People semantic description and re-identification from point cloud geometry

The automatic extraction of biometric descriptors of anonymous people is a challenging scenario in camera networks. This task is typically accomplished making use of visual information. Calibrated RGBD sensors make possible the extraction of point cloud information. We present a novel approach for people semantic description and re-identification using the individual point cloud information. The proposal combines the use of simple geometric features with point cloud features based on surface normals.

Semantic-based middleware solutions to support context-aware service provisioning in pervasive environments

The dynamicity and heterogeneity that characterize pervasive environments raise new challenges in the design of mobile middleware. Pervasive environments are characterized by a significant degree of heterogeneity, variability, and dynamicity that conventional middleware solutions are not able to adequately manage. Originally designed for use in a relatively static context, such middleware systems tend to hide low-level details to provide applications with a transparent view on the underlying execution platform. In mobile environments, however, the context is extremely dynamic and cannot be managed by a priori assumptions. Novel middleware should therefore support mobile computing applications in the task of adapting their behavior to frequent changes in the execution context, that is, it should become context-aware. In particular, this thesis has identified the following key requirements for novel context-aware middleware that existing solutions do not fulfil yet. (i) Middleware solutions should support interoperability between possibly unknown entities by providing expressive representation models that allow to describe interacting entities, their operating conditions and the surrounding world, i.e., their context, according to an unambiguous semantics. (ii) Middleware solutions should support distributed applications in the task of reconfiguring and adapting their behavior/results to ongoing context changes. (iii) Context-aware middleware support should be deployed on heterogeneous devices under variable operating conditions, such as different user needs, application requirements, available connectivity and device computational capabilities, as well as changing environmental conditions. Our main claim is that the adoption of semantic metadata to represent context information and context-dependent adaptation strategies allows to build context-aware middleware suitable for all dynamically available portable devices. Semantic metadata provide powerful knowledge representation means to model even complex context information, and allow to perform automated reasoning to infer additional and/or more complex knowledge from available context data. In addition, we suggest that, by adopting proper configuration and deployment strategies, semantic support features can be provided to differentiated users and devices according to their specific needs and current context. This thesis has investigated novel design guidelines and implementation options for semantic-based context-aware middleware solutions targeted to pervasive environments. These guidelines have been applied to different application areas within pervasive computing that would particularly benefit from the exploitation of context. Common to all applications is the key role of context in enabling mobile users to personalize applications based on their needs and current situation. The main contributions of this thesis are (i) the definition of a metadata model to represent and reason about context, (ii) the definition of a model for the design and development of context-aware middleware based on semantic metadata, (iii) the design of three novel middleware architectures and the development of a prototypal implementation for each of these architectures, and (iv) the proposal of a viable approach to portability issues raised by the adoption of semantic support services in pervasive applications.

Semantic coordination tuple centres for eHealth Systems

In questa tesi partendo dai limiti sintattici dello scambio di Electronic Patient Records (EHRs), si arriva alla creazione di un framework che supporti lo scambio di informazioni semantiche. Il framework creato si chiama Semantic TuCSoN ed è una estensione di TuCSoN (Tuple Centres Spread over the Network). Semantic TuCSoN viene modellato per il contesto eHealth definendo gli agenti e le politiche di coordinamento atte allo scambio di EHR. Questo framework vine infine testa per verificarne le performance allo scopo di valutare un suo ulteriore utilizzo.

Supporting semantic web technologies in the pervasive service ecosystems middleware

Semantic Web technologies are strategic in order to fulfill the openness requirement of Self-Aware Pervasive Service Ecosystems. In fact they provide agents with the ability to cope with distributed data, using RDF to represent information, ontologies to describe relations between concepts from any domain (e.g. equivalence, specialization/extension, and so on) and reasoners to extract implicit knowledge. The aim of this thesis is to study these technologies and design an extension of a pervasive service ecosystems middleware capable of exploiting semantic power, and deepening performance implications.

A novel map-matching procedure for low-sampling GPS data with applications to traffic flow analysis

An extensive sample (2%) of private vehicles in Italy are equipped with a GPS device that periodically measures their position and dynamical state for insurance purposes. Having access to this type of data allows to develop theoretical and practical applications of great interest: the real-time reconstruction of traffic state in a certain region, the development of accurate models of vehicle dynamics, the study of the cognitive dynamics of drivers. In order for these applications to be possible, we first need to develop the ability to reconstruct the paths taken by vehicles on the road network from the raw GPS data. In fact, these data are affected by positioning errors and they are often very distanced from each other (~2 Km). For these reasons, the task of path identification is not straightforward. This thesis describes the approach we followed to reliably identify vehicle paths from this kind of low-sampling data. The problem of matching data with roads is solved with a bayesian approach of maximum likelihood. While the identification of the path taken between two consecutive GPS measures is performed with a specifically developed optimal routing algorithm, based on A* algorithm. The procedure was applied on an off-line urban data sample and proved to be robust and accurate. Future developments will extend the procedure to real-time execution and nation-wide coverage.

Semantic Enrichment of Scientific Documents with Semantic Lenses – Developing methodologies, tools and prototypes for their concrete use

Con questa dissertazione di tesi miro ad illustrare i risultati della mia ricerca nel campo del Semantic Publishing, consistenti nello sviluppo di un insieme di metodologie, strumenti e prototipi, uniti allo studio di un caso d‟uso concreto, finalizzati all‟applicazione ed alla focalizzazione di Lenti Semantiche (Semantic Lenses).

Conversione per il Semantic Web di dati Turistico-Culturali: il progetto QRPlaces - Semantic Events

Il progetto QRPlaces - Semantic Events, oggetto di questo lavoro, focalizza l’attenzione sull’analisi, la progettazione e l’implementazione di un sistema che sia in grado di modellare i dati, relativi a diversi eventi facenti parte del patrimonio turistico - culturale della Regione Emilia Romagna 1, rendendo evidenti i vantaggi associati ad una rappresentazione formale incentrata sulla Semantica. I dati turistico - culturali sono intesi in questo ambito sia come una rappresentazione di “qualcosa che accade in un certo punto ad un certo momento” (come ad esempio un concerto, una sagra, una raccolta fondi, una rappresentazione teatrale e quant’altro) sia come tradizioni e costumi che costituiscono il patrimonio turistico-culturale e a cui si fa spesso riferimento con il nome di “Cultural Heritage”. Essi hanno la caratteristica intrinseca di richiedere una conoscenza completa di diverse informa- zioni correlata, come informazioni di geo localizzazione relative al luogo fisico che ospita l’evento, dati biografici riferiti all’autore o al soggetto che è presente nell’evento piuttosto che riferirsi ad informazioni che descrivono nel dettaglio tutti gli oggetti, come teatri, cinema, compagnie teatrali che caratterizzano l’evento stesso. Una corretta rappresentazione della conoscenza ad essi legata richiede, pertanto, una modellazione in cui i dati possano essere interconnessi, rivelando un valore informativo che altrimenti resterebbe nascosto. Il lavoro svolto ha avuto lo scopo di realizzare un dataset rispondente alle caratteristiche tipiche del Semantic Web grazie al quale è stato possibile potenziare il circuito di comunicazione e informazione turistica QRPlaces 2. Nello specifico, attraverso la conversione ontologica di dati di vario genere relativi ad eventi dislocati nel territorio, e sfruttando i principi e le tecnologie del Linked Data, si è cercato di ottenere un modello informativo quanto più possibile correlato e arricchito da dati esterni. L’obiettivo finale è stato quello di ottenere una sorgente informativa di dati interconnessi non solo tra loro ma anche con quelli presenti in sorgenti esterne, dando vita ad un percorso di collegamenti in grado di evidenziare una ricchezza informativa utilizzabile per la creazione di valore aggiunto che altrimenti non sarebbe possibile ottenere. Questo aspetto è stato realizzato attraverso un’in- terfaccia di MashUp che utilizza come sorgente il dataset creato e tutti i collegamenti con la rete del Linked Data, in grado di reperire informazioni aggiuntive multi dominio.

Semantic Publishing: issues, solutions and new trends in scholarly publishing within the Semantic Web era

This work is concerned with the increasing relationships between two distinct multidisciplinary research fields, Semantic Web technologies and scholarly publishing, that in this context converge into one precise research topic: Semantic Publishing. In the spirit of the original aim of Semantic Publishing, i.e. the improvement of scientific communication by means of semantic technologies, this thesis proposes theories, formalisms and applications for opening up semantic publishing to an effective interaction between scholarly documents (e.g., journal articles) and their related semantic and formal descriptions. In fact, the main aim of this work is to increase the users' comprehension of documents and to allow document enrichment, discovery and linkage to document-related resources and contexts, such as other articles and raw scientific data. In order to achieve these goals, this thesis investigates and proposes solutions for three of the main issues that semantic publishing promises to address, namely: the need of tools for linking document text to a formal representation of its meaning, the lack of complete metadata schemas for describing documents according to the publishing vocabulary, and absence of effective user interfaces for easily acting on semantic publishing models and theories.

Semantic Service Architectures for Smart Environments

Many industries and academic institutions share the vision that an appropriate use of information originated from the environment may add value to services in multiple domains and may help humans in dealing with the growing information overload which often seems to jeopardize our life. It is also clear that information sharing and mutual understanding between software agents may impact complex processes where many actors (humans and machines) are involved, leading to relevant socioeconomic benefits. Starting from these two input, architectural and technological solutions to enable “environment-related cooperative digital services” are here explored. The proposed analysis starts from the consideration that our environment is physical space and here diversity is a major value. On the other side diversity is detrimental to common technological solutions, and it is an obstacle to mutual understanding. An appropriate environment abstraction and a shared information model are needed to provide the required levels of interoperability in our heterogeneous habitat. This thesis reviews several approaches to support environment related applications and intends to demonstrate that smart-space-based, ontology-driven, information-sharing platforms may become a flexible and powerful solution to support interoperable services in virtually any domain and even in cross-domain scenarios. It also shows that semantic technologies can be fruitfully applied not only to represent application domain knowledge. For example semantic modeling of Human-Computer Interaction may support interaction interoperability and transformation of interaction primitives into actions, and the thesis shows how smart-space-based platforms driven by an interaction ontology may enable natural ad flexible ways of accessing resources and services, e.g, with gestures. An ontology for computational flow execution has also been built to represent abstract computation, with the goal of exploring new ways of scheduling computation flows with smart-space-based semantic platforms.

Semantic under-determinacy, Content and Context

The aim of the thesis is to investigate the topic of semantic under-determinacy, i.e. the failure of the semantic content of certain expressions to determine a truth-evaluable utterance content. In the first part of the thesis, I engage with the problem of setting apart semantic under-determinacy as opposed to other phenomena such as ambiguity, vagueness, indexicality. As I will argue, the feature that distinguishes semantic under-determinacy from these phenomena is its being explainable solely in terms of under-articulation. In the second part of the thesis, I discuss the topic of how communication is possible, despite the semantic under-determinacy of language. I discuss a number of answers that have been offered: (i) the Radical Contextualist explanation which emphasises the role of pragmatic processes in utterance comprehension; (ii) the Indexicalist explanation in terms of hidden syntactic positions; (iii) the Relativist account, which regards sentences as true or false relative to extra coordinates in the circumstances of evaluation (besides possible worlds). In the final chapter, I propose an account of the comprehension of utterances of semantically under-determined sentences in terms of conceptual constraints, i.e. ways of organising information which regulate thought and discourse on certain matters. Conceptual constraints help the hearer to work out the truth-conditions of an utterance of a semantically under-determined sentence. Their role is clearly semantic, in that they contribute to “what is said” (rather than to “what is implied”); however, they do not respond to any syntactic constraint. The view I propose therefore differs, on the one hand, from Radical Contextualism, because it stresses the role of semantic-governed processes as opposed to pragmatics-governed processes; on the other hand, it differs from Indexicalism in its not endorsing any commitment as to hidden syntactic positions; and it differs from Relativism in that it maintains a monadic notion if truth.

On the path of Exploratory Search Users - A Semantic Web tool

L’Exploratory Search, paradigma di ricerca basato sulle attività di scoperta e d’apprendimento, è stato per diverso tempo ignorato dai motori di ricerca tradizionali. Invece, è spesso dalle ricerche esplorative che nascono le idee più innovative. Le recenti tecnologie del Semantic Web forniscono le soluzioni che permettono d’implementare dei motori di ricerca capaci di accompagnare gli utenti impegnati in tale tipo di ricerca. Aemoo, motore di ricerca sul quale s’appoggia questa tesi ne è un esempio efficace. A partire da quest’ultimo e sempre con l’aiuto delle tecnologie del Web of Data, questo lavoro si propone di fornire una metodologia che permette di prendere in considerazione la singolarità del profilo di ciascun utente al fine di guidarlo nella sua ricerca esplorativa in modo personalizzato. Il criterio di personalizzazione che abbiamo scelto è comportamentale, ovvero basato sulle decisioni che l’utente prende ad ogni tappa che ritma il processo di ricerca. Implementando un prototipo, abbiamo potuto testare la validità di quest’approccio permettendo quindi all’utente di non essere più solo nel lungo e tortuoso cammino che porta alla conoscenza.

Linked Data e bibliometriche: un indice di multidisciplinarieta nel Semantic Publishing

Nel presente lavoro si introduce un nuovo indice per la valutazione dei prodotti della ricerca: l'indice di multidisciplinarieta`. Questa nuova metrica puo` essere un interessante parametro di valutazione: il panorama degli studi multidisciplinari e` vasto ed eterogeneo, ed all'interno di questo sono richieste necessarie competenze trasversali. Le attuali metriche adottate nella valutazione di un accademico, di un journal, o di una conferenza non tengono conto di queste situazioni intermedie, e limitano la loro valutazione dell'impatto al semplice conteggio delle citazioni ricevute. Il risultato di tale valutazione consiste in un valore dell'impatto della ricerca senza una connotazione della direzione e della rilevanza di questa nel contesto delle altre discipline. L'indice di multidisciplinarieta` proposto si integrerebbe allora all'interno dell'attuale panorama delle metriche di valutazione della ricerca, offrendo -accanto ad una quantificazione dell'impatto- una quantificazione della varieta` dei contesti disciplinari nei quali si inserisce.