Interoperable Data Extraction and Analytics Queries over Blockchains -- Exploiting Twitter for Informativeness Classification in Disaster Situations -- COTILES: Leveraging Content and Structure for Evolutionary Community Detection -- A Weighted Feature-Based Image Quality Assessment Framework in Real-Time -- Sharing Knowledge in Digital Ecosystems Using Semantic Multimedia Big Data -- Facilitating and Managing Machine Learning and Data Analysis Tasks in Big Data Environments Using Web and Microservice Technologies -- Stable Marriage Matching for Homogenizing Load Distribution in a Cloud Data Center -- A Sentiment Analysis Software Framework for the Support of Business Information Architecture in the Tourist Sector.

The LNCS journal Transactions on Large-Scale Data- and Knowledge-Centered Systems focuses on data management, knowledge discovery, and knowledge processing, which are core and hot topics in computer science. Since the 1990s, the Internet has become the main driving force behind application development in all domains. An increase in the demand for resource sharing (e.g., computing resources, services, metadata, data sources) across different sites connected through networks has led to an evolution of data- and knowledge-management systems from centralized systems to decentralized systems enabling large-scale distributed applications providing high scalability. This, the 45th issue of Transactions on Large-Scale Data- and Knowledge-Centered Systems, contains eight revised selected regular papers. Topics covered include data analysis, information extraction, blockchains, and big data.