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User-Centric resource allocation through a power-efficient jamming-proof RAN on top of a multi-tenant backhaul
No full textThe exponential growth in the number of communicating devices and the increasing demand for better and high-performance communications have made allocation of network resources an issue of extreme importance. The problem is further exacerbated if we consider that, while the number of deployed devices is massive, the amount of network resources is still limited. In this thesis, we aim at providing a holistic approach for resource allocation in modern telecommunication networks. Specifically, we consider a network consisting of a backhaul interconnecting a Radio Access Network (RAN) that provides mobile users with wireless access to a Core Network (CN). The CN allows access to the Internet and enables end-to-end communications by routing users data and calls. We take both energy and security aspects into account, by proposing a power-efficient and jamming-proof resource allocation scheme for the RAN. Furthermore, we consider the
relevant and emerging case where the backhaul is shared among different tenants. Accordingly, we exploit Software Defined Networks (SDNs) and Network Function Virtualization (NFV) paradigms to provide dynamic and flexible network and service management in the
multi-tenant backhaul and CN, respectively. We formulate the resource allocation problem through both centralized and distributed approaches, we discuss the existence and uniqueness of efficient resource allocation solutions and we provide distributed privacy-preserving algorithms that provably converge allow to the optimal resource allocation policy by exploiting only local or shared information
L écriture des émotions : approches cognitives et neuro-esthétiques. Le cas de Boutès de Pascal Quignard
No full textLa mia tesi ha come oggetto di studio la scrittura delle emozioni nell opera di Pascal Quignard, autore francese dell extrême contemporain. In particolare, il mio lavoro si concentra sull analisi degli elementi linguistici e figurativi presenti in Boutès, secondo una prospettiva neuro-cognitiva e neuro-estetica.
Da circa quarant anni, le scienze cognitive si sono interrogate sul ruolo svolto dal nostro sistema cerebrale in tutte le forme di cognizione, quali per esempio la memoria, l elaborazione delle emozioni, l apprendimento e la produzione del linguaggio. All interno di quest ampia area di ricerca, ho individuato tre momenti peculiari per l impulso all analisi del linguaggio delle emozioni: Metaphor We Live By di G. Lakoff e M. Johnson, nel 1980; What is Cognitive Poetics di R. Tsur, nel 1983; e, infine, la capitale scoperta dei neuroni specchio sul finire degli anni Novanta.
La prima parte della tesi è dedicata all esposizione, nell ambito dello studio delle emozioni, delle principali teorie in materia di scienze cognitive e neuroscienze, in particolar modo della poetica e della linguistica cognitiva. La seconda parte è riservata alla presentazione di Pascal Quignard, della sua vita e delle sue opere maggiori, Boutès in primis. La terza parte è invece consacrata all applicazione al testo Boutès delle teorie già esposte nella prima parte e mette in evidenza il ruolo delle metafore concettuali e dei verbi di movimento nell esperienza emotiva dello scrittore e del lettore. Infine, nella quarta parte, analizziamo il ruolo delle immagini e della danza in Boutès, facendo dialogare quest ultimo testo con un altro, Medea. Immagine e danza sono infatti manifestazioni plastiche della scrittura delle emozioni di Quignard, che suggellano il legame da sempre forte in Quignard tra queste due arti e la letteratura e che esaminiamo secondo un approccio neuro-estetico
Electrospun nanofibres for multifunctional composites
No full textElectrospun veils from copolyethersulfones (coPES) were prepared as soluble interlaminar membranes for carbon fiber/epoxy composites. Dissolution trials were carried out to understand the curing cycle. Dry carbon fabrics were covered with electrospun veils and then infused with an unmodified epoxy resin to prepare reinforced laminates. Unreinforced samples with no carbon fabrics were also studied. The coPES9k veils showed full solubility and homogenous morphology. Unreinforced samples, modified by coPES9k veils, showed only minor morphological differences compared to epoxy/coPES blends obtained from coPES9k powder predissolution. The coPES20k veils showed undissolved fibers and inhomogeneous morphologies when blended with an epoxy in the unreinforced samples. Industrial upscaling of the electospinning process was achieved with commercial polyethersulfones provided by Solvay. The veil-toughening concept was demonstrated by increases in the fracture toughness values obtained with respect to unmodified resins. Also nanofilled-fibers were produced and applied as interlaminar toughening veils. The use of nanofibers as carriers for nanofillers was demonstrated by SEM, EDX and TEM analysis
L'introduzione di due nuovi parametri nella diagnostica per immagini dei noduli tiroidei ad incerto potenziale di malignità migliora l'accuratezza diagnostica nell'identificazione delle neoplasie tiroidee.
No full textObiettivo: I noduli tiroidei diagnosticati come proliferazione follicolare (TIR3B) all agobiopsia tiroidea hanno un rilevante rischio di malignità (15-30%), ma il ricorso alla chirurgia risulterà non necessario nella maggior parte dei casi. Il presente studio ha lo scopo di valutare il possibile incremento dell accuratezza diagnostica nel predire la malignità dei noduli tiroidei, grazie all utilizzo di nuovi parametri ecografici ed elastosonografici.
Pazienti e Metodi: Cinquanta pazienti candidati alla chirurgia in quanto affetti da gozzo nodulare diagnosticato come proliferazione follicolare all agobiopsia, sono stati sottoposti ad una valutazione ecografia ed elastosonografica prima dell intervento chirurgico. Abbiamo eseguito specifiche procedure per ridurre la soggettività nell interpretazione dei noduli con struttura eterogenea ed abbiamo aggiunto due nuovi parametri (la vascolarizzazione intra-nodulare irregolare all esame eco-color-Doppler e l estensione extra-nodulare della durezza all elastosonografia). Complessivamente, abbiamo valutato cinque parametri ecografici (ecogenicità, margini irregolari, microcalcificazioni, vascolarizzazione intra-nodulare e la sua irregolarità) e due parametri elastosonografici (la durezza intra-nodulare e la sua estensione al tessuto adiacente). Dopo aver ottenuto la diagnosi istologica, abbiamo determinato l accuratezza diagnostica di ecografia ed elastosonografia separatamente ed in combinazione tra loro.
Risultati: Sensibilità, specificità, valore predittivi positivo (VPP) e negativo (VPN) sono risultati, rispettivamente, 100%, 85%, 63% e 100% per l ecografia tradizionale e 60%, 92,5%, 67% e 90% per l elastosonografia. L introduzione dei due nuovi parametri ha incrementato la sensibilità delle rispettive procedure (dall'80% al 100% per il flusso intra-nodulare irregolare e dal 50% al 60% per l'estensione extra-nodulare della durezza.). Il loro utilizzo nella valutazione combinata di ecografia ed elastosonografia ha migliorato l accuratezza diagnostica in maniera statisticamente significativa: quando 4 o più parametri sui 7 valutati erano presenti, il rischio di malignità è risultato molto elevato (sensibilità 100%, specificità 92.5%, VPP 77% e VPN 100%).
Conclusioni: L introduzione dei due nuovi parametri ecografici ed elastosonografici nella valutazione dei noduli tiroidei diagnosticati TIR3B all agobiopsia ha migliorato in maniera statisticamente significativa l accuratezza diagnostica. L ecografia tradizionale presenta una migliore sensibilità e VPN, mentre l elastosonografia una migliore specificità e VPP. Pertanto è consigliabile un utilizzo combinato delle due metodiche per ottenere dei vantaggi diagnostici
Lactobacillus rhamnosus GG: a versatile probiotic species for foods and human applications
No full textThe research described in this thesis aims to study the versatility of probiotic strains belonging to the Lactobacillus rhamnosus species in order to make renewed probiotic foods and to formulate clinical strategy to restore homeostasis condition in different human ecosystems. To these ends L. rhamnosus H25 strains, belonged to the D3A collection and previously isolated from Pecorino Crotonese cheese, was studied in order to evaluate functional foods feasibility. In addition, to study the usefulness of probiotic administration in human, the ability of L. rhamnosus GG strain to restore vaginal and intestinal ecosystems homeostasis was studie
Selecting Microscopic Equations of State of Nuclear Matter for the study of Neutron Stars
No full textI developed my PhD thesis in the aerea of astronuclear theory, an inter- disciplinary field where many aspects of nuclear physics, particle physics and astrophysics converge. The research carried out is the study of the equation of state of nuclear matter and its implications for the structure of neutron stars. Neutron stars are compact objects produced in the gravitational collapse of very massive stars just after they explode as supernova, and are characterized by central density extremely high, up to one order of magnitude greater than the nuclear saturation density. Therefore the knowledge of the equation of state (EoS) of nuclear matter at high density is critical for the understanding of stellar structure.
During these 3 years, I derived an equation of state for nuclear matter using the many-body microscopic theory by Brueckner-Bethe- Goldstone. The term microscopic comes from the fact that the only ingredient required as input is the nucleon-nucleon interaction, which in the case of nucleons is known from scattering experiments. The in- clusion of nucleonic three-body forces turns out crucial, so that the EoS not only gives the correct values of density and binding energies at the saturation point, but also the correct compressibility and symme- try energy, which all turn out to be compatible with values extracted from phenomenology. The theoretical approach is widely discussed in the Chapter 3. I have systematically explored the different nucleon-nucleon interactions and three body forces (both phenomenological and microscopic ones). With the EoS obtained, I solved the equations of hydrostatic equilibrium of the star, known as Tolman - Oppenheimer - Volkoff equations, and I calculated the stellar configurations for the equilibrium for several EoSs. The calculated maximum masses of neu- tron stars are equal approximately to 2 solar masses, and radii ranging from 12 to 14 km, according to the observational data recently obtained from satellites in X-ray and Gamma of new generation (Chandra, XMM Newton and Integral). The obtained results were published in a Phys- ical Review C [1] and in a proceeding [6]. The results are shown in Chapter 4.
This work has been further extended to the calculation of the ef- fective masses of nucleons, always within the Brueckner theory. This calculation is crucial for the study of neutron star cooling, where one of the main ingredients is the neutrino emissivity, which depends largely on the effective masses of nucleons. I have systematically explored the effective masses with different two- and three-body interactions, and several values of matter asymmetry. This work was published in Phys. Rev, C [2]. Afterwards, the effective masses obtained from the calcu- lation were included in the cooling codes, which are publicly available, along with the stellar cooling gaps of superfluidity, calculated in the same theoretical approach. The results obtained have shown for the first time the important role of the Urca processes in stellar cooling, giving rise to a high flux of neutrinos, and superfluidity in channels 1S0 and 3PF2 of proton and neutron respectively. It is thus explained the cooling of Cassiopeia A, a supernova remnant whose thermal emis- sion has been monitored for many years, and the analysis of which is compatible with the idea that the stellar core is in a superfluid state. The work was published in Monthly Notices of the Royal Astronomical Society (MNRAS) [4] and is discussed in Chapter 5
Analisi numerica di muri in terra rinforzata in campo statico e dinamico
No full textNel lavoro di tesi viene valutato il comportamento in campo statico e dinamico di una determinata tipologia di opere di sostegno con pannelli di facciata in calcestruzzo e rinforzi polimerici. Allo scopo è stata effettuata un analisi numerica con un codice di calcolo agli elementi finiti, definendo quali metodologie tra quelle comunemente utilizzate nella pratica progettuale potrebbero essere più adeguate a verificare la funzionalità e la sicurezza di tali tipologie di opere
A transport beamline solution for laser-driven proton beams: experimental measurements and Monte Carlo simulations
No full textIn the last few decades, ion optical acceleration represented one of the most attractive topics in the relativistic laser-plasma interaction research, opening the possibility to investigate innovative regimes and different potential applications. In particular, it is becoming evident that, in the next future, laser-driven acceleration could represent an effective alternative to conventional particle accelerators. Indeed, laser-matter interaction could lead to more compact and less expensive acceleration systems and, consequently, to a larger availability of high-energy ion beams around the world. Up to now, optically accelerated ion beams are characterised by extreme features, not suitable for many applications and of course also for the hadrontherapy applications, that are the most demanding in terms of beam transport, handling, control and reliability.
Significant effort, at laser/target level as well as by means of customised transport beamlines, is currently ongoing in several facilities world wide in order to demonstrate the possible clinical application of laser-driven beams. Also pre-clinical studies, as the experiment reported in the thesis, were performed to try to improve the knowledge on the biological effectiveness of laser-driven beams in respect to the conventional ones, but in most of cases the uncertainties arising from the beam handling and transport do not allow to achieve undeniable results. Therefore, to reach the required accuracy for radiobiology experiments, it is desirable to better handle and control the transported beam.
According to this requirement, new prototypes for the beam transport and handling have been designed and realised at INFN-LNS in Catania. They can be properly combined in a modular system composing a prototype beamline for the beam collection and energy selection. On the basis of these prototypes, the final transport elements will be realised and assembled within 2017 for the ELIMAIA beamline, at the ELI-Beamlines facility in Prague (Cz).
In addiction to a precise description of the transport beamline prototypes, results from their tests will be reported in the thesis, together with different simulative studies. Monte Carlo simulations have been initially performed to support the design procedure and, at a later stage, to study the particle transport and dose distributions along the beamline. In particular, the Geant4 (GEometry ANd Tracking) Monte Carlo toolkit has been used at this aim.
After the characterisations of each single beamline element with both conventional and laser-driven beams and after the Monte Carlo code validation (performed using the experimental data as reference), the attention was focused on the possibility to study a possible configuration of the whole prototype beamline, properly coupling the two main elements composing that. At this aim, experimental campaigns could be planned for the next months.
To realistically reproduce the configuration to be used in the future experimental campaigns, Monte Carlo simulations of the whole transport beamline prototype were performed and finalised to the realisation of a proof-of-principle radiobiological experiment, that, as will be demonstrate, could be carried out with high dose-rate, small energy spread and well controlled dose distributions.
Summarising, thanks to the experimental and simulative studies reported in this thesis, the control of laser-driven beams with the realised transport beamline prototypes is demonstrated. Even if the obtained results are not sufficient yet for an extended feasibility study related to hadrontherapy applications, they represent an important step towards future and more systematic studies
Urban wastewater reuse in agriculture: recent perspectives from case studies in sicily
No full textThe objective of this study was to monitor and assess environmental impacts of reclaimed wastewater (RW), used for irrigation of vegetable crops, on soil, crop quality and irrigation equipment. During 2013, effluents of a horizontal sub-surface flow constructed treatment wetland (TW) system, used for tertiary treatment of sanitary wastewater from a small rural municipality located in Eastern Sicily (Italy), were reused by micro-irrigation techniques to irrigate vegetable crops. Monitoring programs, based on in situ and laboratory analyses were performed for assessing possible adverse effects on water-soil-plant systems caused by reclaimed wastewater reuse. In particular, experimental results evidenced that Escherichia coli content found in RW would not present a risk for rotavirus infection following WHO (2006) standards. Irrigated soil was characterized by a certain persistence of microbial contamination and among the studied vegetable crops, lettuce responds better, than zucchini and eggplants, to the irrigation with low quality water, evidencing a bettering of nutraceutical properties and production parameters
Gli Archetipi
No full textGli archetipi fino ai primi decenni del 1900 hanno rappresentato per lungo tempo un riferimento certo, una condizione, per le generazioni che si sono succedute, per poter intervenire nel territorio/ambiente. Infatti prima dell avvento del Razionalismo, la metodologia d intervento portava a leggere e a conoscere il luogo prima di progettare e di realizzare. Si usavano pochi materiali naturali, con l uso di regole sicure e consolidate, l architettura esprimeva valori con le forme e le tecniche.
La ricerca si prefigge l obiettivo di riprendere gli archetipi, di analizzarli, comprenderli e riproporli, in modo da tutelare il patrimonio storico-artistico nel contesto regionale, analizzandone la formazione e la diffusione in riferimento al territorio, esaminandone le caratteristiche culturali e tecniche.
Ritornare alla valorizzazione degli archetipi è una meta finalizzata a difendere il patrimonio storico-artistico-culturale del territorio, da cui derivare proposte di intervento.
Detta metodologia porta immediatamente alla riflessione su come vogliamo il paesaggio del domani, ci fa riflettere su come lo volevano e rispettavano gli antenati, come è stato trasformato da chi ha dimenticato per tanti anni il valore del paesaggio.
Riprendere le idee-metodi degli antenati, è un modo per analizzarci e ripercorrere la strada indicata dalle opere realizzate, dopo la desolazione, paesi e città distrutte. Tutto da riesaminare per evitare danneggiamenti, che hanno portato non solo alla cementificazione, all omologazione, ma anche alla distruzione del paesaggio e di tutta la sua memoria amata dai grandi che ci hanno preceduto