Julien Plu defended his PhD thesis on knowledge extraction from web media. His research addressed three main challenges: 1) extracting entities from different types of texts and languages, 2) linking entities to multiple knowledge bases, and 3) adapting entity linking pipelines for different contexts. To extract entities, he evaluated various natural language processing techniques including phrase matching, sequence labeling using neural networks, and coreference resolution. He found that combining multiple named entity recognition models improved performance over using a single model. Plu's research provided methods for extracting and linking entities from diverse textual sources in an adaptable manner.