Buscar
Mostrando ítems 1-10 de 560
Lower bounds for the local cyclicity for families of centers
(Elsevier B.V., 2021-02-25)
In this paper, we are interested in how the local cyclicity of a family of centers depends on the parameters. This fact was pointed out in [21], to prove that there exists a family of cubic centers, labeled by C D-31(12) ...
Lower bounds for the local cyclicity of centers using high order developments and parallelization
(Elsevier B.V., 2021-01-15)
We are interested in small-amplitude isolated periodic orbits, so-called limit cycles, surrounding only one equilibrium point, that we locate at the origin. We develop a parallelization technique to study higher order ...
Local cyclicity in low degree planar piecewise polynomial vector fields
(Elsevier B.V., 2021-08-01)
In this work, we are interested in isolated crossing periodic orbits in planar piecewise polynomial vector fields defined in two zones separated by a straight line. In particular, in the number of limit cycles of small ...
Centers and limit cycles of vector fields defined on invariant spheres
(Springer, 2021-09-25)
The aim of this paper is the study of the center-focus and cyclicity problems inside the class X of 3-dimensional vector fields that admit a first integral that leaves invariant any sphere centered at the origin. We classify ...
Centers and Limit Cycles of Vector Fields Defined on Invariant Spheres
(2021-12-01)
The aim of this paper is the study of the center-focus and cyclicity problems inside the class X of 3-dimensional vector fields that admit a first integral that leaves invariant any sphere centered at the origin. We classify ...
Orbitally symmetric systems with applications to planar centers
(2021-10-01)
We present a generalization of the most usual symmetries in differential equations known as the time-reversibility and the equivariance ones. We check that the typical properties are also valid for the new definition that ...
Probing the electronic delocalization in a cyclic pyrazine ruthenium cluster hexamer
(ELSEVIER SCIENCE BV, 2010)
[Ru(3)O(CH(3)COO)(6)(pz)(CO)](6) is a cyclic hexamer species encompassing six triangular ruthenium cluster centers bridged by pyrazine ligands. The electronic communication among the cluster units strongly depends on their ...
BASS CYCLIC UNITS AS FACTORS IN A FREE GROUP IN INTEGRAL GROUP RING UNITS
(WORLD SCIENTIFIC PUBL CO PTE LTD, 2011)
Marciniak and Sehgal showed that if u is a non-trivial bicyclic unit of an integral group ring then there is a bicyclic unit v such that u and v generate a non-abelian free group. A similar result does not hold for Bass ...
Trace form associated to cyclic number fields of ramified odd prime degree
(2019-01-01)
In this work, we computate the trace form Tr k/Q (x2) associated to a cyclic number field of odd prime degree p, where p ramified in and x belongs to the ring of integers of . Furthermore, we use this trace form to calculate ...
Cyclic voltammetric behaviour of the o-2/o-2(center dot-) redox couple at a hmde and its interaction with nisoldipine
(ELSEVIER SCIENCE B.V., 2002)