Diego Calvanese | Free University of Bozen-Bolzano (original) (raw)
Papers by Diego Calvanese
Semantic technologies are rapidly changing the historical research. Over the last decades, an imm... more Semantic technologies are rapidly changing the historical research. Over the last decades, an immense amount of new quantifiable data have been accumulated, and made available in interchangeable formats, in social sciences and humanities, opening up new possibilities for solving old questions and posing new ones. This paper introduces a framework that eases the access of scholars to historical and cultural data about food production and commercial trade system during the Roman Empire, distributed across different data sources. The proposed approach relies on the Ontology-Based Data Access (OBDA) paradigm, where the different datasets are virtually integrated by a conceptual layer (an ontology) that provides to the user a clear point of access and a unified and unambiguous conceptual view.
Lecture Notes in Computer Science, 2013
Description Logics, Aug 1, 2001
One of the basic problems in the development of techniques for the semantic web is the integratio... more One of the basic problems in the development of techniques for the semantic web is the integration of ontologies. In this paper we deal with a situation where we have various local ontologies, developed independently from each other, and we are required to build an integrated, global ontology as a mean for extracting information from the local ones. In this context, the problem of how to specify the mapping between the global ontology and the local ontologies is a fundamental one, and its solution is essential for establishing an ...
Deductive and Object-Oriented Databases, 1995
One distinctive characteristic of object-oriented data models over traditional database systems i... more One distinctive characteristic of object-oriented data models over traditional database systems is that they provide more expressive power in schema definition. Nevertheless, the defining power of object-oriented models is still somewhat limited, mainly because it is commonly accepted that part of the semantics of the application can be represented within methods. The research work reported in this paper explores the possibility of enhancing the power of object-oriented data models in schema definition, thus offering more possibilities ...
Service-Oriented Computing-ICSOC 2003, 2003
The main focus of this paper is on automatic e-Service composition. We start by developing a fram... more The main focus of this paper is on automatic e-Service composition. We start by developing a framework in which the exported behavior of an e-Service is described in terms of its possible executions (execution trees). Then we specialize the framework to the case in which such exported behavior (ie, the execution tree of the e-Service) is represented by a finite state machine. In this specific setting, we analyze the complexity of synthesizing a composition, and develop sound and complete algorithms to check the existence of a ...
The Emerging Semantic Web—Selected Papers from the First Semantic Web Working Symposium, Mar 1, 2002
Abstract. One of the basic problems in the development of techniques for the semantic web is the ... more Abstract. One of the basic problems in the development of techniques for the semantic web is the integration of ontologies. Indeed, the web is constituted by a variety of information sources, each expressed over a certain ontology, and in order to extract information from such sources, their semantic integration and reconciliation in terms of a global ontology is required. In this paper, we address the fundamental problem of how to specify the mapping between the global ontology and the local ontologies. We argue that for capturing such ...
Networking and information systems journal, 1999
ABSTRACT. We extend the model for semi-structured data proposed in [BUN 97], where both databases... more ABSTRACT. We extend the model for semi-structured data proposed in [BUN 97], where both databases and schemas are represented as graphs, with the possibility of expressing different types of constraints on the nodes of the graphs. We discuss how the expressive power of the constraint language may influence the complexity of checking subsumption between schemas, and devise a polynomial algorithm for an interesting class of constraints. We then set up a framework for defining queries which are used to select graphs from a ...
2004 International Workshop on Description Logics, Jun 6, 2004
In this paper we study a DL rich enough to express UML class diagrams including ISA and disjointn... more In this paper we study a DL rich enough to express UML class diagrams including ISA and disjointness between classes (but not covering constraints), typing of associations, and participation and functional cardinality constraints. For such a DL, which we call DL-Lite, we propose novel reasoning techniques for a variety of tasks, notably including query containment and query answering for conjunctive queries over concepts and roles. The techniques are based on query containment under constraints typical of databases. A ...
Proceedings of the National Conference on Artificial Intelligence, Jul 9, 2005
We propose a new Description Logic, called DL-Lite, specifically tailored to capture basic ontolo... more We propose a new Description Logic, called DL-Lite, specifically tailored to capture basic ontology languages, while keeping low complexity of reasoning. Reasoning here means not only computing subsumption between concepts, and checking satisfiability of the whole knowledge base, but also answering complex queries (in particular, conjunctive queries) over the set of instances maintained in secondary storage. We show that in DL-Lite the usual DL reasoning tasks are polynomial in the size of the TBox, and query answering ...
Proceedings of the …, 1996
Recent proposals to improve the quality of interaction with the World Wide Web suggest considerin... more Recent proposals to improve the quality of interaction with the World Wide Web suggest considering the Web as a huge semistructured database, so that retrieving information can be supported by the task of database querying. Under this view, it is important to represent the form of both the network, and the documents placed in the nodes of the network. However, the current proposals do not pay sufficient attention to represent document structures and reasoning about them. In this paper, we address these problems ...
Proceedings of the National Conference on Artificial Intelligence, Jul 9, 2005
One of the most important lines of research in Description Logics (DLs) is concerned with the tra... more One of the most important lines of research in Description Logics (DLs) is concerned with the trade-off between expressive power and computational complexity of sound and complete reasoning. Research carried out in the past on this topic has shown that many DLs with efficient, ie, worstcase polynomial time, reasoning algorithms lack the modeling power required for capturing conceptual models and basic ontology languages, while most DLs with sufficient modeling power suffer from inherently worst-case exponential time behavior ...
INTERNATIONAL JOINT CONFERENCE ON ARTIFICIAL INTELLIGENCE, Jul 31, 1999
In the last years, the investigation on Description Logics (DLs) has been driven by the goal of a... more In the last years, the investigation on Description Logics (DLs) has been driven by the goal of applying them in several areas, such as, software engineering, information systems, databases, information integration, and intelligent access to the web. The modeling requirements arising in the above areas have stimulated the need for very rich languages, including fixpoint constructs to represent recursive structures. We study a DL comprising the most general form of fixpoint constructs on concepts, all classical concept forming ...
Proc. of the 20th Eur. Conf. on Artificial Intelligence (ECAI 2012), 2012
Abstract. We introduce description logic (DL) Knowledge and Action Bases (KAB), a mechanism that ... more Abstract. We introduce description logic (DL) Knowledge and Action Bases (KAB), a mechanism that provides both a semantically rich representation of the information on the domain of interest in terms of a DL KB and a set of actions to change such information over time, possibly introducing new objects. We resort to a variant of DL-Lite where UNA is not enforced and where equality between objects may be asserted and inferred. Actions are specified as sets of conditional effects, where conditions are based on epistemic queries ...
Semantic Web, 2011
In this paper we present MASTRO, a Java tool for ontology-based data access (OBDA) developed at S... more In this paper we present MASTRO, a Java tool for ontology-based data access (OBDA) developed at Sapienza Università di Roma and at the Free University of Bozen-Bolzano. MASTRO manages OBDA systems in which the ontology is specified in DL-LiteA, id, a logic of the DL-Lite family of tractable Description Logics specifically tailored to ontology-based data access, and is connected to external JDBC enabled data management systems through semantic mappings that associate SQL queries over the external data to the ...
Proceedings of the International Workshop on Design and Management of Data Warehouses (DMDW’99), Jun 1, 1999
Integration is one of the most important aspects of a Data Warehouse. When data passes from the s... more Integration is one of the most important aspects of a Data Warehouse. When data passes from the sources of the application-oriented operational environment to the Data Warehouse, possible inconsistencies and redundancies should be resolved, so that the warehouse is able to provide an integrated and reconciled view of data of the organization. We describe a novel approach to data integration and reconciliation, based on a conceptual representation of the Data Warehouse application domain. The main idea is to ...
PROCEEDINGS OF THE NATIONAL CONFERENCE ON ARTIFICIAL INTELLIGENCE, Jul 30, 2000
Answering queries using views amounts to computing the answer to a query having information only ... more Answering queries using views amounts to computing the answer to a query having information only on the extension of a set of precomputed queries (views). This problem is relevant in several fields, such as information integration, query optimization, and data warehousing, and has been studied recently in different settings. In this paper we address answering queries using views in a setting where intensional knowledge about the domain is represented using a very expressive Description Logic equipped with n-ary relations, ...
Semantic technologies are rapidly changing the historical research. Over the last decades, an imm... more Semantic technologies are rapidly changing the historical research. Over the last decades, an immense amount of new quantifiable data have been accumulated, and made available in interchangeable formats, in social sciences and humanities, opening up new possibilities for solving old questions and posing new ones. This paper introduces a framework that eases the access of scholars to historical and cultural data about food production and commercial trade system during the Roman Empire, distributed across different data sources. The proposed approach relies on the Ontology-Based Data Access (OBDA) paradigm, where the different datasets are virtually integrated by a conceptual layer (an ontology) that provides to the user a clear point of access and a unified and unambiguous conceptual view.
Lecture Notes in Computer Science, 2013
Description Logics, Aug 1, 2001
One of the basic problems in the development of techniques for the semantic web is the integratio... more One of the basic problems in the development of techniques for the semantic web is the integration of ontologies. In this paper we deal with a situation where we have various local ontologies, developed independently from each other, and we are required to build an integrated, global ontology as a mean for extracting information from the local ones. In this context, the problem of how to specify the mapping between the global ontology and the local ontologies is a fundamental one, and its solution is essential for establishing an ...
Deductive and Object-Oriented Databases, 1995
One distinctive characteristic of object-oriented data models over traditional database systems i... more One distinctive characteristic of object-oriented data models over traditional database systems is that they provide more expressive power in schema definition. Nevertheless, the defining power of object-oriented models is still somewhat limited, mainly because it is commonly accepted that part of the semantics of the application can be represented within methods. The research work reported in this paper explores the possibility of enhancing the power of object-oriented data models in schema definition, thus offering more possibilities ...
Service-Oriented Computing-ICSOC 2003, 2003
The main focus of this paper is on automatic e-Service composition. We start by developing a fram... more The main focus of this paper is on automatic e-Service composition. We start by developing a framework in which the exported behavior of an e-Service is described in terms of its possible executions (execution trees). Then we specialize the framework to the case in which such exported behavior (ie, the execution tree of the e-Service) is represented by a finite state machine. In this specific setting, we analyze the complexity of synthesizing a composition, and develop sound and complete algorithms to check the existence of a ...
The Emerging Semantic Web—Selected Papers from the First Semantic Web Working Symposium, Mar 1, 2002
Abstract. One of the basic problems in the development of techniques for the semantic web is the ... more Abstract. One of the basic problems in the development of techniques for the semantic web is the integration of ontologies. Indeed, the web is constituted by a variety of information sources, each expressed over a certain ontology, and in order to extract information from such sources, their semantic integration and reconciliation in terms of a global ontology is required. In this paper, we address the fundamental problem of how to specify the mapping between the global ontology and the local ontologies. We argue that for capturing such ...
Networking and information systems journal, 1999
ABSTRACT. We extend the model for semi-structured data proposed in [BUN 97], where both databases... more ABSTRACT. We extend the model for semi-structured data proposed in [BUN 97], where both databases and schemas are represented as graphs, with the possibility of expressing different types of constraints on the nodes of the graphs. We discuss how the expressive power of the constraint language may influence the complexity of checking subsumption between schemas, and devise a polynomial algorithm for an interesting class of constraints. We then set up a framework for defining queries which are used to select graphs from a ...
2004 International Workshop on Description Logics, Jun 6, 2004
In this paper we study a DL rich enough to express UML class diagrams including ISA and disjointn... more In this paper we study a DL rich enough to express UML class diagrams including ISA and disjointness between classes (but not covering constraints), typing of associations, and participation and functional cardinality constraints. For such a DL, which we call DL-Lite, we propose novel reasoning techniques for a variety of tasks, notably including query containment and query answering for conjunctive queries over concepts and roles. The techniques are based on query containment under constraints typical of databases. A ...
Proceedings of the National Conference on Artificial Intelligence, Jul 9, 2005
We propose a new Description Logic, called DL-Lite, specifically tailored to capture basic ontolo... more We propose a new Description Logic, called DL-Lite, specifically tailored to capture basic ontology languages, while keeping low complexity of reasoning. Reasoning here means not only computing subsumption between concepts, and checking satisfiability of the whole knowledge base, but also answering complex queries (in particular, conjunctive queries) over the set of instances maintained in secondary storage. We show that in DL-Lite the usual DL reasoning tasks are polynomial in the size of the TBox, and query answering ...
Proceedings of the …, 1996
Recent proposals to improve the quality of interaction with the World Wide Web suggest considerin... more Recent proposals to improve the quality of interaction with the World Wide Web suggest considering the Web as a huge semistructured database, so that retrieving information can be supported by the task of database querying. Under this view, it is important to represent the form of both the network, and the documents placed in the nodes of the network. However, the current proposals do not pay sufficient attention to represent document structures and reasoning about them. In this paper, we address these problems ...
Proceedings of the National Conference on Artificial Intelligence, Jul 9, 2005
One of the most important lines of research in Description Logics (DLs) is concerned with the tra... more One of the most important lines of research in Description Logics (DLs) is concerned with the trade-off between expressive power and computational complexity of sound and complete reasoning. Research carried out in the past on this topic has shown that many DLs with efficient, ie, worstcase polynomial time, reasoning algorithms lack the modeling power required for capturing conceptual models and basic ontology languages, while most DLs with sufficient modeling power suffer from inherently worst-case exponential time behavior ...
INTERNATIONAL JOINT CONFERENCE ON ARTIFICIAL INTELLIGENCE, Jul 31, 1999
In the last years, the investigation on Description Logics (DLs) has been driven by the goal of a... more In the last years, the investigation on Description Logics (DLs) has been driven by the goal of applying them in several areas, such as, software engineering, information systems, databases, information integration, and intelligent access to the web. The modeling requirements arising in the above areas have stimulated the need for very rich languages, including fixpoint constructs to represent recursive structures. We study a DL comprising the most general form of fixpoint constructs on concepts, all classical concept forming ...
Proc. of the 20th Eur. Conf. on Artificial Intelligence (ECAI 2012), 2012
Abstract. We introduce description logic (DL) Knowledge and Action Bases (KAB), a mechanism that ... more Abstract. We introduce description logic (DL) Knowledge and Action Bases (KAB), a mechanism that provides both a semantically rich representation of the information on the domain of interest in terms of a DL KB and a set of actions to change such information over time, possibly introducing new objects. We resort to a variant of DL-Lite where UNA is not enforced and where equality between objects may be asserted and inferred. Actions are specified as sets of conditional effects, where conditions are based on epistemic queries ...
Semantic Web, 2011
In this paper we present MASTRO, a Java tool for ontology-based data access (OBDA) developed at S... more In this paper we present MASTRO, a Java tool for ontology-based data access (OBDA) developed at Sapienza Università di Roma and at the Free University of Bozen-Bolzano. MASTRO manages OBDA systems in which the ontology is specified in DL-LiteA, id, a logic of the DL-Lite family of tractable Description Logics specifically tailored to ontology-based data access, and is connected to external JDBC enabled data management systems through semantic mappings that associate SQL queries over the external data to the ...
Proceedings of the International Workshop on Design and Management of Data Warehouses (DMDW’99), Jun 1, 1999
Integration is one of the most important aspects of a Data Warehouse. When data passes from the s... more Integration is one of the most important aspects of a Data Warehouse. When data passes from the sources of the application-oriented operational environment to the Data Warehouse, possible inconsistencies and redundancies should be resolved, so that the warehouse is able to provide an integrated and reconciled view of data of the organization. We describe a novel approach to data integration and reconciliation, based on a conceptual representation of the Data Warehouse application domain. The main idea is to ...
PROCEEDINGS OF THE NATIONAL CONFERENCE ON ARTIFICIAL INTELLIGENCE, Jul 30, 2000
Answering queries using views amounts to computing the answer to a query having information only ... more Answering queries using views amounts to computing the answer to a query having information only on the extension of a set of precomputed queries (views). This problem is relevant in several fields, such as information integration, query optimization, and data warehousing, and has been studied recently in different settings. In this paper we address answering queries using views in a setting where intensional knowledge about the domain is represented using a very expressive Description Logic equipped with n-ary relations, ...
Description logics are embodied in several knowledge-based systems and are used to develop variou... more Description logics are embodied in several knowledge-based systems and are used to develop various real-life applications. Now in paperback, The Description Logic Handbook provides a thorough account of the subject, covering all aspects of research in this field, namely: theory, implementation, and applications. Its appeal will be broad, ranging from more theoretically oriented readers, to those with more practically oriented interests who need a sound and modern understanding of knowledge representation systems based on description logics. As well as general revision throughout the book, this new edition presents a new chapter on ontology languages for the semantic web, an area of great importance for the future development of the web. In sum, the book will serve as a unique resource for the subject, and can also be used for self-study or as a reference for knowledge representation and artificial intelligence courses.