共查询到20条相似文献,搜索用时 906 毫秒
1.
I. Albarreal M.C. Calzada J.L. Cruz E. Fernández-Cara J. Galo M. Marín 《Numerische Mathematik》2002,93(2):201-221
Summary. This paper is concerned with the analysis of the convergence and the derivation of error estimates for a parallel algorithm
which is used to solve the incompressible Navier-Stokes equations. As usual, the main idea is to split the main differential
operator; this allows to consider independently the two main difficulties, namely nonlinearity and incompressibility. The
results justify the observed accuracy of related numerical results.
Received April 20, 2001 / Revised version received May 21, 2001 / Published online March 8, 2002
RID="*"
ID="*" Partially supported by D.G.E.S. (Spain), Proyecto PB98–1134
RID="**"
ID="**" Partially supported by D.G.E.S. (Spain), Proyecto PB96–0986
RID="**"
ID="**" Partially supported by D.G.E.S. (Spain), Proyecto PB96–0986
RID="*"
ID="*" Partially supported by D.G.E.S. (Spain), Proyecto PB98–1134
RID="**"
ID="**" Partially supported by D.G.E.S. (Spain), Proyecto PB96–0986
RID="**"
ID="**" Partially supported by D.G.E.S. (Spain) Proyecto PB96–0986 相似文献
2.
In this work we analyze the paper “Brimberg, J. (1995): The Fermat-Weber location problem revisited. Mathematical Programming 71, 71–76” which claims to close the question on the conjecture posed by Chandrasekaran and Tamir in 1989 on the convergence
of the Weiszfeld algorithm. Some counterexamples are shown to the proofs showed in Brimberg’s paper.
Received: January 1999 / Accepted: December 2001?Published online April 12, 2002
RID="*"
ID="*"Partially supported by PB/11/FS/97 of Fundación Séneca of the Comunidad Autónoma de la Región de Murcia
RID="**"
ID="**"Plan Nacional de Investigación Científica, Desarrollo e Innovación Tecnológica (I+I+D), project TIC2000-1750-C06-06
RID="*"
RID="**" 相似文献
3.
In the assignment game framework, we try to identify those assignment matrices in which no entry can be increased without
changing the core of the game. These games will be called buyer-seller exact games and satisfy the condition that each mixed-pair
coalition attains the corresponding matrix entry in the core of the game. For a given assignment game, a unique buyer-seller
exact assignment game with the same core is proved to exist. In order to identify this matrix and to provide a characterization
of those assignment games which are buyer-seller exact in terms of the assignment matrix, attainable upper and lower core
bounds for the mixed-pair coalitions are found. As a consequence, an open question posed in Quint (1991) regarding a canonical
representation of a “45o-lattice” by means of the core of an assignment game can now be answered.
Received: March 2002/Revised version: January 2003
RID="*"
ID="*" Institutional support from research grants BEC 2002-00642 and SGR2001-0029 is gratefully acknowledged
RID="**"
ID="**" The authors thank the referees for their comments 相似文献
4.
Summary. We derive error bounds for bivariate spline interpolants which are calculated by minimizing certain natural energy norms.
Received March 28, 2000 / Revised version received June 23, 2000 / Published online March 8, 2002
RID="*"
ID="*" Supported by the National Science Foundation under grant DMS-9870187
RID="**"
ID="**" Supported by the National Science Foundation under grant DMS-9803340 and by the Army Research Office under grant DAAD-19-99-1-0160 相似文献
5.
6.
Effects of uncertainties in the domain on the solution of Dirichlet boundary value problems 总被引:1,自引:0,他引:1
Summary. A domain with possibly non-Lipschitz boundary is defined as a limit of monotonically expanding or shrinking domains with
Lipschitz boundary. A uniquely solvable Dirichlet boundary value problem (DBVP) is defined on each of the Lipschitz domains
and the limit of these solutions is investigated. The limit function also solves a DBVP on the limit domain but the problem
can depend on the sequences of domains if the limit domain is unstable with respect to the DBVP. The core of the paper consists
in estimates of the difference between the respective solutions of the DBVP on two close domains, one of which is Lipschitz
and the other can be unstable. Estimates for starshaped as well as rather general domains are derived. Their numerical evaluation
is possible and can be done in different ways.
Received October 16, 2001 / Revised version received January 16, 2002 / Published online: April 17, 2002
RID="*"
ID="*" The research was funded partially by the National Science Foundation under the grants NSF–Czech Rep. INT-9724783 and
NSF DMS-9802367
RID="**"
ID="**" Support for Jan Chleboun coming from the Grant Agency of the Czech Republic through grant 201/98/0528 is appreciated 相似文献
7.
8.
9.
Dedicated to the memory of Paul Erdős
A graph is called -free if it contains no cycle of length four as an induced subgraph. We prove that if a -free graph has n vertices and at least edges then it has a complete subgraph of vertices, where depends only on . We also give estimates on and show that a similar result does not hold for H-free graphs––unless H is an induced subgraph of . The best value of is determined for chordal graphs.
Received October 25, 1999
RID="*"
ID="*" Supported by OTKA grant T029074.
RID="**"
ID="**" Supported by TKI grant stochastics@TUB and by OTKA grant T026203. 相似文献
10.
Let V be a simple vertex operator algebra and G a finite automorphism group. Then there is a natural right G-action on the set of all inequivalent irreducible V-modules. Let be a finite set of inequivalent irreducible V-modules which is closed under the action of G. There is a finite dimensional semisimple associative algebra for a suitable 2-cocycle naturally determined by the G-action on such that and the vertex operator algebra form a dual pair on the sum of V-modules in in the sense of Howe. In particular, every irreducible V-module is completely reducible -module.
Received: 10 September, 2001 / Published online: 29 April 2002
RID="*"
ID="*" Supported by NSF grants and a research grant from the Committee on Research, UC Santa Cruz.
RID="**"
ID="**" Supported by DPST grant from government of Thailand. 相似文献
11.
We prove versions of the Dual Ramsey Theorem and the Dual Ellentuck Theorem for families of partitions which are defined
in terms of games.
Received: 8 July 1999 Published online: 19 December 2002
RID="*"
ID="*" The author wishes to thank the Swiss National Science Foundation for supporting him.
The authors thank the referee for helpful comments.
Mathematics Subject Classification (2000): 03E02, 05D10, 03E35
Key words or phrases: Dual Ramsey Theorem – Dual Ellentuck Theorem – Partitions – Games 相似文献
12.
13.
Summary. In this paper, we consider some nonlinear inexact Uzawa methods for iteratively solving linear saddle-point problems. By
means of a new technique, we first give an essential improvement on the convergence results of Bramble-Paschiak-Vassilev for
a known nonlinear inexact Uzawa algorithm. Then we propose two new algorithms, which can be viewed as a combination of the
known nonlinear inexact Uzawa method with the classical steepest descent method and conjugate gradient method respectively.
The two new algorithms converge under very practical conditions and do not require any apriori estimates on the minimal and
maximal eigenvalues of the preconditioned systems involved, including the preconditioned Schur complement. Numerical results
of the algorithms applied for the Stokes problem and a purely linear system of algebraic equations are presented to show the
efficiency of the algorithms.
Received December 8, 1999 / Revised version received September 8, 2001 / Published online March 8, 2002
RID="*"
ID="*" The work of this author was partially supported by a grant from The Institute of Mathematical Sciences, CUHK
RID="**"
ID="**" The work of this author was partially supported by Hong Kong RGC Grants CUHK 4292/00P and CUHK 4244/01P 相似文献
14.
In this article we present characterizations of locally well-dominated graphs and locally independent well-dominated graphs,
and a sufficient condition for a graph to be k-locally independent well-dominated. Using these results we show that the irredundance number, the domination number and the
independent domination number can be computed in polynomial time within several classes of graphs, e.g., the class of locally
well-dominated graphs.
Received: September 13, 2001 Final version received: May 17, 2002
RID="*"
ID="*" Supported by the INTAS and the Belarus Government (Project INTAS-BELARUS 97-0093)
RID="†"
ID="†" Supported by RUTCOR
RID="*"
ID="*" Supported by the INTAS and the Belarus Government (Project INTAS-BELARUS 97-0093)
05C75, 05C69
Acknowledgments. The authors thank the referees for valuable suggestions. 相似文献
15.
It is proved that, for any ɛ>0 and n>n
0(ɛ), every set of n points in the plane has at most triples that induce isosceles triangles. (Here e denotes the base of the natural logarithm, so the exponent is roughly 2.136.) This easily implies the best currently known
lower bound, , for the smallest number of distinct distances determined by n points in the plane, due to Solymosi–Cs. Tóth and Tardos.
Received: February, 2002 Final version received: September 15, 2002
RID="*"
ID="*" Supported by NSF grant CCR-00-86013, PSC-CUNY Research Award 63382-00-32, and OTKA-T-032452
RID="†"
ID="†" Supported by OTKA-T-030059 and AKP 2000-78-21 相似文献
16.
17.
18.
Sándor Jenei 《Archive for Mathematical Logic》2003,42(5):489-514
We generalize the notions of Girard algebras and MV-algebras by introducing rotation-invariant semigroups. Based on a geometrical
characterization, we present five construction methods which result in rotation-invariant semigroups and in particular, Girard
algebras and MV-algebras. We characterize divisibility of MV-algebras, and point out that integrality of Girard algebras follows
from their other axioms.
Received: 7 January 2002 / Revised version: 4 April 2002 /
Published online: 19 December 2002
RID="*"
ID="*" Supported by the National Scientific Research Fund Hungary (OTKA F/032782).
Mathematics Subject Classification (2000): 20M14, 06F05
Key words or phrases: Residuated lattice – Conjunction for non-classical logics 相似文献
19.
Dedicated to the memory of Paul Erdős
We provide an elementary proof of the fact that the ramsey number of every bipartite graph H with maximum degree at most is less than . This improves an old upper bound on the ramsey number of the n-cube due to Beck, and brings us closer toward the bound conjectured by Burr and Erdős. Applying the probabilistic method
we also show that for all and there exists a bipartite graph with n vertices and maximum degree at most whose ramsey number is greater than for some absolute constant c>1.
Received December 1, 1999
RID="*"
ID="*" Supported by NSF grant DMS-9704114
RID="**"
ID="**" Supported by KBN grant 2 P03A 032 16 相似文献
20.
In this paper we develop a method for classifying an unknown data vector as belonging to one of several classes. This method
is based on the statistical methods of maximum likehood and borrowed strength estimation. We develop an MPEC procedure (for
Mathematical Program with Equilibrium Constraints) for the classification of a multi-dimensional observation, using a finite
set of observed training data as the inputs to a bilevel optimization problem. We present a penalty interior point method
for solving the resulting MPEC and report numerical results for a multispectral minefield classification application. Related
approaches based on conventional maximum likehood estimation and a bivariate normal mixture model, as well as alternative
surrogate classification objective functions, are described.
Received: October 26, 1998 / Accepted: June 11, 2001?Published online March 24, 2003
RID="***"
ID="***"The authors of this work were all partially supported by the Wright Patterson Air Force Base via Veda Contract F33615-94-D-1400.
The first and third author were also supported by the National Science Foundation under grant DMS-9705220.
RID="*"
ID="*"The work of this author was based on research supported by the U.S. National Science Foundation under grant CCR-9624018.
RID="**"
ID="**"The work of this author was supported by the Office of Naval Research under grant N00014-95-1-0777. 相似文献