Applications – Science and Engineering

Nonlinear Model Predictive Control with an Infinite Horizon Approximation

  • Lorenz T. Biegler
    • Categories Chemical Engineering, Control Applications, Nonlinear Optimization Tags , , , ,

    Current nonlinear model predictive control (NMPC) strategies are formulated as finite predictive horizon nonlinear programs (NLPs), which maintain NMPC stability and recursive feasibility through the construction of terminal cost functions and/or terminal constraints. However, computing these terminal properties may pose formidable challenges with a fixed horizon, particularly in the context of nonlinear dynamic processes. Motivated … Read more

    Combining Simulation with Machine Learning and Optimization to Assess Green Hydrogen Production via Offshore Wind in the Dutch North Sea

  • Justin Starreveld
  • Dick den Hertog
  • Kenneth Bruninx
  • Alessandro Bianchini
  • Riccardo Travaglini
  • R.J van 't Veer
  • Laurens Frowijn
    • Categories Applications - OR and Management Sciences, Energy, Optimization of Simulated Systems Tags , , ,

    As countries seek to decarbonize their energy systems, green hydrogen has emerged as a promising energy carrier. This paper studies the production of green hydrogen from offshore wind in the Dutch North Sea, with particular emphasis on understanding how system design decisions and uncertain parameters affect key performance indicators. The analysis builds on a detailed … Read more

    Integrated Bus Fleet Electrification Planning Through Accelerated Logic-Based Benders Decomposition and Restriction Heuristics

  • Robin Legault
  • Filipe Cabral
  • Xu Andy Sun
    • Categories (Mixed) Integer Linear Programming, Facility Planning and Design, Transportation Tags , ,

    To meet sustainability goals and regulatory requirements, transit agencies worldwide are planning partial and complete transitions to electric bus fleets. This paper presents the first comprehensive and computationally efficient multi-period optimization framework integrating the key planning decisions necessary to support such electrification initiatives. Our model, formulated as a two-stage integer program with integer subproblems, jointly … Read more

    Collection points placement in urban delivery: A game-theoretic analysis of public and competitive strategies

  • Fabio Mercurio
  • Margarida Carvalho
  • S.U.K Rohmer
  • Loe Schlicher
  • Tom Van Woensel
    • Categories Facility Planning and Design, Game Theory Tags , , , ,

    Collection point networks are rapidly expanding as delivery companies and public authorities promote their implementation to consolidate deliveries and reduce urban congestion. However, rather than catering to public interest by maximizing accessibility, the placement of collection points remains primarily driven by competition among delivery companies, which seek to maximize their market share. This paper thus … Read more

    Constrained Enumeration of Lucky Tickets: Prime Digits, Uniqueness, and Greedy Heuristics

  • Bismark Singh
    • Categories Basic Sciences Applications, Optimization in Data Science

    We revisit the classical Lucky Ticket (LT) enumeration problem, in which an even-digit number is called lucky if the sum of the digits of its first half equals to that of its second half. We introduce two new subclasses — SuperLucky Tickets (SLTs), where all digits are distinct, and LuckyPrime Tickets (LPTs), where all digits … Read more

    Preconditioning for rational approximation

  • Nadezda Sukhorukova
    • Categories Generalized Convexity/Monoticity, Nonsmooth Optimization, Optimization of Systems modeled by PDEs Tags , , ,

    In this paper, we show that minimax rational approximations can be enhanced by introducing a controlling parameter on the denominator of the rational function. This is implemented by adding a small set of linear constraints to the underlying optimization problem. The modification integrates naturally into approximation models formulated as linear programming problems. We demonstrate our … Read more

    Novel closed-loop controllers for fractional linear quadratic tracking systems

  • Malmir Iman
    • Categories Applications - Science and Engineering, Approximation Algorithms, Systems governed by Differential Equations Optimization Tags , , , , ,

    A new method for finding closed-loop optimal controllers of fractional tracking quadratic optimal control problems is introduced. The optimality conditions for the fractional optimal control problem are obtained. Illustrative examples are presented to show the applicability and capabilities of the method. ArticleDownload View PDF

    A Dynamic Strategic Plan for Transition to Campus-Scale Clean Electricity Using Multi-Stage Stochastic Programming

  • Ahmet Emir Şener
  • Burak Kocuk
  • Tuğçe Yüksel
    • Categories Energy, Stochastic Programming Tags , , ,

    The decarbonization of energy systems at energy-intensive sites is an essential component of global climate mitigation, yet such transitions involve substantial capital requirements, ongoing technological progress, and the operational complexities of renewable integration. This study presents a dynamic strategic planning framework that applies multi-stage stochastic programming to guide clean electricity transitions at the campus level. … Read more

    Two approaches to piecewise affine approximation

  • Nadezda Sukhorukova
    • Categories Applications - OR and Management Sciences, Approximation Algorithms, Data-Mining Tags , , ,

    The problem of approximation by piecewise affine functions has been studied for several decades (least squares and uniform approximation). If the location of switches from one affine piece to another (knots for univariate approximation) is known the problem is convex and there are several approaches to solve this problem. If the location of such switches … Read more

    Algorithmic Approaches for Identifying the Trade-off between Pessimism and Optimism in a Stochastic Fixed Charge Facility Location Problem

  • Man Yiu Tsang
  • Karmel S. Shehadeh
    • Categories Facility Planning and Design, Robust Optimization, Stochastic Programming Tags , , ,

    We introduce new algorithms to identify the trade-off (TRO) between adopting a distributional belief and hedging against ambiguity when modeling uncertainty in a capacitated fixed charge facility location problem (CFLP). We first formulate a TRO model for the CFLP (TRO-CFLP), which determines the number of facilities to open by minimizing the fixed establishment cost and … Read more