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Rossana Capuani, NC State, Mean field games with state constraints

SAS 4201

This talk will address deterministic mean field games for which agents are restricted in a closed domain of R^n with smooth boundary. In this case, the existence and uniqueness of Nash equilibria cannot be deduced as for unrestricted state space because, for a large set of initial conditions, the uniqueness of solutions to the minimization…

Pedro Aceves Sanchez, NC State, Fractional diffusion limit of a linear kinetic transport equation in a bounded domain

SAS 4201

In recent years, the study of evolution equations featuring a fractional Laplacian has received much attention due to the fact that they have been successfully applied into the modelling of a wide variety of phenomena, ranging from biology, physics to finance. The stochastic process behind fractional operators is linked, in the whole space, to an…

Charis Tsikkou, West Virginia University, Radial solutions to the Cauchy problem for the wave equation and compressible Euler system

SAS 4201

In the first part of this work, we consider the strategy of realizing the solution of the three-dimensional linear wave equation with radial Cauchy data as a limit of radial exterior solutions satisfying vanishing Neumann and Dirichlet conditions, on the exterior of vanishing balls centered at the origin. We insist on robust arguments based on energy methods and strong convergence. Our findings show that while one…

H.T. Banks, North Carolina State University, Population Models-The Prohorov Metric Framework and Aggregate Data Inverse Problems

SAS 4201

We consider nonparametric estimation of probability measures for parameters in problems where only aggregate (population level) data are available. We summarize an existing computational method for the estimation problem which has been developed over the past several decades. Theoretical results are presented which establish the existence and consistency of very general (ordinary, generalized and other)…

Alexander Kiselev, Duke University, Small scale formation in ideal fluids

SAS 4201

The incompressible Euler equation of fluid mechanics describes motion of ideal fluid, and was derived in 1755. In two dimensions, global regularity of solutions is known, and double exponential in time upper bound on growth of the derivatives of solution goes back to 1930s. I will describe a construction of example showing sharpness of this…

Wen Shen, Penn State University, Scalar Conservation Laws with Discontinuous and Regulated Flux

SAS 4201

Conservation laws with discontinuous flux functions arise in various models. In this talk we consider solutions to a class of conservation laws with discontinuous flux, where the flux function is discontinuous in both time and space, but regulated in the two variables. Convergence and the uniqueness of the vanishing viscosity limit for the viscous equation…

Boris Mordukhovich, Wayne State University, Criticality of Lagrange Multipliers in Conic Programming with Applications to Superlinear Convergence of SQP

SAS 4201

His talk concerns the study of criticality of Lagrange multipliers in variational systems that have been recognized in both theoretical and numerical aspects of optimization and variational analysis. In contrast to the previous developments dealing with polyhedral KKT systems and the like, we now focus on general nonpolyhedral systems that are associated, in particular, with…

Oleksandr Misiats, Virginia Commonwealth University, Patterns around us: a calculus of variations prospective

SAS 4201

Crumples in a sheet of paper, wrinkles on curtains, cracks in metallic alloys, and defects in superconductors are examples of patterns in materials. A thorough understanding of the underlying phenomenon behind the pattern formation provides a different prospective on the properties of the existing materials and contributes to the development of new ones. In my talk…

Angot Philippe, Aix-Marseille Université, Mathematical modeling and analysis towards the open problem of flow at a fluid-porous interface

We discuss mathematical modeling and analysis of the incompressible viscous flow at the interface of permeable media. Very recently, a simplified theory with asymptotic modeling and related approximations was extensively developed by to provide physically relevant jump interface conditions for the two- or three-dimensional non-inertial flow at the interface of a permeable medium. The results…

Michele Palladino, GSSI, Italy, Modeling the root growth: an optimal control approach

In this talk we will propose a new framework to model control systems in which a dynamic friction occurs. In particular, such a framework is motivated by the study of the movement of a robotic root tip in the soil. The model consists in a controlled differential inclusion with a dissipative, upper semi-continuous right hand…

Kazufumi Ito, NC State, Optimal control of sate constrained PDEs system with Spars controls

In this talk we discuss a point-wise state constraint problem for a general class of PDEs optimal control problems and sparsity optimization. We use the penalty formulation and derive the necessary optimality condition based on the Lagrange multiplier theory.The existence of Lagrange multiplier associated with  the point-wise state constraint as a measure is established. Also we…

Yulong Lu, Duke University, Understanding and accelerating statistical sampling algorithms: a PDE perspective

A fundamental problem in Bayesian inference and statistical machine learning is to efficiently sample from probability distributions. Standard Markov chain Monte Carlo methods could be prohibitively expensive due to various complexities of the target distribution, such as multimodality, high dimensionality, large datesets, etc. To improve the sampling efficiency, several new interesting ideas/methods have recently been proposed in the community…

Mikhail Klibanov, UNC Charlotte, Carleman Estimates for Globally Convergent Numerical Methods for Coefficient Inverse Problems

The ill-posedness and nonlinearity are two factors causing the phenomenon of multiple local minima and ravines of conventional least squares cost functionals for Coefficient Inverse Problems. Since any minimization method can stop at any point of a local minimum, then the problem of numerical solution of any Coefficient Inverse Problems becomes inherently unstable and so…

Cass Miller, UNC, Toward a New Generation of Models to Simulate Two-Fluid Flow in Porous Media

Two fluid flow in porous medium systems is an important application in many different areas of science and engineering.  Overwhelmingly, it is necessary to mathematically model the behavior of applications of concern at an averaged scale where the juxtaposed position of the phases is not resolved in detail.  This length scale is called the macroscale…

Shan Gao, Beijing Institute of Technology, Discrete Geometrically-Exact Beams

A geometrically-exact beam is a nonlinear field-theoretic model for elongated elastic objects. It utilizes moving frames to reduce the number of system’s independent spatial variables, which is a further development of Euler’s approach to the rotational dynamics of rigid bodies. The talk will discuss the dynamics and geometrically-inspired discretization for structure-preserving numerical simulations of free,…

Rossana Capuani, Metric entropy for functions of bounded total generalized variation

We establish a sharp estimate for a minimal number of binary digits (bits) needed to represent all bounded total generalized variation functions taking values in a general totally bounded metric space (E, ρ) up to an accuracy of  epsilon > 0 with respect to the L^1-distance. Such an estimate is explicitly computed in terms of…

CANCELED: Christopher K Jones, UNC, How far the dynamical systems perspective be pushed for studying nonlinear waves and patterns in multi-dimensions?

Geometric dynamical systems ideas have been very successful in determining traveling and standing waves in one space dimension.  Techniques that have proved important for their existence and stability include geometric singular perturbation theory, Lin’s Method, the Evans Function and the Maslov Index. Spatial Dynamics constitutes an approach to extending these ideas to higher-dimensional domains that…

CANCELED: Hung Tran, University of Wisconsin Madison, Coagulation-Fragmentation equations with multiplicative coagulation kernel and constant fragmentation kernel

We study a critical case of Coagulation-Fragmentation equations with multiplicative coagulation kernel and constant fragmentation kernel. Our method is based on the study of viscosity solutions to a new singular Hamilton-Jacobi equation, which results from applying the Bernstein transform to the original Coagulation-Fragmentation equation. Our results include wellposedness, regularity and long-time behaviors of viscosity solutions…