Bayesian data fusion in a spatial prediction context: a general formulation   总被引：1，自引：1，他引：1  

P. Bogaert  D. Fasbender 《Stochastic Environmental Research and Risk Assessment (SERRA)》2007,21(6):695-709

In spite of the exponential growth in the amount of data that one may expect to provide greater modeling and predictions opportunities, the number and diversity of sources over which this information is fragmented is growing at an even faster rate. As a consequence, there is real need for methods that aim at reconciling them inside an epistemically sound theoretical framework. In a statistical spatial prediction framework, classical methods are based on a multivariate approach of the problem, at the price of strong modeling hypotheses. Though new avenues have been recently opened by focusing on the integration of uncertain data sources, to the best of our knowledges there have been no systematic attemps to explicitly account for information redundancy through a data fusion procedure. Starting from the simple concept of measurement errors, this paper proposes an approach for integrating multiple information processing as a part of the prediction process itself through a Bayesian approach. A general formulation is first proposed for deriving the prediction distribution of a continuous variable of interest at unsampled locations using on more or less uncertain (soft) information at neighboring locations. The case of multiple information is then considered, with a Bayesian solution to the problem of fusing multiple information that are provided as separate conditional probability distributions. Well-known methods and results are derived as limit cases. The convenient hypothesis of conditional independence is discussed by the light of information theory and maximum entropy principle, and a methodology is suggested for the optimal selection of the most informative subset of information, if needed. Based on a synthetic case study, an application of the methodology is presented and discussed.  相似文献   

ALow-order　Model　of　Two-dimensional　Fluid　Dynamics　on　the　Surface　of　a　Sphere     

Mozheng Wei 《大气科学进展》1996,13(1):67-90

ＡＬｏｗ－ｏｒｄｅｒＭｏｄｅｌｏｆＴｗｏ－ｄｉｍｅｎｓｉｏｎａｌＦｌｕｉｄＤｙｎａｍｉｃｓｏｎｔｈｅＳｕｒｆａｃｅｏｆａＳｐｈｅｒｅＭｏｚｈｅｎｇＷｅｉ（ＣＲＣｆｏｒＳｏｕｔｈｅｒｎＨｅｍｉｓｐｈｅｒｅＭｅｔｅｏｒｏｌｏｇｙ，ＣＳＩＲＯＤｉｖｉｓｉｏ...  相似文献   

高温铀物种形成(Speciation)的热力学数据     

黄克玲  周鲁民  张景廉 《铀矿地质》1993,(6)

本文依据C.M.Criss和J.W.Cobble的“离子熵对应原理”,对1978年D.Langmuir给出的铀物种形成常温热力学数据进行了高温值的处理,得出了一套较全面而系统的高温热力学参数,以供参考使用。  相似文献   

一种基于人工免疫的图像分割算法     

汤凌  郑肇葆  虞欣 《测绘科技情报》2006,(3)

图像二维熵分割,一直因耗时长而限制了实际应用。本文借鉴生物免疫思想,提出二维熵图像分割的人工免疫算法。在克隆选择算法中引入疫苗的免疫接种,用于优化最优分割阈值对的搜索过程。在遥感高分辨率图像上的实验显示,该算法不仅能准确搜索到最优阈值对,而且计算时间只有传统算法的1.8%。该算法也验证了人工免疫思想用于图像分割的可行性和有效性。  相似文献   

MAXIMUM INFORMATION ENTROPY THEORY OF EFFLUENT BAND IN OPEN CHANNEL UNIFORM FLOW     

Ke Zhong HUANG  Tao JIANG 《国际泥沙研究》1998,(3)

ＭＡＸＩＭＵＭＩＮＦＯＲＭＡＴＩＯＮＥＮＴＲＯＰＹＴＨＥＯＲＹＯＦＥＦＦＬＵＥＮＴＢＡＮＤＩＮＯＰＥＮＣＨＡＮＮＥＬＵＮＩＦＯＲＭＦＬＯＷＫｅＺｈｏｎｇＨＵＡＮＧ１ａｎｄＴａｏＪＩＡＮＧ２ＡＢＳＴＲＡＣＴＴｈｅｐｒｉｎｃｉｐｌｅｏｆｍａｘｉｍｕｍ...  相似文献   

大气密度方程   总被引：4，自引：0，他引：4  

张学文 《气象学报》1998,56(3):377-382

通过一个思想实验把大气密度的时空分布函数与一个概率分布函数联系了起来,又利用最大熵原理导出了一个新的全球大气的方程,即大气密度方程。文章给出了它的通解并指出等温大气的压力高度公式是它的一个特解。对这个新的理论思路,新的方程和它的应用潜力作了初步讨论。  相似文献   

Natural entropy production in an inflationary model for a polarized vacuum     

Marcelo Samuel Berman  Murari M. Som 《Astrophysics and Space Science》2007,310(3-4):277-279

Though entropy production is forbidden in standard FRW Cosmology, Berman and Som presented a simple inflationary model where entropy production by bulk viscosity, during standard inflation without ad hoc pressure terms can be accommodated with Robertson–Walker’s metric, so the requirement that the early Universe be anisotropic is not essential in order to have entropy growth during inflationary phase, as we show. Entropy also grows due to shear viscosity, for the anisotropic case. The intrinsically inflationary metric that we propose can be thought of as defining a polarized vacuum, and leads directly to the desired effects without the need of introducing extra pressure terms.  相似文献   

1994年江淮地区首次区域性春季暴雨诊断分析     

王亦平  徐良谋  王肖成 《成都信息工程学院学报》1996,(4)

分析了１９９４年４月１９～２０日春季暴雨主要是由对流层中低层低涡和地面静止锋共同作用的结果，侧重于对低空急流的形成与变动和熵平衡方程的诊断分析，能量场与该次暴雨有很好的相关性  相似文献   

Capturing the essential spatial variability in distributed hydrological modelling: Infiltration parameters     

Nadim S. Farajalla  Baxter E. Vieux 《水文研究》1995,9(1):55-68

Selecting the correct resolution in distributed hydrological modelling at the watershed scale is essential in reducing scale-related errors. The work presented herein uses information content (entropy) to identify the resolution which captures the essential variability, at the watershed scale, of the infiltration parameters in the Green and Ampt infiltration equation. A soil map of the Little Washita watershed in south-west Oklahoma, USA was used to investigate the effects of grid cell resolution on the distributed modelling of infiltration. Soil-derived parameters and infiltration exhibit decreased entropy as resolutions become coarser. This is reflected in a decrease in the maximum entropy value for the reclassified/derived parameters vis a vis the original data. Moreover, the entropy curve, when plotted against resolution, shows two distinct segments: a constant section where no entropy was lost with decreasing resolution and another part which is characterized by a sharp decrease in entropy after a critical resolution of 1209 m is reached. This methodology offers a technique for assessing the largest cell size that captures the spatial variability of infiltration parameters for a particular basin. A geographical information system (GIS) based rainfall-runoff model is used to simulate storm hydrographs using infiltration parameter maps at different resolutions as inputs. Model results up to the critical resolution are reproducible and errors are small. However, at resolutions beyond the critical resolution the results are erratic with large errors. A major finding of this study is that a large resolution (1209 m for this basin) yields reproducible model results. When modelling a river basin using a distributed model, the resolution (grid cell size) can drastically affect the model results and calibration. The error structure attributable to grid cell resolution using entropy as a spatial variability measure is shown.  相似文献   

基于"一带一路"建设的环渤海地区港口优势评价          下载免费PDF全文

赵江南  周跃 《海洋开发与管理》2019,36(7):83-88

港口作为海陆运输的节点,是一个城市和国家的重要门户,对推动经济发展和对外贸易有着不可忽视的作用。基于国家提出的"一带一路"建设,评估环渤海港口的发展优势,逐步实现从沿海、沿江开放向内陆延伸具有重要意义。文章选取环渤海港口中的大连、天津、唐山、丹东、营口、锦州、秦皇岛、黄骅、日照、青岛、威海和烟台共12个港口进行发展优势对比。从港口吞吐量、港口规模范围、港口城市及腹地、港口未来发展4个方面构建环渤海港口优势评价体系。并利用熵权-TOPSIS法进行深入的实证分析。结果表明,环渤海港口群港口发展优势水平悬殊,基本可以分为4个档次。基于此,环渤海各港口应合理准确定位,通过错位发展和协同合作等方式谋求共赢。  相似文献