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941.
Semyon B. Yakubovich 《Journal of Approximation Theory》2004,131(2):175
We establish analogs of the Hausdorff–Young and Riesz–Kolmogorov inequalities and the norm estimates for the Kontorovich–Lebedev transformation and the corresponding convolution. These classical inequalities are related to the norms of the Fourier convolution and the Hilbert transform in Lp spaces, 1p∞. Boundedness properties of the Kontorovich–Lebedev transform and its convolution operator are investigated. In certain cases the least values of the norm constants are evaluated. Finally, it is conjectured that the norm of the Kontorovich–Lebedev operator is equal to . It confirms, for instance, by the known Plancherel-type theorem for this transform when p=2. 相似文献
942.
This is the second in a series of three papers; the other two are “Summation Formulas, from Poisson and Voronoi to the Present” [Progr. Math. 220 (2004) 419-440] and “Automorphic Distributions, L-functions, and Voronoi Summation for GL(3)” (preprint). The first paper is primarily expository, while the third proves a Voronoi-style summation formula for the coefficients of a cusp form on . The present paper contains the distributional machinery used in the third paper for rigorously deriving the summation formula, and also for the proof of the GL(3)×GL(1) converse theorem given in the third paper. The primary concept studied is a notion of the order of vanishing of a distribution along a closed submanifold. Applications are given to the analytic continuation of Riemann's zeta function, degree 1 and degree 2 L-functions, the converse theorem for GL(2), and a characterization of the classical Mellin transform/inversion relations on functions with specified singularities. 相似文献
943.
Kumi Yasuda 《Journal of Functional Analysis》2004,216(2):422-454
This article aims at showing a p-adic analogue of Selberg's trace formula, which describes a duality between the spectrum of a Hilbert-Schmidt operator and the length of prime geodesics appearing in the p-adic upper half-plane associated with a hyperbolic discontinuous subgroup of . Then we construct Markov processes on the fundamental domain relative to such subgroups, to whose transition operators the trace formula applied and a p-adic analogue of prime geodesic theorem is proved. 相似文献
944.
In this paper we define a new algebra generated by the difference operators D
q and D
q-1 with two analytic functions (x) and (x). Also, we define an operator M = J
1
J
2–J
3
J
4 s.t. all q-hypergeometric orthogonal polynomials Y
n(x), x cos(), are eigenfunctions of the operator M with eigenvalues
q
[n]
q
. The choice of (x) and (x) depend on the weight function of Y
n
(x). 相似文献
945.
Anatoliy Pinchuk 《Journal of Quantitative Spectroscopy & Radiative Transfer》2004,85(2):211-215
We calculated frequency-dependent real n(ω) and imaginary k(ω) parts of the complex refractive index for adenine A, guanine G, cytosine C and thymine T in ultraviolet range using Kramers-Kroning analysis of their absorption spectra. The frequency-dependent real ε′(ω) and imaginary ε″(ω) parts of the dielectric function for the corresponding nucleotides were restored. We calculated also the dependence of the dielectric function on the imaginary frequency ε(iω) for the corresponding nucleotides. 相似文献
946.
Birgitte Wuyts Dirk Bernard Nele Van Den Noortgate Johan Van De Walle Bruno Van Vlem Rita De Smet Frank De Geeter Raymond Vanholder Jean-Claude Libeer Joris Delanghe 《Accreditation and quality assurance》2004,10(1-2):15-19
When the calibration of a routine measurement procedure is traced back to metrological higher order, a significant discrepancy can occur between the analytical conditions of the routine measurement and the analytical conditions that were used in the clinical studies upon which the decision-making criteria are based. This can lead to serious interpretation errors with possible dramatic consequences for patients. The calibration of the creatinine Jaffé method is an excellent example of the importance of medical traceability. The compensated Jaffé method correlated accurately with the reference method and the compensated Jaffé creatinine clearance (CrCl), Cockroft and Gault and MDRD with the 51Cr EDTA clearance. The Schwartz estimate based upon the compensated Jaffé and enzymatic method overestimated, while uncompensated Jaffé slightly underestimated glomerular filtration rate (GFR). The situation in children is complex since serum creatinine concentrations are much lower in infants, rendering tubular secretion relatively more important. Low-molecular weight proteins have been suggested to replace serum creatinine as a marker for GFR. -trace protein, cystatin C, and 2-microglobulin showed good correlation with GFR. However, care should be taken in patients presenting with some malignant tumors, since significant increases of cystatin C in patients with metastatic melanoma or colorectal cancer has been reported.Presented at the 9th Conference on Quality in the Spotlight, 18-19 March 2004, Antwerp, Belgium 相似文献
947.
单分子电子器件的电子传输特性是当前分子电子学领域研究的热点.本文采用第一原理的ab inito法与格林函数方法,对Au电极-碳原子线-Au电极体系的电子结构以及电子传输等特性进行了分析,给出了C5、C10与C15原子线的电导 -电压曲线与伏安曲线.研究结果表明:碳原子线与Au电极之间的"接触"(结合)既有共价键的成分,又有离子键的成分;碳原子线的电导率及伏安特性具有特殊的量子效应和尺寸效应. 相似文献
948.
949.
Let A be an infinite subset of natural numbers, and X a positive real number. Let r(n) denotes the number of solution of the equation n=a1+a2 where a1?a2 and a1, a2∈A. Also let |A(X)| denotes the number of natural numbers which are less than or equal to X and belong to A. For those A which satisfy the condition that for all sufficiently large natural numbers n we have r(n)≠1, we improve the lower bound of |A(X)| given by Nicolas et. al. [NRS98]. The bound which we obtain is essentially best possible. 相似文献
950.
Qifan Zhang 《Journal of Number Theory》2004,105(1):192-202
We extend some classical results on polynomial functions . We prove all results in algebraic methods avoiding any combinatorial calculation. As applications of our methods, we obtain some interesting new results on permutation polynomials in several variables over some finite commutative rings. 相似文献