This paper presents the effect of preload on nonlinear dynamic behavior of a rigid rotor supported by two-lobe aerodynamic noncircular journal bearing. A finite element method is employed to solve the Reynolds equation in static and dynamical states and the dynamical equations are solved using Runge-Kutta method. To analyze the behavior of the rotor center in the horizontal and vertical directi...

Poincar6 often insisted existence in mathematics means logical con-sistency, and formal logic ia the sole guarantor of rigor. The paper joins thisto his view of intuition and his own mathematics. It looks at predicativity andthe infinity Poincar^'s early endorsement of the axiom of choice, and Cantor'sset theory versus Zermelo's axioms. PoincarS discussed constructivism sympa-<l...

Mapping degree, intersection number, and the index of a zero of a vector field are defined. The Poincare-Hopf theorem, which states that under reasonable conditions the sum of the indices of a vector field equals the Euler characteristic of the manifold, is proven. Some consequences are discussed.

The KAM theorem for analytic quasi-integrable anisochronous Hamiltonian systems yields that the perturbation expansion (Lindstedt series) for any quasi-periodic solution with Diophantine frequency vector converges. If one studies the Lindstedt series by following a perturbation theory approach, one finds that convergence is ultimately related to the presence of cancellations between contributio...

6 H. Poincare, Meth. Nouv., 1 (1892), chap. III; G. D. Birkhoff, loc. cit.' 6 H. Poincar6, op. cit., 2 (1893), chap. XVII. The figure given by Poincar6 assumes that p is positive. However, the case of a negative p may be reduced to the case of a positive p, as seen from (6) by writing v + 1/27 for v. M. J. 0. Strutt, Math. Ann., 99, 625-628 (1928). 8 Cf. A. Wintner, Bull. Astr., 9, 251-253 (193...

The theory of classical electromagnetism is constructed in terms of two exterior differential systems, F − dA = 0, and J − dG = 0, which act as topological constraints on the variety of independent variables {x, y, z, t}. These two fundamental constraints lead to two other independent concepts of topological torsion, A^F, and topological spin, A^G, which are explicitly dependent upon the potent...

Perturbation techniques are frequently used in the study of nonlinear dynamical systems, in particular, for bifurcation and stability analyses. In this paper, four most popular perturbation methods – Lindstedt-Poincaré (LP) approach, timeaveraging (TA), multiple time scales (MTS) and the intrinsic harmonic balancing (IHB) – are particularly considered to compare their accuracy of the bifurcatio...

We consider a fermionic many body system in Zd with short range interaction and quasi-periodic disorder. In the strong disorder regime assuming Diophantine condition on frequencies chemical potential, we prove at $T=0$ exponential decay of correlations vanishing Drude weight, signaling Anderson localization ground state. The proof combines Ward Identities, Renormalization Group KAM Lindstedt se...

We study several properties of a homotopy solution path associated with continuous nonlinear quasi-monotone complementarity problems. We use Poincare-Bohn’s homotopy invariance theorem of degree to derive an alternative theorem. Based on this result, a sufficient condition is established to assure the existence and boundedness of this homotopy solution path. Our results provide a theoretical ba...

We have investigated the appearance of chaos in the one-dimensional Newtonian gravitational three-body system (three masses on a line with -1/r pairwise potential). In the center of mass coordinates this system has two degrees of freedom and can be conveniently studied using Poincare sections. We have concentrated in particular on how the behavior changes when the relative masses of the three b...