Publications
2009 |
Barranco, C. D.; Campaña, J. R.; Medina, J. M. Indexing Fuzzy numerical Data with a B+ Tree for Fast Retrieval Using Necessity-Measured Flexible conditions. Journal Article In: International Journal of Uncertainty, Fuzziness and Knowledge-Based Systems, vol. 17, pp. 1-23, 2009. Abstract | Links | BibTeX | Tags: Fuzzy data @article{Barranco2009,This paper proposes an indexing procedure for improving the performance of query processing on a fuzzy database. It focuses on the case when a necessity-measured atomic flexible condition is imposed on the values of a fuzzy numerical attribute. The proposal is to apply a classical indexing structure for numerical crisp data, a B+-tree combined with a Hilbert curve. The use of such a common indexing technique makes its incorporation into current systems straightforward. The efficiency of the proposal is compared with that of another indexing procedure for similar fuzzy data and flexible query types. Experimental results reveal that the performance of the proposed method is similar and more stable than that of its competitor. |
Barranco, C. D.; Helmer, S. Increasing the Performance of Fuzzy Retrieval Using Impact Ordering Conference IFSA / 6. EUSFLAT Conference 2009, 2009. Abstract | BibTeX | Tags: Fuzzy data @conference{Barranco2009b,We propose an approach for indexing fuzzy data based on inverted files that speeds up retrieval considerably by stopping the traversal of postings lists early. This is possible because the entries in the postings lists are organized in a way that guarantees that there are no matching items beyond a certain point in a list. Consequently, we can reduce the number of false positives significantly, leading to an increase in retrieval performance. We have implemented our ap- proach and evaluated it experimentally, comparing it to an approach that has previously been shown to be superior to other methods. Keywords— fuzzy databases, access methods, inverted files, physical design |
2008 |
Barranco, C. D.; Campaña, J. R.; Medina, J. M. A B+-tree based indexing technique for fuzzy numerical data Journal Article In: Fuzzy Sets and Systems, vol. 159, no. 12, pp. 1431-1449, 2008, ISSN: 0165-0114. Abstract | Links | BibTeX | Tags: Fuzzy data @article{Barranco2008,This paper proposes an indexing technique for fuzzy numerical data which increases the performance of query processing when the query involves an atomic possibility measured flexible condition. The proposal is based on a classical indexing mechanism for numerical crisp data, B-tree, which is implemented in most commercial database management systems (DBMS). This makes the proposed technique a good candidate for integration in a fuzzy DBMS when it is developed as an extension of a crisp DBMS. The efficiency of the proposal is contrasted with another indexing method for similar data and queries, G-tree, which is specifically designed to index multidimensional data. Results show that the proposal performance is similar to and more stable than the measured for G-tree when used for indexing fuzzy numbers. |
2007 |
Barranco, C. D.; Campaña, J. R.; Medina, J. M. An Indexing Technique for Fuzzy Numerical Data Conference Scalable Uncertainty Management, 2007, ISBN: 978-3-540-75410-7. Abstract | Links | BibTeX | Tags: Fuzzy data @conference{Barranco2007c,This paper introduces an indexing technique for fuzzy numerical data which relies on the classical, well-known and well-spread B+tree index data structure. The proposed indexing technique is specifically devised to increase the performance of query processing when a possibility measured flexible condition is involved. The proposal relies on the use of an indexing data structure implemented in virtually every database management system. This feature makes the proposal a good candidate to be used, with very low implementation effort, in a fuzzy database management system created as an extension of a classical one. The paper includes a performance analysis of the proposed indexing technique in contrast with other purpose equivalent techniques in order to evaluate the suitability of the proposal. |
2005 |
Barranco, C. D.; Campaña, J. R.; Medina, J. M. Towards a XML Fuzzy Structured Query Language Conference 4th EUSFLAT Conference 2005, 2005. Abstract | BibTeX | Tags: Fuzzy data @conference{Barranco2005,The paper introduces XFSQL (XML Fuzzy Struc- tured Query Language), a preliminary prototype of a portable query language for Fuzzy Database Management Systems (FDBMS) using the XML formatting rules. The need for a portable query language for FDBMSs is discussed, and a ba- sic language syntax and its associated datamodel are proposed. Additionally, the paper proposes a framework for implementing XFSQL query trans- lator interfaces, which would make a particu- lar FDBMS able to process XFSQL queries by translating them to the FDBMS proprietary fuzzy query language. Finally, an example of XFSQL query, together with its translation to the query language of a FDBMS implemented on a commer- cial DBMS, is shown. |
2004 |
Barranco, C. D.; Campaña, J. R.; Medina, J. M.; Pons, O. ImmoSoftWeb: a Web Based Fuzzy Application for Real Estate Management Conference Advances in Web Intelligence, 2004, ISBN: 978-3-540-24681-7. Abstract | Links | BibTeX | Tags: Fuzzy data @conference{Barranco2004,The paper describes ImmoSoftWeb, a web based application which takes advantage of fuzzy sets to apply them on the area of real estate management. ImmoSoftWeb is built on a FRDB, initially using a prototype called FSQL Server, which provides application capabilities for fuzzy handling, but ImmoSoftWeb is independent from FRDB by means of XML technologies usage. Moreover, the paper shows the way real estate attributes can be expressed using fuzzy data, and how fuzzy queries can be used to apply typical real estate customer requirements on a fuzzy real estate database. |