Artificial Intelligence and Knowledge Representation Laboratory

This page describes the Artificial Intelligence and Knowledge Representation Lab of the Dipartimento di Ingegneria Informatica Automatica e Gestionale Antonio Ruberti of Sapienza Università di Roma.

Research lines:

• Description Logics

• Logics for AI

• Semantic Technologies

• Reasoning about Actions & Planning

• Spoken Language Understanding


Professors: Maurizio Lenzerini (leader) Giuseppe De Giacomo, Domenico Lembo, Paolo Liberatore, Daniele Nardi, Fabio Patrizi, Antonella Poggi, Riccardo Rosati.

PhD Students: Federico Croce, Federico Maria Scafoglieri, Marina Morelli, Gianluca Cima.

Post Docs: Lorenzo Lepore, Marco Ruzzi, Valerio Santarelli, Domenico Fabio Savo.

Other Collaborators: Giacomo Ronconi.

Description of research topics:

Research in Artificial Intelligence at DIAG started in the early 80s and established this research group as one of the most prominent ones in the field of logic-based knowledge representation and automated reasoning. Research has been conducted in many areas, with several outstanding results. The research lines presently active are described in the following.

Description Logics (DL) form a family of Logic-based Knowledge Representation Languages which allow for modeling an application domain in terms of objects, concepts and relationships between concepts, and for reasoning about them. They are widely used in several areas, including ontology engineering, Semantic Web, and information integration. The research at DIAG on DL has a long tradition, and focuses on many relevant aspects, including algorithms for automated reasoning, trade-off between expressive power and computational complexity of reasoning, query answering in DL knowledge bases, adding both monotonic and non-monotonic rules to DL. In the future, the work on DL will both continue along the above mentioned lines and focus on dynamic aspects, such as update and revision of DL knowledge bases, and reasoning about programs expressed on such knowledge bases.

Semantic Technologies aim at intelligent information processing by creating and connecting machine-understandable information, sometimes called the Semantic Web. Our research in this area mainly focuses on representation languages, in particular for ontologies. A remarkable outcome of our research in this area is the standardization of the OWL 2 QL ontology specification language by the World Wide Web Consortium. OWL 2 QL directly derives from DL-Lite, a family of ontology formalisms which we proposed and studied in our recent research in this field.

Reasoning about Actions concerns the theory and the implementation of agents that reason, act and perceive in changing, incompletely known, and unpredictable environments. Such agents must have higher level cognitive functions that involve reasoning, for example, about goals, actions, when to perceive and what to look for, the cognitive states of other agents, time, collaborative task execution, etc. Our research on Reasoning about Actions focuses on several aspects, including: foundations of theory of actions; various forms of planning or automated process synthesis for sophisticated dynamic properties, e.g., expressed in mu-calculus, ATL, LTL, LTLf , and LDLf ; high-level agent programs, like ConGolog based on the Situation Calculus; agent behavior synthesis and composition.

This research is also related with, and applied to, other areas, such as cognitive robotics, multi-agent/multi-robot systems, software service modeling, execution and composition, high-level programs and business processes over ontologies and data sources. One specific application where knowledge representation has been applied is Spoken Language Understanding in the context of Robotics. Specifically, we have addressed the interpretation of spoken commands and the extension to handle more complex forms of dialog. The knowledge about the environment and the robot capabilities are used by the system in order to build the language that specifies robot commands. Moreover, the knowledge about the environment (semantic map), can be used to bias the interpretation of commands through a spoken language command interpretation chain that is based on statistical off-the-shelf tools.

Several group members are recipients of prestigious awards, are regularly involved in editorial activities of the scientific community, and are invited to deliver keynote talks at international conferences or workshops. Awards and honours include: AAAI Fellowships: Maurizio Lenzerini, since 2017; Giuseppe De Giacomo, since 2016; Luigia Carlucci Aiello, since 1995; EurAI Fellowships: Riccardo Rosati, since 2016, Giuseppe De Giacomo, since 2012, Daniele Nardi, since 2009, Maurizio Lenzerini, since 2008; Luigia Carlucci Aiello, since 1999; Membership to the European Academy of Sciences and Arts (Luigia Carlucci Aiello, since 2005); ACM Fellowships (Maurizio Lenzerini, since 2009; Giuseppe De Giacomo, since 2016); Membership to the Academia Europaea –The Academy of Europe (Maurizio Lenzerini, since 2011); IJCAI Distinguished Service Award (Luigia Carlucci Aiello, 2009); ECCAI Distinguished Services Award (Luigia Carlucci Aiello, 2014); Doctorate Honoris Causa (Luigia Carlucci Aiello, 2002, School of Technology, University of Linkoping, Sweden); ACM ¨ Recognition Service Award (Maurizio Lenzerini, 2011).

Several group members are involved in various prestigious editorial activities: Giuseppe De Giacomo is Review Editor of Artificial Intelligence (Elsevier) and member of the Editorial Board of Acta Informatica, he is Vice-President of the Steering Committee Member of the International Conference on Principles of Knowledge Representation and Reasoning (KR), he is Area Chair of the 27th International Joint Conference on Artificial Intelligence (IJCAI 2018) and of the 32nd AAAI Conference on Artificial Intelligence (AAAI 2018); Domenico Lembo is Steering Committee Member of the International Conference on Web Reasoning an Rule Systems (RR), since 2016, and Chair of the 13th Reasoning Web Summer School (RW 2017). Maurizio Lenzerini is Area Editor of Information Systems –An International Journal, for the area of Data Modeling and Knowledge Representation and Reasoning Techniques, Editorial Board member of Intelligenza Artificiale, The International Journal of the AI*IA, Area Editor of the Journal of Applied Logic for the area of Logic for Knowledge Representation and the Semantic Web, Editorial Board member of the Logical Methods in Computer Science (LMCS) Journal, for the areas of Database Theory and Logic for Knowledge Representation, and Area Editor of the Logic Journal of the Interest Group in Pure and Applied Logic (IGPL), for the area of Logic for Knowledge Representation and the Semantic Web, he has been co-Chair of the 29th International Workshop on Description Logics (DL 2016), since 2011 he is Member of the ACM SIGMOD Awards Committee, since 2006 he is Member of the Executive Committe of the ACM Principles of Database Systems (PODS), and since 2005 he is Member of the Sistemi Evoluti di Basi di Dati (SEBD) Steering Committe, he is also Member of the Scientific Advisory Board of BiCi –Bertinoro international Center for Informatics and Member of the Advisory Board of the European Research Institute in Service Science (ERISS). Riccardo Rosati is Member of the Editorial Board of Artificial Intelligence (Elsevier), Steering Committee Member of the International Workshop on Nonmonotonic Reasoning (NMR), since 2012.