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Related papers: Geometric Firefighting in the Half-plane

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This work presents a numerical study of a diffusion flame in a reacting, two-dimensional, turbulent, viscous, multi-component, compressible mixing layer subject to a large favorable streamwise pressure gradient. The boundary-layer equations…

Fluid Dynamics · Physics 2026-04-01 Sylvain L. Walsh , Lei Zhan , Carsten Mehring , Feng Liu , William A. Sirignano

Level set methods are versatile and extensible techniques for general front tracking problems, including the practically important problem of predicting the advance of a firefront across expanses of surface vegetation. Given a rule,…

Numerical Analysis · Mathematics 2007-10-16 V. Mallet , D. E. Keyes , F. E. Fendell

The fractional reaction diffusion equation u_t + Au = g(u) is discussed, where A is a fractional differential operator on the real line with order \alpha between 0 and 2, the C^1 function g vanishes at 0 and 1, and either g is non-negative…

Analysis of PDEs · Mathematics 2009-08-04 Hans Engler

It is well known that fighting a fire is a hard task. The Firefighter problem asks how to optimally deploy firefighters to defend the vertices of a graph from a fire. This problem is NP-Complete on all but a few classes of graphs.…

Data Structures and Algorithms · Computer Science 2022-04-07 Samuel Hand , Jessica Enright , Kitty Meeks

The concept of graph burning and burning number ($bn(G)$) of a graph G was introduced recently [1]. Graph burning models the spread of contagion (fire) in a graph in discrete time steps. $bn(G)$ is the minimum time needed to burn a graph…

Discrete Mathematics · Computer Science 2020-03-23 Zahra Rezai Farokh , Maryam Tahmasbi , Zahra Haj Rajab Ali Tehrani , Yousof Buali

We establish rigorous lower bounds on the speed of traveling fronts and on the bulk burning rate in reaction-diffusion equation with passive advection. The non-linearity is assumed to be of either KPP or ignition type. We consider two main…

Analysis of PDEs · Mathematics 2015-06-26 Alexander Kiselev , Leonid Ryzhik

The burning process on a graph $G$ starts with a single burnt vertex, and at each subsequent step, burns the neighbors of the currently burnt vertices, as well as one other unburnt vertex. The burning number of $G$ is the smallest number of…

Computational Geometry · Computer Science 2022-09-28 J. Mark Keil , Debajyoti Mondal , Ehsan Moradi

We consider random dynamics on the edges of a uniform Cayley tree with $n$ vertices, in which edges are either inflammable, fireproof, or burt. Every inflammable edge is replaced by a fireproof edge at unit rate, while fires start at…

Probability · Mathematics 2010-12-01 Jean Bertoin

We obtain a criterion for pulsating front speed-up by general periodic incompressible flows in two dimensions and in the presence of KPP nonlinearities. We achieve this by showing that the ratio of the minimal front speed and the effective…

Analysis of PDEs · Mathematics 2007-05-23 Lenya Ryzhik , Andrej Zlatos

The severity of wildfires can be mitigated adopting preventive measures like the construction of firebreaks that are strips of land from which the vegetation is completely removed. In this paper, we model the problem of wildfire containment…

Discrete Mathematics · Computer Science 2022-04-13 Marc Demange , Alessia Di Fonso , Gabriele Di Stefano , Pierpaolo Vittorini

The detour between two points u and v (on edges or vertices) of an embedded planar graph whose edges are curves is the ratio between the shortest path in in the graph between u and v and their Euclidean distance. The maximum detour over all…

Metric Geometry · Mathematics 2008-01-08 Adrian Dumitrescu , Annette Ebbers-Baumann , Ansgar Grüne , Rolf Klein , Günter Rote

We study a model for combustion on a boundary. Specifically, we study certain generalized solutions of the equation \[ (-\Delta)^s u = \chi_{\{u>c\}} \] for $0<s<1$ and an arbitrary constant $c$. Our main object of study is the free…

Analysis of PDEs · Mathematics 2018-12-03 Mark Allen , Mariana Smit Vega Garcia

It is well known in the combustion community that curvature effect in general slows down flame propagation speeds because it smooths out wrinkled flames. However, such a folklore has never been justified rigorously. In this paper, as the…

Analysis of PDEs · Mathematics 2018-01-17 Jiancheng Lyu , Jack Xin , Yifeng Yu

A kinetic flux-splitting procedure used in conjunction with local thermodynamic equilibrium in a finite volume allows us to investigate numerically discrete-velocity gas flows. The procedure, outlined for a general discrete-velocity gas, is…

comp-gas · Physics 2008-02-03 Balu Nadiga Galcit

Premixed flames propagating within small channels show complex combustion phenomena that differ from flame propagation at conventional scales. Available experimental and numerical studies have documented stationary/non-stationary and/or…

Fluid Dynamics · Physics 2016-08-02 Mohsen Ayoobi , Ingmar Schoegl

We propose a quantum state distance and develop a family of geometrical quantum speed limits (QSLs) for open and closed systems. The QSL time includes an alternative function by which we derive three QSL times with particularly chosen…

Quantum Physics · Physics 2025-06-18 Zi-yi Mai , Zheng Liu , Chang-shui Yu

From the finite difference method for wave equation on p.c.f. fractals, we would expect that infinite prorogation speed property for wave solutions on a large class of p.c.f. fractals. We prove that is true if the heat kernel satisfies the…

Analysis of PDEs · Mathematics 2012-10-02 Yin-Tat Lee

We study a Caputo time fractional degenerate diffusion equation which we prove to be equivalent to the fractional parabolic obstacle problem, showing that its solution evolves for any $\alpha\in(0,1)$ to the same stationary state, the…

Analysis of PDEs · Mathematics 2020-12-23 Carlo Alberini , Raffaela Capitanelli , Mirko D'Ovidio , Stefano Finzi Vita

The Firefighter problem is to place firefighters on the vertices of a graph to prevent a fire with known starting point from lighting up the entire graph. In each time step, a firefighter may be permanently placed on an unburned vertex and…

Discrete Mathematics · Computer Science 2011-09-23 Marek Cygan , Fedor V. Fomin , Erik Jan van Leeuwen

Recent huge technological development of Unmanned Aerial Vehicles (UAVs) can provide breakthrough means of fighting wildland fires. We propose an innovative forest firefighting system based on the use of a swarm of hundreds of UAVs able to…

Robotics · Computer Science 2020-12-21 Elena Ausonio , Patrizia Bagnerini , Marco Ghio