1,112 research outputs found
Introduction to ontology engineering
No full textThis chapter provides an introduction to ontology engineering discussing the role of ontologies in informative systems, presenting a methodology for ontology design, and introducing ontology languages. The chapter starts by explaining why ontologies are needed in informative systems, then it introduces the reader to ontologies by leading him/her in a stepwise guide to ontology design. It concludes by introducing ontology languages and standards. This is a primer reading aimed at preparing novice readers of this book to understanding more complex dissertations; for this reason it can be avoided by expert readers
Extracting role hierarchies from authentication data flows
No full textCurrent Web-based applications use XML-based formats to represent user descriptions exchanged between parties of a distributed computation. This paper introduces some techniques for extracting
frequent patterns of user attributes from this XML flow. Then, patterns are used for bottom-up construction of a role ontology,
which is then passed to an ontology engineer for a final pruning.
The result is a user ontology built by combining top-down and bottom-up approaches, supporting extraction and validation of knowledge about "typical" users particularly suitable for fine
grained access control applications
Il ruolo della modulazione del sistema immunitario in seguito alla rottura della placca aterosclerotica durante IMA
No full textL’aterosclerosi, a lungo considerata una patologia essenzialmente legata all’ accumulo di lipidi all’interno della tonaca intima, oggi è riconosciuta come un processo degenerativo infiammatorio cronico ad eziologia multifattoriale che, pur manifestandosi clinicamente nell’adulto, trova prodromi sin dalla giovane età. Il nostro studio, condotto sui pazienti arruolati dopo infarto STEMI e sottoposti a intervento di angioplastica coronarica primaria, è finalizzato a valutare il ruolo della modulazione del sistema immunitario in seguito alla rottura della placca aterosclerotica durante l’infarto. Lo studio ancora in corso, ha evidenziato una presenza massiva dell’ IFN-γ, dell’IL-17 e dell’IL- 21 nelle coronarie affette dalla lesione rispetto a quelle esenti e alle arterie periferiche. Gli elevati livelli di citochine osservati nelle arterie danneggiate non sono dovuti all'aumento del numero delle cellule leucocitarie presenti, ma sono riconducibile all’attivazione cellulare delle stesse e all’espressione del loro pattern citochinico. Nella fase acuta dell’infarto inoltre, i livelli sierici dei fattori proinfiammatori come IL-6 e antiinfiammatori come IL-10 sono aumentati, tuttavia, l'aumento di IL-6 è sensibilmente superiore a quello di IL-10. Dopo un mese dalla lesione i livelli sierici di IL-6 e IL-10 osservati risultano bilanciati. A nostro avviso, l’attivazione prevalente dei fattori proinfiammatori è rilevante nella progressione della lesione e nello sviluppo di complicanze associate all’infarto miocardico acuto.Atherosclerosis, once considered a disease mainly linked to accumulation of lipids within the inner tunic, is now recognized as a chronic inflammatory degenerative process with a multifactorial etiology that, even if occurs clinically in adults, shows prognostic signs at an early age. Our study, performed on patients enrolled after acute myocardial infarction with ST elevation (STEMI) undergoing primary coronary angioplasty, aims to assess the role of the immune system modulation during the atherosclerotic plaque rupture due to myocardial infarction. Preliminary data, showed a massive presence of IFN-γ, IL-17 and IL-21 in coronary arteries affected by lesion compared to those exempt and to peripheral arteries. The high levels of cytokines observed in damaged arteries are not due to the increase in the number of leukocyte cells present, but are due to activation of the same cell and expression of their cytokine pattern. Moreover, in the acute myocardial infarction the serum levels of pro-inflammatory factors such as IL-6 and anti-inflammatory such as IL-10 increased. However, the increase of IL-6 was significantly higher than that of IL-10. After a month of the injury, the observed serum levels of IL-6 and IL-10 are balanced. In our view, the main activity of pro-inflammatory factors is relevant in the progression of the lesion and in the development of complications associated with acute myocardial infarction
Managing identities via interactions between ontologies
No full textIn this paper we describe how an identity management system can be based on user ontologies in order to deal with complex attributes that are needed to model user interests or relationships. The problem of computing efficient bindings between ontology based metadata and XML based standards like SAML is also discussed
Quantify resilience enhancement of UTS through exploiting connected community and internet of everything emerging technologies
No full textThis work aims at investigating and quantifying the Urban Transport System (UTS) resilience enhancement enabled by the adoption of emerging technology such as Internet of Everything (IoE) and the new trend of the Connected Community (CC). A conceptual extension of Functional Resonance Analysis Method (FRAM) and its formalization have been proposed and used to model UTS complexity. The scope is to identify the system functions and their interdependencies with a particular focus on those that have a relation and impact on people and communities. Network analysis techniques have been applied to the FRAM model to identify and estimate the most critical community-related functions. The notion of Variability Rate (VR) has been defined as the amount of output variability generated by an upstream function that can be tolerated/absorbed by a downstream function, without significantly increasing of its subsequent output variability. A fuzzybased quantification of the VR based on expert judgment has been developed when quantitative data are not available. Our approach has been applied to a critical scenario as flash flooding considering two cases: when UTS has CC and IoE implemented or not. However, the method can be applied in different scenarios and critical infrastructures. The results show a remarkable VR enhancement if CC and IoE are deployed
Archivi digitali e valutazione della produzione scientifica
No full textNegli ultimi anni lo sviluppo del World Wide Web ha sostenuto la diffusione di archivi digitali, accessibili via Internet, per materiale bibliografico di vario tipo ma in particolare per i prodotti della ricerca scientifica. Nell’ambito della produzione scientifica la pubblicazione online garantisce un’immediata riduzione dei costi e dei tempi di pubblicazione, nonché dei tempi di accesso e interrogazione degli archivi. Inoltre gli archivi bibliografici online, facilitando l’accesso alle risorse, producono un impatto positivo sul numero di citazioni che una pubblicazione può ottenere; come è stato dimostrato anche empiricamente da alcuni studi [10]. Tuttavia, a ben vedere, questi elementi non esauriscono affatto le innovazioni ai processi di fruizione dei prodotti della ricerca scientifica che l’adozione di archivi digitali può determinare.
Una revisione delle applicazioni del diritto d’autore è ad esempio auspicata dal movimento Open Access [11]. Secondo questo punto di vista l’accesso alle pubblicazioni scientifiche va sempre incentivato in quanto ne beneficiano sia l’autore che la società in generale. Di conseguenza, è sbagliato usare il diritto d’autore come strumento per limitare l’accesso ed andrebbe invece utilizzato per garantire l’accessibilità delle opere. Per realizzare al meglio le potenzialità degli archivi digitali andrebbe quindi ripensato l’intero processo editoriale, derivando profitti non dalla vendita delle opere quanto dall’offerta di spazio agli autori.
Ma un altro valore molto significativo che può essere tratto dall’adozione di archivi digitali è relativo al processo di valutazione dell’impatto della produzione scientifica. Ne sottolinea peraltro l’importanza anche un recente documento della divisione di ricerca della comunità europea intitolato “Assessing Europe’s University based Research” [9]. La valutazione della ricerca è un processo che coinvolge un insieme articolato di attori, quali i centri di ricerca, le università, i governi, le imprese. Gli strumenti di valutazione possono essere di varia natura e riguardare aspetti diversi delle attività di ricerca. Tipicamente un giudizio di valutazione è composto da indicatori che insistono su aspetti differenti. Tuttavia, soprattutto nel settore pubblico, assume particolare rilevanza la valutazione dell’impatto delle pubblicazioni scientifiche prodotte. I temi aperti in questo ambito sono molti. Le iniziative si moltiplicano. L’obiettivo è quello di proporre processi e strumenti in grado di garantire la più elevata correttezza dei dati raccolti e di certificare le informazioni in modo che possano essere utilizzate per procedure di valutazione affidabili. In questo articolo saranno discusse alcune innovazioni che potrebbero essere introdotte negli archivi digitali per migliorare la correttezza dei dati e garantire un processo di certificazione della loro effettività. Dall’analisi emergono alcune linee guida per la realizzazione di un prototipo innovativo che il progetto EPICA, interamente finanziato con i fondi 5 per mille dell’Università degli Studi di Milano, sta implementando, con l’obiettivo di illustrare un tipo di infrastruttura in grado di adattarsi ai processi di interazione attualmente in uso
Special Issue on Knowledge Acquisition Reuse and Evaluation
No full textThe fifth International Workshop on Knowledge Acquisition, Reuse and Evaluation (KARE 2012), held in conjunction with the 8th IEEE international conference on Signal-Image Technology & Internet Based Systems (SITIS 2012), brought together researchers, scientists, engineers, and scholar students to exchange and share their experiences, new ideas, and research results about all aspects of Knowledge, Ontology and Semantic Web Services Engineering. The practical challenges encountered and the solutions adopted were discussed. To improve the quality of the contributions the workshop fostered the discussion during the presentation, giving authors the opportunity to improve their work and extend the presented results. For this reason, authors of accepted papers were invited to submit extended articles to this special issue of the International Journal on Knowledge and Learning. There were 27 submissions and 9 papers were accepted for publication.
This special issue focuses on the theoreticians and practitioners concerned with developing methods and systems that assist the knowledge management process and assessing the suitability of such methods. Thus, the issue includes all aspects of acquiring, modelling and managing knowledge, and their role in the construction of knowledge-based systems. Knowledge acquisition still remains the bottleneck for building a knowledge-based system. Reuse and sharing of knowledge bases are major issues and no satisfactory solutions have been agreed upon yet. There is a wide range of research. Much of the work in this field has been knowledge acquisition. The advent of the age of digital information has brought the problem of knowledge reuse and knowledge evaluation. Our ability to analyse, evaluate and assist the user in reusing knowledge present a great challenge of the next years. A new generation of computational techniques and tools is required to support the acquisition, the reuse and the evaluation of useful knowledge from the rapidly growing volume of information. All of these are to be discussed within this issue.
We gratefully acknowledge the strong research community that gathered around the research problems related to process data analysis and the high quality of their research work, which is hopefully reflected in the papers of this issue. We also would like to express our deep appreciation for the referees’ hard work and dedication. Above all, thanks are due the authors for submitting the best results of their work to this special issue.
We are very grateful to the Università degli Studi di Milano and to University of Technology UTBM for their support
EPICA : easy persistent identifier common architecture
No full textNowadays the World Wide Web has become the most important platform for publishing scientific materials. The first advantages of online publication are instant access and easy, low-cost, distribution and duplication. But of great impact in middle term success of electronic publication is the availability of systems that support citation and metrics to evaluate the performances of the different actors in the scientific sector. EPICA is an new infrastructure technology supporting integration of uniform and persistent naming systems and declarative expression of metrics used to asses performances. This way independent actors are allowed to cooperate in a common infrastructure. The key element to support this integration is the semantic mapping between metrics and scientific publications available in the Web. This paper discusses this vision and proposes preliminary results related to the de nition of a Metrics Assessment Data Model to express this semantic mapping
Testing social network metrics for measuring electoral success in the italian municipal campaign of 2011
No full textIt is often argued that the bias hidden in Social Media data prevent from using them for any statistical inference. In this paper, we investigate the practicability of a new method for predicting electoral outcomes that is less affected by demographics and self-selection bias. In particular, we put in place a first test to understand which social network analysis metrics can exhibit positive correlation with electoral success. Our analysis is not intended to use social media audience as a sample of the whole electorate but just as a sample of the supporters of a candidate. In conclusion, we speculate on the information we can extract measuring the social network of the groups of supporters. Essentially, we get an overview on the variety and extent of the segments of the population represented in these groups, and this probably correlates with the capacity to attract consensus
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