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121.
Nicholas J. Daras 《Numerical Algorithms》1999,20(4):285-301
Padé-type approximation is the rational function analogue of Taylor’s polynomial approximation to a power series. A general
method for obtaining Padé-type approximants to Fourier series expansions of harmonic functions is defined. This method is
based on the Newton-Cotes and Gauss quadrature formulas. Several concrete examples are given and the convergence behavior
of a sequence of such approximants is studied.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
122.
B. Dacorogna I. Fonseca J. Malý K. Trivisa 《Calculus of Variations and Partial Differential Equations》1999,9(3):185-206
The integral representation for the relaxation of a class of energy functionals where the admissible fields are constrained
to remain on a
-dimensional manifold is obtained. If is a continuous function satisfying for and for all then where is open, bounded, and is the tangential quasiconvexification of f at
belong to the tangent space to at
Received October 10, 1998 / Accepted December 1, 1998 相似文献
123.
We define a 1-parameter family ofr-matrices on the loop algebra of sl2, defining compatible Poisson structures on the associated loop group, which degenerate into the rational and trigonometric structures, and study the Manin triples associated with them.To our friend Dimitri Gurevich, on his 50th birthday 相似文献
124.
Gabriel P. Paternain 《Bulletin of the Brazilian Mathematical Society》1994,25(2):207-211
LetT
* M denote the cotangent bundle of a manifoldM endowed with a twisted symplectic structure [1]. We consider the Hamiltonian flow generated (with respect to that symplectic structure) by a convex HamiltonianH: T
* M, and we consider a compact regular energy level ofH, on which this flow admits a continuous invariant Lagrangian subbundleE. When dimM3, it is known [9] that such energy level projects onto the whole manifoldM, and thatE is transversal to the vertical subbundle. Here we study the case dimM=2, proving that the projection property still holds, while the transversality property may fail. However, we prove that in the case whenE is the stable or unstable subbundle of an Anosov flow, both properties hold. 相似文献
125.
David G. Wagner 《Order》1993,10(2):161-181
Order series of labelled posets are multi-analogues of the more familiar order polynomials; the corresponding multi-analogues of the related representation polynomials are calledE-series. These series can be used to describe the effect of composition of labelled posets on their order polynomials, whence their interest for us. We give a reciprocity theorem forE-series, and show that for an unlabelled poset the form of theE-series depends only upon the comparability graph of the poset. We also prove that theE-series of any labelled poset is a rational power series (in many indeterminates) and give an algorithm for computing it which runs in polynomial time when the poset is strictly labelled and of bounded width. Finally, we give an explicit product formula for theE-series of strictly labelled interval posets.This research was supported by the Natural Sciences and Engineering Research Council of Canada under operating grant #0105392. 相似文献
126.
In this paper, a pendant to a recent survey paper, the authors discuss several open problems in categorical topology. The emphasis is on topology-oriented problems rather than on more general category-oriented ones. In fact, most problems deal with full subconstructs or superconstructs of the constructTop of topological spaces and continuous maps. 相似文献
127.
Igor Kříž 《Combinatorica》1984,4(4):317-319
Forn≧6 there exists a graphG with dimG=n, dimG*≧n+2, whereG* isG with a certain edge added. 相似文献
128.
In this paper we shall first introduce the Pascal k-eliminated functional matrices Pn,k[xyz] and CPn,k[xyz]. Then, using these matrices we obtain several important combinatorial identities. Finally, using the matrix inversion of Pn,k[xyz] and CPn,k[xyz], we derive an interesting formula for Eulerian numbers [7] 相似文献
129.
Florian A. Potra 《Mathematical Programming》2001,91(1):99-115
Sufficient conditions are given for the Q-superlinear convergence of the iterates produced by primal-dual interior-point methods
for linear complementarity problems. It is shown that those conditions are satisfied by several well known interior-point
methods. In particular it is shown that the iteration sequences produced by the simplified predictor–corrector method of Gonzaga
and Tapia, the simplified largest step method of Gonzaga and Bonnans, the LPF+ algorithm of Wright, the higher order methods
of Wright and Zhang, Potra and Sheng, and Stoer, Wechs and Mizuno are Q-superlinearly convergent.
Received: February 9, 2000 / Accepted: February 20, 2001?Published online May 3, 2001 相似文献
130.
In this paper we generalize the construction - introduced by Gagliardi and Grasselli in the closed case - of a coloured-graph
representing the product of two manifolds, starting by two coloured graphs representing the manifolds themselves, to the boundary
case. In particular we study the genus of the graph product of low dimensional manifold ( resp. n-spheres ) with m-disks.
Received September 28, 1998; in final form January 5, 2000 / Published online October 11, 2000 相似文献