Calendar

Posted August 18, 2025
Last modified December 4, 2025

Control and Optimization Seminar Questions or comments?

Zequn Zheng, Louisiana State University
Generating Polynomial and Optimization-Based Algorithms for Tensor Decomposition

Tensors, or multidimensional arrays, are higher-order generalizations of matrices that naturally represent data with inherent multi-way structure. Tensor rank decomposition is a key tool for uncovering hidden patterns in such data. In this talk, we introduce a novel algorithm based on generating polynomials to compute tensor decompositions. We prove that under certain rank conditions, our method recovers the exact decomposition. For higher ranks beyond this threshold, we provide an optimization-based variant that effectively detects the tensor decomposition. Numerical experiments illustrate the robustness and efficiency of our approach.

Posted December 2, 2025

Combinatorics Seminar Questions or comments?

Kevin Grace, University of South Alabama
Matroid Adjoints, Minors, and Matrix Patterns

The notion of an adjoint of a matroid M arises from the attempt to attach a matroid to the lattice-theoretic dual of the lattice of flats of M. More precisely, a simple matroid M’, with the same rank as M, is an adjoint of M if there is an inclusion-reversing injective map from the lattice of flats of M into the lattice of flats of M’ that bijectively maps the hyperplanes of M onto the points of M’. Not all matroids have adjoints; however, in this talk, I will present a proof that the class of matroids that do have adjoints is minor-closed. If time permits, I will also discuss related work from the field of combinatorial matrix theory. In this related work, joint with Louis Deaett, we explore connections between the notion of an adjoint of a matroid and the minimum rank of matrices with a given zero-nonzero pattern.

Posted November 13, 2025
Last modified November 16, 2025

Colloquium Questions or comments?

Sean Cotner, University of Michigan
Propagating congruences in the local Langlands program

The Langlands program is a vast generalization of quadratic reciprocity, aimed at understanding the algebraic field extensions of the rational or p-adic numbers. In this talk, I will describe a biased and incomplete history of the classical local Langlands program; recent developments in making it categorical, integral, and modular; and joint work-in-progress with Tony Feng concerned with patching together the modular theory to understand the classical theory.

Posted July 22, 2025
Last modified December 4, 2025

Control and Optimization Seminar Questions or comments?

Javad Velni, Clemson University
Optimal Supplemental Lighting in Controlled Environment Agriculture: Data-driven and Model-based Perspectives

This seminar presents one aspect of my lab’s research focused on developing optimal supplemental lighting control strategies using LED lamps in controlled environment agriculture. The work aims to minimize electricity costs associated with supplemental lighting by integrating model-based optimization techniques with advanced machine learning methods, such as deep neural networks and Markov chains, used to predict uncertain environmental variables. Several scenarios are explored, ranging from a baseline optimal lighting approach for a single crop to more complex settings involving large-scale greenhouses with multiple crops and spatial light distribution considerations. Experimental results from a research greenhouse, where an Internet of Agricultural Things (IoAT) system was developed to grow lettuce, are presented and discussed. The seminar concludes with a roadmap highlighting several emerging research directions inspired by these findings.