{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,7]],"date-time":"2026-02-07T19:48:49Z","timestamp":1770493729851,"version":"3.49.0"},"reference-count":35,"publisher":"Emerald","issue":"3","license":[{"start":{"date-parts":[[2023,9,25]],"date-time":"2023-09-25T00:00:00Z","timestamp":1695600000000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/www.emerald.com\/insight\/site-policies"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["EL"],"published-print":{"date-parts":[[2024,6,27]]},"abstract":"<jats:sec>\n<jats:title content-type=\"abstract-subheading\">Purpose<\/jats:title>\n<jats:p>There is an increasing interest in the use of knowledge graphs to represent real-world knowledge and a common need to manage imprecise knowledge in many real-world applications. This paper aims to study approaches to solve flexible queries over knowledge graphs.<\/jats:p>\n<\/jats:sec>\n<jats:sec>\n<jats:title content-type=\"abstract-subheading\">Design\/methodology\/approach<\/jats:title>\n<jats:p>By introducing fuzzy logic in the query answering process, the authors are able to obtain a novel algorithm to solve flexible queries over knowledge graphs. This approach is implemented in the FUzzy Knowledge Graphs system, a software tool with an intuitive user-graphical interface.<\/jats:p>\n<\/jats:sec>\n<jats:sec>\n<jats:title content-type=\"abstract-subheading\">Findings<\/jats:title>\n<jats:p>This approach makes it possible to reuse semantic web standards (RDF, SPARQL and OWL 2) and builds a fuzzy layer on top of them. The application to a use case shows that the system can aggregate information in different ways by selecting different fusion operators and adapting to different user needs.<\/jats:p>\n<\/jats:sec>\n<jats:sec>\n<jats:title content-type=\"abstract-subheading\">Originality\/value<\/jats:title>\n<jats:p>This approach is more general than similar previous works in the literature and provides a specific way to represent the flexible restrictions (using fuzzy OWL 2 datatypes).<\/jats:p>\n<\/jats:sec>","DOI":"10.1108\/el-02-2023-0052","type":"journal-article","created":{"date-parts":[[2023,9,21]],"date-time":"2023-09-21T07:57:06Z","timestamp":1695283026000},"page":"368-392","source":"Crossref","is-referenced-by-count":3,"title":["FUKG: answering flexible queries over knowledge graphs"],"prefix":"10.1108","volume":"42","author":[{"given":"Jos\u00e9 F\u00e9lix","family":"Yag\u00fce","sequence":"first","affiliation":[]},{"given":"Ignacio","family":"Huitzil","sequence":"additional","affiliation":[]},{"given":"Carlos","family":"Bobed","sequence":"additional","affiliation":[]},{"given":"Fernando","family":"Bobillo","sequence":"additional","affiliation":[]}],"member":"140","published-online":{"date-parts":[[2023,9,25]]},"reference":[{"key":"key2024062511251029300_ref001","volume-title":"The Description Logic Handbook: Theory, Implementation, and Applications","year":"2003"},{"issue":"3","key":"key2024062511251029300_ref002","doi-asserted-by":"crossref","first-page":"1","DOI":"10.4018\/jswis.2009081901","article-title":"Linked data \u2013 the story so far","volume":"5","year":"2009","journal-title":"International Journal on Semantic Web and Information Systems"},{"issue":"5","key":"key2024062511251029300_ref003","doi-asserted-by":"crossref","first-page":"1193","DOI":"10.1109\/TFUZZ.2015.2505329","article-title":"The role of crisp elements in fuzzy ontologies: the case of fuzzy OWL 2 EL","volume":"24","year":"2016","journal-title":"IEEE Transactions on Fuzzy Systems"},{"issue":"4","key":"key2024062511251029300_ref004","doi-asserted-by":"crossref","first-page":"475","DOI":"10.1142\/S0218488512500249","article-title":"Joining G\u00f6del and Zadeh fuzzy logics in fuzzy description logics","volume":"20","year":"2012","journal-title":"International Journal of Uncertainty, Fuzziness and Knowledge-Based Systems"},{"key":"key2024062511251029300_ref005","first-page":"1105","article-title":"Fuzzy description logics","volume-title":"Handbook of Mathematical Fuzzy Logic Volume III, Vol. 58 of Studies in Logic, Mathematical Logic and Foundations","year":"2015"},{"issue":"7","key":"key2024062511251029300_ref006","doi-asserted-by":"crossref","first-page":"1073","DOI":"10.1016\/j.ijar.2011.05.003","article-title":"Fuzzy ontology representation using OWL 2","volume":"52","year":"2011","journal-title":"International Journal of Approximate Reasoning"},{"key":"key2024062511251029300_ref007","unstructured":"Brickley, D. and Guha, R.V. 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