Shot peening is a cold-working surface treatment, basically consisting in pelting the surface of the to-be-treated component with a high number of small hard particles blown at relatively high velocity. This causes the plasticization of the surface layer of the substrate, and the generation of a compressive residual stress field beneath the component surface. The surface topology modification can be beneficial for coating adhesion, and the work hardening enhances the fretting resistance of components, but the most commonly appreciated advantage of the process is the increased fatigue resistance in the treated component, due to the compressive residual stress which inhibits the nucleation and propagation of fatigue cracks. In spite of its widespread use, the mechanisms underlying the shot peening process are not completely clear. Many process parameters are involved (material, dimension, velocity of the shots, coverage, substrate mechanical behavior) and their complex mutual interaction affects the success of the process as well as the jeopardizing of any beneficial effect due to the increased surface roughness. Experimental measurements are excessively expensive and time-costly to deal with the wide variability of the process parameters, and their feasibility is not always granted. The effect of shot peening is indeed particularly effective where geometrical details (e.g. notches or grooves) act as stress raisers and where the direct measurement of residual stresses is very difficult. Nonetheless, the knwoledge of the effects of the treatment in this crictical locations would be extremely useful for the quantitative assessment of the effect of shot peening and, ultimately, for the optimization fo the process as well as its complete integration in the design process. The implementation of the finite element method for the simulation of shot peening has been studied since many years. In this thesis the simulation of shot peening is studied, in order to progress towards a simulation approach to be used in the industrial practice. Specifically, the B120 micro shot peening treatment performed with micrometric ceramic beads is studied, which has proven to be very effective of aluminum alloys, such as the aeronautical grade Al7075-T651 alloy considered in this work. The simulation of shot peening on a flat surface is addressed at first. The nominal process parameters are used, to include stochastic variability of the shot dimensions and velocity. A MatLab routine based on the linearization of the impact dent dimension, on the shot dimension and velocity is used to assess the coverage level prior to the simulation and predict the number of shots to full coverage. To best reproduce the hardening phenomena of the substrate material under repeated impacts, the Lemaitre-Chaboche model is tuned on cyclic strain tests. Explicit dynamic finite element simulations are carried out and the statistical nature of the peening treatment is taken into account. The results extracted from the numerical analyses are the final surface roughness and residual stresses, which are compared to the experimentally measured values. A specific novel procedure is devised to account for the effect of surface roughness and radiation penetration in the in-depth residual stress profile. In addition, a static finite element model is devised to assess the concentration effect exerted by the increased surface roughness on an external stress. The simulation of shot peening on an edge is then addressed as a first step towards more complex geometries. Since the true peening conditions are not known in this locations, a synergistic discrete element - finite element method approach is chosen for the correct modelization of the process. A discrete element model of the peening process on a flat surface is used to tune the simulation on the nominal process parameters, i.e. mass flow rate and average shot velocity, and to assess the nozzle translational velocity. Discrete element simulations are used to simulate the process when the nozzle turns around the edge tip. To lower the computing cost, the process is linearized into static-nozzle simulations at different tilting angles. The number of impacting shots and their impact velocity distribution are used to set up the finite element simulations, from which the resulting residual stress field is obtained. In addition to the realistic simulation, two simplified simulation approaches for the practical industrial use are devised. The resulting residual stress fields are compared with the reference residual stress field computed using thermal fields in a finite element simulation, tuned with experimental XRD measurements. The effect of the dimension of the fillet on the edge tip is studied by modifying the finite element model of shot peening on an edge. 3 different fillet radii (up to 40 um) are considered, on the basis of experimental observations. The resulting residual stress field are compared to analyze the effect of the precise geometry of the substrate. Lastly, the simplified simulation approach devised in the case of the edge is used to simulate shot peening on the root of a notch. The resulting residual stress field is again compared to the reconstructed reference one.

The Reverse Engineering (RE) techniques and the Finite Element Modelling (FEM) are widely used tools in many scientific fields. They were firstly developed for the mechanics but in the last times became common for other disciplines. In the thesis these techniques are used for the customization of the wearable products. It is possible to observe that the geometry of whatever wearable product is fundamental for the comfort. In particular, starting from the need of wearable product it is possible to analyse the relative body part and to study the products most appropriate interface geometry to maximize the comfort. The related disciplines are biometrics, biomechanics and anthropometry. In the thesis four different non-contact RE techniques are taken into account: shape from stereo, shape from silhouette, shape from laser and range finding. The first instrument which has been developed is based on the multi stereo vision, focusing the attention to the data filtering and to the generation of the solid model represented by mesh. The second instrument is based on the model generation starting from the silhouette. These two techniques are compared to another laser instrument available on the market. The tolerance on the reconstruction give an error on the total length of the foot of about 2 mm. The tolerance is acceptable for the study of a footwear product anyway it is not sufficient for a scientific research. For this reason a fourth RE system based on range finding is studied. A lot of possible methods were analysed, the multifrequencies, belonging as Fringe Projection Profilometry (FPP) group, has been considered the best compromise between precision, accuracy and elaboration times. An instrument has been developed which in few seconds performs the reconstruction using common, cheap products such as a projector and a camera. The use of the aforementioned RE techniques allowed to adequately reconstruct the geometrical model of the foot, then the deformation of the foot is studied using a Finite Element Analysis (FEA). A model characterized by nearly 200000 elements has been developed. The deformations are congruent with literature data. Anyway, considering the complex validation process of the FE model, caused by the difficulties on measuring the real displacement of the foot under loading condition, a direct matching between the acquired geometry and the final shape of the wearable product has been preferred. A function, capable to analyse the fitting between foot and shoe, through a coefficient called comfort index has been developed.

La tesi analizza la costruzione sociale di bulli e vittime nei quotidiani italiani (La Repubblica e il Corriere della Sera) e inglesi (The Guardian and The Times) attraverso il metodo della classical content analysis. La prima parte riguarda la rewiew dei principali contributi teorici e analitici in merito a: costruzionismo sociale, costruzione sociale dei mass media della criminalità, devianza giovanile e fenomeno del bullismo. La seconda parte, interessa l’analisi dei profili di bulli e vittime nei quotidiani italiani e inglesi. L’ultima parte è relativa alla comparazione dei profili emersi sia nelle due fonti di informazione, sia con i profili contenuti nella letteratura scientifica sul bullismo. I risultati evidenziano come i quotidiani sia italiani, sia inglesi seguano modalità stereotipate di rappresentazione in linea con i contributi scientifici relativi alla costruzione sociale della devianza giovanile e della violenza nelle scuole. / The thesis analyses the social construction of bullies and victims in a sample of Italian (La Repubblica and Corriere della Sera) and English newspapers (The Guardian and the Times) applying a classical content analysis methodology. The main scientific literature on social constructionism, mass media and social construction of crime and youth crime is reviewed as well as the theoretical and research contributions on bullying. The images of bullies and victims delivered by Italian and English newspaper are further assessed and compared to the extant literature on the topic. Differences emerge both between newspapers and in regard to the theoretical and research contributions on bullies and victims, underlying specific stereotyped ways of newspapers to depict bullies and victims. Findings are consistent with previous research investigating the way mass media have depicted youth crime and in particular school violence.

The present doctoral thesis deals with the study and the analysis of large strain and high strain rate behavior of materials and components. Theoretical, experimental and computational aspects are taken into consideration. Particular reference is made to the modeling of metallic materials, although other kinds of materials are considered as well. The work may be divided into three main parts. The first part of the work consists in a critical review of the constitutive modeling of materials subjected to large strains and high to very high strain rates. Specific attention is paid to the opportunity of adopting so-called strength models and equations of state. Damage and failure modeling is discussed as well. In this part, specific interest is addressed to reviewing the so-called Johnson-Cook strength model, by critically highlighting its positive and negative aspects. One of the main tackled issue consists in a reasoned assessment of the various procedures adoptable in order to calibrate the parameters of the model. This phase is enriched and clarified by applying different calibration strategies to a real case, i.e. the evaluation of the model parameters for a structural steel. The consequences determined by each calibration approach are then carefully evaluated and compared. The second part of the work aims at introducing a new strength model, that consists in a generalization of the Johnson-Cook model. The motivations for the introduction of this model are first exposed and discussed. The features of the new strength model are then described. Afterwards, the various procedures adoptable for the determination of the material parameters are presented. The new strength model is then applied to a real case, i.e. a structural steel as above, and the results are compared to those obtained from the original Johnson-Cook model. Comparing to that, the obtained outcomes show that the new model displays a better capacity in reproducing experimental data. Results are discussed and commented. The third and final part of the work deals with an application of the studied topics to a real industrial case of interest. A device called perforating gun is analyzed in its structural problematics and critical aspects. This challenging application involves the modeling of several typologies of material, large strains, very high strain rate phenomena, high temperatures, explosions, hypervelocity impacts, damage, fracture and phase changes. In this regard, computational applications of the studied theories are presented and their outcomes are assessed and discussed. Several finite element techniques are considered. In particular, tridimensional Eulerian simulations are presented. The obtained results appear to be very promising in terms of the possibilities of a fruitful use in the design process of the device, in particular in order to achieve an optimization of its key features.

Le interfacce aptiche, ovvero le tecnologie che trasmettono delle sensazioni tattili digitalizzate, si stanno diffondendo in vari contesti sociali come telerobotica, comunicazione mobile, arte, videogiochi e cinema. Queste tecnologie stanno permettendo agli ingegneri di realizzare qualcosa mai fatto prima: la digitalizzazione del tatto (che ora può quindi essere registrato e mediatizzato). L’obbiettivo di questa tesi è di decostruire il tatto digitalizzato come un artefatto tecnologico socialmente costruito, il quale sta prendendo forma in un sistema di pratiche interrelate performate da attori in campi disparati della conoscenza. Questi attori si muovono all’interno e attorno ad una comunità di ingegneri apticisti. Adottando un approccio ispirato alla grounded theory, sono stati raccolti dati qualitativi attraverso interviste presso un campo etnografico multi-situato composto da laboratori europei e conferenze internazionali, in cui la conoscenza riguardo il tatto è collettivamente creata e condivisa. Due framework teorico-metodologici sono stati presi in considerazione: la tradizione dei Science and Technology Studies (STS) è stata scelta come principale guida metodologica; in seguito, l’intreccio tra pratiche sociali e tecnologie è stato approfondito attraverso una prospettiva practice-based tipica della cosiddetta ‘practice theory’. Al fine di cogliere il processo in corso di costruzione sociale e flessibilità che caratterizzano il tatto digitalizzato, lo studio si è concentrato sull'assenza di standardizzazione che caratterizza gli aspetti sia hardware che software di questa tecnologia emergente. Inoltre, è stata prestata attenzione alla distinzione controversa e scivolosa tra feedback tattile simbolico e realistico usata nel gergo degli apticisti. Infine, sono stati analizzati i diversi significati, o potenzialità d'uso, che gli intervistati attribuiscono a questa tecnologia. Questi significati si collegano a specifici immaginari sociotecnici geograficamente situati, ad ampi discorsi sociali riguardo l’innovazione tecnologica, e a diverse visioni riguardo le pratiche che possono beneficiare dell’implementazione di queste interfacce. / Devices that provide tactile feedback, called haptic interfaces, are spreading in various contexts such as tele-robotics, prosthetics, videogames, mobile communication, and arts. These technologies are allowing engineers to accomplish something never done before: the digitization of touch (which can now be stored and mediatized). This dissertation aims to deconstruct the digitized touch as a socially constructed technological product, emerging from a system of interrelated practices enacted by actors performing in disparate fields which revolve around the community of haptics engineers. Using a grounded-theory inspired approach, qualitative data were collected through interviews in a multi-sited ethnographic field consisting in European laboratories and international conferences, where knowledge about touch is collectively created and shared. Two theoretical-methodological frameworks have been taken into consideration: the tradition of Science and Technology Studies (STS) has been chosen as the main methodological guide; moreover, the interlacements between social practices and technology have been deepened through the adoption of a practice-based perspective proposed by different approaches in social sciences gathered under the umbrella term ‘practice theory’. In order to grasp the ongoing process of social construction and flexibility that characterize digitized touch, the study focused on the absence of standardization involving both hardware and software aspects of this emerging technology. Furthermore, attention has been paid to the controversial and slippery distinction between ‘symbolic’ and ‘realistic’ tactile feedback which is used in engineers’ jargon. Finally, the different meanings or potentialities of use, which respondents attributed to this technology, have been analysed. These meanings are connected to geographically located socio-technical imaginaries, to broad social discourses about technological innovation, and to different visions regarding the practices that can benefit from the implementation of these interfaces.

Il webcasting come strumento per la distribuzione di prodotti educational e la circolazione dei saperi. / The webcasting as a tool for the distribution of educational products and circulation of knowledge.

Cette recherche s’inscrit dans le cadre plus large d’une cotutelle de thèse en Sciences de l’Éducation entre les Universités de Nice et de Turin. Nous sommes partis du constat que l’organisation de l’éducation spécialisée en Europe est loin d’être homogène. Ainsi, en Italie, contrairement à la France, la formation en travail social est confiée aux universités. Depuis l’inscription de la formation française dans le cadre européen en 1989, la réorganisation des contenus de formation et la mise en conformité avec le reste de l’Europe a provoqué une révision profonde du modèle pédagogique de référence et de la conception même de la profession. À partir de cette étude comparative, notre thèse étudie l’impact de ce nouveau modèle de transmission et de reconnaissance des savoirs sur la professionnalisation des travailleurs sociaux, afin d’envisager comment le cadre européen agit à travers ses deux postulats : la transférabilité des savoirs et des compétences professionnelles. En partant d’un secteur spécifique comme celui de l’éducation spécialisée, notre thèse explore le double aspect de la formation – transférabilité des savoirs- et de la professionnalisation – transférabilité des compétences –afin de vérifier s’il est judicieux de parler d’une véritable "Europe des métiers du social". / This research is incorporated within the wider framework of a thesis in Educational Studies which was co-tutored by the University of Nice in France and the University of Turin in Italy. We started by observing that the organisation of specialised education in Europe is far from being homogeneous. Consequently, Social Work Education in Italy is entrusted to Universities, yet not in France. Since French education was incorporated within the European Framework in 1989, the re-organisation of the educational content and its compliance with the rest of Europe has led to a deep reviewing of both the pedagogical model of reference and the conception of the profession itself. Moving from this comparative study, our thesis analyses the impact of this new model of transmission and recognition of knowledge on the professionalization of social workers in order to understand how the European framework acts through the two following postulates : the transferability of knowledge and the transferability of professional expertises. Starting from the specific field of specialised education, our study explores the double aspect of education – knowledge transferability – and professionalization – expertises transferability – in order to verify whether it is wise to talk about a common “European approach to social work”. / Questa tesi in Scienze dell’Educazione ha visto la luce nell’ambito di una co-tutela tra l'Università di Nizza e l’Università di Torino. La premessa è che la professione dell’educatore in Europa è tutt’altro che omogenea. In Italia, sin dagli anni Novanta, la formazione degli educatori è affidata alle università e conserva una base disciplinare. In Francia, invece, essa é delegata alle scuole regionali ed é declinata in competenze. Inoltre, nel 2010 é stata attuata una profonda revisione del modello pedagogico in nome dell’adesione alle norme che regolano lo Spazio Europeo dell'Istruzione Superiore (SEIS). In questo quadro si colloca il nuovo modello di trasmissione e di riconoscimento dei saperi proposto dall’Europa, basato su due postulati : la trasferibilità delle conoscenze e delle competenze professionali. Partendo da un settore specifico come quello dell’educazione professionale, la ricerca si è proposta di esplorare il doppio aspetto della comparazione dei sistemi di formazione – trasferibilità delle conoscenze – e professionali – trasferibilità delle competenze – al fine di verificare se è possibile parlare di una "Europa dei mestieri del sociale".

Mobile assistive robotics can play a key role to improve the autonomy and lifestyle of patients. In this context, RoboEye project aims to support people affected by mobility problems that range from very impairing pathologies (like ALS, amyotrophic lateral sclerosis) to old age. Any severe motor disability is a condition that limits the capability of interacting with the environment, even the domestic one, caused by the loss of the control on our own mobility. Although these pathologies are relatively rare, the number of people affected by this disease are increasing during the years. The focus of this project is the restore of persons’ mobility using novel technologies based on the gaze on a power wheelchair designed to enable the user to move easily and autonomously inside his home. A novel and intuitive control system was designed to achieve such a goal, in which a non-invasive eye tracker, a monitor, and a 3D camera represent some of the core elements. The developed prototype integrates, on a standard power wheelchair, functionalities from the mobile robotics field, with the main benefit of providing to the user two driving options and comfortable navigation. The most intuitive, and direct, modality foresees the continuous control of the frontal and angular velocities of the wheelchair by gazing at different areas of the monitor. The second, semi-autonomous, enables the navigation toward a selected point in the environment by just pointing and activating the wished destination while the system autonomously plans and follows the trajectory that brings the wheelchair there. The main goal is the development of shared control, combining direct control by the user with the comfort of autonomous navigation based on augmented reality markers. A first evaluation has been performed on a real test bed where specific motion metrics are evaluated. The designs of the control structure and driving interfaces were tuned thanks to the testing of some volunteers, habitual users of standard power wheelchairs. The driving modalities, especially the semi-autonomous one, were modelled and qualified to verify their efficiency, reliability, and safety for domestic usage.

Prigioniero a Tripoli e falso sacerdote. Apostata e penitente. Supposto martire e, pertanto, candidato alla santità. È questo il ritratto di Alipio di S. Giuseppe che emerge dalle fonti agiografiche e dal cospicuo, e in gran parte inedito, corpus documentario, di cui il primo capitolo della tesi offre un’articolata ricognizione. La vicenda di questo frate agostiniano scalzo di origine palermitana – che ben si inserisce nel contesto mediterraneo dei secoli XVI-XVII, caratterizzato da un continuo e ampio rimescolamento di uomini, merci, appartenenze religiose e culturali, e di cui la guerra di corsa, con tutte le sue conseguenze, costituisce una delle dimensioni più rappresentative – fu anzitutto una vicenda di prigionia, conversione all’islam e successiva abiura, nonché di martirio, cui il religioso andò volontariamente incontro nel febbraio del 1645; di questi aspetti, delle modalità con cui il tragico fatto fu trasmesso dai missionari apostolici residenti a Tripoli e recepito all’interno dell’Ordine degli Agostiniani Scalzi, oltre che delle interessanti analogie con altri episodi di apostasia si parla nel secondo capitolo. Nel terzo capitolo, invece, si dà conto del ruolo di primo piano avuto dalla famiglia siciliana dei Tomasi nella promozione della causa di beatificazione di fra Alipio, avviata in seguito all’arrivo, nel 1653, delle sue reliquie sul litorale agrigentino e approdata, dopo le ordinariae inquisitiones del biennio 1654-1656, alla Congregazione dei Riti, che però espresse parere negativo sia nel 1658 sia sessant’anni più tardi. / Captive in Tripoli and false priest, apostate and penitent, alleged martyr and then candidate to sainthood. That is the portrait the first part of this work brought to light from the considerable documentary corpus about Alipio di San Giuseppe, mostly still unpublished. The human existence of this Augustinian Discalceate friar from Palermo – set in the XVI and XVII centuries, when in the Mediterranean mix of people, goods, religions, also privateering was a significant aspect – is a sequence of captivity, conversion to Islam and following abjuration, culminating in the martyrdom he deliberately chose in February 1645. This story, its narration made by the apostolic missionaries in Tripoli as wells as its understanding by the Augustinian Discalceate order are investigated in the second chapter and compared with similar episodes of abjuration. In the third part the relevant role played by the Sicilian family Tomasi in promoting the beatification proceedings of Alipio is explained; started after his relics were brought to the shore near Agrigento in 1653, the proceedings moved to the Congregatio Sacrorum Rituum after the ordinariae inquisitiones in 1654-1656, and there were denied first in 1658 and definitively 60 years later.