Diego Calvanese

Diego Calvanese
Free University of Bozen-Bolzano | Unibolzano · Faculty of Computer Science

PhD

About

494
Publications
76,036
Reads
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22,909
Citations
Citations since 2017
75 Research Items
5266 Citations
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201720182019202020212022202302004006008001,000
201720182019202020212022202302004006008001,000
201720182019202020212022202302004006008001,000
Introduction
My main research interests are logics for knowledge representation and reasoning, virtual knowledge graphs for data access and integration (also known as ontology-based data access and integration), and modeling and verification of data-aware processes. All my publications are available for download as pdf files from my personal homepage at the Free University of Bozen-Bolzano.
Additional affiliations
November 2003 - December 2014
Free University of Bozen-Bolzano
Position
  • Professor (Associate)
November 2000 - October 2003
Sapienza University of Rome
Position
  • Research Assistant

Publications

Publications (494)
Article
Full-text available
It may be tempting for researchers to stick to incremental extensions of their current work to plan future research activities. Yet there is also merit in realizing the grand challenges in one’s field. This paper presents an overview of the nine major research problems for the Business Process Management discipline. These challenges have been colle...
Article
AI-Augmented Business Process Management Systems (ABPMSs) are an emerging class of process-aware information systems, empowered by trustworthy AI technology. An ABPMS enhances the execution of business processes with the aim of making these processes more adaptable, proactive, explainable, and context-sensitive. This manifesto presents a vision for...
Article
Full-text available
This study concerns the analysis of the modulation of Chronic Myeloid Leukemia (CML) cell model K562 transcriptome following transfection with the tumor suppressor gene encoding for Protein Tyrosine Phosphatase Receptor Type G (PTPRG) and treatment with the tyrosine kinase inhibitor (TKI) Imatinib. Specifically, we aimed at identifying genes whose...
Conference Paper
We address the problem of model checking first-order dynamic systems where new objects can be injected in the active domain during execution. Notable examples are systems induced by a first-order action theory, e.g., expressed in the Situation Calculus. Recent results have shown that, under the state-boundedness assumption, such systems, in spite o...
Article
Full-text available
Uniform interpolants were largely studied in non-classical propositional logics since the nineties, and their connection to model completeness was pointed out in the literature. A successive parallel research line inside the automated reasoning community investigated uniform quantifier-free interpolants (sometimes referred to as “covers”) in first-...
Article
A full-fledged data exploration system must combine different access modalities with a powerful concept of guiding the user in the exploration process, by being reactive and anticipative both for data discovery and for data linking. Such systems are a real opportunity for our community to cater to users with different domain and data science expert...
Preprint
Full-text available
Augmented Business Process Management Systems (ABPMSs) are an emerging class of process-aware information systems that draws upon trustworthy AI technology. An ABPMS enhances the execution of business processes with the aim of making these processes more adaptable, proactive, explainable, and context-sensitive. This manifesto presents a vision for...
Article
Full-text available
Integrating heterogeneous geospatial data sources is important in various domains like smart cities, urban planning and governance, but remains a challenging research problem. In particular, the production of high-quality integrated data from multiple sources requires an understanding of their respective characteristics and a systematic assessment...
Article
Full-text available
Uniform interpolants have been largely studied in non-classical propositional logics since the nineties; a successive research line within the automated reasoning community investigated uniform quantifier-free interpolants (sometimes referred to as “covers”) in first-order theories. This further research line is motivated by the fact that uniform i...
Article
With the advancement of Semantic Technologies, large geospatial data sources have been increasingly published as Linked data on the Web. The LinkedGeoData project is one of the most prominent such projects to create a large knowledge graph from OpenStreetMap (OSM) with global coverage and interlinking of other data sources. In this paper, we report...
Article
Full-text available
In this tutorial, we learn how to set up and exploit the virtual knowledge graph (VKG) approach to access data stored in relational legacy systems and to enrich such data with domain knowledge coming from different heterogeneous (biomedical) resources. The VKG approach is based on an ontology that describes a domain of interest in terms of a vocabu...
Preprint
In the context of verification of data-aware processes (DAPs), a formal approach based on satisfiability modulo theories (SMT) has been considered to verify parameterised safety properties of so-called artifact-centric systems. This approach requires a combination of model-theoretic notions and algorithmic techniques based on backward reachability....
Chapter
We propose a method for automatically extracting semantics from data sources. The availability of multiple data sources on the one hand and the lack of proper semantic documentation of such data sources on the other hand call for new strategies in integrating data sources by extracting semantics from the data source itself rather than from its docu...
Preprint
Full-text available
A full-fledged data exploration system must combine different access modalities with a powerful concept of guiding the user in the exploration process, by being reactive and anticipative both for data discovery and for data linking. Such systems are a real opportunity for our community to cater to users with different domain and data science expert...
Preprint
Full-text available
Virtual Knowledge Graphs (VKG) constitute one of the most promising paradigms for integrating and accessing legacy data sources. A critical bottleneck in the integration process involves the definition, validation, and maintenance of mappings that link data sources to a domain ontology. To support the management of mappings throughout their entire...
Chapter
Analyses of products during manufacturing are essential to guarantee their quality. In complex industrial settings, such analyses require to use data coming from many different and highly heterogeneous machines, and thus are affected by the data integration challenge. In this work, we show how this challenge can be addressed by relying on semantic...
Chapter
Ontop is a popular open-source virtual knowledge graph system that can expose heterogeneous data sources as a unified knowledge graph. Ontop has been widely used in a variety of research and industrial projects. In this paper, we describe the challenges, design choices, new features of the latest release of Ontop v4, summarizing the development eff...
Conference Paper
Analyses of products during manufacturing are essential to guarantee their quality. In complex industrial settings, such analyses require to use data coming from many different and highly heterogeneous machines, and thus are affected by the data integration challenge. In this work, we show how this challenge can be addressed by relying on semantic...
Article
Full-text available
In a variety of applications relying on geospatial data, getting insights into heterogeneous geodata sources is crucial for decision making, but often challenging. The reason is that it typically requires combining information coming from different sources via data integration techniques, and then making sense out of the combined data via sophistic...
Conference Paper
Full-text available
Counting answers to a query is an operation supported by virtually all database management systems. In this paper we focus on counting answers over a Knowledge Base (KB), which may be viewed as a database enriched with background knowledge about the domain under consideration. In particular, we place our work in the context of Ontology-Mediated Que...
Chapter
Uniform interpolants were largely studied in non-classical propositional logics since the nineties, and their connection to model completeness was pointed out in the literature. A successive parallel research line inside the automated reasoning community investigated uniform quantifier-free interpolants (sometimes referred to as “covers”) in first-...
Preprint
Full-text available
Counting answers to a query is an operation supported by virtually all database management systems. In this paper we focus on counting answers over a Knowledge Base (KB), which may be viewed as a database enriched with background knowledge about the domain under consideration. In particular, we place our work in the context of Ontology-Mediated Que...
Article
The annual International Joint Conference on Rules and Reasoning (RuleML+RR) is an international conference on research, applications, languages and standards for rule technologies, rule-based programming and rule-based systems including production rules systems, logic programming rule engines, as well as business-rule engines and management system...
Article
In recent times, satisfiability modulo theories (SMT) techniques gained increasing attention and obtained remarkable success in model-checking infinite-state systems. Still, we believe that whenever more expressivity is needed in order to specify the systems to be verified, more and more support is needed from mathematical logic and model theory. T...
Preprint
Full-text available
Knowledge bases (KBs) are not static entities: new information constantly appears and some of the previous knowledge becomes obsolete. In order to reflect this evolution of knowledge, KBs should be expanded with the new knowledge and contracted from the obsolete one. This problem is well-studied for propositional but much less for first-order KBs....
Preprint
In ESOP 2008, Gulwani and Musuvathi introduced a notion of cover and exploited it to handle infinite-state model checking problems. Motivated by applications to the verification of data-aware processes, we proved in a previous paper that covers are strictly related to model completions, a well-known topic in model theory. In this paper we investiga...
Book
This book constitutes the proceedings of the International Joint Conference on Rules and Reasoning, RuleML+RR 2019, held in Bolzano, Italy, during September 2019. This is the third conference of a new series, joining the efforts of two existing conference series, namely “RuleML” (International Web Rule Symposium) and “RR” (Web Reasoning and Rule Sy...
Chapter
In ESOP 2008, Gulwani and Musuvathi introduced a notion of cover and exploited it to handle infinite-state model checking problems. Motivated by applications to the verification of data-aware processes, we show how covers are strictly related to model completions, a well-known topic in model theory. We also investigate the computation of covers wit...
Article
Full-text available
Knowledge bases (KBs) are not static entities: new information constantly appears and some of the previous knowledge becomes obsolete. In order to reflect this evolution of knowledge, KBs should be expanded with the new knowledge and contracted from the obsolete one. This problem is well-studied for propositional but much less for first-order KBs....
Conference Paper
Full-text available
Ontology-based data access (OBDA) is a popular paradigm for querying heterogeneous data sources by connecting them through mappings to an ontology. In OBDA, it is often difficult to reconstruct why a tuple occurs in the answer of a query. We address this challenge by enriching OBDA with provenance semirings, taking inspiration from database theory....
Chapter
We propose DAB – a data-aware extension of BPMN where the process operates over case and persistent data (partitioned into a read-only database called catalog and a read-write database called repository). The model trades off between expressiveness and the possibility of supporting parameterized verification of safety properties on top of it. Speci...
Preprint
Full-text available
Ontology-based data access (OBDA) is a popular paradigm for querying heterogeneous data sources by connecting them through mappings to an ontology. In OBDA, it is often difficult to reconstruct why a tuple occurs in the answer of a query. We address this challenge by enriching OBDA with provenance semirings, taking inspiration from database theory....
Chapter
The issue of cooperation, integration, and coordination between information peers has been addressed over the years both in the context of the Semantic Web and in several other networked environments, including data integration, Peer-to-Peer and Grid computing, service-oriented computing, distributed agent systems, and collaborative data sharing. O...
Chapter
Model Completeness is a classical topic in model-theoretic algebra, and its inspiration sources are areas like algebraic geometry and field theory. Yet, recently, there have been remarkable applications in computer science: these applications range from combined decision procedures for satisfiability and interpolation, to connections between tempor...
Preprint
We propose DAB -- a data-aware extension of BPMN where the process operates over case and persistent data (partitioned into a read-only database called catalog and a read-write database called repository). The model trades off between expressiveness and the possibility of supporting parameterized verification of safety properties on top of it. Spec...
Preprint
We propose DAB -- a data-aware extension of the BPMN de-facto standard with the ability of operating over case and persistent data (partitioned into a read-only catalog and a read-write repository), and that balances between expressiveness and the possibility of supporting parameterized verification of safety properties on top of it. In particular,...
Chapter
It is known that the engineering of information systems usually requires a huge effort in integrating master data and business processes. Existing approaches, both from academia and the industry, typically come with ad-hoc abstractions to represent and interact with the data component. This has two disadvantages: (i) an existing database (DB) canno...
Article
Full-text available
In this paper, we present the virtual knowledge graph (VKG) paradigm for data integration and access, also known in the literature as Ontology-based Data Access. Instead of structuring the integration layer as a collection of relational tables, the VKG paradigm replaces the rigid structure of tables with the flexibility of graphs that are kept virt...
Article
The Decision Model and Notation (DMN) is a recent Object Management Group standard for the elicitation and representation of decision models and for managing their interconnection with business processes. DMN builds on the notion of decision tables and their combination into more complex decision requirements graphs (DRGs), which bridge between bus...
Chapter
OPTIONAL is a key feature in SPARQL for dealing with missing information. While this operator is used extensively, it is also known for its complexity, which can make efficient evaluation of queries with OPTIONAL challenging. We tackle this problem in the Ontology-Based Data Access (OBDA) setting, where the data is stored in a SQL relational databa...
Chapter
The database (DB) landscape has been significantly diversified during the last decade, resulting in the emergence of a variety of non-relational (also called NoSQL) DBs, e.g., xml and json-document DBs, key-value stores, and graph DBs. To enable access to such data, we generalize the well-known ontology-based data access (OBDA) framework so as to a...
Chapter
Ontology-based Data Access (OBDA) is a by now well-established paradigm that relies on conceptually representing a domain of interest to provide access to relational data sources. The conceptual representation is given in terms of a domain schema (also called an ontology), which is linked to the data sources by means of declarative mapping specific...
Article
In this paper we describe VIG, a data scaler for Ontology-Based Data Access (OBDA) benchmarks. Data scaling is a relatively recent approach, proposed in the database community, that allows for quickly scaling an input data instance to s times its size, while preserving certain application-specific characteristics. The advantages of the scaling appr...
Preprint
Full-text available
During the last two decades, increasing attention has been given to the challenging problem of resolving the dichotomy between business process management and master data management. Consequently, a substantial number of data-centric models of dynamic systems have been brought forward. However, the control-flow abstractions they adopt are ad-hoc, a...
Conference Paper
We present Ontop-temporal, an extension of the ontology-based data access system Ontop for query answering with temporal data and ontologies. Ontop is a system to answer SPARQL queries over various data stores, using standard R2RML mappings and an OWL2QL domain ontology to produce high-level conceptual views over the raw data. The Ontop-temporal ex...
Conference Paper
Recently, semantic technologies have been successfully deployed to overcome the typical difficulties in accessing and integrating data stored in different kinds of legacy sources. In particular, knowledge graphs are being used as a mechanism to provide a uniform representation of heterogeneous information. Such graphs represent data in the RDF form...
Conference Paper
Full-text available
During the last two decades, (structural) conceptual schemas have been increasingly adopted not only to understand and document the relevant aspects of an application domain at a high level of abstraction, but also as live, computational artifacts. In particular, the paradigm of Ontology-Based Data Access (OBDA) exploits conceptual schemas (also ca...
Preprint
Full-text available
The Decision Model and Notation (DMN) is a recent OMG standard for the elicitation and representation of decision models, and for managing their interconnection with business processes. DMN builds on the notion of decision table, and their combination into more complex decision requirements graphs (DRGs), which bridge between business process model...
Conference Paper
We present the framework of ontology-based data access, a semantic paradigm for providing a convenient and user-friendly access to data repositories, which has been actively developed and studied in the past decade. Focusing on relational data sources, we discuss the main ingredients of ontology-based data access, key theoretical results, technique...
Chapter
We present the framework of ontology-based data access, a semantic paradigm for providing a con- venient and user-friendly access to data reposito- ries, which has been actively developed and stud- ied in the past decade. Focusing on relational data sources, we discuss the main ingredients of ontology-based data access, key theoretical results, tec...
Preprint
We study verification over a general model of data-aware processes, to assess (parameterized) safety properties irrespectively of the initial database instance. We rely on an encoding into array-based systems, which allows us to check safety by adapting backward reachability, establishing for the first time a correspondence with model checking base...
Preprint
Running verification tasks in database driven systems requires solving quantifier elimination problems (not including arithmetic) of a new kind. In this paper, we supply quantifier elimination algorithms based on Knuth-Bendix completions and begin studying the complexity of these problems, arguing that they are much better behaved than their arithm...
Preprint
OPTIONAL is a key feature in SPARQL for dealing with missing information. While this operator is used extensively, it is also known for its complexity, which can make efficient evaluation of queries with OPTIONAL challenging. We tackle this problem in the Ontology-Based Data Access (OBDA) setting, where the data is stored in a SQL relational databa...
Chapter
In this paper, we study how to efficiently integrate multiple relational databases using an ontology-based approach. In ontology-based data integration (OBDI) an ontology provides a coherent view of multiple databases, and SPARQL queries over the ontology are rewritten into (federated) SQL queries over the underlying databases. Specifically, we add...
Chapter
We address the problem of query answering with ontologies over databases. We consider first-order ontology systems playing the role of a conceptual model of a database represented as a classical finite relational store, either with an open world or a closed world reading. Queries over the conceptual signature are reformulated into queries over the...
Article
We consider μL, μLa, and μLp, three variants of the first-order μ-calculus studied in verification of data-aware processes, that differ in the form of quantification on objects across states. Each of these three logics has a distinct notion of bisimulation. We show that the three notions collapse for generic dynamic systems, which include all state...
Article
The Decision Model and Notation (DMN) is a standard notation to capture decision logic in business applications. A central construct in DMN is that of a decision table. The increasing use of DMN decision tables to capture critical business knowledge raises the need to support analysis and refactoring tasks on these tables. This article puts forward...
Conference Paper
SPARQL query answering in ontology-based data access (OBDA) is carried out by translating into SQL queries over the data source. Standard translation techniques try to transform the user query into a union of conjunctive queries (UCQ), following the heuristic argument that UCQs can be efficiently evaluated by modern relational database engines. In...
Conference Paper
Full-text available
Process mining techniques require the input data to be explicitly structured in the form of an event log. Unfortunately, in many real world settings, such event logs are not explicitly given, but they are implicitly stored in legacy information systems. Therefore, to enable process mining, there is a need to support the data preparation and the log...
Technical Report
Full-text available
In ontology-based data access (OBDA), users are provided with a conceptual view of a (relational) data source that abstracts away details about data storage. This conceptual view is realized through an ontology that is connected to the data source through declarative mappings, and query answering is carried out by translating the user queries over...
Conference Paper
Full-text available
Process mining aims at discovering, monitoring, and improving business processes by extracting knowledge from event logs. In this respect, process mining can be applied only if there are proper event logs that are compatible with accepted standards, such as extensible event stream (XES). Unfortunately, in many real world set-ups, such event logs ar...
Conference Paper
Full-text available
The Decision Model and Notation (DMN) is a recent OMG standard for the elicitation and representation of decision models. DMN builds on the notion of decision table, which consists of columns representing the inputs and outputs of a decision, and rows denoting rules. DMN models work under the assumption of complete information, and do not support i...
Chapter
Process mining is an emerging area that synergically combines model-based and data-oriented analysis techniques to obtain useful insights on how business processes are executed within an organization. Through process mining, decision makers can discover process models from data, compare expected and actual behaviors, and enrich models with key info...
Article
Full-text available
In April 2016, a community of researchers working in the area of Principles of Data Management (PDM) joined in a workshop at the Dagstuhl Castle in Germany. The workshop was organized jointly by the Executive Committee of the ACM Symposium on Principles of Database Systems (PODS) and the Council of the International Conference on Database Theory (I...
Article
Full-text available
We present a new metric temporal logic HornMTL over dense time and its datalog extension datalogMTL. The use of datalogMTL is demonstrated in the context of ontology-based data access over meteorological data. We show decidability of answering ontology-mediated queries for a practically relevant non-recursive fragment of datalogMTL. Finally, we dis...
Book
This volume contains some lecture notes of the 12th Reasoning Web Summer School (RW 2016), held in Aberdeen, UK, in September 2016. In 2016, the theme of the school was “Logical Foundation of Knowledge Graph Construction and Query Answering”. The notion of knowledge graph has become popular since Google started to use it to improve its search engin...
Conference Paper
We recall the key abstractions and models on which the major approaches to software specification rely, using Meyer’s forces of computation as dimensions of comparison. Based on the identified strengths and lacks, we introduce data-awareness and of norm-awareness as recommended properties, explaining the advantages they bring about. We show that mu...
Conference Paper
Full-text available
In the database community Polystores is an emerging and promising approach for data federation that aims at designing a unified querying layer over multiple data models. In the Semantic Web community a similar in spirit approach of Ontology-Based Data Access (OBDA) has been recently proposed, attracted a lot of attention, and proved its success in...
Article
Full-text available
In recent years, a plethora of foundational results and corresponding techniques and tools has been developed to support the modeling, analysis, execution and improvement of business processes along their entire lifecycle. A major shortcoming of the analysis techniques is that they solely focus on the control-flow dimension of the process, omitting...
Conference Paper
The temporal dimension of data, which contains such important information as duration or sequence of events and is present in many applications of ontology-based data access (OBDA) concerned with logs or streams, is getting growing attention in the community. To give a proper treatment to the events occurring in the data from the ontological perspe...