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Development of teaching-learning sequences on quantum physics for the Italian secondary school
In the past 15 years, quantum mechanics has been included in most secondary school
standards, including the Italian ones, but still in a rather marginal way. The conceptual complexity
of quantum mechanics is often a hurdle for students as well as for teachers; as a consequence, most
teachers and textbooks opt for narrative/historical approaches which, however, are not sufficient to
grasp the deepest conceptual aspects of quantum physics, nor to deal with its technological
applications. Teaching quantum physics in secondary school is therefore a challenge that calls for a
close collaboration between physics teachers and physics education researchers. The goal of this
work is to develop and test research-based teaching-learning sequences (TLS) based on the study of
relevant literature in physics education research and on a survey to be conducted with secondary
school teachers. More specifically, the thesis work will include the following phases. A review of
the literature on the teaching and learning of quantum mechanics, with particular reference to the
proposals developed in the Italian context. A survey with a sample of secondary school physics
teachers aimed at understanding the needs and difficulties of teaching quantum mechanics. On the
basis of the literature and of the results of the survey, development of a teaching-learning sequence
(TLS) on quantum mechanics for the fifth year of the Italian “liceo scientifico”. Testing and
evaluation of the TLS in a real classroom context
Incremental clustering of continuous perceptions
This thesis aims to develop a framework for the incremental clustering of
the perceptions ofan agent. The agent moves in a simulated environment and
collects data about its position and its surroundings, in particular the
egocentric images seen by its on-board camera. In this context, clustering
is useful to group together the perceptions of a same object, in particular
to recognize objects which have already been seen by the agent. This task
is performed with the aid of a neural network, pre-trained to recognize if
two perceptions are associated to a same object. In this thesis we analyze
the tuning and training performed for the neural network, the clustering
algorithm and its performance
Studio e progettazione di un intervento di rinnovo tecnologico di sottostazione elettrica (SSE) ferroviaria di conversione
L'elaborato fornisce lo studio di una ignota sottostazione elettrica ferroviaria di conversione per la trazione elettrica alla tensione di 3 kVcc, sottoposta ad un intervento di rinnovo tecnologico con finalità di risolvere i problemi emersi durante il suo esercizio attraverso un'analisi e una progettazione secondo le normative vigenti
Top-down processing of noisy and adversarial stimuli in deep generative models
This thesis studies the effect of adding a term usually neglected during
the training phase of energy-based models. It is called ``KL term'' because
of its dependence on Kullback-Leibler divergence, and it does not have a
significant impact on the training in terms of running time and
computational cost. I will initially present an analysis of its impact on training stability and some considerations relative to the general structure of the learning model. I will then study the denoising capabilities of the model by implementing top-down processes applied to different types of noisy input. Thirdly, to understand the quality of internal representations emerging in the hidden layers, I will apply a read-out classifier to the deepest hidden layer, calculating psychometric curves produced with different noise values. The final analysis will explore the model capability to resist to adversarial attacks using forward-backward iterations, also considering the spontaneous generative activity of the network by stimulating the read-out neurons relative to a specific class. Interestingly, results of this latter investigation are very encouraging for the MNIST dataset, suggesting that this type of energy-based models has potential to improve current defenses on adversarial attacks. However, for Cifar10 dataset it seems that more powerful computing hardware is needed to train models of larger sizes
Caratterizzazione delle sfere metriche nello spazio iperbolico complesso
Lo scopo di questo lavoro è dimostrare un teorema inedito nella
letteratura, che fornisce una caratterizzazione delle superfici sferiche
nello spazio iperbolico complesso in analogia all'equazione per la sfera unitaria immersa in di centro e direzione normale