An integral theorem and its applications to coincidence theorems
An isoperimetric inequality in R3
Another Perron type integration in dimensions as an extension of integration of stepfunctions
For a new Perron-type integral a concept of convergence is introduced such that the limit of a sequence of integrable functions , is integrable and any integrable is the limit of a sequence of stepfunctions , .
Approximate and Peano derivatives of nonintegral order
Let n be a nonnegative integer and let u ∈ (n,n+1]. We say that f is u-times Peano bounded in the approximate (resp. , 1 ≤ p ≤ ∞) sense at if there are numbers , |α| ≤ n, such that is in the approximate (resp. ) sense as h → 0. Suppose f is u-times Peano bounded in either the approximate or sense at each point of a bounded measurable set E. Then for every ε > 0 there is a perfect set Π ⊂ E and a smooth function g such that the Lebesgue measure of E∖Π is less than ε and f = g on Π....
Approximate maxima
Approximate of functions of two variables
Approximately generalized convex functions.
Approximation of Quasiconvex Functions, and Lower Semicontinuity of Multiple Integrals.
Approximations and error bounds for computing the inverse mapping
In this paper we propose a procedure to construct approximations of the inverse of a class of differentiable mappings. First of all we determine in terms of the data a neighbourhood where the inverse mapping is well defined. Then it is proved that the theoretical inverse can be expressed in terms of the solution of a differential equation depending on parameters. Finally, using one-step matrix methods we construct approximate inverse mappings of a prescribed accuracy.
Area functionals and Godbillon-Vey cocycles
We investigate the natural domain of definition of the Godbillon-Vey 2- dimensional cohomology class of the group of diffeomorphisms of the circle. We introduce the notion of area functionals on a space of functions on the circle, we give a sufficiently large space of functions with nontrivial area functional and we give a sufficiently large group of Lipschitz homeomorphisms of the circle where the Godbillon-Vey class is defined.
Associative -dimensional copulas
The associativity of -dimensional copulas in the sense of Post is studied. These copulas are shown to be just -ary extensions of associative 2-dimensional copulas with special constraints, thus they solve an open problem of R. Mesiar posed during the International Conference FSTA 2010 in Liptovský Ján, Slovakia.
Automatic differentiation platform : design
Automatic differentiation (AD) has proven its interest in many fields of applied mathematics, but it is still not widely used. Furthermore, existing numerical methods have been developed under the hypotheses that computing program derivatives is not affordable for real size problems. Exact derivatives have therefore been avoided, or replaced by approximations computed by divided differences. The hypotheses is no longer true due to the maturity of AD added to the quick evolution of machine capacity....
Automatic Differentiation Platform: Design
Automatic differentiation (AD) has proven its interest in many fields of applied mathematics, but it is still not widely used. Furthermore, existing numerical methods have been developed under the hypotheses that computing program derivatives is not affordable for real size problems. Exact derivatives have therefore been avoided, or replaced by approximations computed by divided differences. The hypotheses is no longer true due to the maturity of AD added to the quick evolution of machine capacity....
Baire category results for quasi–copulas
The aim of this manuscript is to determine the relative size of several functions (copulas, quasi– copulas) that are commonly used in stochastic modeling. It is shown that the class of all quasi–copulas that are (locally) associated to a doubly stochastic signed measure is a set of first category in the class of all quasi– copulas. Moreover, it is proved that copulas are nowhere dense in the class of quasi-copulas. The results are obtained via a checkerboard approximation of quasi–copulas.
Beiträge zur der Theorie der Umkehrung eines Functionensystems.
Bemerkung über gleichmässige Stetigkeit
Bemerkungen über die verschiedenen Werthe, welche eine Function zweier reellen Variabeln erhält, wenn man diese Variabeln entweder nacheinander oder gewissen Beziehungen gemäss gleichzeitig verschwinden lösst.
Bemerkungen zu Determinanten-Theorie. Auszug aus Briefen an Herrn Baltzer.
Bilipschitz mappings with derivatives of bounded variation .
Boundary Regularity for Minima of Certain Quadratic Functionals.