Kostas primary research focus lies in the realms of Databases, Geospatial Information Systems, and the Semantic Web.

PhD research on "LLM Spatial Reasoning and Optimizations in Geospatial RDF Stores"
Abstract: We study how optimizations in triple stores and geospatial knowledge graphs impact large language model performance in tasks such as augmented retrieval and question answering. Our approach leverages techniques including LLM-driven knowledge graph summarization, view materialization, and the construction of “cleaner”, more efficient geospatial knowledge graphs.