Buscar
Mostrando ítems 1-10 de 163
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 ...
New p-dimensional lattices from cyclic extensions
(World Scientific Publ Co Pte Ltd, 2017-10-01)
In this work, p-dimensional point-lattices are constructed from a number field L, where L/Q is a cyclic extension of degree p, an odd unramified prime in L/Q. Families of lattices whose packing densities asymptotically ...
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 ...
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 ...
Limit cycles of discontinuous piecewise polynomial vector fields
(2017-05-01)
When the first average function is non-zero we provide an upper bound for the maximum number of limit cycles bifurcating from the periodic solutions of the center x˙=−y((x2+y2)/2)m and y˙=x((x2+y2)/2)m with m≥1, when we ...
Redei Actions On Finite Fields And Multiplication Map In Cyclic Group
(SIAM PUBLICATIONSPHILADELPHIA, 2015)
Behaviour of displacement piles in sand under cyclic axial loading
(JAPANESE GEOTECHNICAL SOCTOKYO, 2012)
Field experiments have demonstrated that piles driven into sand can respond to axial cyclic loading in Stable, Unstable or Meta-Stable ways, depending on the combinations of mean and cyclic loads and the number of cycles. ...
Construction of perfect space-time codes
(2013-04-29)
In this work, we propose an innovative methodology to extend the construction of minimum and non-minimum delay perfect codes as a subset of cyclic division algebras over ℚ(ζ3), where the signal constellations are isomorphic ...