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151.
Reduced rank regression assumes that the coefficient matrix in a multivariate regression model is not of full rank. The unknown rank is traditionally estimated under the assumption of normal responses. We derive an asymptotic test for the rank that only requires the response vector have finite second moments. The test is extended to the nonconstant covariance case. Linear combinations of the components of the predictor vector that are estimated to be significant for modelling the responses are obtained. 相似文献
152.
J. D. Fanning 《Aequationes Mathematicae》1994,47(2-3):143-149
Summary We prove the following two non-existence theorems for symmetric balanced ternary designs. If 1 = 1 and 0 (mod 4) then eitherV = + 1 or 42 – + 1 is a square and (42 – + 1) divides 2 – 1. If 1 = 2 thenV = ((m + 1)/2)
2 + 2,K = (m
2 + 7)/4 and = ((m – 1)/2)2 + 1 wherem 3 (mod 4). An example belonging to the latter series withV = 18 is constructed. 相似文献
153.
Irene Fonseca David Kinderlehrer Pablo Pedregal 《Calculus of Variations and Partial Differential Equations》1994,2(3):283-313
In this paper we deal with energy functionals depending on elastic strain and chemical composition and we obtain lower semicontinuity results, existence theorems and relaxation in the spacesH
1,p(; n)×L
q
(; d) with respect to weak convergence. Our proofs use parametrized measures associated with weakly converging sequences.The research was partially supported by the National Science Foundation under Grants No. DMS-9000133 and DMS-9201215 and also by the Army Research Office and the National Science Foundation through the Center for Nonlinear Analysis.The research was partially supported by the National Science Foundation uncer Grants No. DMs 911572, the AFOSR 91 0301, the ARO DAAL03 92 G 003 and also by the ARO and the NSF through the Center for Nonlinear Analysis.The research was supported by DGICYT (Spain) through Programa de Perfeccionamiento y Movilidad del Personal Investigador and through grant PB90-0245, by the Army Research Office and the National Science Foundation through the Center for Nonlinear Analysis and also by the project EurHomogenization SC1-CT91-0732 of the European Comunity. 相似文献
154.
J. Deák 《Periodica Mathematica Hungarica》1994,29(3):245-265
We are going to investigate simultaneous extensions of various topological structures (i.e. traces on several subsets at the same time are prescribed), also with separation axioms T0, T1, symmetry (in the sense of Part I, § 3), Riesz property, Lodato property. The following questions will be considered: (i) Under what conditions is there an extension? (ii) How can the finest extension be described? (iii) Is there a coarsest extension? (iv) Can we say more about extensions of two structures than in the general case? (v) Assume that certain subfamilies (e.g. the finite ones) can be extended; does the whole family have an extension, too? The general categorial results from Part I will be applied whenever possible (even they are not really needed). 相似文献
155.
Armando Treibich 《Acta Appl Math》1994,36(1-2):27-48
We construct all tangential covers as zeroes of a particular set of polynomials. The resulting pointed curves give rise, through the Krichever dictionary, to elliptic KP solitons. We then give a criterion to detect the so-called hyperelliptic-tangential covers, which give rise to elliptic KdV solitons. Finally we construct new examples of the latter covers and write down the corresponding (doubly periodic finite-gap) source potentials.Dedicated to the memory of J.-L. Verdier 相似文献
156.
Summary.
In an abstract framework we present a formalism which
specifies the notions of consistency and stability of
Petrov-Galerkin
methods used to approximate nonlinear problems which are, in many
practical situations, strongly nonlinear elliptic problems. This
formalism gives rise to a priori and a posteriori error estimates which
can be used for the refinement of the mesh in adaptive finite element
methods applied to elliptic nonlinear problems. This theory is
illustrated with the example: in a two
dimensional domain with Dirichlet boundary conditions.
Received June 10, 1992 / Revised version received February
28, 1994 相似文献
157.
Pavel Pyrih 《Potential Analysis》1994,3(3):273-281
We study the set of functions in quasi-analytic classes and the set of finely holomorphic functions. We show that no one of these two sets is contained in the other.LetI denote the set of complex functionsf: for which there exists a quasi-analytic classC{M
n} containingf. Let denote the set of complex functionsf: for which there exist a fine domainU containing the real line and a function
finely holomorphic onU satisfyingf(x)=
(x) for allx . The power of unique continuation is incomparable in these two cases (I\ is non-empty, \I is non-empty).Research supported by the grant No. 201/93/2174 of Czech Grant Agency and by the grant No. 354 of Charles University. 相似文献
158.
Summary We study integral functionals of the formF(u, )=
f(u)dx, defined foru C1(;R
k), R
n
. The functionf is assumed to be polyconvex and to satisfy the inequalityf(A) c0¦(A)¦ for a suitable constant c0 > 0, where (A) is then-vector whose components are the determinants of all minors of thek×n matrixA. We prove thatF is lower semicontinuous onC
1(;R
k) with respect to the strong topology ofL
1(;R
k). Then we consider the relaxed functional , defined as the greatest lower semicontinuous functional onL
1(;R
k
) which is less than or equal toF on C1(;R
k). For everyu BV(;R
k) we prove that (u,)
f(u)dx+c0¦Dsu¦(), whereDu=u dx+Dsu is the Lebesgue decomposition of the Radon measureDu. Moreover, under suitable growth conditions onf, we show that (u,)=
f(u)dx for everyu W1,p(;R
k), withp min{n,k}. We prove also that the functional (u, ) can not be represented by an inte- gral for an arbitrary functionu BVloc(R
n;R
k). In fact, two examples show that, in general, the set function (u, ) is not subadditive whenu BVloc(R
n;R
k), even ifu W
loc
1,p
(R
n;R
k) for everyp < min{n,k}. Finally, we examine in detail the properties of the functionsu BV(;R
k) such that (u, )=
f(u)dx, particularly in the model casef(A)=¦(A)¦. 相似文献
159.
Dragomir Ž. Đoković 《Combinatorica》1994,14(3):375-377
No Hadamard matrices of order 956 appear in the literature. In this note we construct two such matrices. They are both of Goethals-Seidel type. As a consequence of this and of a result of Seberry and Yamada, we conclude that there exist 4-Williamson type matrices of order 1913.This work was supported by NSERC of Canada Grants A-5285 and EQP0107539. 相似文献
160.
Reiner Kühnau 《Mathematische Annalen》1994,299(1):779-784
Ohne Zusammenfassung
Im Gedenken an Herbert Grötzsch (1902–1993) 相似文献