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1.
Résumé Soitq un nombre algébrique de module 1, qui ne soit pas une racine de l'unité, etP [X, Y 0,Y 1] un polynôme non nul. Dans cet article, nous montrons que toute solution de l'équation fonctionnelleP(z, (z), (qz))=0, qui est une série formelle (z) dansQ[[z]], a un rayon de convergence non nul.
Summary Letq Q be an algebraic number of modulus one that is not a root of unity. LetP Q[X, Y 0,Y 1] be a non zero polynomial. In this paper, we show that every formal power series,(z) Q[[z]], solution of the functional equationP(z), (z), (qz)) = 0 has a non zero radius of convergence.
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2.
While several micromechanical models have been developed today in the literature for two-phase media, the extent of their applicability to multiphase materials need yet to be investigated. The present paper studies the effective thermal conductivity of multicomponent composites, and concentrates on two methods: (a) the Mori-Tanaka model, (b) The generalized self-consistent scheme. The Mori-Tanaka method of back-stress previously developed in the context of elasticity of composites is applied here to the conduction problem. The generalized self-consistent scheme, based on a particle-matrix embedding in the effective medium, is studied in this paper in the context of multicomponent media and two variations of this method distinctly different in their imbedding procedure are proposed.Numerical results are given for three-phase composites illustrating and comparing the proposed methods.
Resumé Plusieurs modéles de micromécanique existent aujoud'hui dans la litérature des matériaux á deux phases. L'applicabilité de ces modéles aux matériaux á multi-phases nécessite d'autre part d'être examinée. Ce travail étudie la conductivité thermale des matériaux á multi-phases et se concentre sur deux méthodes: a) le modéle de Mori-Tanaka b) la méthode auto-consistante généralisée. La méthode de Mori-Tanaka, développée auparavant dans le cadre des propriétés mécaniques des composites est appliquée ici au probléme de conduction. La méthode autoconsistante généralisée est étudiée dans le cadre des matériaux á multi-phases et deux alternatives de cette méthode distinctement différentes dans leur formalisme sont proposées. Pour des matériaux á trois phases on donne des resultats numériques qui illustrent et comparent les méthodes proposées.
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3.
Résumé SoitG un groupe moyennable connexe, locallement compact, à base dénombrable. Soit une mesure positive sur les boréliens deG. Nous étudions les fonctions boréliennes positivesh vérifiant: g G, . Sous de bonnes hypothèses sur , nous obtenons, pour ces fonctions, une représentation intégrale à l'aide d'exponentielles.
Summary LetG be a connected locally compact separable amenable group. Let be a positive measure on the Borel -field ofG. We study the positive Borel functionsh onG which satisfy: g G, . Under smooth assumptions on , we establish an integral representation of these functions in term of exponentials.
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4.
We prove a local limit theorem (LLT) on Cramer-type large deviations for sums S V = t V ( t ), where t , t Z , 1, is a Markov Gaussian random field, V Z , and is a bounded Borel function. We get an estimate from below for the variance of S V and construct two classes of functions , for which the LLT of large deviations holds.  相似文献   

5.
, , . . . [1], , . , , ., , L logL. , , . . . . [5]. , .  相似文献   

6.
We study the regularity of the minimizer u for the functional F (u,f)=|u|2 + |u–f{2 over all maps uH 1(, S 2). We prove that for some suitable functions f every minimizer u is smooth in if 0 and for the same functions f, u has singularities when is large enough.
Résumé On étudie la régularité des minimiseurs u du problème de minimisation minueH 1(,S2)(|u|2 + |u–f{2. On montre que pour certaines fonctions f, u est régulière lorsque 0 et pour les mêmes f, si est assez grand, alors u possède des singularités.
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7.
One considers singular parabolic equations of the form (u)/t–u0,where sign u is a multivalued function, equal to -I for u<0, to 1 for u>0, and to the segment [-I,I] for u=0. Such a class of equations contains, in particular, the model for the two-phase Stefan problem, the porous medium equation, and the plasma equation. For the bounded generalized solutions u(x,t) of the indicated equations (without the assumption u/L2one has established a qualified local estimate of the modulus of continuity.Translated from Zapiski Nauchnykh Seminarov Leningradskogo Otdeleniya Matematicheskogo Ins'tituta im. V. A. Steklova AN SSSR, Vol. 147, pp. 49–71, 1985.  相似文献   

8.
. ( ), R n L 2(R 2).

The author is supported by the National Natural Science Found of China.  相似文献   

9.
If X is a real Banach space, then the inequality x defines so-called hyperbolic cone in E=X. We develop a relevant version of Perron-Frobenius-Krein-Rutman theory.  相似文献   

10.
Summary In this paper we present a general theory for discrete Newton methods, iterated defect corrections via neighbouring problems and deferred corrections based on asymptotic expansions of the discretization error.Dedicated to Professor Dr. J. Weisinger on the occasion of his sixty-fifth birthday  相似文献   

11.
We propose a new measure of conditioning for the exponential of a block triangular matrix. We also show that different condition numbers must be used to assess the accuracy of different algorithms which implement diagonal Padé with scaling and squaring.  相似文献   

12.
We obtain the analytic expression for the total cross section of the reaction e e +l l + (l=,) taking possible quasianapole interaction effects into account. We find numerical restrictions on the interaction parameter value from data for the reaction e e ++ in the energy domain below the Z 0 peak.  相似文献   

13.
, . . Q k [0,2],k=1,2, — . F(x, y)L(T), T=[0, 2]2, G(x, y)L(T) , G(x,y)=F(x,y) Q=Q 1 ×Q 2 - .  相似文献   

14.
Bruno Kahn 《K-Theory》1991,5(6):555-566
Let F be a field, G F its absolute Galois group, : G FGL(C) a continuous complex representation of G F and c i() H2i(F, Z) its Chern classes. We show, under a mild assumption on F. that c i ()=0 for all i2. For general F, one has that 2ci ()=0 for all i 2.
Cette dernière condition résulte en fait de la continuité de .  相似文献   

15.
LetX, Y be finite sets and suppose thatF is a collection of pairs of sets (F, G),FX,GY satisfying |FF|s, |GG|t and |FF|+|GG|s+t+1 for all (F, G),F, GF. Extending a result of Sali, we determine the maximum ofF.  相似文献   

16.
(C, ). , . 0<<1. 1) - ( k ), k =a k , (C, ), . 2) , , (C, ) ; k = =¦a k ¦.  相似文献   

17.
Let A be the generator of a C0-semigroup {T(t); t0} defined on a Banach lattice E. It is shown that T(t) is a lattice homomorphism for all t>0 if and only if A satisfies <¦x¦, Ax>= (xD(A), x D(A)) (where q: EE is the evaluation mapping). This equality is used to obtain a spectral decomposition for generators of positive groups.  相似文献   

18.
In this paper we show that the existence of plane partitions, which are minimal in a sense to be defined, yields minimal irreducible summands in the Kronecker product of two irreducible characters of the symmetric group S(n). The minimality of the summands refers to the dominance order of partitions of n. The multiplicity of a minimal summand equals the number of pairs of Littlewood-Richardson multitableaux of shape (, ), conjugate content and type . We also give lower and upper bounds for these numbers.  相似文献   

19.
20.
The series 1 n r–1 J n (n)J n (n) (r 0, 0 < 1) arise in studying the emission and absorption of radiation by a charged particle on a Kepler orbit. For the first few even,r, the sums are obtained in closed form, and for oddr they are given in terms of a certain definite integral. The integral is expressed as a power series in for ||<1, and, near =1, an asymptotic expansion in powers of (1–2)1/2 may be obtained.
Résumé La série 1 n r–1 J n (n)J n (n) (r 0, 0 < 1) se trouve par l'émission et l'absorption du rayonnement d'une particule chargée sur l'orbite Keplerien. Pour les plus petites valuers paires der, les sommes s'obtienment en forme compacte, et pour les valuers impaires, elles se déterminent d'après une intégrale definie. Pour ||<1, cette intégrale se développe dans une série de puissances de , et dans le voisinage de =1, on obtient une série asymptotique et puissances de (1–2)1/2.
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