منابع مشابه
Lagrangian Coherent Structures
Mounting evidence suggests that fluid advection can effectively be studied by considering special material surfaces, which are referred to here as Lagrangian coherent structures (LCSs). What makes these material surfaces special is their distinguished attracting or repelling nature. Notably, LCS are often locally the most strongly attracting or repellingmaterial surfaces in theflow, and as such...
متن کاملDynamically Consistent Lagrangian Coherent Structures
In this paper, we compute coherent structures based on radar data collected in Monterey Bay during August 2001 and August 2003. The Lagrangian structures are extracted from a finitetime Lyapunov exponent field. In contrast with earlier approaches, the integration time used in computing the Lyapunov exponents is not constant but adapts to the timescales of the different flow regimes present in t...
متن کاملDirac Structures in Lagrangian Mechanics Part I: Implicit Lagrangian Systems
This paper develops the notion of implicit Lagrangian systems and presents some of their basic properties in the context of Dirac structures. This setting includes degenerate Lagrangian systems and systems with both holonomic and nonholonomic constraints, as well as networks of Lagrangian mechanical systems. The definition of implicit Lagrangian systems with a configuration space Q makes use of...
متن کاملDirac Structures in Lagrangian Mechanics Part II: Variational Structures
Part I of this paper introduced the notion of implicit Lagrangian systems and their geometric structure was explored in the context of Dirac structures. In this part, we develop the variational structure of implicit Lagrangian systems. Specifically, we show that the implicit Euler-Lagrange equations can be formulated using an extended variational principle of Hamilton called the Hamilton-Pontry...
متن کاملNon–Lagrangian Construction of Hamiltonian Structures
A method to construct Hamiltonian theories for systems of both ordinary and partial differential equations is presented. The knowledge of a Lagrangian is not at all necessary to achieve the result. The only ingredients required for the construction are one solution of the symmetry (perturbation) equation and one constant of the motion of the original system. It turns out that the Poisson bracke...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Physics Letters B
سال: 2019
ISSN: 0370-2693
DOI: 10.1016/j.physletb.2019.134948