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Educazione linguistica: l'editoria per ragazzi tra norma e innovazione
No full textIl presente studio indaga il ruolo svolto dalla letteratura per l infanzia e per ragazzi nella didattica, nell acquisizione e nell apprendimento dell italiano come prima lingua, in particolare in ambito extrascolastico.
I libri per bambini e per ragazzi, (insieme ai libri di scuola, ai programmi televisivi, ai cartoni animati, alle canzoncine e filastrocche, alle ninna nanne) si configurano infatti come fonti importanti di input linguistico per i bambini in età prescolare e scolare. Essi rappresentano un punto di osservazione fondamentale non solo per conoscere i processi sociologici attraverso i quali la società italiana ha veicolato (e continua a veicolare) i propri modelli culturali, ma anche per individuare la norma linguistica di riferimento e gli schemi di didattica della lingua materna, nel nostro caso l italiano.
Indagando la naturale inclinazione pedagogica, e in molti casi la programmaticità esplicita, del segmento editoriale dedicato all infanzia, il lavoro mostra la doppia identità connaturata alle opere destinate ai bambini: narrare e formare. In quest ottica, ma con un occhio attento in particolare all asse educativo destinato alla componente linguistica, abbiamo osservato in diacronia e in sincronia la produzione editoriale per bambini e ragazzi per scoprire la coscienza del delicato compito glottodidattico rivestito dalle queste opere.
Partendo dagli importanti dati forniti da Lessico elementare di Marconi/Ott/Pesenti/Rati/Tavella (1994), lo studio si è focalizzato sui repertori di fiabe presenti nelle proposte editoriali, non solo a stampa, ma anche tra cinema e tv. Concentrandosi in particolare sulle fiabe di Perrault, dalla traduzione di Carlo Collodi alle edizioni Disney, è stato infine elaborato un itinerario glottodidattico incentrato sulla fiaba, sulla lingua della fiaba e in particolare sull uso dei pronomi personali. L itinerario, che si fonda su un metodo induttivo/deduttivo (Esperimenti grammaticali di Lo Duca, 2005) può essere modulato per diverse fasce d età con finalità e obiettivi diversi a seconda del destinatario specifico dell intervento didattico
Hybrid modile femtocells: the mmWave solution for 5G Moving Networks
No full textMobile connectivity is a vital requirement for peoples everyday life.
Users would like to have unlimited access to information for anyone, anywhere, and anytime, especially in public means of transport where they spend a lot of time travelling. The connectivity to Internet becomes difficult for passengers because public transportation vehicles suffer from the low quality signal from the outside wireless network.
One of the requirements of the 5G Network is to guarantee a high level of service to users wherever they are, both at home, office, or in public means of transport. Users on the move shall have the impression that the network infrastructure follows them", in situations where they suffer from poor coverage today.
A first solution to improve the broadband connectivity is to deploy more eNodeBs close to buses or train routes, but it requires high investment for providers and a higher complexity in managing the increasing number of handover. The rapid growth in the deployment of LTE femtocells for indoor use and their benefits have led many authors to propose using them even in vehicles, implementing the so-called Moving Networks. This work shows that the use of pure LTE mobile femtocells exhibits relevant issues in terms of interference and consequently poor performance in a realistic use. In order to overcome these issues, we propose to adopt the millimeter Wave (mmWave) technology in the Moving Networks, creating the Hybrid Mobile Femtocells.
The new technology will satisfy the 5G requirements of enhancing the capacity and coverage for the users on the move and to enable long battery life, due to the short range transmission between the user equipments and the access point.
In the thesis we discuss the concerns arising from applying mmWave communications at 60 GHz inside vehicles. We provide a new throughput analysis in order to benchmark our proposal to the solutions presented in literature. Furthermore, we analyse the system
performance in two different scenarios: a sub-urban setup and in an urban configuration where different kind of cells are deployed. The results obtained by Matlab simulations, show a noticeable improvement of the global system throughput by using Hybrid Mobile Femtocells
Design and synthesis of new processable materials for application in organic devices.
No full textNew materials were designed and synthetized for photovoltaic applications featuring ability to be processed from green solvents including alcohol or water.
In the synthesis of semiconductor materials, the well-known diketopyrrolopyrrole (DPP) unit was used as main building block for its features as excellent electron-acceptor unit in compounds with low bandgap.
Six small molecules, based on DPP unit endcapped with triazolo group were synthetized and functionalized with solubilizing peripheral chains that allowed the dispersion in nonorganic and toxic solvents. All molecules were characterized through NMR and IR spectroscopy; in addition, physicochemical properties of the derivatives including solubility in variety of solvents, solution and film absorption and emission, and cyclic voltammetry (CV) were studied. Bulk heterojunction solar devices, using the synthetized materials as donors and PC60BM as acceptors were fabricated and tested.
Furthermore, some polymers were designed to comprise DPP unit with polar triethylen glycol (Teg) side chains and different comonomers including vinyl, ethylhexyloxy benzodithiophene or functionalized thiophene ring. The majority of materials were synthesized using the Stille condensation reaction, but also an environmentally friendly process, the Direct Heteroarylation Polymerization (DAHP) reaction was profitably used.
All materials were extensively characterized exhibiting low values of bandgaps and tested as donors in blends with PC70BM for photovoltaic response in both conventional and inverted device architectures, demonstrating, for the best polymer, a power conversion efficiency (PCE) around 1.5%. Interestingly, in field effect transistors, the same material, shows hole mobility approaching 0.015 cm2/Vs
Real-Time Networks for Robotics and Industrial applications: Research Challenges and Novel Solutions
No full textThe increasing adoption of smart sensors and actuators enables industrial applications to process data in a decentralized way. In this context, communication networks play a key role, as industrial automation applications require network architectures and communication protocols, wireless and wired, able to support the interaction between multiple devices not only in a reliable way, but also guaranteeing the meeting of real-time constrains of the supported applications. The distributed processing among coordinated automation devices includes the cooperation of robot teams. However, cooperative robot networks impose additional communication constraints to those required in the automation context.
This thesis originates from the collaboration with STMicroelectronics and targets mechanisms, algorithms and protocols that meet the communication requirements of cooperative robot applications in the industrial automation scenario. With the aim to avoid the definition of "yet another protocol", the work mainly focuses on the existing communication technologies adopted in the industrial context. In particular, innovative mechanisms, algorithm and protocols built upon standard communication technologies are investigated, with
the aim to meet both the specific requirements imposed by cooperative robot applications (e.g., mobility and low latency) and those that are typical of industrial automation networks.
In the thesis, innovative solutions for several communication technologies, both wired and wireless, are presented and described. Among the network technologies addressed, EtherCAT, Bluetooth Low Energy, Sub-GHz Communications, the IEEE 802.15.4e and IEEE 802.11 standards. Evaluations through simulations, analysis and experiments on proof-of-concept implementations are reported, which prove the effectiveness and the suitability of the proposed solutions
New products from Cynara cardunculus L.
No full textThe goal of the researches that make up the present study was to explore the potential of C. cardunculus L. to be exploited for some new uses.
Although the globe artichoke has deep roots in the culinary traditions of the Mediterranean countries, it requires nowadays innovations that remove the difficulties of its preparation and make it easier and faster to consume. The artichoke as a minimally processed and ready to use product addresses this need. The results presented in this thesis show that by choosing the right cultivar-packaging combination, it is possible to extend the shelf life of the product to at least 7 days from packaging.
The cultivated and wild cardoon produce large amounts of biomass, even under low-input conditions, thanks to their hardiness and the perfect match with Mediterranean climate. The data provided in this thesis confirm the cardoon as a possible source of renewable energy, both for its biomass yield and for biomethane yield of its silage. The volume of biomethane produced from the ensiled cardoon (between 200 and 250 Nm3 per t DM) is comparable to that produced by the ryegrass silage, triticale and wheat. Silage of cultivated cardoon genotypes achieved volumes of biomethane (from 3,700 to 4,530 Nm3 ha-1) that are comparable to those obtained with maize grown under an intermediate input intensity regime.
Much of the biomass produced by globe artichoke plants remains in the field as crop residues, this biomass can be exploited for the production of bioethanol, considering its richness in complex carbohydrates (cellulose and hemicellulose) and even in simple sugars (glucose and fructose ). The enzymatic saccharification of non-pretreated biomass of residues of two globe artichoke cvs. ('Opera F1' and Spinoso sardo') has given rise to a potential yield of 85-109 kg of EtOH per t DM and 1,440-1,520 kg of EtOH per ha
Monitoraggio, stima e previsione real-time del traffico veicolare con tecnologie ITS. Implementazione di un sistema sperimentato nell'area urbana di Catania
No full textFirst of all, the main focus of this study is the design and development (installation, implementation and calibration) of a traffic monitoring, estimating and short-term forecasting system, through the integration of real-time traffic data in a dynamic simulation model. The proposed methodology allows the identification of the conceptual model that represents the basis of the system's architecture, in order to define a set of required services, functional relationships and specific characteristics identified from the stakeholders needs, which will be involved by this system.
The described methodology is applied to the urban area of Catania (Italy) through the implementation of a traffic monitoring, estimation and forecasting system, equipped with radar sensor and a central control station for traffic data elaborations.
By using obtained data from the implemented simulation model, two further methodologies are presented in this thesis. The first methodology is based on the development of a detailed statistical analysis procedure for reliability assessment of data coming from traffic monitoring systems and simulation models. The second methodology develops a statistical approach for capturing the variability of travel time reliability (TTR) in an extended traffic network, incorporating travel time analysis in order to evaluate their variation and to define the workability of the transport network.
To conclude, the final aim of this work is to increase the knowledge of the actual dynamic of road traffic in urban areas, to monitor the reliability of the transport system and to obtain useful data and information that can contribute to the implementation of an optimal control of mobility system, through a more efficient and integrated use of the road infrastructure and the available devices on it
Context Awareness in First Person Vision
No full textThe First Person Vision (FPV) paradigm allows to seamlessly acquire images of the world from the user's perspective. Compared to standard Third Person Vision, FPV is advantageous for building intelligent wearable systems able to assist the user and augment his abilities. Given their intrinsic mobility and the ability to acquire user-related information, FPV systems have to deal with a continuously evolving environment. Moving from the observation that data acquired from a first person perspective is highly personal, we investigate contextual awareness for First Person Vision systems. We first focus on the task of recognizing personal locations of interest from egocentric videos. We consider personal locations at the instance level and address the problem of rejecting locations not of interest for the user. To challenge the problem, we introduce three datasets of 10 personal locations which we make publicly available, and perform a benchmark of different wearable devices and state-of-the-art representations. Moreover, we propose and evaluate methods to reject negative locations and perform personal location-based temporal segmentation of egocentric videos. As a second aspect, we investigate the anticipation of object interaction. We propose and define the task of next-active-object prediction as recognizing which objects are going to be interacted with, before the actual interaction begins. Even if recognizing next-active-objects is in general not trivial in unconstrained settings, we show that the First Person Vision paradigm provides useful cues to address the challenge. We propose a next-active-object prediction method based on the analysis of egocentric object trajectories and assess its superior performances with respect to other cues such as object appearance, distance from the center of the frame, presence of hands and visual saliency. In appendix, we also report some investigations on extraction features directly from wide angle images
Architettura storica e terremoto. Il percorso della conoscenza dell edificio per la valutazione della sicurezza e per il progetto di restauro conservativo
No full textLa ricerca si inquadra nel filone di studi inerenti la prevenzione del rischio sismico degli edifici murari storici e, in particolare, indaga il ruolo della conoscenza del fabbricato nel progetto di restauro con miglioramento sismico.
La normativa vigente (Norme Tecniche per le Costruzioni 2008 e Linee guida per la valutazione e riduzione del rischio sismico del patrimonio culturale) sancisce l importanza preminente della fase conoscitiva e in particolare le Linee Guida sistematizzano le attività di indagine in una metodologia strutturata, detta percorso di conoscenza.
Per la norma la conoscenza si può acquisire a vari livelli di approfondimento, detti livelli di conoscenza (LC), cui sono legati coefficienti di sicurezza, detti fattori di confidenza (FC), che rendono cautelativa la verifica (nello stato di fatto e nello stato di progetto) penalizzando i livelli di conoscenza più bassi. Per la definizione di LC e FC le Linee Guida propongono una procedura diversa rispetto a quella contenuta nelle NTC08 in cui il livello di conoscenza non è necessariamente legato alla esecuzione di indagini di caratterizzazione meccanica dei materiali.
A partire dall analisi dell approccio normativo, la ricerca intende dimostrare le seguenti tesi: (i) il Fattore di Confidenza così come definito nelle Linee Guida non riesce a cogliere le differenze anche sostanziali che possono sussistere da percorsi di conoscenza diversi per tipologia di indagine e qualità delle informazioni raccolte (ii) che non sempre alla esecuzione di un numero maggiore di indagini corrisponde una conoscenza più approfondita, bensì l approfondimento della fase di conoscenza è legato piuttosto alla tipologia di indagini svolte e alla qualità dei risultati ottenuti.
L obiettivo del lavoro è di chiarire quali sono le tipologie di indagini più utili per conseguire un livello di conoscenza adeguato sia per una valutazione della sicurezza attendibile sia per la definizione dei criteri di intervento volti alla sicurezza e alla conservazione dell edificio.
La metodologia di lavoro ha previsto la preliminare analisi delle indicazioni della normativa per l espletamento della fase conoscitiva, con particolare riguardo al percorso della conoscenza delineato dalle Linee Guida. Una analisi comparativa di diversi percorsi di conoscenza è stata svolta su un campione di 34 esempi di verifiche sismiche eseguite su edifici storici reali secondo l approccio delle Linee Guida con il duplice obiettivo di verificare la congruenza tra esiti conoscitivi e fattore di confidenza, e individuare una gerarchia di indagini che contraddistinguono un percorso di conoscenza ottimale. Quest ultimo è infine illustrato attraverso la sua applicazione a un caso studio.
Una nota conclusiva mette in evidenza come una conoscenza adeguata dell edificio è legata non alla quantità delle indagini svolte, bensì alla tipologia delle indagini e alla qualità delle informazioni raccolte. In particolare lo studio evidenzia come un livello di conoscenza ottimale sia raggiungibile attraverso l'indagine storica e il rilievo diretto
Dynamic identification of the Augusta hybrid base isolated building using data from full scale push and sudden release tests
No full textA three-story reinforced concrete building in Augusta (IT), isolated at the base and designed according to the provisions
of the latest Italian seismic regulations,
was subjected to a series of push and sudden release tests in March 2013.
The Augusta isolation system is hybrid, consisting of 16 High Damping Rubber Bearings (HDRB) and 20 Low Friction Sliding Bearings (LFSB). The tests were characterized by a long quasi-static phase, where the building was pushed slowly to the desired
displacement amplitude (sliding velocity , strain bearing demand ),
and a dynamic phase where the building was left free to oscillate.
The duration of the dynamic phase was utmost the duration of the static phase.
The recordings included the displacements at the isolation level and the floor accelerations.
A baseline fitting scheme was developed for the removal of the low frequency noise in the records.
Application of the adjustment scheme provided reliable estimates of the floor velocities and displacements.
The advantage of the proposed signal processing method other than its simplicity,
is its ability to account for boundary conditions, for instance initial and residual displacements.
Once the signals obtained from all eight tests performed were adjusted,
they were used in the identification of the non-linear isolation system and the
flexible superstructure (linear in the range of interest).
The identification was performed in the time domain using the Covariance Matrix Adaptation Evolution Strategy,
a stochastic algorithm for difficult, non linear black-box optimization.
The identification of the isolation system provided the mass of the rigid block,
the bi-linear properties used in the mechanical representation of the rubber bearings
and the sliding coefficient of friction for the Coulomb model used in the modelling of the sliders.
The obtained parameters, showed that rubber bearing properties were closer to the corresponding
static laboratory properties, therefore implying that after the long quasi-static phase
the HDRBs did not have time to recover their dynamic properties.
The identified sliding coefficient of friction was in average , leading to significant energy dissipation.
The identified superstructure properties were the distribution of the floor masses,
the modal frequencies, damping ratios and mode shapes.
The identified data for the isolation system and the superstructure were input
in a synthesized model of the isolated Augusta building,
for the dynamic response simulation of the structure.
A constrained optimization algorithm was developed ad hoc
for the time-step solution of the coupled equations of motion.
The obtained simulated response of the Augusta building
matched the experimental response, in terms of displacements, velocities and accelerations
Robotics and intellectual disabilities: models and treatment
No full textPublic perception of an emerging scientific and technological product is important for the acceptance of such a product. Ethical studies based on public surveys toward using robots in eldercare and other applications, showed a high acceptance for pet-like therapeutic robot, the human-like care robot, and a surveillance care robot. However, it also reported a rejection in the case of a bathing robot because of the judgment that the robot-based action would be inferior to the human-based action and that it would take away jobs from human workers. Taking into account this scenario, chapter IV (4.1) focus on the acceptance by practitioners that work on a daily basis with children with intellectual disabilities, and on a group of university students from two classes concerned with social professions: education and psychology.
Moreover, the purpose of the other study in the chapter IV (4.2) is to examine the acceptance and willingness to use robots among psychology students with Italian (ITA) and British (UK) background cultures in order to evaluate cultural differences in the acceptance of robotics by future psychology practitioners.
Both studies were conducted using a platform for Socially Assistive Robotics and a questionnaire based on the Unified Theory of Acceptance and Use of Technology (UTAUT) model. In this case, the aim was to identify the capability of items in UTAUT questionnaire to reveal cultural differences, and, thus, the main factors that may influence each group in the use of robots in their future practice. This negative attitude is one of the biggest challenges that scientific research must address to be completely successful in giving actual benefits in the field of education and care.
This rapid progress in technology, especially in the area of robotics, offers numerous possibilities for innovation in the education and care of individuals. Starting from these findings, in the chapter V my on-going research aims to identify effective modalities for treatment of Autism Spectrum Disorder (ASD) through interaction with a robot, and to integrate them into existing therapeutic protocols to improve their efficacy. I detail the methodology and give the results of a pilot clinical trial, focused on imitation skills, with three children affected by ASD and Intellectual Disability under treatment in a research centre specialized in the care of children with disabilities. Analysis of these initial results encourages the development of effective protocols in which the robot becomes a mediator between the child with ASD and humans and suggests some research avenues for focus in the future.
However, the robotics is not only social. For this reason the aim of chapter VI, is artificial life where the models derived from the data , implement artificial organisms that replicate experimental observations. Specific skills or behaviours are not directly imitated or reproduced, as schematic photographs of a part of reality, but emerge as a result of adaptation processes put in place by the new reality built artificially.
Traditionally, artificial life realizes models that simulate psychophysical activities. In fact, in the chapter VI, I will present the experimental results of a cognitive robotic approach for modelling the human cognitive deficit known as Unilateral Spatial Neglect (USN), where I replicated a previous experiment with human patients affected by the USN and iCub robotic platform. The numerical results show that the robot simulate the behaviours previously exhibited by humans and this last work of dissertation highlights some possible advantages of the use of robotic platforms to model and study cognitive dysfunctions of the human brain