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We consider the minimization problem for an integral functional $J$, possibly non-convex and non-coercive in $W^{1,1}_0(\Omega)$, where $\Omega\subset\R^n$ is a bounded smooth set. We prove sufficient conditions in order to guarantee that a…

Analysis of PDEs · Mathematics 2019-07-25 G. Crasta , A. Malusa

We study problems with stochastic uncertainty information on intervals for which the precise value can be queried by paying a cost. The goal is to devise an adaptive decision tree to find a correct solution to the problem in consideration…

Data Structures and Algorithms · Computer Science 2021-09-27 Steven Chaplick , Magnús M. Halldórsson , Murilo S. de Lima , Tigran Tonoyan

In this paper, we study an inverse problem for identifying the initial value in a space-time fractional diffusion equation from the final time data. We show the identifiability of this inverse problem by proving the existence of its unique…

Analysis of PDEs · Mathematics 2024-12-10 Mohamed BenSalah , Salih Tatar

Identifying self-similarity is key to understanding and modelling a plethora of phenomena in fluid mechanics. Unfortunately, this is not always possible to perform formally in highly complex flows. We propose a methodology to extract the…

Data Analysis, Statistics and Probability · Physics 2025-10-08 Nikos Bempedelis , Luca Magri , Konstantinos Steiros

Data assimilation involves estimating the state of a system by combining observations from various sources with a background estimate of the state. The weights given to the observations and background state depend on their specified error…

Numerical Analysis · Mathematics 2025-03-13 Olivier Goux , Anthony Weaver , Selime Gürol , Oliver Guillet , Andrea Piacentini

In this paper we study the analytic solutions of Burgers-type nonlinear fractional equations by means of the Invariant Subspace Method. We first study a class of nonlinear equations directly related to the time-fractional Burgers equation.…

Exactly Solvable and Integrable Systems · Physics 2013-06-11 P. Artale Harris , R. Garra

Matrix valued data has become increasingly prevalent in many applications. Most of the existing clustering methods for this type of data are tailored to the mean model and do not account for the dependence structure of the features, which…

Machine Learning · Statistics 2023-12-07 Inbeom Lee , Siyi Deng , Yang Ning

Variational inference methods for latent variable statistical models have gained popularity because they are relatively fast, can handle large data sets, and have deterministic convergence guarantees. However, in practice it is unclear…

Methodology · Statistics 2017-03-22 Hachem Saddiki , Andrew C. Trapp , Patrick Flaherty

We construct a continuous Lagrangian, strictly convex and superlinear in the third variable, such that the associated variational problem has a Lipschitz minimizer which is non-differentiable on a dense set. More precisely, the upper and…

Classical Analysis and ODEs · Mathematics 2015-05-18 Richard Gratwick , David Preiss

This paper considers the problem of determining an optimal control action based on observed data. We formulate the problem assuming that the system can be modelled by a nonlinear state-space model, but where the model parameters, state and…

Optimization and Control · Mathematics 2021-07-02 Johannes N. Hendriks , James R. Z. Holdsworth , Adrian G. Wills , Thomas B. Schon , Brett Ninness

In this article, we develop a fully discrete numerical scheme for the one-dimensional (1D) and two-dimensional (2D) viscous Burgers equations with nonlinear Neumann boundary feedback control. The temporal discretization employs a…

Numerical Analysis · Mathematics 2026-02-03 Shishu Pal Singh , Sudeep Kundu

In this paper, we investigate the stochastic damped Burgers equation with multiplicative noise defined on the entire real line. We demonstrate the existence and uniqueness of a mild solution to the stochastic damped Burgers equation and…

Dynamical Systems · Mathematics 2025-06-10 Zhenxin Liu , Zhiyuan Shi

Data assimilation method consists in combining all available pieces of information about a system to obtain optimal estimates of initial states. The different sources of information are weighted according to their accuracy by the means of…

Data Analysis, Statistics and Probability · Physics 2014-04-30 Angélique Ponçot , Jean-Philippe Argaud , Bertrand Bouriquet , Patrick Erhard , Serge Gratton , Olivier Thual

This paper considers a distributed adaptive optimization problem, where all agents only have access to their local cost functions with a common unknown parameter, whereas they mean to collaboratively estimate the true parameter and find the…

Optimization and Control · Mathematics 2025-09-03 Yaqun Yang , Jinlong Lei , Guanghui Wen , Yiguang Hong

Constraining a numerical weather prediction (NWP) model with observations via 4D variational (4D-Var) data assimilation is often difficult to implement in practice due to the need to develop and maintain a software-based tangent linear…

Machine Learning · Computer Science 2024-08-07 Kylen Solvik , Stephen G. Penny , Stephan Hoyer

We prove existence and uniqueness of minimizers for a family of energy functionals that arises in Elasticity and involves polyconvex integrands over a certain subset of displacement maps. This work extends previous results by Awi and Gangbo…

Analysis of PDEs · Mathematics 2019-06-05 Romeo Awi , Marc Sedjro

We focus on existence and rigidity problems of the vectorial Peierls-Nabarro (PN) model for dislocations. Under the assumption that the misfit potential on the slip plane only depends on the shear displacement along the Burgers vector, a…

Analysis of PDEs · Mathematics 2022-11-08 Yuan Gao , Jian-Guo Liu , Zibu Liu

We consider the problem of minimizing the sum of submodular set functions assuming minimization oracles of each summand function. Most existing approaches reformulate the problem as the convex minimization of the sum of the corresponding…

Machine Learning · Computer Science 2019-05-28 K S Sesh Kumar , Francis Bach , Thomas Pock

We consider the following basic problem: given an $n$-variate degree-$d$ homogeneous polynomial $f$ with real coefficients, compute a unit vector $x \in \mathbb{R}^n$ that maximizes $|f(x)|$. Besides its fundamental nature, this problem…

Data Structures and Algorithms · Computer Science 2017-04-25 Vijay Bhattiprolu , Mrinalkanti Ghosh , Venkatesan Guruswami , Euiwoong Lee , Madhur Tulsiani

Variational data assimilation technique applied to identification of optimal approximations of derivatives near boundary is discussed in frames of one-dimensional wave equation. Simplicity of the equation and of its numerical scheme allows…

Mathematical Physics · Physics 2015-05-13 Eugene Kazantsev