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La manifattura del cuoio e della calzatura nell'Italia comunale. Tecniche, struttura produttiva e organizzazione del lavoro
Get PDFIn epoca pre-industriale, il cuoio era uno dei materiali maggiormente utilizzati, tanto nel settore calzaturiero quanto nel settore militare o nei trasporti. Questa ricerca si propone di indagare principalmente due attività collegate a questo materiale, la manifattura conciaria e la produzione calzaturiera, e la loro organizzazione tra XIII e XV secolo.
La tesi si articola in cinque capitoli volti a esplorare tutti gli attori e i fattori coinvolti nella produzione di cuoio attraverso l'analisi di documentazione d'archivio: testi legislativi, documentazione giudiziaria, amministrativa e fiscale, affiancata da registri di conti privati e atti notarili. La scelta di affrontare fonti di natura differente ha richiesto la presa in esame di diversi centri urbani, la scelta è dunque ricaduta sulle città di Arezzo, Bologna e Rimini, mantenendo sempre aperto il confronto con altre realtà dell'Italia centro-settentrionale.
Il primo aspetto preso in esame è la relazione tra attività produttive e governi cittadini che erano responsabili della gestione di un alto numero di lavoratori che si occupavano di un'attività che aveva un forte impatto sul territorio, tanto in termini di sfruttamento delle risorse (idriche, minerali, agricole e dell'allevamento) quanto in termini di inquinamento.
Una volta individuate le materie prime necessarie per la produzione, e le politiche attivate per il suo reperimento, si è svolta un ricostruzione del settore innanzitutto dal punto di vista tecnico, per identificare il processo produttivo e le sue caratteristiche. L'analisi delle fasi di lavorazione che permettevano la trasformazione della pelle in cuoio e poi la produzione di calzature, ha evidenziato innanzitutto alcuni fattori che ne influenzavano l'organizzazione.
Conseguentemente ci si è dunque interrogati sulle modalità di organizzazione del settore e di divisione del lavoro e si è scelto di indagare innanzitutto come le corporazioni intervenivano e si inserivano in tale ciclo produttivo. Prendendo come esempio il caso di Bologna si è evidenziato il percorso di strutturazione e gerarchizzazione delle corporazioni del settore, che aveva progressivamente portato a una più netta divisione del ciclo produttivo, e che parallelamente concedeva maggiori margini d'azione ad alcuni singoli operatori economici. I soggetti maggiormente influenzati da tali modifiche istituzionali erano infatti gli imprenditori e i lavoratori del settore che nel corso del tardo Medioevo ebbero la possibilità di migliorare il proprio status, grazie al coinvolgimento, tanto economico quanto politico, nelle corporazioni del cuoio.
Infine, una sezione è stata dedicata all'analisi degli oggetti in cuoio, delle loro caratteristiche tecniche ma soprattutto del loro valore, sia simbolico che di mercato.
Lo studio di oggetti, persone e istituzioni coinvolte nel complesso settore del cuoio si propone di inserire innanzitutto un ulteriore tassello nella ricostruzione delle attività economiche, commerciali e manifatturiere, e nella ridefinizione delle componenti della società urbana dellâItalia comunale. In secondo luogo, l'analisi di diversi centri urbani ha consentito di evidenziare alcuni modelli di organizzazione e la loro evoluzione nel corso degli ultimi secoli del Medioevo
Exploring Multi-Modal and Structured Representation Learning for Visual Image and Video Understanding
Get PDFAs the explosive growth of the visual data, it is particularly important to develop intelligent visual understanding techniques for dealing with a large amount of data. Many efforts have been made in recent years to build highly effective and large-scale visual processing algorithms and systems. One of the core aspects in the research line is how to learn robust representations to better describe the data. In this thesis we study the problem of visual image and video understanding and specifically, we address the problem via designing and implementing novel multi-modal and structured representation learning approaches, both of which are fundamental research hot-spots in machine learning. Multi-modal representation learning involves relating information from multiple input sources, and the structured representation learning works on exploring rich structural information hidden in the data for robust feature learning. We investigate both the shallow representation learning frameworks such as dictionary learning and the deep representation learning frameworks such as deep neural networks, and present different modules devised in our works, consisting of cross-paced representation learning, cross-modal feature learning and transferring, multi-scale structured prediction and fusion, multi-modal prediction and distillation. These techniques are further applied in various visual understanding topics, i.e. sketch-based-image retrieval (SBIR), video pedestrian detection, monocular depth estimation and scene parsing, showing superior performance
Enabling access to and exploration of information graphs
Get PDFExploratory search is the new frontier of information consumption as it goes well beyond simple \emph{lookups}. Information repositories are ubiquitous and grow larger every day, and automated search systems help users find information in such collections. To extract knowledge from these repositories, the common ``query lookup'' retrieval paradigm accepts a set of specifications (the query) that describes the objects of interest and then collects such objects. Yet, the query lookup retrieval paradigms commonly in use are no more sufficient to support complex information needs, as they can only provide candidate starting points, but do not help the user in expanding their knowledge. To ease access and consumption of rich information repositories, we address the crucial problem of data exploration. Exploratory tasks match the natural need for finding answers to open-ended information needs within an unfamiliar environment. In particular, in this dissertation, we focus on enabling access to and exploration of rich information graphs. Within businesses, organizations, and among researchers, data is produced in many forms, large volumes, and different contexts. As a consequence of this heterogeneity, many applications find more useful modelling their datasets with the graph model, where information is represented with entities (nodes) and relationships (edges). Those are the data graphs, the graph databases, the knowledge graphs, or more generally information graphs. The richness of their schema and of their content makes it challenging for users to express appropriate queries and retrieve the desired results. Hence, to allow an effective exploration of a graph, we require: (i) an expressive \emph{query paradigm}, (ii) an intuitive \emph{query mechanism}, and (iii) an appropriate \emph{storage and query processing system}. In this work, we address these three requirements. An exploratory query should be simple enough to avoid complicate declarative languages (such as SQL or SPARQL), and at the same time, it should retain the flexibility and expressiveness of such languages. For this reason, with respect to the query paradigm, we introduce the notion of \emph{exemplar queries} and propose extensions to handle multiple incomplete examples. An exemplar query is a query method in which the user, or the analyst, circumvents query languages by using examples as input. In particular, the solution we design allows flexible matching in the case of incomplete or partially specified examples. Moreover, to enable this query paradigm, there is the need for interactive systems that implement an incremental query-constructions mechanism and interactive explorations. To address this need, we study algorithms and implementations based on pseudo-relevance feedback for \emph{exemplar query suggestion}, along with an in-depth study of their effectiveness. Finally, as there exist many graph databases, high heterogeneity can be observed in the functionalities and performances of these systems. We provide an exhaustive evaluation methodology and a comprehensive study of the existing systems that allow to understand their capabilities and limitations. In particular, we design a novel micro-benchmarking framework for the assessment of the functionalities of some graph databases among the most prominent in the area and provide detailed insights on their performance
On the Necessity of Complex Numbers in Quantum Mechanics
Get PDFIn principle, the lattice of elementary propositions of a generic quantum system admits a representation in real, complex or quaternionic Hilbert spaces as established by Solèr’s theorem (1995) closing a long standing problem that can be traced back to von Neumann’s mathematical formulation of quantum mechanics. However up to now there are no examples of quantum systems described in Hilbert spaces whose scalar field is different from the set of complex numbers. We show that elementary relativistic systems cannot be described by irreducible strongly-continuous unitary representations of SL(2, C) on real or quaternionic Hilbert spaces as a consequence of some peculiarity of the generators related with the theory of polar decomposition of operators. Indeed such a ”naive” attempt leads necessarily to an equivalent formulation on a complex Hilbert space. Although this conclusion seems to give a definitive answer to the real/quaternionic-quantum-mechanics issue, it lacks consistency since it does not derive from more general physical hypotheses as the complex one does. Trying a more solid approach, in both situations we end up with three possibilities: an equivalent description in terms of a Wigner unitary representation in a real, complex or quaternionic Hilbert space. At this point the ”naive” result turns out to be a definitely important technical lemma, for it forbids the two extreme possibilities.
In conclusion, the real/quaternionic theory is actually complex. This improved approach is based upon the concept of von Neumann algebra of observables. Unfortunately, while
there exists a thorough literature about these algebras on real and complex Hilbert spaces, an analysis on the notion of von Neumann algebra over a quaternionic Hilbert space is
completely absent to our knowledge. There are several issues in trying to define such a mathematical object, first of all the inability to construct linear combination of operators
with quaternionic coeffients. Restricting ourselves to unital real *-algebras of operators we are able to prove the von Neumann Double Commutant Theorem also on quaternionc
Hilbert spaces. Clearly, this property turns out to be crucial
Advanced classification methods for UAV imagery
Get PDFThe rapid technological advancement manifested lately in the remote sensing acquisition platforms has triggered many benefits in favor of automated territory control and monitoring. In particular, unmanned aerial vehicles (UAVs) technology has drawn a lot of attention, providing an efficient solution especially in real-time applications. This is mainly motivated by their capacity to collect extremely high resolution (EHR) data over inaccessible areas and limited coverage zones, thanks to their small size and rapidly deployable flight capability, notwithstanding their ease of use and affordability. The very high level of details of the data acquired via UAVs, however, in order to be properly availed, requires further treatment through suitable image processing and analysis approaches.
In this respect, the proposed methodological contributions in this thesis include: i) a complete processing chain which assists the Avalanche Search and Rescue (SAR) operations by scanning the UAV acquired images over the avalanche debris in order to detect victims buried under snow and their related objects in real time; ii) two multilabel deep learning strategies for coarsely describing extremely high resolution images in urban scenarios; iii) a novel multilabel conditional random fields classification framework that exploits simultaneously spatial contextual information and cross-correlation between labels; iv) a novel spatial and structured support vector machine for multilabel image classification by adding to the cost function of the structured support vector machine a term that enhances spatial smoothness within a one-step process. Conducted experiments on real UAV images are reported and discussed alongside suggestions for potential future improvements and research lines
Computational Sensory Analysis of Creative Language
No full textSensory information in language enables us to share perceptual experiences and create a common understanding of the world around us. Especially in the creative language, which reveals itself in many forms, such as figurative language, persuasive or effective language, sensory factors impose a leveraging effect into semantic meaning by its expressive power. Although in the last decade, the studies focusing on the perceptual aspects of language have been thriving, automatic creative language analysis still suffers from the lack of perceptual grounding with its characteristics of vivid, non-literal and complex semantics.
In this thesis, we propose the exploitation of the association between human senses and words as an external device to improve the computational linguistic models focusing on creative language. First, we present that sensory information reserved in the word meaning is obtainable by a distributional strategy over language. Second, we show that properly encoded sensory cues can enhance the automatic identification of figurative language. Finally, we argue that the exploitation of sensory information residing in linguistic modality in combination with the information coming from the perceptual modalities reinforces the computational assessment of multimodal creativity.
We present a large scale sensory lexicon generation approach followed by its utilization in two main computational creativity experiments to confirm our arguments: 1) phrase-level and word-level metaphor identification in existing metaphor corpora; 2) creativity appreciation assessment in multimodal advertising prints incorporating the linguistic and visual modalities. The findings of the experiments show that sensory information is an invaluable indication of the creative aspect of the language and makes a significant contribution to the state of the art creative language analysis systems
Optical biosensors for mycotoxin detection in milk
Get PDFOptical biosensors, and in particular label-free optical biosensors have become one of the most active and attractive fields within the biosensing devices. The portability and the possibility to set free from the laboratory settings gave a new hint for integrated photonic biosensors development and use in numerous applications. Integrated photonic sensors have shown very promising results, and in particular, devices like WGM resonators and interferometers are showing high sensitivities and miniaturization abilities, which allow the realization of an integrated complete lab-on-chip device.
The main goal of this thesis is the development of an optical biosensor for the fast and comprehensive detection of carcinogenic Aflatoxin M1 (AFM1) mycotoxin. The acceptable maximum level of AFM1 in milk according to European Union regulations is 50 ng/L equivalent to 152 pM for the adults and 25 ng/L equivalent to 76 pM for the infants, respectively.
Within a European Project named SYMPHONY, we develop an integrated silicon-photonic biosensor based on the optical microring resonators (MRR) and the asymmetric Mach-Zehnder Interferometers (aMZI). The sensing is performed by measuring the resonance wavelength shift in the MRR transmission or the phase shift of aMZI caused by the binding of the analyte to the ligand immobilized on the sensor surface.
The experimental characterization of the bulk refractometric sensing of the devices is performed in a continuous flow. This characterization assesses the high resolution of both device types, which are able to resolve variations in the refractive index of the liquids with a limit of detection down to 10E-6 refractive index units (RIU).
Furthermore, the SYMPHONY sensor optimization based on the Fab' and DNA-aptamer functionalization strategies is realized. It is therefore demonstrated, that the Fab' functionalization strategy provides more reproducible results with respect to the DNA-aptamer one. However, for both strategies, the specificity of the sensor functionalization to detect AFM1 molecules is achieved with respect to non-specific Ochratoxin molecules at high concentrations.
In the final stage of the SYMPHONY project, the Fab'-based functionalized aMZI sensor is tested with real milk samples (eluates) prepared in the SYMPHONY system that consists of the three main modules: the defatting module, the concentrator module and the sensor module. The system calibration yields the minimum concentration of AFM1 at 40 pM to be detectable.
The detection of the ligand-analyte binding in real-time enabled the study of the kinetics of the binding reaction, and we measured for the first time the kinetic rate constants of the Fab'-AFM1 interaction with our sensors.
Finally, a MRR based affinity biosensor is developed dedicated to the biotinylated BSA - anti-biotin binding study. An affinity constant of 10E6 1/M is measured. The sensor is successfully regenerated up to eight times by applying a longer incubation period
Behavioral Economics and Health: Nudging for our own good
Get PDFEach of us is made up of the decisions that we make. The rich tapestry of our lives is constructed from the hundreds of thousands of decisions that have led us to this very moment. If each of us were endowed with perfect rationality, our optimal decision-making qualities might lead us down similar paths. But here we are, instead each of us on unique and sometime bumpy rides accentuated by our perfectly irrational choices. The goal of my research is to make sense of our faulty decision making in areas related to personal health by applying insights from the field of behavioral economics. I am not the only one searching for answers. It's an exciting time to be a behavioral economist in light of the relatively recent birth of the subfield, as a splinter off of the traditional economics cutting block. It is a moment of prolific research in a thriving field of economists seeking to understand how exactly we err in the decision-making process, and what precisely can be done to help us err less. The timing could not be better for addressing poor decision-making in the health field. Behavioral factors play a starring role in today's burgeoning health crises, considering that smoking and tobacco use, lack of physical activity, poor eating habits, excessive alcohol use, and medical treatment noncompliance contribute to many of today's most prevalent health problems. In this doctoral thesis, I consider first and foremost the foundations of behavioral economics and its arrival from notions of bounded rationality and Prospect Theory, and what tools it offers to address pressing health issues. In the first chapter, I also consider the innovations in applications of behavioral economics to the most persistent health issues. In the following chapters, I offer new research (performed in collaboration with my coauthors) that applies concepts of behavioral economics to enhance decision making in two contexts. The role of information provision and quality is considered in light of parental decision making in the setting of childhood vaccines. Then I present the results of HealthyMe, an intensive collaborative effort involving experimental testing of an intervention to encourage active travel by foot and on bicycle using participants' cellphone to both record active travel and deliver nudge and feedback messages through a specially developed cellphone app
The project-based method for a competence-based approach: teaching computer science in Italian secondary schools
Get PDFThe competence-based approach to education has been found to be effective for teaching. Some countries have adopted it and subsequently reshaped the school system accordingly. Introduced in Italian secondary schools in 2010 by the Ministry for Education, the competence-based approach has only been partially adopted in the classes. Our research aims at discovering solutions to support the adoption of this approach for teachers in Italian secondary schools. A two steps approach has been investigated: 1) inclusion of teachers in the process of competence definition, and 2) support of teachers activity during student projects. The study focuses on computer science teachers, who often teach using the student projects. A software system for a participated definition of competences has been set up. A training course has been designed and implemented. Some student projects have been studied through teacher and student observation in the classroom and in laboratory. The results indicate a weak commitment on the part of teachers towards the competence-based approach. At the same time, exploiting students projects towards the project-based learning method encourages teachers to adopt a competence-based approach, provided the projects are carefully designed and effectively managed
Biomorphodynamics of river bars in channelized, hydropower-regulated rivers
Get PDFOver the past 200 years, rivers in industrialized countries have been significantly altered by human interventions such as channelization, hydropower development, and sediment mining causing observable biogeomorphological changes. In the European Alpine region, many large rivers have been impounded and channelized, yet few studies have conducted in-depth research on the temporal patterns of the causes and trajectories of these biogeomorphological responses, in comparison to rivers that can adjust their planform. Moreover, it is well-known that within channelized rivers alternating bars may appear due to an instability of the riverbed, but the development and influence of vegetation on such bars, its feedbacks on the morphodynamics of the bars and the degree to which these mutual interaction processes responds to anthropic stressors related to alterations in the flow and sediment supply regimes has received little attention.
The present research aims to disentangle the mechanisms that may determine dramatically diverging biogeomorphological trajectories in regulated Alpine rivers. It further intends to identify the underlying relations of the triad that connects vegetation – sediment – flow regime and its feedbacks in regulated, channelized, rivers with vegetated bars.
The methodology comprises an interdisciplinary approach which combines field and historical investigations with theoretical predictions, and integrates a variety of spatial and temporal scales and different levels of detail in characterising processes.
Two case studies in the Alpine region (the Isère river in southeast France and the Noce river in northeast Italy) were selected for a quantitative, historical analysis of the bio-morphological trajectories using remotely sensed data to investigate the apparent responses to human-induced modifications of natural processes. Both rivers have been heavily impacted, with a notable increase of human stressors since the mid-20th century which can be associated with the transition of both systems from an initial, stable dynamic state characterized by bars having only sparse colonizing vegetation with a frequent turnover to a new, apparently stable state characterised by reduced morphodynamics and an increased vegetation cover in recent decades.
The Isère river, which underwent a shift from unvegetated, migrating bars to vegetated, stable bars, was further explored with a hydromorphodynamic modelling approach to investigate historical changes in riparian vegetation recruitment and survival related to changes in the flow regime. The Windows of Opportunity model was successful at revealing temporal changes in recruitment conditions in response to flow regime alterations. Further results indicated a reduction in relevant high flow events that might be competent to induce large bar migration in the system. Alterations of the flow regime are assumed to have played a major role in vegetation encroachment directly by affecting vegetation recruitment through reduced flow disturbances and indirectly inducing modifications of bar morphodynamics.
Field observations of root development were also made on the Noce and Isère rivers, focusing on two species Salix alba and Phalaris arundinacea, with the aim of improving understanding of the role of roots on the presence and movement of vegetated bars. When comparing results from different sites, more predictable linear relationships between root properties and depth below the ground surface were associated with stronger flow regulation. Bar morphology (surface elevation or depth of sedimentation and sediment calibre) and flow regime were found to be the main drivers of root architecture. Furthermore, roots were found to have an important role in the stabilization of the bars with the ability to stabilise fine sediments trapped by the plant’s canopy during phases of bar aggradation.
To understand the current state of channelized Alpine rivers, which often show diverging biogeomorphic features, it is necessary to understand the underlying interactions between flow, sediment, and vegetation dynamics. Only through investigating the historical biomorphological evolution of rivers and the main drivers of that evolution it is possible to design measures that can be effective in rehabilitating desired ecosystem functions that have been markedly modified by those state transitions.
In summary, this study has provided novel, quantitative insights about the complexity of flow – vegetation – morphology interactions occurring in channelized river systems in relation to anthropogenic stressors causing alteration in their flow and sediment supply regimes. By integrating different approaches, this study has shown how these river systems can be highly sensitive to even small changes in the anthropogenic stressors, depending on the stage in their evolutionary trajectory, which is crucial to be detected to support the development of sustainable management strategies aimed at restoring or improving target riverine functions and processes