SEMINAR: Special AMP / MPO / CS Seminar this Wed 3 pm MSC 343 - George Haller, Lagrangian Coherent Structures

[Roland Romeiser <rromeiser@rsmas.miami.edu>]

CSTAMP COLLOQUIUM ON SELECTED TOPICS OF APPLIED MARINE PHYSICS

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SPECIAL JOINT SEMINAR OF RSMAS-AMP, RSMAS-MPO,
AND THE UM DEPARTMENT OF COMPUTER SCIENCE

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SPEAKER
George Haller
Department of Mechanical Engineering and
Department of Mathematics & Statistics
McGill University, Montreal, Canada
 (guest of J. Olascoaga and J. Beron-Vera)

TITLE
Variational Theory of
Lagrangian Coherent Structures

DATE
Wednesday, March 2, 2011

TIME
3:00 pm

VENUE
RSMAS, classroom MSC 343

Abstract - Lagrangian Coherent Structures (LCS) are distinguished invariant manifolds that govern the evolution of complex material patterns in moving fluids and solids. Examples of such patterns include oil spills, plankton populations, schools of fish and moving crowds. Because of their finite lifetime and aperiodic nature, LCS have been challenging to locate, predict or control.
In this talk, I describe a new variational theory that enables a mathematically rigorous extraction of LCS from physical flow data. In this approach, hyperbolic LCS are defined as invariant surfaces that extremize an appropriate finite-time normal repulsion or attraction measure in the governing dynamical system. Solving this variational problem leads to computable sufficient and necessary criteria for LCS. I also discuss constrained LCS problems, as well as the robustness of LCS under perturbations, such as numerical errors or data imperfection. Finally, I show applications to oceanic and atmospheric flow data.

As always, all students are strongly encouraged to come.

List of all CSTAMP presentations in this semester:
http://www.rsmas.miami.edu/personal/rromeiser/cstamp_s11.pdf

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Roland Romeiser
Associate Professor
Division of Applied Marine Physics
Rosenstiel School of Marine and Atmospheric Science
University of Miami
4600 Rickenbacker Causeway
Miami, Florida 33149-1031 USA

Phone:  +1 305 421 4645
Fax:    +1 305 421 4701
E-Mail: rromeiser@rsmas.miami.edu
WWW:    www.rsmas.miami.edu/divs/amp/People/Faculty/Romeiser/

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