The twofold role of Cloud Computing in Digital Forensics: target of investigations and helping hand to evidence analysis

This PhD thesis discusses the impact of Cloud Computing infrastructures on Digital Forensics in the twofold role of target of investigations and as a helping hand to investigators. The Cloud offers a cheap and almost limitless computing power and storage space for data which can be leveraged to commit either new or old crimes and host related traces. Conversely, the Cloud can help forensic examiners to find clues better and earlier than traditional analysis applications, thanks to its dramatically improved evidence processing capabilities. In both cases, a new arsenal of software tools needs to be made available. The development of this novel weaponry and its technical and legal implications from the point of view of repeatability of technical assessments is discussed throughout the following pages and constitutes the unprecedented contribution of this work

La crittografia nel sistema di moneta digitale Bitcoin

In questo documento si presenta lo studio degli algoritmi matematici e crittografici su cui si basa il sistema di moneta digitale Bitcoin, in circolazione dal 2009. Bitcoin è un sistema di cripto valuta elettronica peer-to-peer, ideato da un anonimo conosciuto con lo pseudonimo "Satoshi Nakamoto", i cui principi sono descritti in un documento pubblicato nel 2008 ed ora accessibile in rete. L'utilizzo di Bitcoin permette di effettuare transazioni con sicurezza da un soggetto ad un altro e, grazie a una tecnologia peer-to-peer che opera senza alcuna autorità centrale e intermediari quali banche o istituzioni governative, sia la gestione delle operazioni sia l'emissione di denaro sono svolte per mezzo di un protocollo P2P. Nel corso della trattazione si propone un analisi più tecnica del sistema di gestione e creazione dei Bitcoin e degli strumenti crittografici che hanno permesso l'avvento di questa moneta elettronica decentralizzata.

Connectivity management and dynamic context grouping in mobile heterogenous systems

In the last 10 years the number of mobile devices has grown rapidly. Each person usually brings at least two personal devices and researchers says that in a near future this number could raise up to ten devices per person. Moreover, all the devices are becoming more integrated to our life than in the past, therefore the amount of data exchanged increases accordingly to the improvement of people's lifestyle. This is what researchers call Internet of Things. Thus, in the future there will be more than 60 billions of nodes and the current infrastructure is not ready to keep track of all the exchanges of data between them. Therefore, infrastructure improvements have been proposed in the last years, like MobileIP and HIP in order to facilitate the exchange of packets in mobility, however none of them have been optimized for the purpose. In the last years, researchers from Mid Sweden University created The MediaSense Framework. Initially, this framework was based on the Chord protocol in order to route packets in a big network, but the most important change has been the introduction of PGrids in order to create the Overlay and the persistence. Thanks to this technology, a lookup in the trie takes up to 0.5*log(N), where N is the total number of nodes in the network. This result could be improved by further optimizations on the management of the nodes, for example by the dynamic creation of groups of nodes. Moreover, since the nodes move, an underlaying support for connectivity management is needed. SCTP has been selected as one of the most promising upcoming standards for simultaneous multiple connection's management.

Introduction to Reservoir Computing Methods

Il documento tratta la famiglia di metodologie di allenamento e sfruttamento delle reti neurali ricorrenti nota sotto il nome di Reservoir Computing. Viene affrontata un'introduzione sul Machine Learning in generale per fornire tutti gli strumenti necessari a comprendere l'argomento. Successivamente, vengono dati dettagli implementativi ed analisi dei vantaggi e punti deboli dei vari approcci, il tutto con supporto di codice ed immagini esplicative. Nel finale vengono tratte conclusioni sugli approcci, su quanto migliorabile e sulle applicazioni pratiche.

Scalable and Seamless Discovery and Selection of Services in Mobile Cloud Computing

Mobile devices are now capable of supporting a wide range of applications, many of which demand an ever increasing computational power. To this end, mobile cloud computing (MCC) has been proposed to address the limited computation power, memory, storage, and energy of such devices. An important challenge in MCC is to guarantee seamless discovery of services. To this end, this thesis proposes an architecture that provides user-transparent and low-latency service discovery, as well as automated service selection. Experimental results on a real cloud computing testbed demonstrated that the proposed work outperforms state of-the-art approaches by achieving extremely low discovery delay.

Sviluppo di sistemi mobile ad alta densita basati su comunicazioni opportunistiche wireless

In questa tesi ci si pone l'obiettivo di sviluppare sistemi distribuiti composti da device mobile che si scambiano informazioni tramite comunicazioni opportunistiche wireless peer-to-peer. Vengono inizialmente analizzate le principali tecnologie di comunicazione wireless adatte allo scopo, soffermandosi sulle reti Wifi ad hoc, delle quali vengono studiate le performance in sistemi di larga scala tramite il simulatore di reti ns-3. Successivamente viene esposto lo sviluppo di componenti software, basati su Akka Stream, per la costruzione di campi computazionali tramite comunicazioni opportunistiche tra device Android, effettuate tramite reti Wifi ad hoc.

How does socio economic position link to health behaviour? Sociological pathways and perspectives for health promotion

Socio economic inequalities in adult health behaviour are consistently observed. Despite a well-documented pattern, social determinants of variations in health behaviour have not been sufficiently clarified. This article therefore presents sociological pathways to explain the existing inequalities in health behaviour. At a micro level, control beliefs have been part of several behavioural theories. We suggest that these beliefs might bridge the gap between sociology and psychology by emphasising their roots in fundamental socio-economic environments. At a meso level, social networks and support have not been explicitly considered as behavioural determinants. This contribution states that these social factors influence health behaviour while being unequally distributed across society. At a macro level, characteristics of the neighbourhood environment influence health behaviour of its residents above and beyond their individual background. Providing further opportunity for policy makers, it is shown that peer and school context equalise inequalities in risky behaviour in adolescence. As a conclusion, factors such as control expectations, social networks, neighbourhood characteristics, and school context should be included as strategies to improve health behaviour in socially disadvantaged people.

Predictors of surgical, general and follow-up complications in lumbar spinal stenosis relative to patient age as emerged from the Spine Tango Registry

Published opinions regarding the outcomes and complications in older patients have a broad spectrum and there is a disagreement whether surgery in older patients entails a higher risk. Therefore this study examines the risk of surgery for lumbar spinal stenosis relative to age in the pooled data set of the Spine Tango registry.