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3D high resolution techniques applied on small and medium size objects: from the analysis of the process towards quality assessment
Get PDFThe need for metric data acquisition is an issue strictly related to the human capability of describing the world with rigorous and repeatable methods. From the invention of photography to the development of advanced computers, the metric data acquisition has been subjected to rapid mutation, and nowadays there exists a strict connection between metric data acquisition and image processing, Computer Vision and Artificial Intelligence. The sensor devices for the 3D model generation are various and characterized by different functioning principles. In this work, optical passive and active sensors are treated, focusing specifically on close-range photogrammetry, Time of Flight (ToF) sensors and Structured-light scanners (SLS). Starting from the functioning principles of the techniques and showing some issues related to them, the work highlights their potentialities, analyzing the fundamental and most critical steps of the process leading to the quality assessment of the data. Central themes are the instruments calibration, the acquisition plan and the interpretation of the final results. The capability of the acquisition techniques to satisfy unconventional requirements in the field of Cultural Heritage is also shown. The thesis starts with an overview about the history and developments of 3D metric data acquisition. Chapter 1 treats the Human Vision System and presents a complete overview of 3D sensing devices. Chapter 2 starts from the enunciation of the basic principle of close-range photogrammetry considering digital cameras functioning principles, calibration issues, and the process leading to the 3D mesh reconstruction. The case of multi-image acquisition is analyzed, deepening the quality assessment of the photogrammetric process through a case study. Chapter 3 is devoted to the range-based acquisition techniques, namely ToF laser scanners and SLSs. Lastly, Chapter 4 focuses on unconventional applications of the mentioned high-resolution acquisition techniques showing some examples of study cases in the field of Cultural Heritage
Design, development, and analysis of hybrid metal-composite tube for industrial application
Get PDFIn the aerospace, automotive, printing, and sports industries, the development of hybrid Carbon Fiber Reinforced Polymer (CFRP)-metal components is becoming increasingly important. The coupling of metal with CFRP in axial symmetric components results in reduced production costs and increased mechanical properties such as bending, torsional stiffness, mass reduction, damping, and critical speed compared to the single material-built
ones.
In this thesis, thanks to a novel methodology involving a rubbery/viscoelastic interface layer, several hybrid aluminum-CFRP prototype tubes were produced. Besides, an innovative system for the cure of the CFRP part has been studied, analyzed, tested, and developed in the company that financed these research activities (Reglass SRL, Minerbio BO, Italy). The residual thermal stresses and strains have been investigated with numerical models based on the Finite Element Method (FEM) and compared with experimental tests. Thanks to numerical models, it was also possible to reduce residual thermal stresses by optimizing the lamination sequence of CFRP and determining the influence of the system parameters.
A novel software and methodology for evaluating mechanical and damping properties of specimens and tubes made in CFRP were also developed. Moreover, to increase the component's damping properties, rubber nanofibers have been produced and interposed throughout the lamination of specimens. The promising results indicated that the nanofibrous mat could improve the material damping factor over 77% and be adopted in CFRP components with a negligible increment of weight or losing mechanical properties
Use of electronic health data for the identification of cases and for the evaluation of healthcare consumptions and chronic kidney disease costs
Get PDFIntroduction
Chronic kidney disease (CKD) is a common condition characterized by a gradual loss of kidney function and consequently increasing costs associated with the disease.
Aims
The aim was to use administrative databases and a pathology registry to characterize CKD patient according to their stage and to evaluate the burden of disease; to identify incident patients on dialysis; to investigate the impact of COVID-19 on mortality in CKD patients.
Methods
Data from a regional pathology registry and administrative databases were used to classify CKD patients into different disease progression subgroups (CT-PIRP classification) using the following 6 variables: age, sex, diabetes, glomerular filtration rate, proteinuria, phosphate level and different CKD stages (3a, 3b, 4, 5). Healthcare consumptions and costs were evaluated. Incident chronic dialysis patients were defined those seen regularly in outpatient clinics. The incidence and mortality of COVID-19 among CKD patients were estimated.
Results
The study cohort includes 7737 CKD patients, aged 73.2±11.6 years, 64.5% males, mostly stage 4 (3136, 40.5%) and 3b (2799, 36.2%). Average annual costs were significantly higher for CT-PIRP groups 2 and 3 (€7239 and €8825 respectively) and more than twofold higher for CKD stage 5 (€7,993) compared to stage 3a (€3,973).
Both algorithms used to identify incident chronic dialysis patients had high sensitivity, 90.8% and 88.4%, high positive predictive value (84.0% and 82.0%) and high agreement (77.4% and 74.1%).
The incidence of COVID-19 infection was 4.16%. COVID-19 hospitalized patients were the 95.5%, those on home isolation were the 3.6% and the 0.9% were asymptomatic. Compared to those without COVID-19, the overall excess mortality ranged between 34.4% and 56.3%.
Conclusion
Administrative databases are a powerful tool to describe the burden of CKD disease, in order to assess the interventions aimed at reducing the impact of CKD and improving the quality of care of CKD patients
Advanced Spectroscopy for the Study of Colourants in Cultural Heritage
Get PDFColourants are substances used to change the colour of something, and are classified in three typology of colorants: a) pigments, b) dyes, and c) lakes and hybrid pigments. Their identification is very important when studying cultural heritage; it gives information about the artistic technique, can help in dating, and offers insights on the condition of the object. Besides, the study of the degradation phenomena constitutes a framework for the preventive conservation strategies, provides evidence of the object's original appearance, and contributes to the authentication of works of art. However, the complexity of these systems makes it impossible to achieve a complete understanding using a single technique, making necessary a multi-analytical approach.
This work focuses on the set-up and application of advanced spectroscopic methods for the study of colourants in cultural heritage.
The first chapter presents the identification of modern synthetic organic pigments using Metal Underlayer-ATR (MU-ATR), and the characterization of synthetic dyes extracted from wool fibres using a combination of Thin Layer Chromatography (TLC) coupled to MU-ATR using AgI@Au plates.
The second chapter presents the study of the effect of metallic Ag in the photo-oxidation process of orpiment, and the influence of the different factors, such as light and relative humidity. We used a combination of vibrational and synchrotron radiation-based X-ray microspectroscopy techniques: µ-ATR-FT-IR, µ-Raman, SR-µ-XRF, µ-XANES at S K-, Ag L3- and As K-edges and SR-µ-XRD.
The third chapter presents the study of metal carboxylates in paintings, specifically on the formation of Zn and Pb carboxylates in three different binders: stand linseed oil, whole egg, and beeswax. We used micro-ATR-FT-IR, macro FT-IR in total reflection (rMA-FT-IR), portable Near-Infrared spectroscopy (NIR), macro X-ray Powder Diffraction (MA-XRPD), XRPD, and Gas Chromatography Mass-Spectrometry (GC-MS). For the data processing, we explored the data from rMA-FT-IR and NIR with the Principal Component Analysis (PCA)
Enabling Human Centric Smart Campuses via Edge Computing and Connected Objects
Get PDFEarly definitions of Smart Building focused almost entirely on the technology aspect and did not suggest user interaction at all. Indeed, today we would attribute it more to the concept of the automated building. In this sense, control of comfort conditions inside buildings is a problem that is being well investigated, since it has a direct effect on users’ productivity and an indirect effect on energy saving. Therefore, from the users’ perspective, a typical environment can be considered comfortable, if it’s capable of providing adequate thermal comfort, visual comfort and indoor air quality conditions and acoustic comfort. In the last years, the scientific community has dealt with many challenges, especially from a technological point of view. For instance, smart sensing devices, the internet, and communication technologies have enabled a new paradigm called Edge computing that brings computation and data storage closer to the location where it is needed, to improve response times and save bandwidth. This has allowed us to improve services, sustainability and decision making. Many solutions have been implemented such as smart classrooms, controlling the thermal condition of the building, monitoring HVAC data for energy-efficient of the campus and so forth. Though these projects provide to the realization of smart campus, a framework for smart campus is yet to be determined. These new technologies have also introduced new research challenges: within this thesis work, some of the principal open challenges will be faced, proposing a new conceptual framework, technologies and tools to move forward the actual implementation of smart campuses. Keeping in mind, several problems known in the literature have been investigated: the occupancy detection, noise monitoring for acoustic comfort, context awareness inside the building, wayfinding indoor, strategic deployment for air quality and books preserving
Improving water use efficiency of vegetable as part of integrated sustainable agriculture management for smallholders and landless in the tropics
Get PDFWater is essential for agricultural production and food security of the world population. In the coming decades, a growing number of regions will face increasing water scarcity while, due to the global population expected to reach more than 9 billion people by 2050, demand for food is expected to surge by more than 50%. Considering that about 70% of global freshwater withdrawals are directly used in agriculture, accurate management of agricultural water resources to increase crop WUE is one of the main targets in research on plant-soil-water relations. Different strategies are available to predict soil water availability for plants and maximize crop water use efficiency. Novel irrigation technologies need to be adapted to local environmental conditions and available technical solutions, particularly in simplified growing systems generally found in developing countries. Proper management of irrigation can be beneficial for the farmers since it improves and stabilizes yield in water shortages. Furthermore, it can lower the competition for water use among domestic, industrial, and agricultural sectors. The thesis analyzes the use of natural resources for vegetable production. It is based on improving water resources management in vegetable cultivation both in rural and urban environments. Currently, urban agriculture is increasingly widespread and consolidated, and for this reason, users must also apply agricultural technologies to maximize the efficiency of natural resources contributing to environmental sustainability. Improving water use efficiency in horticulture is a key issue in ensuring its environmental sustainability in rural and urban environments. Moreover, the selection of drought-resistant varieties and crop diversification also play an essential role in obtaining sustainably the production necessary to meet the world's population's growing food requirements. This dissertation's scenario adopts innovative and rational irrigation strategies to increase water use efficiency on both on-soil and simplified soilless systems in different urban and rural environments, mainly in Tropical contexts
Design of experiment in drug development: optimal allocations in multi-arm clinical trials and design space for multi-step processes
Get PDFIn this thesis, we deal with the design of experiments in the drug development process, focusing on the design of clinical trials for treatment comparisons (Part I) and the design of preclinical laboratory experiments for proteins development and manufacturing (Part II).
In Part I we propose a multi-purpose design methodology for sequential clinical trials. We derived optimal allocations of patients to treatments for testing the efficacy of several experimental groups by also taking into account ethical considerations. We first consider exponential responses for survival trials and we then present a unified framework for heteroscedastic experimental groups that encompasses the general ANOVA set-up. The very good performance of the suggested optimal allocations, in terms of both inferential and ethical characteristics, are illustrated analytically and through several numerical examples, also performing comparisons with other designs proposed in the literature.
Part II concerns the planning of experiments for processes composed of multiple steps in the context of preclinical drug development and manufacturing. Following the Quality by Design paradigm, the objective of the multi-step design strategy is the definition of the manufacturing design space of the whole process and, as we consider the interactions among the subsequent steps, our proposal ensures the quality and the safety of the final product, by enabling more flexibility and process robustness in the manufacturing
Measurement of the atmospheric electron and muon neutrino flux with the ANTARES neutrino telescope
Get PDFThis thesis presents a combined measurement of the energy spectra of atmospheric electron and muon neutrinos in the energy range between around 100 GeV and 50 TeV with the ANTARES neutrino telescope. The analysis uses 3012 days of detector livetime in the period from 2007 to 2017, and selects 1016 neutrino interacting in (or close to) the instrumented volume of the detector, yielding shower-like events and starting track events. The contamination by atmospheric muons is suppressed at the level of a few per mill by different steps in the selection analysis, including a Boosted Decision Tree classifier. The distribution of reconstructed events is unfolded in terms of electron and muon neutrino fluxes and the derived energy spectra are compared with previous measurements
The Stones of Eternity. The Jewish Cemeteries of Ferrara in the Light of the Community Registers and in the Epitaphs of the Funerary Stelae
Get PDFL’elaborato di tesi ha come soggetto i sei cimiteri ebraici detenuti e utilizzati dalle Nazioni israelitiche di Ferrara nel corso della storia, ossia i quattro terreni italo-ashkenaziti e i due terreni ispano-levantini. Nella prima parte della tesi si approfondiscono gli avvicendamenti e l’evoluzione delle varie aree di inumazione attraverso una grande quantità di fonti documentarie inedite, in prevalenza rintracciate nel fondo ferrarese dei CAHJP di Gerusalemme. Le ricostruzioni storiche sono infatti arricchite dai dati contenuti nei pinqasim comunitari, registri redatti dai Consigli o dalle Confraternite ebraiche durante il regolare svolgimento delle proprie attività. In questa prima sezione sono stati inoltre inseriti due significativi approfondimenti legati ai cimiteri ebraici di Ferrara: il primo sulla violazione delle sepolture e il secondo sulle interdizioni e il riutilizzo delle stele funerarie. La ricerca si conclude con l’analisi delle fonti epigrafiche tuttora presenti in città. Dopo un’introduzione metodologica e contestuale sulle testimonianze funerarie superstiti, è presentato – sulla base dell’eterogeneità temporale, stilistica e contenutistica – un campione di circa 100 lapidi conservate nel grande cimitero ebraico di via delle Vigne, di cui è stato trascritto e tradotto l’epitaffio.The thesis concerns the six Jewish cemeteries held and used by the Jewish Nations of Ferrara throughout history, namely the four Italo-Ashkenazi grounds and the two Hispano-Levantine grounds. In the first part of the thesis, the changes and evolution of the various burial areas are explored through a large number of unpublished documentary sources, mostly found in the Ferrara collection of the CAHJP in Jerusalem. The historical reconstructions are enriched by the data contained in the community pinkassim, registers drawn up by the Jewish Councils or Confraternities during the regular conduct of their activities. In this first section, two significant insights related to the Jewish cemeteries of Ferrara have also been included: the first on the violation of burials and the second on the interdictions and reuse of funerary stelae. The research ends with the analysis of the epigraphic sources still present in the city. After a methodological and contextual introduction on the surviving funerary evidence, a sample of about 100 tombstones preserved in the large Jewish cemetery in via delle Vigne is presented - on the basis of temporal, stylistic and content heterogeneity - and the epitaphs have been transcribed and translated
Fabrication of supercapacitors based on cellulose nanocomposites for use in biological fuel cell
Get PDFThe aim of this Ph.D. thesis is to develop novel concepts of super-capacitive Microbial Fuel Cells (MFCs) by focusing on nanocomposite anodes and cathodes constructed from low-cost bacterial cellulose (BC), carbon materials, and conductive polymers.
The use of BC, a biopolymer synthesized by some species of bacteria, as a porous media membrane for fabricating a capacitive membrane electrode assembly (MEA) in MFC was performed by a novel method. Binder-less coating of that side of BC, exposed to the air, with CNTs made a homogeneous coating by which the impedance of the MEA decreased noticeably. On the other side of BC, exposed to anolyte, Nano zycosil (NZ) coating could create a barrier to oxygen cross-over and prevent anolyte leakage. This monolithic MEA structure with a low expense of fabrication is introduced for the first time in this thesis. MFC performance in the presence of the cellulosic MEA compared with the GDE showed higher power density, lower internal resistance, higher catalytic activity, and higher capacitance.
BC-based anodes demonstrated excellent capacitance. BC-CNT was covered with polyaniline (PANI) through pulse electro-polymerization in this work. CNTs and PANI as super-capacitive materials showed different capacitance trends vs. anodic biofilm formation. PANI as a biocompatible conductive polymer provided a better condition on BC-CNT-PANI anode for microbial colonization. The effect of PANI on the capacitive response of biofilm by impedance was studied for the first time. Finally, MFC performance was improved by short-circuiting BC-CNT to a high capacitance PANI-modified BC-CNT as an additional anode giving rise to enhancing double-layer capacitance of anode and thus higher apparent capacitance and power density of the cell