Pesquisa de Doutorado da Veronica

Vídeo -> https://youtu.be/P3-nklyrDx4 Denny Vrandečić, Lydia Pintscher, and Markus Krötzsch. 2023. Wikidata: The Making Of. In Companion Proceedings of the ACM Web Conference 2023 (WWW '23 Companion). Association for Computing Machinery, New York, NY, USA, 615–624. https://doi.org/10.1145/3543873.3585579 1 INTRODUCTION (5) Verifability, not truth : Wikidata relies on external sources for confrmation; statements can come with references; conficting or debated standpoints may co-exist The data collected in most of these projects can also be considered knowledge graphs, i.e., structured data collections that encode meaningful information in terms of (typed, directed) connections between concepts . Nevertheless, the actual data sets are completely diferent, both in their vocabulary and their underlying data model. In comparison to other approaches, Wikidata has one of the richest graph formats, where each statement (edge in the graph) can have user-defned annotations (e.g., validity...

Vídeo -> https://drive.google.com/file/d/1eQpa_VY7EpvPMUdQyvYNjdUrJdLLWIsc/view   How to Agree to Disagree Managing Ontological Perspectives using Standpoint Logic Lógica que acomoda diferentes pontos de vista Segundo A ... Segundo B .... Como inferir se as visões de A e B forem conflitantes? Standpoint logic bears some similarities to context logic in the style proposed by McCarthy and Buvac [19], which has also been applied in a description logic setting [15]. This tradition treats contexts as “first-class citizens” of the logic, i.e., full-fledged formal objects over which one can express first-order properties. In contrast, standpoint logic is suitable when a formalisation of the contexts involved is unfeasible, or when the interest resides in the content of the standpoints rather than the context in which they occur.   15. Klarman, S., Guti ́errez-Basulto, V.: Description logics of context. Journal of Logic and Com- putation 26(3), 817–854 (2013)   19. McCarthy, ...

Angles, R., Aranda, C.B., Hogan, A., Rojas, C., Vrgoč, D. (2022). WDBench: A Wikidata Graph Query Benchmark . In: , et al. The Semantic Web – ISWC 2022. ISWC 2022. Lecture Notes in Computer Science, vol 13489. Springer, Cham. https://doi.org/10.1007/978-3-031-19433-7_41   Abstract We propose WDBench: a query benchmark for knowledge graphs based on Wikidata, featuring real-world queries extracted from the public query logs of the Wikidata SPARQL endpoint. ... WDBench thus focuses on three main query features that are common to SPARQL and graph databases: (i) basic graph patterns, (ii) optional graph patterns, (iii) path patterns, and (iv) navigational graph patterns. ... Using this benchmark, we present and compare performance results for evaluating queries using Blazegraph, Jena/Fuseki, Virtuoso and Neo4j.   [4 grupos de queries, CGP somente OPTIONAL]   1 Introduction   With may options available, it can be difficult to choose a suitable engine to support queries ...

Vídeo -> https://youtu.be/ryxusv0s604?t=968 Vocabulário, significado, URI não é string, é ponteiro para conceito Ontologias para Compartilhar conhecimento comum a um grupo Tripla como formato de representação: uniformidade, simplicidade, escalabilidade, compatibilidade estrutural e metáfora de grafo (não é de fato) ... KG são mais complexos WD - Dez anos 26 '' exemplo de contexto temporal para a relação de empregador do Tim Berners Lee X CERN no WD e como representar com triplas (reificação) Query como forma de representar a semântica das informações que estão no KG SPARQL pode implementar somente a semântica do RDFS e OWL QL pq não pode expressar o que for mais complexo que N Log Space N3 Logic, SWRL, RIF e Datalog são mais complexos Datalog: permite regras com lógica de predicados simples, consultas conjuntivas e implementar OWL RL e OWL EL mas não permite DL. Também não permite a criação de estruturas RDF mais complexas. Existential Rules - parece com Datalog, simples, ló...

Peter F. Patel-Schneider: Contextualization via Qualifiers. CKGSemStats@ISWC 2018 Sarven Capadisli, Franck Cotton, José M. Giménez-García, Armin Haller, Evangelos Kalampokis, Vinh Nguyen, Amit P. Sheth, Raphaël Troncy: Joint Proceedings of the International Workshops on Contextualized Knowledge Graphs , and Semantic Statistics co-located with 17th International Semantic Web Conference (ISWC 2018). CEUR Workshop Proceedings 2317, CEUR-WS.org 2018 Abstract.  A common method for contextualizing facts in knowledge graph formalisms is by adding property-value pairs, qualifiers, to the facts in the knowledge graph.  [Afirmações contextualizadas e não fatos] Qualifiers work well for information that is additional to the base fact but pose an unwarranted burden on consumers of the information in knowledge graphs when the qualifier instead contextualizes the base fact, as in limiting the applicability of the fact to some time period or providing a confidence level for the fact.  [...