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Linearizable planar differential systems via the inverse integrating factor
Journal of Physics A: Mathematical and Theoretical, 2008Our purpose in this paper is to study when a planar differential system polynomial in one variable linearizes in the sense that it has an inverse integrating factor which can be constructed by means of the solutions of linear differential equations. We give several families of differential systems which illustrate how the integrability of the system ...
Héctor Giacomini +2 more
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Journal of Physics A: Mathematical and General, 2000
The authors show new first integrals to planar Lotka-Volterra systems that have a polynomial inverse integrating factor. These systems may be characterized by equalities among the coefficients of the system. Moreover, all planar Lotka-Volterra systems which have a polynomial first integral are characterized and an explicit expression of these first ...
Cairó, Laurent, Llibre, Jaume
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The authors show new first integrals to planar Lotka-Volterra systems that have a polynomial inverse integrating factor. These systems may be characterized by equalities among the coefficients of the system. Moreover, all planar Lotka-Volterra systems which have a polynomial first integral are characterized and an explicit expression of these first ...
Cairó, Laurent, Llibre, Jaume
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Existence and vanishing set of inverse integrating factors for analytic vector fields
Bulletin of the London Mathematical Society, 2009In this paper we address the problem of existence of inverse integrating factors for an analytic planar vector field in a neighborhood of its nonwandering sets. It is proved that there always exists a smooth inverse integrating factor in a neighborhood of a limit cycle, obtaining a necessary and sufficient condition for the existence of an analytic one.
Alberto Enciso, Daniel Peralta-Salas
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Algebraic Inverse Integrating Factors for a Class of Generalized Nilpotent Systems
2016Usually, the study of differential systems with linear part null is done using quasi-homogeneous expansions of vector fields. Here, we use this technique for analyzing the existence of an inverse integrating factor for generalized nilpotent systems, in general non-integrable, whose lowest-degree quasi-homogeneous term is the Hamiltonian system \(y^{2 ...
Antonio Algaba +3 more
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IEEE Transactions on Geoscience and Remote Sensing, 1984
The development of both direct and inverse wave propagation theories at the level of the reduced scalar Helmholtz equation is addressed. The principal constructive tool is the factorization analysis of the Helmholtz equation which derives from the physically suggestive picture of decoupled forward and backward wave propagation appropriate for ...
Louis Fishman, John J. Mccoy
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The development of both direct and inverse wave propagation theories at the level of the reduced scalar Helmholtz equation is addressed. The principal constructive tool is the factorization analysis of the Helmholtz equation which derives from the physically suggestive picture of decoupled forward and backward wave propagation appropriate for ...
Louis Fishman, John J. Mccoy
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Inverse integrating factor overview
AIP Conference Proceedings, 2023Anmar Hashim Jasim +1 more
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2016 IEEE International Symposium on Antennas and Propagation (APSURSI), 2016
A new HSS (Hierarchically Semiseparable) direct matrix solution algorithm, including both factorization and inversion, is developed for solving the volume integral equation (VIE) for large-scale electrodynamic analysis. This direct solution algorithm is exact in the sense that the matrix factorization, inversion, and solution do not involve any ...
Miaomiao Ma, Dan Jiao
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A new HSS (Hierarchically Semiseparable) direct matrix solution algorithm, including both factorization and inversion, is developed for solving the volume integral equation (VIE) for large-scale electrodynamic analysis. This direct solution algorithm is exact in the sense that the matrix factorization, inversion, and solution do not involve any ...
Miaomiao Ma, Dan Jiao
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A quality factor inversion method of Markov chain Monte Carlo integrating well-log and seismic data
GeophysicsABSTRACT The Q-value quantitatively characterized the extent of seismic wave absorption in rocks, aided in the compensation of seismic data, and supported the detection of oil and gas properties. Conventional Q-value extraction methods are typically suitable for vertical seismic profiling (VSP).
Bo Li +4 more
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1989
The analysis and fast, accurate numerical computation of the wave equations of classical physics are often quite difficult for rapidly changing, multidimensional environments extending over many wavelengths. This is particularly so for environments characterized by a refractive index field with a compact region of arbitrary (n-dimensional) variability ...
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The analysis and fast, accurate numerical computation of the wave equations of classical physics are often quite difficult for rapidly changing, multidimensional environments extending over many wavelengths. This is particularly so for environments characterized by a refractive index field with a compact region of arbitrary (n-dimensional) variability ...
openaire +1 more source