes shape an emphasis will be placed on interdisciplinary communication in attempts to address large scale
and global problems. To this end we formulate the development of a query language to facilitate Virtual Observatory to Virtual
Observatory communication. Furthermore, we outline the goals of such a language, how it would work and how existing community
efforts can be leveraged to speed the development of this query language.
相似文献
T.W. NarockEmail: |
5.
Lars Kristian Nielsen Sam Subbey Mike Christie Trond Mannseth 《Computational Geosciences》2006,10(3):321-342
There is a correspondence between flow in a reservoir and large scale permeability trends. This correspondence can be derived by constraining reservoir models using observed production data. One of the challenges in deriving the permeability distribution of a field using production data involves determination of the scale of resolution of the permeability. The Adaptive Multiscale Estimation (AME) seeks to overcome the problems related to choosing the resolution of the permeability field by a dynamic parameterisation selection. The standard AME uses a gradient algorithm in solving several optimisation problems with increasing permeability resolution. This paper presents a hybrid algorithm which combines a gradient search and a stochastic algorithm to improve the robustness of the dynamic parameterisation selection. At low dimension, we use the stochastic algorithm to generate several optimised models. We use information from all these produced models to find new optimal refinements, and start out new optimisations with several unequally suggested parameterisations. At higher dimensions we change to a gradient-type optimiser, where the initial solution is chosen from the ensemble of models suggested by the stochastic algorithm. The selection is based on a predefined criterion. We demonstrate the robustness of the hybrid algorithm on sample synthetic cases, which most of them were considered insolvable using the standard AME algorithm. 相似文献
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基于网格的空间信息模型与服务技术研究 总被引:12,自引:0,他引:12
空间信息基础设施是实现数字城市的核心与基础,现有的万维网已经不能满足空间信息访问与处理的需要。该文对以空间信息为核心和基础的数据网格——空间信息网格的基础理论及网格中的空间信息模型与服务技术:进行研究。提出了空间信息网格的若干关键技术及网格中的空间信息模型的特点与要求,并对空间信息网格服务进行了初步的探讨。 相似文献
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讨论了根据影像匹配的结果将DSM修正成DTM的方法。本文针对城市地区航空影像的立体匹配结果,结合影像的结构纹理特征,提出了一种自动修正影像匹配结果以获得正确的DTM的方法。 相似文献