Daniel Hernández
As a scientist, my goal is to address issues that have social significance or help us to preserve life on our planet. I'm also interested in databases, data on the Web, and incomplete information. My general research question is how people and communities can organize their knowledge and communicate on the Web. Why have proposals such as the Semantic Web and Linked Data not been adopted as one would have liked? This is not a simple problem. It involves technical and human issues. Worse, we don't have an agreement on what we would have liked. I believe that the Web of Data has to be universal, that is, it must not depend on a particular culture, software, hardware, or tech giant. Today, human communications are mainly controlled by a few tech giants, who have favored political manipulation, aggravated biases, and taken away from people the control of their data. Is the Semantic Web feasible? Would it contribute to a desired utopia or an unintended dystopia?
I am currently a postdoctoral researcher in the Analytic Computing department of the Institute for Artificial Intelligence at University of Stuttgart. Previously, I was a postdoctoral researcher in the Computer Science Department at Aalborg University and worked at Millennium Institute Foundational Research on Data in Chile. I hold a Ph.D. in Computer Science from the Department of Computer Science at the University of Chile. I'm interested in Open Data, databases, and the Web.
- Contact: daniel@degu.cl, danielh.hernandez@ki.uni-stuttgart.de.
- Research profiles: orcid, dblp, google.
- Other websites: dcc.uchile.cl.
- Social:
@daniel@mstdn.degu.cl
Publications
- Renzo Angles, Claudio Gutiérrez, and Daniel Hernández. Multiset Semantics in SPARQL, Relational Algebra and Datalog. Semantic Web -- Interoperability, Usability, Applicability, 2026.
- Diellza Elshani, Daniel Hernández, Ali Nakhaee, Victor Anthony Arrascue Ayala, Steffen Staab, and Thomas Wortmann. geof3D: SPARQL geometric functions for co-designing buildings. Advanced Engineering Informatics, 2026. (artifacts)
- Yuqicheng Zhu, Daniel Hernández, Yuan He, Zifeng Ding, Bo Xiong, Evgeny Kharlamov, and Steffen Staab. Predicate-Conditional Conformalized Answer Sets for Knowledge Graph Embeddings. Findings of the Association for Computational Linguistics, ACL 2025, Vienna, Austria, 2025-07. (arXiv)
- Ratan Bahadur Thapa, Daniel Hernández, Nico Brandt, Jan-Felix Klein, Etienne Hoffmann, Steffen Staab, Michael Selzer, and Gisela Lanza. A Roadmap to Create a Knowledge Graph for the Circular Factory for the Perpetual Product. Proceedings of The 3rd International Workshop on Knowledge Graphs for Sustainability (KG4S 2025) co-located with the 22nd Extended Semantic Web Conference (ESWC 2025), Portoroz, Slovenia, 2025.
- Diellza Elshani, Alessio Lombardi, Daniel Hernández, Steffen Staab, Al Fisher, and Thomas Wortmann. AEC Co-design workflow for cross-domain querying and reasoning using Semantic Web Technologies. Automation in construction, 2025.
- Nadeen Fathallah, Daniel Hernández, and Steffen Staab. AccessGuru: Leveraging LLMs to Detect and Correct Web Accessibility Violations in HTML Code. Proceedings of the 27th International ACM SIGACCESS Conference on Computers and Accessibility, ASSETS 2025, Denver, CO, USA, October 26-29, 2025, 2025. (artifacts) (arXiv)
- Yuqicheng Zhu, Nico Potyka, Daniel Hernández, Yuan He, Zifeng Ding, Bo Xiong, Dongzhuoran Zhou, Evgeny Kharlamov, and Steffen Staab. ArgRAG: Explainable Retrieval Augmented Generation using Quantitative Bipolar Argumentation. Proceedings of Machine Learning Research in 19th Conference on Neurosymbolic Learning and Reasoning, Santa Cruz, California, 2025. (arXiv)
- Yunjie He, Bo Xiong, Daniel Hernández, Yuqicheng Zhu, Evgeny Kharlamov, and Steffen Staab. DAGE : DAG Query Answering via Relational Combinator with Logical Constraints. WWW '25: The ACM Web Conference 2025, Sydney, Australia, 2025. (arXiv)
- Ali Elhalawati, Anastasia Dimou, Olaf Hartig, and Daniel Hernández. Flexible RML-Based Mapping of Property Graphs to RDF. Transforming Graph Data Workshop, Barcelona, Spain, 2025.
- Osama Mohammed, Jiaxin Pan, Mojtaba Nayyeri, Daniel Hernández, and Steffen Staab. Full-History Graphs with Edge-Type Decoupled Networks for Temporal Reasoning. ECAI 2025 - 28th European Conference on Artificial Intelligence, 25-30 October 2025, Bologna, Italy - Including 14th Conference on Prestigious Applications of Intelligent Systems (PAIS 2025), 2025. (arXiv)
- Cosimo Gregucci, Bo Xiong, Daniel Hernández, Lorenzo Loconte, Pasquale Minervini, Steffen Staab, and Antonio Vergari. Is Complex Query Answering Really Complex?. Forty-second International Conference on Machine Learning, ICML 2025, Vancouver, BC, Canada, July 13-19, 2025, 2025. (artifacts) (arXiv)
- Yuqicheng Zhu, Daniel Hernández, Yuan He, Zifeng Ding, Bo Xiong, Evgeny Kharlamov, and Steffen Staab. Predicate-Conditional Conformalized Answer Sets for Knowledge Graph Embeddings. Findings of the Association for Computational Linguistics, ACL 2025, Vienna, Austria, July 27 - August 1, 2025, 2025.
- Jiaxin Pan, Mojtaba Nayyeri, Osama Mohammed, Daniel Hernández, Rongchuan Zhang, Cheng Cheng, and Steffen Staab. Towards Foundation Model on Temporal Knowledge Graph Reasoning. , 2025.
- Diellza Elshani, Arlind Dervishaj, Daniel Hernández, Kjartan Gudmundsson, Steffen Staab, and Thomas Wortmann. An Ontology for the Reuse and Tracking of Prefabricated Building Components. Knowledge Graphs for Sustainability 2024, Hersonissos, Greece, May 27th, 2024, 2024-05. (artifacts)
- Zubaria Asma, Daniel Hernández, Luis Galárraga, Giorgos Flouris, Irini Fundulaki, and Katja Hose. NPCS: Native Provenance Computation for SPARQL. WWW '24, Singapore, 2024-05. (artifacts)
- Philipp Seifer, Daniel Hernández, Ralf Lämmel, and Steffen Staab. From Shapes to Shapes : Inferring SHACL Shapes for Results of SPARQL CONSTRUCT Queries. WWW '24 : The ACM Web Conference 2024, Singapore, 2024. (artifacts) (arXiv)
- Yunjie He, Daniel Hernández, Mojtaba Nayyeri, Bo Xiong, Yuqicheng Zhu, Evgeny Kharlamov, and Steffen Staab. Generating SROI\(^-\) Ontologies via Knowledge Graph Query Embedding Learning. ECAI 2024 - 27th European Conference on Artificial Intelligence, 19-24 October 2024, Santiago de Compostela, Spain - Including 13th Conference on Prestigious Applications of Intelligent Systems (PAIS 2024), 2024. (arXiv)
- Philipp Seifer, Daniel Hernández, Ralf Lämmel, and Steffen Staab. Inferring SHACL Constraints for Results of Composable Graph Queries (Extended Abstract). Proceedings of the 37th International Workshop on Description Logics (DL 2024), Bergen, Norway, June 18-21, 2024, 2024. (artifacts)
- Xinyi Pan, Daniel Hernández, Philipp Seifer, Ralf Lämmel, and Steffen Staab. eSPARQL : Representing and Reconciling Agnostic and Atheistic Beliefs in RDF-star Knowledge Graphs. 23rd International Semantic Web Conference, Baltimore, USA, 2024. (artifacts) (arXiv)
- Diellza Elshani, Daniel Hernández, Alessio Lombardi, Lasath Siriwardena, Tobias Schwinn, Al Fisher, Steffen Staab, Achim Menges, and Thomas Wortmann. Building Information Validation and Reasoning Using Semantic Web Technologies. CAAD Futures 2023, Delft, The Netherlands, 2023.
- Cosimo Gregucci, Mojtaba Nayyeri, Daniel Hernández, and Steffen Staab. Link Prediction with Attention Applied on Multiple Knowledge Graph Embedding Models. WWW '23 : The ACM Web Conference 2023, Austin, USA, 2023. (arXiv)
- Luis Galárraga, Daniel Hernández, Anas Katim, and Katja Hose. Visualizing How-Provenance Explanations for SPARQL Queries. ACM Web Conference 2023, WWW 2023, Austin, Texas, USA, 2023.
- Diellza Elshani, Alessio Lombardi, Al Fisher, Steffen Staab, Daniel Hernández, and Thomas Wortmann. Inferential Reasoning in Co-Design Using Semantic Web Standards alongside BHoM. 33. Forum Bauinformatik, München, 2022.
- Diellza Elshani, Alessio Lombardi, Al Fisher, Steffen Staab, Daniel Hernández, and Thomas Wortmann. Knowledge Graphs for Multidisciplinary Co-Design : Introducing RDF to BHoM. 10th Linked Data in Architecture and Construction Workshop (LDAC 2022), Hersonissos, Greece, 2022.
- Daniel Hernández, Luis Galárraga, and Katja Hose. Computing how-provenance for SPARQL queries via query rewriting. Proceedings of the VLDB Endowment, 2021. (experiment)
- Daniel Hernández, Claudio Gutiérrez, and Aidan Hogan. Certain Answers for SPARQL with Blank Nodes. The Semantic Web - ISWC 2018 - 17th International Semantic Web Conference, Monterey, CA, USA, October 8-12, 2018, Proceedings, Part I, 2018. (experiment)
- Daniel Hernández, Claudio Gutiérrez, and Renzo Angles. The problem of correlation and substitution in SPARQL-Extended Version. arXiv, 2018. (arXiv)
- Daniel Hernández and Claudio Gutiérrez. Semantics for Querying Paths in Graph Databases: No-repeated-node or No-repeated-edge?. Proceedings of the 11th Alberto Mendelzon International Workshop on Foundations of Data Management and the Web, Montevideo, Uruguay, June 7-9, 2017., 2017.
- Claudio Gutiérrez, Daniel Hernández, Aidan Hogan, and Axel Polleres. Certain Answers for SPARQL?. Proceedings of the 10th Alberto Mendelzon International Workshop on Foundations of Data Management, Panama City, Panama, May 8-10, 2016., 2016.
- Daniel Hernández, Aidan Hogan, Cristian Riveros, Carlos Rojas, and Enzo Zerega. Querying Wikidata: Comparing SPARQL, Relational and Graph Databases. The Semantic Web - ISWC 2016 - 15th International Semantic Web Conference, Kobe, Japan, October 17-21, 2016, Proceedings, Part II, 2016. (experiment)
- Daniel Hernández, Claudio Gutiérrez, and Renzo Angles. Correlation and Substitution in SPARQL. , 2016.
- Daniel Hernández and Claudio Gutiérrez. Disentangling the Notion of Dataset in SPARQL. Proceedings of the 9th Alberto Mendelzon International Workshop on Foundations of Data Management, Lima, Peru, May 6 - 8, 2015., 2015. (slides)
- Daniel Hernández, Aidan Hogan, and Markus Krötzsch. Reifying RDF: What Works Well With Wikidata?. Proceedings of the 11th International Workshop on Scalable Semantic Web Knowledge Base Systems co-located with 14th International Semantic Web Conference (ISWC 2015), Bethlehem, PA, USA, October 11, 2015., 2015. (experiment)