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General integration and extensions.II

Štefan Schwabik (2010)

Czechoslovak Mathematical Journal

This work is a continuation of the paper (Š. Schwabik: General integration and extensions I, Czechoslovak Math. J. 60 (2010), 961–981). Two new general extensions are introduced and studied in the class 𝔗 of general integrals. The new extensions lead to approximate description of the Kurzweil-Henstock integral based on the Lebesgue integral close to the results of S. Nakanishi presented in the paper (S. Nakanishi: A new definition of the Denjoy’s special integral by the method of successive approximation,...

Henstock-Kurzweil and McShane product integration; descriptive definitions

Antonín Slavík, Štefan Schwabik (2008)

Czechoslovak Mathematical Journal

The Henstock-Kurzweil and McShane product integrals generalize the notion of the Riemann product integral. We study properties of the corresponding indefinite integrals (i.e. product integrals considered as functions of the upper bound of integration). It is shown that the indefinite McShane product integral of a matrix-valued function A is absolutely continuous. As a consequence we obtain that the McShane product integral of A over [ a , b ] exists and is invertible if and only if A is Bochner integrable...

Integrals and Banach spaces for finite order distributions

Erik Talvila (2012)

Czechoslovak Mathematical Journal

Let c denote the real-valued functions continuous on the extended real line and vanishing at - . Let r denote the functions that are left continuous, have a right limit at each point and vanish at - . Define 𝒜 c n to be the space of tempered distributions that are the n th distributional derivative of a unique function in c . Similarly with 𝒜 r n from r . A type of integral is defined on distributions in 𝒜 c n and 𝒜 r n . The multipliers are iterated integrals of functions of bounded variation. For each n , the spaces...

Kurzweil-Henstock and Kurzweil-Henstock-Pettis integrability of strongly measurable functions

B. Bongiorno, Luisa Di Piazza, Kazimierz Musiał (2006)

Mathematica Bohemica

We study the integrability of Banach valued strongly measurable functions defined on [ 0 , 1 ] . In case of functions f given by n = 1 x n χ E n , where x n belong to a Banach space and the sets E n are Lebesgue measurable and pairwise disjoint subsets of [ 0 , 1 ] , there are well known characterizations for the Bochner and for the Pettis integrability of f (cf Musial (1991)). In this paper we give some conditions for the Kurzweil-Henstock and the Kurzweil-Henstock-Pettis integrability of such functions.

Kurzweil-Henstock type integral on zero-dimensional group and some of its applications

Valentin Skvortsov, Francesco Tulone (2008)

Czechoslovak Mathematical Journal

A Kurzweil-Henstock type integral on a zero-dimensional abelian group is used to recover by generalized Fourier formulas the coefficients of the series with respect to the characters of such groups, in the compact case, and to obtain an inversion formula for multiplicative integral transforms, in the locally compact case.

Linear Stieltjes integral equations in Banach spaces

Štefan Schwabik (1999)

Mathematica Bohemica

Fundamental results concerning Stieltjes integrals for functions with values in Banach spaces have been presented in [5]. The background of the theory is the Kurzweil approach to integration, based on Riemann type integral sums (see e.g. [3]). It is known that the Kurzweil theory leads to the (non-absolutely convergent) Perron-Stieltjes integral in the finite dimensional case. Here basic results concerning equations of the form x(t) = x(a) +at [A(s)]x(s) +f(t) - f(a) are presented on the basis of...

Linear Volterra-Stieltjes integral equations in the sense of the Kurzweil-Henstock integral

Márcia Federson, Ricardo Bianconi (2001)

Archivum Mathematicum

In 1990, Hönig proved that the linear Volterra integral equation x t - ( K ) a , t α t , s x s d s = f t , t a , b , where the functions are Banach space-valued and f is a Kurzweil integrable function defined on a compact interval a , b of the real line , admits one and only one solution in the space of the Kurzweil integrable functions with resolvent given by the Neumann series. In the present paper, we extend Hönig’s result to the linear Volterra-Stieltjes integral equation x t - ( K ) a , t α t , s x s d g s = f t , t a , b , in a real-valued context.

McShane equi-integrability and Vitali’s convergence theorem

Jaroslav Kurzweil, Štefan Schwabik (2004)

Mathematica Bohemica

The McShane integral of functions f I defined on an m -dimensional interval I is considered in the paper. This integral is known to be equivalent to the Lebesgue integral for which the Vitali convergence theorem holds. For McShane integrable sequences of functions a convergence theorem based on the concept of equi-integrability is proved and it is shown that this theorem is equivalent to the Vitali convergence theorem.

Nonabsolutely convergent series

Dana Fraňková (1991)

Mathematica Bohemica

Assume that for any t from an interval [ a , b ] a real number u ( t ) is given. Summarizing all these numbers u ( t ) is no problem in case of an absolutely convergent series t [ a , b ] u ( t ) . The paper gives a rule how to summarize a series of this type which is not absolutely convergent, using a theory of generalized Perron (or Kurzweil) integral.

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