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971.
Mitrofan M. Choban 《Topology and its Applications》2008,155(8):787-796
In the present article many theorems about existence of continuous selections for a set-valued mapping into the metrizable spaces are extended to mappings into non-metrizable spaces. 相似文献
972.
We propose different nonparametric tests for multivariate data and derive their asymptotic distribution for unbalanced designs in which the number of factor levels tends to infinity (large a, small ni case). Quasi gratis, some new parametric multivariate tests suitable for the large a asymptotic case are also obtained. Finite sample performances are investigated and compared in a simulation study. The nonparametric tests are based on separate rankings for the different variables. In the presence of outliers, the proposed nonparametric methods have better power than their parametric counterparts. Application of the new tests is demonstrated using data from plant pathology. 相似文献
973.
The Ulm method is considered to approximate a solution of a nonlinear operator equation F(x) = 0. We study the convergence of this method when F′ is ω-conditioned and prove that the R-order of convergence is at least 1 + p if ω is quasi-homogeneous of type ω(tz)≤ t
p
ω(z), for z > 0, tϵ[0,1] and pϵ[0,1].
Preparation of this paper was partly supported by the Ministry of Education and Science (MTM 2005-03091). 相似文献
974.
A group G is said to satisfy the maximal permutizer condition if the permutizer of any maximal subgroup M of G in G, PG(M), is G. In this paper, we characterize the supersolubility of finite groups by using the maximal permutizer condition. We also get some results for when both G/N and N are supersoluble, which implies that G is supersoluble. Our results unify or generalize some known results. 相似文献
975.
Li Yin Xiaojing Xu Hongjun Yuan 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》2008,59(3):457-474
The aims of this paper are to discuss global existence and uniqueness of solution for a class of non-Newtonian fluids with
vacuum in one-dimensional bounded interval. The important point in this paper is that we allow the initial vacuum. In particular,
these results are used to prove similar results for more general non-Newtonian fluids, and applied to numerical computation.
This work is partially supported by the 985 program of Jilin University, China Postdoctoral Sciences Foundation, and NSF Grant
([10571072]; [10601009]). 相似文献
976.
Y. Fırat Çelikler 《Mathematische Zeitschrift》2008,259(3):681-695
We study the commutative algebra of rings of separated power series over a ring E and that of their extensions: rings of separated (and more specifically convergent) power series from a field K with a separated E-analytic structure. Both of these collections of rings already play an important role in the model theory of non-Archimedean
valued fields and we establish their algebraic properties. This will make a study of the analytic geometry over such fields
through the classical methods of algebraic geometry possible. 相似文献
977.
Clement Durringer Raphael Hauser Heinrich Matzinger 《Stochastic Processes and their Applications》2008
The problem of sequence comparison via optimal alignments occurs naturally in many areas of applications. The simplest such technique is based on evaluating a score given by the length of a longest common subsequence divided by the average length of the original sequences. In this paper we investigate the expected value of this score when the input sequences are random and their length tends to infinity. The corresponding limit exists but is not known precisely. We derive a theoretical large deviation, convex analysis and Monte Carlo based method to compute a consistent sequence of upper bounds on the unknown limit. An empirical practical version of our method produces promising numerical results. 相似文献
978.
Motivated by Khovanov homology and relations between the Jones polynomial and graph polynomials, we construct a homology theory for embedded graphs from which the chromatic polynomial can be recovered as the Euler characteristic. For plane graphs, we show that our chromatic homology can be recovered from the Khovanov homology of an associated link. We apply this connection with Khovanov homology to show that the torsion-free part of our chromatic homology is independent of the choice of planar embedding of a graph. We extend our construction and categorify the Bollobás-Riordan polynomial (a generalization of the Tutte polynomial to embedded graphs). We prove that both our chromatic homology and the Khovanov homology of an associated link can be recovered from this categorification. 相似文献
979.
Miles Holloway 《Archiv der Mathematik》2008,90(4):311-316
We answer a question raised in [9] by showing the equality of two different definitions of rank variety for finitely generated
modules over truncated polynomial algebras. We do this by establishing an isomorphism of algebras used in the two definitions
of rank variety.
Received: 23 April 2007 相似文献