A Brief Account on the Recent Advances in the Use of Quantum Mechanics for Information Retrieval -- Cold Start Problem: a Lightweight Approach -- Content-based Keywords Extraction and Automatic Advertisement Associations to Multimodal News Aggregations -- ImageHunter: a novel tool for Relevance Feedback in Content Based Image Retrieval -- Temporal Characterization of the Requests to Wikipedia -- Interaction Mining: the new frontier of Customer Interaction Analytics -- A Linguistic Approach to Opinion Mining -- Sentiment Analysis in the Planet Art: a Case Study in the Social SemanticWeb -- OntoTimeFL - A Formalism for Temporal Annotation and Reasoning for Natural Language Text -- Representing Non Classical Concepts in Formal Ontologies Prototypes and Exemplars -- From Logical Forms to SPARQL Query with GETARUNS -- A DHT-based Multi-Agent System for Semantic Information Sharing -- A Decisional Multi-Agent Framework for Automatic Supply Chain Arrangement.

This volume focuses on new challenges in distributed Information Filtering and Retrieval. It collects invited chapters and extended research contributions from the DART 2011 Workshop, held in Palermo (Italy), on September 2011, and co-located with the XII International Conference of the Italian Association on Artificial Intelligence. The main focus of DART was to discuss and compare suitable novel solutions based on intelligent techniques and applied to real-world applications. The chapters of this book present a comprehensive review of related works and state of the art. Authors, both practitioners and researchers, shared their results in several topics such as "Multi-Agent Systems", "Natural Language Processing", "Automatic Advertisement", "Customer Interaction Analytics", "Opinion Mining".