Thèses sur le sujet « Analisi dimensionale »
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1
Pappalardo, Maria. « Misure sperimentali e analisi statistica per la valutazione dell'accuratezza dimensionale di campioni realizzati mediante fabbricazione additiva ». Master's thesis, Alma Mater Studiorum - Università di Bologna, 2019.
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Il presente studio ha posto le basi per la generazione di modelli di correlazione tra parametri di processo e parametri di qualità del prodotto per la tecnologia Multi Jet Fusion. Poiché l'accuratezza dimensionale è ad oggi il principale limite all'applicazione industriale di questa tecnologia, si è deciso di effettuare delle osservazioni e delle misure sperimentali su apposite geometrie benchmark di piccole e medio-grandi dimensioni rispetto allo spazio di costruzione offerto dal sistema HP Jet Fusion 3D 4200. La pianificazione di tali esperimenti è avvenuta con l'obiettivo di generare un modello di correlazione tra l'accuratezza dimensionale e alcuni parametri di processo, quali: dimensione nominale, irradianza ed orientamento.
Nello specifico, il lavoro è stato suddiviso come segue. Nel primo capitolo sono state illustrate alcune caratteristiche generali dei processi additivi, per poi passare a descrivere in maniera più dettagliata la tecnologia Multi Jet Fusion. Tale processo è stato analizzato nel capitolo successivo in tutte le sue fasi, dalla progettazione ad hoc dei componenti fino alla fase di post-produzione, ponendo particolare attenzione ai parametri di processo che influenzano la qualità dei componenti stampati. Il terzo capitolo è stato dedicato all’analisi della progettazione degli esperimenti, durante la quale si è messo in evidenza i parametri di processo inclusi e quelli trascurati. Sempre in questo capitolo, sono stati descritti i metodi di misurazione utilizzati, ovvero un calibro digitale e una bilancia di precisione digitale. Infine, nell'ultimo capitolo sono stati descritti e commentati i risultati delle misure effettuate e della loro elaborazione, che è avvenuta per mezzo di tecniche statistiche quali: analisi dei residui, analisi della varianza e analisi di regressione polinomiale.
2
Vaziri, Amir Salar. « Modello zero dimensionale di un motore a combustioni interna ». Master's thesis, Alma Mater Studiorum - Università di Bologna, 2019.
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La modellazione zero-dimensionale del motore ad accensione comandata ha conosciuto un rapido sviluppo nelle ultime decadi, ed è stata sviluppata principalmente con lo scopo di potere utilizzare i moderni metodi di calcolo numerico per l'ottimizzazione del motore a combustione interna.
Il presente elaborato è basato sulla traduzione da Matlab a Python-3 del programma GuiEngine0D, oggetto di un precedente lavoro, basato sull'analisi zero-dimensionale di un motore ad iniezione diretta.
Il primo capitolo riporta le generalità sui cicli motore con un approfondimento sul ciclo Miller, vista la possibilità di variare l'angolo IVC fra i dati iniziali del codice così da permettere un'alternativa al ciclo Otto.
Nel secondo capitolo si riportano i modelli, con le relative ipotesi semplificative, usati nel codice per il calcolo dei parametri di interesse motoristico.
Infine nel terzo capitolo vengono mostrate delle simulazioni fatte tramite l'utilizzo del codice, riportandone i risultati e le relative considerazioni.
3
BADALAMENTI, Maria Antonietta. « RILIEVO E ANALISI GEOMETRICA, DIMENSIONALE E COSTRUTTIVA DELLE VOLTE A MUQARNAS COSTRUITE A PALERMO NEL XII SECOLO ». Doctoral thesis, Università degli Studi di Palermo, 2020. http://hdl.handle.net/10447/394889.
Texte intégralRésumé :
Questa ricerca affronta lo studio delle caratteristiche geometriche e costruttive delle volte a muqarnas costruite a Palermo nel XII secolo, al fine di contribuire al dibattito ancora aperto sulle origini di questi apparati decorativi e la loro trasmissione. Gli assunti da cui la ricerca prende le mosse sono principalmente due: il Rilievo e il Disegno sono strumenti privilegiati per indagare, conoscere e comprendere l’architettura; la Sicilia nel XII secolo è un luogo di sperimentazione e non di sola ricezione di codici provenienti dall’Egitto. Lo studio proposto si prefigge pertanto due obiettivi: costituire, tramite il rilievo con laser scanner, un archivio digitale tridimensionale dei muqarnas di Palermo; dimostrare l’ipotesi che i progetti dei muqarnas di Palermo siano stati concepiti assumendo come riferimento un unico schema geometrico e metrico.This research focuses on the geometric and constructive characteristics of the muqarnas vaults, built in Palermo in the XII century, to contribute to the discussion, still open, on the muqarnas origin and transmission. The research takes into account that: survey and drawing are effective tools to investigate, explore and understand architecture; during the XII century Sicily was a place of experimentation, not just receiving codes from the Egypt. This research aims at a twofold purpose: to set up a 3D digital ‘repository’ of the muqarnas vaults of Palermo, through a comprehensive laser scanning survey; to investigate on muqarnas vaults of Palermo design and prove that they were built using a specific metric and geometric pattern.
4
Baiocchi, Lorenzo. « Ottimizzazione dimensionale di manufatti espansi superleggeri a matrice poliolefinica reticolata : studio del processo di stampaggio ad iniezione e primi passi verso lo sviluppo software ». Master's thesis, Alma Mater Studiorum - Università di Bologna, 2018. http://amslaurea.unibo.it/16740/.
Texte intégralRésumé :
Il presente lavoro di tesi dà il via ad un progetto di ricerca il cui scopo ultimo è lo sviluppo di un software di modellazione Computer Aided Engineering (CAE) in grado di prevedere l’espansione che avviene durante la fase di esplosione di un manufatto formato tramite stampaggio ad iniezione, a partire da materiali polimerici a matrice poliolefinica espansibile e reticolabile. Una stima accurata ed a priori dell’espansione nelle tre dimensioni tramite un software del genere, comporterebbe un tangibile e consistente risparmio economico e temporale durante il processo di progettazione di stampi utilizzati per la produzione industriale in serie di prodotti termoindurenti superleggeri con microstruttura cellulare a celle chiuse. Una prima fase del lavoro sperimentale è stata orientata verso la ricerca di correlazioni matematiche tra i coefficienti di espansione nelle varie dimensioni di provini standardizzati. Le correlazioni sono state determinate con successo ed è stata anche testata la loro stabilità rispetto ad una variazione della formulazione del materiale stampato. La seconda e ultima fase del lavoro sperimentale ha invece testato l’influenza di una modifica dei parametri di stampaggio sulle correlazioni precedentemente determinate. Infine, è stata proposta una prima ipotesi di un modello concettuale del processo, consistente con i risultati ottenuti.
5
Cassanelli, Camilla. « Insieme di Kakeya ». Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2020. http://amslaurea.unibo.it/20690/.
Texte intégralRésumé :
In questo elaborato di tesi viene trattato il Problema di Kakeya. Nel primo capitolo si considera il caso bidimensionale e si costruisce l'insieme di Besicovitch, anche detto insieme di Kakeya, calcolandone l'area. Nella prima parte del secondo capitolo viene sviluppato il problema utilizzando la dualità, mentre nella seconda si risolve il problema considerando la costruzione di insiemi piani di misura nulla contenenti cerchi di ogni raggio. Successivamente si sviluppa il problema in dimensione maggiore, generalizzandolo al caso n-dimensionale.
Nell'ultimo capitolo si mostra la relazione del problema di Kakeya con l'analisi armonica.
6
Rocca, Rossella. « Studio dei parametri che determinano la gittata sistolica e la pressione aortica ». Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2013. http://amslaurea.unibo.it/6090/.
Texte intégralRésumé :
La stesura di questo elaborato di tesi trova le basi sull’articolo di Stergiopulos et al. “Determinants of stroke volume and systolic and diastolic aortic pressure” pubblicato sulla rivista americana American Journal of Physiology-Heart and Circulatory Physiology nel 1996.
Si cerca di investigare sull’importanza che ricoprono alcuni parametri che descrivono il muscolo cardiaco e l’albero arterioso e sulla loro rispettiva influenza sulla pressione sistolica, pressione diastolica e sul volume di sangue eiettato in un battito, ovvero la gittata sistolica.
Si procede con la descrizione in dettaglio della funzionalità cardiaca mediante il modello ad elastanza tempo variabile e il modello windkessel a tre elementi simulando così la contrazione ventricolare e l’albero arterioso sistemico.
In dettaglio per quanto riguarda la struttura dell’elaborato è bene specificare che l’analisi teorica affrontata nei primi due capitoli ha l’obiettivo primario di:
1) chiarire i principali e caratteristici meccanismi che si trovano alla base della funzionalità cardiaca e procedere quindi con i richiami relativi alla fisiologia del sistema cardio-circolatorio facendo particolare attenzione al concetto di ciclo cardiaco, ciclo pressione-volume e fattori che determinano la funzionalità cardiaca in dettaglio;
2)illustrare quelli che sono i principali modelli di riferimento presenti in letteratura che descrivono la contrazione del ventricolo sinistro in termini di analisi pressione-volume ventricolari istantanei.
Dal terzo capitolo in avanti si prosegue verso quello che è il vivo della trattazione dell’articolo di riferimento, nel capitolo appena citato si fa luce sui dettagli che caratterizzano il modello matematico utilizzato per approssimare al meglio il sistema cuore-sistema arterioso e sull’applicazione della teoria dell’analisi dimensionale mediante l’utilizzo del Teorema di Buckingham al fine di ricavare i parametri di interesse.
Nel quarto capitolo si riportano i risultati dello studio con annessa validazione del modello e la sua applicazione rispetto al caso umano.
Il quinto capitolo è sede della discussione dei risultati ottenuti cercando di far luce sull’universalità e applicabilità delle formule empiriche ottenute e su eventuali limitazioni e implicazioni riscontrabili.
Tale elaborato si chiude con alcune conclusioni in merito allo studio effettuato.
7
Lando, Giovanni. « Studio di soluzioni di movimentazione per un propulsore navale azimutale ». Master's thesis, Alma Mater Studiorum - Università di Bologna, 2018. http://amslaurea.unibo.it/16472/.
Texte intégralRésumé :
Il presente elaborato di tesi magistrale raccoglie i risultati dello studio, svolto presso l’azienda Calzoni S.r.l. di Calderara di Reno, di un meccanismo di movimentazione per un propulsore azimutale navale. Il propulsore è studiato per equipaggiare un moderno sottomarino militare e rappresenta una soluzione di propulsione ausiliaria per le operazioni di manovra e posizionamento di precisione del veicolo marino.
L’obiettivo principale del lavoro consiste nella sintesi e nel dimensionamento di un meccanismo che permetta la movimentazione del propulsore e, allo stesso tempo, sia in grado di resistere alle sollecitazioni derivanti da un’esplosione sottomarina non a contatto senza che ne venga pregiudicata la funzionalità.
La definizione della soluzione propulsiva è articolata nelle seguenti fasi:
- Un iniziale studio preliminare dell’elica marina per individuare una soluzione ottimizzata dei parametri caratteristici del propulsore e specificare la configurazione propulsiva che meglio si adatta a generare elevati valori di spinta a basse velocità.
- L’individuazione dell’architettura del meccanismo che permetta la movimentazione del propulsore e la conseguente sintesi dimensionale per determinarne dimensioni e posizioni limite durante le fasi della movimentazione.
- Un’analisi cinetostatica del meccanismo per analizzarne il movimento e definire il carico funzionale utile per dimensionare opportunamente gli organi di attuazione.
- L’individuazione dello spettro di risposta agli urti (Shock Response Spectrum) per caratterizzare la risposta del sistema ad uno shock impulsivo.
- Il dimensionamento dei principali organi del meccanismo di movimentazione ipotizzando un carico statico equivalente ad un’esplosione sottomarina non a contatto.
- Considerazioni finali.
8
Oliveira, Fernanda Moura de. « Analise harmonica na esfera unitaria d-dimensional real ». [s.n.], 2005. http://repositorio.unicamp.br/jspui/handle/REPOSIP/306564.
Texte intégralRésumé :
Orientadores: Sergio Antonio Tozoni, Alexander KushpelDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Matematica, Estatistica e Computação Cientifica
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Resumo: O objetivo da dissertação e desenvolver um texto em português sobre Análise Harmônica na esfera d-dimensional real e aplicar os resultados deste texto no estudo de um teorema de multiplicadores. Nos dois primeiros capítulos e realizado um estudo sobre funções harmônicas em um domínio do espaço euclidiano Rd+1, harmônicos esféricos, representações de SO(d+1), harmônicos zonais, polinômios ultraesféricos e sobre o operador de Laplace Beltrami para a esfera. Finalmente, no terceiro capítulo é estudado um teorema de multiplicadores recente, o qual fornece condições suficientes para que um operador multiplicador seja limitado de Lp(Sd) em Lq(Sd), para quaisquer p e q, 1=p, q=8. Como aplicação deste teorema são obtidas estimativas superiores para n-larguras de Kolmogorov de classes de Sobolev nos espaços Lq(Sd), 1=p, q= 8, g > 0
Abstract: The purpose of this work is to develop a text in Portuguese about Harmonic Analysis on the d-dimensional real sphere Sd and to apply the results of the text to study a multiplier theorem. In the first two chapters it is made a study about harmonic functions in a domain of the euclidian space Rd+1, spherics harmonics, representations of SO(d+1), zonal harmonics, ultraspherics polynomials and about the Laplace Beltrami operator on the sphere. Finally, in the third chapter it is studied a recent multiplier theorem which gives sufficient conditions for a multiplier operator be bounded from Lp(Sd) to Lq(Sd), for 1=p, q=8. As application of this theorem are obtained upper bounds for n-widths of Kolmogorov type of Sobolev classes in the spaces Lq(Sd), 1=p, q= 8, g > 0
Mestrado
Matematica
Mestre em Matemática
9
Silva, Rui Rodrigo Cabral e. « Analise numerica dimensional aplicada a combustão in-situ (CIS) ». [s.n.], 2010. http://repositorio.unicamp.br/jspui/handle/REPOSIP/264249.
Texte intégralRésumé :
Orientador: Osvair Vidal TrevisanDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica, Instituto de Geociencias
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Resumo: Este trabalho apresenta uma metodologia de trabalho aplicável ao desenvolvimento de projetos de CIS utilizando dados de ensaios laboratoriais, simulação numérica e análise dimensional. A CIS envolve uma variedade de fenômenos que ocorrem simultaneamente, como a transferência de massa, calor, reações químicas entre outros. A utilização dos resultados obtidos em ensaios laboratoriais está muito sujeita à erros de escala e com a metodologia desenvolvida neste trabalho espera-se contornar este problema. Primeiramente é apresentado nosso modelo físico utilizado neste trabalho, que é o tubo de combustão desenvolvido na Unicamp. Através da análise dimensional, desenvolvem-se três modelos de simulação sobre nosso modelo físico em escalas diferente, sendo que o modelo menor possui as dimensões do tubo de combustão, o modelo maior possui as dimensões de um campo de petróleo e o modelo intermediário possui suas dimensões dez vezes maiores que o modelo menor e cinco vezes menores que o modelo de campo. Foram utilizados dados sintéticos da composição de óleo e propriedades permoporosas. Os resultados obtidos foram coerentes e mostram que existem correlações entre as variações geométricas dos modelos e os fenômenos de transferência de massa, transferência de energia e reações químicas. Sendo assim, com uma boa análise dimensional é possível criar um comportamento equivalente em todos os modelos dos fenômenos citados
Abstract: This paper presents a methodology of work applicable to the development of ISC projects using data from laboratory tests, numerical simulation and dimensional analysis. The ISC includes a variety of phenomena that occur simultaneously, such as mass transfer, heat transfer, chemical reactions among others. The use of data from laboratory tests is very subject to scale errors, which are minored with the methodology developed in the present work. First is presented our physical model used in this work, which is the combustion tube developed at Unicamp. By dimensional analysis, were developed three simulation models based on our physical model on different scales, the smaller model has the characteristics of the combustion tube, the bigger model has the dimensions of an oilfield, and the intermediate model has dimensions ten times greater than the combustion tube and five times smaller than the field model. We used synthetic data for oil composition, permeability and porosity. The results were consistent and show that there are correlations between the variations of geometric models and the phenomena of mass transfer, energy transfer and chemical reactions. Thus with a good dimensional analysis it's possible create an equivalent behavior of these effects in all models
Mestrado
Reservatórios e Gestão
Mestre em Ciências e Engenharia de Petróleo
10
Mautone, Massimiliano <1988>. « Analisi del music business : le etichette di piccola media dimensione ». Master's Degree Thesis, Università Ca' Foscari Venezia, 2014. http://hdl.handle.net/10579/5116.
Texte intégralRésumé :
L'analisi di ricerca è focalizzata sulle imprese di piccola-media dimensione produttrici di musica. La ricerca vuole concentrarsi in particolare sui rapporti che intercorrono tra queste imprese e gli artisti, dal punto di vista gestionale, contrattuale e normativo.
11
Bianco, Carlo <1980>. « Analisi d'immagine, patologia quantitativa e dimensione frattale in patologia veterinaria : Densita' e forme ». Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amsdottorato.unibo.it/6833/1/ANALISI_D%E2%80%99IMMAGINE%2C_PATOLOGIA_QUANTITATIVA_E.pdf.
Texte intégralRésumé :
Fino dagli albori della metodica scientifica, l’osservazione e la vista hanno giocato un ruolo fondamentale. La patologia è una scienza visiva, dove le forme, i colori, le interfacce e le architetture di organi, tessuti, cellule e componenti cellulari guidano l’occhio del patologo e ne indirizzano la scelta diagnostico-classificativa. L’osservazione del preparato istologico in microscopia ottica si attua mediante l’esame e la caratterizzazione di anomalie ad ingrandimenti progressivamente crescenti, a diverse scale spaziali, che partono dalla valutazione dell’assetto architettonico sovracellulare, per poi spostarsi ad investigare e descrivere le cellule e le peculiarità citomorfologiche delle stesse. A differenza di altri esami di laboratorio che sono pienamente quantificabili, l’analisi istologica è intrinsecamente soggettiva, e quindi incline ad un alto grado di variabilità nei risultati prodotti da differenti patologi. L’analisi d’immagine, l’estrazione da un’immagine digitale di contenuti utili, rappresenta una metodica oggettiva, valida e robusta ormai largamente impiegata a completamento del lavoro del patologo. Si sottolinea come l’analisi d’immagine possa essere vista come fase descrittiva quantitativa di preparati macroscopici e microscopici che poi viene seguita da una interpretazione. Nuovamente si sottolinea come questi descrittori siano oggettivi, ripetibili e riproducibili, e non soggetti a bassa concordanza inter operatore. La presente tesi si snoda attraverso un percorso concettuale orientato ad applicazioni di analisi d’immagine e patologia quantitativa che parte dalle applicazioni più elementari (densità, misure lineari), per arrivare a nozioni più avanzate, quali lo studio di complessità delle forme mediante l’analisi frattale e la quantificazione del pattern spaziale di strutture sovracellulari.Until the dawn of the scientific method, observation was pivotal. Pathology is a visual science, where the forms, colors, interfaces and architectures of organs, tissues, cells and cell components direct the diagnosis. The observation of the histological preparation in optical microscopy is implemented through the examination and characterization of anomalies at progressively higher magnifications, at different spatial scales, which start from the evaluation of sovracellular architecture, then move to investigate and describe the cells and cytological fetures. In contrast to other laboratory tests that are quantitative, histological analysis is inherently subjective, and therefore prone to a high degree of variability in the results produced by different pathologists. The image analysis, extraction from a digital image of meaningful content, is an objective and robust method, now widely used to aid the pathologist. Should be stressed that image analysis can be seen as a quantitative descriptor of macroscopic and microscopic specimens, followed by an interpretation (the diagnosis). This thesis unfolds through different applications of image analysis and quantitative pathology that starts with the most basic applications (density, linear measurements), to get to more advanced concepts, such as the study of the complexity of shapes by the ' fractal analysis and quantification of the spatial patterns of sovracellular structures.
12
Bianco, Carlo <1980>. « Analisi d'immagine, patologia quantitativa e dimensione frattale in patologia veterinaria : Densita' e forme ». Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amsdottorato.unibo.it/6833/.
Texte intégralRésumé :
Fino dagli albori della metodica scientifica, l’osservazione e la vista hanno giocato un ruolo fondamentale. La patologia è una scienza visiva, dove le forme, i colori, le interfacce e le architetture di organi, tessuti, cellule e componenti cellulari guidano l’occhio del patologo e ne indirizzano la scelta diagnostico-classificativa. L’osservazione del preparato istologico in microscopia ottica si attua mediante l’esame e la caratterizzazione di anomalie ad ingrandimenti progressivamente crescenti, a diverse scale spaziali, che partono dalla valutazione dell’assetto architettonico sovracellulare, per poi spostarsi ad investigare e descrivere le cellule e le peculiarità citomorfologiche delle stesse. A differenza di altri esami di laboratorio che sono pienamente quantificabili, l’analisi istologica è intrinsecamente soggettiva, e quindi incline ad un alto grado di variabilità nei risultati prodotti da differenti patologi. L’analisi d’immagine, l’estrazione da un’immagine digitale di contenuti utili, rappresenta una metodica oggettiva, valida e robusta ormai largamente impiegata a completamento del lavoro del patologo. Si sottolinea come l’analisi d’immagine possa essere vista come fase descrittiva quantitativa di preparati macroscopici e microscopici che poi viene seguita da una interpretazione. Nuovamente si sottolinea come questi descrittori siano oggettivi, ripetibili e riproducibili, e non soggetti a bassa concordanza inter operatore. La presente tesi si snoda attraverso un percorso concettuale orientato ad applicazioni di analisi d’immagine e patologia quantitativa che parte dalle applicazioni più elementari (densità, misure lineari), per arrivare a nozioni più avanzate, quali lo studio di complessità delle forme mediante l’analisi frattale e la quantificazione del pattern spaziale di strutture sovracellulari.Until the dawn of the scientific method, observation was pivotal. Pathology is a visual science, where the forms, colors, interfaces and architectures of organs, tissues, cells and cell components direct the diagnosis. The observation of the histological preparation in optical microscopy is implemented through the examination and characterization of anomalies at progressively higher magnifications, at different spatial scales, which start from the evaluation of sovracellular architecture, then move to investigate and describe the cells and cytological fetures. In contrast to other laboratory tests that are quantitative, histological analysis is inherently subjective, and therefore prone to a high degree of variability in the results produced by different pathologists. The image analysis, extraction from a digital image of meaningful content, is an objective and robust method, now widely used to aid the pathologist. Should be stressed that image analysis can be seen as a quantitative descriptor of macroscopic and microscopic specimens, followed by an interpretation (the diagnosis). This thesis unfolds through different applications of image analysis and quantitative pathology that starts with the most basic applications (density, linear measurements), to get to more advanced concepts, such as the study of the complexity of shapes by the ' fractal analysis and quantification of the spatial patterns of sovracellular structures.
13
Albiero, Daniel. « Avaliação do preparo de solo empregando o sistema de cultivo conservacionista em faixas com 'paraplow¿ rotativo usando a analise dimensional ». [s.n.], 2006. http://repositorio.unicamp.br/jspui/handle/REPOSIP/257151.
Texte intégralRésumé :
Orientador: Antonio Jose da Silva MacielDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agricola
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Resumo: Este trabalho foi desenvolvido no campo experimental da Faculdade de Engenharia Agrícola da UNICAMP e teve como objetivo avaliar o novo sistema de preparo de solo Conservacionista em Faixas com "Paraplow" Rotativo, dando ênfase para a aplicação em sistemas de plantio voltados para agricultura familiar. A avaliação foi dividida em três grupos: caracterização da ferramenta como conservacionista; caracterização geométrica da faixa bem preparada; e determinação da configuração operacional ótima para a agricultura familiar. Foi utilizada a técnica de análise dimensional que através do planejamento experimental à ela atrelado define o elenco dos principais parâmetros a serem medidos e importantes para as respectivas determinações, caracterizações e comprovações. Com estes parâmetros definidos, em um total de vinte e dois parâmetros foram realizados o experimento em campo em um delineamento experimental totalmente aleatório, onde foi realizado o experimento com oito tratamentos, onde cada tratamento disposto em uma linha experimental com cinco pontos de coletas de dados antes, e cinco pontos de coleta de dados após a passagem da ferramenta. Para este arranjamento foram feitas duas repetições para cada parâmetro totalizando dezesseis linhas experimentais, perfazendo um total de dez pontos avaliados para cada tratamento. Com os dados coletados foi possível realizar as análises através da: estatística descritiva básica, análise dimensional e análise de variância. Os resultados obtidos demonstram claramente que o "Paraplow" Rotativo é uma ferramenta de preparo de solo conservacionista. As avaliações operacionais indicam que esta ferramenta acoplada a um motocultor de 12 cv é adequada a utilização pela agricultura familiar, tendo capacidades de campo compatíveis com as necessidades das pequenas propriedades. Comparações entre as metodologias da Análise Dimensional e a Análise de Variância de uma via simples, demonstram a superioridade da Análise Dimensional em estudos de dinâmica do solo e avaliações de máquinas de preparo de solo
Abstract: This work was developed in the experimental field of Agricultural Engineering CoI: of State University of Campinas, and it had as objective to evaluate the new system of tillage in strip conservationist with Rotary "Paraplow", it was given emphasis for application in seeding systems appropriate for small fanns. The evaluation was divide( three groups: characterization of tool as conservationist; geometric characterization of st determination of operation configuration for small fanns. It was used the dimensional analysis method for to define the experimental plannin, having been determined which parameters should be measured. These parameters, in a tota twenty two, they were arrangement in a experimental design completely random, where t were realized the experiment with eight treatments, each treatment was allocated in experimental strip, with five points of obtaining data, before and after the action of the tI for these arrangement were made two repetitions for each parameter, totalizing sixt experimental strips, with ten point of obtaining data for each treatment. With these data it ' possible to realize the analysis through: descriptive statistical; dimensional analysis; . variance analysis. The results demonstrate that the Rotary "Paraplow" is a tool of soil till conservationist. The evaluations show that this tool coupled with tiller with 12 cv appropriated for small fanns, it have been compatible field capacity with the needs of sn fanns. Comparisons between the methodologies of dimensional analysis and the varia: analysis of one way, showed the superiority of the dimensional analysis in studies of ~ dynamics and evaluations of soil tillage machines
Mestrado
Maquinas Agricolas
Mestre em Engenharia Agrícola
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Andrade, Cicero Almeida de. « Analise comparativa da alteração dimensional de materiais de moldagem elastomericos, atraves da tecnica do casquete ». [s.n.], 2000. http://repositorio.unicamp.br/jspui/handle/REPOSIP/289094.
Texte intégralRésumé :
Orientador: Frederico Andrade e SilvaTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba
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Resumo: O presente estudo avaliou comparativamente a alteração dimensional de quatro materiais de moldagem elastoméricos de consistência fluida (uma silicona por adição, duas siliconas por condensação e uma mercaptana) através da técnica do casquete. Um modelo metálico (padrão) foi confeccionado contendo dois dentes com preparos tipo coroa total. Sobre este modelo, com um alívio metálico de 0,3mm, foram obtidos os casquetes através da técnica de Neelon (técnica do pincel). As moldagens foram realizadas através de uma prensa de carga estática onde uma força de 0,4 kgf assentava as moldeiras sobre o modelo metálico. As faces oclusais dos dentes preparados possuíam ranhuras, em forma de cruz. Na extremidade de cada ranhura havia pequenos pontos a partir dos quais iniciava-se a leitura. A leitura linear, em microscópio comparador, era feita inicialmente na face oclusal de cada dente distintamente, em seguida lia-se ligando os pontos entre os dois dentes. Os resultados foram analisados estatisticamente e concluiu-se que: não houve diferenças estatisticamente significantes
Abstract: The present study assessed comparatively the dimensional change of four fluid-consistence elastomeric impression materiais (one addition silicone, two condensation silicones and one mercaptan) using the headcap technique. A metal cast (pattern) was made, enclosing two teeth with metal-crown preparation. On this cast, with a O,3-mm metal relief, were obtained the headcaps using Neelon's technique (brush method). The impressions were carried out with a static-weight press, where a strength of 39.2 N (newton) was pressing the trays over the metal cast. The occlusal surfaces of the prepared teeth had cross-wise grooves. In the extreme of each groove there were small points where the reading started. The linear reading, in a comparing microscope, was initially done at the occlusal surface of each teeth distinctly, so following it was read matching the points between the two teeth. The results were statistically analysed and it followed that there were no statistically significant differences
Doutorado
Protese Dental
Doutor em Odontologia
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Fagotti, Fabian. « Uma analise da transferencia de calor bi-dimensional em tubos de calor de condutancia constante ». reponame:Repositório Institucional da UFSC, 1991. https://repositorio.ufsc.br/xmlui/handle/123456789/157721.
Texte intégralRésumé :
Dissertação (mestrado) - Universidade Federal de Santa Catarina. Centro TecnologicoMade available in DSpace on 2016-01-08T17:25:45Z (GMT). No. of bitstreams: 1 83714.pdf: 2198572 bytes, checksum: a08616614360f0805194436404225ff3 (MD5) Previous issue date: 1991
O propósito deste trabalho é estudar os efeitos da condução de calor bi-dimensional em tubos de calor de condutância constante e as conseqüências da modificação das condições impostas pelo meio exterior sobre o desempenho destes, em regime permanente. Para tanto, uma solução do problema utilizando um método analítico inverso é apresentada. Em decorrência da constatação da preponderância do processo de condução de calor, a equação de Laplace é resolvida simultaneamente no invólucro e na estrutura capilar. Com a imposição das hipóteses simplificativas cabíveis, resolve-se um problema de Neumann conjugado a um problema misto. As equações da temperatura são obtidas com a utilização da segunda identidade de Green. Faz-se uso de funções de Green modificadas para o problema de Neumann, expandidas parcialmente e auto-funções. São apresentados os métodos de construção de tais funções e os resultados para três condições de contorno diferentes, impostas na parede externa do tubo. A boa concordância verificada na comparação dos resultados com dados experimentais obtidos de trabalhos anteriores valida a metodologia adotada. Com base nestes resultados é levada a efeito uma análise da influência dos parâmetros que regulam à transferência de calor em tubos de calor sobre o comportamento térmico. A discrepância observada nas comparações com modelos existentes é explicada em função da relevância dos efeitos da condução de calor bi-dimensional em tubos de calor.
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Muliuolis, Alvydas. « Trimačio pakavimo uždavinio algoritmai ir analizė ». Master's thesis, Lithuanian Academic Libraries Network (LABT), 2010. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2010~D_20100813_111700-76840.
Texte intégralRésumé :
Darbe apžvelgiama trimačio pakavimo problemos tipologija. Nagrinėjama trimečio konteinerių pakavimo problema ir jos sprendimo būdai. Pateikiama šakos ir ribos, bei tabu paieškos algoritmų formulavimas ir jų rezultatų analizė.The paper gives an overview of three-dimensional packing problem typology. There are investigating issue of container packing problem and its solutions. Branch and bound, TSpack algorithms formulation and analysis of their results.
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Kanneganti, Raghuveer. « CLASSIFICATION OF ONE-DIMENSIONAL AND TWO-DIMENSIONAL SIGNALS ». OpenSIUC, 2014. https://opensiuc.lib.siu.edu/dissertations/892.
Texte intégralRésumé :
This dissertation focuses on the classification of one-dimensional and two-dimensional signals. The one-dimensional signal classification problem involves the classification of brain signals for identifying the emotional responses of human subjects under given drug conditions. A strategy is developed to accurately classify ERPs in order to identify human emotions based on brain reactivity to emotional, neutral, and cigarette-related stimuli in smokers. A multichannel spatio-temporal model is employed to overcome the curse of dimensionality that plagues the design of parametric multivariate classifiers for multi-channel ERPs. The strategy is tested on the ERPs of 156 smokers who participated in a smoking cessation program. One half of the subjects were given nicotine patches and the other half were given placebo patches. ERPs were collected from 29 channel in response to the presentation of the pictures with emotional (pleasant and unpleasant), neutral/boring, and cigarette-related content. It is shown that human emotions can be classified accurately and the results also show that smoking cessation causes a drop in the classification accuracies of emotions in the placebo group, but not in the nicotine patch group. Given that individual brain patterns were compared with group average brain patterns, the findings support the view that individuals tend to have similar brain reactions to different types of emotional stimuli. Overall, this new classification approach to identify differential brain responses to different emotional types could lead to new knowledge concerning brain mechanisms associated with emotions common to most or all people. This novel classification technique for identifying emotions in the present study suggests that smoking cessation without nicotine replacement results in poorer differentiation of brain responses to different emotional stimuli. Future, directions in this area would be to use these methods to assess individual differences in responses to emotional stimuli and to different drug treatments. Advantages of this and other brain-based assessment include temporal precision (e.g, 400-800 ms post stimulus), and the elimination of biases related to self-report measures. The two-dimensional signal classification problems include the detection of graphite in testing documents and the detection of fraudulent bubbles in test sheets. A strategy is developed to detect graphite responses in optical mark recognition (OMR) documents using inexpensive visible light scanners. The main challenge in the formulation of the strategy is that the detection should be invariant to the numerous background colors and artwork in typical optical mark recognition documents. A test document is modeled as a superposition of a graphite response image and a background image. The background image in turn is modeled as superposition of screening artwork, lines, and machine text components. A sequence of image processing operations and a pattern recognition algorithm are developed to estimate the graphite response image from a test document by systematically removing the components of the background image. The proposed strategy is tested on a wide range of scanned documents and it is shown that the estimated graphite response images are visually similar to those scanned by very expensive infra-red scanners currently employed for optical mark recognition. The robustness of the detection strategy is also demonstrated by testing a large number of simulated test documents. A procedure is also developed to autonomously determine if cheating has occurred by detecting the presence of aberrant responses in scanned OMR test books. The challenges introduced by the significant imbalance in the numbers of typical and aberrant bubbles were identified. The aberrant bubble detection problem is formulated as an outlier detection problem. A feature based outlier detection procedure in conjunction with a one-class SVM classifier is developed. A multi-criteria rank-of-rank-sum technique is introduced to rank and select a subset of features from a pool of candidate features. Using the data set of 11 individuals, it is shown that a detection accuracy of over 90% is possible. Experiments conducted on three real test books flagged for suspected cheating showed that the proposed strategy has the potential to be deployed in practice.
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Aljarrah, Inad A. « Three Dimensional Face Recognition Using Two Dimensional Principal Component Analysis ». Ohio University / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1142453613.
Texte intégral
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FASSI, ENRICO. « L'Unione Europea e la promozione della democrazia. Elementi di analisi della dimensione internazionale dei processi di democratizzazione ». Doctoral thesis, Università Cattolica del Sacro Cuore, 2008. http://hdl.handle.net/10280/235.
Texte intégralRésumé :
La tesi analizza le politiche di promozione della democrazia messe in atto dall'Unione Europea, al fine di inquadrare queste ultime nell'ambito del dibattito sulla dimensione internazionale dei processi di democratizzazione. L'opera si divide in due parti. La prima parte, teorica, pone le basi per la comprensione dei concetti di democrazia, democratizzazione, e dell'influenza del sistema internazionale sui processi di democratizzazione. La seconda parte, empirica, applica tali nozioni, e la definizione di politiche di promozione della democrazia, al caso specifico. Obiettivo della tesi è quello di mostrare la peculiarità dell'azione dell'UE nell'ambito delle politiche di promozione della democrazia.The thesis analyses EU's democracy promotion policies in order to put these latter in relation to the wider debate on the international dimension of democratization. It is divided into two parts. The first, mainly theoretical draws the foundations for the understanding of the concepts of democracy, democratization, and the international dimension of democratization. The second part, empirical, apply these notions and the definition of democracy promotion policies, to the specific case of the EU. The goal is to show the peculiarity of EU's action in this field.
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FASSI, ENRICO. « L'Unione Europea e la promozione della democrazia. Elementi di analisi della dimensione internazionale dei processi di democratizzazione ». Doctoral thesis, Università Cattolica del Sacro Cuore, 2008. http://hdl.handle.net/10280/235.
Texte intégralRésumé :
La tesi analizza le politiche di promozione della democrazia messe in atto dall'Unione Europea, al fine di inquadrare queste ultime nell'ambito del dibattito sulla dimensione internazionale dei processi di democratizzazione. L'opera si divide in due parti. La prima parte, teorica, pone le basi per la comprensione dei concetti di democrazia, democratizzazione, e dell'influenza del sistema internazionale sui processi di democratizzazione. La seconda parte, empirica, applica tali nozioni, e la definizione di politiche di promozione della democrazia, al caso specifico. Obiettivo della tesi è quello di mostrare la peculiarità dell'azione dell'UE nell'ambito delle politiche di promozione della democrazia.The thesis analyses EU's democracy promotion policies in order to put these latter in relation to the wider debate on the international dimension of democratization. It is divided into two parts. The first, mainly theoretical draws the foundations for the understanding of the concepts of democracy, democratization, and the international dimension of democratization. The second part, empirical, apply these notions and the definition of democracy promotion policies, to the specific case of the EU. The goal is to show the peculiarity of EU's action in this field.
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Razafindramanana, Octavio. « Low-dimensional data analysis and clustering by means of Delaunay triangulation ». Thesis, Tours, 2014. http://www.theses.fr/2014TOUR4033/document.
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Les travaux présentés et discutés dans cette thèse ont pour objectif de proposer plusieurs solutions au problème de l’analyse et du clustering de nuages de points en basse dimension. Ces solutions s’appuyent sur l’analyse de triangulations de Delaunay. Deux types d’approches sont présentés et discutés. Le premier type suit une approche en trois-passes classique: 1) la construction d’un graphe de proximité contenant une information topologique, 2) la construction d’une information statistique à partir de ce graphe et 3) la suppression d’éléments inutiles au regard de cette information statistique. L’impact de différentes measures sur le clustering ainsi que sur la reconnaissance de caractères est discuté. Ces mesures s’appuyent sur l’exploitation du complexe simplicial et non pas uniquement sur celle du graphe. Le second type d’approches est composé d’approches en une passe extrayant des clusters en même temps qu’une triangulation de Delaunay est construiteThis thesis aims at proposing and discussing several solutions to the problem of low-dimensional point cloudanalysis and clustering. These solutions are based on the analysis of the Delaunay triangulation.Two types of approaches are presented and discussed. The first one follows a classical three steps approach:1) the construction of a proximity graph that embeds topological information, 2) the construction of statisticalinformation out of this graph and 3) the removal of pointless elements regarding this information. The impactof different simplicial complex-based measures, i.e. not only based on a graph, is discussed. Evaluation is madeas regards point cloud clustering quality along with handwritten character recognition rates. The second type ofapproaches consists of one-step approaches that derive clustering along with the construction of the triangulation
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Shin, Hyejin. « Infinite dimensional discrimination and classification ». Texas A&M University, 2003. http://hdl.handle.net/1969.1/5832.
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Modern data collection methods are now frequently returning observations that should
be viewed as the result of digitized recording or sampling from stochastic processes rather
than vectors of finite length. In spite of great demands, only a few classification methodologies
for such data have been suggested and supporting theory is quite limited. The focus of
this dissertation is on discrimination and classification in this infinite dimensional setting.
The methodology and theory we develop are based on the abstract canonical correlation
concept of Eubank and Hsing (2005), and motivated by the fact that Fisher's discriminant
analysis method is intimately tied to canonical correlation analysis. Specifically, we have
developed a theoretical framework for discrimination and classification of sample paths
from stochastic processes through use of the Loeve-Parzen isomorphism that connects a
second order process to the reproducing kernel Hilbert space generated by its covariance
kernel. This approach provides a seamless transition between the finite and infinite dimensional
settings and lends itself well to computation via smoothing and regularization. In
addition, we have developed a new computational procedure and illustrated it with simulated
data and Canadian weather data.
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Li, Junjie. « Some algorithmic studies in high-dimensional categorical data clustering and selection number of clusters ». HKBU Institutional Repository, 2008. http://repository.hkbu.edu.hk/etd_ra/1011.
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Ayub, Gamel Said Eduardo. « Recobrimento de comprimidos em leito de jorro bi-dimensional : analise do crescimento e transferencia de calor gas-particula ». [s.n.], 1993. http://repositorio.unicamp.br/jspui/handle/REPOSIP/266505.
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Orientador: Sandra Cristina dos Santos RochaDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica
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Resumo: Neste trabalho objetivou-se o estudo da transferência de calor fluido-partícula, da taxa de crescimento da partícula, kl, e eficiência do processo, ?, no recobrimento de comprimidos em um leito de jorro bi-dimensional. As partículas utilizadas foram placebos no formato lenticular, de comprimidos reais, com dp = 7,2117 X 10-3 m e dp = 7,8039 X 10-3 m e esferidades de 0,9510 e 0,9673, respectivamente. Como solução de recobrimento foi utilizada uma solução aquosa polimérica a 50°C. O leito de jorro utilizado foi construído em acrílico e com a possibilidade de variação do ângulo da base inclinada. Os experimentos foram realizados com ângulos de base 30, 45 e 60°, na faixa de temperatura de 70°C a 85°C e vazões de solução de recobrimento na faixa de 7,0 ml/min a 13,0 ml/min. Um atomizador de duplo fluido com mistura externa foi instalado no topo do leito, e a solução de recobrimento foi alimentada em contra-corrente com o ar de jorro. Determinou-se o coeficiente médio de transferência de calor, que foi expresso através do número de Nusselt, Nu, verificando-se que Nu aumenta quando Re e Ws/Wg aumentam e quando Ho/?dp e tg(?/2) diminuem. Foi efetuada uma análise dimensional do processo e os dados experimentais foram ajustados, através dos métodos dos mínimos quadrados, obtendo-se a seguinte correlação: Nu=0,9892.Pr1/3.Re1,6421.(Ws/Wg)¿1,0,7808.(Ho/?dp)¿1,3363.[tg(?/2)]0,1806 O sistema experimental, a formulação da solução e as temperaturas utilizadas no processo mostraram-se adequadas à verificação da variação da massa dos comprimidos com o tempo do processo de recobrimento. Verificou-se uma relação linear do crescimento da partícula com o tempo, sendo esse crescimento função de Ws/Wg. Nas condições estudadas, a temperatura não apresentou influência significativa na taxa de crescimento, kl, e nem na eficiência do processo, ?. Os valores obtidos para eficiência foram considerados satisfatórios, variando entre 57% e 81% para a inclinação de 45°. O melhor ângulo de trabalho foi o de 45°, apresentando boa circulação dos comprimidos levando assim a um recobrimento uniforme e altas taxas de crescimento e eficiência do recobrimento. O recobrimento foi considerado satifatório por observação visual, com boa adesão e não ocorrendo o fenômeno de "peeling", nem penetração da solução
Abstract: The study of fluid-particle heat transfer, particle growth rate, kl, and process efficiency, ?, applied to the coating of tablets on a two-dimensional spouted bed, was the objectives of this work. The used particles were placebos in lenticular shapes of real tablets, with dp = 7,2117 X 10-3 m and dp = 7,8039 X 10-3 m and sphericity equal to 0,9510 and 0,9673 respectively. As for the coating solution, it was used an aqueous polimeric solution at about 50°C. The spouted bed used was built in plexiglass with the likeliness of slant angle variation. The experiments were carried out with three different slant anglesj 30°, 45°, 60°, in a temperature range of 70°C - 85°C and solution flow rate in the range of 7,0 - 13,0 ml/min. A spraying nozzle of double fluid with externa I mixture was installed on the bed top, and the coating solution was fed counter-current to the spout flow. The medium head transfer coeficient was determined, and it was expressed by the non-dimensional Nusselt number, Nu, verifying that Nu increases when Re and Ws/Wg increase and when Ho/?dp and tg(?/2) decrease. It was carried out a dimensional analysis of the process and the experimental data were fit through a least square method, obtaining the following relation: Nu=0,9892.Pr1/3.Re1,6421.(Ws/Wg)¿1,0,7808.(Ho/?dp)¿1,3363.[tg(?/2)]0,1806 The experimental system, the coating solution formulation and the temperature used in the process showed up to be adequa te to the ver if ication of tablets mass var iation concerning the time of coating. A linear relationship between the particle growth and time was verified, and this growth being function of Ws/Wg. As for the temperature, it didn't present any significant influence either upon the growth rate, kl,or on the process efficiency, ?, in the studied conditions. The obtained values for efficiency were considered satisfactory, bearing a variation between 57% and 81% for 45° of falanted angle. The best work angle was 45°, showing high growth rates and coating efficiency. The coating was considered satisfactory on eye observation, with good adhesion with no peeling and no solution penetration either
Mestrado
Engenharia de Processos
Mestre em Engenharia Química
25
Dong, Kai. « High-dimensional covariance matrix estimation with application to Hotelling's tests ». HKBU Institutional Repository, 2015. https://repository.hkbu.edu.hk/etd_oa/191.
Texte intégralRésumé :
In recent years, high-dimensional data sets are widely available in many scientific areas, such as gene expression study, finance and others. Estimating the covariance matrix is a significant issue in such high-dimensional data analysis. This thesis focuses on high-dimensional covariance matrix estimation and its application. First, this thesis focuses on the covariance matrix estimation. In Chapter 2, a new optimal shrinkage estimation of the covariance matrices is proposed. This method is motivated by the quadratic discriminant analysis where many covariance matrices need to be estimated simultaneously. We shrink the sample covariance matrix towards the pooled sample covariance matrix through a shrinkage parameter. Some properties of the optimal shrinkage parameter are investigated and we also provide how to estimate the optimal shrinkage parameter. Simulation studies and real data analysis are also conducted. In Chapter 4, we estimate the determinant of the covariance matrix using some recent proposals for estimating high-dimensional covariance matrix. Specifically, a total of nine covariance matrix estimation methods will be considered for comparison. Through extensive simulation studies, we explore and summarize some interesting comparison results among all compared methods. A few practical guidelines are also made on the sample size, the dimension, and the correlation of the data set for estimating the determinant of high-dimensional covariance matrix. Finally, from a perspective of the loss function, the comparison study in this chapter also serves as a proxy to assess the performance of the covariance matrix estimation. Second, this thesis focuses on the application of high-dimensional covariance matrix estimation. In Chapter 3, we consider to estimate the high-dimensional covariance matrix based on the diagonal matrix of the sample covariance matrix and apply it to the Hotelling’s tests. In this chapter, we propose a shrinkage-based diagonal Hotelling’s test for both one-sample and two-sample cases. We also propose several different ways to derive the approximate null distribution under different scenarios of p and n for our proposed shrinkage-based test. Simulation studies show that the proposed method performs comparably to existing competitors when n is moderate or large, and it is better when n is small. In addition, we analyze four gene expression data sets and they demonstrate the advantage of our proposed shrinkage-based diagonal Hotelling’s test. Apart from the covariance matrix estimation, we also develop a new classification method for a specific type of high-dimensional data, RNA-sequencing data. In Chapter 5, we propose a negative binomial linear discriminant analysis for RNA-Seq data. By Bayes’ rule, we construct the classifier by fitting a negative binomial model, and propose some plug-in rules to estimate the unknown parameters in the classifier. The relationship between the negative binomial classifier and the Poisson classifier is explored, with a numerical investigation of the impact of dispersion on the discriminant score. Simulation results show the superiority of our proposed method. We also analyze four real RNA-Seq data sets to demonstrate the advantage of our method in real-world applications. Keywords: Covariance matrix, Discriminant analysis, High-dimensional data, Hotelling’s test, Log determinant, RNA-sequencing data.
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FORCHINI, PIER FRANCA. « Spontaneity in American English : face - to - face and movie conversation compared ». Doctoral thesis, Università Cattolica del Sacro Cuore, 2009. http://hdl.handle.net/10280/411.
Texte intégralRésumé :
La tesi fornisce uno studio empirico relativo agli elementi linguistici caratterizzanti il parlato faccia-a-faccia e il parlato filmico americano, due domini conversazionali solitamente detti differire in termini di spontaneità, essendo il primo generalmente descritto come la quintessenza del linguaggio parlato (in quanto totalmente spontaneo) e il secondo come non-spontaneo (essendo scritto-per-essere-parlato) e, quindi, non adatto a rappresentare l'uso generale della conversazione. Entrambe le analisi (i.e. quella multi-dimensionale, che offre una panoramica generale dei due domini presi in considerazione, e quella più specifica relativa al comportamento linguistico dell’espressione you know) basate su esempi autentici tratti da corpora dimostrano che, nonostante quanto venga generalmente descritto dalla letteratura a riguardo, conversazione faccia-a-faccia e conversazione filmica hanno molti tratti in comune e confutano l’idea che il linguaggio filmico non possa essere rappresentativo dell'uso generale della conversazione.The present dissertation examines empirically the linguistic features characterizing American face-to-face and movie conversation, two domains which are usually claimed to differ especially in terms of spontaneity. Natural conversation is, indeed, considered the quintessence of the spoken language for it is totally spontaneous, whereas movie conversation is usually described as non-spontaneous, being artificially written-to-be spoken and, thus, not likely to represent the general usage of conversation. In spite of what is generally maintained by the literature, both the Multi-Dimensional analysis and the micro-analysis of the functions of you know based on authentic data retrieved from corpora show that the two conversational domains do not differ to a great extent and thus confutes the claim that movie language has “a very limited value” in that it does not reflect natural conversation and, consequently, is “not likely to be representative of the general usage of conversation”.
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FORCHINI, PIER FRANCA. « Spontaneity in American English : face - to - face and movie conversation compared ». Doctoral thesis, Università Cattolica del Sacro Cuore, 2009. http://hdl.handle.net/10280/411.
Texte intégralRésumé :
La tesi fornisce uno studio empirico relativo agli elementi linguistici caratterizzanti il parlato faccia-a-faccia e il parlato filmico americano, due domini conversazionali solitamente detti differire in termini di spontaneità, essendo il primo generalmente descritto come la quintessenza del linguaggio parlato (in quanto totalmente spontaneo) e il secondo come non-spontaneo (essendo scritto-per-essere-parlato) e, quindi, non adatto a rappresentare l'uso generale della conversazione. Entrambe le analisi (i.e. quella multi-dimensionale, che offre una panoramica generale dei due domini presi in considerazione, e quella più specifica relativa al comportamento linguistico dell’espressione you know) basate su esempi autentici tratti da corpora dimostrano che, nonostante quanto venga generalmente descritto dalla letteratura a riguardo, conversazione faccia-a-faccia e conversazione filmica hanno molti tratti in comune e confutano l’idea che il linguaggio filmico non possa essere rappresentativo dell'uso generale della conversazione.The present dissertation examines empirically the linguistic features characterizing American face-to-face and movie conversation, two domains which are usually claimed to differ especially in terms of spontaneity. Natural conversation is, indeed, considered the quintessence of the spoken language for it is totally spontaneous, whereas movie conversation is usually described as non-spontaneous, being artificially written-to-be spoken and, thus, not likely to represent the general usage of conversation. In spite of what is generally maintained by the literature, both the Multi-Dimensional analysis and the micro-analysis of the functions of you know based on authentic data retrieved from corpora show that the two conversational domains do not differ to a great extent and thus confutes the claim that movie language has “a very limited value” in that it does not reflect natural conversation and, consequently, is “not likely to be representative of the general usage of conversation”.
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Roodaki, Alireza. « Signal decompositions using trans-dimensional Bayesian methods ». Phd thesis, Supélec, 2012. http://tel.archives-ouvertes.fr/tel-00765464.
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This thesis addresses the challenges encountered when dealing with signal decomposition problems with an unknown number of components in a Bayesian framework. Particularly, we focus on the issue of summarizing the variable-dimensional posterior distributions that typically arise in such problems. Such posterior distributions are defined over union of subspaces of differing dimensionality, and can be sampled from using modern Monte Carlo techniques, for instance the increasingly popular Reversible-Jump MCMC (RJ-MCMC) sampler. No generic approach is available, however, to summarize the resulting variable-dimensional samples and extract from them component-specific parameters. One of the main challenges that needs to be addressed to this end is the label-switching issue, which is caused by the invariance of the posterior distribution to the permutation of the components. We propose a novel approach to this problem, which consists in approximating the complex posterior of interest by a "simple"--but still variable-dimensional parametric distribution. We develop stochastic EM-type algorithms, driven by the RJ-MCMC sampler, to estimate the parameters of the model through the minimization of a divergence measure between the two distributions. Two signal decomposition problems are considered, to show the capability of the proposed approach both for relabeling and for summarizing variable dimensional posterior distributions: the classical problem of detecting and estimating sinusoids in white Gaussian noise on the one hand, and a particle counting problem motivated by the Pierre Auger project in astrophysics on the other hand.
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Vohra, Neeru Rani. « Three dimensional statistical graphs, visual cues and clustering ». Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/MQ56213.pdf.
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Lee, Wai Hong. « Variable selection for high dimensional transformation model ». HKBU Institutional Repository, 2010. http://repository.hkbu.edu.hk/etd_ra/1161.
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Ruan, Lingyan. « Statistical analysis of high dimensional data ». Diss., Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/37135.
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This century is surely the century of data (Donoho, 2000). Data analysis has been an emerging activity over the last few decades. High dimensional data is in particular more and more pervasive with the advance of massive data collection system, such as microarrays, satellite imagery, and financial data. However, analysis of high dimensional data is of challenge with the so called curse of dimensionality (Bellman 1961). This research dissertation presents several methodologies in the application of high dimensional data analysis.
The first part discusses a joint analysis of multiple microarray gene expressions. Microarray analysis dates back to Golub et al. (1999). It draws much attention after that. One common goal of microarray analysis is to determine which genes are differentially expressed. These genes behave significantly differently between groups of individuals. However, in microarray analysis, there are thousands of genes but few arrays (samples, individuals) and thus relatively low reproducibility remains. It is natural to consider joint analyses that could combine microarrays from different experiments effectively in order to achieve improved accuracy. In particular, we present a model-based approach for better identification of differentially expressed genes by incorporating data from different studies. The model can accommodate in a seamless fashion a wide range of studies including those performed at different platforms, and/or under different but overlapping biological conditions. Model-based inferences can be done in an empirical Bayes fashion. Because of the information sharing among studies, the joint analysis dramatically improves inferences based on individual analysis. Simulation studies and real data examples are presented to demonstrate the effectiveness of the proposed approach under a variety of complications that often arise in practice.
The second part is about covariance matrix estimation in high dimensional data. First, we propose a penalised likelihood estimator for high dimensional t-distribution. The student t-distribution is of increasing interest in mathematical finance, education and many other applications. However, the application in t-distribution is limited by the difficulty in the parameter estimation of the covariance matrix for high dimensional data. We show that by imposing LASSO penalty on the Cholesky factors of the covariance matrix, EM algorithm can efficiently compute the estimator and it performs much better than other popular estimators.
Secondly, we propose an estimator for high dimensional Gaussian mixture models. Finite Gaussian mixture models are widely used in statistics thanks to its great flexibility. However, parameter estimation for Gaussian mixture models with high dimensionality can be rather challenging because of the huge number of parameters that need to be estimated. For such purposes, we propose a penalized likelihood estimator to specifically address such difficulties. The LASSO penalty we impose on the inverse covariance matrices encourages sparsity on its entries and therefore helps reducing the dimensionality of the problem. We show that the proposed estimator can be efficiently computed via an Expectation-Maximization algorithm. To illustrate the practical merits of the proposed method, we consider its application in model-based clustering and mixture discriminant analysis. Numerical experiments with both simulated and real data show that the new method is a valuable tool in handling high dimensional data.
Finally, we present structured estimators for high dimensional Gaussian mixture models. The graphical representation of every cluster in Gaussian mixture models may have the same or similar structure, which is an important feature in many applications, such as image processing, speech recognition and gene network analysis. Failure to consider the sharing structure would deteriorate the estimation accuracy. To address such issues, we propose two structured estimators, hierarchical Lasso estimator and group Lasso estimator. An EM algorithm can be applied to conveniently solve the estimation problem. We show that when clusters share similar structures, the proposed estimator perform much better than the separate Lasso estimator.
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Schurch, Brandt Roger. « Three-dimensional imaging and analysis of electrical trees ». Thesis, University of Manchester, 2014. https://www.research.manchester.ac.uk/portal/en/theses/threedimensional-imaging-and-analysis-of-electrical-trees(73e032f6-3e6b-4ee9-9cc1-953a11f36cb3).html.
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Electrical trees are micrometre-size tubular channels of degradation in high voltage polymeric insulation, a precursor to failure of electrical power plant. Hence, electrical trees critically affect the reliability of power systems and the performance of new insulation designs. Imaging laboratory-grown electrical trees has been an important tool for studying how trees develop. Commonly, electrical trees prepared in transparent or translucent polymers are imaged using traditional optical methods. Consequently, most of the analysis has been based on two-dimensional (2D) images of trees, thus, valuable information may be lost. However, electrical trees are complex interconnected structures that require a tree-dimensional (3D) approach for more complete analysis. This thesis investigates a method for imaging and analysis of electrical trees to characterise their 3D structure and provide a platform for further modelling. Laboratory created electrical trees were imaged using X-ray Computed Tomography (XCT) and Serial Block-Face Scanning Electron Microscopy (SBFSEM), 3D imaging techniques that provide sub-micrometre spatial resolution. Virtual replicas of the trees, which are the 3D geometrical models representing the real electrical trees, were generated and new indices to characterise the 3D structure of electrical trees were developed. These parameters were indicative of differences in tree growth and thus, they can be used to investigate patterns and classify the structure of electrical trees. The progression of the tree was analysed using cross-sections of the tree that are orthogonal to the growth: the number of tree channels and area covered by them were measured. The fractal dimension of the tree was calculated from the 3D model and from the 2D projections, the latter being lower for all the tree-type structures studied. Parameters from the skeleton of the tree such as number of nodes, segment length, tortuosity and branch angle were measured. Most of the mean segment lengths ranged 6-13 µm, which is in accordance to the 10µm proposed by various tree-growth models. The capabilities of XCT and SBFSEM imaging techniques were evaluated in their application to electrical trees. Bush and branch trees, including early-growth electrical trees (of length 20-40 µm), were analysed and compared using the comprehensive tool of visualisation and characterisation developed. A two-stage tree-growth experiment was conducted to analyse the progression and development of tree branches using XCT: tree channels after the second stage of growth were wider than after the first, while the fractal dimension remained the same. The capabilities of XCT and SBFSEM were tested for imaging electrical trees in optically-opaque materials such as micro and nano-filled epoxy compounds. The general structure of trees in epoxy filled up to 20 wt% micro-silica was observed using both techniques. The use of a virtual replica as the 3D geometrical model for the simulation of the electric field distribution using Finite Element Analysis (FEA) was preliminary explored. A combination of the imaging techniques is proposed for a more complete structural analysis of trees. It is believed that a great impact towards understanding electrical treeing will be achieved using the 3D technical platform developed in this thesis.
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Strehl, Alexander. « Relationship-based clustering and cluster ensembles for high-dimensional data mining ». Thesis, Full text (PDF) from UMI/Dissertation Abstracts International, 2002. http://wwwlib.umi.com/cr/utexas/fullcit?p3088578.
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Imbrasaite, Vaiva. « Continuous dimensional emotion tracking in music ». Thesis, University of Cambridge, 2015. https://www.repository.cam.ac.uk/handle/1810/247917.
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The size of easily-accessible libraries of digital music recordings is growing every day, and people need new and more intuitive ways of managing them, searching through them and discovering new music. Musical emotion is a method of classification that people use without thinking and it therefore could be used for enriching music libraries to make them more user-friendly, evaluating new pieces or even for discovering meaningful features for automatic composition. The field of Emotion in Music is not new: there has been a lot of work done in musicology, psychology, and other fields. However, automatic emotion prediction in music is still at its infancy and often lacks that transfer of knowledge from the other fields surrounding it. This dissertation explores automatic continuous dimensional emotion prediction in music and shows how various findings from other areas of Emotion and Music and Affective Computing can be translated and used for this task. There are four main contributions. Firstly, I describe a study that I conducted which focused on evaluation metrics used to present the results of continuous emotion prediction. So far, the field lacks consensus on which metrics to use, making the comparison of different approaches near impossible. In this study, I investigated people’s intuitively preferred evaluation metric, and, on the basis of the results, suggested some guidelines for the analysis of the results of continuous emotion recognition algorithms. I discovered that root-mean-squared error (RMSE) is significantly preferable to the other metrics explored for the one dimensional case, and it has similar preference ratings to correlation coefficient in the two dimensional case. Secondly, I investigated how various findings from the field of Emotion in Music can be used when building feature vectors for machine learning solutions to the problem. I suggest some novel feature vector representation techniques, testing them on several datasets and several machine learning models, showing the advantage they can bring. Some of the suggested feature representations can reduce RMSE by up to 19% when compared to the standard feature representation, and up to 10-fold improvement for non-squared correlation coefficient. Thirdly, I describe Continuous Conditional Random Fields and Continuous Conditional Neural Fields (CCNF) and introduce their use for the problem of continuous dimensional emotion recognition in music, comparing them with Support Vector Regression. These two models incorporate some of the temporal information that the standard bag-of-frames approaches lack, and are therefore capable of improving the results. CCNF can reduce RMSE by up to 20% when compared to Support Vector Regression, and can increase squared correlation for the valence axis by up to 40%. Finally, I describe a novel multi-modal approach to continuous dimensional music emotion recognition. The field so far has focused solely on acoustic analysis of songs, while in this dissertation I show how the separation of vocals and music and the analysis of lyrics can be used to improve the performance of such systems. The separation of music and vocals can improve the results by up to 10% with a stronger impact on arousal, when compared to a system that uses only acoustic analysis of the whole signal, and the addition of the analysis of lyrics can provide a similar improvement to the results of the valence model.
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MENEZES, M. DE. « THREE-DIMENSIONAL FACIAL ANTHROPOMETRY ». Doctoral thesis, Università degli Studi di Milano, 2010. http://hdl.handle.net/2434/150157.
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The use of 3D surface technology is progressively increasing in health clinics and research centers. Methods of capturing 3D facial surface may obtain more imaging information providing a reliable and fast analysis. Stereophotogrammetry is a promising method of soft-tissue evaluation that allows reliable analysis of craniofacial deformities, providing fundamental parameters to plan and evaluate dental treatments and maxillofacial surgery, so improving the multi-disciplinary and multi-species studies of genotype–phenotype correlations through simple and precise measurements.
In the current study, photogrammetry/stereophotogrammetry systems were used to evaluate soft-tissue facial morphology and dental casts. Three-dimensional images were collected and rebuilt in 3D, using software for rendering images to establish, analyze and compare morphology features of craniofacial structures, and to assess the usage and limitations of these devices. The use and investigation of this system were divided in 4 studies: 1) A photographic system for the three-dimensional study of facial morphology; 2) Accuracy and reproducibility of a 3D stereophotogrammetry imaging system; 3) Digital dental cast placement in 3-dimensional, full-face reconstruction: A technical evaluation and 4) Unilateral Cleft Lip and Palate (UCLP): a 3D evaluation.
The current studies found the used 3D image systems both accurate and repeatable. The 3D devices and the methods analyzed in these studies could therefore be usefully used for clinical analysis in maxillofacial, plastic and esthetic surgery, as well as in all dental fields. The 3D stereophotogrammetric systems have several advantages over direct anthropometry and gradually are becoming into more accessible cost, replacing classical methods to quantify surface topography.
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Donaghy, Richard James. « Dimensional reduction of stress analysis models ». Thesis, Queen's University Belfast, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.263368.
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He, Dahai. « Thermal rectification in one-dimensional nonlinear systems ». HKBU Institutional Repository, 2008. http://repository.hkbu.edu.hk/etd_ra/865.
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Ribokas, Jonas. « Diskrečiojo Le Gall spektro apskaičiavimo dvimačio vaizdo fragmentams algoritmų analizė ». Master's thesis, Lithuanian Academic Libraries Network (LABT), 2011. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2011~D_20110902_093308-24497.
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Darbe analizuojama diskrečioji Le Gall transformacija (DLGT) yra viena iš bangelių transformacijų, kurios naudojamos skaitmeninių vaizdų glaudinime. Vaizdų glaudinimas ypač svarbus, kai kalbama apie vaizdų siuntimą mažo pralaidumo kompiuteriniu kanalu. Šiai problemai spręsti pasitelkiama diskrečioji Le Gall transformacija, bei didelis dėmesys darbe skirtas vaizdo fragmento DLGT spektrui. Šio spektro radimui sukurtas ir realizuotas naujas algoritmas − greitoji procedūra. Palyginamosios analizės metu įrodyta, kad sukurta greitoji procedūra randa vaizdo fragmento DLGT spektrą daugiau nei 50 kartų greičiau nei tiesiogiai taikant DLGT vaizdo fragmentui. Darbo pradžioje aptariamos pagrindinės bangelių ir jų transformacijų savybės. Šių savybių svarba iliustruojama pateiktais pavyzdžiais ir sąsajomis su taikymu praktikoje. Viena iš svarbesnių aptariamų savybių būtų transformacijos lokalizavimas erdvėje. Nors DLGT pilnai netenkina šios savybės, tačiau darbe apžvelgtas dekoreliacijos metodas leidžia išspręsti šią problemą. Be to, pateikiami išsamūs DLGT algoritmai vienmačiams ir dvimačiams vaizdams. Šių algoritmų dėka buvo sukurta programinė įranga, padedanti analizuoti DLGT. Galiausiai darbo pabaigoje pateikiama sukurtos programinės įrangos instrukcija.In this paper the main attention is dedicated to discrete Le Gall transformation (DLGT), the family of discrete wavelets transformations, which usage in the image compression is quite popular. Image compression is very important when it comes to low bandwidth network and computer channels. To deal with this problem the discrete Le Gall wavelets are brought up and focused on the image fragment DLGT spectrum. For calculation of this spectrum the new fast procedure is suggested and realized. In comparative analysis the fast procedure is proved to work more than 50 times faster than applying DLGT direct to image fragment. In the beginning of this paper the main concepts of wavelets and their transformations are analyzed. An importance of these properties is illustrated by examples and applications in practice. One of the most important properties is localization in space. Even though DLGT does not fully meet this property decorrelation technique, introduced in paper, benefits in solving localization problem. Moreover, DLGT algorithms are proposed for one-dimensional and 2-dimensional images. According to these algorithms the new program was created, which is dedicated for image analysis. Finally, in the end of paper the instructions of program are presented.
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Schmid, Frank. « Essays on the large dimensional approximate dynamic factor model / ». Berlin : dissertation.de, 2009. http://www.ub.unibe.ch/content/bibliotheken_sammlungen/sondersammlungen/dissen_bestellformular/index_ger.html.
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Kong, Xiaoli. « High Dimensional Multivariate Inference Under General Conditions ». UKnowledge, 2018. https://uknowledge.uky.edu/statistics_etds/33.
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In this dissertation, we investigate four distinct and interrelated problems for high-dimensional inference of mean vectors in multi-groups.
The first problem concerned is the profile analysis of high dimensional repeated measures. We introduce new test statistics and derive its asymptotic distribution under normality for equal as well as unequal covariance cases. Our derivations of the asymptotic distributions mimic that of Central Limit Theorem with some important peculiarities addressed with sufficient rigor. We also derive consistent and unbiased estimators of the asymptotic variances for equal and unequal covariance cases respectively.
The second problem considered is the accurate inference for high-dimensional repeated measures in factorial designs as well as any comparisons among the cell means. We derive asymptotic expansion for the null distributions and the quantiles of a suitable test statistic under normality. We also derive the estimator of parameters contained in the approximate distribution with second-order consistency. The most important contribution is high accuracy of the methods, in the sense that p-values are accurate up to the second order in sample size as well as in dimension.
The third problem pertains to the high-dimensional inference under non-normality. We relax the commonly imposed dependence conditions which has become a standard assumption in high dimensional inference. With the relaxed conditions, the scope of applicability of the results broadens.
The fourth problem investigated pertains to a fully nonparametric rank-based comparison of high-dimensional populations. To develop the theory in this context, we prove a novel result for studying the asymptotic behavior of quadratic forms in ranks.
The simulation studies provide evidence that our methods perform reasonably well in the high-dimensional situation. Real data from Electroencephalograph (EEG) study of alcoholic and control subjects is analyzed to illustrate the application of the results.
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Valluru, Srividya. « Steady state thermal stress analyses of two-dimensional and three-dimensional solid oxide fuel cells ». Morgantown, W. Va. : [West Virginia University Libraries], 2005. https://etd.wvu.edu/etd/controller.jsp?moduleName=documentdata&jsp%5FetdId=3887.
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Thesis (M.S.)--West Virginia University, 2005.Title from document title page. Document formatted into pages; contains ix, 138 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 90-94).
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Dannenberg, Matthew. « Pattern Recognition in High-Dimensional Data ». Scholarship @ Claremont, 2016. https://scholarship.claremont.edu/hmc_theses/76.
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Vast amounts of data are produced all the time. Yet this data does not easily equate to useful information: extracting information from large amounts of high dimensional data is nontrivial. People are simply drowning in data. A recent and growing source of high-dimensional data is hyperspectral imaging. Hyperspectral images allow for massive amounts of spectral information to be contained in a single image. In this thesis, a robust supervised machine learning algorithm is developed to efficiently perform binary object classification on hyperspectral image data by making use of the geometry of Grassmann manifolds. This algorithm can consistently distinguish between a large range of even very similar materials, returning very accurate classification results with very little training data. When distinguishing between dissimilar locations like crop fields and forests, this algorithm consistently classifies more than 95 percent of points correctly. On more similar materials, more than 80 percent of points are classified correctly. This algorithm will allow for very accurate information to be extracted from these large and complicated hyperspectral images.
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Zhang, Xiang. « Dimensional analysis based CFD modelling for power transformers ». Thesis, University of Manchester, 2017. https://www.research.manchester.ac.uk/portal/en/theses/dimensional-analysis-based-cfd-modelling-for-power-transformers(49cac27d-38b9-4f23-a6ec-b5106422420c).html.
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Reliable thermal modelling approaches are crucial to transformer thermal design and operation. The highest temperature in the winding, usually referred to as the hot-spot temperature, is of the greatest interest because the insulation paper at the hot-spot undergoes the severest thermal ageing, and determines the life expectancy of the transformer insulation. Therefore, the primary objective of transformer thermal design is to control the hot-spot temperature rise over the ambient temperature within certain limit. For liquid-immersed power transformers, the hot-spot temperature rise over the ambient temperature is controlled by the winding geometry, power loss distribution, liquid flow rate and liquid properties. In order to obtain universally applicable thermal modelling results, dimensional analysis is adopted in this PhD thesis to guide computational fluid dynamics (CFD) simulations for disc-type transformer windings in steady state and their experimental verification. The modelling work is split into two parts on oil forced and directed (OD) cooling modes and oil natural (ON) cooling modes. COMSOL software is used for the CFD simulation work For OD cooling modes, volumetric oil flow proportion in each horizontal cooling duct (Pfi) and pressure drop coefficient over the winding (Cpd) are found mainly controlled by the Reynolds number at the winding pass inlet (Re) and the ratio of horizontal duct height to vertical duct width. The correlations for Pfi and Cpd with the dimensionless controlling parameters are derived from CFD parametric sweeps and verified by experimental tests. The effects of different liquid types on the flow distribution and pressure drop are investigated using the correlations derived. Reverse flows at the bottom part of winding passes are shown by both CFD simulations and experimental measurements. The hot-spot factor, H, is interpreted as a dimensionless temperature at the hot-spot and the effects of operational conditions e.g. ambient temperature and loading level on H are analysed. For ON cooling modes, the flow is driven by buoyancy forces and hot-streak dynamics play a vital role in determining fluid flow and temperature distributions. The dimensionless liquid flow and temperature distributions and H are all found to be controlled by Re, Pr and Gr/Re2. An optimal design and operational regime in terms of obtaining the minimum H, is identified from CFD parametric sweeps, where the effects of buoyancy forces are balanced by the effects of inertial forces. Reverse flows are found at the top part of winding passes, opposite to the OD results. The total liquid flow rates of different liquids for the same winding geometry with the same power loss distribution in an ON cooling mode are determined and with these determined total liquid flow rates, the effects of different liquids on fluid flow and temperature distributions are investigated by CFD simulations. The CFD modelling work on disc-type transformer windings in steady state present in this PhD thesis is based on the dimensional analyses on the fluid flow and heat transfer in the windings. Therefore, the results obtained are universally applicable and of the simplest form as well. In addition, the dimensional analyses have provided insight into how the flow and temperature distribution patterns are controlled by the dimensionless controlling parameters, regardless of the transformer operational conditions and the coolant liquid types used.
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Venter, Andre. « Comprehensive two-dimensional supercritical fluid and gas chromatography (SFCxGC) ». Thesis, Pretoria : [s.n.], 2003. http://upetd.up.ac.za/thesis/available/etd-03132003-161136.
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Johnson, Mark Thomas. « Photoelectron spectroscopy of two-dimensional materials and surfaces ». Thesis, University of Cambridge, 1987. https://www.repository.cam.ac.uk/handle/1810/250898.
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Davis, E. J. « Three dimensional topography : Statistical assessment and instrument fidelity ». Thesis, Coventry University, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.379677.
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Li, Hao. « Feature cluster selection for high-dimensional data analysis ». Diss., Online access via UMI:, 2007.
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Villa, A. « Three dimensional geophysical modeling : from physics to numerical simulation ». Doctoral thesis, Università degli Studi di Milano, 2010. http://hdl.handle.net/2434/148440.
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The main objective of this thesis is to provide a comprehensive numerical tool for the three-dimensional simulation of sedimentary basins. We have used a volume averaging technique to obtain a couple of basin-scale mathematical models. We have used some innovative numerical techniques to deal with such models. A multi-fluid implicit tracking technique is developed and integrated with a Stokes solver that is robust with respect to the variations of the coefficients. The movement of the basin boundaries and the evolution of the faults are treated with an Ale and a Finite Volume scheme respectively. Also some mesh refinement methods are used to guarantee a sufficient accuracy. The numerical experiments show a good qualitative agreement with the measured geometry of the sedimentary layers.
(Pubblicata - vedi http://hdl.handle.net/2434/148441)
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Skantzos, Nikolaos Stavrou. « Statistical mechanical analysis of (1 + ∞) dimensional disordered systems ». Thesis, King's College London (University of London), 2001. https://kclpure.kcl.ac.uk/portal/en/theses/statistical-mechanical-analysis-of-1--infinity-dimensional-disordered-systems(b16e7dd9-85df-4e71-b8c6-0c6c28062961).html.
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Gorman, Mark J. « Numerical analysis of one-dimensional waves in generalized thermoelasticity / ». Online version of thesis, 1993. http://hdl.handle.net/1850/11804.
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