Fundamenta Informaticae - Volume 15, issue 2

Article Type: Other

DOI: 10.3233/FI-1991-15201

Citation: Fundamenta Informaticae, vol. 15, no. 2, pp. i-vi, 1991

Authors: Gao, Tiejun | Hosono, Chiharu | Yamanaka, Kenjirou

Article Type: Research Article

DOI: 10.3233/FI-1991-15202

Citation: Fundamenta Informaticae, vol. 15, no. 2, pp. 107-122, 1991

Authors: Biskup, Joachim | Convent, Bernhard

Article Type: Research Article

Abstract: In this paper the relationship between dependency theory and first-order logic is explored in order to show how relational chase procedures (i.e., algorithms to decide inference problems for dependencies) can be interpreted as clever implementations of well known refutation procedures of first-order logic with resolution and paramodulation. On the one hand this alternative interpretation provides a deeper insight into the theoretical foundations of chase procedures, whereas on the other hand it makes available an already well established theory with a great amount of known results and techniques to be used for further investigations of the inference problem for dependencies. Our …presentation is a detailed and careful elaboration of an idea formerly outlined by Grant and Jacobs which up to now seems to be disregarded by the database community although it definitely deserves more attention. Show more

DOI: 10.3233/FI-1991-15203

Citation: Fundamenta Informaticae, vol. 15, no. 2, pp. 123-138, 1991

Authors: Mycielski, Jan | Niwiński, Damian

Article Type: Research Article

DOI: 10.3233/FI-1991-15204

Citation: Fundamenta Informaticae, vol. 15, no. 2, pp. 139-144, 1991

Authors: Faber, V. | Mycielski, J.

Article Type: Research Article

DOI: 10.3233/FI-1991-15205

Citation: Fundamenta Informaticae, vol. 15, no. 2, pp. 145-167, 1991

Authors: Rauszer, Cecylia M.

Article Type: Research Article

Abstract: Stable autoepistemic sets are treated as S4 maximal theories. This approach allows to use the Lindenbaum algebra of modal logic as a tool in investigations of existence of a special kind of stable sets. Namely, for a given set A , the algebraic constructions of minimal stable sets based on A and moderately grounded expansions of A are shown.

DOI: 10.3233/FI-1991-15206

Citation: Fundamenta Informaticae, vol. 15, no. 2, pp. 168-179, 1991

Authors: Wiweger, Antoni

Article Type: Research Article

Abstract: Relations between general logical kits and kits of some particular type, called functional kits, are investigated. The functional representation R(K) of a logical kit K is constructed and it is shown that R(K) is a reflection of K in the category of kits and A-surjective kit homomorphisms with respect to the subcategory of functional kits.

Keywords: logical kit, knowledge representation system, functional kit, category, reflective subcategory

DOI: 10.3233/FI-1991-15207

Citation: Fundamenta Informaticae, vol. 15, no. 2, pp. 180-186, 1991

Authors: Skowron, Andrzej | Stepaniuk, Jaroslaw

Article Type: Research Article

Abstract: The purpose of this paper is to make the first step towards an approximation theory of discrete problems in which one can express and prove properties of approximating algorithms as well as carry out an approximate reasoning. We introduce an approximation propositional dynamic logic (APDL) with approximations of programs and formulas. We discuss the expressibility of APDL. The main theorem is the completeness theorem for a fragment of APDL. We consider also the approximation problem of properties expressible in APDL by a distinguished set of so called simple approximate formulas and programs, generated only from approximations of atomic properties and …approximations of atomic programs. The solution of the uniform approximation problem is presented and a result about an appoximation of decision algorithms is given. Show more

DOI: 10.3233/FI-1991-15208

Citation: Fundamenta Informaticae, vol. 15, no. 2, pp. 187-208, 1991