Similea, AlexandraAlexandraSimileaPetersen, NiklasNiklasPetersenLange, ChristophChristophLangeLohmann, SteffenSteffenLohmann2022-03-132022-03-132017https://publica.fraunhofer.de/handle/publica/39955410.1109/ICSC.2017.90The shortage of visual editors for RDF-based ontologies motivated us to develop a web client to visualize and edit ontologies represented as RDF graphs. Besides visual editing, we also wanted to support text-based editing to combine the "best of both worlds". Therefore, we realized the visual editor as an extension of the TurtleEditor, a text-based RDF editor supporting collaborative ontology engineering with features such as syntax highlighting, syntax checking, and auto-completion. Development challenges included synchronizing visual and text editing as well as clustering large RDF graphs. We evaluated the usability of the visual editing extension by conducting a user study and a performance test.en005006629conference paper