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71.
Nonholonomic systems are described by the Lagrange-D’Alembert’s principle. The presence of symmetry leads, upon the choice
of an arbitrary principal connection, to a reduced D’Alembert’s principle and to the Lagrange-D’Alembert-Poincaré reduced
equations. The case of rolling constraints has a long history and it has been the purpose of many works in recent times. In
this paper we find reduced equations for the case of a thick disk rolling on a rough surface, sometimes called Euler’s disk, using a 3-dimensional abelian group of symmetry. We also show how the reduced system can be transformed into a single second
order equation, which is an hypergeometric equation. 相似文献
72.
It is proved that the nilpotent Lie algebra generated by a family of decomposable operators generates an Engel- Banach algebra.
We also proved that if a Lie algebra of quasinilpotent operators is essentially nilpotent, then the Banach algebra generated
by this Lie algebra consists of quasinilpotent operators. 相似文献
73.
Jurie Conradie 《Positivity》2006,10(3):591-606
The possibility of characterizing the Mackey topology of a dual pair of vector spaces as a generalized inductive limit (or
mixed) topology is investigated. Positive answers are given for a wide range of dual pairs of Riesz spaces (vector lattices)
and non-commutative Banach function spaces (or symmetric operator spaces). 相似文献
74.
We consider the Dirichlet problem for a class of anisotropic degenerate elliptic equations. New a priori estimates for solutions and for the gradient of solutions are established. Based on these estimates sufficient conditions guaranteeing the solvability of the problem are formulated. The results are new even in the semilinear case when the principal part is the Laplace operator. 相似文献
75.
We shall be concerned with the existence of heteroclinic orbits for the second order Hamiltonian system 7000964-si1.gif">, where q∈Rn and V∈C1(R×Rn,R), V?0. We will assume that V and a certain subset M⊂Rn satisfy the following conditions. M is a set of isolated points and #M?2. For every sufficiently small ε>0 there exists δ>0 such that for all (t,z)∈R×Rn, if d(z,M)?ε then −V(t,z)?δ. The integrals 7000964-si13.gif">, z∈M, are equi-bounded and −V(t,z)→∞, as |t|→∞, uniformly on compact subsets of Rn?M. Our result states that each point in M is joined to another point in M by a solution of our system. 相似文献
76.
77.
78.
79.
Werner M. Seiler 《Acta Appl Math》1995,41(1-3):311-322
The computation of a number of arbitrary functions in the general solution is briefly reviewed. The results are used to study normal systems and their symmetry reduction. We discuss the treatment of gauge systems, especially the analysis of gauge fixing conditions. As examples, the Yang-Mills equations with the Lorentz gauge and Einstein's vacuum field equations with harmonic coordinates are considered. 相似文献
80.
A. V. Pazhitnov 《K-Theory》1996,10(4):323-412
Let M be a closed connected smooth manifold with dim M=n6, and :
1(M) Z be an epimorphism. Denote by the group ring of
1(M) and let
–
be its Novikov completion. Let D
* be a free-based finitely generated chain complex over
–
. Assume that D
ii=0 for i1 and in–1 and that D
* has the same simple homotopy type as the Novikov-completed simplicial chain complex of the universal covering M. Let N be an integer. We prove that D
* can be realized, up to the terms of
–
of degree N as the Novikov complex of a Morse map : M S
1, belonging to . Applications to Arnold's conjectures and to the theory of fibering of M over S
1 are given. 相似文献