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1.
The norm of the operator
(1-2x y+x^2y^2)^(n+)/2,T_{\alpha} f(x):=\int\limits_{\mathbb{B}^n} \frac{f(y) dV_{\alpha}(y)}{(1-2x\cdot y+|x|^2|y|^2)^{(n+\alpha)/2}},  相似文献   

2.
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   

3.
Approximation to the function |x| plays an important role in approximation theory. This paper studies the approximation to the function xαsgn x, which equals |x| if α = 1. We construct a Newman Type Operator rn(x) and prove max |x|≤1|xαsgn x-rn(x)|~Cn1/4e-π1/2(1/2)αn.  相似文献   

4.
In a loaded Jacobi space with the inner product
$ \left\langle {f,g} \right\rangle = \frac{{\Gamma (\alpha + \beta + 2)}}{{2^{\alpha + \beta + 1} \Gamma (\alpha + 1)\Gamma (\beta + 1)}}\smallint _{ - 1}^1 fg(1 - x)^\alpha (1 + x)^\beta dx + Lf(1)g(1) + Mf( - 1)g( - 1)(L,M \ge 0) $ \left\langle {f,g} \right\rangle = \frac{{\Gamma (\alpha + \beta + 2)}}{{2^{\alpha + \beta + 1} \Gamma (\alpha + 1)\Gamma (\beta + 1)}}\smallint _{ - 1}^1 fg(1 - x)^\alpha (1 + x)^\beta dx + Lf(1)g(1) + Mf( - 1)g( - 1)(L,M \ge 0)   相似文献   

5.
We present integral versions of some recently proved results which improve the Jensen-Steffensen and related inequalities for superquadratic functions. For superquadratic functions which are not convex we get inequalities analogous to the integral Jensen-Steffensen inequality for convex functions. Therefore, we get refinements of all the results which use only the convexity of these functions. One of the inequalities that we obtain for a superquadratic function φ is
$ \bar y \geqslant \phi \left( {\bar x} \right) + \frac{1} {{\lambda \left( \beta \right) - \lambda \left( \alpha \right)}}\int_\alpha ^\beta {\phi \left( {\left| {f\left( t \right) - \bar x} \right|} \right)d\lambda \left( t \right)} $ \bar y \geqslant \phi \left( {\bar x} \right) + \frac{1} {{\lambda \left( \beta \right) - \lambda \left( \alpha \right)}}\int_\alpha ^\beta {\phi \left( {\left| {f\left( t \right) - \bar x} \right|} \right)d\lambda \left( t \right)}   相似文献   

6.
Zeta-generalized-Euler-constant functions,
$ \gamma \left( s \right): = \sum\limits_{k = 1}^\infty {\left( {\frac{1} {{k^s }} - \int_k^{k + 1} {\frac{{dx}} {{x^s }}} } \right)} $ \gamma \left( s \right): = \sum\limits_{k = 1}^\infty {\left( {\frac{1} {{k^s }} - \int_k^{k + 1} {\frac{{dx}} {{x^s }}} } \right)}   相似文献   

7.
Let Θ be a bounded open set in ℝ n , n ⩾ 2. In a well-known paper Indiana Univ. Math. J., 20, 1077–1092 (1971) Moser found the smallest value of K such that
$ \sup \left\{ {\int_\Omega {\exp \left( {\left( {\frac{{\left| {f(x)} \right|}} {K}} \right)^{{n \mathord{\left/ {\vphantom {n {(n - 1)}}} \right. \kern-\nulldelimiterspace} {(n - 1)}}} } \right):f \in W_0^{1,n} (\Omega ),\left\| {\nabla f} \right\|_{L^n } \leqslant 1} } \right\} < \infty $ \sup \left\{ {\int_\Omega {\exp \left( {\left( {\frac{{\left| {f(x)} \right|}} {K}} \right)^{{n \mathord{\left/ {\vphantom {n {(n - 1)}}} \right. \kern-\nulldelimiterspace} {(n - 1)}}} } \right):f \in W_0^{1,n} (\Omega ),\left\| {\nabla f} \right\|_{L^n } \leqslant 1} } \right\} < \infty   相似文献   

8.
We consider a new Sobolev type function space called the space with multiweighted derivatives $ W_{p,\bar \alpha }^n $ W_{p,\bar \alpha }^n , where $ \bar \alpha $ \bar \alpha = (α 0, α 1,…, α n ), α i ∈ ℝ, i = 0, 1,…, n, and $ \left\| f \right\|W_{p,\bar \alpha }^n = \left\| {D_{\bar \alpha }^n f} \right\|_p + \sum\limits_{i = 0}^{n - 1} {\left| {D_{\bar \alpha }^i f(1)} \right|} $ \left\| f \right\|W_{p,\bar \alpha }^n = \left\| {D_{\bar \alpha }^n f} \right\|_p + \sum\limits_{i = 0}^{n - 1} {\left| {D_{\bar \alpha }^i f(1)} \right|} ,
$ D_{\bar \alpha }^0 f(t) = t^{\alpha _0 } f(t),D_{\bar \alpha }^i f(t) = t^{\alpha _i } \frac{d} {{dt}}D_{\bar \alpha }^{i - 1} f(t),i = 1,2,...,n $ D_{\bar \alpha }^0 f(t) = t^{\alpha _0 } f(t),D_{\bar \alpha }^i f(t) = t^{\alpha _i } \frac{d} {{dt}}D_{\bar \alpha }^{i - 1} f(t),i = 1,2,...,n   相似文献   

9.
In this paper we consider the bifurcation problem -div A(x, u)=λa(x)|u|^p-2u+f(x,u,λ) in Ω with p 〉 1.Under some proper assumptions on A(x,ξ),a(x) and f(x,u,λ),we show that the existence of an unbounded branch of positive solutions bifurcating Irom the principal eigenvalue of the problem --div A(x, u)=λa(x)|u|^p-2u.  相似文献   

10.
This paper is devoted to the study of the period function for a class of reversible quadratic system
$ \begin{gathered} \dot x = - 2xy, \hfill \\ \dot y = k - 1 - 2kx + \left( {k + 1} \right)x^2 - \tfrac{1} {2}y^2 . \hfill \\ \end{gathered} $ \begin{gathered} \dot x = - 2xy, \hfill \\ \dot y = k - 1 - 2kx + \left( {k + 1} \right)x^2 - \tfrac{1} {2}y^2 . \hfill \\ \end{gathered}   相似文献   

11.
For the numerical evaluation of Cauchy principal value integrals of the form f(x)(x - λ) -1dx withλ ∈ (-1,1)and f ∈ C1[-1,1], we investigate the quadrature formula Q(n+1)Spl1[·;λ] obtained by replacing the integrand function f by its piecewise linear interpolant at an equidistant set of nodes as proposed by Rabinoivitz (Math. Comp. , 51:741 - 747,1988). We give upper bounds for the Peano - type error constantsfor s∈ {1,2}. These are the best possible constants in inequalities of the typeFurthermore, we prove that our upper bounds are asymptotically sharp.  相似文献   

12.
Let U(λ, μ) denote the class of all normalized analytic functions f in the unit disk |z| < 1 satisfying the condition
$ \frac{{f(z)}} {z} \ne 0and\left| {f'(z)\left( {\frac{z} {{f(z)}}} \right)^{\mu + 1} - 1} \right| < \lambda ,\left| z \right| < 1. $ \frac{{f(z)}} {z} \ne 0and\left| {f'(z)\left( {\frac{z} {{f(z)}}} \right)^{\mu + 1} - 1} \right| < \lambda ,\left| z \right| < 1.   相似文献   

13.
We study the rough bilinear fractional integral
$ \tilde B_{\Omega ,\alpha } (f,g)(x) = \int_{\mathbb{R}^n } {f(x + y)g(x - y)\frac{{\Omega (x,y')}} {{\left| y \right|^{n - \alpha } }}dy} , $ \tilde B_{\Omega ,\alpha } (f,g)(x) = \int_{\mathbb{R}^n } {f(x + y)g(x - y)\frac{{\Omega (x,y')}} {{\left| y \right|^{n - \alpha } }}dy} ,   相似文献   

14.
Suppose that X is a complex Banach space with the norm ‖·‖ and n is a positive integer with dim Xn ⩾ 2. In this paper, we consider the generalized Roper-Suffridge extension operator $ \Phi _{n,\beta _2 ,\gamma _2 , \ldots ,\beta _{n + 1} ,\gamma _{n + 1} } (f) $ \Phi _{n,\beta _2 ,\gamma _2 , \ldots ,\beta _{n + 1} ,\gamma _{n + 1} } (f) on the domain $ \Omega _{p_1 ,p_2 , \ldots ,p_{n + 1} } $ \Omega _{p_1 ,p_2 , \ldots ,p_{n + 1} } defined by
$ \Phi _{n,\beta _2 ,\gamma _2 , \ldots ,\beta _{n + 1} ,\gamma _{n + 1} } (f)(x) = {*{20}c} {\sum\limits_{j = 1}^n {\left( {\frac{{f(x_1^* (x))}} {{x_1^* (x)}}} \right)} ^{\beta _j } (f'(x_1^* (x)))^{\gamma _j } x_1^* (x)x_j } \\ { + \left( {\frac{{f(x_1^* (x))}} {{x_1^* (x)}}} \right)^{\beta _{n + 1} } (f'(x_1^* (x)))^{\gamma _{n + 1} } \left( {x - \sum\limits_{j = 1}^n {x_1^* (x)x_j } } \right)} \\ $ \Phi _{n,\beta _2 ,\gamma _2 , \ldots ,\beta _{n + 1} ,\gamma _{n + 1} } (f)(x) = \begin{array}{*{20}c} {\sum\limits_{j = 1}^n {\left( {\frac{{f(x_1^* (x))}} {{x_1^* (x)}}} \right)} ^{\beta _j } (f'(x_1^* (x)))^{\gamma _j } x_1^* (x)x_j } \\ { + \left( {\frac{{f(x_1^* (x))}} {{x_1^* (x)}}} \right)^{\beta _{n + 1} } (f'(x_1^* (x)))^{\gamma _{n + 1} } \left( {x - \sum\limits_{j = 1}^n {x_1^* (x)x_j } } \right)} \\ \end{array}   相似文献   

15.
By using the Riccati transformation and mathematical analytic methods,some sufficient conditions are obtained for oscillation of the second-order quasilinear neutral delay difference equations Δ[r n |Δz n | α-1 Δ z n ] + q n f (x n-σ)=0,where z n=x n + p n x n τ and ∞ Σ n=0 1 /r n 1/α < ∞.  相似文献   

16.
The following nontrivial estimate is obtained for short exponential sums: $$Sc\left( {\alpha ,x,y} \right) = \sum\limits_{x - y < n \leqslant x} {e\left( {\alpha \left[ {n^c } \right]} \right) < < y\ln ^A x,}$$ where $y \geqslant x^{\tfrac{1} {2}} \ln ^A x,x^{1 - c} y^{ - 1} \ln ^A x \leqslant \left| \alpha \right| \leqslant 0.5$ , c > 2 and ∥c∥ ≥ δ, A is a fixed positive number, and $\delta = \delta \left( {x,c,A} \right) = \left( {2^{\left[ c \right] + 1} - 1} \right)\left( {A + 2.5} \right) \cdot \frac{{\ln \ln x}} {{\ln x}}$ .  相似文献   

17.
In this contribution we consider the asymptotic behavior of sequences of monic polynomials orthogonal with respect to a Sobolev-type inner product
$ \left\langle p,q\right\rangle _{S}=\int_{0}^{\infty }p(x)q(x)x^{\alpha }e^{-x}dx+Np^{\prime }(a)q^{\prime }(a),\alpha >-1 $ \left\langle p,q\right\rangle _{S}=\int_{0}^{\infty }p(x)q(x)x^{\alpha }e^{-x}dx+Np^{\prime }(a)q^{\prime }(a),\alpha >-1  相似文献   

18.
Huffman, Park and Skoug established several results involving Fourier-Feynman transform and convolution for functionals in a Banach algebra S on the classical Wiener space. Chang, Kim and Yoo extended these results to abstract Wiener space for a more generalized Fresnel class $ \mathcal{F}_{\mathcal{A}_1 ,\mathcal{A}_2 } $ \mathcal{F}_{\mathcal{A}_1 ,\mathcal{A}_2 } A1,A2 than the Fresnel class $ \mathcal{F} $ \mathcal{F} (B)which corresponds to the Banach algebra S. In this paper we study Fourier-Feynman transform, convolution and first variation of unbounded functionals on abstract Wiener space having the form
$ F\left( x \right) = G\left( x \right)\psi \left( {\left( {\vec e,x} \right)^ \sim } \right) $ F\left( x \right) = G\left( x \right)\psi \left( {\left( {\vec e,x} \right)^ \sim } \right)   相似文献   

19.
20.
Based on the coincidence degree theory of Mawhin, we get a new general existence result for the following higher-order multi-point boundary value problem at resonance
$\begin{gathered} x^{(n)} (t) = f(t,x(t),x'(t),...,x^{(n - 1)} (t)),t \in (0,1), \hfill \\ x(0) = \sum\limits_{i = 1}^m {a_i x(\xi _i ),x'(0) = ... = x^{(n - 2)} (0) = 0,x^{(n - 1)} (1) = } \sum\limits_{j = 1}^l {\beta _j x^{(n - 1)} (\eta _j )} , \hfill \\ \end{gathered} $\begin{gathered} x^{(n)} (t) = f(t,x(t),x'(t),...,x^{(n - 1)} (t)),t \in (0,1), \hfill \\ x(0) = \sum\limits_{i = 1}^m {a_i x(\xi _i ),x'(0) = ... = x^{(n - 2)} (0) = 0,x^{(n - 1)} (1) = } \sum\limits_{j = 1}^l {\beta _j x^{(n - 1)} (\eta _j )} , \hfill \\ \end{gathered}   相似文献   

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