Yao Lingqing, Dimitrakopoulos Roussos, Gamache Michel
Department of Mathematics and Industrial Engineering, Polytechnique Montréal, Montreal, QC H3T 1J4 Canada.
COSMO - Stochastic Mine Planning Laboratory, Department of Mining and Materials Engineering, McGill University, 3450 University Street, Montreal, QC H3A 2A7 Canada.
Math Geosci. 2020;52(5):693-723. doi: 10.1007/s11004-019-09843-3. Epub 2019 Dec 7.
The present work proposes a new high-order simulation framework based on statistical learning. The training data consist of the sample data together with a training image, and the learning target is the underlying random field model of spatial attributes of interest. The learning process attempts to find a model with expected high-order spatial statistics that coincide with those observed in the available data, while the learning problem is approached within the statistical learning framework in a reproducing kernel Hilbert space (RKHS). More specifically, the required RKHS is constructed via a spatial Legendre moment (SLM) reproducing kernel that systematically incorporates the high-order spatial statistics. The target distributions of the random field are mapped into the SLM-RKHS to start the learning process, where solutions of the random field model amount to solving a quadratic programming problem. Case studies with a known data set in different initial settings show that sequential simulation under the new framework reproduces the high-order spatial statistics of the available data and resolves the potential conflicts between the training image and the sample data. This is due to the characteristics of the spatial Legendre moment kernel and the generalization capability of the proposed statistical learning framework. A three-dimensional case study at a gold deposit shows practical aspects of the proposed method in real-life applications.
本研究提出了一种基于统计学习的新型高阶模拟框架。训练数据由样本数据和一幅训练图像组成,学习目标是感兴趣的空间属性的潜在随机场模型。学习过程试图找到一个具有与可用数据中观察到的高阶空间统计量一致的预期高阶空间统计量的模型,而学习问题是在再生核希尔伯特空间(RKHS)中的统计学习框架内解决的。更具体地说,所需的RKHS是通过系统地纳入高阶空间统计量的空间勒让德矩(SLM)再生核构建的。随机场的目标分布被映射到SLM-RKHS中以启动学习过程,其中随机场模型的解相当于解决一个二次规划问题。在不同初始设置下对已知数据集进行的案例研究表明,新框架下的顺序模拟再现了可用数据的高阶空间统计量,并解决了训练图像与样本数据之间的潜在冲突。这是由于空间勒让德矩核的特性和所提出的统计学习框架的泛化能力。在一个金矿床进行的三维案例研究展示了该方法在实际应用中的实际情况。