DSpace Collection: Volume 35, Number 2
http://hdl.handle.net/10525/2629
Serdica Mathematical Journal Volume 35, Number 2, 2009The Collection's search engineSearch the Channelsearch
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Multipliers on a Hilbert Space of Functions on R
http://hdl.handle.net/10525/2657
Title: Multipliers on a Hilbert Space of Functions on R<br/><br/>Authors: Petkova, Violeta<br/><br/>Abstract: For a Hilbert space H ⊂ L1loc(R) of functions on R we obtaina representation theorem for the multipliers M commuting with the shiftoperator S. This generalizes the classical result for multipliers in L2(R) aswell as our previous result for multipliers in weighted space L2ω(R). Moreover,we obtain a description of the spectrum of S.<br/><br/>Description: 2000 Mathematics Subject Classification: 42A45.Thu, 01 Jan 2009 00:00:00 GMTCourbure et Polygone de Newton
http://hdl.handle.net/10525/2656
Title: Courbure et Polygone de Newton<br/><br/>Authors: Hannachi M, M.; Mezaghcha, K.<br/><br/>Abstract: The object of this article relates to the study of the complex algebraic curves by using the concept of envelope convex. One proposes to characterize the points of a holomorphic complex curve (C) and to associate a metric invariant to them ( generalized curvature), by using the equations of the various segments constituting the polygon of Newton associated with (C).<br/><br/>Description: 2000 Mathematics Subject Classification: 26E35, 14H05, 14H20.Thu, 01 Jan 2009 00:00:00 GMTRelationship between Extremal and Sum Processes Generated by the same Point Process
http://hdl.handle.net/10525/2655
Title: Relationship between Extremal and Sum Processes Generated by the same Point Process<br/><br/>Authors: Pancheva, E.; Mitov, I.; Volkovich, Z.<br/><br/>Abstract: We discuss weak limit theorems for a uniformly negligible triangular array (u.n.t.a.) in Z = [0, ∞) × [0, ∞)^das well as for the associated with it sum and extremal processes on an open subset S . The complementof S turns out to be the explosion area of the limit Poisson point process. In order to prove our criterion for weak convergence of the sum processes we introduce and studysum processes over explosion area. Finally we generalize the model of u.n.t.a. to random sample size processes.<br/><br/>Description: 2000 Mathematics Subject Classification: Primary 60G51, secondary 60G70, 60F17.Thu, 01 Jan 2009 00:00:00 GMTDensity of Polynomials in the L^2 Space on the Real and the Imaginary Axes and in a Sobolev Space
http://hdl.handle.net/10525/2652
Title: Density of Polynomials in the L^2 Space on the Real and the Imaginary Axes and in a Sobolev Space<br/><br/>Authors: Klotz, Lutz; Zagorodnyuk, Sergey M.<br/><br/>Abstract: In this paper we consider an L^2 type space of scalar functions L^2 M, A (R u iR) which can be, in particular, the usual L^2 space of scalar functions on R u iR. We find conditions for density of polynomials in this space using a connection with the L^2 space of square-integrable matrix-valued functions on R with respect to a non-negative Hermitian matrix measure. The completness of L^2 M, A (R u iR ) is also established.<br/><br/>Description: 2000 Mathematics Subject Classification: 41A10, 30E10, 41A65.Thu, 01 Jan 2009 00:00:00 GMTBayesian Prediction of Weibull Distribution Based on Fixed and Random Sample Size
http://hdl.handle.net/10525/2651
Title: Bayesian Prediction of Weibull Distribution Based on Fixed and Random Sample Size<br/><br/>Authors: Ellah, A. H. Abd<br/><br/>Abstract: We consider the problem of predictive interval for future observations from Weibull distribution. We consider two cases they are: (i) fixed sample size (FSS), (ii) random sample size (RSS). Further, we derive the predictive function for both FSS and RSS in closed forms. Next, the upper and lower 1%, 2.5%, 5% and 10% critical points for the predictive functions are calculated. To show the usefulness of our results, we present some simulation examples. Finally, we apply our results to some real data set in life testing given in Lawless [16].<br/><br/>Description: 2000 Mathematics Subject Classification: 62E16, 65C05, 65C20.Thu, 01 Jan 2009 00:00:00 GMTOn Quasi-Normality of Two-Sided Multiplication
http://hdl.handle.net/10525/2648
Title: On Quasi-Normality of Two-Sided Multiplication<br/><br/>Authors: Amouch, M.<br/><br/>Abstract: In this note, we characterize quasi-normality of two-sided multiplication, restricted to a norm ideal and we extend this result, to an important class which contains all quasi-normal operators. Also we give some applications of this result.<br/><br/>Description: 2000 Mathematics Subject Classification: 47B47, 47B10, 47A30.Thu, 01 Jan 2009 00:00:00 GMT