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1.
Let Θ = (θ 1,θ 2,θ 3) ∈ ℝ3. Suppose that 1, θ 1, θ 2, θ 3 are linearly independent over ℤ. For Diophantine exponents
$\begin{gathered} \alpha (\Theta ) = sup\left\{ {\gamma > 0: \mathop {\lim }\limits_{t \to } \mathop {\sup }\limits_{ + \infty } t^\gamma \psi _\Theta (t) < + \infty } \right\}, \hfill \\ \beta (\Theta ) = sup\left\{ {\gamma > 0: \mathop {\lim }\limits_{t \to } \mathop {\inf }\limits_{ + \infty } t^\gamma \psi _\Theta (t) < + \infty } \right\} \hfill \\ \end{gathered}$\begin{gathered} \alpha (\Theta ) = sup\left\{ {\gamma > 0: \mathop {\lim }\limits_{t \to } \mathop {\sup }\limits_{ + \infty } t^\gamma \psi _\Theta (t) < + \infty } \right\}, \hfill \\ \beta (\Theta ) = sup\left\{ {\gamma > 0: \mathop {\lim }\limits_{t \to } \mathop {\inf }\limits_{ + \infty } t^\gamma \psi _\Theta (t) < + \infty } \right\} \hfill \\ \end{gathered}  相似文献   

2.
Given a nontrivial Borel measure on ℝ, let p n be the corresponding orthonormal polynomial of degree n whose zeros are λ j (n), j=1,…,n. Then for each j=1,…,n,
with
defines a discrete probability distribution. The Shannon entropy of the sequence {p n } is consequently defined as
In the case of Chebyshev polynomials of the first and second kinds, an explicit and closed formula for is obtained, revealing interesting connections with number theory. In addition, several results of numerical computations exemplifying the behavior of for other families are presented.   相似文献   

3.
Let Ω be an open bounded set in ℝN, N≥3, with connected Lipschitz boundary ∂Ω and let a(x,ξ) be an operator of Leray–Lions type (a(⋅,∇u) is of the same type as the operator |∇u|p−2u, 1<p<N). If τ is the trace operator on ∂Ω, [φ] the jump across ∂Ω of a function φ defined on both sides of ∂Ω, the normal derivative ∂/∂νa related to the operator a is defined in some sense as 〈a(⋅,∇u),ν〉, the inner product in ℝN, of the trace of a(⋅,∇u) on ∂Ω with the outward normal vector field ν on ∂Ω. If β and γ are two nondecreasing continuous real functions everywhere defined in ℝ, with β(0)=γ(0)=0, fL1(ℝN), gL1(∂Ω), we prove the existence and the uniqueness of an entropy solution u for the following problem,
in the sense that, if Tk(r)=max {−k,min (r,k)}, k>0, r∈ℝ, ∇u is the gradient by means of truncation (∇u=DTku on the set {|u|<k}) and , u measurable; DTk(u)∈Lp(ℝN), k>0}, then and u satisfies,
for every k>0 and every . Mathematics Subject Classifications (2000)  35J65, 35J70, 47J05.  相似文献   

4.
For a continuous almost periodic function , we show that the function
where the supremum is taken over all solutions of the system of differential inclusion , , has the following limit (as μ→+0):
, Thus if the parameter μ is small, then and the limit of the maximal mean can approximately be determined by solving problems of smaller dimensionality. Moreover, if the compact sets and are nondegenerate, then Ψ f is independent of initial data. Translated fromMatematicheskie Zametki, Vol. 66, No. 3, pp. 431–438, September, 1999.  相似文献   

5.
We study the existence and multiplicity of positive solutions for the inhomogeneous Neumann boundary value problems involving the p(x)-Laplacian of the form
where Ω is a bounded smooth domain in , and p(x) > 1 for with and φ ≢ 0 on ∂Ω. Using the sub-supersolution method and the variational method, under appropriate assumptions on f, we prove that, there exists λ* > 0 such that the problem has at least two positive solutions if λ = λ*, has at least one positive solution if λ = λ*, and has no positive solution if λ = λ*. To prove the result we establish a special strong comparison principle for the Neumann problems. The research was supported by the National Natural Science Foundation of China 10371052,10671084).  相似文献   

6.
We present more general forms of the mean-value theorems established before for multiplicative functions on additive arithmetic semigroups and prove, on the basis of these new theorems, extensions of the Elliott-Daboussi theorem. Let be an additive arithmetic semigroup with a generating set ℘ of primes p. Assume that the number G(m) of elements a in with “degree” (a)=m satisfies
with constants q>1, ρ 1<ρ 2<⋅⋅⋅<ρ r =ρ, ρ≥1, γ>1+ρ. For the main result, let α,τ,η be positive constants such that α>1,τ ρ≥1, and τ α ρ≥1. Then for a multiplicative function f(a) on the following two conditions (A) and (B) are equivalent. These are (A) All four series
converge and
and (B) The order τ ρ mean-value
exists with m f ≠0 and the limit
exists with M v (α)>0.   相似文献   

7.
This paper summarized recent achievements obtained by the authors about the box dimensions of the Besicovitch functions given byB(t) := ∞∑k=1 λs-2k sin(λkt),where 1 < s < 2, λk > 0 tends to infinity as k →∞ and λk satisfies λk 1/λk ≥λ> 1. The results show thatlimk→∞ log λk 1/log λk = 1is a necessary and sufficient condition for Graph(B(t)) to have same upper and lower box dimensions.For the fractional Riemann-Liouville differential operator Du and the fractional integral operator D-v,the results show that if λ is sufficiently large, then a necessary and sufficient condition for box dimension of Graph(D-v(B)),0 < v < s - 1, to be s - v and box dimension of Graph(Du(B)),0 < u < 2 - s, to be s uis also lim k→∞logλk 1/log λk = 1.  相似文献   

8.
The asymptotic expressions of the covariance matrices for both the least square estimates L α T and Markov (best linear) estimates are obtained, based on a sample in a finite interval (0, T) of the regression co-efficients α = (α 1, …, α m 0)′ of a parameter-continuous process with a stationary residual. We assume that the regression variables φ ν(t), t ⩾ 0, ν = 1, …, m 0, are continuous in t, and satisfy conditions (3.1)–(3.3). For the residual, we assume that it is a stationary process that possesses a bounded continuous spectral density f(λ). Under these assumptions, it is proven that
where the matrices D T , B(0), α(λ) are defined in Section 3. Under the assumptions mentioned above, if, furthermore, there exist some positive integer m and a constant C such that g(λ)(1 + λ 2)mC > 0, where g(λ) is the spectral density of the residual, and for every N > 0,
converge uniformly in h, l ∈ (−N, N), then the following formula holds.
The asymptotic equivalence of the least square estimates and the Markov estimates is also discussed. Translated by Wang Ting from the Chinese version of the paper published in Journal of Beijing Normal University (Natural Sciences), 1965, 1: 15–44  相似文献   

9.
If a monoid S is given by some finite complete presentation ℘, we construct inductively a chain of CW-complexes
such that Δ n has dimension n, for every 2≤mn, the m-skeleton of Δ n is Δ m , and p m are critical (m+1)-cells with 1≤mn−2. For every 2≤mn−1, the following is an exact sequence of (ℤS,ℤS)-bimodules
where if m=2. We then use these sequences to obtain a free finitely generated bimodule partial resolution of ℤS. Also we show that for groups properties FDT and FHT coincide.  相似文献   

10.
Abstract   Let ξ i ∈ (0, 1) with 0 < ξ1 < ξ2 < ··· < ξ m−2 < 1, a i , b i ∈ [0,∞) with and . We consider the m-point boundary-value problem
where f(x, y) ≥ −M, and M is a positive constant. We show the existence and multiplicity of positive solutions by applying the fixed point theorem in cones. *Supported by the NSFC (10271095). GG-110-10736-1003, NWNU-KJCXGC-212 and the Foundation of Major Project of Science and Technology of Chinese Education Ministry  相似文献   

11.
We establish the global existence and decaying results for the Cauchy problem of nonlinear evolution equations,
(1)
. for initial data with different end states,
(2)
which displays the complexity in between ellipticity and dissipation. Due to smoothing effect of the parabolic operator, we detail the regularity property and estimates when t > 0 for the higher order spatial derivatives despite its relatively lower regularity of the initial data. Also we discuss the decay estimates without the restriction of L 1 bound as in Tang and Zhao [17], Wang [20]. Related to recent work by [15], our derivation may also establish the same estimates directly if under the same condition. Work supported by NSERC (Canada).  相似文献   

12.
Let G be a multigraph. The star number s(G) of G is the minimum number of stars needed to decompose the edges of G. The star arboricity sa(G) of G is the minimum number of star forests needed to decompose the edges of G. As usual λK n denote the λ-fold complete graph on n vertices (i.e., the multigraph on n vertices such that there are λ edges between every pair of vertices). In this paper, we prove that for n ⩾ 2
((1))
((2))
  相似文献   

13.
This paper deals with the existence of weak solutions in W 01(Ω) to a class of elliptic problems of the form
in a bounded domain Ω of ℝ N . Here a satisfies
for all ξ∈ℝ N , a.e. x∈Ω, , h 1L loc 1(Ω), h 1(x)1 for a.e. x in Ω; λ 1 is the first eigenvalue for −Δ p on Ω with zero Dirichlet boundary condition and g, h satisfy some suitable conditions.   相似文献   

14.
15.
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   

16.
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   

17.
Let β 0=0.308443… denote the Littlewood-Salem-Izumi number, i.e., the unique solution of the equation
In this paper it is proved that if a 0a 1⋅⋅⋅a n >0 and , k≥1 then for all θ∈(0,π)
and furthermore, the number β 0 is best possible in the sense that for any β∈(0,β 0)
where the coefficients c k (β) are defined as
Results for the sine sums are obtained as well. These results generalize and sharpen the well known trigonometric inequalities of Vietoris. This research was supported by a grant from the Australian Research Council. The second author was also supported in part by the NSERC Canada under grant G121211001. The third author was also supported in part by the NSFC of China under grant 10471010.  相似文献   

18.
For a Young function φ and a Borel probability measure m on a compact metric space (T,d) the minorizing metric is defined by
In the paper we extend the result of Kwapien and Rosinski (Progr. Probab. 58, 155–163, 2004) relaxing the conditions on φ under which there exists a constant K such that
for each separable process X(t), tT which satisfies . In the case of φ p (x)≡x p , p≥1 we obtain the somewhat weaker results. Partially supported by the Funds of Grant MENiN 1 P03A 01229.  相似文献   

19.
Let Sk(Γ) be the space of holomorphic Γ-cusp forms f(z) of even weight k ≥ 12 for Γ = SL(2, ), and let Sk(Γ)+ be the set of all Hecke eigenforms from this space with the first Fourier coefficient af(1) = 1. For f ∈ Sk(Γ)+, consider the Hecke L-function L(s, f). Let
It is proved that for large K,
where ε > 0 is arbitrary. For f ∈ Sk(Γ)+, let L(s, sym 2 f) denote the symmetric square L-function. It is proved that as k → ∞ the frequence
converges to a distribution function G(x) at every point of continuity of the latter, and for the corresponding characteristic function an explicit expression is obtained. Bibliography: 17 titles. __________ Translated from Zapiski Nauchnykh Seminarov POMI, Vol. 314, 2004, pp. 221–246.  相似文献   

20.
Realization of Boolean functions in the class of oriented contact circuits (OCCs) with certain restrictions on the weight, number, and types of adjacent contacts is studied. Oriented contact circuits are considered in which, from an arbitrary vertex, at most λ arcs issue and at most ν different Boolean variables are used in the marks of the issuing arcs. The weight of a vertex of an OCC is defined as being equal to λ if one arc enters a vertex and equal to λ(1 + ω), where ω > 0, otherwise. Then, as usual, the weight of an OCC is defined as the sum of the weights of its vertices; the weight of a Boolean function, as the minimum weight of OCCs realizing it; and Shannon function W λ, ν, ω(n), as the maximum weight of the Boolean function of n variables. For this Shannon function, the so-called high-accuracy bound
$ W_{\lambda ,v,\omega } (n) = \frac{\lambda } {{\lambda - 1}}\frac{{2^n }} {n}\left( {1 + \frac{{\frac{{2\lambda - v - 2}} {{\lambda - 1}}\log n \pm O(1)}} {n}} \right), $ W_{\lambda ,v,\omega } (n) = \frac{\lambda } {{\lambda - 1}}\frac{{2^n }} {n}\left( {1 + \frac{{\frac{{2\lambda - v - 2}} {{\lambda - 1}}\log n \pm O(1)}} {n}} \right),   相似文献   

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