全文文献 工具书 数字 学术定义 翻译助手 学术趋势 更多

 共[5374]条 当前为第1条到20条[由于搜索限制，当前仅支持显示前5页数据]

 kernel The kernel of a certain derivation of the polynomial ringk[6] is shown to be nonfinitely generated overk (a field of charactersitic zero), thus giving a new counterexample to Hilbert's Fourteenth Problem. First we show that the representation ofG×G on eachG-biinvariant irreducible reproducing kernel Hilbert space in Hol(D) is a highest weight representation whose kernel is the character of a highest weight representation ofG. Using the scalar automorphy kernel ofD, we construct a ?*,G-invariant kernel onD×D×D. Taking a specific determination of its argument and studying its limit when approaching the Shilov boundary, we are able to define a ?-valued,G-invariant kernel for triples of mutually transversal points inS. Approximation of Distribution Spaces by Means of Kernel Operators We investigate conditions on kernel operators in order to provide prescribed orders of approximation in the Triebel-Lizorkin spaces. Our approach is based on the study of the boundedness of integral kernel operators and extends the Strang-Fix theory, related to the approximation orders of principal shift-invariant spaces, to a wide variety of spaces. We study the behavior of the ergodic singular integral τ associated to a nonsingular measurable flow {τ:t ∈ ?} on a finite measure space and a Calderón-Zygmund kernel with support in (0, ∞). The existence of the singular integral ∫K(x, y)f(y)dy associated to a Calderón-Zygmund kernel where the integral is understood in the principal value sense TF(x)=limε→0+∫|x-y|>amp;gt;εK(x, y)f(y)dy has been well studied. The first one is based on the use of the generalized Calderón reproducing formula and multidimensional fractional integrals with a Bessel function in the kernel. Specific kernel functions for the continuous wavelet transform in higher dimension and new continuous wavelet transforms are presented within the framework of Clifford analysis. Weighted Lp estimates (1>amp;lt;p>amp;lt;∞) are shown for oscillatory singular integral operators with polynomial phase and a rough kernel of the form eiP(x,y)Ω(x-y)h(|x-y|)|x-y|-n. We establish the characterization of the weighted Triebel-Lizorkin spaces for p=∞ by means of a "generalized" Littlewood-Paley function which is based on a kernel satisfying "minimal" moment and Tauberian conditions. We observe that our methods clearly show that the restriction p>amp;gt;2n/n+1 is closely related to cancellation and size properties of the gradient of the Poisson kernel. Assume that the associated Bochner-Riesz kernel sRδ satisfies the estimate, |sRδ(x, y)| ≤ C Rn/d(1+R1/d|x - y|-αδ+β)for some fixed constants a>amp;gt;0 and β. The proofs are based on sharp estimates of the derivatives of the Riesz kernel. As is well known the kernel of the orthogonal projector onto the polynomials of A pair of Clifford-Fourier transforms is defined in the framework of Clifford analysis, as operator exponentials with a Clifford algebra-valued kernel. Let $0 \neq f\in \mathcal{S}(\mathbb{R}^+).$ We show that Lf(L)δ, the distribution kernel of the operator Lf(L), is an admissible function on G. This method, which involves a kernel constructed from radial basis functions, has applications to problems in geophysics, and has the advantage of avoiding problems with poles.

 CNKI主页 |  设CNKI翻译助手为主页 | 收藏CNKI翻译助手 | 广告服务 | 英文学术搜索
2008 CNKI－中国知网

2008中国知网(cnki) 中国学术期刊(光盘版)电子杂志社