Claire Digirolamo, NC State, Applications of GPOPS-II to Optimal Control Problems with Delays
ZoomChair: Stephen Campbell (steve slc@ncsu.edu, contact for Zoom access).
Chair: Stephen Campbell (steve slc@ncsu.edu, contact for Zoom access).
Chair: Mansoor Haider (mahaider@ncsu.edu, contact for Zoom access)
There will be our usual beginning of the semester meeting next Wednesday, August 12, at 4:15 p.m. The meeting will be held online. Departmental staff and faculty will receive a link.
Organizer: Seth Sullivant smsulli2@ncsu.edu
In this talk, we introduce a scattering asymmetry which measures the asymmetry of a domain on a surface by quantifying its incompatibility with an isometric circle action. We prove a quantitative isoperimetric inequality involving the scattering asymmetry and characterize the domains with vanishing scattering asymmetry by their rotational symmetry. We also give a new proof…
Organizer: Seth Sullivant smsulli2@ncsu.edu
The Turaev surface of a link diagram is a surface built from a cobordism between the all-A and all-B Kauffman states of the diagram. The Turaev surface can be seen as a Jones polynomial analogue of the Seifert surface. The Turaev genus of a link is the minimum genus of the Turaev surface for any…
The BBM equation is a nonlinear dispersive scalar PDE related to the KdV equation. However, it has a non-convex dispersion relation that introduces a variety of novel wave structures. These waves are highlighted by considering numerical solutions of Riemann problems, in which a smoothed step function initial condition u(x,0) exhibits long-time behavior that is a…
Organizer: Seth Sullivant smsulli2@ncsu.edu
Organizer: Seth Sullivant smsulli2@ncsu.edu
We will talk about the recent developments of the sign uncertainty principle and its relation with sphere packing and quadrature formulas. The talk will mainly be a report of the paper New Sign Uncertainty Principles, joint work with J. P. Ramos and D. Oliveira e Silva. Website: https://sites.google.com/view/paw-seminar Host: Paata Ivanisvili pivanis@ncsu.edu
Physics-informed neural networks (PINNs) have lately received great attention thanks to their flexibility in tackling a wide range of forward and inverse problems involving partial differential equations. However, despite their noticeable empirical success, little is known about how such constrained neural networks behave during their training via gradient descent. More importantly, even less is known…
Come chat with other geometers/topologists. This is a good chance for graduate students to meet the geometry/topology faculty, especially our newest members, Peter McGrath and Teemu Saksala. Host: Tye Lidman (tlid@math.ncsu.edu) Instructions to join: Zoom invitation is sent to the geometry and topology seminar list. If you are not on the list, please, contact the…
In this talk we review some classical algorithms for solving structured convex optimization problems, passing from gradient descent to proximal iterations and going further to modern proximal primal-dual splitting algorithms in the case of more complicated objective functions. We put special attention to constrained convex optimization, in which we accelerate the performance of the algorithms…
Organizer: Seth Sullivant smsulli2@ncsu.edu
We show that among nonnegative quadratic forms in n independent standard normal random variables, a diagonal form with equal coefficients maximizes differential entropy when variance is fixed. We also discuss some related open problems. Website: https://sites.google.com/view/paw-seminar Host: Paata Ivanisvili pivanis@ncsu.edu
We consider a geometric inverse problem of recovering some material parameters of an unknown elastic body by probing with elastic waves that scatter once inside the body. That is we send elastic waves from the boundary of an open bounded domain. The waves propagate inside the domain and scatter from an unknown point scatterer. We measure the entering…
Fluid-structure interaction (FSI) problems describe the dynamics of multi-physics systems that involve fluid and solid components. These are everyday phenomena in nature, and arise in various applications ranging from biomedicine to engineering. Mathematically, FSI problems are typically non-linear systems of partial differential equations (PDEs) of mixed hyperbolic-parabolic type, defined on time-changing domains. In this lecture…
Organizer: Seth Sullivant smsulli2@ncsu.edu