Results 21 to 30 of about 20,099 (254)
Efficient simulation of Brown-Resnick processes based on variance reduction of Gaussian processes [PDF]
, 2018 Brown-Resnick processes are max-stable processes that are associated to Gaussian processes. Their simulation is often based on the corresponding spectral representation which is not unique.
Oesting, Marco, Strokorb, Kirstin
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Spatio-temporal mapping of salinity in the heterogeneous coastal aquifer
Applied Water Science, 2019 The interface between freshwater and saltwater in the coastal aquifer is a main factor that is affected by environmental threat and excessive pumping. In this study, a density-dependent numerical model was utilized to simulate the salt distribution of a ...
Ali Ranjbar, Majid Ehteshami
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Verification with Variograms [PDF]
Weather and Forecasting, 2009 Abstract The verification of a gridded forecast field, for example, one produced by numerical weather prediction (NWP) models, cannot be performed on a gridpoint-by-gridpoint basis; that type of approach would ignore the spatial structures present in both forecast and observation fields, leading to misinformative or noninformative ...
Caren Marzban, Scott Sandgathe
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Oil & Gas Science and Technology, 2020 For 3D geological modelling of oil and gas reservoirs, well pattern density is directly related to the number of samples involved in the calculation, which determines the variation function of stochastic modelling and has great impacts on the results of ...
Wang Jinkai +4 more
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Empirical variogram for achieving the best valid variogram
Communications for Statistical Applications and Methods, 2020 Modeling the statistical autocorrelations in spatial data is often achieved through the estimation of the variograms, where the selection of the appropriate valid variogram model, especially for small samples, is crucial for achieving precise spatial prediction results from kriging interpolations. To estimate such a variogram, we traditionally start by
Esam Mahdi +2 more
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Measuring galaxy segregation using the mark connection function [PDF]
, 2010 (abridged) The clustering properties of galaxies belonging to different luminosity ranges or having different morphological types are different. These characteristics or `marks' permit to understand the galaxy catalogs that carry all this information as ...
D. Stoyan +22 more
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Mathematics, 2021 Variogram models are a valuable tool used to analyze the variability of a time series; such variability usually entails a spherical or exponential behavior, and so, models based on such functions are commonly used to fit and explain a time series ...
Francisco Gerardo Benavides-Bravo +4 more
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Texture feature extraction of coal-rock image based on variogram and local variance image
Gong-kuang zidonghua, 2018 In view of problems of low classification accuracy and algorithmic running efficiency and poor robust property of rotation texture recognition existed in local binary patterns for texture feature extraction of coal-rock, a texture feature extraction ...
HUANG Lei, GUO Chaoya
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Mixed effect model for absolute log returns of ultra high frequency data [PDF]
, 2005 The influence of covariates on absolute log returns of ultra high frequency data is analysed. Therefore we construct a mixed effect model for the absolute log returns. The parameters are estimated in a state space approach.
Czado, Claudia, Haug, Stephan
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Generalized product-sum variogram models of the data of the Center of Marine Research
Lietuvos Matematikos Rinkinys, 2004 Environmental data usually depends on both spatial and temporal components. Therefore, it is essential to have statistical models to describe how the data vary across space and time.
Ingrida Krūminienė +1 more
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