Events Calendar

Astani CEE Dept. Seminar

Speaker: Christine Shoemaker, Joseph P. Ripley Professor, School of Civil and Environmental Engineering &Cornell University

Talk Title: Optimization of Computationally Expensive Environmental Models Including Application to Monitoring Multi-Phase Subsurface flow from Carbon Sequestration

Abstract: This talk will first give an overview of my research on optimization and uncertainty quantification and its application to a range of environmental topics. Our new algorithms (available as open source software) are very efficient for these applications and other multi-modal, computationally expensive simulation models because the algorithms are designed to reduce significantly the number of simulations required for finding the global optimal solution to a problem with multiple local minima. Our approach is to iteratively approximate the objective function or likelihood function f(x) with Radial Basis Functions (RBF) based on all previous simulations to guide the selection of the next expensive function evaluation. The applications incorporate issues related to monitoring, forecasting, uncertainty quantification, and risk analysis as well parameter estimation and design.

Estimation of sequestered CO2 and pressure plumes is very important for risk analysis but difficult because the multiphase PDE model is very nonlinear and computationally expensive, monitoring data is very sparse, and the inverse optimization problem has multiple local minima. Each objective function evaluation requires expensive forward simulation of 3-D, highly nonlinear, multi-phase, multi-constituent set of PDEs (which can take hours per simulation). I’ll present results using TOUGH2 that give good current estimates and forecasts of plumes with our global optimization algorithm Stochastic RBF with a small number of original model simulations, and I’ll use our SOARS algorithm to assess uncertainty.


Biography: Prof. Shoemaker received a PhD in Mathematics from USC supervised by Richard Bellman on dynamic programming and control. She is interested in surface and subsurface contaminant transport applications as well as in developing new computationally efficient distributed (HPC) optimization and control methods. Environmental topics she has worked on include watershed contaminant transport, groundwater remediation, global climate models (CLM4.5) and optimization of stochastic hydropower systems (BPA). . She is a member of the National Academy of Engineering and a Distinguished Member in ASCE. She is also a Fellow in INFORMS (Operations Research) and in AGU (hydrology).

Host: Astani CEE Dept.

Location: Kaprielian Hall (KAP) - 209

Audiences: Everyone Is Invited

Contact: Cassie Cremeans