The representation of imprecise, uncertain or inconsistent information is not possible in relational databases, thus they require addonns to handle these types of information. One possible add-on is to allow the attributes to have values that are fuzzy sets on the attribute domain, which result in fuzzy relational databases (FRDB). From the implementational point of view, values are limited to ...

Flexible querying aims at expressing preferences inside queries instead of strict requirements. We consider ordinary relational databases and flexible querying calling on fuzzy sets. The topic of this paper is to define new types of flexible conditions : the ones involving the count operator. The main difficulty is to handle cardinalities of fuzzy sets. keywords : databases, flexible querying, ...

Although signi cant progress has been made in developing multidatabase systems that integrate component databases containing crisp data, little has been reported on integrating fuzzy databases in such systems. In this paper, we investigate the problem of integrating fuzzy relational databases in a multidatabase system. We identify new types of con icts that may occur in schemas and data due to ...

This paper presents a literature overview of Fuzzy Relational Database Models with emphasis on the role of functional dependencies in logical designing and modeling. The aim is the analysis of recent results in this fi eld. Fuzzy set theory is widely applied for the classical relational database extensions resulting in numerous contributions. This is because fuzzy sets and fuzzy logic are power...

Generating inferences from a gene regulatory network is important to understand the fundamental cellular processes, involving gene functions, and their relations. The availability of time-series gene expression data makes it possible to investigate the gene activities of the whole genomes. Under this framework, gene interaction is explained through a set of fuzzy relational matrices. By transfo...

In order to model the real world with imprecise and uncertain information, various extensions of the classical relational data model have been studied in literature using fuzzy set theory. However, vague set, as a generalized fuzzy set, has more powerful ability to process fuzzy information than fuzzy set. In this paper, we have proposed a vague relational database model and have defined a new ...

Assessing quality of distorted/decompressed images without reference to the original image is a challenging task because extracted features are often inexact and there exist complex relation between features and visual quality of images. The paper aims at assessing quality of distorted/decompressed images without any reference to the original image by developing a fuzzy relational classifier. H...

The purpose of this paper is to study the fuzzy fractional differentialequations. We prove that fuzzy fractional differential equation isequivalent to the fuzzy integral equation and then using this equivalenceexistence and uniqueness result is establish. Fuzzy derivative is considerin the Goetschel-Voxman sense and fractional derivative is consider in theRiemann Liouville sense. At the end, we...

The quotient operator plays an important role for query evaluation in relational databases. Its extension to fuzzy databases raises the question of the intended interpretation of the intermediary degrees attached to the items in the fuzzy relations. This note points out that the fuzzy quotient operator should be defined in slightly different ways depending on the possible interpretations of the...

In this paper, we introduce a special algebra called EQ-algebra which has three binary operations (meet, product, fuzzy equality) and a top element. The fuzzy equality is reflexive, symmetric and transitive with respect to the product. EQ-algebra is a natural algebra proposed as an algebra of truth values on the basis of which the fuzzy type theory (a higher-order fuzzy logic) should be develop...