Liouvillian and analytic integrability of the quadratic vector fields having an invariant ellipse

Autor: Jaume Llibre, Claudia Valls

Publikováno v: Recercat: Dipósit de la Recerca de Catalunya
Varias* (Consorci de Biblioteques Universitáries de Catalunya, Centre de Serveis Científics i Acadèmics de Catalunya)
Dipòsit Digital de Documents de la UAB
Universitat Autònoma de Barcelona
Recercat. Dipósit de la Recerca de Catalunya
instname

Agraïments: The second author is supported by AGAUR grant PIV-DGR-2010 and by FCT through CAMGDS, Lisbon. We characterize the Liouvillian and analytic integrability of the quadratic polynomial vector fields in R2 having an invariant ellipse. More pr

Externí odkaz: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::49e85ce83a850d3f0c0ae4763e5de395
http://hdl.handle.net/2072/410643

On the class number divisibility of pairs of imaginary quadratic fields

Autor: Yoshichika Iizuka

Publikováno v: Journal of Number Theory. 184:122-127

We construct an infinite family of pairs of imaginary quadratic fields Q ( D ) and Q ( D + 1 ) with D ∈ Z whose class numbers are both divisible by 3.

Externí odkaz: https://explore.openaire.eu/search/publication?articleId=doi_________::b26d88366fe9ad45096a13382c777785
https://doi.org/10.1016/j.jnt.2017.08.013

Generalization of quadratic manifolds for reduced order modeling of nonlinear structural dynamics

Autor: Daniel J. Rixen, Shobhit Jain, Paolo Tiso, Johannes B. Rutzmoser

Publikováno v: Computers & Structures. 192:196-209

In this paper, a generalization of the quadratic manifold approach for the reduction of geometrically nonlinear structural dynamics problems is presented. This generalization is obtained by a linearization of the static force with respect to the gene

Externí odkaz: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::2bd61df5da83cd32928f116ede2b8f4d
https://doi.org/10.1016/j.compstruc.2017.06.003

Extensions on ellipsoid bounds for quadratic integer programming

Autor: Francisco Pinillos Nieto, Marcia Fampa

Publikováno v: Journal of Global Optimization. 71:457-482

Ellipsoid bounds for strictly convex quadratic integer programs have been proposed in the literature. The idea is to underestimate the strictly convex quadratic objective function q of the problem by another convex quadratic function with the same co

Externí odkaz: https://explore.openaire.eu/search/publication?articleId=doi_________::ea470067447bd226f40d980ad8ccd41d
https://doi.org/10.1007/s10898-017-0557-2

On the Geometry of Quadratic Second-Order Abel Ordinary Differential Equations

Autor: P. V. Bibikov

Publikováno v: Journal of Mathematical Sciences. 223:667-674

In this paper, we study the contact geometry of second-order ordinary differential equations that are quadratic in the highest derivative (the so-called quadratic Abel equations). Namely, we realize each quadratic Abel equation as the kernel of some

Externí odkaz: https://explore.openaire.eu/search/publication?articleId=doi_________::819dc63ee2068ad60460b61d97b302fa
https://doi.org/10.1007/s10958-017-3376-6