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Logistyka
|
2015
|
nr 4
7793--7802, CD2
PL
W artykule przedstawiono elementy teorii semiotycznego podejścia do złożonych struktur obiektów i ich reaktorów z punktu widzenia zastosowań w procesach zarządzania kryzysowego reaktorami technologicznymi infrastruktury krytycznej państwa. Artykuł jest kontynuacją publikacji „Operacje na sieciach zdarzeń” przedstawionej w czasopiśmie „Logistyka” 5/2014. Przedmiotem rozważań są następujące grupy zagadnień: Hipergrafowe struktury obiektów, Hazard na kanałach obiektów, Sekwencje zdarzeń i poprawność procesów w cyklicznych i otwartych sieciach zdarzeń.
EN
The article presents the elements of the theory of semiotic approach to complex object structures and their reactors from the point of view of applications in disaster management processes in critical infrastructure of the state. The article is a continuation of the publication "Operations on network events" presented in the journal "Logistics" 5/2014. Question are the following issues: hypergraphs structure of objects, the phenomenon of hazard on the canals of objects, sequences of events and accuracy of processes in the cyclic and open networks of events.
2
Content available remote Towards a Formal Representation of Interactive Systems
EN
Powerful algebraic techniques have been developed for classical sequential computation. Many of them are based on regular expressions and the associated regular algebra. For parallel and interactive computation, extensions to handle 2-dimensional patterns are often required. Finite interactive systems, a 2-dimensional version of finite automata, may be used to recognize 2-dimensional languages. In this paper we present a blueprint for getting a formal representation of parallel, interactive programs and of their semantics. It is based on a recently introduced approach for getting regular expressions for 2-dimensional patterns, particularly using words of arbitrary shapes and powerful control mechanisms on composition. We extend the previously defined class of expressions n2RE with new control features, progressively increasing the expressive power of the formalism up to a level where a procedure for generating the words accepted by finite interactive systems may be obtained. Targeted applications come from the area of modelling, specification, analysis and verification of structured interactive programs via the associated scenario semantics.
3
Content available remote State Elimination Heuristics for Short Regular Expressions
EN
State elimination is an intuitive and easy-to-implement algorithm that computes a regular expression from a finite-state automaton (FA). It is very hard to compute the shortest regular expression for a given FA in general and we cannot avoid the exponential blow-up. This implies that state elimination cannot avoid the exponential blow-up either. Nevertheless, since the size of a regular expression by state elimination depends on the state removal sequence, we can have a shorter regular expression if we choose a better removal sequence for state elimination. This observation motivates us to examine state elimination heuristics based on the structural properties of the input FA and implement state elimination using the heuristics that run in polynomial time. We demonstrate the effectiveness of our algorithm by experiment results.
4
Content available remote Equivalence of Processes in Partially Commutative Object-Oriented Environments
EN
In this paper, the functional equivalence problem for processes, which is an important constituent of process optimization, is considered in object-oriented environments. Two basic cases are investigated: when the turn of operations execution is not essential for some objects while it is essential for the rest of them. In the first case, those objects are named commutative. Environments with both commutative and non-commutative objects are named partially commutative. It is shown, that the equivalence problem of processes in partially commutative environments that contain two or more commutative objects with more than one operation is unsolvable. The largest class of partially commutative environments is outlined where the equivalence problem is solvable (decidable). It is shown, that if there is only one object with two or more operations among commutative objects then the equivalence problem is solvable.
EN
The paper presents proposition of regular expressions engine based on the modified Thompson’s algorithm dedicated to the Polish language processing. The Polish inflectional dictionary has been used for enhancing regular expressions engine and syntax. Instead of using characters as a basic element of regular expressions patterns (as it takes place in BRE or ERE standards) presented tool gives possibility of using words from a natural language or labels describing words grammar properties in regex syntax.
PL
W artykule zaprezentowano propozycje mechanizmu wyrażeń regularnych w oparciu o zmodyfikowany algorytm Thompsona dostosowany do przetwarzania tekstów w języku polskim. Prezentowane wyrażenia regularne wykorzystują słownik fleksyjny języka polskiego i pozwalają na budowę wzorców, w których elementami podstawowymi są wyrazy języka polskiego lub etykiety gramatyczne, a nie znaki (jak to ma miejsce w klasycznych wyrażeniach regularnych standardu BRE czy ERE).
6
Content available remote Conversion of raster images into vector graphics
EN
This paper is focused on the conversion of raster images into vector graphics. File format conversion is a very well known problem in the area of computer graphics and there is a number of existing solutions, referenced in the literature. The article presents a novel solution of this particular problem, taking advantage of artificial intelligence, neural networks and fuzzy logic.
PL
Tematem artykułu jest przekształcanie rysunków rastrowych na rysunki wektorowe. Konwersja plików jest problemem znanym od dawna w grafice komputerowej i można znaleźć wiele rozwiązań w literaturze przedmiotu. W niniejszym artykule przedstawiono innowacyjne rozwiązanie tego problemu, wykorzystując algorytmy sztucznej inteligencji, sieci neuronowe i logikę rozmytą.
7
Content available remote Finite state automata built on DNA
EN
This paper describes a non-deterministic finite-state automaton based on DNA strands. The automaton uses massive parallel processing offered by molecular approach for computation and exhibits a number of advantages over traditional electronic implementations. This device is used to analyze DNA molecules, whether they are described by specified regular expression. Presented ideas are confirmed by experiment performed in a genetic engineering laboratory.
8
Content available remote Regular Expressions for Languages over Infinite Alphabets
EN
In this paper we introduce a notion of a regular expression over infinite alphabets and show that a language is definable by an infinite alphabet regular expression if and only if it is accepted by finite-state unification based automaton - a model of computation that is tightly related to other models of automata over infinite alphabets.
9
Content available remote On Finite Model Property of the Equational Theory of Kleene Algebras
EN
The finite model property of the equational fragment of the theory of Kleene algebras is a consequence of Kozen's [3] completeness theorem. We show that, conversely, this completeness theorem can be proved assuming the finite model property of this fragment.
10
Content available remote From Mirkin's prebases to Antimirov's world partial derivatives
EN
Our aim is to give a proof of the fact that two notions related to regular expressions, the prebases due to Mirkin and the partial derivatives introduced by Antimirov lead to the construction of identical nondeterministic automata recognizing the language of a given regular expression.
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