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Decentralized systems for the protection and portability of personal data
Get PDFThe General Data Protection Regulation (GDPR) has been designed to help promote a view in favor of the interests of individuals instead of large corporations. However, there is the need of more dedicated technologies that can help companies comply with GDPR while enabling people to exercise their rights. We argue that such a dedicated solution must address two main issues: the need for more transparency towards individuals regarding the management of their personal information and their often hindered ability to access and make interoperable personal data in a way that the exercise of one's rights would result in straightforward. We aim to provide a system that helps to push personal data management towards the individual's control, i.e., a personal information management system (PIMS). By using distributed storage and decentralized computing networks to control online services, users' personal information could be shifted towards those directly concerned, i.e., the data subjects. The use of Distributed Ledger Technologies (DLTs) and Decentralized File Storage (DFS) as an implementation of decentralized systems is of paramount importance in this case. The structure of this dissertation follows an incremental approach to describing a set of decentralized systems and models that revolves around personal data and their subjects. Each chapter of this dissertation builds up the previous one and discusses the technical implementation of a system and its relation with the corresponding regulations. We refer to the EU regulatory framework, including GDPR, eIDAS, and Data Governance Act, to build our final system architecture's functional and non-functional drivers. In our PIMS design, personal data is kept in a Personal Data Space (PDS) consisting of encrypted personal data referring to the subject stored in a DFS. On top of that, a network of authorization servers acts as a data intermediary to provide access to potential data recipients through smart contracts
Numerical modelling of rock masses interacting with dams: the case of Ridracoli
Get PDFA three-dimensional Direct Finite Element procedure is here presented which takes into account most of the factors affecting the interaction problem of the dam-water-foundation system, whilst keeping the computational cost at a reasonable level by introducing some simplified hypotheses. A truncated domain is defined, and the dynamic behaviour of the system is treated as a wave-scattering problem where the presence of the dam perturbs an original free-field system. The rock foundation truncated boundaries are enclosed by a set of free-field one-dimensional and two-dimensional systems which transmit the effective forces to the main model and apply adsorbing viscous boundaries to ensure radiation damping. The water domain is treated as an added mass moving with the dam. A strategy is proposed to keep the viscous dampers at the boundaries unloaded during the initial phases of analysis, when the static loads are initialised, and thus avoid spurious displacements. A focus is given to the nonlinear behaviour of the rock foundation, with concentrated plasticity along the natural discontinuities of the rock mass, immersed in an otherwise linear elastic medium with Rayleigh damping. The entire procedure is implemented in the commercial software Abaqus®, whose base code is enriched with specific user subroutines when needed. All the extra coding is attached to the Thesis and tested against analytical results and simple examples. Possible rock wedge instabilities induced by intense ground motion, which are not easily investigated within a comprehensive model of the dam-water-foundation system, are treated separately with a simplified decoupled dynamic approach derived from the classical Newmark method, integrated with FE calculation of dam thrust on the wedges during the earthquake. Both the described approaches are applied to the case study of the Ridracoli arch-gravity dam (Italy) in order to investigate its seismic response to the Maximum Credible Earthquake (MCE) in a full reservoir condition
Test vector generation for the phase II ATLAS event filter trigger upgrade
Get PDFIn the near future, the LHC experiments will continue to be upgraded as the LHC luminosity will increase from the design 1034 to 7.5 × 1034, with the HL-LHC project, to reach 3000 × f b−1 of accumulated statistics. After the end of a period of data collection, CERN will face a long shutdown to improve overall performance by upgrading the experiments and implementing more advanced technologies and infrastructures. In particular, ATLAS will upgrade parts of the detector, the trigger, and the data acquisition system.
It will also implement new strategies and algorithms for processing and transferring the data to the final storage. This PhD thesis presents a study of a new pattern recognition algorithm to be used in the trigger system, which is a software designed to provide the information necessary to select physical events from background data. The idea is to use the well-known Hough Transform mathematical formula as an algorithm for detecting
particle trajectories. The effectiveness of the algorithm has already been validated in the past, independently of particle physics applications, to detect generic shapes in images. Here, a software emulation tool is proposed for the hardware implementation of the Hough Transform, to reconstruct the tracks in the ATLAS Trigger and Data Acquisition system. Until now, it has never been implemented on electronics in particle physics experiments, and as a hardware implementation it would provide overall latency benefits.
A comparison between the simulated data and the physical system was performed on a Xilinx UltraScale+ FPGA device
Italian GenZ celebrity. Teen celebrities in contemporary italian audiovisual production: reconfigurations, communication models, classifications.
Get PDFLa ricerca si pone l’obiettivo di comprendere in che modo sia strutturato lo stardom italiano della Generazione Z e quale ruolo svolgano i media nei processi di celebrification delle figure attoriali in esame, nonché l'impatto che queste hanno sulla società stessa. Si intende fornire una maggiore comprensione dei meccanismi alla base del funzionamento dello star system in un contesto storico, culturale e generazionale specifico. Inoltre, il confronto tra il panorama italiano e il landscape internazionale contribuisce a una maggiore comprensione dell’evoluzione e della trasformazione del concetto di celebrità nel contesto globale, oltre che delle modalità attraverso le quali la dimensione italiana si inserisce in questa evoluzione.The research aims to understand how the Italian stardom of Generation Z is structured and what role media plays in the celebrification processes of the acting figures being examined, as well as their impact on society itself. The goal is to provide a deeper understanding of the mechanisms behind the functioning of the star system in a specific historical, cultural, and generational context. Furthermore, the comparison between the Italian and international landscape contributes to a greater understanding of the evolution and transformation of the concept of celebrity in a global context, as well as the ways in which the Italian dimension fits into this evolution
Hybrid ground-aerial mesh networks for IoT monitoring applications: network design and software platform development
Get PDFThe Internet of Things (IoT) has grown rapidly in recent years, leading to an increased need for efficient and secure communication between connected devices. Wireless Sensor Networks (WSNs) are composed of small, low-power devices that are capable of sensing and exchanging data, and are often used in IoT applications. In addition, Mesh WSNs involve intermediate nodes forwarding data to ensure more robust communication. The integration of Unmanned Aerial Vehicles (UAVs) in Mesh WSNs has emerged as a promising solution for increasing the effectiveness of data collection, as UAVs can act as mobile relays, providing
extended communication range and reducing energy consumption. However, the integration of UAVs and Mesh WSNs still poses new challenges, such as the design of efficient control and communication strategies.
This thesis explores the networking capabilities of WSNs and investigates how the integration of UAVs can enhance their performance. The research focuses on three main objectives: (1) Ground Wireless Mesh Sensor Networks, (2) Aerial Wireless Mesh Sensor Networks, and (3) Ground/Aerial WMSN integration. For the first objective, we investigate the use of the Bluetooth Mesh standard for IoT monitoring in different environments. The second objective focuses on deploying aerial nodes to maximize data collection effectiveness and QoS of UAV-to-UAV links while maintaining the aerial mesh connectivity. The third objective investigates hybrid WMSN scenarios with air-to-ground communication links. One of the main contribution of the thesis consists in the design and implementation of a software framework called "Uhura", which enables the creation of Hybrid Wireless Mesh Sensor Networks and abstracts and handles multiple M2M communication stacks on both ground and aerial links. The operations of Uhura have been validated through simulations and small-scale testbeds involving ground and aerial devices
Nanocomposites based on poly(caprolactone)-chitosan electrospun nanofibers and metallic oxide nanoparticles. Their potential use to adsorption and photocatalytic degradation of organic contaminants
Get PDFPollution of water bodies is one of the most common environmental problems today. Organic pollutants are one of the main drawbacks in this natural resource, among which the following stand out long-lived dyes, pharmaceuticals, and pesticides. This research aims at obtaining nanocomposites based on polycaprolactone-chitosan (PCL-CS) electrospun nanofibers (NFs) containing TiO2 nanoparticles (NPs) for the adsorption and photocatalytic degradation of organic pollutants, using Rhodamine B as a model. The fabricated hybrid materials were characterized by FT-IR, TGA, DSC, SEM, TEM, tensile properties, and the contact angle of water drops. The photoactivity of the NFs was investigated using a batch-type system by following UV-Vis absorbance and fluorescence of rhodamine B (RhB).
For this purpose, TiO2NPs were successfully ex-situ incorporated into the polymer matrix promoting good mechanical properties and higher hydrophilicity of the material. The results showed that CS in the NFs increased the absorption and degradation of RhB by the TiO2NPs. CS attracted the pollutant molecules to the active sites vicinity of TiO2NPs, favoring initial adsorption and degradation. In other words, a bait-hook-and-destroy effect was evidenced. It also was demonstrated that the sensitization of TiO2 by organic dyes (e.g., perylene derivative) considerably improves the photocatalytic activity under visible radiation, allowing the use of low amounts of TiO2. (≈0.05 g/1 g of fiber). Hence, the current study is expected to contribute with an environmentally friendly green alternative solution
The cosmic ray tagger of the ICARUS detector: construction, commissioning and performances in the first physics run
Get PDFThe Short Baseline Neutrino Program at Fermilab aims to confirm or definitely rule out the existence of sterile neutrinos at the eV mass scale. The program will perform the most sensitive search in both the nue appearance and numu disappearance channels along the Booster Neutrino Beamline. The far detector, ICARUS-T600, is a high-granularity Liquid Argon Time Projection Chamber located at 600 m from the Booster neutrino source and at shallow depth, thus exposed to a large flux of cosmic particles. Additionally, ICARUS is located 6 degrees off axis with respect to the Neutrino beam from the Main Injector. This thesis presents the construction, installation and commissioning of the ICARUS Cosmic Ray Tagger system, providing a 4 pi coverage of the active liquid argon volume. By exploiting only the precise nanosecond scale synchronization of the cosmic tagger and the PMT optical flashes it is possible to determine if an event was likely triggered by a cosmic particle. The results show that using the Top Cosmic Ray Tagger alone a conservative rejection larger than 65% of the cosmic induced background can be achieved. Additionally, by requiring the absence of hits in the whole cosmic tagger system it is possible to perform a pre-selection of contained neutrino events ahead of the full event reconstruction
<Melek over all the earth> The roots of Israelite monotheism as a reflection of the idea of divine kingship in pre-exilic times
Get PDFQuesta tesi è un contributo al dibattito meta-terminologico sull'uso scientifico del termine "monoteismo" in relazione alla religione dell'Israele antico. L'attenzione è rivolta principalmente a un tema specifico: l'esplorazione della nozione teistica di "esistenza" divina (implicita nell'uso di "monoteismo" come lente di osservazione) e il problema della sua applicazione alle concettualizzazioni della divinità che emergono nella Bibbia ebraica. In primo luogo, il "monoteismo" come termine e concetto viene ricondotto alle sue origini storiche nell'ambiente intellettuale del platonismo di Cambridge nell'Inghilterra del XVII secolo. Poi, si affronta il dibattito contemporaneo sull'uso del termine "monoteismo" in relazione alla religione dell'Israele antico e si evidenzia il ruolo dell'"esistenza" teistica come lente distorcente nella lettura dei testi biblici. La maggior parte della tesi sostiene questo assunto con una lettura esegetica dettagliata di tre passi biblici scelti come casi di studio: Sal 82; 1Re 18,20-40* e Zc 14,9. Queste analisi mostrano come la nozione teistica di un'esistenza divina astratta non sia in grado di spiegare la rappresentazione del divino che emerge da questi testi. Allo stesso tempo, il potere divino come categoria euristica viene proposto come un'alternativa più adatta a spiegare queste concettualizzazioni della divinità. L'ultima sezione elabora ulteriormente questi risultati. Qui la regalità di YHWH, come immagine metaforica del suo potere, viene utilizzata per descrivere i cambiamenti nella concettualizzazione di questa divinità. L'argomentazione finale è che in nessuna parte del materiale biblico affrontato in questa tesi si trova una nozione simile a quella di esistenza divina astratta. Poiché tale nozione è implicita nell'uso del termine "monoteismo", questi risultati richiedono una considerazione ancora più attenta del suo uso nel dibattito scientifico.This dissertation is a contribution to the meta-terminological debate about the scholarly use of the term “monotheism” in relation to ancient Israelite religion. Its primary focus is narrowed on a specific topic: the exploration of the theistic notion of divine “existence” (embedded in the use of “monotheism” as a reading lens) and the problem of its application to conceptualizations of divinity that stem from the Hebrew Bible.
First, “monotheism” as a term and a concept is traced down to its historical origins in the intellectual environment of Cambridge Platonism in 17th-century England. Then, the contemporary debate about the use of the term “monotheism” in relation to ancient Israelite religion will be addressed, and the role of theistic “existence” as a distorting lens to read biblical data highlighted.
The bulk of the dissertation substantiates this assumption with a detailed exegetical reading of three biblical passages selected as case-studies: Ps 82; 1 Kings 18:20-40* and Zech 14:9. These examinations show how the theistic notion of an abstract divine existence falls short in elucidating the representation of divinity displayed in these texts. At the same time, divine power as a heuristic category is proposed as a more fitting alternative to account for such conceptualizations of divinity.
The last section further elaborates these results. Here YHWH’s kingship, as a metaphorical image of his power, is used to describe changes in the conceptualization of this god and his relations with other deities.
The final argument is made that nowhere in the source material of the Hebrew Bible addressed in this dissertation a notion similar to that of abstract divine existence is found. Since such a notion is implied in the use of the term “monotheism”, these results call for an even more careful consideration of its use in scholarly discourse
Contributions to the performance analysis of continuum parallel robots
Get PDFContinuum parallel robots (CPRs) are manipulators employing multiple flexible beams arranged in parallel and connected to a rigid end-effector. CPRs promise higher payload and accuracy than serial CRs while keeping great flexibility. As the risk of injury during accidental contacts between a human and a CPR should be reduced, CPRs may be used in large-scale collaborative tasks or assisted robotic surgery. There exist various CPR designs, but the prototype conception is rarely based on performance considerations, and the CPRs realization in mainly based on intuitions or rigid-link parallel manipulators architectures. This thesis focuses on the performance analysis of CPRs, and the tools needed for such evaluation, such as workspace computation algorithms. In particular, workspace computation strategies for CPRs are essential for the performance assessment, since the CPRs workspace may be used as a performance index or it can serve for optimal-design tools. Two new workspace computation algorithms are proposed in this manuscript, the former focusing on the workspace volume computation and the certification of its numerical results, while the latter aims at computing the workspace boundary only. Due to the elastic nature of CPRs, a key performance indicator for these robots is the stability of their equilibrium configurations. This thesis proposes the experimental validation of the equilibrium stability assessment on a real prototype, demonstrating limitations of some commonly used assumptions. Additionally, a performance index measuring the distance to instability is originally proposed in this manuscript. Differently from the majority of the existing approaches, the clear advantage of the proposed index is a sound physical meaning; accordingly, the index can be used for a more straightforward performance quantification, and to derive robot specifications
Models for reliability estimation of HVDC cable systems
Get PDFThe work carried out in this thesis aims at:
- studying – in both simulative and experimental methods – the effect of electrical transients (i.e., Voltage Polarity Reversals VPRs, Temporary OverVoltages TOVs, and Superimposed Switching Impulses SSIs) on the aging phenomena in HVDC extruded cable insulations. Dielectric spectroscopy, conductivity measurements, Fourier Transform Infra-Red FTIR spectroscopy, and space charge measurements show variation in the insulating properties of the aged Cross-Linked Polyethylene XLPE specimens compared to non-aged ones. Scission in XLPE bonds and formation of aging chemical bonds is also noticed in aged insulations due to possible oxidation reactions. The aged materials show more ability to accumulate space charges compared to non-aged ones. An increase in both DC electrical conductivity and imaginary permittivity has been also noticed.
- The development of life-based geometric design of HVDC cables in a detailed parametric analysis of all parameters that affect the design. Furthermore, the effect of both electrical and thermal transients on the design is also investigated.
- The intrinsic thermal instability in HVDC cables and the effect of insulation characteristics on the thermal stability using a temperature and field iterative loop (using numerical methods – Finite Difference Method FDM). The dielectric loss coefficient is also calculated for DC cables and found to be less than that in AC cables. This emphasizes that the intrinsic thermal instability is critical in HVDC cables.
- Fitting electrical conductivity models to the experimental measurements using both models found in the literature and modified models to find the best fit by considering the synergistic effect between field and temperature coefficients of electrical conductivity