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1

Satisfiability versus Finite Satisfiability in Elementary Modal Logics

Michaliszyn J., Otop J., Witkowski P.

Fundamenta Informaticae

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2018

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Vol. 163, nr 2

165--188

EN

We study variants of the satisfiability problem of elementary modal logics, i.e., modal logic considered over first-order definable classes of frames. The standard semantics of modal logic allows infinite structures, but often practical applications require to restrict our attention to finite structures. A number of decidability and undecidability results for the elementary modal logics were proved separately for general satisfiability and finite satisfiability. In this paper we justify that the results for both kinds of the satisfiability problem must be shown separately – we prove that there is a universal first-order formula that defines an elementary modal logic with decidable general satisfiability problem, but undecidable finite satisfiability problem, and, the other way round, that there is a universal first-order formula that defines an elementary modal logic with decidable finite satisfiability problem, but undecidable general satisfiability problem.

2

On Modalities and Quantifiers

Fitting M.

Fundamenta Informaticae

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2017

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Vol. 156, nr 3/4

297--330

EN

In 1951 in his book An Essay in Modal Logic, Georg Henrik von Wright strongly called attention to the analogies between quantifiers and modal operators. In 1984 I published a paper in Synthese examining the analogy formally. Confession: the presentation in that paper was badly done, and there is a significant (though correctable) error. Its time to repair the damage, present the ideas in a better way, and continue the investigation further. There are natural sublogics of classical first-order logic that are direct analogs of standard, basic modal logics. The behavior of quantifiers can be given a possible world semantics, some analogous to normal models, some to regular models, and some to neighborhood models. The firstorder logics have axiom systems and generally also tableau systems, paralleling those of modal logics. Many have the interpolation property. This gives concrete substance to von Wright’s observations. But then, what is the crucial difference between modal operators and quantifiers? This turns out to be surprising in its simplicity, and leads to an interesting way of looking at the familiar Henkin style completeness proof for first-order logic.

3

Specialized Predictor for Reaction Systems with Context Properties

Barbuti R., Gori R., Levi F., Milazzo P.

Fundamenta Informaticae

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2016

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Vol. 147, nr 2/3

173--191

EN

Reaction systems are a qualitative formalism for modeling systems of biochemical reactions characterized by the non-permanency of the elements: molecules disappear if not produced by any enabled reaction. Reaction systems execute in an environment that provides new molecules at each step. Brijder, Ehrenfeucht and Rozemberg introduced the idea of predictors. A predictor of a molecule s, for a given n, is the set of molecules to be observed in the environment to determine whether s is produced or not at step n by the system. We introduced the notion of formula based predictor, that is a propositional logic formula that precisely characterizes environments that lead to the production of s after n steps. In this paper we revise the notion of formula based predictor by defining a specialized version that assumes the environment to provide molecules according to what expressed by a temporal logic formula. As an application, we use specialized formula based predictors to give theoretical grounds to previously obtained results on a model of gene regulation.

4

A Tractable Rule Language in the Modal and Description Logic that Combines CPDL with Regular Grammar Logic

Nguyen L. A.

Fundamenta Informaticae

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2016

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Vol. 143, nr 1/2

113--139

EN

Combining CPDL (Propositional Dynamic Logic with Converse) and regular grammar logic results in an expressive modal logic denoted by CPDLreg. This logic covers TEAMLOG, a logical formalism used to express properties of agents’ cooperation in terms of beliefs, goals and intentions. It can also be used as a description logic for expressing terminological knowledge, in which both regular role inclusion axioms and CPDL-like role constructors are allowed. In this paper, we develop an expressive and tractable rule language called Horn-CPDLreg. As a special property, this rule language allows the concept constructor “universal restriction” to appear on the left hand side of general concept inclusion axioms. We use a special semantics for Horn-CPDLreg that is based on pseudo-interpretations. It is called the constructive semantics and coincides with the traditional semantics when the concept constructor “universal restriction” is disallowed on the left hand side of concept inclusion axioms or when the language is used as an epistemic formalism and the accessibility relations are serial. We provide an algorithm with PTIME data complexity for checking whether a knowledge base in Horn-CPDLreg has a pseudo-model. This shows that the instance checking problem in Horn-CPDLreg with respect to the constructive semantics has PTIME data complexity.

5

Consistency-based Revision of Structured Belief Bases

Korpusik M., Łukaszewicz W., Madalińska-Bugaj E.

Fundamenta Informaticae

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2015

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Vol. 136, nr 4

381--404

EN

In this paper we extend a consistency-based approach (originally introduced by Delgrande and Schaub) to belief revision for structured belief bases. We explicitly distinguish between observations, i.e., facts that an epistemic agent observes or is being told, and rules representing general knowledge about the considered world. When new information becomes available respective sets are being altered in a different way to preserve parts of knowledge during the revision process. Such an approach allows us to deal with difficult and complex scenarios, involving defeasible information and derivation filtering, with common-sense results.

6

Scenariusze rozwoju długodystansowego transportu pasażerskiego w Unii Europejskiej w perspektywie do 2030 r.

Pawłowska B., Bąk M., Borkowski P.

Logistyka

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2014

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nr 4

3127--3143

PL

Zmiany w strukturze i wolumenie transportu w Unii Europejskiej uwarunkowane są zarówno potrzebami transportowymi społeczeństw, jak i możliwościami oraz ograniczeniami europejskiego systemu transportowego. Ocena teraźniejszych i projekcja przyszłych zachowań transportowych jest warunkiem tworzenia sprawnego i efektywnego systemu transportowego. W obecnych czasach powszechnie wiadomo, że poprawa integracji międzygałęziowej w transporcie ma zasadnicze znaczenie dla lepszego wykorzystania istniejącej infrastruktury transportowej i ogólnej poprawy jakości transportu, zwiększając tym samym możliwości w zakresie mobilności społeczeństwa oraz oddziaływania na wybory pasażerów. Użytkownicy transportu potrzebują systemu dającego im optymalne możliwości przemieszczania się lub przewożenia ładunków w relacji drzwi-drzwi. Celem niniejszego artykułu jest przedstawienie opracowanych w ramach projektu ORIGAMI (Optimal Regulation and Infrastructure for Ground, Air and Maritime Interfaces) scenariuszy długookresowych popytu na usługi transportowe w długodystansowych przewozach pasażerskich do 2030 r. oraz analiza zachowań użytkowników i możliwości systemu transportowego w realizacji potrzeb transportowych.

EN

Changes in the modal structure and volume of transport in the European Union are determined both by users needs and the possibilities and limitations of the transport system. Assessment of the present and projected future travel behaviour is a precondition for creating an effective and efficient transport system. Nowadays, everyone knows that improving the integration of intermodal transport is essential to make better use of existing transport infrastructure and general improvement of transport service quality, thereby increasing the opportunities for social mobility and the impact on passengers' choices. Transport users need a system that gives them the best opportunities to move or carry goods in the door-to-door relationship. This article aim is to present scenarios for future demand development in long-distance passenger transport by 2030 elaborated within ORIGAMI (Optimal Regulation and Infrastructure for Ground, Air and Maritime Interfaces) project and to analyse user behaviour and capabilities of the transport system in the satisfaction of the transport needs.

7

Transport safety integration issues in mobility and modality management

Michalski L., Żukowska J.

Logistyka

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2010

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nr 2

EN

It is assumed that just like in other spheres of life, safety of transport will also benefit from integration as a result of more effective prevention and rescue efforts. The need for an integrated approach to many aspects of transport safety legitimizes proposals to change the relevant functional and institutional structures in Poland. This problem was addressed in the research project "Integrated Transport Safety System" (acronym ZEUS). The modal structure of transport accidents clearly shows that accident reduction can be achieved by promoting safer means of transport that can be used for particular transport needs. Before this can be achieved, safety management and mobility management must be integrated at the national, regional and local level.

PL

Procesy integracyjne w bezpieczeństwie transportu, podobnie jak w innych dziedzinach, przyczyniają się do skuteczności działań profilaktycznych i ratowniczych. Potrzeba zintegrowanego podejścia do rozwiązywania różnych problemów bezpieczeństwa uprawnia do tworzenia koncepcji i wizji zmian struktur funkcjonalnych i organizacyjnych, odpowiedzialnych za bezpieczeństwo transportu w Polsce. Problem ten jest także przedmiotem projektu badawczego "Zintegrowany system bezpieczeństwa transportu" o nazwie ZEUS. Skuteczna promocja bezpiecznych środków transportu uwarunkowana jest jednak integracją zarządzania bezpieczeństwem i mobilnością na poziomie krajowym, regionalnym i lokalnym.

8

On some properties of grounding nonuniform sets of modal conjunctions

Katarzyniak R. P.

International Journal of Applied Mathematics and Computer Science

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2006

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Vol. 16, no 3

399-412

EN

A language grounding problem is considered for nonuniform sets of modal conjunctions consisting of conjunctions extended with more than one modal operator of knowledge, belief or possibility. The grounding is considered in the context of semiotic triangles built from language symbols, communicative cognitive agents and external objects. The communicative cognitive agents are assumed to be able to observe external worlds and store the results of observations in internal knowledge bases. It is assumed that the only meaning accessible to these agents and assigned to modal conjunctions can be extracted from these internal knowledge bases. Commonsense requirements are discussed for the phenomenon of grounding nonuniform sets of modal conjunctions and confronted with an original idea of epistemic satisfaction relation used to define proper conditions for language grounding. Theorems are formulated and proved to show that the communicative cognitive agents based on the proposed model of grounding fulfill some commonsense requirements given for processing sets of nonuniform modal conjunctions. The main result is that the communicative cognitive agents considered can be constructed in a way that makes them rational and intentional as regards the processing of modal conjunctions and from the human point of view.