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Publications
Publications (138)
The popularity of Knowledge Graphs (KGs) both in industry and academia owes credit to their flexible data model, suitable for data integration from multiple sources. Several KG-based applications such as trust assessment or view maintenance on dynamic data rely on the ability to compute provenance explanations for query results. The how-provenance...
The wine industry has evolved thanks to the introduction of digital technologies in every aspect of the wine production chain and the emerging need of the food industry for qualitative, sustainable, and safe products. As a result, the incorporation of digital services that facilitate access to related data of wine products is crucial for wine enter...
The wine industry has evolved thanks to the introduction of digital technologies in every aspect of the wine production chain and the emerging need of the food industry for qualitative, sustainable, and safe products. As a result, the incorporation of digital services that facilitate access to related data of wine products is crucial for wine enter...
The exchange of comments, opinions, and arguments in blogs, forums, social media, wikis, and review websites has transformed the Web into a modern agora, a virtual place where all types of debates take place. This wealth of information remains mostly unexploited: due to its textual form, such information is difficult to automatically process and an...
argumentation frameworks (AAFs), introduced by Dung (1995, Artif. Intell., 228, 321–357), enabled a new way of reasoning with arguments, which does not take into account the internal structure of arguments but only how they are related to each other. The only form of relation considered in AAFs is a binary attack relation on the set of arguments. F...
Readers, as well as journalists, are overwhelmed with the information available in online news articles, making it very difficult to verify and validate their content. An important tool to support readers in this task is that of named entity linking (NEL), i.e., semantically annotating entities mentioned in text with entities described in knowledge...
Argumentative discourse rarely consists of opinions whose claims apply universally. As with logical statements, an argument applies to specific objects in the universe or relations among them, and may have exceptions. In this paper, we propose an argumentation formalism that allows associating arguments with a domain of application. Appropriate sem...
Digital applications typically describe their privacy policy in lengthy and vague documents (called PrPs), but these are rarely read by users, who remain unaware of privacy risks associated with the use of these digital applications. Thus, users need to become more aware of digital applications’ policies and, thus, more confident about their choice...
CAP-A is offering socio-technical tools to promote collective awareness and informed consent, whereby data collection and use by digital products are driven by the expectations and needs of the consumers themselves.
Deception detection is a task with many applications both in direct physical and in computer-mediated communication. Our focus is on automatic deception detection in text across cultures. We view culture through the prism of the individualism/collectivism dimension and we approximate culture by using country as a proxy. Having as a starting point r...
Recent extensions of the Event Calculus resulted in powerful formalisms, able to reason about a multitude of commonsense phenomena in causal domains, involving epistemic notions, functional fluents and probabilistic aspects, among others. Less attention has been paid to the problem of automatically revising (correcting) a Knowledge Base when an obs...
Consumers are largely unaware regarding the use being made to the data that they generate through smart devices, or their GDPR-compliance, since such information is typically hidden behind vague privacy policy documents, which are often lengthy, difficult to read (containing legal terms and definitions) and frequently changing. This paper describes...
The utilisation of personal data by mobile apps is often hidden behind vague Privacy Policy documents, which are typically lengthy, difficult to read (containing legal terms and definitions) and frequently changing. This paper discusses a suite of tools developed in the context of the CAP-A project, aiming to harness the collective power of users t...
Rewarding people is common in several contexts, such as human resource management and crowdsourcing applications. However, designing a reward strategy is not straightforward, as it requires considering different parameters. These parameters include, for example, management of rewarding tasks and identifying critical features, such as the type of re...
The field of Computational Argumentation is well-tailored to approach commonsense reasoning, due to its ability to model contradictory information. In this paper, we present preliminary work on how an argumentation framework can explicitly model commonsense knowledge, both at a logically structured and at an abstract level. We discuss the correlati...
We proposed the European Laboratory for Gravitation and Atom-interferometric Research (ELGAR), an array of atom gradiometers aimed at studying space-time and gravitation with the primary goal of observing gravitational waves (GWs) in the infrasound band with a peak strain sensitivity of $3.3 \times 10^{-22}/\sqrt{\text{Hz}}$ at 1.7 Hz. In this pape...
Rewarding people is common in several contexts, such as human resource management and crowdsourcing applications. However, designing a reward strategy is not straightforward, as it requires considering different parameters. These parameters include, for example, management of rewarding tasks and identifying critical features, such as the type of re...
This book constitutes the revised selected papers of the 13th International Workshop on Information Search, Integration and Personalization, ISIP 2019, held in Heraklion, Greece, in May 2019.
The volume presents 11 revised full papers, which were carefully reviewed and selected from 16 papers submitted to these post-conference proceedings. The pap...
ECAVI (Event Calculus Analysis and VIsualisation), is a domain independent visual modelling tool for designing dynamic domains in the Event Calculus. ECAVI is mainly addressed to inexperienced modellers,
aiming to acquaint them with the features of the Event Calculus (and consequently commonsense reasoning) and to guide them during the process of d...
Gravitational Waves (GWs) were observed for the first time in 2015, one century after Einstein predicted their existence. There is now growing interest to extend the detection bandwidth to low frequency. The scientific potential of multi-frequency GW astronomy is enormous as it would enable to obtain a more complete picture of cosmic events and mec...
It has been argued that Dung's classical Abstract Argumentation Framework (AAF) model is not appropriate for capturing “joint attacks”, a feature that is inherent in several contexts and applications. The model proposed by Nielsen and Parsons in [1], often referred to as “framework with sets of attacking arguments” (SETAF), fills this gap by introd...
In an increasingly instrumented and inter-connected digital world, citizens generate vast amounts of data, much of it being valuable and a significant part of it being personal. However, controlling who can collect it, limiting what they can do with it, and determining how best to protect it, remain deeply undecided issues. This paper proposes CAPr...
The goal of our research has been to integrate existing information systems and to design and implement a prototype of a digital personal travel assistant for travelers, called Travel Companion. Travel Companion assists a traveler through various guidance functions, and offers personalized reminders and recommendations, which are based on the trave...
The CAPrice initiative brings to the fore the creativity of the community towards privacy via specific co-creation tools (structured debates, annotation tools, reward mechanisms and others). Our objective is to improve citizen awareness on privacy issues, and leverage this awareness to motivate the market to adopt more privacy-friendly practices.
The aggregation of heterogeneous data from different institutions in cultural heritage and e-science has the potential to create rich data resources useful for a range of different purposes, from research to education and public interests. In this paper, we present the X3ML framework, a framework for information integration that handles effectively...
A vast amount of opinions are surfacing on the Web but the lack of mechanisms for managing them leads to confusing and often chaotic dialogues. This creates the need for further semantic infrastructure and analysis of the views expressed in large-volume discussions. In this paper, we describe a web platform for modeling and analyzing argumentative...
Linking geo-spatial entities is targeted only by a limited number of link discovery benchmarks. Linking spatial resources requires techniques that differ from the classical, mostly string-based approaches. In particular, considering the topology of the spatial resources and the topological relations between them is of central importance to systems...
Publication management systems can be instrumental in disseminating research results across academia and industry, by providing facilities for uploading, editing and searching for publications. Usually, these systems can be used by individuals to assist them in their research or by organizations to help them classify and promote their publication i...
We introduce ArgQL, a declarative query language, which performs on a data model designed according to the principles of argumentation. Its syntax is based on Cypher (language for graph databases) and SPARQL 1.1 and is adjusted for querying dialogues, composed by sets of arguments and their interrelations. We use formal semantics to show how querie...
Bias in online information has recently become a pressing issue, with search engines, social networks and recommendation services being accused of exhibiting some form of bias. In this vision paper, we make the case for a systematic approach towards measuring bias. To this end, we discuss formal measures for quantifying the various types of bias, w...
The goal of this survey is to present the state of the art instance matching benchmarks for Linked Data. We introduce the principles of benchmark design for instance matching systems, discuss the dimensions and characteristics of an instance matching benchmark, provide a comprehensive overview of existing benchmarks, as well as benchmark generators...
Users' reviews, comments and votes on the Social Web form the modern version of word-of-mouth communication, which has a huge impact on people?s habits and businesses. Nonetheless, there are only few attempts to formally model and analyze them using Computational Models of Argument, which achieved a first significant step in bringing these two fiel...
Tracking the provenance of information published on the Web is of crucial importance for effectively supporting trustworthiness, accountability and repeatability in the Web of Data. Although extensive work has been done on computing the provenance for SPARQL queries, little research has been conducted for the case of SPARQL updates. This paper prop...
The discovery of optimal or close to optimal query plans for SPARQL queries is a difficult and challenging problem for query optimisers of RDF engines. Despite the growing volume of work on optimising SPARQL query answering, using heuristics or data statistics (such as cardinality estimations) there is little effort on the use of OWL constructs for...
D2V, a research prototype for analysing the dynamics of Linked Open Data, has been used to study the evolution of biomedical datasets, such as the Experimental Factor Ontology (EFO) and the Gene Ontology (GO). Datasets are continuously evolving over time as our knowledge increases. Biomedical datasets in particular have undergone rapid changes in r...
The dynamic nature of the data on the Web gives rise to a multitude of problems related to the description and analysis of the evolution of such data. Traditional approaches for identifying and analyzing changes are descriptive, focus-ing on the provision of a " delta " that describes the changes and often overwhelming the user with loads of inform...
Ambient intelligence (AmI) proposes pervasive information systems composed of autonomous agents embedded within the environment who, in orchestration, complement human activity in an intelligent manner. As such, it is an interesting and challenging application area for many computer science fields and approaches. A critical issue in such applicatio...
The advances in healthcare and information technology are shifting more and more the ownership of data from medical institutions and doctors to individual citizens. However, since the medical information of an individual is con�dential, the only basis for sharing it, is through prior informed consent which will regulate access to his private health...
One of the main challenges in the Data Web is the identification of instances that refer to the same real-world entity. Choosing the right framework for this purpose remains tedious, as current instance matching benchmarks fail to provide end users and developers with the necessary insights pertaining to how current frameworks behave when dealing w...
The dynamic nature of Web data gives rise to the need of understanding and analyzing the dynamics of individual datasets. As a matter of fact, the value of a dynamic dataset lies not only in its content, but also in its evolution history, which in some applications (e.g., trend analysis and identification), is more important than the data itself. I...
The dynamic nature of Web data gives rise to a multitude of problems related to the description and analysis of the evolution of RDF datasets, which are important to a large number of users and domains, such as, the curators of biological information where changes are constant and interrelated. In this paper, we propose a framework that enables ide...
http://ceur-ws.org/Vol-1545/oaei15_paper0.pdf
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Ontology matching consists of finding correspondences between semantically
related entities of two ontologies. OAEI campaigns aim at comparing
ontology matching systems on precisely defined test cases. These test cases can
use ontologies of different nature (from simple thesauri to expr...
The aggregation of heterogeneous data from different institutions
in cultural heritage and e-science has the potential to create rich
data resources useful for a range of different purposes, from research to
education and public interests. In this paper, we present the architecture
and functionality of X3ML data exchange framework, that handles
eff...
The architectural choices behind the Data Web have led to the publication of large interrelated data sets that contain different descriptions for the same real-world objects. Due to the mere size of current online datasets, such duplicate instances are most commonly detected (semi-)automatically using instance matching frameworks. Choosing the righ...
The architectural choices behind the Data Web have led to the publication of large interrelated data sets that contain different descriptions for the same real-world objects. Due to the mere size of current online datasets, such duplicate instances are most commonly detected (semi-)automatically using instance matching frameworks. Choosing the righ...
We show how defeasible reasoning can be embedded into ABF. Differently from other proposals, we do not encode the conflict resolution mechanism for defeasible rules into the ABF’s deductive systems. Instead, we formalize the notions of conflict and conflict resolution and make them part of the extended ABF framework (XABF). This improves the contro...
The dynamic nature of Web data gives rise to a multitude of problems related
to the identification, computation and management of the evolving versions and
the related changes. In this paper, we consider the problem of change
recognition in RDF datasets, i.e., the problem of identifying, and when
possible give semantics to, the changes that led fro...
Ontology evolution aims at maintaining an ontology up to date with respect to changes in the domain that it models or novel requirements of information systems that it enables. The recent industrial adoption of Semantic Web techniques, which rely on ontologies, has led to the increased importance of the ontology evolution research. Typical approach...
The dynamic nature of Web data gives rise to a multitude of problems related to the description and analysis of the evolution of RDF datasets, which are important to a large number of users and domains, such as, the curators of biological information where changes are constant and interrelated. In this paper, we propose a framework that enables ide...
The dynamic nature of web data brings forward the need for main-taining data versions as well as identifying semantically rich changes between them. In this paper, we advocate the need for supporting complex changes in evolving RDF(S) knowledge bases. We outline the basic challenges and provide solution insights through a real-world example from th...
Several logical formalisms have been proposed in the literature for expressing structural and semantic integrity constraints of Linked Open Data (LOD). Still, the integrity of the datasets published in the LOD cloud needs to be improved, as published data often violate such constraints, jeopardising the value of applications consuming linked data i...
In this paper, we deal with group decision making and propose a model of dialogue among agents that have different knowledge and preferences, but are willing to compromise in order to collaboratively reach a common decision. Agents participating in the dialogue use internal reasoning to resolve conflicts emerging in their knowledge during communica...
Provenance information of digital objects maintained by digital libraries and archives is crucial for authenticity assessment, reproducibility and accountability. Such information is commonly stored on metadata placed in various Metadata Repositories (MRs) or Knowledge Bases (KBs). Nevertheless, in various settings it is prohibitive to store the pr...
When dealing with dynamically evolving datasets, users are often interested in the state of affairs on previous versions of the dataset, and would like to execute queries on such previous versions, as well as queries that compare the state of affairs across different versions. This is especially true for datasets stored in the Web, where the interl...
Reasoning (mainly OWL reasoning) has received increasing attention by ontology designers for more accurately representing the domain at hand. To reflect this importance, one of LDBC’s objectives is to identify a set of interesting use cases that consider OWL reasoning constructs (beyond the usual RDFS constructs) that can be used to challenge exist...
Given the increasing amount of sensitive RDF data available on theWeb, it becomes critical to guarantee secure access to this content. The problem becomes even more di�cult in the presence of RDFS inference
rules. State of the art models for controlling access to RDF data, annotate triples with concrete values that denote whether a triple can be ac...
Reasoning about Action and Change (RAC) and Answer Set Programming (ASP) are two well-known fields in AI for logic-based reasoning. Each paradigm bears unique features and a possible integration can lead to more effective ways to address hard AI problems. In this paper, we report on implementations that embed RAC formalisms and concepts in ASP and...
A novel argumentation semantics of defeasible logic programs (DeLP) is presented. Our goal is to build a semantics, which respects existing semantics and intuitions of "classical" logic programming. Generalized logic programs (GLP) are selected as an appropriate formalism for studying both undermining and rebutting. Our argumentation semantics is b...
The delivery of Public Services to citizens is developing into a challenging task, as the urban population increases and the related networks are becoming more complex and entangled. In this work, we present a GUI application for Smart City Operation Center (SMOC), a platform designed for the optimal coordination of a City's Public Agencies that is...
The operation of contraction (referring to the removal of knowledge from a knowledge base) has been extensively studied in the research field of belief change, and different postulates (e.g., the AGM postulates with recovery, or relevance) have been proposed, as well as several constructions (e.g., partial meet) that allow the definition of contrac...
With the increasing use of Web 2.0 to create, disseminate, and consume large volumes of data, more and more information is published and becomes available for potential data consumers, that is, applications/services, individual users and communities, outside their production site. The most representative example of this trend is Linked Open Data (L...
