Rosseline Rodríguez

Automated System for Tests Preparation and Configuration Using Fuzzy Queries

In order to deal with user preferences and imperfect information in databases, a proposed solution is to apply fuzzy logic. It has given birth to fuzzy logic based extensions of SQL, such as SQLf. We present a real life application of fuzzy querying that fulfils an actual need of academic personal at a high studies institution. This application helps professors in tests preparation and configuration based on the reutilization of previously proposed questions. These questions are stored in a relational database keeping tracks of some interesting measures about difficult, answer time, correction time and so on. Queries as well as user preferences are specified using a graphic user interface. Thus professors must not directly deal with a query language and fuzzy logic concepts, but with an intuitive interface. The application is built on the SQLfi fuzzy querying engine that is a logic layer on top of existing relational DBMS.

Consultas con agrupamiento basado en similitud

The fuzzy sets allow for the representation of vague concepts, where membership of an object could be gradual. The use of this theory in the data bases has been proposed. As result of that, the fuzzy relational model GEFRED has emerged, as well as the fuzzy extended Entity-Relationship model FuzzyEER and the fuzzy querying language FSQL, among others. These extensions include some forms of fuzzy attributes, such as the so-called Type 3. These attributes have values in a set of labels provided with a fuzzy similarity relation, which is an extension of equivalence relations in the fuzzy set theory. The implications of such attributes in partitioned query operators have not been previously explored. The contribution of this paper is on the syntactic and semantic definition of an extension to SQL, in order to allow for partitioned queries with Type 3 fuzzy attributes in grouping criteria. This extension increases the expressive power of the database language with respect to previous proposals

Experiences on fuzzy DBMS: Implementation and use

This paper presents a comparison of three developmental experiences of fuzzy DBMS (Database Management Systems). These developments have expanded the functionality of some existing relational DBMS (PostgreSQL, Oracle, Firebird, SQL Server, MySQL and DB2) to handle queries with vague terms. The three approaches presented are based on three different methods of integration known as weak, medium and strong coupling strategies. These developments are based on evaluation mechanisms that give good behavior in terms of time spent for query processing. In addition, this paper also presents two user experiences of these fuzzy DBMS, which show a high acceptance by users. To do so, are some applications developed using our fuzzy DBMS. These experiences show that fuzzy DBMS are appropriate and necessary in real-world applications.

Framework for developing fuzzy applications

Traditionally, Database Management Systems (DBMS) allow queries whose evaluation is based on Boolean logic, i.e., verify whether or not a tuple in the query meets a given condition. However, these responses do not always meet the needs of a user, as he/she could prefer intermediate answers to their questions. Currently, there are DBMS that allow to specify fuzzy queries as well as to handle vague data over a database. On the other hand, framework use has grown because of the ease they provide towards the development of agile applications. This paper presents an extension of the Spring framework that allows connection to Fuzzy DBMS and is able to translate and evaluate fuzzy queries from fuzzy requirements. This extension can be incorporated into the work environment and be integrated in libraries for Java application development.