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Application of Deep Learning techniques in the search for BSM Higgs bosons in the final state in CMS
Get PDFThe Standard Model (SM) of particle physics predicts the existence of a Higgs field responsible for the generation of particles' mass. However, some aspects of this theory remain unsolved, supposing the presence of new physics Beyond the Standard Model (BSM) with the production of new particles at a higher energy scale compared to the current experimental limits. The search for additional Higgs bosons is, in fact, predicted by theoretical extensions of the SM including the Minimal Supersymmetry Standard Model (MSSM). In the MSSM, the Higgs sector consists of two Higgs doublets, resulting in five physical Higgs particles: two charged bosons , two neutral scalars and , and one pseudoscalar . The work presented in this thesis is dedicated to the search of neutral non-Standard Model Higgs bosons decaying to two muons in the model independent MSSM scenario. Proton-proton collision data recorded by the CMS experiment at the CERN LHC at a center-of-mass energy of 13 TeV are used, corresponding to an integrated luminosity of . Such search is sensitive to neutral Higgs bosons produced either via gluon fusion process or in association with a quark pair. The extensive usage of Machine and Deep Learning techniques is a fundamental element in the discrimination between signal and background simulated events. A new network structure called parameterised Neural Network (pNN) has been implemented, replacing a whole set of single neural networks trained at a specific mass hypothesis value with a single neural network able to generalise well and interpolate in the entire mass range considered. The results of the pNN signal/background discrimination are used to set a model independent 95\% confidence level expected upper limit on the production cross section times branching ratio, for a generic boson decaying into a muon pair in the 130 to 1000 GeV range
Metrological characterization of sensors and instrumentation for distribution grid monitoring and electrical asset diagnostics
Get PDFThe Smart Grid needs a large amount of information to be operated and day by day new information is required to improve the operation performance. It is also fundamental that the available information is reliable and accurate. Therefore, the role of metrology is crucial, especially if applied to the distribution grid monitoring and the electrical assets diagnostics. This dissertation aims at better understanding the sensors and the instrumentation employed by the power system operators in the above-mentioned applications and studying new solutions. Concerning the research on the measurement applied to the electrical asset diagnostics: an innovative drone-based measurement system is proposed for monitoring medium voltage surge arresters. This system is described, and its metrological characterization is presented. On the other hand, the research regarding the measurements applied to the grid monitoring consists of three parts. The first part concerns the metrological characterization of the electronic energy meters’ operation under off-nominal power conditions. Original test procedures have been designed for both frequency and harmonic distortion as influence quantities, aiming at defining realistic scenarios. The second part deals with medium voltage inductive current transformers. An in-depth investigation on their accuracy behavior in presence of harmonic distortion is carried out by applying realistic current waveforms. The accuracy has been evaluated by means of the composite error index and its approximated version. Based on the same test setup, a closed-form expression for the measured current total harmonic distortion uncertainty estimation has been experimentally validated. The metrological characterization of a virtual phasor measurement unit is the subject of the third and last part: first, a calibrator has been designed and the uncertainty associated with its steady-state reference phasor has been evaluated; then this calibrator acted as a reference, and it has been used to characterize the phasor measurement unit implemented within a real-time simulator
Theoretical and experimental study of novel hybrid composite and metal-composites interfaces
Get PDFThe growing demand for lightweight solutions in every field of engineering is driving the industry to seek new technological solutions to exploit the full potential of different materials. The combination of dissimilar materials with distinct property ranges embodies a transparent allocation of component functions while allowing an optimal mix of their characteristics. From both technological and design perspectives, the interaction between dissimilar materials can lead to severe defects that compromise a multi-material hybrid component's performance and its structural integrity. This thesis aims to develop methodologies for designing, manufacturing, and monitoring of hybrid metal-composite joints and hybrid composite components. In Chapter 1, a methodology for designing and manufacturing hybrid aluminum/composite co-cured tubes is assessed. In Chapter 2, a full-field methodology for fiber misalignment detection and stiffness prediction for hybrid, long fiber reinforced composite systems is shown and demonstrated. Chapter 3 reports the development of a novel technology for joining short fiber systems and metals in a one-step co-curing process using lattice structures. Chapter 4 is dedicated to a novel analytical framework for the design optimization of two lattice architectures.La crescente domanda di soluzioni alleggerite in ogni campo dell'ingegneria, sta spingendo l'industria a cercare nuove soluzioni tecnologiche per sfruttare il pieno potenziale dei diversi materiali. La combinazione di materiali diversi con gamme di proprietà specifiche racchiude in sé una trasparente ripartizione delle funzioni fra componenti, consentendo al contempo un connubio ottimale delle loro caratteristiche. Sia dal punto di vista della progettazione che del processo, l'interazione tra materiali differenti può portare a gravi difetti che compromettono le prestazioni di un componente, anche nell’integrità strutturale. Questa tesi mira a sviluppare metodologie per la produzione, la progettazione ed il controllo di componenti ibridi metallo-composito e compositi ibridi. Nel Capitolo 1, viene esposta una metodologia per la progettazione e la produzione di tubi ibridi in alluminio/composito co-curati. Nel Capitolo 2, viene mostrata e dimostrata una metodologia full-field per il rilevamento del disallineamento delle fibre e la previsione della rigidezza per sistemi fibrorinforzati a fibra lunga. Il capitolo 3 riporta lo sviluppo di una nuova tecnologia per l'unione compositi a fibra corta e metallo in processo di co-curing, utilizzando lattice structures. Il capitolo 4 è dedicato a un nuovo quadro analitico per l'ottimizzazione del design di due tipologie di lattice structure
RF energy harvesting solutions for electromagnetic harsh environments: from industrial plants to wearable/implantable devices
Get PDFThe presented Thesis describes the design of RF-energy harvesting systems with applications on different environments, from the biomedical side to the industrial one, tackling the common thread problem which is the design of complete energy autonomous tags each of them with its dedicated purpose. This Thesis gathers a work of three years in the field of energy harvesting system design, a combination of full-wave electromagnetic
designs to optimize not only the antenna performance but also to fulfill the requirements given by each case study such as dimensions, insensitivity from the surrounding environment, flexibility and compliance with regulations. The research activity has been based on the development of highly-demanded ideas and real-case necessities which are in line with the environment in which modern IoT applications can really make a positive contribution. The Thesis is organized as follows: the first application, described in Chapter 2, regards the design and experimental validations of a rotation-insensitive WPT system for implantable devices.
Chapter 3 presents the design of a wearable energy autonomous detector to identify the presence of ethanol on the body surface.
Chapter 4 describes investigations in the use of Bessel Beam launchers for creating a
highly-focused energy harvesting link for wearable applications. Reduced dimensions, high focusing and decoupling from the human body are the key points to be addressed during the full-wave design and nonlinear optimization of the receiver antenna. Finally, Chapter 5 presents an energy autonomous system exploiting LoRa (Long Range) nodes for tracking trailers in industrial plants.
The novelty behind this design lies on the aim of obtaining a perfectly scalable system that exploits not only EH basic operating system but embeds a seamless solution for collecting a certain amount of power that varies with respect the received power level on the antenna, without the need of additional off-the-shelf components
Rising China and Internet governance: Multistakeholderism, fragmentation and the Liberal Order in the age of digital sovereignty
Get PDFIn its open and private-based dimension, the Internet is the epitome of the Liberal International Order in its global spatial dimension. Therefore, normative questions arise from the emergence of powerful non-liberal actors such as China in Internet governance. In particular, China has supported a UN-based multilateral Internet governance model based on state sovereignty aimed at replacing the existing ICANN-based multistakeholder model. While persistent, this debate has become less dualistic through time. However, fear of Internet fragmentation has increased as the US-China technological competition grew harsher.
This thesis inquires “(To what extent) are Chinese stakeholders reshaping the rules of Global Internet Governance?”. This is further unpacked in three smaller questions: (i) (To what extent) are Chinese stakeholders contributing to increased state influence in multistakeholder fora?; (ii) (how) is China contributing to Internet fragmentation?; and (iii) what are the main drivers of Chinese stakeholders’ stances?
To answer these questions, Chinese stakeholders’ actions are observed in the making and management of critical Internet resources at the IETF and ICANN respectively, and in mobile connectivity standard-making at 3GPP. Through the lens of norm entrepreneurship in regime complexes, this thesis interprets changes and persistence in the Internet governance normative order and Chinese attitudes towards it. Three research methods are employed: network analysis, semi-structured expert interviews, and thematic document analysis.
While China has enhanced state intervention in several technological fields, fostering debates on digital sovereignty, this research finds that the Chinese government does not exert full control on its domestic private actors and concludes that Chinese stakeholders have increasingly adapted to multistakeholder Internet governance as they grew influential within it. To enhance control over Internet-based activities, the Chinese government resorted to regulatory and technical control domestically rather than establishing a splinternet. This is due to Chinese stakeholders’ interest in retaining the network benefits of global interconnectivity
On the manuscript tradition of Aelius Aristides' sacred tales
Get PDFIl presente lavoro consiste in uno studio della tradizione manoscritta dei Discorsi sacri (= DS) di Elio Aristide. Nel primo capitolo si presenta una descrizione dettagliata dei testimoni superstiti (tutti collazionati integralmente), talvolta ridatati su base paleografica; nel secondo si dimostra l’esistenza di un archetipo (O) a monte della trasmissione dell’opera aristidea; nel terzo, quarto e quinto si ricostruiscono gli stemmata codicum delle tradizioni, rispettivamente, di DS 1-2 (bipartita), 3-5 (monopartita) e 6 (monopartita); nel sesto – e ultimo – capitolo si ricostruisce la storia della circolazione dei DS dall’epoca di Areta di Cesarea al tardo XV sec. A completamento e supporto della ricerca sono offerte numerose tavole dei manoscritti esaminati nonché un indice dei codici collazionati.This research consists in a study of the textual tradition of Aelius Aristides’ Sacred Tales (= ST). The first chapter presents a detailed description of the extant manuscripts (all collated entirely), sometimes re-dated on the basis of palaeographical evidence; the second shows the existence of an archetype for the transmission of the Aristidean oeuvre; the third, fourth and fifth aim to build stemmata codicum for the traditions of ST 1-2 (bipartite), 3-5 (monopartite) and 6 (monopartite), respectively; the sixth – and last – chapter reconstructs the circulation of the ST from the age of Arethas of Caesarea to the late XV century. To complete and support the research, numerous plates of the examined manuscripts are offered along with an index of the collated codices
Myanmar higher education in transition: the interplay between state authority, student politics and international actors.
Get PDFThe Myanmar “period of transition” (2011-2021) has often been described as a puzzle. Various scholars have begun to engage with the Myanmar context in an effort to grasp the essence of the transition it underwent during President Thein Sein’s USPD and Aung San Suu Kyi’s NLD governments. My work focuses on a specific policy sector, higher education, with a view to contributing to this scholarly debate regarding what was actually happening inside this complex country “transition”, especially in terms of collective participation in the process of political and social change. Reviewing existing scholarly literature on the politics of higher education, my study employs a triangle of analysis in which higher education reform is framed as the interplay of action on the part of “state authority”, “student politics” and “international actors”. What does this interplay lens reveal if we consider Myanmar’s “period of transition”? I argue that it shows the ambiguity and contradiction of tangible pushes for progressive social change that coexisted with authoritarian currents and the reinforcement of the societal position of dominant elites. At the policy level, ultimately, a convergence of interests between international actors and state authority served as the force driving the new higher education reform towards a neo-liberal model of governance and autonomy. This work unpacks the higher education reform process thanks to qualitative data gathered through extensive participant observation, in-depth interviewing and critical discourse analysis, shedding light on the rich narratives of those involved in the politics of higher education in Myanmar
Paradigms e contrario in Xenophon. A study of negative characters through narrative strategies and stylistic choices
Get PDFLa presente indagine di ricerca si concentra sulle opere storiografiche di Senofonte, focalizzandosi in modo particolare su quelle figure minori presenti in esse, che mostrano caratteristiche o comportamenti tali da renderle indegne del ruolo di governo che occupano. Da tempo, infatti, la critica si è focalizzata nell’individuare e analizzare quei personaggi che rappresentano il perfetto modello di leadership descritto da Senofonte e offerto all’imitazione del suo pubblico. Tuttavia, ben poco si è detto riguardo le figure opposte, quei paradigmi e contrario, destinati non tanto ad essere imitati, ma utili, piuttosto, a rappresentare gli errori che un lettore deve evitare e a far risaltare ancor di più i modelli di leadership illuminata e capace che sono il reale focus dell’attenzione di Senofonte in diverse opere. Se, infatti, è evidente la volontà e le caratteristiche paideutiche del corpus senofonteo, destinato ad insegnare le qualità, politiche ma ancor di più morali, necessarie per ricoprire un ruolo di governo e guida; sembrerebbe logico ipotizzare che questo fine didattico delle opere di Senofonte possa trovare realizzazione anche nelle figure negative, il cui ruolo è sottolineato ed evidenziato dall’autore attraverso strategie letterarie sempre nuove.The present research investigation concentrates on Xenophon's historiographical works, focusing in particular on those minor figures in them who display characteristics or behaviour that render them unworthy of the governing role they occupy. Critics have long focused on identifying and analysing those characters who represent the perfect model of leadership described by Xenophon and offered for imitation by his audience. However, very little has been said about the opposite figures, those paradigms and opposites, destined not so much to be imitated, but rather useful in representing the mistakes that a reader must avoid and to bring out even more the models of enlightened and capable leadership that are the real focus of Xenophon's attention in various works. If, in fact, the paideutic intention and characteristics of the Senofonte corpus is evident, intended to teach the qualities, political but even more so moral, necessary to hold a role of government and leadership; it would seem logical to assume that this didactic purpose of Xenophon's works can also be realised in the negative figures, whose role is emphasised and highlighted by the author through ever new literary strategies
Bukovina and the "ethnographic literature" in German language
Get PDFLa Bukowina è una regione dell’impero asburgico ricordata come “eccezionale” per la compresenza e la tolleranza fra etnie, nonché per l’accoglienza unica della lingua tedesca. Questa narrazione proviene e dai nostalgici ricordi delle ultime generazioni di abitanti del luogo, che in seguito hanno vissuto la fine del “mondo di ieri”; e da un discorso propagandistico della Corona. La presente ricerca si propone di illustrare il paesaggio culturale della Bukowina nonché le reali modalità con cui la cultura dell’imperatore si insinuò nella regione. Nel decodificare il rapporto di superiorità con cui il tedesco si affacciava agli altri popoli – investigato con l’ausilio dei postcolonial studies –, il progetto propone come materia di studio un fenomeno letterario in voga a cavallo tra XIX e XX secolo, la “letteratura etnografica”, ispirato dall’affascinante molteplicità della Bukowina, nonché da una disciplina accademica che in quegli anni attirava molti studiosi e curiosi: l’etnografia. Questo tipo di letteratura si esprime attraverso diversi generi letterari, che spesso condividono il tratto della frammentarietà. Tra queste opere, la presente analisi si sofferma su tre esempi che mostrano un progressivo allontanamento dal metodo “scientifico” della disciplina etnografica, illustrando l’ampiezza dell’insieme “letteratura etnografica”: "Die Völkergruppen der Bukowina" (1884) di Ludwig Adolf Staufe Simiginowicz; "Aus Halb-Asien" (1876-1888) di Karl Emil Franzos; "Maghrebinische Geschichten" (1953), di Gregor von Rezzori.The Bukovina region is recorded as a paradigm for the Habsburg mythical tolerance towards ethnicities and as a “German phenomenon”, since the emperor’s language was accepted here in such a welcoming way like in no other periphery. This narration comes on one side from the nostalgic memories of the inhabitants of the last generation, who later faced the end of “the world of yesterday”; on the other, from the propagandistic political discourse of the Monarchy. This study aims to illustrate the cultural landscape of the region and the actual way in which German language insinuated itself in the local social structure, trying to shed light on the reality behind the myth. By decoding the dominant position of German culture with the aid of postcolonial studies, the project presents as a subject of investigation a literary phenomenon at the turn of the 19th and the 20th century: “ethnographic literature”. In particular, the research focuses on three case studies, which are different in genre and observational approach towards the others: Ludwig Adolf Staufe Simiginowicz’ "Die Völkergruppen der Bukowina" (1884); Karl Emil Franzos’ "Aus Halb-Asien" (1876-1888); Gregor von Rezzori’s "Maghrebinische Geschichten" (1953)
Valorization of bio-alcohols into added value chemicals
Get PDFThe present research work focused on the valorisation and upgrading of bio-ethanol over heterogeneous catalysts in a lab-scale continuous gas-flow system. In the Unibo laboratories, catalytic tests have been carried out in the temperature range 300-600°C by feeding an ethanol/He mixture in the reactor. After choosing the reaction conditions, ion-exchanged hydroxyapatite with transition metals (i.e., Fe, Cu) and alkaline earth metal (i.e., Sr) have been synthesized and tested. The Sr-HAP catalyst led to the formation of a complex reaction mixture the composition of which need further optimization in order to fill the requisite to be used as fuel-blend. Then, some zirconium-oxide based catalysts have been prepared through two different methods, precipitation and hydrothermal, by varying some synthetic parameters (i.e., pH, the nature of the base) and by adding a transition metal as dopant agent (i.e., Ti and Y). The presence of a dopant into the zirconia structure favoured the stabilization of the tetragonal or cubic phase against the monoclinic one. Interestingly, 5%mol Ti-doped zirconia exhibited a different catalytic behaviour yielding diethyl ether as major product at 300°C, while all the others samples produced mainly ethylene. Then, the effect of acid-base properties of sepiolite, using alkali metals (i.e., Na, K, Cs) with different metal loading (i.e., 2, 4, 5, 7, 14 wt%) as promoters, and of the redox properties of sepiolite-supported CuO or NiO, on the catalytic conversion of ethanol into n-butanol has been investigated. Thermal treated sepiolite samples mainly acted as acid catalyst, yielding preferentially the dehydration products of ethanol (ethylene and diethyl ether). Best results in terms of activity (ethanol conversion, 59%) and n-butanol selectivity (30%) where obtained at 400ºC and a contact time, W/F, of 2 g/mL·s over the catalyst consisting of sepiolite calcined at 500ºC modified with 7 wt% of cesium