Fundamenta Informaticae - Volume 129, issue 1-2

Authors: Czaja, Ludwik

Article Type: Other

DOI: 10.3233/FI-2014-928

Citation: Fundamenta Informaticae, vol. 129, no. 1-2, pp. v-xii, 2014

Authors: Amin, Talha | Chikalov, Igor | Moshkov, Mikhail | Zielosko, Beata

Article Type: Research Article

Abstract: The paper describes a new tool for study relationships between length and coverage of exact decision rules. This tool is based on dynamic programming approach. We also present results of experiments with decision tables from UCI Machine Learning Repository.

Keywords: Decision rules, dynamic programming, length, coverage

DOI: 10.3233/FI-2014-956

Citation: Fundamenta Informaticae, vol. 129, no. 1-2, pp. 1-13, 2014

Authors: Chikalov, Igor | Hussain, Shahid | Moshkov, Mikhail

Article Type: Research Article

Abstract: This paper presents a new tool for the study of relationships between the total path length or the average depth and the number of misclassifications for decision trees. In addition to algorithm, the paper also presents the results of experiments with datasets from UCI ML Repository [9] and datasets representing Boolean functions with 10 variables.

Keywords: Decision trees, average depth, total path length, number of misclassifications

DOI: 10.3233/FI-2014-957

Citation: Fundamenta Informaticae, vol. 129, no. 1-2, pp. 15-26, 2014

Authors: Czaja, Ludwik

Article Type: Research Article

Abstract: Petri net structures are used as communication model of network systems where message transfer channels are represented by the nets' edges, communicating agents - by nets' places and actions of communication - by nets' transitions, which here are called transmissions. The role of (structured) tokens play send/receive statements, that arrive at random, which makes the distribution of edges change dynamically. In this sense a net is self-modyfying: although the set of agents-places is fixed, the channels and communicating actions vary in the course of the net activity. Problems of deadlock and fairness is investigated.

DOI: 10.3233/FI-2014-958

Citation: Fundamenta Informaticae, vol. 129, no. 1-2, pp. 27-36, 2014

Authors: Czyżewska, Marta | Szkoła, Jarosław | Pancerz, Krzysztof

Article Type: Research Article

Abstract: In the paper, we attempt to identify the crucial determinants of innovativeness economy and the correlations between the determinants. We based our research on the Innovativeness Union Scoreboard (IUS) dataset. In order to solve the problem, we propose to use the Double Self-Organizing Feature Map (SOM) approach. In the first step, countries, described by determinants of innovativeness economy, are clustered using SOMs according to five year time series for each determinant separately. In the second step, results of the first step are clustered again using SOM to obtain the final correlation represented in the form of a minimal spanning tree. …We propose some modifications of the clustering process using SOMs to improve classification results and efficiency of the learning process. Show more

DOI: 10.3233/FI-2014-959

Citation: Fundamenta Informaticae, vol. 129, no. 1-2, pp. 37-48, 2014

Authors: Herajy, Mostafa | Heiner, Monika

Article Type: Research Article

Abstract: Computational steering is an interactive remote control of a long running application. The user can adopt it, e.g., to adjust simulation parameters on the fly. Simulation of large-scale biochemical networks is often computationally expensive, particularly stochastic and hybrid simulation. Such extremely time-consuming computations necessitate an interactive mechanism to permit users to try different paths and ask “what-if-questions” while the simulation is in progress. Furthermore, with the progress of computational modelling and the simulation of biochemical networks, there is a need to manage multi-scale models, which may contain species or reactions at different scales. In this context, Petri nets are of …special importance, since they provide an intuitive visual representation of reaction networks. In this paper, we introduce a framework and its implementation for combining Petri nets and computational steering for the representation and interactive simulation of biochemical networks. The main merits of the developed framework are: intuitive representation of biochemical networks by means of Petri nets, distributed collaborative and interactive simulation, and tight coupling of simulation and visualisation. Show more

Keywords: Computational steering, Petri nets, Simulation of biochemical networks, Kinetic modelling software

DOI: 10.3233/FI-2014-960

Citation: Fundamenta Informaticae, vol. 129, no. 1-2, pp. 49-67, 2014

Authors: Jankowski, Andrzej | Skowron, Andrzej | Swiniarski, Roman W.

Article Type: Research Article

Abstract: We discuss an approach for dealing with uncertainty in complex systems. The approach is based on interactive computations over complex objects called here complex granules (c-granules, for short). Any c-granule consists of a physical part and a mental part linked in a special way. We begin from the rough set approach and next we move toward interactive computations on c-granules. From our considerations it follows that the fundamental issues of intelligent systems based on interactive computations are related to risk management in such systems. Our approach is a step toward realization of the Wisdom Technology (WisTech) program. The approach was …developed over years of work on different real-life projects. Show more

Keywords: interactions, granular computing, rough set, information granule, physical object, complex granule, interactive intelligent system, risk management

DOI: 10.3233/FI-2014-961

Citation: Fundamenta Informaticae, vol. 129, no. 1-2, pp. 69-84, 2014

Authors: Jard, Claude | Lime, Didier | Roux, Olivier H.

Article Type: Research Article

Abstract: Networks of Timed Automata (NTA) and Time Petri Nets (TPNs) are well-established formalisms used to model, analyze and control industrial real-time systems. The underlying theories are usually developed in different scientific communities and both formalisms have distinct strong points: for instance, conciseness for TPNs and a more flexible notion of urgency for NTA. The objective of the paper is to introduce a new model allowing the joint use of both TPNs and NTA for the modeling of timed systems. We call it Clock Transition System (CTS). This new model incorporates the advantages of the structure of Petri nets, while introducing …explicitly the concept of clocks. Transitions in the network can be guarded by an expression on the clocks and reset a subset of them as in timed automata. The urgency is introduced by a separate description of invariants. We show that CTS allow to express TPNs (even when unbounded) and NTA. For those two classical models, we identify subclasses of CTSs equivalent by isomorphism of their operational semantics and provide (syntactic) translations. The classical state-space computation developed for NTA and then adapted to TPNs can easily be defined for general CTSs. Armed with these merits, the CTS model seems a good candidate to serve as an intermediate theoretical and practical model to factor out the upcoming developments in the TPNs and the NTA scientific communities. Show more

Keywords: Real-time systems, Timed models, Timed Automata, Time Petri nets

DOI: 10.3233/FI-2014-962

Citation: Fundamenta Informaticae, vol. 129, no. 1-2, pp. 85-100, 2014

Authors: Köhler-Bußmeier, Michael

Article Type: Research Article

Abstract: In this paper we study the complexity of HORNETS, an algebraic extension of object nets. We define a restricted class: safe, elementary HORNETS, to guarantee finite state spaces. It will turn out, that the reachability problem for this class requires exponential space, which is a major increase when compared to safe, elementary object nets, which require polynomial space.

Keywords: Hornets, nets-within-nets, object nets, reachability, safeness

DOI: 10.3233/FI-2014-963

Citation: Fundamenta Informaticae, vol. 129, no. 1-2, pp. 101-115, 2014

Authors: Kudlek, Manfred | Flick, Nils Erik

Article Type: Research Article

Abstract: We present structural properties of languages constructed with catenation and shuffle, comprising iteration lemmata and closure properties of the language classes, as well as decidability results that follow.

DOI: 10.3233/FI-2014-964

Citation: Fundamenta Informaticae, vol. 129, no. 1-2, pp. 117-132, 2014

Authors: Kurbalija, Vladimir | Ivanović, Mirjana | von Bernstorff, Charlotte | Nachtwei, Jens | Burkhard, Hans-Dieter

Article Type: Research Article

Abstract: This paper outlines the primary steps to investigate if artificial agents can be considered as true substitutes of humans. Based on a Socially augmented microworld (SAM) human tracking behavior was analyzed using time series. SAM involves a team of navigators jointly steering a driving object along different virtual tracks containing obstacles and forks. Speed and deviances from track are logged, producing high-resolution time series of individual (training) and cooperative tracking behavior. In the current study 52 time series of individual tracking behavior on training tracks were clustered according to different similarity measures. Resulting clusters were used to predict cooperative tracking …behavior in fork situations. Results showed that prediction was well for tracking behavior shown at the first and, moderately well at the third fork of the cooperative track: navigators switched from their trained to a different tracking style and then back to their trained behavior. This matches with earlier identified navigator types, which were identified on visual examination. Our findings on navigator types will serve as a basis for the development of artificial agents, which can be compared later to behavior of human navigators. Show more

Keywords: Socially augmented microworld, time series analysis, artificial agents

DOI: 10.3233/FI-2014-965

Citation: Fundamenta Informaticae, vol. 129, no. 1-2, pp. 133-147, 2014

Authors: Polkowski, Lech | Semeniuk-Polkowska, Maria

Article Type: Research Article

Abstract: In this essay, we analyze various often semantically identified notions of separating things. In doing this, we contrast the set–theoretical approach based on the notion of an element/point with the mereological approach based on the notion of a part, hence, pointless. We address time aspect of the notion of a boundary and related notions as well as approximate notions defined in the realm of rough (approximate) mereology.

Keywords: spatial reasoning, boundary, mereology, mereotopology

DOI: 10.3233/FI-2014-966

Citation: Fundamenta Informaticae, vol. 129, no. 1-2, pp. 149-159, 2014

Authors: Szpyrka, Marcin | Matyasik, Piotr | Mrówka, Rafał | Kotulski, Leszek

Article Type: Research Article

Abstract: The paper presents a formal description of a subset of the Alvis language designed for the modelling and formal verification of concurrent systems. Alvis combines possibilities of a formal models verification with flexibility and simplicity of practical programming languages. Alvis provides a graphical modelling of interconnections among agents and a high level programming language used for the description of agents behaviour. Its semantic depends on the so-called system layer. The most universal system layer α0 , described in the paper, makes Alvis similar to other formal languages like Petri nets, process algebras, time automata, etc.

Keywords: Alvis modelling language, concurrent systems, formal methods

DOI: 10.3233/FI-2014-967

Citation: Fundamenta Informaticae, vol. 129, no. 1-2, pp. 161-176, 2014

Authors: Wiśniewski, Piotr | Stencel, Krzysztof

Article Type: Research Article

Abstract: Unified State Model (USM) is a single data model that allows conveying objects of major programming languages and databases. USM exploits and emphasizes common properties of their data models. USM is equipped with mappings from these data models onto it. With USM at hand, we have faced the next natural research question whether numerous query languages for the data subsumed by USM can be clearly mapped onto a common language. We have designed and proposed such a language called the Unified Query Language (UQL). UQL is intended to be a minimalistic and elegant query language that allows expressing queries of …languages of data models covered by USM. In this paper we define UQL and its concise set of operators. Next we conduct a mild introduction into UQL features by showing examples of SQL and ODMG OQL queries and their mapping onto UQL. We conclude by presenting the mapping of the theoretical foundations of these two major query languages onto UQL. They are the multiset relational algebra and the object query algebra. This is an important step towards the establishment of a fully-fledged common query language for USM and its subsumed data models. Show more

DOI: 10.3233/FI-2014-968

Citation: Fundamenta Informaticae, vol. 129, no. 1-2, pp. 177-192, 2014