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Muon tomography for melting glaciers monitoring
Get PDFThis thesis presents the development of an innovative detector for muography, aimed at monitoring glacier melting. The process of glacier melting is not completely understood and is considered a crucial parameter in view of the global warming. Muography is a widely used technique, that takes advantages of the muon flux reaching Earth surface, employed to perform imaging of the inner structure of large objects, as volcanoes, container, and pyramids. The goal of our project is the development of a detector able to measure the glacier thickness with short exposure time, and with a real time data taking and processing, to perform studies of the seasonal behavior and the glacier melting trend through the years. Thanks to optimization studies through simulations, the developed detector has an angular resolution better than 5 mrad which results in an accuracy of less than 5 meters in the measurement of ice thickness, and a good reconstruction uniformity within the entire field of view. The read-out chain, based on FERS boards A5202, was fully tested and characterized, to ensure precision in measuring and analyzing muon flux. The development of a prototype confirmed the feasibility of the proposed design and validated the developed simulation. Preliminary tests shows good agreement between real data and simulated data
Improved operation of power distribution systems by the use of flexibility services and energy communities
Get PDFThis thesis investigates the operation of distribution systems incorporating flexibility service providers and renewable energy communities (RECs). It is structured in two main parts. The first part focuses on flexibility operations in electric vehicle (EV) parking lots (PLs) equipped with multiple charging stations. Due to uncertainties in EV arrivals and characteristics, a multistage stochastic approach is developed for day-ahead scheduling, enabling the calculation of the maximum flexibility PLs can offer to the distribution system operator (DSO). A k-medoid clustering method is used to reduce computational time. Flexibility is defined as the PL’s capacity to adjust power upon DSO request, with energy recovery to ensure EV charging requirements. The DSO leverages this flexibility, along with that from distributed energy resources (DERs), to optimize the voltage profile of the grid. A decentralized, multi-objective optimization framework is applied to a 24-hour simulation on the IEEE 123-node test feeder. Results show significant voltage profile improvements compared to scenarios without optimization. The second part explores reactive power services from RECs in medium-voltage networks. By coordinating active and reactive power exchanges among prosumers—particularly photovoltaic (PV) systems with battery energy storage (BESS)—RECs reduce penalties from low power factor operation. Voltage support is further enhanced using on-load tap changer (OLTC) transformers. Case studies include feeders in the Modena distribution network connected to a common substation. The findings confirm that RECs can reduce the need for new reactive compensation devices by effectively coordinating distributed generation. Additionally, the study examines the operation of multiple RECs within a single network. A novel pricing mechanism based on shadow prices of balancing constraints is proposed to ensure fair benefit distribution among members. While RECs significantly lower energy procurement costs, these benefits decrease as the number of communities in the same grid increases
Improving sustainability of electrochemical energy storage systems adopting novel solutions for different device components
Get PDFMy Ph. D work was focused on sustainable and safer energy storage systems. For that, I’ve considered to increase the overall sustainability of batteries through the implementation of biopolymers and to stabilize the life cycle and stability of lithium metal anodes that guarantees the highest energy density. At the very beginning I studied the implementation of chitosan, a renewable and biodegradable as binder for electrodes processed in aqueous environment and operating in different environments. With the experience gained with chitosan I tried to obtain a separator made of partially biodegradable polymers with phase inversion technique that could also be adopted for industrial production processes. In the end I tried to extend the idea of using biopolymers in batteries components by investigating the feasibility of polymeric electrolyte made of cellulose to increase the sustainability of the cells as well as improving the safety of lithium metal anodes reducing the risk of short circuits and cell failures
Mechanical performance of Arundo donax engineered panels: experimental and numerical approaches
Get PDFThe thesis explores the mechanical performance of panels made with Arundo donax (AD), a perennial herbaceous plant widely distributed in Italy. The research focused on the production and characterisation of three types of panels: 1. Honeycomb panels: These panels were designed with a core made of AD rings and skins of flax fibre reinforced with epoxy resin. Experimental tests, including three-point bending and pull-off tests, were conducted to evaluate the adhesion between the core and the skins. It was observed that roughening the outer surface of the AD rings significantly improves shear and bending mechanical properties. Additionally, a finite element model (FEM) was developed to predict the mechanical behaviour of the panels. 2. Sandwich particleboards: Produced in collaboration with Gruppo Saviola, these panels use a core made of recycled wood chips and AD particles. This project aimed to demonstrate that substituting recycled wood with AD can enhance the physical and mechanical performance of the panels. This material allowed the transition from non-structural to structural performing panels without increasing the resin content. 3. Binderless panels: Developed in collaboration with the start-up My.Fibres, these panels incorporate various aggregates, including AD and use pre-treated hemp fibres (Mytrill) as the matrix, through an innovative process. It was observed that the physical and mechanical properties of the material are independent of the type and nature of the aggregate used, while these properties improve with higher density and increased Mytrill content relative to the aggregate. This innovative approach aims to produce fully natural panels. The primary objective of the doctoral research was to demonstrate the feasibility and benefits both in terms of performance and the environmental impact of using natural materials as an alternative to traditional construction materials, thereby contributing to the green transition in the construction sector
Image-based 3D acquisition techniques and data sharing models in the field of cultural heritage
Get PDFLa presente ricerca si propone di analizzare i principali processi di acquisizione ed elaborazione reality-based adottati da esperti del settore, cercando di mettere in luce quali metodi e applicazioni vengono in genere adottati per comunicare la precisione e l’accuratezza dei risultati, nel complessivo contesto ben evidenziato dalla letteratura di riferimento circa l’assenza di schemi condivisi per la comunicazione dei risultati (Remondino et al. 2017, Lauro & Lombardo 2023). Le tecniche basate su immagini rappresentano certamente uno dei metodi più diffusi per la digitalizzazione dei beni culturali (Stathopoulou - Remondino 2019, De Paolis et al. 2020, Rahaman 2021, Agapiou 2023) e lo studio è appunto incentrato su queste metodologie. Al fine di individuare metodi capaci di trasmettere con maggiore trasparenza la complessità delle ricostruzioni eseguite e rendere gli output maggiormente comprensibili a un’utenza estesa, si è ritenuto funzionale adottare un approccio altamente trasversale, basato sulla revisione della letteratura riguardante tutte le principali fasi legate alla creazione e alla condivisione dei modelli 3D; al contempo, si è tuttavia anche cercato di mettere in luce in che modo le tecnologie attuali vengono utilizzare per documentare graficamente i processi intermedi delle ricostruzioni eseguite per restituirli infine alle comunità connesse. Partendo dall’analisi delle procedure di acquisizione ed elaborazione condotte su alcuni casi di studio, si è dunque rivolta un’indagine più approfondita non solo sugli output finali ma anche e soprattutto sulla documentazione tecnica riguardante, ad esempio, le stime di errore. Parallelamente nel lavoro vengono esaminati temi altrettanto significativi ed essenziali per le finalità dello studio, tra cui gli schemi di metadatazione e i sistemi di archiviazione più idonei alla conservazione dei dati 3D del Patrimonio Culturale. Ciò permetterà di capire anche quali sono le informazioni ritenute essenziali per la corretta trasmissione dei dati raccolti ed elaborati all’interno dei progetti di digitalizzazione.This research aims analysing the main reality-based acquisition and processing processes adopted by experts in the field, trying to highlight which methods and applications are generally adopted to communicate the precision and accuracy of results, in the overall context well highlighted by the reference literature concerning the absence of shared schemes for communicating results (Remondino et al. 2017, Lauro & Lombardo 2023). Image-based techniques certainly represent one of the most widespread methods for the digitisation of cultural heritage (Stathopoulou - Remondino 2019, De Paolis et al. 2020, Rahaman 2021, Agapiou 2023) and this study focuses on these methods. In order to identify methods able to more transparently convey the complexity of the reconstructions performed and to make the outputs more comprehensible to a broad user base, it was deemed functional to adopt a highly transversal approach, based on the review of the literature concerning all the main phases related to the creation and sharing of 3D models; at the same time, however, it was also attempted to shed light on how current technologies are used to graphically document the intermediate processes of the reconstructions performed in order to return them to the networked communities. Starting from the analysis of the acquisition and processing procedures conducted on some case studies, a more in-depth investigation was therefore directed not only at the final outputs but also above all at the technical documentation concerning, for example, error estimates. At the same time, issues as significant and essential for the purposes of the study are examined in the work, including the metadata schemes and archiving systems most appropriate for the preservation of 3D Cultural Heritage data. This will also provide an understanding of what information is considered essential for the correct transmission of the data collected and processed within digitisation projects
Climate services ecosystems
No full textDuring the last decade climate services have been exponentially proliferating in number and diversity. Without the profound understanding, coordination and synergies among the different climate services present in a particular country, society can miss opportunities to increase resilience to climate impacts, or -what is worse- the number and diversity of disconnected climate services available to stakeholders can delay, freeze or even dismantle ongoing adaptation strategies and action plans. Building healthy ecosystems of climate services is a way to guarantee that society enhances resilience, while optimally orchestrating the available resources. These ecosystems tend to be more robust to climate impacts than a collection of climate services focused on certain applications or just one sector, because shocks to one part of the ecosystem are redistributed and dampened through the entire network. This PhD dissertation describes the concept and elements of climate services ecosystems and introduces the use of Network Analysis and Dynamic Causal Network Theory to compare ecosystems of climate services. This approach provides an objective way to assess potential or actual causal relationships between their elements, the dynamics of their interactions and the value of the ecosystem. The climate services ecosystem approach assesses the value of an integrated collection of climate services, under forecasts and scenarios of a changing climate, changes in policies or interventions, changes of societal needs and limited budgets, supporting stakeholders to define what, when and how to fund climate services to enhance the resilience of communities and societies
Open RAN approaches for 6G Non-Terrestrial Networks
No full textThis thesis evaluates applying the O-RAN paradigm to NTNs to deliver flexible, interoperable and scalable terrestrial and non-terrestrial integrated 6G networks. After introducing O-RAN and SatCom fundamentals, it examines: (i) NTN architecture compatibility, (ii) virtualization and disaggregation, and (iii) near‑/real‑time control loops. Three integration architectures: Full‑gNB, Orbit‑split and Feeder‑split, are proposed to meet satellite mobility and latency constraints. A detailed study of eight functional split options shows that lower‑layer splits (Options 7, 6) struggle with high throughput and tight latency, whereas higher‑layer splits relax these limits but reduce control granularity; adaptive techniques are outlined to ease interface capacity and delay bottlenecks. Virtualized RAN and CN platforms simplify adoption of new 3GPP NTN features across Releases 17–19, enabling software‑only upgrades of gNBs, UEs and cores. Control‑loop research spans non‑RT, near‑RT and RT operations. A deep‑Q‑learning offloading strategy dynamically balances TN/NTN traffic, boosting spectral efficiency. A neural‑network CSI predictor counters channel aging from satellite motion, improving SCMA decoding accuracy. Finally, an AI‑driven CNF orchestration scheme employs multivariate LSTM forecasting to allocate resources proactively, reducing delay and energy use. Collectively, these contributions show that O-RAN principles, virtualization and AI can overcome NTN‑specific constraints and enable agile, sustainable and high‑performance 6G networks
Efficient solutions for GaN power amplifiers
No full textOver the past decade, wireless applications have expanded rapidly across sectors like cellular networks, vehicular communication, and industrial systems. The transition to 5G addresses these needs with enhanced reliability, low latency, and cost-effective solutions. To meet gigabit-level wireless traffic, millimeter-wave frequencies are essential. RF power amplifiers (PAs) are critical to boosting signals but face challenges with high peak-to-average-power-ratio (PAPR) signals in modern modulation schemes. Recent semiconductors such as Gallium Nitride (GaN) are promising solutions due to high power density and potential for integration. Moreover, dynamic adjustment of PA performance and multi-band operation are increasingly important. While many solutions exist, bandwidth and frequency constraints limit their commercial impact. Two key areas are addressed in this thesis for improving GaN PA efficiency. First, it delves into the impact of trapping effects, which can significantly degrade device performance. A new characterization technique is developed, based on drain current transient (DCT) measurements, to assess figures of merit such as gate and drain lag, trap activation energy, cross-section, and carrier density reduction. This approach reduces characterization time while providing valuable insights into the relationship between the physical structure of HEMTs and their susceptibility to trapping effects. The second focus is on integrating varactor devices into PA output matching networks to enable reconfigurable architectures. Existing GaN-on-SiC diodes are characterized to assess their viability as integrated alternatives to discrete components. After this preliminary research, the extraction of suitable models to allow CAD simulations is required. A novel automatic modeling procedure, employing vector network measurements, is developed to accurately characterize and model varactor device behavior. This procedure generates a lumped-element circuit representation, facilitating the simulation and optimization of the matching network for improved PA efficiency and adaptability. A matching network integrating varactors is also proposed and a preliminary evaluation of PAs with modified varactor devices is presented
The protection of culture in the European Union’s new generation preferential trade agreements
No full textSe, in un primo momento, la tematica culturale è stata presa in considerazione principalmente in relazione agli aspetti economici, nel corso degli anni, con l’avanzare del processo d’integrazione, l’approccio della Comunità prima, e dell’Unione poi, al cultural heritage ha conosciuto una significativa evoluzione. Oggi il tema risulta centrale, in quanto l’Unione europea sta compiendo notevoli sforzi per affermare una propria identità preservando chiaramente quelle dei propri Stati membri, e promuovendo analogo rispetto per cultura, diversità culturale più in generale del cultural heritage nelle sue relazioni esterne. La ricerca intende indagare l’evoluzione dell’approccio dell’Unione europea ai temi di tutela e promozione del cultural heritage con specifico riferimento alla disciplina presente nei nuovi accordi commerciali dell’UE. Prendendo avvio da una disamina della politica commerciale dell’Unione – una delle principali e più articolate competenze dell’UE – la nostra ricerca va, quindi, ad incentrarsi sugli accordi preferenziali di ultima generazione, strumenti notevolmente innovativi, che intervengono anche sulla tutela e promozione dei beni culturali, della diversità culturale, più in generale del cultural heritage nel dare spessore alla sostenibilità su cui intendono fondare l’ampia integrazione economica fra le parti contraenti. Un focus particolare verterà sugli Accordi con i Paesi caraibici, con la Corea del Sud e l’America Centrale in quanto, per il momento, unici esempi in cui i negoziati sono stati in grado di produrre uno specifico strumento dedicato alla cultura: il protocollo di cooperazione culturale. Più in generale, in riferimento a tutti i nuovi Free Trade Agreements (FTAs) dell’UE, verranno analizzate le diverse disposizioni dedicate al cultural heritage dedicate agli obblighi di libero scambio e alla tutela degli investimenti. Nelle conclusioni si valuterà l’adeguatezza dell’approccio dell’Unione a preservare le questioni di cultural heritage negli accordi di libero scambio.While cultural issues were at first considered mainly in relation to economic aspects, over the years, with the progress of the integration process, the approach of the Community first, and then the Union, to cultural heritage has undergone a significant evolution. Today, the issue is central, as the European Union is making considerable efforts to assert its own identity while clearly preserving that of its Member States and promoting similar respect for culture, cultural diversity more generally and cultural heritage in its external relations. This research aims to investigate the evolution of the European Union's approach to the protection and promotion of cultural heritage, with specific reference to the provisions contained in the EU's new trade agreements. Starting with an examination of the Union's trade policy – one of the EU's main and most complex competences – our research will then focus on the latest generation of preferential agreements, which are highly innovative instruments that also address the protection and promotion of cultural goods, cultural diversity and cultural heritage more generally, giving substance to the sustainability on which they intend to build broad economic integration between the contracting parties. Particular focus will be devoted to agreements with Caribbean countries, South Korea and Central America, as these are currently the only examples where negotiations have resulted in a specific instrument dedicated to culture: the cultural cooperation protocol. More broadly, with regard to all new EU Free Trade Agreements (FTAs), the various provisions dedicated to cultural heritage, free trade obligations and investment protection will be analysed. The conclusions will evaluate the adequacy of the EU's approach to preserving cultural heritage issues in free trade agreements
Advertising Self-regulation. Digital advertising. International, national and comparative aspects
No full textHá cerca de cinquenta anos, empresas de determinados setores começaram a adotar a autorregulação, criando e monitorando suas próprias regras em complementação ou substituição à legislação estatal. Em alguns casos, isso ocorreu com a participação do governo, caracterizando a corregulação. Esse modelo foi amplamente utilizado pela indústria da publicidade, inicialmente tradicional (offline) e, mais recentemente, digital. Impulsionada pelos avanços tecnológicos, a publicidade evoluiu para um modelo híbrido, combinando características do meio tradicional e digital. A transformação do setor contou com diversas influências: (i) os Estados Unidos foram pioneiros tanto na publicidade tradicional quanto na digital; (ii) organizações internacionais intergovernamentais, como ONU, UNCTAD, OCDE e UE, passaram a se interessar pela regulação do tema; (iii) organizações privadas como ICC e metarreguladoras como EASA e ICAS também contribuíram; e (iv) surgiram organizações específicas para a publicidade digital, como DAA, EDAA, IAB, TAG e W3C. Essa evolução tornou a publicidade um fenômeno global, ampliando seu escopo ao ponto de a expressão “publicidade” parecer insuficiente, sendo substituída por “comunicação comercial”. Esse processo gerou inúmeros documentos, tratados e leis, formando as fontes do direito publicitário. A análise dessas fontes permitiu: (i) visualizar o panorama geral do direito publicitário, (ii) avaliar a importância de cada fonte e (iii) esboçar uma quase-teoria geral sobre o tema. A tese organiza seus fundamentos sob três perspectivas: (i) internacional, devido à relevância da globalização no setor; (ii) nacional, com foco em exemplos como EUA, Itália e Brasil; e (iii) comparativa, substituindo a experimentação científica por métodos das humanidades, como análise descritiva, exploratória, histórica e dialética. Por fim, procura-se apontar possíveis futuras fontes de direito publicitário, consolidando uma visão científica do tema. Esse é o resumo da tese.About fifty years ago, companies in certain sectors began adopting self-regulation, creating and monitoring their own rules to complement or replace state legislation. In some cases, this occurred with government participation, characterizing co-regulation. This model was widely used by the advertising industry, initially traditional (offline) and, more recently, digital. Driven by technological advances, advertising evolved into a hybrid model, combining features of both traditional and digital platforms. This transformation was influenced by several factors: (i) the United States was a pioneering force, both in traditional and digital advertising; (ii) intergovernmental international organizations like the UN, UNCTAD, OECD, and EU became interested in regulating the topic; (iii) private organizations like the ICC and metaregulators such as EASA and ICAS also contributed; and (iv) specific organizations for digital advertising, such as DAA, EDAA, IAB, TAG, and W3C, emerged. This evolution turned advertising into a global phenomenon, expanding its scope to the point where the term "advertising" seemed insufficient, being replaced by "commercial communication." This process generated numerous documents, treaties, and laws, forming the sources of advertising law. Analyzing these sources enabled: (i) a comprehensive view of advertising law, (ii) an evaluation of the importance of each source, and (iii) the outline of a near-general theory on the subject. The thesis organizes its foundations through three perspectives: (i) international, due to the relevance of globalization in the sector; (ii) national, focusing on examples like the USA, Italy, and Brazil; and (iii) comparative, substituting scientific experimentation with humanities-based methods such as descriptive, exploratory, historical, and dialectical analysis. Finally, it seeks to identify potential future sources of advertising law, consolidating a scientific vision of the topic. This is the summary of the thesis