Fundamenta Informaticae - Volume 85, issue 1-4

Article Type: Research Article

Citation: Fundamenta Informaticae, vol. 85, no. 1-4, pp. i-i, 2008

Authors: Mirkowska, Grażyna | Salwicki, Andrzej | Swida, Oskar

Article Type: Research Article

Abstract: Our aim is to present a methodology that integrates all phases of software¡¯s production beginning from the specification phase, through the phase of programming and finally the phase of verification of program against its specification. The theoretical background of the methodology is algorithmic logic [8]. The environment for practical activities of this software project is a plugin SpecVer [11] extending the Eclipse development platform [2].

Citation: Fundamenta Informaticae, vol. 85, no. 1-4, pp. 1-17, 2008

Authors: Bednarczyk, Marek A. | Pawłowski, Wiesław | Bernardinello, Luca | Pomello, Lucia | Borzyszkowski, Tomasz

Article Type: Research Article

Abstract: We are concerned with the problem of defining a complex, hybrid, agent based discrete system in a modular way. Themodularity results from looking at the system from a number of different perspectives, each dealing with a specific aspect of the system. As a solution a synchronization operator is proposed which glues agent aware systems on shared agents and transitions. The construction turns out to be a categorical product. We also show that a logic to talk …about the temporal and the structural properties of the product can be obtained by gluing suitable logical frameworks from the components. Show more

Keywords: dynamic agents, synchronization, categorical semantics, models of concurrent, distributed and mobile computing, system specification

Citation: Fundamenta Informaticae, vol. 85, no. 1-4, pp. 19-33, 2008

Authors: Bellia, Marco | Occhiuto, M. Eugenia

Article Type: Research Article

Abstract: The paper investigates the use of preprocessing in adding higher order functionalities to Java, that is in passing methods to other methods. The approach is based on a mechanism which offers a restricted, disciplined, form of abstraction that is suitable to the integration of high order and object oriented programming. We show how this integration can be exploited in programming through the development of an example. Then, we discuss how the expressive power of the language …is improved. A new syntax is introduced for formal and actual parameters, hence the paper defines a translation that, at preprocessing time, maps programs of the extended language into programs of ordinary Java. Show more

Keywords: Higher order programming, object oriented programming, preprocessing

Citation: Fundamenta Informaticae, vol. 85, no. 1-4, pp. 35-50, 2008

Authors: Budzyńska, Katarzyna | Kacprzak, Magdalena

Article Type: Research Article

Abstract: In the article, we introduce a sound and complete deductive system (AGn) which can be used to reason about persuasion process performed in distributed systems of agents in circumstances of uncertain and incomplete information. In order to express degrees of beliefs of these agents, we adopt methods of Logic of Graded Modalities. To represent degrees' changes resulting from the persuasion, we apply tools of Algorithmic Logic and Dynamic Logic. As a result, we interpret arguments as …actions which lead to change of grades of agents' beliefs. Show more

Citation: Fundamenta Informaticae, vol. 85, no. 1-4, pp. 51-65, 2008

Authors: Chrz�stowski-Wachtel, Piotr | Findeisen, Paweł | Wolny, Grzegorz

Article Type: Research Article

Abstract: Workflows with transition execution times having exponential distributions are considered. The aim is to determine the overall execution time without looking into the reachability space and its analysis using Markov processes. We concentrate on the so called structural workflows, which are represented with Petri nets constructed by means of specific refinement rules. With each refinement rule (sequence, choice, parallelization, loop) we associate formulas which allow to compute the overall execution time distribution. …The class of exponential distributions is too narrow to keep the result within itself. We analyze the so called exponential polynomials, generalizing exponential distributions. They are closed under SUM and MAX functions. This closure property combined with the knowledge of refinements history enables us to find the requested formulas. Show more

Citation: Fundamenta Informaticae, vol. 85, no. 1-4, pp. 67-87, 2008

Authors: Czaja, Ludwik

Article Type: Research Article

Citation: Fundamenta Informaticae, vol. 85, no. 1-4, pp. 89-95, 2008

Authors: Delimata, Pawel | Suraj, Zbigniew

Article Type: Research Article

Abstract: Many problems in pattern classification and knowledge discovery require a selection of a subset of attributes or features to represent the patterns to be classified. The approach presented in this paper is designed mostly for multiple classifier systems with homogeneous (identical) classifiers. Such systems require many different subsets of the data set. The problem of finding the best subsets of a given feature set is of exponential complexity. The main aim of this paper is to …present ways to improve RBFS algorithm which is a feature selection algorithm. RBFS algorithm is computationally quite complex because it uses all decision-relative reducts of a given decision table. In order to increase its speed, we propose a new algorithm called ARS algorithm. The task of this algorithm is to decrease the number of the decision-relative reducts for a decision table. Experiments have shown that ARS has greatly improved the execution time of the RBFS algorithm. A small loss on the classification accuracy of the multiple classifier used on the subset created by this algorithm has also been observed. To improve classification accuracy the simplified version of the bagging algorithm has been applied. Algorithms have been tested on some benchmarks. Show more

Keywords: feature selection, multiple classifiers, reducts, diversity measures

Citation: Fundamenta Informaticae, vol. 85, no. 1-4, pp. 97-110, 2008

Authors: Farwer, Berndt | Jantzen, Matthias | Kudlek, Manfred | Rölke, Heiko | Zetzsche, Georg

Article Type: Research Article

Abstract: We present a generalization of finite automata using Petri nets as control, called Concurrent Finite Automata for short. Several modes of acceptance, defined by final markings of the Petri net, are introduced, and their equivalence is shown. The class of languages obtained by –free concurrent finite automata contains both the class of regular sets and the class of Petri net languages defined by final marking, and is contained in the class of context-sensitive languages.

Keywords: Finite automata, Petri nets

Citation: Fundamenta Informaticae, vol. 85, no. 1-4, pp. 111-121, 2008

Authors: Göhring, Daniel | Mellmann, Heinrich | Gerasymova, Kataryna | Burkhard, Hans-Dieter

Article Type: Research Article

Abstract: Common approaches for robot navigation use Bayesian filters like particle filters, Kalman filters and their extended forms. We present an alternative and supplementing approach using constraint techniques based on spatial constraints between object positions. This yields several advantages. The robot can choose from a variety of belief functions, and the computational complexity is decreased by efficient algorithms. The paper investigates constraint propagation techniques under the special requirements of navigation tasks. Sensor data …are noisy, but a lot of redundancies can be exploited to improve the quality of the result. We introduce two quality measures: The ambiguity measure for constraint sets defines the precision, while inconsistencies are measured by the inconsistency measure. The measures can be used for evaluating the available data and for computing best fitting hypothesis. A constraint propagation algorithm is presented. Show more

Keywords: Robot Navigation, Constraints

Citation: Fundamenta Informaticae, vol. 85, no. 1-4, pp. 123-137, 2008