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Advanced Spectral and Spatial Techniques for Hyperspectral Image Analysis and Classification
No full textRecent advances in sensor technology have led to an increased availability of hyperspectral remote sensing images with high spectral and spatial resolutions.
These images are composed by hundreds of contiguous spectral channels, covering a wide spectral range of frequencies, in which each pixel contains a highly detailed representation of the reflectance of the materials present on the ground, and a better characterization in terms of geometrical detail. The burst of informative content conveyed in the hyperspectral images permits an improved characterization of different land coverages. In spite of that, it increases significantly the complexity of the analysis, introducing a series of challenges that need to be addressed, such as the computational complexity and resources required.
This dissertation aims at defining novel strategies for the analysis and classification of hyperspectral remote sensing images, placing the focal point on the investigation and optimisation techniques for the extraction and integration of spectral and spatial information. In the first part of the thesis, a thorough study on the analysis of the spectral information contained in the hyperspectral images is presented. Though, independent component analysis (ICA) has been widely used to address several tasks in the remote sensing field, such as feature reduction, spectral unmixing and classification, its employment in extracting class-discriminant information remains a research topic open to further investigation. To this extend, a profound study on the performances of different ICA algorithms is performed, highlighting their strengths and weaknesses in the hyperspectral image classification task. Based on this study, a novel approach for feature reduction is proposed, where the use of ICA is optimised for the extraction of class-specific information. In the second part of the thesis, the spatial information is exploited by employing operators from the mathematical morphology framework.
Morphological operators, such as attribute profiles and their multi-channel and multi-attribute extensions, are proved to be effective in the modelling of the spatial information, dealing, however, with issues such as the high feature dimensionality, the high intrinsic information redundancy and the a-priori need for parameter tuning in filtering, which are still open. Addressing the first two issues, the reduced attribute profiles are introduced, in this thesis, as an optimised version of the morphological attribute profiles, with the property to compress all the meaningful geometrical information into a few features.
Regarding the filter parameter tuning issue, an innovative strategy for automatic threshold selection is proposed.
Inspired by the concept of granulometry, the proposed approach defines a novel granulometric characteristic function, which provides information on the image decomposition according to a given measure. The approach exploits the tree representation of an image, allowing us to avoid additional filtering steps prior to the threshold selection, making the process computationally effective.
The outcome of this dissertation advances the state-of-the-art by proposing novel methodologies for accurate hyperspectral image classification, where the results obtained by extensive experimentation on various real hyperspectral data sets confirmed their effectiveness.
Concluding the thesis, insightful and concrete remarks to the aforementioned issues are discussed
Incivilimento e storia filosofica nel pensiero di Antonio Rosmini
No full textIl presente lavoro si propone di indagare il tema dell'incivilimento e più in generale della storia a partire dalla prospettiva filosofica di Antonio Rosmini. Il filosofo di Rovereto risponde alle moderne teorie dello stato di natura, del perfettismo, del socialismo contrapponendo una antropologia che è propriamente antropologia filosofica. Con i grandi Agostino, Tommaso, Bonaventura ripropone nella modernità il tema fondamentale del peccato originale come nodo teologico e filosofico per comprendere l'uomo, il cittadino, il credente. La filosofia di Rosmini, basata sulla teoria del sintesismo delle tre forme dell'essere, mostra come il cristianesimo sia il vero incivilitore dei popoli. L'uomo è ontologicamente fondato in Cristo, l'umanità è per essenza cristiana. In questo modo, poiché la storia è da leggersi come storia sacra, storia della Chiesa-Società teocratica, anche la riflessione sul suo andamento non è più pensabile nel termine politico-sociale di "incivilimento", ma più propriamente in quello teologico di "cristificazione"
A robotic walking assistant for localisation and guidance of older adults in large public spaces
No full textAgeing is often associated with reduced mobility which is the consequence of a combination of physical, sensory and cognitive degrading. Reduced mobility may weaken older adults’confidence in getting out alone and traveling autonomously in large spaces. We have developed a robotic walking assistant, that compensates for sensory and cognitive impairments and supports the user’s navigation across complex spaces. The device is a walker with
cognitive abilities that we named c-Walker, and it is built around a common walker for elderly people. We show the difficulties that arise when building a robotic platform, focusing on hardware and software architecture for the basic functionalities and integration of high level software components. We developed an Extended Kalman Filter in such a
way that we are able to select a configuration of sensors that meets our requirements of cost, accuracy, and robustness. We describe the technological and scientific foundations for different guidance systems, and their implementation in the device. Some of them are “active” meaning that the system is allowed to “force a turn” in a specified direction. The other ones are “passive” meaning that they merely produce directions that the user
is supposed to follow on her own will. We show a comparison of the different guidance systems together with the results of experiments with a group of volunteers
Dynamic Camera Positioning and Reconfiguration for Multi-Camera Networks
No full textThe large availability of different types of cameras and lenses, together with the reduction in price of video sensors, has contributed to a widespread use of video surveillance systems, which have become a widely adopted tool to enforce security and safety, in detecting and preventing crimes and dangerous events. The possibility for personalization of such systems is generally very high, letting the user customize the sensing infrastructure, and deploying ad-hoc solutions based on the current needs, by choosing the type and number of sensors, as well as by adjusting the different camera parameters, as field-of-view, resolution and in case of active PTZ cameras pan,tilt and zoom. Further there is also a possibility of event driven automatic realignment of camera network to better observe the occurring event. Given the above mentioned possibilities, there are two objectives of this doctoral study. First objective consists of proposal of a state of the art camera placement and static reconfiguration algorithm and secondly we present a distributive, co-operative and dynamic camera reconfiguration algorithm for a network of cameras. Camera placement and user driven reconfiguration algorithm is based realistic virtual modelling of a given environment using particle swarm optimization. A real time camera reconfiguration algorithm which relies on motion entropy metric extracted from the H.264 compressed stream acquired by the camera is also presented
Forebrain GABAergic interneuron connectivity and BDNF signaling deficits in Engrailed-2 knockout (En2-/-) mice, a mouse model for autism spectrum disorder
No full textAutism spectrum disorders (ASD) comprise a genetically heterogeneous group of neurodevelopmental disabilities characterized by repetitive behaviors as well as deficits in communication and social/emotional interactions and behaviors. Defects in GABA transmission have been hypothesized to underlie the symptoms of ASD (Ben-Ari, Khalilov, Kahle, & Cherubini, 2012). Engrailed-2 (En2) is a homeodomain transcription factor involved in regionalization and patterning of the midbrain and hindbrain regions (Joyner, 1996; Gherbassi and Simon, 2006). En2 is expressed in the developing and adult mouse midbrain/hindbrain region (Joyner, 1996), as well as the adult mouse forebrain (Tripathi et al., 2009). Genome wide association studies have shown that two intronic single-nucleotide polymorphisms in the human En2 gene are significantly associated with ASD (Benayed et al., 2009). En2-/- mice lack the homeodomain of En2 (En2hd/hd mice; Joyner et al., 1991, referred to as En2-/-) and display neuropathological and behavioral changes relevant to ASD. We first investigated the distribution of different interneuron subtypes in the cerebral cortex and hippocampus of En2-/- mice. Results showed a significant loss of parvalbumin, somatostatin and neuropetide Y positive interneurons, in both regions of En2-/- brains.
Brain-derived neurotrophic factor (BDNF) is a crucial factor for the postnatal development of forebrain GABAergic neurons, namely PV interneurons. We therefore investigated whether altered BDNF expression may be related to the altered development of GABAergic interneurons, described in En2-/- mice. Considering the important role of BDNF in forebrain GABAergic interneuron development, we decided to determine whether interneuron loss in En2-/- forebrain might be related to altered expression of BDNF and its signaling receptors. We evaluated the expression of different BDNF mRNA and protein isoforms in various brain areas from wild-type (WT) and En2-/- mice. Quantitative RT-PCR indicated an alteration of various splicing variants of BDNF mRNA in the cerebral cortex but not hippocampus and cerebellum of adult En2-/- mice, as compared to WT controls. Immunoblot analyses instead revealed increased levels of mature BDNF and reduced levels of truncated- and pro-BDNF isoforms in the hippocampus of En2-/- vs. WT mice. These data indicate a role of BDNF in the anatomical phenotype of En2-/- mice, suggesting that BDNF might be involved in the developmental defects of the GABAergic system in this mouse model of ASD. We next investigated the effect of BDNF on GABAergic and glutamatergic neuron connectivity using primary cultures of hippocampal neurons from WT and En2-/- mice. Results showed that BDNF is able to increase the number of GABAergic and glutamatergic synaptic contacts in En2-/- hippocampal neurons. Taken together, our results suggest a beneficial role of BDNF in rescuing synaptic defects in En2-/- mice
Multimedia Content Analysis for Event Detection
No full textThe wide diffusion of multimedia contents of different type and format led to the need of effective methods to efficiently handle such huge amount of information, opening interesting research challenges in the media community.
In particular, the definition of suitable content understanding methodologies is attracting the effort of a large number of researchers worldwide, who proposed various tools for automatic content organization, retrieval, search, annotation and summarization. In this thesis, we will focus on an important concept, that is the inherent link between ''media" and the ''events" that such media are depicting. We will present two different methodologies related to such problem, and in particular to the automatic discovery of event-semantics from media contents. The two methodologies address this general problem at two different levels of abstraction. In the first approach we will be concerned with the detection of activities and behaviors of people from a video sequence (i.e., what a person is doing and how), while in the second we will face the more general problem of understanding a class of events from a set visual media (i.e., the situation and context). Both problems will be addressed trying to avoid making strong a-priori assumptions, i.e., considering the largely unstructured and variable nature of events.As to the first methodology, we will discuss about events related to the behavior of a person living in a home environment. The automatic understanding of human activity is still an open problems in the scientific community, although several solutions have been proposed so far, and may provide important breakthroughs in many application domains such as context-aware computing, area monitoring and surveillance, assistive technologies for the elderly or disabled, and more. An innovative approach is presented in this thesis, providing (i) a compact representation of human activities, and (ii) an effective tool to reliably measure the similarity between activity instances. In particular, the activity pattern is modeled with a signature obtained through a symbolic abstraction of its spatio-temporal trace, allowing the application of high-level reasoning through context-free grammars for activity classification. As far as the second methodology is concerned, we will address the problem of identifying an event from single image. If event discovery from media is already a complex problem, detection from a single still picture is still considered out-of-reach for current methodologies, as demonstrated by recent results of international benchmarks in the field. In this work we will focus on a solution that may open new perspectives in this area, by providing better knowledge on the link between visual perception and event semantics. In fact, what we propose is a framework that identifies image details that allow human beings identifying an event from single image that depicts it. These details are called ''event saliency", and are detected by exploiting the power of human computation through a gamification procedure. The resulting event saliency is a map of event-related image areas containing sufficient evidence of the underlying event, which could be used to learn the visual essence of the event itself, to enable improved automatic discovery techniques.
Both methodologies will be demonstrated through extensive tests using publicly available datasets, as well as additional data created ad-hoc for the specific problems under analysis
Advanced Query Paradigms for the Novice User
No full textQuery answering is one of the most important processes in search systems, for it connects users to the information stored in data sources. A query is a set of specifications or constraints that the user provides to describe the objects of interest. As such, answering a query means retrieving those objects from the data source that match the user constraints. An answer from a search system may not fully satisfy the user. This happens if the answer does not contain the required object or it contains a number of irrelevant results. Commonly, the user does not know how to describe the query and ends up with one overly generic or specific or, even worse, she is not even aware of the correct conditions to describe the expected results.
These problems are particularly evident when the database is interrogated by a novice user who, by definition, does not have sufficient technological skills to understand complicated query languages, or simply gives up if the system does not respond properly or timely. In this dissertation, we focus on three common problems in the broad query answering process to help novice users find the correct answers when the system does not provide sufficient support. First, we look at the empty answer problem, where the user provides a very specific query for which no answer exists in the database. In particular, we concentrate on interactive approaches for novice users. We end up with a rich probabilistic framework that includes user preferences and smoothly guides the user towards the most likely answers by means of simple yes/no questions on the query conditions to be discarded. Second, we analyze the information overload problem, that is complementary to the first. In this case the user provides a too generic query that returns a large set of potentially irrelevant results. We tackle the problem in structured databases, and more specifically, labeled graphs. The solution we propose returns a set of refinements (i.e., more specific queries) of the input query that, once executed, covers all the initial results. Third, we propose and study a completely novel query paradigm that assumes that the user is not able to describe the query conditions to retrieve the objects of interest. In this regard, we introduce exemplar queries, that allow the user to specify a single element in the result set and let the system infer the others. We provide clear semantics and a solution that works in large knowledge graphs. Finally, we validate the solutions for the three problems both in terms of theoretical results and experimental evaluation and we prove that the proposed methods efficiently scale up to very large real datasets
Criminalità, giustizia e ordine pubblico a Torino nella prima metà dell'Ottocento (1814-61)
Get PDFIl lavoro si concentra sul tema della criminalità e del
controllo sociale nella città di Torino di primo Ottocento. Essa inquadra un periodo cruciale e fino ad ora poco studiato della storia torinese, che parte con la transizione dal dominio napoleonico al reinsediamento sabaudo e si conclude negli anni precedenti la svolta unitaria.
Grazie a un ampio scavo archivistico condotto su fondi italiani e francesi, la tesi affronta le trasformazioni della politica giudiziaria del Regno di Sardegna mettendo a fuoco, in una prima parte, continuità e discontinuità rispetto alle innovazioni istituzionali portate dai
francesi nel settore della polizia: la rifondazione dell’ufficio del Vicariato urbano e la travagliata formazione di un corpo di polizia ‘moderno’ ispirato alla Gendarmerie francese (i Carabinieri Reali) fanno da sfondo ai primi anni della Restaurazione sabauda, nei quali si
collocano anche i tentativi, poi abortiti, di svecchiamento della legislazione in materia giudiziaria. In una seconda parte sono esaminate le reggenze di Carlo Felice (1821-1831) e di Carlo Alberto (1831-1849), contraddistinte da una profonda riorganizzazione del settore della giustizia che incide sia sulla struttura normativa (l’emanazione di nuovi codici penali e di procedura) sia sulle modalità concrete della prassi giudiziaria. La crescita della popolazione
innescata dalle trasformazioni economiche oltre che dall’arrivo di numerosi emigrati italiani ed esteri, spinge le magistrature sabaude a elaborare nuovi strumenti repressivi di fronte al pericolo delle «nuove classi pericolose». A questo tema, comune per altro a tutti gli stati ottocenteschi europei, è dedicata l’ultima parte del lavoro, che ricostruisce la politica giudiziaria sabauda post 1848 alla luce delle crescenti tensioni emerse fra i poteri istituzionali del regno. Una parte consistente del lavoro è poi esclusivamente dedicata all'analisi della criminalità torinese e delle sue evoluzioni nel periodo preso in esame che videro il capoluogo piemontese trasformarsi da una modesta capitale di un regno di seconda grandezza a centro politico della nuova compagine statale unitaria
Le origini, le linee e le prospettive di una cristologia filosofica del Novecento. La "cristità" del pensare in Teodorico Moretti-Costanzi.
No full textIl lavoro si è dedicato all'esposizione del pensiero di Teodorico Moretti-Costanzi dalla sua formazione fino alla maturità attraverso la nuova originale prospettiva di comprensione teoretica data dal concetto di cristità. L'attenzione a tale concetto deriva dalla connotazione che assume la cristità nel pensiero di Moretti-Costanzi: tutta l'opera del filosofo è compresa come un tentativo di sviluppare un cristologia fondativa dell'esistenza e del senso dell'esistenza, tale cristologia si diversifica dalla canonica comprensione, nei contenuti, del concetto tradizionale di cristologia stessa e per tale motivo prende appunto il nome di cristità. Il lavoro si è concentrato pertanto nell'approfondimento di tutte le maggiori opere di Moretti-Costanzi dalla giovinezza fino alla maturità analizzate attraverso la linea interpretativa trovata nel concetto di cristità. Infine è statto sviluppato una confronto fra due cristologie novecentesche: quella di Moretti-Costanzi, appunto, e quella di Romano Guardini. Il confronto si è concentrato sull'ispirazione delle due riflessioni cristologiche che di fatto è la medesima, ovvero il pensiero di San Bonaventura; si è cercato così di mettere in evidenza le continuità e le differenze tra le conclusioni dei due filosofi rispetto alla considerazione dell'orizzonte bonaventuriano. Tale percorso di ricerca svolto sui testi è stato completato da un'attività di ricerca svolta direttamente nell'archivio Moretti-Costanzi. Grazie alla concessione della Fondazione “Siro Moretti-Costanzi” è stato possibile ottenere la concessione di trascrivere, in appendice alla tesi di dottorato, un'opera inedita di Teodorico Moretti-Costanzi, per la precisione l'ultima opera dell'autore, composta un anno prima della morte: Naturalità-Trascendenza-Sapienza. Tale scritto è risultato oltremodo necessario ai fini del lavoro di ricerca in quanto ripercorre tutto l'orizzonte del pensiero morettiano alla luce di quel concetto di cristità che è stato preso come originale metro di interpretazione dell'opera di Moretti-Costanzi
Padri flessibili e madri precarie. Modelli culturali, pratiche quotidiane e processi biografici innovativi in corso di negoziazione.
No full textLa tesi ha l'obiettivo di comprendere quale sistema di nuovi valori, aspirazioni e norme sociali, rispetto all'ideologia delle sfere separate, orienta l'agire di neogenitori in coppie dual precarious e con quali conseguenze dal punto di vista soggettivo, tanto nella quotidianità quanto lungo il corso biografico. Il lavoro di ricerca adotta un approccio sociologico di tipo interpretativo e si articola su tre fuochi di analisi specifici: gli assetti culturali e normativi influenti nei processi di sense-making tra famiglia e lavoro, le pratiche quotidiane di boundary-work fra gli ambiti di vita e i processi decisionali lungo le esperienze biografiche. La tesi fa luce su come i meccanismi, allo stesso tempo pratici e culturali, collocati in contesti familiari, strutturali e culturali specifici, concorrano, talvolta in modo conflittuale e talvolta attraverso taciti processi di adattamento, ad innovare e, per altri versi, a riprodurre i modelli egemoni di conciliazione famiglia-lavoro