0000000000113605
AUTHOR
Edward Bryniarski
FORMAL CONCEPTION OF ROUGH SETS
In the paper we present a formal description of rough sets within the framework of the generalized set theory, which is interpreted in the set approximation theory. The rough sets are interpreted as approximations, which are defined by means of the Pawlak's rough sets.
Generalized Rough Sets in Contextual Spaces
This paper presents a generalization of Pawlak’s conception of rough sets [6] and [7]. It is more general than Pawlak’s solution of the problem of the definability of sets, the knowledge of which is incomplete and vague. The authors’ conception is based on conception of contextual space [4], which was inspired by Ziarko’s approach [12] to rough sets. Rough sets introduced by Pawlak [6] are particular cases of contextual rough sets defined in the contextual approximation space. This space is defined axiomatically by means of so called context relations. Every contextual rough set determined by set X can be determined by the union of the lower approximation of X and a subset of the boundary o…
Calculus of Contextual Rough Sets in Contextual Spaces
ABSTRACT The palier explains the methods of approximation of set which were earlier put forth by the authors (1995a, 1995b) and by W. Marek and H. Rasiowa (1986). An essential part of this paper is devoted to the presentation of a certain calculus of rough sets and contextual rough sets in contextual spaces.
Formal Description of Rough Sets
In the paper we present a formal description of rough sets within the limits of the generalized set theory, which is interpreted in the approximation of set theory. The rough sets are interpreted as an approximations, which are defined by means of the Pawlak’s rough sets.
Rough Search of Vague Knowledge
This chapter presents the theoretical basis of the vague knowledge search algorithmization of a rough method. It introduces some data granulation method which aggregates this data as rough sets of data or ways to search this data in the semantic networks. As a result of this method is the possibility of the rough sets description, analogically to sets in the classical theory of sets. We try to answer the question how the agent searching some knowledge can conceive the search of vague knowledge in the semantic networks: (1) if it can, accordingly to the semantic and the conceiving rules, describe the relationships between nodes in this semantic network which are identified as ways of searchi…
Rough Pragmatic Description Logic
In this chapter, a rough description logic is built on the basis of a pragmatic standpoint of representation of knowledge. The pragmatic standpoint has influenced the acceptance of a broader definition of the semantic network than that appearing in the literature. The definition of the semantic network is a motivation of the introduced semantics of the language of the descriptive logic. First, the theoretical framework of representation of knowledge that was proposed in the papers [24,25] is adjusted to the description of data processing. The pragmatic system of knowledge representation is determined, as well as situations of semantic adequacy and semantic inadequacy for represented knowled…
Extensions and intentions in the rough set theory
Abstract The approach to rough set theory proposed in this paper is based on the mutual correspondence of the concepts of extension and intension. It is different from the well-known approaches in the literature in that the upper approximations and the lower approximations of ‘unknown’ sets are considered as certain families of ‘known’ sets. This approach makes it possible to formulate necessary and sufficient conditions for the existence of operations on rough sets, which are analogous to classical operations on sets. The basic results presented in this paper, based on certain ideas of the second author, were formulated by the first author in his doctoral dissertation prepared under the su…