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We study topology optimization governed by the incompressible Navier-Stokes flows using a phase field model. Novel stabilized semi-implicit schemes for the gradient flows of Allen-Cahn and Cahn-Hilliard types are proposed for solving the…

Numerical Analysis · Mathematics 2024-05-09 Jiajie Li , Shengfeng Zhu

Evolutionary PDEs for geometric order parameters that admit propagating singular solutions are introduced and discussed. These singular solutions arise as a result of the competition between nonlinear and nonlocal processes in various…

Adaptation and Self-Organizing Systems · Physics 2009-11-11 Darryl D. Holm , Vakhtang Putkaradze

The latent space of normalizing flows must be of the same dimensionality as their output space. This constraint presents a problem if we want to learn low-dimensional, semantically meaningful representations. Recent work has provided…

Machine Learning · Statistics 2020-06-17 Artur Bekasov , Iain Murray

We focus on a family of nonlinear continuity equations for the evolution of a non-negative density $\rho$ with a continuous and compactly supported nonlinear mobility $\mathrm{m}(\rho)$ not necessarily concave. The velocity field is the…

Analysis of PDEs · Mathematics 2025-11-19 José Antonio Carrillo , Alejandro Fernández-Jiménez , David Gómez-Castro

Optimization under structural constraints is typically analyzed through projection or penalty methods, obscuring the geometric mechanism by which constraints shape admissible dynamics. We propose an operator-theoretic formulation in which…

Optimization and Control · Mathematics 2026-03-10 Changkai Li

A freely falling stream of weakly cohesive granular particles is modeled and analysed with help of event driven simulations and continuum hydrodynamics. The former show a breakup of the stream into droplets, whose size is measured as a…

Soft Condensed Matter · Physics 2015-06-04 Stephan Ulrich , Annette Zippelius

A relaxed notion of displacement convexity is defined and used to establish short time existence and uniqueness of Wasserstein gradient flows for higher order energy functionals. As an application, local and global well-posedness of…

Analysis of PDEs · Mathematics 2012-01-18 Ehsan Kamalinejad

We prove that the standard gradient flow in parameter space that underlies many training algorithms in deep learning can be continuously deformed into an adapted gradient flow which yields (constrained) Euclidean gradient flow in output…

Machine Learning · Computer Science 2026-02-02 Thomas Chen , Patrícia Muñoz Ewald

Despite the widespread use of gradient-based algorithms for optimizing high-dimensional non-convex functions, understanding their ability of finding good minima instead of being trapped in spurious ones remains to a large extent an open…

We study the equation of one-dimensional quasistatic nonlinear viscoelasticity with Dirichlet boundary conditions, in the particular case that the underlying dissipation geometry (provided by the viscosity) is comparable to the Bhattacharya…

Analysis of PDEs · Mathematics 2026-05-12 Alexander Mielke , Billy Sumners

We derive pointwise curvature estimates for graphical mean curvature flows in higher codimensions. To the best of our knowledge, this is the first such estimates without assuming smallness of first derivatives of the defining map. An…

Differential Geometry · Mathematics 2014-12-03 Knut Smoczyk , Mao-Pei Tsui , Mu-Tao Wang

This master thesis looks at the gradient flow of the length functional on embedded loops. The space of embedded loops is endowed with a scale structure so that the length functional becomes scale smooth. For certain underlying manifolds,…

Symplectic Geometry · Mathematics 2021-04-28 Oliver Neumeister

Applications of normalizing flows to the sampling of field configurations in lattice gauge theory have so far been explored almost exclusively in two space-time dimensions. We report new algorithmic developments of gauge-equivariant flow…

In this paper, we consider the following general evolution equation $$ u_t=\Delta_fu+au\log^\alpha u+bu $$ on smooth metric measure spaces $(M^n, g, e^{-f}dv)$. We give a local gradient estimate of Souplet-Zhang type for positive smooth…

Differential Geometry · Mathematics 2016-10-12 Nguyen Thac Dung , Kieu Thi Thuy Linh , Ninh Van Thu

In this article we consider the length functional defined on the space of immersed planar curves. The $L^2(ds)$ Riemannian metric gives rise to the curve shortening flow as the gradient flow of the length functional. Motivated by the…

Differential Geometry · Mathematics 2021-03-04 Philip Schrader , Glen Wheeler , Valentina-Mira Wheeler

We investigate the gradient flow of the $L^2$ norm of the Riemannian curvature on surfaces. We show long time existence with arbitrary initial data, and exponential convergence of the volume normalized flow to a constant scalar curvature…

Differential Geometry · Mathematics 2010-08-26 Jeffrey Streets

This paper exploits the theory of geometric gradient flows to introduce an alternative regularization of the thin-film equation. The solution properties of this regularization are investigated via a sequence of numerical simulations whose…

Fluid Dynamics · Physics 2020-02-20 Darryl D. Holm , Lennon Ó Náraigh , Cesare Tronci

This paper is concerned with the optimal shape design of the newtonian viscous incompressible fluids driven by the stationary nonhomogeneous Navier-Stokes equations. We use three approaches to derive the structures of shape gradients for…

Optimization and Control · Mathematics 2007-05-23 Zhiming Gao , Yichen Ma , Hongwei Zhuang

In this work, we present a new approach to analyze the gradient flow for a positive semi-definite matrix denoising problem in an extensive-rank and high-dimensional regime. We use recent linear pencil techniques of random matrix theory to…

Machine Learning · Statistics 2023-03-17 Antoine Bodin , Nicolas Macris

Accurate polyp segmentation remains challenging due to irregular lesion morphologies, ambiguous boundaries, and heterogeneous imaging conditions. While U-Net variants excel at local feature fusion, they often lack explicit mechanisms to…

Image and Video Processing · Electrical Eng. & Systems 2025-02-27 Pu Wang , Huaizhi Ma , Zhihua Zhang , Zhuoran Zheng