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Study of the calorimetric performance of a liquid Argon detector based on a novel optical imaging concept
Get PDFDUNE is a next-generation long-baseline neutrino oscillation experiment. It aims to measure the still unknown violation phase and the sign of , which defines the neutrino mass ordering. DUNE will exploit a Far Detector composed of four multi-kiloton LArTPCs, and a Near Detector (ND) complex located close to the neutrino source at Fermilab.
The SAND detector at the ND complex is designed to perform on-axis beam monitoring, constrain uncertainties in the oscillation analysis and perform precision neutrino physics measurements. SAND includes a 0.6 T super-conductive magnet, an electromagnetic calorimeter, a 1-ton liquid Argon detector - GRAIN - and a modular, low-density straw tube target tracker system. GRAIN is an innovative LAr detector where neutrino interactions can be reconstructed using only the LAr scintillation light imaged by an optical system based on Coded Aperture masks and lenses - a novel approach never used before in particle physics applications. In this thesis, a first evaluation of GRAIN track reconstruction and calorimetric capabilities was obtained with an optical system based on Coded Aperture cameras.
A simulation of interactions with the energy spectrum expected at the future Fermilab Long Baseline Neutrino Facility (LBNF) was performed. The performance of SAND was evaluated, combining the information provided by all its sub-detectors, on the selection of sample and on the neutrino energy reconstruction
On making web accessibility more accessible: strategy and tools for social good
Get PDFThe world currently faces a paradox in terms of accessibility for people with disabilities. While digital technologies hold immense potential to improve their quality of life, the majority of web content still exhibits critical accessibility issues. This PhD thesis addresses this challenge by proposing two interconnected research branches.
The first introduces a groundbreaking approach to improving web accessibility by rethinking how it is approached, making it more accessible itself. It involves the development of:
1. AX, a declarative framework of web components that enforces the generation of accessible markup by means of static analysis.
2. An innovative accessibility testing and evaluation methodology, which communicates test results by exploiting concepts that developers are already familiar with (visual rendering and mouse operability) to convey the accessibility of a page. This methodology is implemented through the SAHARIAN browser extension.
3. A11A, a categorized and structured collection of curated accessibility resources aimed at facilitating their intended audiences discover and use them.
The second branch focuses on unleashing the full potential of digital technologies to improve accessibility in the physical world. The thesis proposes the SCAMP methodology to make scientific artifacts accessible to blind, visually impaired individuals, and the general public. It enhances the natural characteristics of objects, making them more accessible through interactive, multimodal, and multisensory experiences. Additionally, the prototype of \gls{a11yvt}, a system supporting accessible virtual tours, is presented. It provides blind and visually impaired individuals with features necessary to explore unfamiliar indoor environments, while maintaining universal design principles that makes it suitable for usage by the general public.
The thesis extensively discusses the theoretical foundations, design, development, and unique characteristics of these innovative tools. Usability tests with the intended target audiences demonstrate the effectiveness of the proposed artifacts, suggesting their potential to significantly improve the current state of accessibility
Study of charm hadronisation in pp collisions at = 13 TeV with the ALICE experiment
Get PDFIn high-energy hadron collisions, the production at parton level of heavy-flavour quarks (charm and bottom) is described by perturbative Quantum Chromo-dynamics (pQCD) calculations, given the hard scale set by the quark masses. However, in hadron-hadron collisions, the predictions of the heavy-flavour hadrons eventually produced entail the knowledge of the parton distribution functions, as well as an accurate description of the hadronisation process. The latter is taken into account via the fragmentation functions measured at ee colliders or in ep collisions, but several observations in LHC Run 1 and Run 2 data challenged this picture. In this dissertation, I studied the charm hadronisation in proton-proton collision at = 13 TeV with the ALICE experiment at the LHC, making use of a large statistic data sample collected during LHC Run 2. The production of heavy-flavour in this collision system will be discussed, also describing various hadronisation models implemented in commonly used event generators, which try to reproduce experimental data, taking into account the unexpected results at LHC regarding the enhanced production of charmed baryons. The role of multiple parton interaction (MPI) will also be presented and how it affects the total charm production as a function of multiplicity. The ALICE apparatus will be described before moving to the experimental results, which are related to the measurement of relative production rates of the charm hadrons and , which allow us to study the hadronisation mechanisms of charm quarks and to give constraints to different hadronisation models. Furthermore, the analysis of D mesons (, and ) as a function of charged-particle multiplicity and spherocity will be shown, investigating the role of multi-parton interactions. This research is relevant per se and for the mission of the ALICE experiment at the LHC, which is devoted to the study of Quark-Gluon Plasma
Interfaces between national and EU law: time limits in cross-border civil proceedings and their impact on the free circulation of judgments
Get PDFThe thesis aims at exploring possible legal solutions to remove the obstacles to the free circulation of judgments in the civil justice area that arise from the remarkably diverging national rules on procedural time limits.
As shown by the case-law of the CJEU, time limits have recently come under closer scrutiny. The interplay between national and EU law illustrates that time limits raise significant deficiencies connected with the right to a fair trial under Art. 6 ECHR and Art. 47 CFR – e.g. the effective recovery of claims, effective judicial protection, effective cross-border enforcement of judgments – which negatively impact EU cross-border civil litigation.
In order to overcome some of the weaknesses of the current legal framework governing the cross-border enforcement of judgments and strengthen the parties’ fundamental procedural rights the PhD thesis intends to determine whether and, to what extent time limits can be harmonised at EU level. EU action on time limits would indeed favour the speed, efficiency and proportionality of cross-border proceedings without sacrificing the fairness of the judicial process and the equality of the partie
Exploiting spectrally resolved satellite observations to assess the performance of climate models
Get PDFThe accurate representation of the Earth Radiation Budget by General Circulation Models (GCMs) is a fundamental requirement to provide reliable historical and future climate simulations.
In this study, we found reasonable agreement between the integrated energy fluxes at the top of the atmosphere simulated by 34 state-of-the-art climate models and the observations provided by the Cloud and Earth Radiant Energy System (CERES) mission on a global scale, but large regional biases have been detected throughout the globe. Furthermore, we highlighted that a good agreement between simulated and observed integrated Outgoing Longwave Radiation (OLR) fluxes may be obtained from the cancellation of opposite-in-sign systematic errors, localized in different spectral ranges. To avoid this and to understand the causes of these biases, we compared the observed Earth emission spectra, measured by the Infrared Atmospheric Sounding Interferometer (IASI) in the period 2008-2016, with the synthetic radiances computed on the basis of the atmospheric fields provided by the EC-Earth GCM. To this purpose, the fast σ-IASI radiative transfer model was used, after its validation and implementation in EC-Earth.
From the comparison between observed and simulated spectral radiances, a positive temperature bias in the stratosphere and a negative temperature bias in the middle troposphere, as well as a dry bias of the water vapor concentration in the upper troposphere, have been identified in the EC-Earth climate model. The analysis has been performed in clear-sky conditions, but the feasibility of its extension in the presence of clouds, whose impact on the radiation represents the greatest source of uncertainty in climate models, has also been proven.
Finally, the analysis of simulated and observed OLR trends indicated good agreement and provided detailed information on the spectral fingerprints of the evolution of the main climate variables
Potential theory on metric spaces
Get PDFThis work revolves around potential theory in metric spaces, focusing on applications of dyadic potential theory to general problems associated to functional analysis and harmonic analysis. In the first part of this work we consider the weighted dual dyadic Hardy's inequality over dyadic trees and we use the Bellman function method to characterize the weights for which the inequality holds, and find the optimal constant for which our statement holds. We also show that our Bellman function is the solution to a stochastic optimal control problem. In the second part of this work we consider the problem of quasi-additivity formulas for the Riesz capacity in metric spaces and we prove formulas of quasi-additivity in the setting of the tree boundaries and in the setting of Ahlfors-regular spaces. We also consider a proper Harmonic extension to one additional variable of Riesz potentials of functions on a compact Ahlfors-regular space and we use our quasi-additivity formula to prove a result of tangential convergence of the harmonic extension of the Riesz potential up to an exceptional set of null measur
Studio pancreatic cystic follow-up, an international collaboration (PACYFIC study). Prospective Evaluation of pancreatic cysts surveillance based on European consensus of pancreatic cystic tumors
Get PDFIntroduzione
Nel 2014 è stato proposto un protocollo di studio riguardante la sorveglianza delle lesioni cistiche del pancreas (intese come IPMN) e denominato PACYFIC Study.
Obiettivi
Obiettivo primario era di stabilire l’impatto di un programma di sorveglianza in termini di pazienti arruolati e pazienti con indicazione chirurgica.
Obiettivi secondari erano: 1) stabilire l’impatto dei fattori demografici, clinici, radiologici e della strategia di sorveglianza sull’indicazione chirurgica, sulla capacità individuare le lesioni maligne, sulla sopravvivenza.
Materiali e Metodi
Lo studio su cui si è basata la raccolta dei dati è uno studio di tipo prospettico, di coorte, multicentrico, internazionale. Lo studio ha incluso gli individui con una IPMN, di nuova o pregressa diagnosi, che giustifichi una sorveglianza o il trattamento chirurgico.
I dati clinici, demografici, radiologici e chirurgici sono stati raccolti in un database prospettico.
Le variabili discrete sono state espresse come frequenza e percentuale. Le continue come medie e deviazioni standard o mediane e range interquartile (IQR). Per l’analisi statistica sono stati utilizzati il test di Fischer, il test del Chi quadro, il test di Spearman, il test di Student. L’analisi multivariata è stata eseguita utilizzando la regressione logistica espressa come Odds Ratio e intervallo di confidenza al 95 %.
Per la sopravvivenza è stato utilizzato il metodo di Kaplan-Meier. L’analisi multivariata sulle sopravvivenze è stata eseguita mediante la regressione di Cox.
Risultati
Il protocollo di sorveglianza ha permesso l'arruolamento di 516 pazienti. 53 pazienti hanno raggiunto l'indicazione chirurgica.
La sopravvivenza globale della coorte è stata di 326.8± 9.1 mesi. I fattori predittivi la sopravvivenza sono risultati età (OR 1.07, P-value<0.001), sesso (OR 1.82, P-value=0.006), ittero, noduli murali (OR 4.84, P-value=0.018 e OR 2.19, P-value=0.016), chirurgia (OR 0.46, P-value 0.038).
Conclusioni
L'introduzione del protocollo di sorveglianza ha portato ad un aumento di identificazione di lesioni e ha avuto impatto sulla sopravvivenzaIntroduction
Uncertanty regarding behaviour of IPMN has generated numerous guidelines. IN 2014 a prospective international study (PACYFIC) has proposed a surveillance protocol, which is used in this thesis.
Objectives
Primary objective was to evaluate the impact of the surveillance in terms of patients enrolled and indications to surgery.
Secondary objectives were to establish the impact of clinical, demographics and radiologic factors in predicting surgery, malignancy and overall survival
Materials and Methods
Clinical, demographic and radiological work up data has been collected in prospective database from june 2014 until november 2022.
Univariate and multivariate analysis were performed to establish the impact of the surveillance protocol and of the aforementioned factors in predicting surgical indication, presence of malignancy and overall survival.
Discrete variables have been reported as frequency and percentage, continuous variables have been reported as mean and standard deviation or median and interquartile range. Univariate analysis was performed using Fisher's T test and CHi square test, Spearman test was used for ordinal scales. Multivariate analysisi was performed using logistic regression. Survival analysis was performed using Kaplan Meier method and multivariat Hazard Ratio was computed usinng Cox's regression.
Results
The total number of patients enrolled has been 516. 53 patients reached criteria for resection.
Surveillance protocol increased the risk of surgical indication (O R 1.11 (0.36) p<0.002).
The cohort overall survival was 326.8± 9.1 months. Factors predicting OS were age (OR 1.07, P-value<0.001), sex
(OR 1.82, P-value=0.006), jaundice and presence of solid nodule in IPMN (OR 4.84, P-value=0.018 e OR 2.19, P-value=0.016), surgery (OR 0.46, P-value 0.038).
Conclusions
THe adoption of a surveillance protocol increased the capacity to identify IPMNs and impacted surviva
Work inclusion between access and participation
Get PDFLa Convenzione delle Nazioni Unite sui Diritti delle Persone con Disabilità (UNCRPD) riconosce il diritto di tutte le persone al lavoro “gli Stati Parti adottano misure adeguate a garantire alle persone con disabilità, su base di uguaglianza con gli altri, l’accesso all’ambiente fisico, ai trasporti, all’informazione e alla comunicazione, compresi i sistemi e le tecnologie di informazione e comunicazione e ad altre attrezzature e servizi aperti o forniti al pubblico”(United Nation 2016 p.14). Nonostante i progressi (in ambito politico culturale) che si stanno compiendo in ambito internazionale in termini di pari opportunità e di inclusione, le persone in situazione di disabilità continuano a incontrare barriere che limitano la loro partecipazione attiva al mondo del lavoro.
A partire da questo scenario, la ricerca si propone di indagare i bisogni (es. di accoglienza, di accesso al contesto fisico e digitale, di partecipazione nella vita dell’azienda ecc.) delle persone con disabilità e di sviluppare una applicazione digitale (web app), rivolta alle imprese, finalizzata a monitorare e a promuovere l'inclusione lavorativa.
Ripercorrendo il modello di progettazione del design thinking e valorizzando un processo di ricerca basato su metodi misti (qualitativi e qualitativi) è stato ideato Job inclusion for all; un ambiente digitale fondato sull’adattamento di due strumenti di “metariflessione”: l’Index for inclusion job version e l’employment role mapping.
Lo strumento digitale prototipato è stato testato e validato, durante l’ultimo anno di ricerca, da parte di una equipe multidisciplinare internazionale; tale processo ha consentito di raccogliere feedback (rispetto alla rilevanza e alla chiarezza degli item, rispetto ai punti di forza e di debolezza) che hanno consentito di migliorare e implementare la versione finale del prototipo di web app.The United Nations Convention on the Rights of Persons with Disabilities (UNCRPD) recognises the right of all persons to work: "States Parties shall take appropriate measures to ensure to persons with disabilities access, on an equal basis with others, to the physical environment, to transportation, to information and communications, including information and communications technologies and systems, and to other facilities and services open or provided to the public." (United Nations 2016, Art.9 p. 14). Despite the progress made internationally in terms of equal opportunities and inclusion (in the political and cultural sphere), people with disabilities continue to encounter barriers that limit their active participation in the world of work.
Starting from this scenario, the research proposes to study the needs (e.g. reception, access to the physical and digital environment, participation in the life of the company, etc.) of people with disabilities and to develop a digital application (web application), addressed to companies, aimed at monitoring and promoting employment inclusion.
Following the “Design Thinking” model and valorising a research process based on mixed methods (qualitative and quantitative), Job Inclusion for All was designed, a digital environment based on the adaptation of two "meta-reflection" tools: the “Index for Inclusion Job Version” and the “Employment Role Mapping”.
The prototype of the digital tool was tested and validated by an international multidisciplinary team during the last year of the research; this process made it possible to collect feedback (in terms of relevance and clarity of the items, in terms of strengths and weaknesses) that made it possible to improve and implement the final version of the prototype web application
Working the time. Employee's rights between technique and society
Get PDFLa dimensione giuridica del tempo, cioè il ruolo del tempo nel diritto, ha contribuito a far emergere il lavoro quale concetto legale astratto dal prestatore, funzionale alla sua alienazione. Rompere l’unitarietà del tempo della persona, per consacrarne una parte al lavoro, ha dato ai rapporti di potere tra gli individui una forma giuridica in grado di legittimarli. Il primo capitolo si sofferma sulla costruzione legale del lavoro subordinato attraverso la definizione del suo tempo. Tra gli elementi essenziali del contratto tipizzato dall’art. 2094 c.c., il tempo nella causa, oltre a mostrare la non istantaneità dello scambio e la indeterminatezza del regolamento contrattuale, non assurge a criterio discretivo dalle collaborazioni o dal lavoro autonomo. Se dalla causa si passa ad indagare l’oggetto, l’interprete si imbatte nel pudore di svelare quale sia il vero elemento su cui incide il contratto, la persona del lavoratore, che induce a prediligere la finzione di allontanare l’attività dal corpo di chi la produce: l’orario è la tecnica giuridica che rende possibile la partecipazione del lavoro ad una logica di scambio. Il secondo e il terzo capitolo si concentrano sulla regolazione e interpretazione del tempo di lavoro in chiave diacronica. La legislazione lavoristica ha trovato i propri albori nella disciplina eteronoma dell’orario, come strumento per tutelare i prestatori dagli eccessi mercantilistici. L’attuale quadro normativo è molto attento alle ragioni creditorie ma la giurisprudenza della Corte di giustizia testimonia l’irrequietudine di una materia viva e in movimento. Non è un caso che il legislatore europeo, nei piccoli passi compiuti per rafforzare il diritto sociale comune agli Stati membri, abbia assegnato al tempo un ruolo centrale, come prevedibilità delle condizioni di lavoro (direttiva n. 1152 del 2019), come equilibrio tra attività professionale e vita familiare (direttiva n. 1158 del 2019) e un domani, forse, come diritto alla disconnessione.This doctoral thesis examines the role of time in three different dimensions of labour law. In the legal definition of subordination (Article 2094 of the Italian Civil Code), time becomes a key to understanding the cause and the object of the work contract, both of which are essential elements of any type of contract according to Article 1325 of the Civil Code. In the working time, the definition of time turns into a legal technique to protect the workers’ rights. In the European social law, time is enriched by new meaning: in the Directive 2019/1152 as predictability of working conditions, in the Directive 2019/1158 as an instrument to ensure work-life balance for parents and carers, in the European Parliament’s legislative initiative regulating the right to switch off from work-related tasks and devices, as a right to disconnect
Qualification of optical fiber sensors for the structural health monitoring of aerospace structures
Get PDFIn recent years, composite materials have revolutionized the design of many structures. Their superior mechanical properties and light weight make composites convenient over traditional metal structures for many applications. However, composite materials are susceptible to complex and challenging to predict damage behaviors due to their anisotropy nature. Therefore, structural Health Monitoring (SHM) can be a valuable tool to assess the damage and understand the physics underneath. Distributed Optical Fiber Sensors (DOFS) can be used to monitor several types of damage in composites. However, their implementation outside academia is still unsatisfactory. One of the hindrances is the lack of a rigorous methodology for uncertainty quantification, which is essential for the performance assessment of the monitoring system. The concept of Probability of Detection (POD) must function as the guiding light in this process. However, precautions must be taken since this tool was established for Non-Destructive Evaluation (NDE) rather than Structural Health Monitoring (SHM). In addition, although DOFS have been the object of numerous studies, a well-established POD methodology for their performance assessment is still missing. This thesis aims to develop a methodology to produce POD curves for DOFS in composite materials. The problem is analyzed considering several critical points, such as the strain transfer characterizing the DOFS and the development of an experimental and model-assisted methodology to understand the parameters that affect the DOFS performance