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1.
We reconsider the boundary-layer flow of a non-Newtonian fluid corresponding to the classical Ostwald de Waele power-law model. The physical problem can be described in terms of solutions of the degenerate differential equation
posed on the interval (0, ∞), in which β < 0 and the real number (the power law index) n ≥ 1. This paper deals with the asymptotic behavior of any global unbounded solution; that is a solution satisfying
. Received: 8 March 2006 Revised: 8 January 2007  相似文献   

2.
Consider a plate occupying in a reference configuration a bounded open set Ω ⊂ ℝ 2 , and let be its stored-energy function. In this paper we are concerned with relaxation of variational problems of type:
, where with is the scalar product in ℝ 3 and is the external loading per unit surface. We take into account the fact that an infinite amount of energy is required to compress a finite surface of the plate into zero surface, i.e.,
Mathematics Subject Classification (2000) 49J45  相似文献   

3.
Cubic elliptic functions   总被引:1,自引:1,他引:0  
The function
occurs in one of Ramanujan’s inversion formulas for elliptic integrals. In this article, a common generalization of the cubic elliptic functions
is given. The function g1 is the derivative of Ramanujan’s function Φ (after rescaling), and χ3(n) = 0, 1 or −1 according as n≡ 0, 1 or 2 (mod 3), respectively, and |q| < 1. Many properties of the common generalization, as well as the functions g1 and g2, are proved. 2000 Mathematics Subject Classification Primary—33E05; Secondary—11F11, 11F27  相似文献   

4.
In the present paper, we derive the Laplace transforms of the integral functionals
and
where p and q are real numbers, {B t (μ) : t ≥ 0} is a Brownian motion with drift μ > 0 (denoted BM(μ)), and {R t (3) : t ≥ 0} is a 3-dimensional Bessel process (denoted BES(3)). The transforms are given in terms of Gauss' hypergeometric functions, and the results are closely related to some results for functionals of Jacobi diffusions. This work generalizes and completes some results of Donati-Martin and Yor and Salminen and Yor. Bibliography: 18 titles. __________ Published in Zapiski Nauchnykh Seminarov POMI, Vol. 311, 2004, pp. 51–78.  相似文献   

5.
Let Δ(x) denote the error term in the Dirichlet divisor problem, and E(T) the error term in the asymptotic formula for the mean square of . If E *(t)=E(t)-2πΔ*(t/2π) with , then we obtain
and
It is also shown how bounds for moments of | E *(t)| lead to bounds for moments of .  相似文献   

6.
Suppose thatА is a nonnegative self-adjoint extension to { } of the formal differential operator−Δu+q(x)u with potentialq(x) satisfying the condition {
} or the condition {
} in which the nonnegative function itχ(r) is such that { }. For each α∈(0, 2], we establish an estimate of the generalized Fourier transforms of an arbitrary function { } of the form {
} If, in addition, { }, then, along with this estimate, a similar lower bound is established. Translated fromMatematicheskie Zametki, Vol. 65, No. 4, pp. 542–551, April, 1999.  相似文献   

7.
The paper presents an error bound of the Ritz method for the problem of minimizing the functional
in the space in the case where the standard assumption on the continuity of q(t) is replaced by the condition q2(t)t(1-t) L(0,1). In the case where q(t) is continuous, the new bound is sharper than the known one. Bibliography: 5 titles. Translated from Zapiski Nauchnykh Seminarov POMI, Vol. 359, 2008, pp. 208–215.  相似文献   

8.
In this paper, we study certain polylogarithmic double series
where p, q, r are nonnegative integers and x is any complex number with
. First we give certain polylogarithmic interpolation formulas of the results of Mordell, Subbarao-Sitaramachandrarao and Zagier. By specializing to x = 1, we can obtain their results. Secondly we calculate some special values of these polylogarithmic double series. Received: 21 November 2005; Revised: 8 May 2006  相似文献   

9.
Let u=u(x,t,uo)represent the global solution of the initial value problem for the one-dimensional fluid dynamics equation ut-εuxxt+δux+γHuxx+βuxxx+f(u)x=αuxx,u(x,0)=uo(x), whereα〉0,β〉0,γ〉0,δ〉0 andε〉0 are constants.This equation may be viewed as a one-dimensional reduction of n-dimensional incompressible Navier-Stokes equations. The nonlinear function satisfies the conditions f(0)=0,|f(u)|→∞as |u|→∞,and f∈C^1(R),and there exist the following limits Lo=lim sup/u→o f(u)/u^3 and L∞=lim sup/u→∞ f(u)/u^5 Suppose that the initial function u0∈L^I(R)∩H^2(R).By using energy estimates,Fourier transform,Plancherel's identity,upper limit estimate,lower limit estimate and the results of the linear problem vt-εv(xxt)+δvx+γHv(xx)+βv(xxx)=αv(xx),v(x,0)=vo(x), the author justifies the following limits(with sharp rates of decay) lim t→∞[(1+t)^(m+1/2)∫|uxm(x,t)|^2dx]=1/2π(π/2α)^(1/2)m!!/(4α)^m[∫R uo(x)dx]^2, if∫R uo(x)dx≠0, where 0!!=1,1!!=1 and m!!=1·3…(2m-3)…(2m-1).Moreover lim t→∞[(1+t)^(m+3/2)∫R|uxm(x,t)|^2dx]=1/2π(x/2α)^(1/2)(m+1)!!/(4α)^(m+1)[∫Rρo(x)dx]^2, if the initial function uo(x)=ρo′(x),for some functionρo∈C^1(R)∩L^1(R)and∫Rρo(x)dx≠0.  相似文献   

10.
Let τ(n) be the Ramanujan τ-function, x ≥ 10 be an integer parameter. We prove that
We also show that
where ω(n) is the number of distinct prime divisors of n and p denotes prime numbers. These estimates improve several results from [6, 9]. Received: 23 November 2006  相似文献   

11.
We prove that if f belongs to the Morrey space , with λ ∊ [0, n−2], and u is the solution of the problem
then Du belongs to the space , for any Mathematics Subject Classification (2000) 35J25, 35D10  相似文献   

12.
Let be the generalized integers n j associated with a set of generalized primes p i in Beurling’s sense. On the basis of the general mean-value theorems, established in our previous work, for multiplicative function f(n j ) defined on , we prove extensions, in functional form and in mean-value form, of the Elliott–Daboussi theorem to high order mean-values. For the main result, let α,ρ, and τ be positive real constants such that α > 1,ρ≥1 and . Then a multiplicative function f satisfies the following conditions, with some constant , (1) All four series
converge and (2)
if and only if the order τρ mean-value
exists with and the limit
exists with . The proof is deduced from an intrinsic connection between m f and . An erratum to this article can be found at  相似文献   

13.
It is proved that if P(D) is a regular, almost hypoelliptic operator and
$ L_{2,\delta } = \left\{ {u:\left\| u \right\|_{2,\delta } = \left[ {\int {\left( {|u(x)|e^{ - \delta |x|} } \right)^2 dx} } \right]^{1/2} < \infty } \right\},\delta > 0, $ L_{2,\delta } = \left\{ {u:\left\| u \right\|_{2,\delta } = \left[ {\int {\left( {|u(x)|e^{ - \delta |x|} } \right)^2 dx} } \right]^{1/2} < \infty } \right\},\delta > 0,   相似文献   

14.
In this paper, we discuss the moving-average process Xk = ∑i=-∞ ^∞ ai+kεi, where {εi;-∞ 〈 i 〈 ∞} is a doubly infinite sequence of identically distributed ψ-mixing or negatively associated random variables with mean zeros and finite variances, {ai;-∞ 〈 i 〈 -∞) is an absolutely solutely summable sequence of real numbers.  相似文献   

15.
Let Δ(x) denote the error term in the Dirichlet divisor problem, and E(T) the error term in the asymptotic formula for the mean square of . If with , then we obtain
. We also show how our method of proof yields the bound
, where T 1/5+εGT, T<t 1<...<t R ≤2T, t r +1t r ≥5G (r=1, ..., R−1).  相似文献   

16.
This article deals with a semilinear elliptic equation arising in a model for flame propagation outside a compact subset of , for n≥ 2. Our aim is to prove various kind of existence, nonexistence, uniqueness, monotonicity properties and singular limit results for the solutions T of the following Dirichlet problem in :
Mathematics Subject Classification (2000) 35J60, 35K57, 35B25, 80A25 Part of this work was carried out while the author visited the Centen émile Borel for the trimester “Dynamics of Fronts” at the Institut Henri Poincaré, Paris.  相似文献   

17.
Besides other things we prove that if , , locally minimizes the energy
, with N-functions a  ≤ b having the Δ2-property, then . Moreover, the condition
for all large values of t implies . If n = 2, then these results can be improved up to for all s < ∞ without the hypothesis . If n ≥ 3 together with M = 1, then higher integrability for any exponent holds under more restrictive assumptions than .   相似文献   

18.
In this paper, the authors present some new results for the oscillation of the second order nonlinear neutral differential equations of the form
. Easily verifiable criteria are obtained that are also new for differential equations without neutral term i.e. for p(t)≡0.  相似文献   

19.
This paper deals with the solvability of the boundary value problem
where p ∈ (1, ∞) is fixed, is convex, proper, lower semicontinuous, is a Carathéodory mapping and . Received: 12 February 2007  相似文献   

20.
Let→b=(b1,b2,…,bm),bi∈∧βi(Rn),1≤I≤m,βi>0,m∑I=1βi=β,0<β<1,μΩ→b(f)(x)=(∫∞0|F→b,t(f)(x)|2dt/t3)1/2,F→b,t(f)(x)=∫|x-y|≤t Ω(x,x-y)/|x-y|n-1 mΠi=1[bi(x)-bi(y)dy.We consider the boundedness of μΩ,→b on Hardy type space Hp→b(Rn).  相似文献   

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