Dissertations / Theses: 'Pen drive'

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Signorelli, Mirko. "Inferring Community-driven Structure in Complex Networks." Doctoral thesis, Università degli studi di Padova, 2017. http://hdl.handle.net/11577/3422400.

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Despite a long tradition in the study of graphs and relational data, for decades the analysis of complex networks was limited by difficulties in data collection and computational burdens. The advent of new technologies in life sciences, as well as in our daily life, has suddenly shed light on the many interconnections that our world features, from friendships and collaborations between individuals or organizations, to functional couplings between cellular molecules. This has highly facilitated the collection of relational data, fostering an unprecedented interest in network science. Understanding relations encoded in complex networks, however, still represents a challenging task, and statistical methods that can help to summarize and simplify complex networks are needed. In this thesis we show that often one can gain a deep insight of a network by focusing their attention on communities, i.e. on clusters of nodes, and on the relations that exist between them. We begin by presenting NEAT, a network-based test that allows to assess relations between gene sets in a gene interaction network. NEAT extends traditional gene enrichment analysis tests by incorporating information on interactions between genes and it overcomes some limitations of existing network enrichment analysis approaches. Then, we propose two extended stochastic blockmodels that allow to infer the relations that exist between communities from relations between pairs of individuals in a social network. We advocate the use of penalized inference to estimate these models, with the aim of deriving a sparse reduced graph between communities. Application of these models to bill cosponsorship networks in the Italian Chamber of Deputies allows us to reconstruct the pattern of collaborations between Italian political parties from 2001 to 2015. Finally, we propose a novel clustering strategy for sequences of graphs, based on mixtures of generalized linear models. We show that the proposed clustering method not only is capable to retrieve subpopulations of networks within a cross-sectional or longitudinal sequence of networks, but it also allows to directly characterize them by considering each of the components that form the mixture model. Per decenni, lo studio di reti complesse è stato limitato da difficoltà nella raccolta dei dati e computazionali. L’avvento di nuove tecnologie, tanto nelle scienze biologiche quanto nella nostra vita quotidiana, ha enormemente facilitato la raccolta di dati relazionali, alimentando un interesse nello studio di reti complesse senza precedenti. La comprensione delle relazioni rappresentate in reti complesse, tuttavia, è ancora oggi una sfida impegnativa, che richiede lo sviluppo di metodi statistici innovativi, in grado di riassumere e semplificare le informazioni contenute in reti complesse. In questa tesi discutiamo la possibilità di interpretare una rete attraverso lo studio delle relazioni fra gruppi di nodi. La trattazione comincia da NEAT, un test per lo studio delle relazioni fra gruppi di geni in reti biologiche. NEAT estende i test di gene enrichment analysis sfruttando informazioni sulle relazioni fra geni rappresentate tramite una rete, risolvendo al contempo le limitazioni dei test per network enrichment analysis preesistenti. Inoltre, proponiamo due estensioni di modelli stocastici a blocchi per lo studio delle relazioni fra gruppi di individui in reti sociali e l’utilizzo di metodi di inferenza penalizzata per derivare un grafo ridotto che sintetizzi le relazioni fra blocchi di nodi. L’applicazione di tali modelli a reti di cosponsorizzazione delle proposte di legge nel Parlamento Italiano ci consente di ricostruire le collaborazioni fra i partiti politici italiani dal 2001 al 2015. Infine, proponiamo una nuova strategia di clustering per sequenze di grafi basata su misture di modelli lineari generalizzati. Tale metodologia consente non solo di individuare sottopopolazioni di grafi in popolazioni di reti, ma anche di caratterizzare ciascuna di esse per mezzo delle componenti che formano la mistura.

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Duncan, Kaylia Mekelda. "Dynamics of tumor progression and therapy response in Il-6 and Myc driven plasma cell malignancy." Thesis, University of Iowa, 2013. https://ir.uiowa.edu/etd/4619.

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Emerging evidence indicates that 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) and computed tomography (CT) are useful imaging modalities for evaluating tumor progression in transgenic mouse models of solid human cancers, but the potential of integrated FDG-PET/CT for assessing tumor development in genetically engineered mouse models of liquid human cancers - including neoplasms of immunoglobulin (Ig)-producing plasma cells - has not been established. Here we use a double-transgenic strain of laboratory mice, designated C.IL6Myc, that recapitulates key features of human plasma cell myeloma (a.k.a. multiple myeloma [MM]) to demonstrate that FDG-PET/CT affords a useful research tool for assessing plasma cell tumor (PCT) development in a serial, objective and, importantly, stage- and lesion-specific manner. Supported by serum biomarker analyses (Ig level, paraprotein) and histopathological findings in C.IL6Myc mice undergoing PCT development, the newly generated FDG-PET/CT data set demonstrates the potential of this imaging modality for preclinical basic and translational MM research. PET imaging of genetically engineered mice in which MM-like tumors arise predictably in an intact immunocompetent microenvironment may facilitate the design and testing of new approaches to the treatment and prevention of MM in humans.

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Jahagirdar, Anant. "SOLAR DRIVEN PHOTOELECTROCHEMICAL WATER SPLITTING FOR HYDROGEN GENERATION USING MULTIPLE BANDGAP TANDEM OF CIGS2 PV CELLS AND TH." Doctoral diss., University of Central Florida, 2005. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/3505.

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The main objective of this research was to develop efficient CuIn1-xGaxS2 (CIGS2)/CdS thin film solar cells for photoelectrochemical (PEC) water splitting to produce very pure hydrogen and oxygen. Efficiencies obtained using CIGS2 have been lower than those achieved using CuInSe2 and CuIn1-xGaxSe2. The basic limitation in the efficiencies is attributed to lower open circuit voltages with respect to the bandgap of the material. Presently, the main mechanism used to increase the open circuit voltage of these copper chalcopyrites (CuInSe2 and CuInS2) is the addition of gallium. However, addition of gallium has its own challenges. This research was intended to (i) elucidate the advantages and disadvantages of gallium addition, (ii) provide an alternative technique to the photovoltaic (PV) community to increase the open circuit voltage which is independent of gallium additions, (iii) develop highly efficient CIGS2/CdS thin film solar cells and (iv) provide an alternative material in the form of CIGS2/CdS thin film solar cells and an advanced technology in the form of a multiple bandgap tandem for PEC water splitting. High gallium content was achieved by the incorporation of a highly excess copper composition. Attempts to achieve high gallium content produced reasonable but not the best solar cell performance. Few solar cells developed on a molybdenum back contact and an ITO/MoS2 transparent conducting back contact showed a PV conversion efficiency of 7.93% and 5.97%, respectively. The solar cells developed on the ITO/MoS2 back contact form the first generation CIGS2/CdS thin film solar cells and 5.97% is the first ever reported efficiency on an ITO/MoS2 transparent back contact. Reasons for the moderate performance of these solar cells were attributed to significant porosity and remnants of unsulfurized CuGa alloy in the bulk of CIGS2. This was the first attempt to a detailed study of materials and device characteristics of CIGS2/CdS thin film solar cells prepared starting with a highly excess copper content CIGS2 layer. Next, excess copper composition of 1.4 (equivalent to gallium content, x = 0.3) was chosen with the aim to achieve the best efficiency. The open circuit voltage was enhanced by depositing an intermediate layer of intrinsic ZnO between CdS and ZnO:Al layers. The systematic study of requirements for such a layer and further optimization of its thickness to achieve a higher open circuit voltage (which is the greatest challenge of the scientific community) forms an important scientific contribution of this research. The PV parameters for CIGS2/CdS thin film solar cell as measured officially at the National Renewable Energy Laboratory were: open circuit voltage of 830.5 mV, short circuit current density of 21.88 mA/cm2, fill factor of 69.13% and photovoltaic conversion efficiency of 11.99% which sets a new world record for CIGS2 cells developed using sulfurization and the open circuit voltage of 830.5 mV has become the "Voc champion value". New PEC setups with the RuS2 and Ru0.99Fe0.01S2 photoanodes were developed. RuS2 and Ru0.99Fe0.01S2 photoanodes were more stable in the electrolyte and showed better I-V characteristics than the RuO2 anode earlier used. Using two CIGS2/CdS thin film solar cells, a PEC efficiency of 8.78% was achieved with a RuS2 anode and a platinum cathode. Results of this research constitute a significant advance towards achieving practical feasibility and industrially viability of the technology of PEC hydrogen generation by water splitting. Ph.D. Department of Mechanical, Materials and Aerospace Engineering; Engineering and Computer Science Materials Science and Engineering

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Chen, Kui. "Modeling and estimation of degradation for PEM fuel cells in real conditions of use for mobile applications." Thesis, Bourgogne Franche-Comté, 2020. http://www.theses.fr/2020UBFCA022.

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La PEMFC sont une source d'énergie propre en raison de ses avantages comme une efficacité énergétique élevée, un faible bruit, une température de fonctionnement faible et zéro polluant. Cependant, la courte durée de vie causée par la dégradation a un grand impact sur l'intégration de la PEMFC dans les systèmes de transport. Le pronostic et la gestion de la santé sont un moyen important pour améliorer les performances et la durée de vie de la PEMFC. Cette thèse présente cinq méthodes de pronostic de dégradation pour la PEMFC. Elle examine l'influence des principales conditions de fonctionnement, incluant le courant de charge, la température, la pression d'hydrogène et l'humidité relative, sur la dégradation de la PEMFC. La dégradation globale et les phénomènes réversibles sont analysés en se basant sur les données numériques issues de trois expériences de PEMFC menées dans des conditions différentes d'usage (une flotte de véhicules à PEMFC et deux bancs de test de type laboratoire). Un premier modèle basé sur l'algorithme de filtre de Kalman UKF (Unscented Kalman Filter) et le modèle de dégradation de la tension est proposé pour prédire la dégradation de la PEMFC dans les véhicules électriques à pile à combustible. Puis, la méthode hybride basée sur l'analyse des ondelettes, la machine d'apprentissage extrême et l'algorithme génétique est proposée pour construire un deuxième modèle de dégradation de la PEMFC. Pour prévoir la dégradation du PEMFC avec des données de expérimentales limitées, la méthode améliorée basée sur sur la combinaison du modèle des réseaux de neurones gris, l'optimisation de l'essaim de particules et les méthodes de fenêtre mobile, est utilisée pour développer le troisième modèle. La quatrième contribution est un modèle de pronostic de vieillissement de la PEMFC fonctionnant dans différentes conditions, en utilisant le réseau neuronal de rétro-propagation et l'algorithme évolutif. Enfin, un pronostic de dégradation de la PEMFC basé sur le réseau neuronal en ondelettes et l'algorithme de recherche du coucou est proposé pour prédire la durée de vie restante de la PEMFC Proton Exchange Membrane Fuel Cells (PEMFC) is a clean energy source because of the merits like high energy efficiency, low noise, low operating temperature, and zero pollutants. However, the short lifetime caused by degradation has a great impact on the integration of PEMFC in the transportation systems. Prognostics and health management is an important way to improve performance and remaining useful life for PEMFC. This thesis proposes five degradation prognosis methods for PEMFC. The thesis considers the influence of main operating conditions including the load current, temperature, hydrogen pressure, and relative humidity on the degradation of PEMFC. The global degradation trend and reversible phenomena are analyzed on the basis of data from three PEMFC experiments conducted under different conditions of use (a fleet of 10 PEMFC vehicles and two laboratory test benches). First, the model-driven method based on unscented Kalman Filter algorithm and voltage degradation model is presented to predict the degradation of PEMFC in fuel cell electric vehicles. Then, the hybrid method based on the wavelet analysis, extreme learning machine and genetic algorithm is proposed to build the degradation model of PEMFC. To forecast the degradation of PEMFC with limited experimental data, the improved data-driven method based on the combination of the grey neural network model, the particle swarm optimization and the moving window methods, is used for developing the third model. The fourth contribution is an aging prognosis model of PEMFC operating in different conditions, by using the Backpropagation neural network and evolutionary algorithm. Finally, a degradation prognosis of PEMFC based on wavelet neural network and cuckoo search algorithm is proposed to predict the remaining useful life of PEMFC

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Peretti, Luca. "Electrical drives for application in mechatronics - Azionamenti elettrici per la meccatronica." Doctoral thesis, Università degli studi di Padova, 2008. http://hdl.handle.net/11577/3425643.

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This thesis is the result of a three-years work at the Department of Technique and Management of Industrial Systems of the University of Padova, located in Vicenza, Italy. The research concerns advanced control methodologies for electrical drives. In particular, the first part of the thesis deals with sensorless control of induction motors, in which the speed is not measured but estimated by means of a mathematical model. Among the topics, there is a corollary of the sensorless control: the compensation of PWM inverter non-linearities and the induction motor parameters estimation. The second part of the thesis deals with a strategy for the automatic seeking of the maximum torque-per-ampere ratio in synchronous reluctance motors, with extension of the theory (and practice) to other motor types. The study aims to the development of more energy-efficient controls in which motor losses are reduced with the convenient choice of the control variables. Questa tesi è frutto dei tre anni di lavoro svolto presso il Dipartimento di Tecnica e Gestione dei Sistemi Industriali dell’Università degli Studi di Padova, sito in Vicenza, Italia. Il principale filone di ricerca trattato riguarda le metodologie di controllo avanzate per azionamenti elettrici. In particolare, nella prima parte della tesi sono stati trattati i controlli sensorless per motori ad induzione, in cui la velocità del motore non è misurata ma è stimata con un modello matematico. Due degli argomenti riportati ne costituiscono un naturale corollario: la compensazione delle non linearità negli inverter PWM e la stima parametrica per motori ad induzione. La seconda parte della tesi tratta una strategia per la ricerca automatica del massimo rapporto coppia/corrente per motori sincroni a riluttanza, con estensione della teoria (e della pratica) ad altri tipi di motori. Lo studio è volto allo sviluppo di controlli più efficienti in cui le perdite del motore siano ridotte tramite opportune scelte delle variabili di controllo.

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Marone, Vittorio. "Constructing Meanings by Designing Worlds: Digital Games as Participatory Platforms for Interest-Driven Learning and Creativity." Doctoral thesis, Università degli studi di Padova, 2013. http://hdl.handle.net/11577/3423639.

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This study emerges from the observation of an increasing divide between generations: a lack of a shared ground that carries profound social, cultural, and educational implications. In particular, the broadening differences between academic and “grassroots” approaches to learning and creativity are transforming formal and informal enterprises into seemingly incommunicable realms. This clash between different (and distant) practices, inside and outside of school, is inhibiting the construction of a common language between teachers and students, and, more broadly, between generations, thus hindering the development of any educational discourse. In this study I inquired into an online participatory space in order to advance our understanding on how its participants, driven by their interest for gaming and game design, discursively constructed learning and creativity. In particular, I looked into a community dedicated to designing, sharing, and critiquing digital game levels (i.e. “mini-games”) created with LittleBigPlanet (a digital game and creative tool for the PlayStation 3 game console) and discussed in the “Forum” section of the LittleBigPlanet Central website (www.lbpcentral.com). In this qualitative study I applied a hybrid intertextual methodology based on discourse analysis, studio critique, and design process analysis to analyze discursive texts (threads/posts in the discussion forum), interactive artifacts (user-generated game levels), and constructive practices (deigning, sharing, and critiquing game levels). The findings of this study show that participants socially construct and negotiate learning and creativity by enacting specific discursive functions that entail the use of humor and specialist language and the negotiation of effort and self-appreciation. By engaging in multimodal and intertextual practices in an attentive and competent community, users create a safe social space that fosters reciprocal trust, togetherness, participation, planning, and reflectivity. By furthering our understanding of a situated interest world, this research advances our knowledge on informal participatory spaces in which learning and creativity emerge as intertwined phenomena that develop through social-constructive endeavors that spur from people’s interests and passions. Questa ricerca nasce dalla constatazione di un crescente divario tra generazioni: una mancanza di terreno comune che comporta profonde implicazioni sociali, culturali ed educative. In particolare, le differenze tra approcci formali e informali all’apprendimento e alla creatività sembrano inibire la costruzione di un linguaggio condiviso tra docenti e studenti, e, più in generale, tra generazioni, ostacolando così lo sviluppo di qualsiasi discorso educativo. In questa ricerca qualitativa ho analizzato le interazioni in uno spazio on-line informale i cui partecipanti, guidati dal loro interesse per i videogiochi e il game design, progettano, condividono, e commentano livelli di gioco digitali (cioè “mini-giochi”) creati con LittleBigPlanet (un videogioco e uno strumento creativo per la PlayStation 3) e discussi nella sezione “Forum” del sito LittleBigPlanet Central (www.lbpcentral.com). In questo studio ho utilizzato una metodologia intertestuale ibrida basata sull’analisi del discorso, sulla “studio critique”, e sull’analisi di processo nel campo del design, per analizzare i testi discorsivi (i thread/post nel forum), gli artefatti interattivi (i livelli di gioco creati dagli utenti) e le pratiche costruttive (progettare, condividere e commentare i livelli di gioco). I risultati di questa ricerca dimostrano che i partecipanti del forum costruiscono socialmente l’apprendimento e la creatività attraverso specifiche funzioni discorsive che comportano l’impiego di humor e linguaggio specialistico e la negoziazione sociale di impegno e auto-apprezzamento. Gli utenti del forum, immersi in una comunità attenta e competente, cimentandosi in pratiche multimodali e intertestuali, creano uno spazio sociale che favorisce lo sviluppo di fiducia reciproca, unità, partecipazione, pianificazione, e riflettività. Questa ricerca amplia la nostra comprensione degli spazi partecipativi informali in cui l’apprendimento e la creatività emergono come fenomeni interconnessi che si sviluppano attraverso pratiche socio-costruttive che scaturiscono dagli interessi e dalle passioni delle persone.

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Ortombina, Ludovico. "Innovative solutions for converters and motor drives oriented to smart cities and communities." Doctoral thesis, Università degli studi di Padova, 2018. http://hdl.handle.net/11577/3427192.

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Alcune aree definite dall'Unione Europea nel contesto delle smart cities and communities si fondono pienamente con i motori elettrici come, per esempio, l'efficienza energetica, le tecnologie a basse emissioni di carbonio e la mobilità. I motori elettrici sono utilizzati in molteplici applicazioni industriali e non, consumando tra il 43% e il 46% dell'energia elettrica prodotta su scala mondiale.Nonostante alcune applicazioni siano contraddistinte da dinamiche elevate, come manipolatori o macchine utensili, la maggior parte di esse sono caratterizzate da basse dinamiche in quanto facenti parte di processi industriali, per esempio pompe, compressori, ventilatori o nastri trasportatori. Si è stimato che il costo dell'intero ciclo di vita di un motore elettrico è ascrivibile per il 92% - 95% all'energia consumata, il che indurrebbe un tempo di ritorno dall'investimento per installazione di un azionamento elettrico minore di due anni. Nonostante il notevole risparmio economico e ambientale ottenibile, è piuttosto sorprendente apprendere che solo il 10% - 15% di tutti i motori industriali siano controllati da azionamenti elettrici. Per quanto riguarda le diverse tecnologie di motori elettrici, i motori sincroni a riluttanza stanno ricevendo una notevole attenzione sia da ricercatori industriali che accademici. Il crescente interesse è principalmente motivato dalle loro intrinseche caratteristiche quali l'alta efficienza, il basso costo e il basso impatto ambientale dovuto alla mancanza di magneti permanenti. Per di più, le loro caratteristiche soddisfano appieno i requisiti imposti dalle smart cities and communities e sono adatti per tutte le applicazione, caratterizzate da una bassa dinamica, viste sopra. Per questi motivi, questa tecnologia di motori può essere posta al centro dei processi di rinnovamento di quelle applicazioni. Vi è ampio consenso sul potenziale incremento delle vendite sia di azionamenti elettrici che di motori sincroni a riluttanza. I motori sincroni a riluttanza sono soggetti a una marcata saturazione magnetica, rendendo i classici modelli a parametri concentrati poco adatti. La prima parte di questa tesi riguarda lo sviluppo di un innovativo modello magnetico per motori anisotropi. Si basa su una rete neurale non tradizionale, chiamata Radial Basis Function. La sua proprietà locale rende questo tipo di rete neurale particolarmente adatta ad un addestramento durante il normale funzionamento del motore. Si propone una completa procedura di design e addestramento della stessa. In particolare vengono fatte alcune considerazione le quali permettono di definire a priori alcuni parametri della rete neurale rendendo il problema di addestramento lineare. Si descrivono due algoritmi di addestramento, il primo veloce ma computazionalmente dispendioso perciò adatto per un'implementazione offline mentre il secondo idoneo ad un addestramento online. Infine, per concludere l'identificazione parametrica del motore, si propone uno schema basato sull'iniezione di una corrente continua il quale permette di stimare la resistenza di statore indipendentemente da tutti gli altri parametri della macchina. L'indipendenza parametrica permette un notevolmente miglioramento nell'accuratezza di stima del modello magnetico ottenuto con la rete neurale. La seconda parte di questa tesi, invece, tratta il controllo del motore e come sia possibile migliorarne le performance utilizzando il modello identificato. Innanzitutto, per incrementarne l'efficienza si presenta un innovativo metodo per trovare la curva a massima coppia per corrente. La tecnica proposta lavora in stretta simbiosi con l'identificazione del modello magnetico in quanto è in grado di capire dove si trova la curva cercata rispetto all'attuale punto di lavoro sfruttando la stima locale dei flussi magnetici. Identificata la direzione di movimento, l'azionamento continuamente muove il punto di lavoro coerentemente. Infine, si propongono tre diversi controlli di corrente pensati per gestire un motore fortemente non lineare, tutti basati sul modello stimato. Il primo è un controllore proporzionale-integrale nel quale i parametri vengono modificati al variare del punto di lavoro con lo scopo di mantenere la dinamica della corrente di motore costante. Il secondo è anch'esso basato su un controllore proporzionale-integrale ma a guadagni costanti accoppiato ad un'azione di feed--forward la quale compensa tutte le non linearità presenti nella mappa magnetica. Infine, il terzo è un controllo predittivo il quale determina direttamente la posizione degli switch tali per cui la funzione di costo è minimizzata. All'interno del controllo, è inserito un vincolo sulla corrente massima e si utilizza un particolare algoritmo per ottenere un lungo orizzonte di predizione. Tutti i metodi presentati nella tesi sono stata verificati attraverso dettagliate simulazioni e prove sperimentali, eccezione fatta per il controllo predittivo il quale è stato testato attraverso simulazioni. Smart cities and communities are conjugated by European Union in different areas, including energy efficiency, low carbon technologies and mobility which are deeply merged with electric motors. Electric machines are ubiquitous in industry for a wide range of applications, consuming between 43% and 46% of all electricity that is generated in the world. Although some machines are used for high-performance applications, such as robots and machine tools, the majority are used in industrial processes for pumps, compressors, fans, conveyors, and other slower-dynamic applications. It is estimated that 92% - 95% of the life cycle costs of electric motors are associated with the energy they consume, leading to typical payback periods of < 2 years for the installation of an adjustable-speed drive. It is rather surprising to learn that, despite overwhelming evidence of the attainable savings, only 10% - 15% of all industrial motors presently use electronic adjustable speed drives. On the motor side, Synchronous Reluctance (SynR) motors are gaining lots of attention from industrial researchers and academics, due to their inherent characteristics like the high efficiency, the low cost and the low environmental footprint. Their characteristics fully meet the requirements imposed by smart cities and communities and the aforementioned low-dynamics applications, so they could be the heart of the revamping of those plants. There is wide agreement that the potential for future growth in the sales of industrial drives and SynR motors is still very substantial. SynR motors are prone to magnetic saturation, making the classic model with lumped parameters unsuitable. The main part of this thesis concerns the development of a new magnetic model for anisotropic motors, especially for SynR motors. It is based on a special kind of neural network (NN), called Radial Bases Function (RBF) NN, which is particularly advisable for an online updating due to its local property. A complete training procedure is proposed in which some considerations are done to define several NN parameters and to convert the nonlinear training problem into a linear one. Two different training algorithms are presented, the former one is fast but computationally cumbersome then suitable for an offline training while the latter one is lighter then proper for an online training. In order to complete the online parameters identification, a scheme based on a DC current injection is developed to estimate the stator resistance. An exhaustive analysis is carried out to disclose that the proposed method is independent from other motor parameters which is a strength asset in a saturable motor. An accurate stator resistance value improves in turn of the magnetic model. The second part of this dissertation deals with how to exploit an accurate magnetic model to enhance the motor control. In order to improve the efficiency of the motor, exploiting the RBF NN model and the online training algorithm, the Maximum Torque per Ampere (MTPA) curve is found. Starting from a blank NN, it is continuously online trained and a proper algorithm understands where the MTPA curve is respect to the current working point. Afterwards, the drive moves itself towards the actual MTPA. Finally, three different current control schemes tailored for anisotropic motors are presented, all based on the available NN-based magnetic model. The first one is a gain-scheduling PI control where the control gains are accordingly tuned to the working point to keep constant the control bandwidth. The second one is based on a classical PI regulator with a FF action to compensate for all the nonlinearity of magnetic maps. The third one is a constrained direct Model Predictive Control (MPC) where a long prediction horizon is achieved. In order to accomplish a long prediction horizon, the Sphere Decoding Algorithm is properly modified to make it suitable for a nonlinear system. The whole thesis was fully validated through an intensive simulation and experimental stage, except the long--horizon MPC which was tested only by simulation.

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Carraro, Matteo. "Innovative estimation and control techniques in electric drives for mechatronic applications." Doctoral thesis, Università degli studi di Padova, 2014. http://hdl.handle.net/11577/3423466.

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The research presented in this thesis involves different aspects related to advanced control methodologies and self-commissioning identification algorithms in modern electrical drives. The theoretical study and the validation of the results obtained were performed in the three years of Ph.D. at the Electric Drives Laboratory in the Department of Management and Engineering of the University of Padova, (VI) Italy. The research topics were mainly three, all related to the implementation and development of advanced controls for electric drives, aimed at a more efficient use of the electric machines in the modern mechatronic applications. The demand of electric drives capable of guarantee high-performance and flexible enough to update in real time the parameters involved in the control algorithm are the motivation of the present research, as well as the meshing or replacement of standard or obsolete control techniques with modern ones, able to fully exploit the new hardware resources. In order to contextualizes and motivate the choice of the present research in the world scenario, a comprehensive bibliographic framework can be found in the introduction of each chapter of the thesis. The part one of the thesis presents two new control architectures for Permanent Magnet Synchronous Motors, that is a type of electric machine notoriously appreciated by both academia and industry for its flexibility of use and controllability. To this aim, in Chap.2 is proposed a non-linear control algorithm for the automatic search of the Maximum Torque Per Ampere (MTPA) operating condition for Permanent Magnet Synchronous Motors with anisotropic structure, to be integrated in a conventional Field Oriented Control scheme. The exhaustive convergence and stability analysis performed in order to derive a new and original tuning method of the controller (proven by numerous experimental evidences) is definitely one of the distinguishing features in this research topic. In parallel to the first topic, for the same type of motor has been investigated and developed (first analytically and then by simulation) a speed and current Direct Predictive Control with Hierarchical decisional structure. Unlike the traditional control techniques, the proposed Direct Predictive Control with modified hierarchical control structure has a faster dynamic and the capability to impose different operating conditions aimed at the energy efficiency optimisation. The on-line execution of the algorithm required for the experimental validation, has become possible thanks to the adoption of a control platform based on FPGA logic (Chap.3). In fact, the processing speed provided by these devices, released from the execution of sequential instructions (typical of the architecture of the microprocessors), ensures an execution time of the algorithm contained in a few us. The part two of the thesis (i. e. Chap.5) presents an innovative technique of parameter identification for induction motors, capable of estimating the parameters of the equivalent inverse-Gamma electric circuit completely at standstill. As known, the saturations in the parameters of the magnetic circuit of the induction motor and the relative nonlinearities, deteriorate the performance of the standard sensored or sensorless vectorial controls. The studied self-commissioning procedure addresses and solves many problems related to the estimate of the non-linearity of the parameters, and then it can be considered as an evolution of the classical identification techniques in the literature. The practical feasibility, doubly validated by numerous experimental tests and by many finite element simulations on three different induction motors, concludes the chapter and proves definitely the method. La ricerca presentata in questa tesi coinvolge molteplici aspetti che si legano alle più recenti metodologie di controllo studiate per azionamenti elettrici di ultima generazione. Lo studio teorico e la validazione in ambito sperimentale sono il frutto del lavoro svolto nel triennio di dottorato presso il laboratorio di azionamenti elettrici del Dipartimento di Tecnica e Gestione dei Sistemi Industriali dell’Università degli Studi di Padova. I temi di ricerca trattati sono principalmente tre, tutti legati alla realizzazione e allo sviluppo di algoritmi di controllo innovativi, capaci di incrementare l’efficienza e le prestazioni delle macchine elettriche di ultima generazione per applicazioni meccatroniche. Azionamenti elettrici in grado di garantire elevate prestazioni ma sufficientemente flessibili da aggiornare in tempo reale i diversi parametri coinvolti nel algoritmo di controllo sono il filo conduttore e la motivazione della presente ricerca, così come la sostituzione di logiche di controllo standard o obsolete con nuove architetture di controllo capaci di sfruttare le più recenti innovazioni hardware. Al fine di contestualizzare e motivare la ricerca condotta nel panorama mondiale, nell’introduzione di ciascun capitolo è inserito un esaustivo inquadramento bibliograficoinerente inerente il problema affrontato. La prima parte della tesi presenta due nuove architetture di controllo per motori sincroni a magnete permanente, tipologia di macchina elettrica notoriamente apprezzata dal mondo accademico e industriale sia per la sua flessibilità d’uso che per la sua facile controllabilità. In tal senso, nel Capitolo2 è descritto e formalizzato un controllo non lineare per motori sincroni a magnete permanente anisotropi, inseribile in schemi di controllo convenzionali ad orientamento di campo per ottenere la condizione di funzionamento a massima coppia su corrente (MTPA). L’esaustiva analisi di convergenza e stabilità condotta al fine di ottenere un nuovo ed originale metodo per la sintonizzazione del regolatore (comprovato da numerose evidenze sperimentali) è sicuramente una delle caratteristiche distintive per questo ramo della ricerca. Per la stessa tipologia di motore è stato poi sviluppato un controllo predittivo a stati finiti con struttura decisionale gerarchica. A differenza delle tecniche di controllo tradizionali, la soluzione studiata garantisce una dinamica veloce e la possibilità di imporre condizioni operative diverse, volte all’ottimizzazione e all’incremento dell’efficienza energetica. L’esecuzione on-line di tale algoritmo per le verifiche sperimentali si è resa fattibile grazie all’adozione di una piattaforma di controllo basata su logica FPGA (Capitolo3), in quanto la velocità di calcolo offerta da tali dispositivi, svincolata dall’esecuzione sequenziale delle istruzioni tipica dei microprocessori, garantisce tempi di esecuzione dell’algoritmo contenuti a pochi us. Nella seconda parte della tesi (Capitolo5) è presentata un innovativa tecnica di identificazione parametrica per motori asincroni, capace di stimare i parametri del circuito equivalente a Gamma-inverso del motore asincrono, a rotore fermo. Come noto, le saturazioni del circuito magnetico della macchina e le non linearità ad esso associate deteriorano le performances nei normali controlli vettoriali sensored e soprattutto sensorless. Il metodo di identificazione parametrica studiato affronta e risolve molti problemi connessi alla stima delle non linearità dei parametri, configurandosi a tutti gli effetti come un evoluzione delle classiche tecniche di identificazione presenti in letteratura. La fattibilità pratica del metodo, validata con innumerevoli prove sperimentali e simulazioni agli elementi finiti su tre diversi motori ad induzione, conclude il capitolo e prova in modo definitivo la realizzabilità del metodo.

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15

D'Ambrosio, Luca. "AffectiveDrive: sistema di Driver Assistance basato sull’analisi di sensori inerziali e tecniche di computer vision." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2018. http://amslaurea.unibo.it/16209/.

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In questa tesi viene presentata AffectiveDrive, un’applicazione di guida sicura per iPhone che rileva manovre di guida pericolose e avvisa il guidatore in caso di comportamenti non sicuri. L’applicazione utilizza algoritmi di computer vision e machine learning per monitorare il comportamento e rilevare se il conducente è in uno stato di sonnolenza o distratto, attraverso l’analisi di dati sensoriali e la fotocamera. In particolare, nell’applicazione sviluppata vengono estratti i dati sensoriali prodotti dallo smartphone. Vengono applicate tecniche di feature extraction per sintetizzare i dati prima estratti. Successivamente, viene costruito un modello di predizione partendo da un set di dati composto da misurazioni di guida e infine viene applicato l’algoritmo Random Forest alle feature estratte per riconoscere il comportamento del guidatore, classificandolo come “sicuro” / “non sicuro”. Il rilevamento di sonnolenza e distrazione viene effettuato con il Software Development Kit AffDex, il quale, una volta rilevato un volto produce valori numerici compresi tra 0 (assente) e 100 (presente) che indicano le presenza/assenza delle situazioni prima esposte. Se AffDex produce valori che superano delle soglie preimpostate il conducente verrà avvisato attraverso un allarme sonoro.

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16

Halilovic, Amer. "Experimental Transient Behaviour Characterisation of Induction Motor fed by Variable Frequency Drives for Pump Applications." Thesis, KTH, Elektrisk energiomvandling, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-157319.

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The use of variable frequency drives in centrifugal pump applications has raised the question of how to select a drive. Clogging obstacles in waste water applications create unknown transient loads for the pump system. A sudden load increase occurrence can clog the pump if the drive cannot supply enough current to reach the motor’s torque demand. In order to select a suitable drive, an empirical approach has been implemented, investigating three different drives. Results have shown that selecting a drive with the highest possible overload capabilities, even if for a short time is most suitable. Operation in vector speed control gives the most reliable operation if an automatic parameter tuning is performed by the drive. Användningen av frekvensomriktare i centrifugalpumpar har väckt fr ågan om hur en omriktare skall väljas. Igensättande objekt i avloppsvatten kan ge upphov till transienta laster i pumpsystemen. En oförutsedd lastökning kan sätta igen pumpen om frekvensomriktaren inte kan förse motorn tillräckligt med ström för att möta momentbehovet. För att välja en lämplig omriktare har ett empiriskt tillvägag ångssätt valts i en undersökning av tre olika omriktare. Resultat har visat att det är lämpligast att välja en omriktare med högst överbelastningskapacitet, även om under en kort tid. Vektor hastighetskontroll är metoden som ger stabil körning om omriktaren f ått automatiskt ställa in motorparametrarna.

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17

Ncuti, Nobera Alain-Klaus. "Evaluation of Data-Driven Gating for 68Ga-ABY-025 PET/CT in Breast Cancer Patients." Thesis, Umeå universitet, Institutionen för fysik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-172663.

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Respiratory motion during PET acquisition degrades image quality. It is mainly the area around the thorax and abdomen which is affected. External devices do provide respiratory gating solutions but are time-consuming to set up on patients and may not always be available. A data-driven gating (DDG) method based on principal component analysis (PCA) was found to provide a reliable respiratory gating signal, discriminating the need for external gating systems with FDG, but it remains to be investigated how well it performs with other PET tracers. The HER2-targeting radiotracer 68Ga-ABY-025 is currently in phase 3 development and is aimed to develop methods to select breast cancer patients that benefit from HER2-targeted treatment. Hence, absolute quantification is important. Respiratory motion correction will be important for improved quantitative accuracy since many patients have metastases in the lower part of the lungs or the liver. DDG was applied to PET/CT list mode data retrospectively using quiescent period gating. Gated images were then compared to reconstructions without gating with a matched number of coincidences. Two iterative reconstructions were evaluated, TOF OSEM (3 iterations, 16 subsets, and a 5 mm gaussian postprocessing filter) and TOF BSREM β 400. Images were evaluated for standardized uptake value (SUV) changes for well-defined lesions in thorax and abdomen where respiratory motion is prevalent. Respiratory motion was detected in a mean 2.1 bed positions per examination. DDG application resulted in a mean increase of 12.7% in SUVmax for TOF OSEM reconstruction (p=0.0156).

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18

Kruger, Gert Lodewikus. "Implementation and evaluation of V/f and vector control in high–speed PMSM drives / Kruger G.L." Thesis, North-West University, 2011. http://hdl.handle.net/10394/7609.

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The McTronX research group, at the Potchefstroom campus of the North–West University, has been researching Active Magnetic Bearings (AMBs). A fully suspended, flywheel energy storage system (FESS) has been developed. Due to excessive unbalance on the rotor, the motor drive could not be tested up to its rated speed. In the interim, until the rotor can be balanced and other rotor dynamic effects have been investigated, the group decided that the existing drive control should be improved and tested on a high–speed permanent magnet synchronous motor (PMSM), using normal roller element bearings. In order to test the motor control a second (identical) PMSM, mechanically coupled to the former, operates in generator mode which serves as the torque load. Two different control algorithms, namely V/f and vector control, are designed and implemented on a rapid control prototyping system, i.e. dSPACE®. The V/f control is an open–loop, position sensorless technique, whilst the vector controller makes use of a position sensor. From the design and implementation it became clear that the vector control is more robust, in the sense that it is less sensitive on parameter variations and disturbances. It can start up reliably even under full load conditions. The V/f control is an attractive alternative to the vector control, especially in AMB systems, where it may be difficult to mount the position sensor, has to operate in a hazardous environment not suited to the sensor or could degrade the reliability of the AMB system. The cost of the position sensor is not really a concern compared to the cost of an AMB system. The V/f control is more suited to fan and pump applications, which has a low dynamic requirement. The V/f control has high startup currents and is not recommended for applications requiring a high starting torque or fast acceleration during operation. The inverter, which drives the PMSM, also had to be developed. With regard to the motor control, the effects of inverter non–idealities had to be accounted, especially for the V/f control. The implemented control algorithms were tested up to 20 krpm. Discrepancies between the expected and actual results are discussed. Overall, the controllers performed as desired. Generally, the project goals have been reached satisfactorily. Thesis (M.Ing. (Computer and Electronic Engineering))--North-West University, Potchefstroom Campus, 2011.

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19

Langner, Jens. "Event-Driven Motion Compensation in Positron Emission Tomography: Development of a Clinically Applicable Method." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2009. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-23509.

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Positron emission tomography (PET) is a well-established functional imaging method used in nuclear medicine. It allows for retrieving information about biochemical and physiological processes in vivo. The currently possible spatial resolution of PET is about 5 mm for brain acquisitions and about 8 mm for whole-body acquisitions, while recent improvements in image reconstruction point to a resolution of 2 mm in the near future. Typical acquisition times range from minutes to hours due to the low signal-to-noise ratio of the measuring principle, as well as due to the monitoring of the metabolism of the patient over a certain time. Therefore, patient motion increasingly limits the possible spatial resolution of PET. In addition, patient immobilisations are only of limited benefit in this context. Thus, patient motion leads to a relevant resolution degradation and incorrect quantification of metabolic parameters. The present work describes the utilisation of a novel motion compensation method for clinical brain PET acquisitions. By using an external motion tracking system, information about the head motion of a patient is continuously acquired during a PET acquisition. Based on the motion information, a newly developed event-based motion compensation algorithm performs spatial transformations of all registered coincidence events, thus utilising the raw data of a PET system - the so-called `list-mode´ data. For routine acquisition of this raw data, methods have been developed which allow for the first time to acquire list-mode data from an ECAT Exact HR+ PET scanner within an acceptable time frame. Furthermore, methods for acquiring the patient motion in clinical routine and methods for an automatic analysis of the registered motion have been developed. For the clinical integration of the aforementioned motion compensation approach, the development of additional methods (e.g. graphical user interfaces) was also part of this work. After development, optimisation and integration of the event-based motion compensation in clinical use, analyses with example data sets have been performed. Noticeable changes could be demonstrated by analysis of the qualitative and quantitative effects after the motion compensation. From a qualitative point of view, image artefacts have been eliminated, while quantitatively, the results of a tracer kinetics analysis of a FDOPA acquisition showed relevant changes in the R0k3 rates of an irreversible reference tissue two compartment model. Thus, it could be shown that an integration of a motion compensation method which is based on the utilisation of the raw data of a PET scanner, as well as the use of an external motion tracking system, is not only reasonable and possible for clinical use, but also shows relevant qualitative and quantitative improvement in PET imaging Die Positronen-Emissions-Tomographie (PET) ist ein in der Nuklearmedizin etabliertes funktionelles Schnittbildverfahren, das es erlaubt Informationen über biochemische und physiologische Prozesse in vivo zu erhalten. Die derzeit erreichbare räumliche Auflösung des Verfahrens beträgt etwa 5 mm für Hirnaufnahmen und etwa 8 mm für Ganzkörperaufnahmen, wobei erste verbesserte Bildrekonstruktionsverfahren eine Machbarkeit von 2 mm Auflösung in Zukunft möglich erscheinen lassen. Durch das geringe Signal/Rausch-Verhältnis des Messverfahrens, aber auch durch die Tatsache, dass der Stoffwechsel des Patienten über einen längeren Zeitraum betrachtet wird, betragen typische PET-Aufnahmezeiten mehrere Minuten bis Stunden. Dies hat zur Folge, dass Patientenbewegungen zunehmend die erreichbare räumliche Auflösung dieses Schnittbildverfahrens limitieren. Eine Immobilisierung des Patienten zur Reduzierung dieser Effekte ist hierbei nur bedingt hilfreich. Es kommt daher zu einer relevanten Auflösungsverschlechterung sowie zu einer Verfälschung der quantifizierten Stoffwechselparameter. Die vorliegende Arbeit beschreibt die Nutzbarmachung eines neuartigen Bewegungskorrekturverfahrens für klinische PET-Hirnaufnahmen. Mittels eines externen Bewegungsverfolgungssystems wird während einer PET-Untersuchung kontinuierlich die Kopfbewegung des Patienten registriert. Anhand dieser Bewegungsdaten führt ein neu entwickelter event-basierter Bewegungskorrekturalgorithmus eine räumliche Korrektur aller registrierten Koinzidenzereignisse aus und nutzt somit die als &quot;List-Mode&quot; bekannten Rohdaten eines PET Systems. Für die Akquisition dieser Daten wurden eigens Methoden entwickelt, die es erstmals erlauben, diese Rohdaten von einem ECAT Exact HR+ PET Scanner innerhalb eines akzeptablen Zeitraumes zu erhalten. Des Weiteren wurden Methoden für die klinische Akquisition der Bewegungsdaten sowie für die automatische Auswertung dieser Daten entwickelt. Ebenfalls Teil der Arbeit waren die Entwicklung von Methoden zur Integration in die klinische Routine (z.B. graphische Nutzeroberflächen). Nach der Entwicklung, Optimierung und Integration der event-basierten Bewegungskorrektur für die klinische Nutzung wurden Analysen anhand von Beispieldatensätzen vorgenommen. Es zeigten sich bei der Auswertung sowohl der qualitativen als auch der quantitativen Effekte deutliche Änderungen. In qualitativer Hinsicht wurden Bildartefakte eliminiert; bei der quantitativen Auswertung einer FDOPA Messung zeigte sich eine revelante Änderung der R0k3 Einstromraten eines irreversiblen Zweikompartment-Modells mit Referenzgewebe. Es konnte somit gezeigt werden, dass eine Integration einer Bewegungskorrektur unter Zuhilfenahme der Rohdaten eines PET Systems sowie unter Nutzung eines externen Verfolgungssystems nicht nur sinnvoll und in der klinischen Routine machbar ist, sondern auch zu maßgeblichen qualitativen und quantitativen Verbesserungen in der PET-Bildgebung beitragen kann

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20

Langner, Jens. "Event-Driven Motion Compensation in Positron Emission Tomography: Development of a Clinically Applicable Method." Doctoral thesis, Forschungszentrum Dresden-Rossendorf e.V, 2008. https://tud.qucosa.de/id/qucosa%3A25077.

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Positron emission tomography (PET) is a well-established functional imaging method used in nuclear medicine. It allows for retrieving information about biochemical and physiological processes in vivo. The currently possible spatial resolution of PET is about 5 mm for brain acquisitions and about 8 mm for whole-body acquisitions, while recent improvements in image reconstruction point to a resolution of 2 mm in the near future. Typical acquisition times range from minutes to hours due to the low signal-to-noise ratio of the measuring principle, as well as due to the monitoring of the metabolism of the patient over a certain time. Therefore, patient motion increasingly limits the possible spatial resolution of PET. In addition, patient immobilisations are only of limited benefit in this context. Thus, patient motion leads to a relevant resolution degradation and incorrect quantification of metabolic parameters. The present work describes the utilisation of a novel motion compensation method for clinical brain PET acquisitions. By using an external motion tracking system, information about the head motion of a patient is continuously acquired during a PET acquisition. Based on the motion information, a newly developed event-based motion compensation algorithm performs spatial transformations of all registered coincidence events, thus utilising the raw data of a PET system - the so-called `list-mode´ data. For routine acquisition of this raw data, methods have been developed which allow for the first time to acquire list-mode data from an ECAT Exact HR+ PET scanner within an acceptable time frame. Furthermore, methods for acquiring the patient motion in clinical routine and methods for an automatic analysis of the registered motion have been developed. For the clinical integration of the aforementioned motion compensation approach, the development of additional methods (e.g. graphical user interfaces) was also part of this work. After development, optimisation and integration of the event-based motion compensation in clinical use, analyses with example data sets have been performed. Noticeable changes could be demonstrated by analysis of the qualitative and quantitative effects after the motion compensation. From a qualitative point of view, image artefacts have been eliminated, while quantitatively, the results of a tracer kinetics analysis of a FDOPA acquisition showed relevant changes in the R0k3 rates of an irreversible reference tissue two compartment model. Thus, it could be shown that an integration of a motion compensation method which is based on the utilisation of the raw data of a PET scanner, as well as the use of an external motion tracking system, is not only reasonable and possible for clinical use, but also shows relevant qualitative and quantitative improvement in PET imaging. Die Positronen-Emissions-Tomographie (PET) ist ein in der Nuklearmedizin etabliertes funktionelles Schnittbildverfahren, das es erlaubt Informationen über biochemische und physiologische Prozesse in vivo zu erhalten. Die derzeit erreichbare räumliche Auflösung des Verfahrens beträgt etwa 5 mm für Hirnaufnahmen und etwa 8 mm für Ganzkörperaufnahmen, wobei erste verbesserte Bildrekonstruktionsverfahren eine Machbarkeit von 2 mm Auflösung in Zukunft möglich erscheinen lassen. Durch das geringe Signal/Rausch-Verhältnis des Messverfahrens, aber auch durch die Tatsache, dass der Stoffwechsel des Patienten über einen längeren Zeitraum betrachtet wird, betragen typische PET-Aufnahmezeiten mehrere Minuten bis Stunden. Dies hat zur Folge, dass Patientenbewegungen zunehmend die erreichbare räumliche Auflösung dieses Schnittbildverfahrens limitieren. Eine Immobilisierung des Patienten zur Reduzierung dieser Effekte ist hierbei nur bedingt hilfreich. Es kommt daher zu einer relevanten Auflösungsverschlechterung sowie zu einer Verfälschung der quantifizierten Stoffwechselparameter. Die vorliegende Arbeit beschreibt die Nutzbarmachung eines neuartigen Bewegungskorrekturverfahrens für klinische PET-Hirnaufnahmen. Mittels eines externen Bewegungsverfolgungssystems wird während einer PET-Untersuchung kontinuierlich die Kopfbewegung des Patienten registriert. Anhand dieser Bewegungsdaten führt ein neu entwickelter event-basierter Bewegungskorrekturalgorithmus eine räumliche Korrektur aller registrierten Koinzidenzereignisse aus und nutzt somit die als &quot;List-Mode&quot; bekannten Rohdaten eines PET Systems. Für die Akquisition dieser Daten wurden eigens Methoden entwickelt, die es erstmals erlauben, diese Rohdaten von einem ECAT Exact HR+ PET Scanner innerhalb eines akzeptablen Zeitraumes zu erhalten. Des Weiteren wurden Methoden für die klinische Akquisition der Bewegungsdaten sowie für die automatische Auswertung dieser Daten entwickelt. Ebenfalls Teil der Arbeit waren die Entwicklung von Methoden zur Integration in die klinische Routine (z.B. graphische Nutzeroberflächen). Nach der Entwicklung, Optimierung und Integration der event-basierten Bewegungskorrektur für die klinische Nutzung wurden Analysen anhand von Beispieldatensätzen vorgenommen. Es zeigten sich bei der Auswertung sowohl der qualitativen als auch der quantitativen Effekte deutliche Änderungen. In qualitativer Hinsicht wurden Bildartefakte eliminiert; bei der quantitativen Auswertung einer FDOPA Messung zeigte sich eine revelante Änderung der R0k3 Einstromraten eines irreversiblen Zweikompartment-Modells mit Referenzgewebe. Es konnte somit gezeigt werden, dass eine Integration einer Bewegungskorrektur unter Zuhilfenahme der Rohdaten eines PET Systems sowie unter Nutzung eines externen Verfolgungssystems nicht nur sinnvoll und in der klinischen Routine machbar ist, sondern auch zu maßgeblichen qualitativen und quantitativen Verbesserungen in der PET-Bildgebung beitragen kann.

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21

Salvatori, Giada. "riconoscimento del guidatore attraverso la fotocamera frontale di uno smartphone." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2018. http://amslaurea.unibo.it/16143/.

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Nowadays car manufactures and others are investing more and more in the use of technologies in order to improve road safety. The purpose of this study is to succeed in creating a model, exploiting Machine Learning, in order to verify whether users, while they are operating their own smartphones, are driving or not, carrying out the identification through images obtainable by means of the front-facing camera of the device. We intend to illustrate different types of checks on drivers and the reason why we have chosen to develop this theory; the techniques adopted and the problems encountered during its development, detailing, step by step, the project implementation and explaining the implementation decisions, providing also varations in the development and a demo for observing the results in an active way.

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22

Soldati, Nicola. "Novel data-driven analysis methods for real-time fMRI and simultaneous EEG-fMRI neuroimaging." Doctoral thesis, University of Trento, 2012. http://eprints-phd.biblio.unitn.it/842/1/Soldati_PhD_thesis.pdf.

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Real-time neuroscience can be described as the use of neuroimaging techniques to extract and evaluate brain activations during their ongoing development. The possibility to track these activations opens the doors to new research modalities as well as practical applications in both clinical and everyday life. Moreover, the combination of different neuroimaging techniques, i.e. multimodality, may reduce several limitations present in each single technique. Due to the intrinsic difficulties of real-time experiments, in order to fully exploit their potentialities, advanced signal processing algorithms are needed. In particular, since brain activations are free to evolve in an unpredictable way, data-driven algorithms have the potentials of being more suitable than model-driven ones. In fact, for example, in neurofeedback experiments brain activation tends to change its properties due to training or task eects thus evidencing the need for adaptive algorithms. Blind Source Separation (BSS) methods, and in particular Independent Component Analysis (ICA) algorithms, are naturally suitable to such kind of conditions. Nonetheless, their applicability in this framework needs further investigations. The goals of the present thesis are: i) to develop a working real-time set up for performing experiments; ii) to investigate different state of the art ICA algorithms with the aim of identifying the most suitable (along with their optimal parameters), to be adopted in a real-time MRI environment; iii) to investigate novel ICA-based methods for performing real-time MRI neuroimaging; iv) to investigate novel methods to perform data fusion between EEG and fMRI data acquired simultaneously. The core of this thesis is organized around four "experiments", each one addressing one of these specic aims. The main results can be summarized as follows. Experiment 1: a data analysis software has been implemented along with the hardware acquisition set-up for performing real-time fMRI. The set-up has been developed with the aim of having a framework into which it would be possible to test and run the novel methods proposed to perform real-time fMRI. Experiment 2: to select the more suitable ICA algorithm to be implemented in the system, we investigated theoretically and compared empirically the performance of 14 different ICA algorithms systematically sampling different growing window lengths, model order as well as a priori conditions (none, spatial or temporal). Performance is evaluated by computing the spatial and temporal correlation to a target component of brain activation as well as computation time. Four algorithms are identied as best performing without prior information (constrained ICA, fastICA, jade-opac and evd), with their corresponding parameter choices. Both spatial and temporal priors are found to almost double the similarity to the target at not computation costs for the constrained ICA method. Experiment 3: the results and the suggested parameters choices from experiment 2 were implemented to monitor ongoing activity in a sliding-window approach to investigate different ways in which ICA-derived a priori information could be used to monitor a target independent component: i) back-projection of constant spatial information derived from a functional localizer, ii) dynamic use of temporal , iii) spatial, or both iv) spatial-temporal ICA constrained data. The methods were evaluated based on spatial and/or temporal correlation with the target IC component monitored, computation time and intrinsic stochastic variability of the algorithms. The results show that the back-projection method offers the highest performance both in terms of time course reconstruction and speed. This method is very fast and effective as far as the monitored IC has a strong and well defined behavior, since it relies on an accurate description of the spatial behavior. The dynamic methods oer comparable performances at cost of higher computational time. In particular the spatio-temporal method performs comparably in terms of computational time to back-projection, offering more variable performances in terms of reconstruction of spatial maps and time courses. Experiment 4: finally, Higher Order Partial Least Square based method combined with ICA is proposed and investigated to integrate EEG-fMRI data acquired simultaneously. This method showed to be promising, although more experiments are needed.

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23

Schneider, Stephanie Michelle Romy. "Love, hatred and indifference in chimpanzees: Personality, Subjective Well-Being, and dyadic-level behavior in captive chimpanzees (Pan troglodytes): Does something more than rank, age and sex drive the nature of interpersonal relationships in chimpanzees?" Diss., The University of Arizona, 2014. http://hdl.handle.net/10150/325003.

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This dissertation consists of two studies: the first focuses on reliability of chimpanzee personality and subjective well-being (SWB) scores, the second on validating those scores by comparing them to subjective assessments of behavior in dyads. The first measured reliability of scores of personality and subjective well-being (SWB) across ten years. Dominance rank, and the Dominance and Extraversion Factors significantly correlated between time points. In the second study, I investigated the impact of personality, SWB, and demographic characteristics on individual variation in dyadic-level individual behavior. Age predicted likeability in females, and age and rank predicted likeability in males. Neither personality factors nor SWB were correlated to likeability. An Affable domain scale and an Agonistic domain scale were constructed from the personality items. The Affable domain scale correlated with chimpanzees who were scored high neutral in social interactions, and the agonistic scale correlated with low neutral score in social interactions.

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24

Sorano, Danilo. "Studio e Progettazione di un Framework di Accesso a Database per Micro-servizi Jolie." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2017.

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La memorizzazione e gestione di dati è stato, sin dagli albori, un problema focale per l'informatica. La soluzione a questo problema si è presentata attraverso i database, che possono essere definiti come insieme di dati memorizzati all 'interno di un calcolatore elettronico a cui è possibile accedere allo scopo di effettuarne la lettura o la modifica. I database necessitano di interagire con le applicazioni per svolgere i loro processi di memorizzazione e gestione dei dati. Le soluzioni adottate per gestire il meccanismo di interazione applicazione-database sono diverse. La più comune, ad esempio per il linguaggio Java è quella di utilizzare delle API come JDBC per i database relazionali o MongoDB Java Driver per i database MongoDB. Soluzioni più complesse, ma che sicuramente semplificano il lavoro dello sviluppatore si basano sul sistema "Object/Relational Mapping", il quale realizza una mappatura tra un linguaggio orientato agli oggetti e un database relazionale. La tesi descrive design ed implementazione del tool Jolie Database Manager (JDM), pensato per semplificare l'interazione tra database SQL/no-SQL ed un micro-servizio Jolie. L'idea di base prende spunto dal sistema ORM: viene effettuata una mappatura tra i tipi Jolie ed i tipi del database, permettendo cosi di eseguire delle operazioni CRUD senza dover scrivere manualmente le query.

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25

Martí, Juan Gerard. "Data-driven methods to characterize heterogeneity in Alzheimer’s disease using cross-sectional and longitudinal data." Doctoral thesis, Universitat Pompeu Fabra, 2021. http://hdl.handle.net/10803/671269.

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Alzheimer's disease (AD), the most common form of dementia, is an incurable neurodegenerative disease that affects millions of elderly people worldwide. Detecting the disease in its early stages is the key for a more effective treatment. AD is a multifactorial disease, where several biomarkers represent different pathophysiological processes in the brain, with distinct progression paths over time. Methods to facilitate the integration and interpretation of longitudinal, heterogeneous medical data could be of benefit for a better understanding of the disease and its progression. In this thesis, we present statistical and machine learning methods and studies for early detection and to assess disease progression. Contributions of this thesis are as follows: First, we present a review on machine learning applications in AD using longitudinal neuroimaging data: we analyze their approach to typical challenges in longitudinal data analysis and show that machine learning methods using this type of data have potential to improve disease progression modelling and computer-aided diagnosis. Our second contribution is a study of AD subtyping using novel plasma-based blood biomarkers. We used a multivariate, unsupervised multiple kernel learning method over blood-based biomarkers to find subgroups of patients defined by distinctive blood biomarker profiles, and we analyze those subgroups using cross-sectional and longitudinal neuroimaging data. Our third contribution is a novel method based on recurrent, multimodal variational autoencoders to model the progression of the disease. It can use a variable number of modalities and time-points across different subjects, and we show its performance quantitatively and qualitatively. Our fourth and final contribution is an analysis of the impact of APOE ε4 gene dose and its association with age on hippocampal shape, assessed with multivariate surface analysis, using a cognitive healthy, ε4-enriched cohort. La malaltia d'Alzheimer, o simplement Alzheimer, és una malaltia neurodegenerativa incurable que afecta milions de persones a tot el món. La detecció de la malaltia en els seus primers estadis és clau per a un tractament més eficaç. L’Alzheimer és una malaltia multifactorial, on diversos marcadors representen processos fisiopatològics diferents al cervell, amb diferents tipus de progressió al llarg del temps. Mètodes per facilitar la integració i la interpretació de dades mèdiques longitudinals i heterogènies poden ser útils per aconseguir una millor comprensió de la malaltia i la seva progressió. En aquesta tesi presentem mètodes estadístics i d’aprenentatge automàtic per a la detecció precoç i per avaluar la progressió de la malaltia. Les contribucions d’aquesta tesi són les següents: En primer lloc, presentem una revisió de mètodes d’aprenentatge automàtic aplicats a l'Alzheimer que utilitza dades de neuroimatge longitudinals: analitzem el seu enfocament als desafiaments típics en l’anàlisi d'aquestes dades i demostrem que els mètodes d’aprenentatge automàtic que utilitzen dades longitudinals tenen potencial per a millorar la modelització de la progressió de la malaltia i el diagnòstic assistit per ordinador. La nostra segona contribució és un estudi de subtipatge de l'Alzheimer mitjançant biomarcadors sanguinis basats en plasma. Utilitzem un mètode multivariat i no supervisat en biomarcadors sanguinis per trobar subgrups de pacients definits per perfils distintius d'aquests biomarcadors, i analitzem aquests subgrups utilitzant dades de neuroimatge transversal i longitudinal. La nostra tercera contribució és un mètode basat en "recurrent variational autoencoders", un tipus de xarxa neuronal, per modelar la progressió de la malaltia. El mètode utilitza un nombre variable de modalitats i adquisicions en diferents pacients, i mostrem el seu rendiment quantitativament i qualitativament. La nostra quarta i última contribució és una anàlisi de l’impacte del gen APOE ε4 i la seva associació amb l’edat en la superfície de l’hipocamp, evaluada amb un anàlisi multivariat sobre una cohort amb alta proporció de pacients sans amb el gen ε4.

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26

Narayanan, G. "Synchronised Pulsewidth Modulation Strategies Based On Space Vector Approach For Induction Motor Drives." Thesis, Indian Institute of Science, 1999. https://etd.iisc.ac.in/handle/2005/139.

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In high power induction motor drives, the switching frequency of the inverter is quite low due to the high losses in the power devices. Real-time PWM strategies, which result in reduced harmonic distortion under low switching frequencies and have maximum possible DC bus utilisation, are developed for such drives in the present work. The space vector approach is taken up for the generation of synchronised PWM waveforms with 3-Phase Symmetry, Half Wave Symmetry and Quarter Wave Symmetry, required for high-power drives. Rules for synchronisation and the waveform symmetries are brought out. These rules are applied to the conventional and modified forms of space vector modulation, leading to the synchronised conventional space vector strategy and the Basic Bus Clamping Strategy-I, respectively. Further, four new synchronised, bus-clamping PWM strategies, namely Asymmetric Zero-Changing Strategy, Boundary Sampling Strategy-I, Basic Bus Clamping Strategy-II and Boundary Sampling Strategy-II, are proposed. These strategies exploit the flexibilities offered by the space vector approach like double-switching of a phase within a subcycle, clamping of two phases within a subcycle etc. It is shown that the PWM waveforms generated by these strategies cannot be generated by comparing suitable 3-phase modulating waves with a triangular carrier wave. A modified two-zone approach to overmodulation is proposed. This is applied to the six synchronised PWM strategies, dealt with in the present work, to extend the operation of these strategies upto the six-step mode. Linearity is ensured between the magnitude of the reference and the fundamental voltage generated in the whole range of modulation upto the six-step mode. This is verified experimentally. A suitable combination of these strategies leads to a significant reduction in the harmonic distortion of the drive at medium and high speed ranges over the conventional space vector strategy. This reduction in harmonic distortion is demonstrated, theoretically as well as experimentally, on a constant V/F drive of base frequency 50Hz for three values of maximum switching frequency of the inverter, namely 450Hz, 350Hz and 250Hz. Based on the notion of stator flux ripple, analytical closed-form expressions are derived for the harmonic distortion due to the different PWM strategies. The values of harmonic distortion, computed based on these analytical expressions, compare well with those calculated based on Fourier analysis and those measured experimentally.

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27

Narayanan, G. "Synchronised Pulsewidth Modulation Strategies Based On Space Vector Approach For Induction Motor Drives." Thesis, Indian Institute of Science, 1999. http://hdl.handle.net/2005/139.

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In high power induction motor drives, the switching frequency of the inverter is quite low due to the high losses in the power devices. Real-time PWM strategies, which result in reduced harmonic distortion under low switching frequencies and have maximum possible DC bus utilisation, are developed for such drives in the present work. The space vector approach is taken up for the generation of synchronised PWM waveforms with 3-Phase Symmetry, Half Wave Symmetry and Quarter Wave Symmetry, required for high-power drives. Rules for synchronisation and the waveform symmetries are brought out. These rules are applied to the conventional and modified forms of space vector modulation, leading to the synchronised conventional space vector strategy and the Basic Bus Clamping Strategy-I, respectively. Further, four new synchronised, bus-clamping PWM strategies, namely Asymmetric Zero-Changing Strategy, Boundary Sampling Strategy-I, Basic Bus Clamping Strategy-II and Boundary Sampling Strategy-II, are proposed. These strategies exploit the flexibilities offered by the space vector approach like double-switching of a phase within a subcycle, clamping of two phases within a subcycle etc. It is shown that the PWM waveforms generated by these strategies cannot be generated by comparing suitable 3-phase modulating waves with a triangular carrier wave. A modified two-zone approach to overmodulation is proposed. This is applied to the six synchronised PWM strategies, dealt with in the present work, to extend the operation of these strategies upto the six-step mode. Linearity is ensured between the magnitude of the reference and the fundamental voltage generated in the whole range of modulation upto the six-step mode. This is verified experimentally. A suitable combination of these strategies leads to a significant reduction in the harmonic distortion of the drive at medium and high speed ranges over the conventional space vector strategy. This reduction in harmonic distortion is demonstrated, theoretically as well as experimentally, on a constant V/F drive of base frequency 50Hz for three values of maximum switching frequency of the inverter, namely 450Hz, 350Hz and 250Hz. Based on the notion of stator flux ripple, analytical closed-form expressions are derived for the harmonic distortion due to the different PWM strategies. The values of harmonic distortion, computed based on these analytical expressions, compare well with those calculated based on Fourier analysis and those measured experimentally.

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28

Cavallin, Riccardo. "Approccio blockchain per la gestione dei dati personali." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2020. http://amslaurea.unibo.it/21604/.

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L'elaborato presenta la tecnologia blockchain nelle sue funzionalità e nei suoi limiti. In particolare sono presentate le piattaforme Ethereum, RadixDLT e IOTA. Vengono discusse le implicazioni del regolamento GDPR nei confronti di questa tecnologia per la costruzione di Data Marketplace basato su Ethereum. Dopo aver presentato l'architettura di un marketplace si analizzano le prestazioni di diversi servizi di storage online per l'archiviazione di dati personali.

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29

FORNASARI, ELEONORA CLAUDIA MIRELLA. "PICCOLE DONNE CRESCONO: STORIE AL FEMMINILE DALLA LETTERATURA PER L'INFANZIA ALLA SERIALITA' TELEVISIVA. TRE CASE STUDIES." Doctoral thesis, Università Cattolica del Sacro Cuore, 2018. http://hdl.handle.net/10280/42961.

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La presente tesi di dottorato ha come oggetto la trasposizione televisiva di tre romanzi character driven: Heidi, Pippi Calzelunghe e The Story of Tracy Beaker. Questi, analizzati soprattutto dal punto di vista della protagonista femminile, sono stati studiati, così come i relativi adattamenti, utilizzando un modello metodologico di analisi che poggia le sue basi teoriche sia nell'estetica della letteratura per ragazzi sia nelle teorie dell'adattamento e della sceneggiatura. Il mercato audiovisivo e la tipologia di spettatori cambiano rapidamente e ciò rende necessaria un'attualizzazione non solo tematica, ma anche stilistica dell'opera originaria, alla ricerca di un compromesso tra la fedeltà al testo iniziale, necessaria per permettere al target l'immediata riconoscibilità dell'opera e dei personaggi, e l'esigenza di rispettare le richieste della contemporaneità. A livello accademico, lo studio degli adattamenti della letteratura per l'infanzia si è concentrato quasi esclusivamente in ambito cinematografico e non televisivo, nonostante quest'ultimo fornisca molti spunti di riflessione tanto sul processo di adattamento in sé quanto sulla serialità. Il presente lavoro si propone perciò di andare a riempire il gap teorico sull'argomento, ponendosi necessariamente a cavallo di due ambiti, -la letteratura e l'audiovisivo. Di conseguenza, l'approccio privilegiato è più letterario che pedagogico e si interseca con gli studi sull'adattamento e sull'industria audiovisiva. This PhD dissertation investigates the adaptations from children's novels into television series, with a focus on three character-driven stories: Heidi, Pippi Longstockings and The Story of Tracy Beaker. Starting from the original novels, investigated mostly from the point of view of the female protagonist, the study then analyses the corresponding television adaptations, whether animated or live action, through a methodology that has its theoretical basis both in the aesthetics of children's literature and in the screenwriting theories. Nowadays, the audiovisual market and therefore the public are changing rapidly, making it necessary to update the thematic and the stylistic features of the original works from which the adaptations are drawn. Actually, adaptation is often a compromise between the contemporary market demand and the fidelity to the content, necessary to fulfil the expectations of the target audience. Surprisingly, there is a scarcity of critical literature on children's television adaptations, even if they represent a very rich topic as they raise specific issues both on the adaptation process itself and on serialisation. The present work, therefore, aims to fill the existing gap in the field of children's adaptations, placing itself where two critical areas, literature and media, meet. Consequently, the primary narrative approach intersects with studies on adaptation and audiovisual industry.

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30

FORNASARI, ELEONORA CLAUDIA MIRELLA. "PICCOLE DONNE CRESCONO: STORIE AL FEMMINILE DALLA LETTERATURA PER L'INFANZIA ALLA SERIALITA' TELEVISIVA. TRE CASE STUDIES." Doctoral thesis, Università Cattolica del Sacro Cuore, 2018. http://hdl.handle.net/10280/42961.

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La presente tesi di dottorato ha come oggetto la trasposizione televisiva di tre romanzi character driven: Heidi, Pippi Calzelunghe e The Story of Tracy Beaker. Questi, analizzati soprattutto dal punto di vista della protagonista femminile, sono stati studiati, così come i relativi adattamenti, utilizzando un modello metodologico di analisi che poggia le sue basi teoriche sia nell'estetica della letteratura per ragazzi sia nelle teorie dell'adattamento e della sceneggiatura. Il mercato audiovisivo e la tipologia di spettatori cambiano rapidamente e ciò rende necessaria un'attualizzazione non solo tematica, ma anche stilistica dell'opera originaria, alla ricerca di un compromesso tra la fedeltà al testo iniziale, necessaria per permettere al target l'immediata riconoscibilità dell'opera e dei personaggi, e l'esigenza di rispettare le richieste della contemporaneità. A livello accademico, lo studio degli adattamenti della letteratura per l'infanzia si è concentrato quasi esclusivamente in ambito cinematografico e non televisivo, nonostante quest'ultimo fornisca molti spunti di riflessione tanto sul processo di adattamento in sé quanto sulla serialità. Il presente lavoro si propone perciò di andare a riempire il gap teorico sull'argomento, ponendosi necessariamente a cavallo di due ambiti, -la letteratura e l'audiovisivo. Di conseguenza, l'approccio privilegiato è più letterario che pedagogico e si interseca con gli studi sull'adattamento e sull'industria audiovisiva. This PhD dissertation investigates the adaptations from children's novels into television series, with a focus on three character-driven stories: Heidi, Pippi Longstockings and The Story of Tracy Beaker. Starting from the original novels, investigated mostly from the point of view of the female protagonist, the study then analyses the corresponding television adaptations, whether animated or live action, through a methodology that has its theoretical basis both in the aesthetics of children's literature and in the screenwriting theories. Nowadays, the audiovisual market and therefore the public are changing rapidly, making it necessary to update the thematic and the stylistic features of the original works from which the adaptations are drawn. Actually, adaptation is often a compromise between the contemporary market demand and the fidelity to the content, necessary to fulfil the expectations of the target audience. Surprisingly, there is a scarcity of critical literature on children's television adaptations, even if they represent a very rich topic as they raise specific issues both on the adaptation process itself and on serialisation. The present work, therefore, aims to fill the existing gap in the field of children's adaptations, placing itself where two critical areas, literature and media, meet. Consequently, the primary narrative approach intersects with studies on adaptation and audiovisual industry.

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31

Sacchetti, Giacomo. "L’impatto degli Analytics: come i Big Data stanno cambiando le aziende." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2022.

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In questa tesi affronto il mondo dei big data e di come stanno avendo impatto sulle aziende. Vengono affrontati casi di studio come Cambridge Analytica, le elezioni Americane del 2016 e la Brexit. Si affronta anche vari aspetti di gestione e estrazione dei dati negli algoritmi di suggestione dei vari provider di servizi, quali netflix, amazon etc...

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32

BESANA, Francesco. "Heat Rejection Problematic in SolarCombi+ System." Doctoral thesis, Università degli studi di Bergamo, 2010. http://hdl.handle.net/10446/607.

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Un impianto SolarCombi+ è costituito da collettori solari termici, accumulo di acqua calda, macchina frigorifera attivata termicamente, torre di smaltimento del calore, pompe e sistema di distribuzione. Un impianto di questo tipo è in grado di soddisfare la domanda di riscaldamento, raffrescamento dei locali e per la produzione di acqua calda sanitaria. L’uso combinato dell’energia solare per il riscaldamento e il raffrescamento dei locali ha la potenzialità di elevare la tecnologia del solare termico dalla sola produzione dell’acqua calda sanitaria alla copertura di un maggior fabbisogno di energia termica. Fino ad oggi la tecnologia delle macchine frigorifere attivate termicamente era disponibile solamente per impianti di grossa taglia. Le nuove macchine frigorifere di piccola taglia stanno cercando di aprire il mercato per le piccole applicazioni che in Europa costituiscono la maggior parte della domanda di riscaldamento e della crescente domanda di raffrescamento. Per questo motivo, con la promozione dei sistemi SolarCombi+ di piccola taglia, le attività di ricerca stanno contribuendo considerevolmente al raggiungimento dell’importante obbiettivo della politica energetica dell’unione europea; in particolare quello legate alla quota di energia da fonti rinnovabili e alla sicurezza della fornitura di energia nella unione europea. Il potenziale di riduzione del consumo di combustibile fossile associato alla maggior conoscenza delle tecnologie per le energie rinnovabili è stata la spinta a sostenere questo lavoro di tesi. In this study, firstly heat rejection components has been treated and then the entire SolarCombi+ model has been developed in order to help the design and control of such system. These components are in form of mathematical models, TRNSYS type, and guidelines for design and control are produced from results of numerously dynamic simulations applied to the entire SolarCombi+ system. A SolarCombi+ plant consists of solar collectors, hot water storage buffer, heat Thermally Driven Chiller, cooling tower, pumps, and distribution system so as to satisfy the space heating and cooling and, domestic hot water preparation. The combined use of solar energy for heating and cooling has the potential to upgrade solar thermal energy from mainly DHW provider to a major building energy supplier. Up to now thermally driven chillers were only available in higher power range. The new small scale sorption chillers are trying to open the market for small applications, which make up for the major part of heating and a constantly growing part of cooling demand in Europe. Thus, promoting small scale SolarCombi+ systems, the research activities will contribute considerably to achieving important energy policy goals of the European Union; in particular relating to the share of renewable energies and the security of energy supply in the EU. The potential for reduction in fossil fuel consumption associated with a better knowledge of renewable energy technologies provides the impetus for this project.

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33

Folkesson, Anders. "Towards sustainable urban transportation : Test, demonstration and development of fuel cell and hybrid-electric buses." Doctoral thesis, KTH, Energiprocesser, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4721.

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Several aspects make today’s transport system non-sustainable: • Production, transport and combustion of fossil fuels lead to global and local environmental problems. • Oil dependency in the transport sector may lead to economical and political instability. • Air pollution, noise, congestion and land-use may jeopardise public health and quality of life, especially in urban areas. In a sustainable urban transport system most trips are made with public transport because high convenience and comfort makes travelling with public transport attractive. In terms of emissions, including noise, the vehicles are environmentally sustainable, locally as well as globally. Vehicles are energy-efficient and the primary energy stems from renewable sources. Costs are reasonable for all involved, from passengers, bus operators and transport authorities to vehicle manufacturers. The system is thus commercially viable on its own merits. This thesis presents the results from three projects involving different concept buses, all with different powertrains. The first two projects included technical evaluations, including tests, of two different fuel cell buses. The third project focussed on development of a series hybrid-bus with internal combustion engine intended for production around 2010. The research on the fuel cell buses included evaluations of the energy efficiency improvement potential using energy mapping and vehicle simulations. Attitudes to hydrogen fuel cell buses among passengers, bus drivers and bus operators were investigated. Safety aspects of hydrogen as a vehicle fuel were analysed and the use of hydrogen compared to electrical energy storage were also investigated. One main conclusion is that a city bus should be considered as one energy system, because auxiliaries contribute largely to the energy use. Focussing only on the powertrain is not sufficient. The importance of mitigating losses far down an energy conversion chain is emphasised. The Scania hybrid fuel cell bus showed the long-term potential of fuel cells, advanced auxiliaries and hybrid-electric powertrains, but technologies applied in that bus are not yet viable in terms of cost or robustness over the service life of a bus. Results from the EU-project CUTE show that hydrogen fuelled fuel cell buses are viable for real-life operation. Successful operation and public acceptance show that focus on robustness and cost in vehicle design were key success factors, despite the resulting poor fuel economy. Hybrid-electric powertrains are feasible in stop-and-go city operation. Fuel consumption can be reduced, comfort improved, noise lowered and the main power source downsized and operated less dynamically. The potential for design improvements due to flexible component packaging is implemented in the Scania hybrid concept bus. This bus and the framework for its hybrid management system are discussed in this thesis. The development of buses for a more sustainable urban transport should be made in small steps to secure technical and economical realism, which both are needed to guarantee commercialisation and volume of production. This is needed for alternative products to have a significant influence. Hybrid buses with internal combustion engines running on renewable fuel is tomorrow’s technology, which paves the way for plug-in hybrid, battery electric and fuel cell hybrid vehicles the day after tomorrow. QC 20100722

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34

Conti, Claudio. "Small-scale physical modelling of piled foundations for offshore wind turbines application." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2019.

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Nowadays, finding alternative energy sources is becoming more and more important. Europe is particularly focusing on wind energy and in offshore wind energy especially. An issue concerning offshore wind energy which is gaining more and more attention is the noise emissions due to impact driven pile foundation. The noise caused by the installation process has been judged as “potentially dangerous for marine fauna” from the German Authorities. This research thesis is part of a project which examines a viable alternative installation method for the displacement of pile foundations for offshore wind energy called pile jacking. This technology should be developed to be cost-efficient, flexibly scalable and to produce considerably reduced vibration and air pollution emissions during its placement in the sea bed. Jacked piles technology would eliminate almost any noise deriving from the hammer impact. As most offshore piled foundations have been installed by impact driving technology, the question arises as to how piles with different the stiffness and the capacity , can otherwise be installed. In order to delineate the significant variables affecting the load-bearing capacity and especially the ultimate uplift capacity of a pile in saturated sand, a small-scale test campaign in scale 1:30 has been performed at the Test Center for Support Structures in Hanover. The campaign was supervised by the Department for Support Structures of Fraunhofer IWES. A testing schedule comprising of 15 small-scale geotechnical physical experiments was conducted on open-ended piles to an embedded length of 75 cm using two method of pile installation: static jacking and impact driving. The aim of this thesis is to obtain preliminary experimental data and set out the main features of this technology. The results obtained by this study reveal that static jacking installation lead to higher resistances and is overall beneficial to the mechanical load bearing behavior of pile foundations.

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35

Yammine, Samer. "Contribution to the Synchronous Reluctance Machine Performance Improvement by Design Optimization and Current Harmonics Injection." Phd thesis, Toulouse, INPT, 2015. http://oatao.univ-toulouse.fr/14555/1/yammine.pdf.

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This thesis is dedicated to the evaluation and the improvement of the synchronous reluctance machine’s performance for variable speed drive applications in general and for automotive applications in particular. The two axes of development are machine design and phase current harmonics injection. The rotor is an important element in the machine design and particular emphasis is placed to the design and evaluation of the rotor for enhancing the machine performance. An analytical procedure is proposed for the rotor design. The rotor elements like the ribs and the bridges that maintain the rotor mechanically strong as well as the q-axis insulation ratio (air-to-steel ratio) are studied. A computer-aided design study based on a parametric optimization problem is presented as well. The main three families of the optimization algorithms are evaluated for the optimization procedure: a gradient-based algorithm (Quasi Newton Algorithm), a non-gradient based non-evolutionary algorithm (Nelder Mead Simplex) and a non-gradient based evolutionary algorithm (Genetic Algorithm). The machine designs based on the analytical procedure and the optimization procedure are both manufactured and tested on a bench. The second axis of study of the thesis is the injection of harmonics in the phase currents of the synchronous reluctance machine. The interaction of current harmonics with the spatial inductance harmonics is studied and formalized for an m-phase machine. Then, the harmonics injection concept is evaluated in the particular case of a 2-phase machine. This study shows the benefi t of harmonics injection in the reduction of the machine torque ripple. A synchronous reluctance machine design is fi nally developed for an automotive application based on parametric optimization of the stator and rotor. This design is evaluated for the electromagnetic specifi cations imposed by a mid-power electric vehicle traction application

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36

Tard, Céline. "Modulation corticale de la locomotion." Thesis, Lille 2, 2015. http://www.theses.fr/2015LIL2S067/document.

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Les patients atteints de maladie de Parkinson présentent des troubles de la marche, parfois paroxystiques, pouvant être aggravés ou améliorés par les stimuli environnementaux. L'attention portée, soit aux stimuli extérieurs, soit à la marche, pourrait ainsi moduler la locomotion.L’objectif principal était donc de mieux caractériser la manière dont les stimuli environnementaux modulent par le biais de réseaux attentionnels la locomotion. Ceci a été étudié chez les sujets sains puis chez les patients parkinsoniens, avec ou sans enrayage cinétique.Nous avons d'abord défini précisément les déficits attentionnels des patients, avec ou sans troubles de la marche. Ils présentaient respectivement des difficultés en flexibilité mentale et plus particulièrement en attention divisée.Nous avons ensuite exploré l'interaction attention-locomotion grâce à l'étude de la préparation motrice. Ainsi, nous avons pu démontrer que les ajustements posturaux anticipés étaient un marqueur sensible de l’attention. Chez les patients, ils pouvaient témoigner d’une altération de l'interaction attention-programmation motrice.L'étude des régions cérébrales activées lors de la locomotion visuo-guidée chez ces patients a permis de confirmer l'implication de structures corticales attentionnelles. Un déséquilibre d’activation au sein du réseau pariéto-prémoteur (nécessaire à la modulation de l'action motrice en fonction des stimuli externes) était présent.Enfin, nous avons essayé de modifier l'excitabilité du cortex prémoteur via des techniques de stimulation magnétique transcrânienne répétitive afin de moduler la locomotion visuo-guidée Patients with Parkinson 's disease present gait impairments, sometimes sudden and unexpected, either improved or deteriorated with environmental stimuli. Attention focalization, either on external stimuli or on gait, could then modulate locomotion.The main objective was to better characterize how environmental stimuli would modulate locomotion, via attentional networks, in healthy subjects and in parkinsonian patients, with or without freezing of gait.At first, we precisely defined the attentional deficits in patients, with or without gait impairment. They showed altered performance respectively in mental flexibility and in divided attention.Then, we explored the attention-locomotion interaction by studying motor preparation. So, we highlighted that anticipatory postural adjustments were a sensitive marker of attention. In patients, they evidenced an alteration of the attention-motor program interaction.Studying the brain activation during the visuo-driven locomotion in these patients confirmed the involvement of cortical attentional regions. We observed an imbalance inside the parieto-premotor network (useful to modulate motor action according external stimuli)Finally, we tried to change the excitability of the premotor cortex with transcranial magnetic stimulation to modulate visuo-driven locomotion

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37

Umbert, Morist Martí. "Expression control of singing voice synthesis: modeling pitch and dynamics with unit selection and statistical approaches." Doctoral thesis, Universitat Pompeu Fabra, 2016. http://hdl.handle.net/10803/361103.

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This thesis focuses on the control of a singing voice synthesizer to achieve natural expression similar to a real singer. There are many features that should be controlled to achieve natural expression related to melody, dynamics, rhythm, and timbre. In this thesis we focus on the control of pitch and dynamics with a unit selection-based system, two statistically-based systems, and a hybrid system. These systems are trained with two possible expression databases that we have designed, recorded, and labeled. We define the basic units from which the databases are built of, which are basically sequences of three notes or rests. Our perceptual evaluation compares the proposed systems with other systems to see how these relate to each other. The objective evaluation focuses on the algorithms efficiency. Aquesta tesi es centra en el control dels sintetitzadors de veu cantada per aconseguir una expressivitat natural semblant a la d'un cantant real. Hi ha moltes característiques que s'haurien de controlar per aconseguir una expressivitat natural relacionades amb la melodia, la dinàmica, el ritme i el timbre. En aquesta tesi ens centrem en el control de la freqüència fonamental i de la dinàmica amb un sistema basat en selecció d'unitats, dos sistemes estadístics, i un sistema híbrid. Aquests sistemes són entrenats amb dues possibles bases de dades expressives que hem dissenyat, enregistrat i etiquetat. Hem definit les unitats bàsiques a partir de les quals les bases de dades s'han construit i que són seqüències de tres notes o silencis. La nostra avaluació perceptual compara els sistemes proposats amb altres sistemes per tal de veure com els podem relacionar. L'avaluació objectiva es centra en l'eficiència dels sistemes.

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Wang, Yun Chang, and 王韻昌. "Design of Configurable USB Pen Drive." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/366r27.

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碩士 元智大學 資訊工程學系 106 As technology advances, cell of NAND flash memory scales down and approaches its physical limitation. Although capacity per cell becomes larger and larger, the number of electorns that can be accommodated in a cell becomes less and less that makes it unreliabile. On the other hand, to further reduce the storage cost, the number of bits per cell ranges from one bit, referred to as Single-Level-Cell (SLC), two bits, referred to as Multi-Level-Cell (MLC), to three bits, referred to as Triple-Level Cell (TLC), which further degrades its reliability. For vendors, how to balance cost, capacity, and reliability becomes a critical issue. In this paper, we will explore the relationship between process and capacity and difference between SLC and MLC; we also propose a configurable USB pen drive that enables users to configure their device as SLC mode or MLC mode according to their requirement.

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汪宗輝. "The Application of Integrating US-OTG Serial Interface and Pen Drive." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/65975244733635079051.

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碩士 明新科技大學 電子工程研究所 95 USB interface technology is applied to the consuming electronic product extensively. Among them, USB Pen Drive can be regarded as the most popular product. In this thesis we combine the recording and playback circuit with the USB OTG structure, hope to expand the data storage characteristic of Pen Drive and make it have the function of recording pen concurrently. The circuit in this thesis is made up of four parts mainly, including USB host controller(SL811HS)、MCU(HT46R24 AD-Type Microcontroller) 、cording/Playback circuit and Pen Drive. SL811HS is a product of Cypress, and combined the chipset host mode with HT46R24 MCU to perform device anumeration and packet transfer for USB standard. The voice is filtered/amplified by recording circuit firstly, and then digitalized via the AD interface of HT46R24. Pen Drive works as the storage media and the Ping-Pong mechanism is used to make MCU access time more flexibility. Two types of low cost DA interface are used for voice playback R-2R and PWM.In this thesis we will also discuss the advantage and disadvantage of these two ways.

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Chuang, Li-Wei, and 莊立暐. "A Pen-based plotter and the Driver Design." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/09024718676886533219.

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碩士 萬能科技大學 電資研究所 102 The thesis is to use a Pen-based plotter to realize the method of X and Y bars’ controlling, to design the driver and look further into how the plotter can simulate sketching with pencil. Following is the research procedure for reference. 1. Assemble the Pen-based plotter for understanding its electronic components. 2. Design the driver of Pen-based plotter to make it work regularly and effectively. 3. Look into Line Art graph to understand how it makes the Pen-based plotter designed. 4. Make image modeling on Matlab. 5. Create Fine Line algorithm to track lines. 6. Program the Serial Communication which is similar to G-Code, so that it can transmit large database to the Pen-based plotter. We look forward to understanding the operation way of Pen-based plotter through the thesis, and to share the bugs and solutions that I/we’ve successfully worked out during the design process.

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Min, Hao-Siang, and 閩浩翔. "The Commercialization of the Tool Pen Driver Kit through Kickstarter." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/66413694419100548400.

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碩士 國立臺灣科技大學 設計研究所 103 Designers are always excited about putting the design into production. In the traditional product development process, designers have to follow the procedure of marketing, exhibiting, and establishing the sales channel with salespersons, which needs certain investment but the result is unclear. However, the emerging crowdfunding platform is a realization opportunity for start-up designers, freeing them from shares offering or liabilities, allowing them to reward investors by products or related giveaways. This study conducted a case study on traditional hand tools by probing into the problems of existing products and trying to propose a new appealing design through a resonant solution. As a result, the Tool Pen was created by using the stacking structure of pop-a-point pencils and reinterpreting traditional driver bits tools. After the design was completed, the Tool Pen was posted on the crowdfunding platform Kickstarter. The funding preparation, web page deployment, funding operation, product manufacturing and sustaining, the troubleshooting and the management of the project were all recorded to identify critical elements in the success of crowdfunding. This study synthesized conceptual design in the front end and manufacturing in the back end, proposed a practical scheme for designers to put design into production. It could be served as a useful reference for designers willing to utilize the crowdfunding platform for the materialization of their designs.

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Shen, Yu-Chieh, and 沈郁杰. "Kinematical Analysis of Table Tennis Reverse Pen-hold and Shake-hand Grips Backhand Drives." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/79624375801497624226.

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碩士 國立臺灣師範大學 體育學系在職進修碩士班 100 The purpose of this study was to compare the kinematical variables between table tennis reverse pen-hold and the shake-hand grips backhand drive movements. Six reverse pen-hold grip and eight shake-hand grip elite table tennis players served as the participants. The players performed the backhand drives after receiving the topspin and the backspin shots from the server to hit the ball to the diagonal and the straight directions. Ten Vicon Motion Capture systems MX13+ (250Hz) were used to collect the 3D kinematics data of the participants, the kinematic parameters was calculated with the Vicon Nexus 1.4 and Visual 3D software. The data was tested by using non-parametric Mann-Whitney U at a .05 significant level and calculated by SPSS 19.0 software. The results showed: when returning backspin shots in diagonal path, the racket velocity of the shake-hand grip was greater at the contact point; the pen-hold racket took more time in the swing stage; the racket title angle of the pen-hold racket was smaller than that of the shake-hand grip. In terms of the joint angle and angular velocity, the results showed: due to the differences in elbow and wrist during swing, the pen-hold racket moved upward whereas the shake-hand grip moved forward; the hip angle of the pen-hold-racket players was less than that of the shake-hand grip players, the supination rotation angle of elbow and wrist in the shake-hand grip players was greater than that in the pen-hold-racket players at the contact point.

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Wang, Ming-Ching, and 王明清. "Mechanical Design Improvement and Research of Multi-Function Plastic Hinge for Portable Pen Driver." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/14494409831362322854.

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碩士 中原大學 機械工程研究所 100 Currently most of 3C products such as mobile phone, digital camera, digital video, notebook and electronic dictionary and so on are all used metal hinge as a rotation structure in the market, Due to its volume is too big and weight is a little heavy so that cost is higher as well. The purpose of this thesis (technical report) is in order to improve these defects and achieve the same function like metal hinge, therefore research and design a kind of pen driver with a compact plastic hinge instead of current metal hinge. The direction of research in this mechanism of plastic hinge must have rotation function from 0 to 164 angles, and it will also need the friction structure to make rotation action more stable without shaking problem when swiveling. Then its lock function is the most significant to guide users to know how to operate it conveniently when metal cover of pen driver is opened and swiveled to the immovable angle for using and it is swiveled to cover the PCB(Printed Circuit Board). The final goal in this concept of mechanism design can be applied for other products actually and can be produced in mass production smoothly. Will use CAD softwares of Pro-e/Engineer and Solidworks to do the mechanical design for details which include part separation and assembly, then use CAE softwares of ADAMS and Moldflow to do the mechanical motion and moldflow simulation before tooling is fabricated. The last step is to do some reliability test which includes rotation friction、bending and duration and so on. According to the final analysis and verification result： (1)Plastic hinge has not opened and dropped out from body when the moment of force was more than 0.528 Newton˙Meter. (2)Modified the assembly gap between the notch of top case and plastic hinge from 0.05mm to 0.02mm, the dimension of the assembly between metal cover and plastic main body is under 0.25mm (tolerance =0.3mm) after doing the verification again. (3)There is obviously friction and will not have rotation shake and drop situation when metal cover is swiveled to random angle.

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Huang, Hsiao-Ping, and 黃筱萍. "TW K-12 Academy: A Finger-driven Interact Learning System with Smart-pen Assistance on iOS Devices." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/uz9r2u.

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碩士 國立中央大學 資訊工程學系 104 Recently, with the popularity of mobile devices and the growth of wireless network, smartphones are widely used for navigating numerous important life activities. Besides, there are some video streaming technologies proposed to address the limits for watching video on the mobile devices. Therefore, there are lots of streaming application emerge currently, including educational application. However, there are no well-developed streaming based learning system for K-12 students. Consequently, we design a streaming-based learning system for K-12 students on iOS devices in order to provide them ubiquitous learning environment. We also integrate digital pen into our learning system to improve student learning efficiency in the blended learning environment. Besides, students’ learning histories, learning timetable, digital note enable synchronize between their multi-devices. They also can raise any question to teacher in our learning system.

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Feng, Yuchen. "c-Myc inactivation of p53 through the pan-cancer lncRNA MILIP drives cancer pathogenesis." Thesis, 2021. http://hdl.handle.net/1959.13/1429750.

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Research Doctorate - Doctor of Philosophy (PhD) The functions of the proto-oncoprotein c-Myc and the tumour suppressor p53 in controlling cell survival and proliferation are inextricably linked as “Yin and Yang” partners in normal cells to maintain tissue homeostasis: c-Myc induces the expression of ARF tumour suppressor (p14ARF in human and p19ARF in mouse) that binds to and inhibits mouse double minute 2 homolog (MDM2) leading to p53 activation, whereas p53 suppresses c-Myc through a combination of mechanisms involving transcriptional inactivation and microRNA-mediated repression. Nonetheless, the regulatory interactions between c-Myc and p53 are not retained by cancer cells as is evident from the often-imbalanced expression of c-Myc over wildtype p53. Although p53 repression in cancer cells is frequently associated with the loss of ARF, the results embedded in this thesis disclose an alternate mechanism whereby c-Myc inactivates p53 through the actions of the c-Myc-Inducible Long noncoding RNA Inactivating P53 (MILIP). MILIP functions to promote p53 polyubiquitination and turnover by reducing p53 SUMOylation through suppressing tripartite-motif family-like 2 (TRIML2). MILIP upregulation is observed amongst diverse cancer types and is shown to support cell survival, division and tumourigenicity. Collectively, these results uncover an inhibitory axis targeting p53 through a pan-cancer expressed RNA accomplice that links c-Myc to suppression of p53.

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Tseng, Po-Jung, and 曾柏榕. "(1)Newly Designed Cycloplatinated Polymer Dots as Photocatalysts for Visible Light–driven Hydrogen Evolution(2)Modification Polymer Dots with PEG Moieties to Reduce Non-specific Biomolecular Adsorption." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/rws683.

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碩士 國立中山大學 化學系研究所 106 (1) Newly Designed Cycloplatinated Polymer Dots as Photocatalysts for Visible Light–driven Hydrogen Evolution Overuse of fossil fuels is intensifying air pollution and greenhouse effect. Thus, developing a clean, renewable energy is a matter of utmost urgency. Hydrogen has been identified as a potential energy carrier because of its high energy capacity and environmental friendliness. However, hydrogen does not exist naturally on earth; we have to make it before use it. Nowadays, there are two main pathways to produce hydrogen that is steam methane reforming and water electrolysis. Among these pathways, water electrolysis is considered as a sustainable way to produce hydrogen because its feedstock is water. However, water splitting is an uphill reaction, requiring the energy supplied from an external resource. If this energy can be obtained from a renewable energy source such as solar energy, hydrogen can then be considered as a green energy totally. In this research, we provide a series of cycloplatinated polymer dots as photocatalyst, in which the platinum complex unit is used as a co-monomer and then linked to a conjugated polymer through Suzuki coupling polymerization. After optimizing the ratio of the Pt complexes, the hydrogen evolution rate (HER) of the cycloplatinated Pdots can be enhanced 9-times higher than the pristine Pdots under the same conditions. Furthermore, the enhancement of the reaction time and the stability are observed by introducing the cycloplatinated Pdots as photocatalysts. Based on the outstanding performance, our newly designed Pdots systems are promised to be a new type of photocatalysts for visible light–driven hydrogen evolution. Keywords: Semiconducting polymers, Polymer dots, Photocatalysts, Visible light, Hydrogen evolution (2) Modification Polymer Dots with PEG Moieties to Reduce Non-specific Biomolecular Adsorption Lately, semiconducting polymer nanoparticles with small sizes (< 30 nm) have been new highly fluorescent probes in optical imaging techniques because of their outstanding fluorescence brightness, good photostability, and minimal toxicity to biosystems. Due to hydrophobic polymer composition, some challenges limit Pdots development to the clinic like uptake by the reticuloendothelial system (RES), nonspecific binding, and entrapment in the live. The research shows that the addition of poly-ethylene glycol (PEG) into nanoparticles reduces RES uptake and increases circulation time in vivo versus uncoated one. Pdots formation is driven by hydrophobic interactions, means polymers in the Pdots are physically associated with each other. In many cases, the functional molecules may fall off from the nanoparticles due to the weak non-covalent interactions. In this research, a molecular with PEG moieties was first synthesized and then covalently linked to a conjugated polymer through Suzuki coupling. Based on this covalent linking strategy, we hope the PEGylated pdots could load more PEGylated molecular and diminish non-specific effect in biological environment. Keywords: PEGylation、Polymer dots、Non-specific effect、Bioimaging、FRET。

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Maluleke, Mashangu Justice. "Comparative analysis of activity based costing as an alternative to the traditional costing methods in SASSA." Diss., 2019. http://hdl.handle.net/10500/26798.

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Abstracts in English, Xhosa and Afrikaans The South African Social Security Agency (SASSA) is the mechanism that enables service delivery to alleviate poverty in South Africa through the payment of social grants as mandated by the Social Security Agency Act No. 9 of 2004. The rapid increase of social grant beneficiaries in the past decade, fuelled by social inequality, directly affects the administration cost associated with social grants. This study aimed to investigate the allocation of indirect costs related to the administrative elements that makes it possible for SASSA to pay social grants. Semi-structured interviews were conducted; the study concluded that ABC (activity-based costing) could be implemented as an alternative to the traditional costing (TC) method on a pilot project basis. The study also recommended a framework for SASSA to consider in laying the foundation to start the process of ABC implementation. Drawing from the research conducted, further studies on the implementation of ABC principles within the public sector could be pursued. Ejensi ya Vuhlayiseki bya Vanhu ya Afrika Dzonga ku nga South African Social Security Agency (SASSA) i ndlela leyi endlaka leswaku mphakelo wa vukorhokeri wu koteka ku hunguta vusweti eAfrika Dzonga hikwalaho ka ku hakeriwa ka timalimpfuneto ta vanhu (social grants) tanihileswi swi pfumeleriweke hi Nawu wa Social Security Agency Act 9 wa 2004. Ku ndlandlamuka ka vavuyeriwa va malimpfuneto ya vanhu swi khumbha hi ku kongomisa tihakelo ta vulawuri leti fambelanaka na timalimpfuneto ta vanhu. Dyondzo leyi yi kongomisiwile eka ku lavisisa mphakelo wa tihakelo to ka ti nga kongomisi leti fambelanaka na swiyenge swa vulawuri leswi endlaka leswaku SASSA yi kota ku hakela timalimpfuneto ta vanhu. Ku endliwe ti-semi-structured interview. Dyondzo yi kumile leswo ti-activity-based costing (ABC) ti nga tirhisiwa hi ndlela yo cincana na maendlelo ya vupimahakelo bya ntolovelo eka projeke ya nkarhinyana. Dyondzo yi bumabumerile leswaku ku anakanyiwa rimba ro nyika mianakanyo yo sungula maendlelo yo tirhisa ABC. Die “South African Social Security Agency” (SASSA) verlig armoede in Suid-Afrika deur ingevolge die “Social Security Agency Act” 9 van 2004 sosiale toelaes te betaal. Die aansienlike toename in die aantal begunstigdes het ŉ uitwerking op die administrasiekoste van sosiale toelaes. Hierdie studie ondersoek die toewysing van indirekte koste ten opsigte van die administratiewe elemente wat SASSA in staat stel om sosiale toelaes te betaal. Halfgestruktureerde onderhoude is gevoer. In hierdie studie word tot die gevolgtrekking gekom dat aktiwiteitsgebaseerde kosteberekening (ABK) as ŉ alternatief vir en as ŉ proefprojek die tradisionele kosteberamingsmetode geïmplementeer kan word. ŉ Raamwerk word aanbeveel wat as ŉ grondslag kan dien vir die implementering van ABK. College of Accounting Sciences M. Phil. (Accounting Sciences)

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SBRANA, ALESSANDRO. "Faculty Development Centri di Professionalità Accademica (CPA)." Doctoral thesis, 2018. http://hdl.handle.net/11393/251175.

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mondo universitario ha subito un’ondata di cambiamenti che si possono ricondurre alla ricerca dell’eccellenza, declinata secondo le due dimensioni della valutazione e della rendicontazione. Tre sono quelli più evidenti: il primo, il passaggio da una ricerca curiosity driven a una ricerca funzionale al raggiungimento di risultati valutabili in tempi brevi; dalla ricerca pura a quella applicata, da un approccio problem-making a uno problem-solving, da una conoscenza come processo a una conoscenza come prodotto, da un modello disinteressato a uno utilitaristico (Barnett, 1994); il secondo, riguardante l’offerta formativa: dal momento che si è modificato il modo di concepire l’apprendimento; i curricula tendono a essere definiti in termini di risultati di apprendimento predefiniti (Blackmore, 2016); il terzo, peculiare della struttura amministrativa: dal momento in cui sono divenute essenziali una serie di nuove sovrastrutture (programmazione, valutazione, controlli, comunicazione) rispetto al mandato originario della struttura universitaria si registra un aumento consistente del personale delle strutture amministrative. Questi cambiamenti devono fare i conti con la perdita di prestigio della vita accademica, il cambiamento del ruolo dello studente, che è diventato sempre più importante e l’aumento delle procedure burocratiche che rischiano di ingessare un sistema un tempo caratterizzato da un’elevata autonomia. Per consentire alle strutture universitarie di affrontare le sfide culturali a partire dagli anni Settanta nelle università nord-americane si sono strutturate iniziative finalizzate allo sviluppo e alla promozione di una migliore offerta formativa. Tali iniziative vengono definite con l’espressione Faculty Development (FD), una policy accademica finalizzata a creare le condizioni per un miglioramento delle competenze di tutti coloro che sono coinvolti nelle attività svolte in un ateneo. Nella realtà italiana emerge la mancanza di una vera politica di formazione al teaching per i ricercatori e i docenti universitari, per non parlare dell’esigenza di superare il pregiudizio, di gentiliana memoria, secondo il quale non è necessario apprendere a insegnare, ma sia sufficiente avere successo nella ricerca, cui si aggiunge nell’ultimo decennio una continua e affannata richiesta al personale accademico di azioni organizzative, valutative e documentali, che assorbono tempo e energie senza il supporto di adeguati apparati gestionali e senza predisporre indagini valutative capaci di misurare l’effettivo esito di tutte queste azioni. L’effetto finale è un evidente declino (Capano et al., 2017) dell’istituzione universitaria. Si può ipotizzare che la cultura del organizzazione propria del Faculty Development possa contribuire nel contesto italiano a fornire azioni a supporto del cambiamento: è quanto mai essenziale dotare gli atenei di risorse funzionali a riqualificare la vita accademica, fornendo al personale accademico gli strumenti necessari per performare una buona scholarship, realizzare un’efficace offerta formativa e attuare adeguate forme di terza missione, capaci di incrementare la vita culturale della comunità. Il presente studio si propone come un’analisi sistematica della letteratura sul tema del Faculty Development, che persegue l’obiettivo di sviluppare una disamina estesa dell’oggetto, in modo che l’esplicitazione della datità raccolta fornisca un’analisi del fenomeno che possa essere di supporto a un’avveduta educational policy nel campo della formazione universitaria. Nel contesto italiano ad oggi non esiste una cultura di attenzione ai contesti di apprendimento universitario. L’offerta formativa è concepita come offerta di pacchetti curriculari e la predisposizione delle condizioni di apprendimento per il conseguimento del titolo universitario si risolve nella organizzazione di una serie di lezioni, frontali o laboratoriali, senza che tutto questo sia innervato da una specifica intenzionalità didattica. Questa immagine poco confortante non intende affatto trascurare tutti i casi di buone prassi sviluppati nei vari corsi di studio, ma il buono che emerge è demandato all’impegno del singolo, senza che l’istituzione universitaria si interroghi sul come predisporre le condizioni per il potenziamento della qualità dei processi di apprendimento. A fronte di questa situazione la necessità di migliorare la qualità dell’insegnamento non è mai stata così stringente e sfidante come lo è oggi, in un clima di continuo cambiamento della formazione superiore. Nuove tendenze definiscono la formazione superiore, attraversando confini istituzionali e nazionali. Essi influiscono sul modo in cui un insegnamento efficace viene concettualizzato, condotto e supportato, valutato, valorizzato e riconosciuto. È necessario affrontare temi quali l’inadeguata preparazione per il lavoro accademico nei corsi di studio magistrali, l’incapacità dei docenti a trasferire competenze, la crescente complessità degli ambienti accademici, le attese e le responsabilità istituzionali, la necessità di preparare meglio gli studenti con bisogni diversi, e la necessità di stare al passo con i balzi della conoscenza e i cambiamenti nelle professioni. Migliorare la qualità della didattica è inoltre essenziale perché consente di ridurre il numero degli abbandoni. È venuto il momento di transitare da un’offerta formativa di tipo episodico a una prospettiva di esperienze di apprendimento in continuità nel tempo, per accompagnare la formazione dei docenti in un modo strutturalmente organizzato (Webster-Wright, 2009). Sulla base della rilevazione fenomenica, sono emerse le seguenti domande di ricerca: che cosa è il FD? Cosa consente di fare? Come si mette in pratica? Quali sono le potenzialità? Quali sono i limiti? Il FD ha il compito di incentivare i docenti ad interessarsi ai processi di insegnamento e apprendimento e a procurare un ambiente sicuro e positivo nel quale fare ricerca, sperimentare, valutare e adottare nuovi metodi (Lancaster et al. 2014). È finalizzato a promuovere cambiamento sia a livello individuale sia a livello organizzativo. Occupa un posto centrale il miglioramento delle competenze di teaching (Steinert, 2014). Due importanti obiettivi sono rappresentati dalla promozione delle capacità di leadership e di gestione dei contesti (Steiner et al., 2012). Una volta definite le metodologie del teaching, che possono essere oggetto di apprendimento da parte del personale accademico, è risultato necessario identificare le principali modalità formative che un centro di Faculty Development (FDc) dovrebbe mettere in atto per favorire l’apprendimento delle competenze didattiche. Per comprenderne la funzione reale è stato utile prendere in esame le attività proposte dai più importanti centri del panorama accademico nordamericano, analizzandone la struttura organizzativa, le risorse disponibili ed identificandone le due figure principali: il responsabile dell’organizzazione dei processi formativi e il responsabile della struttura. L’analisi dei casi ha consentito di evidenziare i molteplici servizi che possono essere forniti da un FDc. Questa analisi di realtà è risultata molto utile poiché ha offerto indicazioni pragmatiche ai fini di una politica accademica innovativa anche in ambito italiano. Alla luce degli argomenti sviluppati è stato possibile ipotizzare anche per gli atenei italiani l’istituzione di “Centri per la professionalità accademica”, indicando possibili iniziative da essi realizzabili, che potrebbero trovare spazio nella realtà del nostro paese.

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Dissertations / Theses on the topic 'Pen drive'

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