3D Surveying and Data Management towards the Realization of a Knowledge System for Cultural Heritage

The research activities involved the application of the Geomatic techniques in the Cultural Heritage field, following the development of two themes: Firstly, the application of high precision surveying techniques for the restoration and interpretation of relevant monuments and archaeological finds. The main case regards the activities for the generation of a high-fidelity 3D model of the Fountain of Neptune in Bologna. In this work, aimed to the restoration of the manufacture, both the geometrical and radiometrical aspects were crucial. The final product was the base of a 3D information system representing a shared tool where the different figures involved in the restoration activities shared their contribution in a multidisciplinary approach. Secondly, the arrangement of 3D databases for a Building Information Modeling (BIM) approach, in a process which involves the generation and management of digital representations of physical and functional characteristics of historical buildings, towards a so-called Historical Building Information Model (HBIM). A first application was conducted for the San Michele in Acerboli’s church in Santarcangelo di Romagna. The survey was performed by the integration of the classical and modern Geomatic techniques and the point cloud representing the church was used for the development of a HBIM model, where the relevant information connected to the building could be stored and georeferenced. A second application regards the domus of Obellio Firmo in Pompeii, surveyed by the integration of the classical and modern Geomatic techniques. An historical analysis permitted the definitions of phases and the organization of a database of materials and constructive elements. The goal is the obtaining of a federate model able to manage the different aspects: documental, analytic and reconstructive ones.

Machine learning per l'idrologia: applicazione del metodo random forests per la previsione degli eventi di piena fluviale con un approccio probabilistico

Le tecniche di Machine Learning sono molto utili in quanto consento di massimizzare l’utilizzo delle informazioni in tempo reale. Il metodo Random Forests può essere annoverato tra le tecniche di Machine Learning più recenti e performanti. Sfruttando le caratteristiche e le potenzialità di questo metodo, la presente tesi di dottorato affronta due casi di studio differenti; grazie ai quali è stato possibile elaborare due differenti modelli previsionali. Il primo caso di studio si è incentrato sui principali fiumi della regione Emilia-Romagna, caratterizzati da tempi di risposta molto brevi. La scelta di questi fiumi non è stata casuale: negli ultimi anni, infatti, in detti bacini si sono verificati diversi eventi di piena, in gran parte di tipo “flash flood”. Il secondo caso di studio riguarda le sezioni principali del fiume Po, dove il tempo di propagazione dell’onda di piena è maggiore rispetto ai corsi d’acqua del primo caso di studio analizzato. Partendo da una grande quantità di dati, il primo passo è stato selezionare e definire i dati in ingresso in funzione degli obiettivi da raggiungere, per entrambi i casi studio. Per l’elaborazione del modello relativo ai fiumi dell’Emilia-Romagna, sono stati presi in considerazione esclusivamente i dati osservati; a differenza del bacino del fiume Po in cui ai dati osservati sono stati affiancati anche i dati di previsione provenienti dalla catena modellistica Mike11 NAM/HD. Sfruttando una delle principali caratteristiche del metodo Random Forests, è stata stimata una probabilità di accadimento: questo aspetto è fondamentale sia nella fase tecnica che in fase decisionale per qualsiasi attività di intervento di protezione civile. L'elaborazione dei dati e i dati sviluppati sono stati effettuati in ambiente R. Al termine della fase di validazione, gli incoraggianti risultati ottenuti hanno permesso di inserire il modello sviluppato nel primo caso studio all’interno dell’architettura operativa di FEWS.

Improvement of The Driver Simulator Control and Comparison Between Driver-Road-Vehicle Interaction in Real and Simulated Environment

The present doctoral thesis discusses the ways to improve the performance of driving simulator, provide objective measures for the road safety evaluation methodology based on driver’s behavior and response and investigates the drivers' adaptation to the driving assistant systems. The activities are divided into two macro areas; the driving simulation studies and on-road experiments. During the driving simulation experimentation, the classical motion cueing algorithm with logarithmic scale was implemented in the 2DOF motion cueing simulator and the motion cues were found desirable by the participants. In addition, it found out that motion stimuli could change the behaviour of the drivers in terms of depth/distance perception. During the on-road experimentations, The driver gaze behaviour was investigated to find the objective measures on the visibility of the road signs and reaction time of the drivers. The sensor infusion and the vehicle monitoring instruments were found useful for an objective assessment of the pavement condition and the drivers’ performance. In the last chapter of the thesis, the safety assessment during the use of level 1 automated driving “ACC” is discussed with the simulator and on-road experiment. The drivers’ visual behaviour was investigated in both studies with innovative classification method to find the epochs of the distraction of the drivers. The behavioural adaptation to ACC showed that drivers may divert their attention away from the driving task to engage in secondary, non-driving-related tasks.

Photocatalytic production of chemicals and hydrogen from biomass

In this work, with the aim to tackle several approaches towards sustainable chemistry, two reactions were studied: aerobic photo-oxidation of biomass derived 5-hydroxymethyl-2-furfural (HMF), and anaerobic photo-reforming of glycerol known as a by-product in biodiesel industry, towards production of chemicals and hydrogen. Solar-assisted reactions were performed by means of heterogeneous photocatalysis, in mild conditions such as atmospheric pressure, room temperature and water as a benign solvent. Titanium dioxide (lab-synthesized and commercial) was used as a photo-active catalyst, which surface was modified by introducing different metal (e.g. Au, Au-Cu, Pt) and metal oxide (e.g. NiO) nanoparticles. The prepared materials were characterized by XRD, DRS, BET, TEM, SEM, RAMAN and other techniques. The influence of the support, the size and type of the deposited metal and metal oxide nanoparticles on the photo-catalytic transformation of HMF and glycerol was evaluated. In the case of HMF, the influence of the base addition and the oxygen content on the reaction selectivity was also studied. The effect of the crystalline phase composition and morphology of TiO2 in the glycerol photo-reforming reaction was assessed as well. The surface of the synthesized TiO2 nano-powders was investigated by means of Surface Organometallic Chemistry (SOMC) approach. In particular, the surface was characterized by chemical titration and DRIFT techniques. Furthermore, the SOMC concept allowed preparing of well-dispersed Pt nanoparticles on the TiO2 surface. The photo-catalytic activity of this sample in the glycerol photo-reforming process was tested and compared to that of other Pt-containing catalysts prepared by conventional technics. In view of avoiding the agglomeration and sedimentation of suspended titania powders in water media, thick films of synthesized and commercial TiO2 were deposited on a conductive substrate using screen-printing technique. The prepared electrodes were characterized by profilometry, SEM, XRD, optical, electrochemical and photo-electrochemical methods.

Numerical modelling and structural optimization of multifunctional maritime structures aimed to protect harbours and produce energy

The main objective of this PhD thesis is to optimize a specific multifunctional maritime structure for harbour protection and energy production, named Overtopping Breakwater for Energy Conversion (OBREC), developed by the team of the University of Campania. This device is provided with a sloping plate followed by a unique reservoir, which is linked with the machine room (where the energy conversion occurs) by means of a pipe passing through the crown wall, provided with a parapet on top of it. Therefore, the potential energy of the overtopping waves, collected inside the reservoir located above the still water level, is then converted by means of low – head turbines. In order to improve the understanding of the wave – structure interactions with OBREC, several methodologies have been used and combined together: i. analysis of recent experimental campaigns on wave overtopping discharges and pressures at the crown wall on small – scale OBREC cross sections, carried out in other laboratories by the team of the University of Campania; ii. new experiments on cross sections similar to the OBREC device, planned and carried out in the hydraulic lab at the University of Bologna in the framework of this PhD work; iii. numerical modelling with a 1 – phase incompressible fluid model IH – 2VOF, developed by the University of Cantabria, and with a 2 – phase incompressible fluid model OpenFOAM, both available from the literature; iv. numerical modelling with a new 2 – phase compressible fluid model developed in the OpenFOAM environment within this PhD work; v. analysis of the data gained from the monitoring of the OBREC prototype installation.

Seismic fragility assessment of unreiforced masonry aggregate buildings

Aggregate masonry buildings have been generated over the years, allowing the interaction of different aggregated structural units under seismic action. The first part of this work is focused on the seismic vulnerability and fragility assessment of clay brick masonry buildings, sited in Bologna (Italy), with reference, at first, to single isolated structural units, by means of the Response Surface statistical method, taking into account some variabilities and uncertainties involved in the problem. The seismic action was defined by means of a group of selected registered accelerograms, in order to analyse the effect of the variability of the earthquakes. Identical and different structural units chosen by the Response Surface generated simulations are then aggregated in row, in order to compare the collapse PGA referred to the isolated structural unit and the one referred to the aggregate structure. The second part is focused on the seismic vulnerability and fragility assessment of stone masonry structures, sited in Seixal (Portugal), applying a methodology similar to that used for the buildings sited in Bologna. Since the availability of several information, the analyses involved the assessment of the most prevalent structural typologies in the area, considering the variability of a set of structural and geometrical parameters. The results highlighted the importance of the statistic procedures as method able to consider the variabilities and the uncertainties involved in the problem of the fragility of unreinforced masonry structures, in absence of accurate investigations on the structural typologies, as in the Seixal case study. Furthermore, it was showed that the structural units along the unreinforced clay brick or stone masonry aggregates cannot be analysed as isolated, as they are affected by the effect of the aggregation with adjacent structural units, according to the different directions of the seismic action considered and to their different position along the row aggregate.

Design of biobased additives for tuning the properties of biopolymers

This work mainly arises from the necessity to support the rapid introduction of different biobased polymers that the industrial sector has been facing lately. Indeed, while considerable efforts are being made to find environmentally and economically sustainable materials, less attention is paid to their need to be properly compounded to fulfil increasingly rigorous technical and quality requirements. Therefore, there is a strong demand for the development of a novel generation of compatible additives able to improve the properties of biobased polymers while respecting sustainability. With this in mind, a new class of biobased plasticizers is herein proposed. Five different ketal-diesters were selectively synthesized starting from levulinic acid, a promising renewable chemical platform. These molecules were added to poly(vinyl chloride) as model polymer to test their plasticizing effectiveness. Complete morphological, thermal and viscoelastic characterizations showed a clear correlation between the structural features of the ketal-esters and the properties of the material. In addition, no significant leaching was found in both hydrophilic and lipophilic environments. Importantly, the proposed ketal-diesters performed comparably and, in some cases, even better than commercial plasticizers. The same molecules were then added to bacterial poly(3-hydroxybutyrate), a semicrystalline polyester characterized by poor thermal and mechanical properties. Morphology assessments showed no phase separation and the plasticizing effectiveness was confirmed by thermal and viscoelastic analyses, while leaching tests showed low extraction values. Readily usable fractions with controlled structure and tailored properties were obtained from highly heterogeneous industrial grade Kraft lignin. These fractions were then added to poly(vinyl alcohol). Promising preliminary results in terms of compatibility were achieved, with thermograms showing only one glass transition temperature. Finally, a fully biobased glycerol-trilevulinate was successfully synthesized by means of a mild and solvent-free route. Its plasticizing effectiveness was evaluated on poly(vinyl chloride), showing a significant decrease of the glass transition temperature of the material.

Development of methodologies supporting the sustainable and safe integration of offshore conventional and renewable energy production

Against a backdrop of rapidly increasing worldwide population and growing energy demand, the development of renewable energy technologies has become of primary importance in the effort to reduce greenhouse gas emissions. However, it is often technically and economically infeasible to transport discontinuous renewable electricity for long distances to the shore. Another shortcoming of non-programmable renewable power is its integration into the onshore grid without affecting the dispatching process. On the other hand, the offshore oil & gas industry is striving to reduce overall carbon footprint from onsite power generators and limiting large expenses associated to carrying electricity from remote offshore facilities. Furthermore, the increased complexity and expansion towards challenging areas of offshore hydrocarbons operations call for higher attention to safety and environmental protection issues from major accident hazards. Innovative hybrid energy systems, as Power-to-Gas (P2G), Power-to-Liquid (P2L) and Gas-to-Power (G2P) options, implemented at offshore locations, would offer the opportunity to overcome challenges of both renewable and oil & gas sectors. This study aims at the development of systematic methodologies based on proper sustainability and safety performance indicators supporting the choice of P2G, P2L and G2P hybrid energy options for offshore green projects in early design phases. An in-depth analysis of the different offshore hybrid strategies was performed. The literature reviews on existing methods proposing metrics to assess sustainability of hybrid energy systems, inherent safety of process routes in conceptual design stage and environmental protection of installations from oil and chemical accidental spills were carried out. To fill the gaps, a suite of specific decision-making methodologies was developed, based on representative multi-criteria indicators addressing technical, economic, environmental and societal aspects of alternative options. A set of five case-studies was defined, covering different offshore scenarios of concern, to provide an assessment of the effectiveness and value of the developed tools.

System innovation and life cycle thinking in packaging value chain: the circularity of plastics.

Compared to other, plastic materials have registered a strong acceleration in production and consumption during the last years. Despite the existence of waste management systems, plastic_based materials are still a pervasive presence in the environment, with negative consequences on marine ecosystem and human health. The recycling is still challenging due to the growing complexity of product design, the so-called overpackaging, the insufficient and inadequate recycling infrastructure, the weak market of recycled plastics and the high cost of waste treatment and disposal. The Circular economy package, the European Strategy for plastics in a circular economy and the recent European Green Deal include very ambitious programmes to rethink the entire plastic value chain. As regards packaging, all plastic packaging will have to be 100% recyclable (or reusable) and 55% recycled by 2030. Regions are consequently called upon to set up a robust plan able to fit the European objectives. It takes on greater importance in Emilia Romagna where the Packaging valley is located. This thesis supports the definition of a strategy aimed to establish an after-use plastics economy in the region. The PhD work has set the basis and the instruments to establish the so-called Circularity Strategy with the aim to turn about 92.000t of plastic waste into profitable secondary resources. System innovation, life cycle thinking and participative backcasting method have allowed to deeply analyse the current system, orientate the problem and explore sustainable solutions through a broad stakeholder participation. A material flow analysis, accompanied by a barrier analysis, has supported the identification of the gaps between the present situation and the 2030 scenario. Eco-design for and from recycling (and a mass _based recycling rate (based on the effective amount of plastic wastes turned into secondary plastics), valorized by a value_based indicator, are the key-points of the action plan.

Experimental and numerical investigation on short and long term performance of macro-synthetic fibre reinforced concrete materials

Fibre Reinforced Concretes are innovative composite materials whose applications are growing considerably nowadays. Being composite materials, their performance depends on the mechanical properties of both components, fibre and matrix and, above all, on the interface. The variables to account for the mechanical characterization of the material, could be proper of the material itself, i.e. fibre and concrete type, or external factors, i.e. environmental conditions. The first part of the research presented is focused on the experimental and numerical characterization of the interface properties and short term response of fibre reinforced concretes with macro-synthetic fibers. The experimental database produced represents the starting point for numerical models calibration and validation with two principal purposes: the calibration of a local constitutive law and calibration and validation of a model predictive of the whole material response. In the perspective of the design of sustainable admixtures, the optimization of the matrix of cement-based fibre reinforced composites is realized with partial substitution of the cement amount. In the second part of the research, the effect of time dependent phenomena on MSFRCs response is studied. An extended experimental campaign of creep tests is performed analysing the effect of time and temperature variations in different loading conditions. On the results achieved, a numerical model able to account for the viscoelastic nature of both concrete and reinforcement, together with the environmental conditions, is calibrated with the LDPM theory. Different type of regression models are also elaborated correlating the mechanical properties investigated, bond strength and residual flexural behaviour, regarding the short term analysis and creep coefficient on time, for the time dependent behaviour, with the variable investigated. The experimental studies carried out emphasize the several aspects influencing the material mechanical performance allowing also the identification of those properties that the numerical approach should consider in order to be reliable.

How to cope with air transport disruptions: airport airside resilience and vulnerability

The efficiency of airport airside operations is often compromised by unplanned disruptive events of different kinds, such as bad weather, strikes or technical failures, which negatively influence the punctuality and regularity of operations, causing serious delays and unexpected congestion. They may provoke important impacts and economic losses on passengers, airlines and airport operators, and consequences may propagate in the air network throughout different airports. In order to identify strategies to cope with such events and minimize their impacts, it is crucial to understand how disruptive events affect airports’ performance. The research field related with the risk of severe air transport network disruptions and their impact on society is related to the concepts of vulnerability and resilience. The main objective of this project is to provide a framework that allows to evaluate performance losses and consequences due to unexpected disruptions affecting airport airside operations, supporting the development of a methodology for estimating vulnerability and resilience indicators for airport airside operations. The methodology proposed comprises three phases. In the first phase, airside operations are modelled in both the baseline and disrupted scenarios. The model includes all main airside processes and takes into consideration the uncertainties and dynamics of the system. In the second phase, the model is implemented by using a generic simulation software, AnyLogic. Vulnerability is evaluated by taking into consideration the costs related to flight delays, cancellations and diversions; resilience is determined as a function of the loss of capacity during the entire period of disruption. In the third phase, a Bayesian Network is built in which uncertain variables refer to airport characteristics and disruption type. The Bayesian Network expresses the conditional dependence among these variables and allows to predict the impacts of disruptions on an airside system, determining the elements which influence the system resilience the most.

Synthesis, Modification and Characterization of Polymeric Membranes for CO2 Separation

This doctorate focused on the development of dense polymeric membranes for carbon capture, mostly in post combustion applications, and for natural gas sweetening. The work was supported by the European Project NANOMEMC2 funded under H2020 program. Different materials have been investigated, that rely on two main transport mechanisms: the solution-diffusion and the facilitated transport. In both cases, proper nano-fillers have been added to the matrix, in order to boost the mechanical and permselective properties of the membranes. Facilitated transport membranes were based on the use of was polyvinylamine (PVAm), as main matrix with fixed-site carriers, and L-Arginine as mobile carrier; the filler, used mostly as reinforcer, was carboxymethylated nanocellulose (cNFC). Humid test showed interesting results, and especially the blend made of PVAm/cNFC/Arg in weight ratio 27,5/27,5/45 crossed the Robeson CO2/N2 upper bound, representing current state of the art membranes, with a CO2 permeability of 271 Barrer and CO2/N2 selectivity of 70. Solution diffusion membranes were based on Pebax®2533 matrix which was added with three different graphene oxide (GO)-based materials, namely pristine GO, Porous Graphene Oxide (PGO) and a GO functionalized with polyetheramine (PEAGO). All of them provided a modest but clear increment of permeability of the Pebax matrix, from plus 2% (GO) to plus 8% (PGO), with no change in selectivity. The gas tested with this type of composites were CO2 and N2, for Post combustion capture applications. Pebax®2533 was also chemically modified, obtaining the product called “Benzoyl-P2533”, that was fully characterized, and tested in term of permeation using five gas: CO2, N2, CH4, O2, and He. Modified material showed an increment of the overall permeability of the material of a fair 10% for all gases tested, apart from helium, that increased of almost 50%.

New bio-based polymers: from synthesis to characterization

The environmental problems caused by human activity are one of the main themes of debate of the last Century. As regard plastics, the use of non-renewable sources together with the accumulation of waste in natural habitats are causing serious pollution problems. For this reason, a continuously growing interest is recorded around sustainable materials, potential candidate for the replacement of traditional recalcitrant plastics. Promising results have been obtained with biopolymers, in particular with the class of biopolyesters. Their potential biodegradability and biobased nature is particularly interesting mainly for food packaging, where the multilayer systems normally used and the contamination by organic matter create severe recycling limits. In this framework, the present research has been conducted with the aim of synthetizing, modifying and characterizing biopolymers for food packaging application. New bioplastics based on monomers derived from renewable resources were successfully synthetized by two-step melt polycondensation and chain extension reaction following the “Green chemistry” principles. Moreover, well-known biopolyesters have been modified by blending or copolymerization, both resulting effective techniques to ad hoc tune the polymer final characteristics. The materials obtained have been processed and characterized from the chemical, structural, thermal and mechanical point of view; more specific characterizations as compostability tests, surface hydrophilicity film evaluation and barrier property measurements were conducted.

Novel membranes for hemodialysis application

The present work is focused on the synthesis and characterization of novel materials for hemodialysis applications. Cellulose acetate was chosen as base polymer for the preparation of porous Mixed Matrix Membrane adsorbers (MMMAs) and for the synthesis of hybrid ultrafiltration membranes. Hemodialysis is a renal replacement therapy used to eliminate,the waste products and excess fluids accumulating in the blood of people affected by an end stage renal disease. The main environmental drawback associated to it is the large water consumption. The MMMAs were prepared with the porpoise of eliminating waste metabolites (uremic toxins) from the spent dialysate solution, with the prospective limiting the consumption of water related to the process. Batch tests of MMMAs showed that the removal of uric acid is almost complete while the one of urea and creatinine is limited to a 20/30 %. The thinking behind the concept of MMMAs was aimed to develop a small a lab scale chromatographic cartridge to continuously remove uremic toxins from an aqueous feed solution. The cartridge was packed with MMMAs and tested with a mixture of toxins. Experiments results shown a promising removal capability of the system even if the necessity of a higher surface area to achieve better efficiency is denoted. The other important issue related to hemodialysis is the assessment of an overall mass transfer rates in hemodialyzers. The mass transfer correlations proposed in literature do not take into account the effect of permeation and are developed for turbulent flow regime. Therefore, hybrid cellulose acetate/Silica ultrafiltration membranes were prepared to characterize a surrogate system of an artificial kidney (AK) in terms of fluid mechanics and mass transfer. The effect of surface roughness and suction on the velocity profiles was determined and a new dimensionless mass transfer correlation accounting for permeation was developed.

Ultra-Low Temperature Partial Oxidation: Detailed Kinetics, Safety, and Environmental Issues

The innovation in several industrial sectors has been recently characterized by the need for reducing the operative temperature either for economic or environmental related aspects. Promising technological solutions require the acquisition of fundamental-based knowledge to produce safe and robust systems. In this sense, reactive systems often represent the bottleneck. For these reasons, this work was focused on the integration of chemical (i.e., detailed kinetic mechanism) and physical (i.e., computational fluid dynamics) models. A theoretical-based kinetic mechanism mimicking the behaviour of oxygenated fuels and their intermediates under oxidative conditions in a wide range of temperature and pressure was developed. Its validity was tested against experimental data collected in this work by using the heat flux burner, as well as measurements retrieved from the current literature. Besides, estimations deriving from existing models considered as the benchmark in the combustion field were compared with the newly generated mechanism. The latter was found to be the most accurate for the investigated conditions and fuels. Most influential species and reactions on the combustion of butyl acetate were identified. The corresponding thermodynamic parameter and rate coefficients were quantified through ab initio calculations. A reduced detailed kinetic mechanism was produced and implemented in an open-source computational fluid dynamics model to characterize pool fires caused by the accidental release of aviation fuel and liquefied natural gas, at first. Eventually, partial oxidation processes involving light alkenes were optimized following the quick, fair, and smoot (QFS) paradigm. The proposed procedure represents a comprehensive and multidisciplinary approach for the construction and validation of accurate models, allowing for the characterization of developing industrial sectors and techniques.