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DOTs: Discrete Optimization Talks
https://talks.discreteopt.com/
A Virtual Seminar Series
By the Mixed Integer Programming Society
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We hope you join us for the next DOT session on Friday, October 9, 2026 at 12:00 ET (Sign up for zoom links).
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Speaker: Sonia Cafieri (ENAC)
Title:
Abstract: The Continuous Quadrant Penalty (CQP) approach provides a framework for addressing structured nonlinear optimization problems involving disjunctions. It relies on the introduction of a smooth, piecewise-quadratic penalty function, resulting in a continuous nonconvex optimization problem that provides a continuous-optimization alternative to classical mixed-integer formulations.
In this work, we address the sparse approximation problem. We propose an original CQP-based formulation and investigate its potential within a global optimization framework. Numerical experiments demonstrate the effectiveness of the proposed approach and highlight the potential of CQP formulations for solving sparse approximation problems.
Joint work with Marcel Mongeau
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Speaker: Thiago Serra (University of Iowa)
Title:
Abstract: When optimizing a nonlinear objective, one can employ a neural network as a surrogate for the nonlinear function. However, the resulting optimization model can be time-consuming to solve globally with exact methods. As a result, local search that exploits the neural-network structure has been employed to find good solutions within a reasonable time limit. For such methods, a lower per-iteration cost is advantageous when solving larger models. The contribution of this paper is two-fold. First, we propose a gradient-based algorithm with lower per-iteration cost than existing methods. Second, we further adapt this algorithm to exploit the piecewise-linear structure of neural networks that use Rectified Linear Units (ReLUs). In line with prior research, our methods become competitive with -- and then dominant over -- other local search methods as the optimization models become larger.
Joint work with Jiatai Tong (Northwestern), Yilin Zhu and Sam Burer (University of Iowa)
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Hope to see you there,
Margarita Castro (Pontificia Universidad Católica de Chile)
Silvia Di Gregorio (Université Sorbonne Paris Nord)
Aleksandr Kazachkov (University of Florida)
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For more information, including links to past talks, visit our website: https://talks.discreteopt.com. If you have any questions, email us at talks@discreteopt.com.