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941.
1 Besicovitch Inner ProductIll this paper, we consider Dirichlet serie8where an, tL = 1, 2,' ', are complex nunlbers. They are Besicovitch almost periodic functionsWe see the 8ystenl {e.(t); e.(t) = e--it Iog 1l, 71 = l, 2,' .} fOrnis a1l orthollor11la1 systelll witl1respect to tI1e BesicovitcI1 iIl1ler productThell we call fOrm the gelleralized trigouolnetrical polynolIlialsAccording to tl1e idea developed il1 [l],[2], auy Dirichlet seriesis weakly convergent over K witll respect to … 相似文献
942.
K. C. Kiwiel 《Journal of Optimization Theory and Applications》1986,48(3):437-449
This paper presents a method for minimizing the sum of a possibly nonsmooth convex function and a continuously differentiable function. As in the convex case developed by the author, the algorithm is a descent method which generates successive search directions by solving quadratic programming subproblems. An inexact line search ensures global convergence of the method to stationary points. 相似文献
943.
Summary The influence of the type and position of CH3, NH2 and OH groups in the pyrimidine ring, the eluent composition and the surface chemistry of the stationary phase on the retention of pyrimidine bases in reversed-phase liquid chromatography was investigated. On the basis of the hypothesis about the additivity of the adsorption energy the contribution of various structural groups on retention has been established. 相似文献
944.
Alinur Büyükaksoy Ahmet Demir 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》2005,56(4):694-717
A rigorous solution is presented for the problem of diffraction of plane harmonic sound waves by a cavity formed by a terminated rigid cylindrical waveguide of finite length whose interior surface is lined by an acoustically absorbent material. The solution is obtained by a modification of the Wiener-Hopf technique and involve an infinite series of unknowns, which are determined from an infinite system of linear algebraic equations. Numerical solution of this system is obtained for various values of the parameters of the problem and their effects on the diffraction phenomenon are shown graphically.Received: December 12, 2001 相似文献
945.
The energy of the stationary axisymmetric Einstein-Maxwell dilation-axion (EMDA) black hole is studied in the context of the Hamiltonian formulation of the teleparallel equivalence of general relativity (TEGR). The energy expression for the finite and arbitrary space-like two spheres is exactly computed by means of the integral form of the constraint equations of the formalism naturally without any restriction on the metric parameters. We also show that our results give the same values obtained by other methods for some special cases. 相似文献
946.
Yves Van Ingelgem Els Tourwé Orlin Blajiev Rik Pintelon Annick Hubin 《Electroanalysis》2009,21(6):730-739
Electrochemical impedance spectroscopy (EIS) is a powerful technique to study electrochemical processes and to perform screening tasks. Recently an integrated measuring and modeling methodology for EIS based on a multisine excitation signal was developed. A key issue in this methodology is the data analysis, allowing us to rapidly quantify the reliability of the measured data. In this paper, a comparison is made between classical single‐sine and the proposed multisine measurements on the same system. The fitting of the impedance data obtained by single‐or multisine excitation and using different weighting factors is also discussed. In addition to the advantages reported in earlier work, it is concluded that, of all investigated frequencies, the odd random phase multisine excitation yields the highest quality data in the shortest measurement time. 相似文献
947.
948.
949.
Antónia Földes 《Periodica Mathematica Hungarica》2005,50(1-2):117-134
Summary Some topics of our twenty some years of joint work is discussed. Just to name a few; joint behavior of the maximum of the Wiener process and its location, global and local almost sure limit theorems, strong approximation of the planar local time difference, a general Strassen type theorem, maximal local time on subsets. 相似文献
950.
This paper considers numerical simulation of time‐dependent non‐linear partial differential equation resulting from a single non‐linear conservation law in h, p, k mathematical and computational framework in which k=(k1, k2) are the orders of the approximation spaces in space and time yielding global differentiability of orders (k1?1) and (k2?1) in space and time (hence k‐version of finite element method) using space–time marching process. Time‐dependent viscous Burgers equation is used as a specific model problem that has physical mechanism for viscous dissipation and its theoretical solutions are analytic. The inviscid form, on the other hand, assumes zero viscosity and as a consequence its solutions are non‐analytic as well as non‐unique (Russ. Math. Surv. 1962; 17 (3):145–146; Russ. Math. Surv. 1960; 15 (6):53–111). In references (Russ. Math. Surv. 1962; 17 (3):145–146; Russ. Math. Surv. 1960; 15 (6):53–111) authors demonstrated that the solutions of inviscid Burgers equations can only be approached within a limiting process in which viscosity approaches zero. Many approaches based on artificial viscosity have been published to accomplish this including more recent work on H(Div) least‐squares approach (Commun. Pure Appl. Math. 1965; 18 :697–715) in which artificial viscosity is a function of spatial discretization, which diminishes with progressively refined discretizations. The thrust of the present work is to point out that: (1) viscous form of the Burgers equation already has the essential mechanism of viscosity (which is physical), (2) with progressively increasing Reynolds (Re) number (thereby progressively reduced viscosity) the solutions approach that of the inviscid form, (3) it is possible to compute numerical solutions for any Re number (finite) within hpk framework and space–time least‐squares processes, (4) the space–time residual functional converges monotonically and that it is possible to achieve the desired accuracy, (5) space–time, time marching processes utilizing a single space–time strip are computationally efficient. It is shown that viscous form of the Burgers equation without linearizing provides a physical and viablemechanism for approaching the solutions of inviscid form with progressively increasing Re. Numerical studies are presented and the computed solutions are compared with published work. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献