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Characterizations of Kurzweil-Henstock-Pettis integrable functions

L. Di Piazza, K. Musiał (2006)

Studia Mathematica

We prove that several results of Talagrand proved for the Pettis integral also hold for the Kurzweil-Henstock-Pettis integral. In particular the Kurzweil-Henstock-Pettis integrability can be characterized by cores of the functions and by properties of suitable operators defined by integrands.

Compact operators and integral equations in the ℋ𝒦 space

Varayu Boonpogkrong (2022)

Czechoslovak Mathematical Journal

The space ℋ𝒦 of Henstock-Kurzweil integrable functions on [ a , b ] is the uncountable union of Fréchet spaces ℋ𝒦 ( X ) . In this paper, on each Fréchet space ℋ𝒦 ( X ) , an F -norm is defined for a continuous linear operator. Hence, many important results in functional analysis, like the Banach-Steinhaus theorem, the open mapping theorem and the closed graph theorem, hold for the ℋ𝒦 ( X ) space. It is known that every control-convergent sequence in the ℋ𝒦 space always belongs to a ℋ𝒦 ( X ) space for some X . We illustrate how to apply results...

Continuity in the Alexiewicz norm

Erik Talvila (2006)

Mathematica Bohemica

If f is a Henstock-Kurzweil integrable function on the real line, the Alexiewicz norm of f is f = sup I | I f | where the supremum is taken over all intervals I . Define the translation τ x by τ x f ( y ) = f ( y - x ) . Then τ x f - f tends to 0 as x tends to 0 , i.e., f is continuous in the Alexiewicz norm. For particular functions, τ x f - f can tend to 0 arbitrarily slowly. In general, τ x f - f osc f | x | as x 0 , where osc f is the oscillation of f . It is shown that if F is a primitive of f then τ x F - F f | x | . An example shows that the function y τ x F ( y ) - F ( y ) need not be in L 1 . However, if f L 1 then τ x F - F 1 f 1 | x | ....

Controlled convergence theorems for Henstock-Kurzweil-Pettis integral on m -dimensional compact intervals

Sokol B. Kaliaj, Agron D. Tato, Fatmir D. Gumeni (2012)

Czechoslovak Mathematical Journal

In this paper we use a generalized version of absolute continuity defined by J. Kurzweil, J. Jarník, Equiintegrability and controlled convergence of Perron-type integrable functions, Real Anal. Exch. 17 (1992), 110–139. By applying uniformly this generalized version of absolute continuity to the primitives of the Henstock-Kurzweil-Pettis integrable functions, we obtain controlled convergence theorems for the Henstock-Kurzweil-Pettis integral. First, we present a controlled convergence theorem for...

Convergence theorems for the Perron integral and Sklyarenko's condition

Štefan Schwabik (1992)

Commentationes Mathematicae Universitatis Carolinae

It is shown that a uniform version of Sklyarenko's integrability condition for Perron integrals together with pointwise convergence of a sequence of integrable functions are sufficient for a convergence theorem for Perron integrals.

Convergence theorems for the PU-integral

Giuseppa Riccobono (2000)

Mathematica Bohemica

We give a definition of uniform PU-integrability for a sequence of μ -measurable real functions defined on an abstract metric space and prove that it is not equivalent to the uniform μ -integrability.

Denjoy integral and Henstock-Kurzweil integral in vector lattices. II

Toshiharu Kawasaki (2009)

Czechoslovak Mathematical Journal

In a previous paper we defined a Denjoy integral for mappings from a vector lattice to a complete vector lattice. In this paper we define a Henstock-Kurzweil integral for mappings from a vector lattice to a complete vector lattice and consider the relation between these two integrals.

Differential inclusions and multivalued integrals

Kinga Cichoń, Mieczysław Cichoń, Bianca Satco (2013)

Discussiones Mathematicae, Differential Inclusions, Control and Optimization

In this paper we consider the nonlocal (nonstandard) Cauchy problem for differential inclusions in Banach spaces x'(t) ∈ F(t,x(t)), x(0)=g(x), t ∈ [0,T] = I. Investigation over some multivalued integrals allow us to prove the existence of solutions for considered problem. We concentrate on the problems for which the assumptions are expressed in terms of the weak topology in a Banach space. We recall and improve earlier papers of this type. The paper is complemented...

Equations containing locally Henstock-Kurzweil integrable functions

Seppo Heikkilä, Guoju Ye (2012)

Applications of Mathematics

A fixed point theorem in ordered spaces and a recently proved monotone convergence theorem are applied to derive existence and comparison results for solutions of a functional integral equation of Volterra type and a functional impulsive Cauchy problem in an ordered Banach space. A novel feature is that equations contain locally Henstock-Kurzweil integrable functions.

Estimates of the remainder in Taylor’s theorem using the Henstock-Kurzweil integral

Erik Talvila (2005)

Czechoslovak Mathematical Journal

When a real-valued function of one variable is approximated by its n th degree Taylor polynomial, the remainder is estimated using the Alexiewicz and Lebesgue p -norms in cases where f ( n ) or f ( n + 1 ) are Henstock-Kurzweil integrable. When the only assumption is that f ( n ) is Henstock-Kurzweil integrable then a modified form of the n th degree Taylor polynomial is used. When the only assumption is that f ( n ) C 0 then the remainder is estimated by applying the Alexiewicz norm to Schwartz distributions of order 1.

Gauge integrals and series

Charles W. Swartz (2004)

Mathematica Bohemica

This note contains a simple example which does clearly indicate the differences in the Henstock-Kurzweil, McShane and strong McShane integrals for Banach space valued functions.

General integration and extensions. I

Štefan Schwabik (2010)

Czechoslovak Mathematical Journal

A general concept of integral is presented in the form given by S. Saks in his famous book Theory of the Integral. A special subclass of integrals is introduced in such a way that the classical integrals (Newton, Riemann, Lebesgue, Perron, Kurzweil-Henstock...) belong to it. A general approach to extensions is presented. The Cauchy and Harnack extensions are introduced for general integrals. The general results give, as a specimen, the Kurzweil-Henstock integration in the form of the extension of...

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