Results 61 to 70 of about 471,373 (286)

Second-order bifurcation of limit cycles from a quadratic reversible center

Electronic Journal of Differential Equations, 2017
This article concerns the bifurcation of limit cycles from a quadratic integrable and non-Hamiltonian system. By using the averaging theory, we show that under any small quadratic homogeneous perturbation, there is at most one limit cycle for the ...
Linping Peng, Bo Huang
doaj  

The dynamics of the gravitational two-body problem at fourth post-Newtonian order and at quadratic order in the Newton constant

, 2012
We derive the conservative part of the Lagrangian and the energy of a gravitationally bound two-body system at fourth post-Newtonian order, up to terms quadratic in the Newton constant.
J. Winicour, L. Blanchet, L. Blanchet, Riccardo Sturani, Stefano Foffa, T. Damour, T. Futamase, W. D. Goldberger   +7 more
core   +1 more source

Characterization of Defect Distribution in an Additively Manufactured AlSi10Mg as a Function of Processing Parameters and Correlations with Extreme Value Statistics

Advanced Engineering Materials, EarlyView.
Predicting extreme defects in additive manufacturing remains a key challenge limiting its structural reliability. This study proposes a statistical framework that integrates Extreme Value Theory with advanced process indicators to explore defect–process relationships and improve the estimation of critical defect sizes. The approach provides a basis for
Muhammad Muteeb Butt, Varma Kvvssn, Hossein Laieghi, Zia Uddin, Peyman Ansari, E. Kıvanç Sadak, Can Barış Toprak, Hüseyin Kızıl, Enrico Salvati   +8 more
wiley   +1 more source

Centers on center manifolds in a quadratic system obtained froma scalar third-order differential equation

Electronic Journal of Differential Equations, 2011
We give affirmative answers to two questions concerning the existence of centers on local center manifolds at equilibria of a quadratic system in the three dimensional space.
Warley Ferreira da Cunha, Fabio Scalco Dias, Luis Fernando Mello   +2 more
doaj  

RF cavity design exploiting a new derivative-free trust region optimization approach

Journal of Advanced Research, 2015
In this article, a novel derivative-free (DF) surrogate-based trust region optimization approach is proposed. In the proposed approach, quadratic surrogate models are constructed and successively updated.
Abdel-Karim S.O. Hassan, Hany L. Abdel-Malek, Ahmed S.A. Mohamed, Tamer M. Abuelfadl, Ahmed E. Elqenawy   +4 more
doaj   +1 more source

Influence of the trap shape on the superfluid-Mott transition in ultracold atomic gases

, 2008
The coexistence of superfluid and Mott insulator, due to the quadratic confinement potential in current optical lattice experiments, makes the accurate detection of the superfluid-Mott transition difficult.
F. Alet, Fu Chun Zhang, J. V. Porto, Kai Yu Yang, L. Pitaevskii, Lode Pollet, Matthias Troyer, Ping Nang Ma   +7 more
core   +1 more source

The period function of reversible quadratic centers

Journal of Differential Equations, 2006
In this paper we investigate the bifurcation diagram of the period function associated to a family of reversible quadratic centers, namely the dehomogenized Loud's systems. The local bifurcation diagram of the period function at the center is fully understood using the results of Chicone and Jacobs [C. Chicone, M.
Mardešić, P., Marín, D., Villadelprat, J.   +2 more
openaire   +4 more sources

A Thermodynamic 3D Model for the Simulation of Diffusion‐Controlled Alloying Processes in Heterogeneous Material Structures

Advanced Engineering Materials, EarlyView.
A numerical model resulting from irreversible thermodynamics for describing transport processes is introduced, focusing on thermodynamic activity gradients as the actual driving force for diffusion. Implemented in CUDA C++ and using CalPhaD methods for determining the necessary activity data, the model accurately simulates interdiffusion in aluminum ...
Ulrich Holländer, Leonhard Holländer, André Langohr, Hans Jürgen Maier   +3 more
wiley   +1 more source

Complete geometric invariant study of two classes of quadratic systems

Electronic Journal of Differential Equations, 2012
In this article, using affine invariant conditions, we give a complete study for quadratic systems with center and for quadratic Hamiltonian systems.
Joan C. Artes, Jaume Llibre, Nicolae Vulpe   +2 more
doaj  

3D Yang-Mills confining properties from a non-Abelian ensemble perspective

Journal of High Energy Physics, 2020
In this work, we propose a 3D ensemble measure for center-vortex worldlines and chains equipped with non-Abelian degrees of freedom. We derive an effective field description for the center-element average where the vortices get represented by N flavors ...
D. R. Junior, L. E. Oxman, G. M. Simões
doaj   +1 more source