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31.
The Tau Model for Data Redundancy and Information Combination in Earth Sciences: Theory and Application 总被引:3,自引:0,他引:3
Sunderrajan Krishnan 《Mathematical Geosciences》2008,40(6):705-727
Many decision-making processes in the Earth sciences require the combination of multiple data originating from diverse sources.
These data are often indirect and uncertain, and their combination would call for a probabilistic approach. These data are
also partially redundant with each other or with all others taken jointly. This overlap in information arises due to a variety
of reasons—because the data arises from the same geology, because they originate from the same location or the same measurement
device, etc. The proposed tau model combines partially redundant data, each taking the form of a prior probability for the
event being assessed to occur given that single datum. The parameters of that tau model measure the additional contribution
brought by any single datum over that of all previously considered data; they are data sequence-dependent and also data value-dependent.
Data redundancy depends on the sequence in which the data is considered and also on the data values themselves. However, for
a given sequence, averaging the tau model parameters over all possible data values leads to exact analytical expressions and
corresponding approximations and inference avenues. Information on multiple-point connectivity of permeability arrives from
core data, well-test data and seismic data which are defined over varying supports with complex redundancy between these information
sources. In order to compute these tau weights for determining connectivity, one needs a model of data redundancy, here expressed
as a vectorial training image (Ti) constructed using a prior conceptual knowledge of geology and the physics of data measurement.
From such a vectorial Ti, the tau weights can be computed exactly. Neglecting data redundancy leads to an over-compounding
of individual data information and the possible risk of making extreme decisions. 相似文献
32.
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: |
33.
lvaro Gonzlez Miguel Vzquez-Prada Javier B. Gmez Amalio F. Pacheco 《Tectonophysics》2006,424(3-4):319
Numerical models are starting to be used for determining the future behaviour of seismic faults and fault networks. Their final goal would be to forecast future large earthquakes. In order to use them for this task, it is necessary to synchronize each model with the current status of the actual fault or fault network it simulates (just as, for example, meteorologists synchronize their models with the atmosphere by incorporating current atmospheric data in them). However, lithospheric dynamics is largely unobservable: important parameters cannot (or can rarely) be measured in Nature. Earthquakes, though, provide indirect but measurable clues of the stress and strain status in the lithosphere, which should be helpful for the synchronization of the models.The rupture area is one of the measurable parameters of earthquakes. Here we explore how it can be used to at least synchronize fault models between themselves and forecast synthetic earthquakes. Our purpose here is to forecast synthetic earthquakes in a simple but stochastic (random) fault model. By imposing the rupture area of the synthetic earthquakes of this model on other models, the latter become partially synchronized with the first one. We use these partially synchronized models to successfully forecast most of the largest earthquakes generated by the first model. This forecasting strategy outperforms others that only take into account the earthquake series. Our results suggest that probably a good way to synchronize more detailed models with real faults is to force them to reproduce the sequence of previous earthquake ruptures on the faults. This hypothesis could be tested in the future with more detailed models and actual seismic data. 相似文献
34.
关于国土资源数据共享分类的思考 总被引:2,自引:0,他引:2
数据共享分类是制定数据共享政策和数据资源开发利用规划的一项基础性工作。本文 提出国土资源数据共享分类的意义、原则和方法,探讨建立以数据共享分类为核心的 国土资源数据分类体系,以期为全面开展国土资源数据共享分类提供参考。 相似文献
35.
三维遥感影像数据库系统的研究与实现 总被引:4,自引:0,他引:4
介绍了以3S技术为手段,采用目前较为先进的三层结构体系,使用Dephi开发工具,结合数据库技术、遥感技术,尝试以数据库SQL Server组织、存储、管理海量的中巴资源卫星遥感影像数据和新疆1:10万地形矢量数据,应用OpenGL技术实现海量三维遥感影像数据的三维立体显示浏览,进而完成全疆三维遥感影像库建库和三维显示及漫游. 相似文献
36.
伴随模式同化系统在修正模式地形中的应用 总被引:7,自引:1,他引:7
任何模式都只是实际大气的一种近似模拟,存在误差。鉴于传统的四维资料伴随模式同化系统都是假设模式完全正确仅对初始场进行修正。将伴随模式同化系统应用于修正模式地形误差,通过对不同初始地形的修正试验表明,MM5伴随模式同化系统能很好地对地形误差进行修正,能够反演出与初始气象要素场分辨率相匹配、与模式更协调的地形场,为伴随模式同化系统的广泛应用提供了一种新的思路。 相似文献
37.
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39.
利用DXF文件进行测量数据辅助处理 总被引:1,自引:0,他引:1
DXF文件是AUTOCAD与高级语言程序设计之间的接口文件,在测量工作中,充分利用DXF文件对测量数据进行辅助处理计算,可以达到事半功倍的效果. 相似文献
40.