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Conceptual Information Compression and Efficient Pattern Search

Angelova, Galia, Mihov, Stoyan (2008)

Serdica Journal of Computing

This paper introduces an encoding of knowledge representation statements as regular languages and proposes a two-phase approach to processing of explicitly declared conceptual information. The idea is presented for the simple conceptual graphs where conceptual pattern search is implemented by the so called projection operation. Projection calculations are organised into off-line preprocessing and run-time computations. This enables fast run-time treatment of NP-complete problems, given that the intermediate...

Conditional problem for objective probability

Otakar Kříž (1998)

Kybernetika

Marginal problem (see [Kel]) consists in finding a joint distribution whose marginals are equal to the given less-dimensional distributions. Let’s generalize the problem so that there are given not only less-dimensional distributions but also conditional probabilities. It is necessary to distinguish between objective (Kolmogorov) probability and subjective (de Finetti) approach ([Col,Sco]). In the latter, the coherence problem incorporates both probabilities and conditional probabilities in a unified...

Contribution of František Matúš to the research on conditional independence

Milan Studený (2020)

Kybernetika

An overview is given of results achieved by F. Matúš on probabilistic conditional independence (CI). First, his axiomatic characterizations of stochastic functional dependence and unconditional independence are recalled. Then his elegant proof of discrete probabilistic representability of a matroid based on its linear representability over a finite field is recalled. It is explained that this result was a basis of his methodology for constructing a probabilistic representation of a given abstract...

Efficiency-conscious propositionalization for relational learning

Filip Železný (2004)

Kybernetika

Systems aiming at discovering interesting knowledge in data, now commonly called data mining systems, are typically employed in finding patterns in a single relational table. Most of mainstream data mining tools are not applicable in the more challenging task of finding knowledge in structured data represented by a multi-relational database. Although a family of methods known as inductive logic programming have been developed to tackle that challenge by immediate means, the idea of adapting structured...

Euler's Polyhedron Formula

Jesse Alama (2008)

Formalized Mathematics

Euler's polyhedron theorem states for a polyhedron p, thatV - E + F = 2,where V, E, and F are, respectively, the number of vertices, edges, and faces of p. The formula was first stated in print by Euler in 1758 [11]. The proof given here is based on Poincaré's linear algebraic proof, stated in [17] (with a corrected proof in [18]), as adapted by Imre Lakatos in the latter's Proofs and Refutations [15].As is well known, Euler's formula is not true for all polyhedra. The condition on polyhedra considered...

Evaluating many valued modus ponens

Dana Hliněná, Vladislav Biba (2012)

Kybernetika

This paper deals with many valued case of modus ponens. Cases with implicative and with clausal rules are studied. Many valued modus ponens via discrete connectives is studied with implicative rules as well as with clausal rules. Some properties of discrete modus ponens operator are given.

Experimental analysis of some computation rules in a simple parallel reasoning system for the ALC description logic

Adam Meissner (2011)

International Journal of Applied Mathematics and Computer Science

A computation rule determines the order of selecting premises during an inference process. In this paper we empirically analyse three particular computation rules in a tableau-based, parallel reasoning system for the ALC description logic, which is built in the relational programming model in the Oz language. The system is constructed in the lean deduction style, namely, it has the form of a small program containing only basic mechanisms, which assure soundness and completeness of reasoning. In...

Extraction of fuzzy logic rules from data by means of artificial neural networks

Martin Holeňa (2005)

Kybernetika

The extraction of logical rules from data has been, for nearly fifteen years, a key application of artificial neural networks in data mining. Although Boolean rules have been extracted in the majority of cases, also methods for the extraction of fuzzy logic rules have been studied increasingly often. In the paper, those methods are discussed within a five-dimensional classification scheme for neural-networks based rule extraction, and it is pointed out that all of them share the feature of being...

Flexible representation and querying of heterogeneous structured documents

Gloria Bordogna, Gabriella Pasi (2000)

Kybernetika

In this paper we present a fuzzy model for representing documents having a hierarchical structure and possibly containing multimedia information. We consider an archive containing documents with distinct (heterogeneous) logical structures. We also propose a flexible query language for expressing soft selection conditions on the structured documents. The documents’ content is organized into thematic (topical) sections where the index terms play a distinct role. The proposed document representation...

Formalisation des connaissances pour la simulation du service-retour en tennis : le système lift

Gil Denis, Alain Pizzinato (1993)

Mathématiques et Sciences Humaines

Dans cet article, nous présentons les aspects essentiels de la modélisation du processus décisionnel des joueurs de tennis dans une phase particulière de ce jeu sportif : le service-retour. Notre démarche se focalise sur la représentation des connaissances s'exerçant dans un continuum temporel scindé en micro-cycles et sur la construction de structures permettant d'envisager l'auto-apprentissage des caractéristiques technico-tactiques des joueurs par le système. Elle s'appuie sur la mise en oeuvre...

From computing with numbers to computing with words - From manipulation of measurements to manipulation of perceptions

Lotfi Zadeh (2002)

International Journal of Applied Mathematics and Computer Science

Computing, in its usual sense, is centered on manipulation of numbers and symbols. In contrast, computing with words, or CW for short, is a methodology in which the objects of computation are words and propositions drawn from a natural language, e.g., small, large, far, heavy, not very likely, the price of gas is low and declining, Berkeley is near San Francisco, it is very unlikely that there will be a significant increase in the price of oil in the near future, etc. Computing with words is inspired...

Fuzzy querying: issues and perspectives

Janusz Kacprzyk, Gabriella Pasi, Peter Vojtáš, Sławomir Zadrożny (2000)

Kybernetika

The term query is widely used in the database as well as information retrieval communities. Basically, a query against a collection of information items (to be called later, for brevity, an information source) provides a formal description of the items of interest to the user posing this query. A source of information is meant here very generally. It may take the form of an archive of multimedia or textual documents, a database, or a knowledge base. In the three previous examples the information...

Generalizations of the noisy-or model

Jiří Vomlel (2015)

Kybernetika

In this paper, we generalize the noisy-or model. The generalizations are three-fold. First, we allow parents to be multivalued ordinal variables. Second, parents can have both positive and negative influences on their common child. Third, we describe how the suggested generalization can be extended to multivalued child variables. The major advantage of our generalizations is that they require only one parameter per parent. We suggest a model learning method and report results of experiments on the...

Generalized Möbius transformation of knowledge bases

Milan Daniel (1998)

Kybernetika

Möbius transformation is an important tool for establishing weights of compositional expert systems rules from conditional weights. In this paper, an applicability of Möbius transformation of rule bases is also extended to knowledge bases with elementary disjunctions in antecedents of rules. This paper contains an existence theorem, an algorithm of the transformation and some open problems which tend to maximal generality as well.

Hierarchical text categorization using fuzzy relational thesaurus

Domonkos Tikk, Jae Dong Yang, Sun Lee Bang (2003)

Kybernetika

Text categorization is the classification to assign a text document to an appropriate category in a predefined set of categories. We present a new approach for the text categorization by means of Fuzzy Relational Thesaurus (FRT). FRT is a multilevel category system that stores and maintains adaptive local dictionary for each category. The goal of our approach is twofold; to develop a reliable text categorization method on a certain subject domain, and to expand the initial FRT by automatically added...

How to secure a high quality knowledge base in a rulebased system with uncertainty

Beata Jankowska (2006)

International Journal of Applied Mathematics and Computer Science

Although the first rule-based systems were created as early as thirty years ago, this methodology of expert systems designing still proves to be useful. It becomes especially important in medical applications, while treating evidence given in an electronic format. Constructing the knowledge base of a rule-based system and, especially, of a system with uncertainty is a difficult task because of the size of this base as well as its heterogeneous character. The base consists of facts, ordinary rules...

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