This book constitutes the proceedings of the 22nd International Semantic Web Conference, ISWC 2023, which took place in October 2023 in Athens, Greece. The 58 full papers presented in this double volume were thoroughly reviewed and selected from 248 submissions. Many submissions focused on the use of reasoning and query answering, witha number addressing engineering, maintenance, and alignment tasks for ontologies. Likewise, there has been a healthy batch of submissions on search, query, integration, and the analysis of knowledge. Finally, following the growing interest in neuro-symbolic approaches, there has been a rise in the number of studies that focus on the use of Large Language Models and Deep Learning techniques such as Graph Neural Networks.

This book constitutes the proceedings of the 22nd International Semantic Web Conference, ISWC 2023, which took place in October 2023 in Athens, Greece. The 58 full papers presented in this double volume were thoroughly reviewed and selected from 248 submissions. Many submissions focused on the use of reasoning and query answering, witha number addressing engineering, maintenance, and alignment tasks for ontologies. Likewise, there has been a healthy batch of submissions on search, query, integration, and the analysis of knowledge. Finally, following the growing interest in neuro-symbolic approaches, there has been a rise in the number of studies that focus on the use of Large Language Models and Deep Learning techniques such as Graph Neural Networks.

Ontologies are formal knowledge representation methods that can provide means for a shared understanding of a given domain. To enable meaningful communication and interoperability between two or more information systems that utilize independently created ontologies, a bridge between them is necessary, often referred to as an ontology alignment. Formal Methods for Managing and Processing Ontology Alignments provides complete ontology alignment lifecycle, including modelling, methods, and maintenance processes. Summarizing the author's research from the past ten years, this book consolidates findings previously published in prestigious international journals and presented at leading conferences. Each chapter is designed to be self-contained, allowing readers to approach the material modularly. The text introduces basic mathematical concepts, and later chapters build upon these foundations, but each focuses on specific aspects of ontology alignment, making the content accessible and easy to follow. Key Features Includes formal definitions of ontologies and ontology alignment along with a set of methods for providing semantics of attributes and relations. Provides application of fuzzy logic in the task of ontology alignment. Contains methods of managing the evolution of ontologies and their alignments. Proposes novel methods of assessing the quality ontology alignment. Situated in the fields of knowledge representation and semantic technologies, this book is an invaluable resource for both academic researchers and practitioners, as well as students looking to deepen their understanding.