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Related papers: Optical Flow on Evolving Sphere-Like Surfaces

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Recently, variational methods were successfully applied for computing the optical flow in gray and RGB-valued image sequences. A crucial assumption in these models is that pixel-values do not change under transformations. Nowadays, modern…

Optimization and Control · Mathematics 2021-09-06 Manuel Gräf , Sebastian Neumayer , Ralf Hielscher , Gabriele Steidl , Moritz Liesegang , Tilman Beck

Using complementary numerical approaches at high resolution, we study the late-time behaviour of an inviscid, incompressible two-dimensional flow on the surface of a sphere. Starting from a random initial vorticity field comprised of a…

Fluid Dynamics · Physics 2015-12-08 David G. Dritschel , Wanming Qi , J. B. Marston

We study the evolution of spherically symmetric radiating fluid distributions using the effective variables method, implemented {\it ab initio} in Schwarzschild coordinates. To illustrate the procedure and to establish some comparison with…

General Relativity and Quantum Cosmology · Physics 2009-11-07 W. Barreto , B. Rodríguez , H. Martínez

We study the evolution of the flows and horizontal proper motions in and around a decaying follower sunspot based on time sequences of two-dimensional spectroscopic observations in the visible and white light imaging data obtained over six…

The development of microfluidic devices is still hindered by the lack of robust fundamental building blocks that constitute any fluidic system. An attractive approach is optical actuation because light field interaction is contactless and…

Photospheric vortex flows are thought to play a key role in the evolution of magnetic fields. Recent studies show that these swirling motions are ubiquitous in the solar surface convection and occur in a wide range of temporal and spatial…

Solar and Stellar Astrophysics · Physics 2018-03-07 Iker S. Requerey , Basilio Ruiz Cobo , Milan Gošić , Luis R. Bellot Rubio

Recent research has shown that motile cells can adapt their mode of propulsion depending on the environment in which they find themselves. One mode is swimming by blebbing or other shape changes, and in this paper we analyze a class of…

Fluid Dynamics · Physics 2016-10-10 Qixuan Wang , Hans G. Othmer

The problem of two-phase flow in straight capillaries of polygonal cross section displays many of the dynamic characteristics of rapid interfacial motions associated with pore-scale displacements in porous media. Fluid inertia is known to…

Fluid Dynamics · Physics 2018-07-03 Alexander Yelkhovsky , W. Val Pinczewski

Equilibrium statistical mechanics predicts that inviscid, two-dimensional, incompressible flow on the sphere eventually reaches a state in which spherical harmonic modes of degrees $n=1$ and $n=2$ hold all the energy. By a separate theory,…

Fluid Dynamics · Physics 2023-03-22 Rick Salmon , Nick Pizzo

The dynamics of a single fluid bilayer membrane in an external hydrodynamic flow field is considered. The deterministic equation of motion for the configuration is derived taking into account both viscous dissipation in the surrounding…

Soft Condensed Matter · Physics 2009-10-31 Udo Seifert

We present two accurate and efficient algorithms for solving the incompressible, irrotational Euler equations with a free surface in two dimensions with background flow over a periodic, multiply-connected fluid domain that includes…

We demonstrate the generation of diverse material flow regimes in nematic liquid cells as driven by time-variable active surface anchoring, including no-net flow, oscillatory flow, steady flow, and pulsating flow. Specifically, we…

Soft Condensed Matter · Physics 2025-01-07 Seyed Reza Seyednejad , Miha Ravnik

A Markovian lattice model for photoreceptor cells is introduced to describe the growth of mosaic patterns on fish retina. The radial stripe pattern observed in wild-type zebrafish is shown to be selected naturally during the retina growth,…

Cell Behavior · Quantitative Biology 2017-10-13 Noriaki Ogawa , Tetsuo Hatsuda , Atsushi Mochizuki , Masashi Tachikawa

In this paper we propose a "discrete in continuous" mathematical model for the morphogenesis of the posterior lateral line system in zebrafishes. Our model follows closely the results obtained in recent biological experiments. We rely on a…

Cell Behavior · Quantitative Biology 2017-05-29 Ezio Di Costanzo , Roberto Natalini , Luigi Preziosi

The results of an experimental investigation of a sphere performing torsional oscillations in a Stokes flow are presented. A novel experimental set up was developed which enabled the motion of the sphere to be remotely controlled through…

Fluid Dynamics · Physics 2016-01-20 F. Box , A. B. Thompson , T. Mullin

Event cameras capture changes of illumination in the observed scene rather than accumulating light to create images. Thus, they allow for applications under high-speed motion and complex lighting conditions, where traditional framebased…

Computer Vision and Pattern Recognition · Computer Science 2021-12-21 Vincent Brebion , Julien Moreau , Franck Davoine

The paper addresses the numerical approximation of two variants of hyperbolic mean curvature flow of surfaces in $\mathbb R^3$. For each evolution law we propose both a finite element method, as well as a finite difference scheme in the…

Numerical Analysis · Mathematics 2025-02-11 Klaus Deckelnick , Robert Nürnberg

We analytically derive an equation describing vesicle evolution in a fluid where some stationary flow is excited regarding that the vesicle shape is close to a sphere. A character of the evolution is governed by two dimensionless…

Soft Condensed Matter · Physics 2009-11-13 V. V. Lebedev , K. S. Turitsyn , S. S. Vergeles

We report an extensive numerical study and supporting experimental results on the spectral characterization of optical aberrations in macroscopic fluidic lenses with tunable focal distance and aperture shape. Using a Shack-Hartmann…

Optics · Physics 2023-12-19 Graciana Puentes , Fernando Minotti

We develop and implement a novel lattice Boltzmann scheme to study multicomponent flows on curved surfaces, coupling the continuity and Navier-Stokes equations with the Cahn-Hilliard equation to track the evolution of the binary fluid…

Computational Physics · Physics 2019-12-25 Victor E. Ambruş , Sergiu Busuioc , Alexander J. Wagner , Fabien Paillusson , Halim Kusumaatmaja