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Clinical characterization of facio-scapulo-humeral muscular dystrophy (FSHD) with short alleles (<20kb)
No full textActMesh- A Cognitive Resource Management paradigm for dynamic mobile Internet Access with Reliability Guarantees
No full textWireless Mesh Networks (WMNs) are going increasing attention as a flexible low-cost networking architecture to provide media Internet access over metropolitan areas to mobile clients requiring multimedia services. In WMNs, Mesh Routers (MRs) from the mesh backbone and accomplish the twofold
task of traffic forwarding, as well as providing multimedia access to mobile Mesh Clients (MCs). Due to the intensive bandwidth-resource requested for supporting QoS-demanding multimedia services, performance of the current WMNs is mainly limited by spectrum-crowding and traffic-congestion, as only scarce spectrum-resources is currently licensed for the MCs' access. In principle, this problem could be mitigated by exploiting in a media-friendly
(e.g., content-aware) way the context-aware capabilities offered by the Cognitive
Radio (CR) paradigm. As integrated exploitation of both content and
context-aware system's capabilities is at the basis of our proposed Active Mesh (ActMesh) networking paradigm. This last aims at defining a network-wide architecture for realizing media-friendly Cognitive Mesh nets (e.g., context aware Cognitive Mesh nets). Hence, main contribution of this work is four fold:
1. After introducing main functional blocks of our ActMesh architecture, suitable self-adaptive Belief Propagation and Soft Data Fusion algorithms are designed to provide context-awareness. This is done under
both cooperative and noncooperative sensing frameworks.
2. The resulting network-wide resource management problem is modelled as a constrained stochastic Network Utility Maximization (NUM) problem, with the dual (contrasting) objective to maximize spectrum efficiency at the network level, while accounting for the perceived quality of the delivered media flows at the client level.
3. A fully distributed, scalable and self-adaptive implementation of the resulting
Active Resource Manager (ARM) is deployed, that explicitly accounts for the energy limits of the battery powered MCs and the effects induced by both fading and client mobility. Due to informationally decentralized architecture of the ActMesh net, the complexity of (possibly, optimal) centralized solutions for resource management becomes prohibitive when number of MCs accessing ActMesh net grow. Furthermore, centralized resource management solutions could required large amounts of time to collect and process the required network information, which, in turn, induce delay that can be unacceptable for delay sensitive media applications, e.g., multimedia streaming. Hence, it is important to develop network-wide ARM policies that are both distributed and scalable by exploiting the radio MCs capabilities to sense, adapt and coordinate themselves.
We validate our analytical models via simulation based numerical tests, that
support actual effectiveness of the overall ActMesh paradigm, both in terms of objective and subjective performance metrics. In particular, the basic tradeoff
among backbone traffic-vs-access traffic arising in the ActMesh net from the bandwidth-efficient opportunistic resource allocation policy pursued by the
deployed ARM is numerically characterized.
The standardization framework we inspire to is the emerging IEEE 802.16h one
Dinamica non lineare fuori del piano di pareti murarie Stato dell'arte, Sperimentazione e Mdellazione
No full textInput-shrinking functions: theory and application
No full textIn this thesis, we contribute to the emerging field of the Leakage-Resilient Cryptography by studying the problem of secure data storage on hardware that may
leak information, introducing a new primitive, a leakage-resilient storage, and showing two different constructions of such storage scheme provably secure against a class of
leakage functions that can depend only on some restricted part of the memory and against a class of computationally weak leakage functions, e.g. functions computable by small circuits,
respectively.
Our results come with instantiations and analysis of concrete parameters.
Furthermore, as second contribution, we present our implementation in C programming language, using the cryptographic library of the OpenSSL project, of a two-party Authenticated Key
Exchange (AKE) protocol, which allows a client and a server, who share a huge secret file, to securely compute a shared key, providing client-to-server authentication, also in the presence of active attackers.
Following the work of Cash et al. (TCC 2007), we based our construction on a Weak Key Exchange (WKE) protocol, developed in the BRM, and a Password-based Authenticated Key
Exchange (PAKE) protocol secure in the Universally Composable (UC) framework.
The WKE protocol showed by Cash et al. uses an explicit construction of averaging sampler, which uses less random bits than the random choice but does not seem to be
efficiently implementable in practice.
In this thesis, we propose a WKE protocol similar but simpler than that one of Cash et al.: our protocol uses more randomness than the Cash et al.'s one, as it simply uses random
choice instead of averaging sampler, but we are able to show an efficient implementation of it.
Moreover, we formally adapt the security analysis of the WKE protocol of Cash et al. to our WKE protocol.
To complete our AKE protocol, we implement the PAKE protocol showed secure in the UC framework by Abdalla et al. (CT-RSA 2008), which is more efficient than the Canetti et al.'s UC-PAKE protocol (EuroCrypt 2005) used in Cash et al.'s work.
In our implementation of the WKE protocol, to achieve small constant communication complexity and amount of randomness, we rely on the Random Oracle (RO) model.
However, we would like to note that in our implementation of the AKE protocol we need also a UC-PAKE protocol which already relies on RO, as it is impossible to achieve UC-PAKE in the
standard model.
In our work we focus not only on the theoretical aspects of the area, providing formal models and proofs, but also on the practical ones, analyzing instantiations, concrete parameters
and implementation of the proposed solutions, to contribute to bridge the gap between theory and practice in this field
CHEMERIN REGULATES NK CELL ACCUMULATION AND ENDOTHELIAL CELL MORPHOGENESIS IN THE DECIDUA DURING EARLY PREGNANCY
No full textDeterminanti di genere nella scelta della carriera: Un'indagine sul sessismo familiare
No full textci si focalizza sullo studio di un particolare fattore che potrebbe influenzare la scelta di un percorso piuttosto che un altro: il sessismo, inteso generalmente come l’insieme di credenze pregiudizievoli basate sul genere della persona. Ci si pone l’obiettivo di verificare se e quanto questo fattore possa essere trasmesso dai genitori e quanto possa influenzare il pensiero dell’adolescente, anche rispetto ai propri interessi e al proprio livello di decisione
La circolazione del libro nella Parma dei Borbone (1749-1805)
No full textLa tesi indaga la circolazione del libro nel ducato di Parma durante la seconda metà del Settecento tra privati possessori, librai e intermediari
MOBILE REMOTE PAYMENT: AN EXPLORATORY STUDY OF MERCHANT ADOPTION
No full textThere are more than 5.6 billion mobile phone users worldwide, making mobile phones more common than PCs. Mobile technology is a modern phenomenon with a great impact on industries and our society. Mobile phones began as very limited devices that provided only voice services. Today, these devices also provide a myriad of data services that allow us to browse the Internet, send text messages, check emails, watch movies, listen to music, take pictures, record videos, play video games and read documents.
Mobile can also be used for payments, thus adopted by merchants in such a way to provide a new way for their customers to make their purchases.
Different systems and business models have been developed for enabling Mobile Payments such as "Proximity" systems based on NFC technology and "Remote" systems that use the Mobile Operator's network and mostly widely adopted technologies such as SMS, WAP and Mobile Internet. Mobile remote payment systems are one of the most popular technologies for transactions today, especially across the media and online industries.
Prior research mostly focuses on technology innovation or consumer-centric view while there is still less knowledge related to supply-side perspective and merchant attitude towards adoption of Mobile Payments. Literature is even more scarce when it comes to understanding the merchant adoption of specific Mobile Payment Systems such as "Remote Payment" systems based on carrier billing technologies. Typically, these systems have been widely adopted by merchants around the world and for some have become a phenomenal tool of success. There is also scarcity of research describing the operative factors affecting the deployment and management of Mobile Payments.
This research is an exploratory research of the merchant adoption of Carrier Billed Mobile Remote Payments. This qualitative study was based on in depth interviews conducted on executives and managers from 15 international companies that operate globally in the digital space and that have made a successful use of Mobile Remote Payments.
The results of this research are divided into two parts. In the first one, which is dedicated to the "Strategic Phase", the research aims to understand what enables, drives and inhibits the adoption of Mobile Remote Payment systems by merchants. In the second part, the “Operative Phase”, the research instead outlines the factors driving or inhibiting the successful deployment and management of such systems by merchants. Both parts are organized into descriptive frameworks where the factors identified are analyzed in great detail and explained also through direct quotes of the interviewees.
What emerges from the “Strategic” part of this study is that in order for merchants to adopt Mobile Remote Payments, they must operate within very strict limitations, such as offering mainly digital goods and services and within a micro-transaction based business model. Furthermore, these merchants have to bear incredibly high commissions if compared to credit card or other payment tools. However it emerges that this tool is so simple and secure to use, and immediately available to anybody with a mobile phone that it produces key beneficial factors for the merchants that really drive their adoption. These factors include addressing unbanked users (Young people, emerging markets), increasing impulse purchases and the possibility of developing new business models.
The result of the study of the operative phase shows that 4 macro factors clearly need to be considered when merchants deploy and manage a Mobile Remote Payment system. These are 1) Purchase Experience; 2) Payment System Reputation; 3) Merchant – Provider Relationship; 4) Price Structure and Billing Policies
Machiavelli's Republic: On Some Enduring Principles of the Discourses on Livy
No full textMachiavelli, though best known as a teacher of princes, is also a teacher of republics. He is the author not only of the Principe but also of the Discorsi sopra la prima deca di Tito Livio, a work which is not less fundamental to his thought, and which gives explicit instructions for the ordering of a free society. The aim of this thesis is to explain those instructions and to indicate their relevance today. In this respect, the thesis follows the trail blazed in recent decades by Quentin Skinner and his associates, who have argued that Machiavelli’s conception of liberty, after five centuries, remains useful. But the thesis finds that Skinner's understanding of Machiavelli is both incomplete and, on some crucial points, inaccurate
