Kleene algebra axioms are complete with respect to both language models and binary relation models. In particular, two regular expressions recognise the same language if and only if they are universally equivalent in the model of binary relations. We consider Kleene allegories, i.e., Kleene algebras with two additional operations and a constant which are natural in binary relation models: inter...

The work presents a new method for the design of ideal secret sharing. The method uses regular mappings that are well suited for construction of perfect secret sharing. The restriction of regular mappings to permutations gives a convenient tool for investigation of the relation between permutations and ideal secret sharing generated by them.

A general formulation of the single machine scheduling problem with fuzzy parameters is proposed. Such notions as schedule, cost function and precedence relation are defined. The concept of f regular cost function is introduced and several properties of the class of problems with f -regular cost function are shown.

The local spectrum of a vertex set in a graph has been proven to be very useful to study some of its metric properties. It also has applications in the area of pseudo-distance-regularity around a set and can be used to obtain quasi-spectral characterizations of completely (pseudo-)regular codes. In this paper we study the relation between the local spectrum of a vertex set and the local spectru...

We consider random walks on idempotent semigroups, called Left Regular Bands, satisfying the relation xyx = xy for any two elements x and y of the semigroup. We give an alternating upper bound for the total variation distance of a random walk on a Left Regular Band semigroup, improving the previous bound by Brown and Diaconis.

We consider a relation between local and global characteristics of a differential algebraic variety. We prove that dimension of tangent space for every regular point of an irreducible differential algebraic variety coincides with dimension of the variety. Additionally, we classify tangent spaces at regular points in the case of one derivation.

This paper reports the characteristics of and mutual relationships between various combinatorial structures that give rise to certain imprimitive nonsymmetric three-class association schemes. Nontrivial relation graphs of an imprimitive symmetric 2-class association scheme are m ◦ Kr, (the union of m copies of the complete graph on r vertices) and its complement m ◦Kr, (the complete m-partite s...

This paper defines a notion of binding trees that provide a suitable model for second-order type systems with F-bounded quantifiers and equirecursive types. It defines a notion of regular binding trees that correspond in the right way to notions of regularity in the first-order case. It defines a notion of subtyping on these trees and proves various properties of the subtyping relation. It defi...

— In this paper it is shown that it is possible to transform any LL-regular grammar G into an LL{\) grammar G' in such a way that parsing G' is as good as parsing G. That ist a par se of a sentence of grammar G can be obtained with a simple string homomorphism from the parse of a corresponding sentence of G'. Since any LL (k) grammar is an LL-regular grammar the results which are obtained are v...

Protocol State Machines (PSM) in UML 2.0 [13] describe valid sequences of operation calls. To support modeling components, UML 2.0 introduces a Port associated with a set of provided and required interfaces. Unfortunately, a PSM is applicable only to a single interface, either a provided or required one; moreover, nested calls cannot be modeled with a PSM. Furthermore, the definition of protoco...