nonlinear semi-infinite programming solver
Development of the NSIPS software package.

process modeling and optimization in wastewater treatment plants
WWTP optimal design is an interdisciplinary area requiring mathematicians and chemical and biological engineering expertise. Poor regions in the North of Portugal need effective Wastewater Treatment Plant (WWTP) proposals with reduced installation and operation costs. In this project, we propose to address the problem of modeling WWTP unitary processes in the most efficient and economic manner. To conduct this study, a detailed and efficient analysis of the existing models is required.
Most of the previous experiences concerning WWTP optimal design rely on simulation methodologies. Mainly, they find the best combination of the design variables in order to achieve the minimum cost, choosing one among some possible designs. Following an optimization point of view, this project aims to define a set of equality and inequality constraints, which come from WWTP unitary processes modeling, mass and flow balances, and operational conditions, and a cost function that reflects investment and operational costs, so that we obtain an optimization problem that describes with detail and accuracy a WWTP, aiming to minimize costs.

solving large-scale integer programs
This project aims to solve large-scale integer programs combining penalty techniques based on exponential functions, the volume algorithm and heuristics.