23 research outputs found
Convergenze semantiche tra musei, archivi e biblioteche. Ontologie per le relazioni interpersonali
This paper presents the state of the art of the cataloguing description of personal relationships between creators of archival records and people that are related to the life cycle of cultural objects, as highlighted by museums, archives and libraries records (i.e. GLAM, translated in italian MAB). Since people are fundamental access points to the cultural heritage, the representation of relationships between people and corporate bodies in Linked Open Data is of increasing interest. Nonetheless, a shared and comprehensive vocabulary of personal relationships is not available yet. Leveraging on Semantic Web technologies, and ontologies in particular, the aim is to identify existing ontologies that allow to represent relationships in their context (i.e. time, space and events); to map and classify different types of personal relationships; and to provide a formal representation of relationships not available in existing ontologies. As a result, we present an ontology, with a controlled vocabulary, for the representation of the scenario of personal relationships in the cultural heritage domain
Pattern-based design applied to cultural heritage knowledge graphs
Ontology Design Patterns (ODPs) have become an established and recognised
practice for guaranteeing good quality ontology engineering. There are several
ODP repositories where ODPs are shared as well as ontology design methodologies
recommending their reuse. Performing rigorous testing is recommended as well
for supporting ontology maintenance and validating the resulting resource
against its motivating requirements. Nevertheless, it is less than
straightforward to find guidelines on how to apply such methodologies for
developing domain-specific knowledge graphs. ArCo is the knowledge graph of
Italian Cultural Heritage and has been developed by using eXtreme Design (XD),
an ODP- and test-driven methodology. During its development, XD has been
adapted to the need of the CH domain e.g. gathering requirements from an open,
diverse community of consumers, a new ODP has been defined and many have been
specialised to address specific CH requirements. This paper presents ArCo and
describes how to apply XD to the development and validation of a CH knowledge
graph, also detailing the (intellectual) process implemented for matching the
encountered modelling problems to ODPs. Relevant contributions also include a
novel web tool for supporting unit-testing of knowledge graphs, a rigorous
evaluation of ArCo, and a discussion of methodological lessons learned during
ArCo development
The Landscape of Ontology Reuse Approaches
Ontology reuse aims to foster interoperability and facilitate knowledge
reuse. Several approaches are typically evaluated by ontology engineers when
bootstrapping a new project. However, current practices are often motivated by
subjective, case-by-case decisions, which hamper the definition of a
recommended behaviour. In this chapter we argue that to date there are no
effective solutions for supporting developers' decision-making process when
deciding on an ontology reuse strategy. The objective is twofold: (i) to survey
current approaches to ontology reuse, presenting motivations, strategies,
benefits and limits, and (ii) to analyse two representative approaches and
discuss their merits
Semantic Integration of MIR Datasets with the Polifonia Ontology Network
Integration between different data formats, and between data belonging to different collections, is an ongoing challenge in the MIR field. Semantic Web tools have proved to be promising resources for making different types of music information interoperable. However, the use of these technologies has so far been limited and scattered in the field. To address this, the Polifonia project is developing an ontological ecosystem that can cover a wide variety of musical aspects (musical features, instruments, emotions, performances). In this paper, we present the Polifonia Ontology Network, an ecosystem that enables and fosters the transition towards semantic MIR
Knowledge Graphs Evolution and Preservation -- A Technical Report from ISWS 2019
One of the grand challenges discussed during the Dagstuhl Seminar "Knowledge
Graphs: New Directions for Knowledge Representation on the Semantic Web" and
described in its report is that of a: "Public FAIR Knowledge Graph of
Everything: We increasingly see the creation of knowledge graphs that capture
information about the entirety of a class of entities. [...] This grand
challenge extends this further by asking if we can create a knowledge graph of
"everything" ranging from common sense concepts to location based entities.
This knowledge graph should be "open to the public" in a FAIR manner
democratizing this mass amount of knowledge." Although linked open data (LOD)
is one knowledge graph, it is the closest realisation (and probably the only
one) to a public FAIR Knowledge Graph (KG) of everything. Surely, LOD provides
a unique testbed for experimenting and evaluating research hypotheses on open
and FAIR KG. One of the most neglected FAIR issues about KGs is their ongoing
evolution and long term preservation. We want to investigate this problem, that
is to understand what preserving and supporting the evolution of KGs means and
how these problems can be addressed. Clearly, the problem can be approached
from different perspectives and may require the development of different
approaches, including new theories, ontologies, metrics, strategies,
procedures, etc. This document reports a collaborative effort performed by 9
teams of students, each guided by a senior researcher as their mentor,
attending the International Semantic Web Research School (ISWS 2019). Each team
provides a different perspective to the problem of knowledge graph evolution
substantiated by a set of research questions as the main subject of their
investigation. In addition, they provide their working definition for KG
preservation and evolution
Fatality rate and predictors of mortality in an Italian cohort of hospitalized COVID-19 patients
Clinical features and natural history of coronavirus disease 2019 (COVID-19) differ widely among different countries and during different phases of the pandemia. Here, we aimed to evaluate the case fatality rate (CFR) and to identify predictors of mortality in a cohort of COVID-19 patients admitted to three hospitals of Northern Italy between March 1 and April 28, 2020. All these patients had a confirmed diagnosis of SARS-CoV-2 infection by molecular methods. During the study period 504/1697 patients died; thus, overall CFR was 29.7%. We looked for predictors of mortality in a subgroup of 486 patients (239 males, 59%; median age 71 years) for whom sufficient clinical data were available at data cut-off. Among the demographic and clinical variables considered, age, a diagnosis of cancer, obesity and current smoking independently predicted mortality. When laboratory data were added to the model in a further subgroup of patients, age, the diagnosis of cancer, and the baseline PaO2/FiO2 ratio were identified as independent predictors of mortality. In conclusion, the CFR of hospitalized patients in Northern Italy during the ascending phase of the COVID-19 pandemic approached 30%. The identification of mortality predictors might contribute to better stratification of individual patient risk
Empirical ontology design patterns
Knowledge graphs (KGs) and ontologies have been widely adopted for modelling numerous domains.
However, understanding the content of an ontology/KG is far from straightforward: existing methods partially address this issue.
This thesis is based on the assumption that identifying the Ontology Design Patterns (ODPs) in an ontology or a KG contributes to address this problem.
Most times, the reused ODPs are not explicitly annotated, or their reuse is unintentional.
Therefore, there is a challenge to automatically identify ODPs in existing ontologies and KGs, which is the main focus of this research work.
This thesis analyses the role of ODPs in ontology engineering, through experiences in actual ontology projects, placing this analysis in the context of existing ontology reuse approaches.
Moreover, this thesis introduces a novel method for extracting empirical ODPs (EODPs) from ontologies, and a novel method for extracting EODPs from knowledge graphs, whose schemas are implicit.
The first method groups the extracted EODPs in clusters: conceptual components. Each conceptual component represents a modelling problem, e.g. representing collections.
As EODPs are fragments possibly extracted from different ontologies, some of them will fall in the same cluster, meaning that they are implemented solutions to the same modelling problem.
EODPs and conceptual components enable the empirical observation and comparison of modelling solutions to common modelling problems in different ontologies.
The second method extracts EODPs from a KG as sets of probabilistic axioms/constraints involving the ontological entities instantiated.
These EODPs may support KG inspection and comparison, providing insights on how certain entities are described in a KG.
An additional contribution of this thesis is an ontology for annotating ODPs in ontologies and KGs
Extraction of common conceptual components from multiple ontologies
Understanding large ontologies is still an issue, and has an impact on many
ontology engineering tasks. We describe a novel method for identifying and
extracting conceptual components from domain ontologies, which are used to
understand and compare them. The method is applied to two corpora of ontologies
in the Cultural Heritage and Conference domain, respectively. The results,
which show good quality, are evaluated by manual inspection and by correlation
with datasets and tool performance from the ontology alignment evaluation
initiative
Convergenze semantiche tra musei, archivi e biblioteche. Ontologie per le relazioni interpersonali
This paper presents the state of the art of the cataloguing description of personal relationships between creators of archival records and people that are related to the life cycle of cultural objects, as highlighted by museums, archives and libraries records (i.e. GLAM, translated in italian MAB). Since people are fundamental access points to the cultural heritage, the representation of relationships between people and corporate bodies in Linked Open Data is of increasing interest. Nonetheless, a shared and comprehensive vocabulary of personal relationships is not available yet. Leveraging on Semantic Web technologies, and ontologies in particular, the aim is to identify existing ontologies that allow to represent relationships in their context (i.e. time, space and events); to map and classify different types of personal relationships; and to provide a formal representation of relationships not available in existing ontologies. As a result, we present an ontology, with a controlled vocabulary, for the representation of the scenario of personal relationships in the cultural heritage domain.Il presente contributo intende analizzare lo stato dell’arte nella descrizione delle relazioni interpersonali tra soggetti produttori d’archivio e figure legate al ciclo di vita di oggetti culturali - nell’ambito museale, archivistico e bibliotecario (MAB). In quanto punti di accesso fondamentali al patrimonio culturale, la rappresentazione delle relazioni tra persone e organizzazioni è oggetto di crescente interesse nella produzione di Linked Open Data. Nonostante ciò, non esiste al momento un vocabolario condiviso che fornisca una visuale esaustiva sulle relazioni interpersonali che caratterizzano il dominio MAB. Utilizzando la lente delle tecnologie del Semantic Web, e delle ontologie in particolare, l’obiettivo è identificare le ontologie esistenti che permettono di esprimere aspetti temporali, spaziali ed evenemenziali delle relazioni; mappare e classificare le tipologie di relazioni interpersonali; fornire una rappresentazione formale di quelle che non siano disponibili in ontologie esistenti. Il risultato è una ontologia, comprensiva di un vocabolario controllato di termini, per la rappresentazione dello scenario delle relazioni interpersonali nel dominio dei beni culturali