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Electric microfield distributions and structure factors in dense plasmasSadykova, Saltanat 17 May 2011 (has links)
Die elektrischen Mikrofeldverteilungen (EMDs) und ihre Auswüchse wurden in einkomponentiger (OCP) Elektron-, zweikomponentigen (TCP) Elektron-Positron-, Wasserstoff- und einwertig ionisierten Alkaliplasmen im Rahmen verschiedener Pseudopotentialmodelle (PM) untersucht und mit sowohl Molekulardynamik (MD) und Monte-Carlo Simulationen als auch mit Experimenten vergliechen. Die verwendeten theoretischen Verfahren zur Berechnung von EMDs gehen zurück auf die von C. A. Iglesias entwickelte Kopplungsparameter Integrationstechnik (KPIT) für OCP und die von J. Ortner et al. vorgeschlagene verallgemeinerte KPIT für TCP. EMDs wurden im Rahmen der abgeschirmten Kelbg-, Deutsch-, Hellmann-Gurskii-Krasko(HGK)-PM untersucht, welche quantenmechanische Effekte, Abschirmungseffekte und die Struktur der Ionenrümpfe (HGK) berücksichtigen. Die Abschirmungseffekte wurden auf Grundlage der Bogoljubov-Born-Green-Kirkwood-Yvon- Methode eingeführt. Wir haben das abgeschirmte HGK-Pseudopotential in der Debye-Näherung sowie in einer mäßig gekoppelten Plasma-Näherung verwendet. Wir haben verschiedene Typen vom asymptotischen Verhalten der Verteilungsauswüchse in Abhangigheit von Plasmaparameter, Plasmatypen und Strahler bestimmt. Der Vergleich der experimentell gewonnenen Daten mit sowohl einem synthetischen Li2+-Lyman-Spektrum als auch mit einer synthetischen Li II 548 nm Linie lassen den Schluss zu, daß die EMD, welche auf der Grundlage der Iglesias-Methode für OCP im HGK-PM und der MD erhalten wurde, eine gute Übereinstimmung mit den experimentellen Werten liefert. Die statischen partiellen und Ladung-Ladung-Strukturfaktoren (SSF) wurden für Alkali- und Be2+-Plasmen unter Verwendung der von G. Gregori et al. beschriebenen Methode berechnet. Die dynamischen Strukturfaktoren (DSF) für Alkaliplasmen wurden unter Verwendung der durch V. M. Adamyan et al. entwickelten Methode der Momente berechnet. Bei beiden Methoden wurde das abgeschirmte HGK-Pseudopotential verwendet. / The electric microfield distributions (EMDs) and its tails have been studied for electron one-component plasma (OCP), electron-positron, hydrogen and single-ionized alkali two-component plasmas (TCP) in a frame of different pseudopotential models (PM) and compared with Molecular Dynamics (MD) and Monte-Carlo simulations as well as with experiments. The theoretical methods used for calculation of EMDs are a coupling-parameter integration technique (CPIT) developed by C. A. Iglesias for OCP and the generalized CPIT proposed by J. Ortner et al. for TCP. We studied the EMDs in a frame of the screened Kelbg, Deutsch, Hellmann-Gurskii-Krasko (HGK) PMs which take into account quantum-mechanical, screening effects and the ion shell structure (HGK) due to the Pauli exclusion principle. The screening effects were introduced on a base of Bogoljubov-Born-Green-Kirkwood-Yvon method. We used the screened HGK pseudopotential in the Debye approximation as well as in a moderately coupled plasma approximation. The influence of the plasma coupling parameter on the EMD along with the ion shell structure was investigated. We determined different types of asymptotic behaviour of EMD tails in dependence on the plasma type, parameters and radiator. Comparison of a synthetic Li2+ Lyman spectrum as well as comparison of a synthetic Li II 548 nm line with experimental data allows us to conclude that the EMD, obtained on a base of the CPIT method for OCP within the HGK PM and MD, provides a good agreement with the experiment. We have calculated the partial and charge-charge static structure factors (SSF) for alkali and Be2+ plasmas using the method described by G. Gregori et al.. We have calculated the dynamic structure factors (DSF) for alkali plasmas using the method of moments developed by V. M. Adamyan et al. In both methods the screened HGK pseudopotential has been used.
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Essays on macroeconomic theory as a guide to economic policyRied, Stefan 15 October 2009 (has links)
Die vorliegende Dissertation zu makroökonomischen Themen beinhaltet einen einleitenden Literaturüberblick, drei eigenständige und voneinander unabhängige Kapitel sowie einen technischen Anhang. In Kapitel zwei wird ein Zwei-Länder Modell einer Währungsunion betrachtet, in dem die gemeinsame Zentralbank die Wohlfahrt der gesamten Währungsunion maximieren will, während die zwei fiskalpolitischen Akteure vergleichbare, aber minimal abweichende länderspezifische Verlustfunktionen zu minimieren suchen. Das Konkurrenzverhalten dieser drei Institutionen wird in sieben spieltheoretischen Szenarien analysiert. Beim Vergleich einer homogenen mit einer heterogenen Währungsunion lassen sich für letztere deutlich höhere Wohlfahrtsverluste relativ zum sozialen Optimum feststellen. Die Szenarien mit den geringsten Wohlfahrtsverlusten sind Kooperation aller drei Institutionen und eine Stackelberg-Führerschaft der Zentralbank. Kapitel drei untersucht, inwieweit das Verhältnis von Immobilienpreise zum Bruttoinlandsprodukt als langfristig konstant und nur auf Grund von Produktivitätsschocks von seinem Mittelwert abweichend angesehen werden kann. Hierzu wird ein Zwei-Sektoren RBC-Modell für den Immobiliensektor und einen Konsumgütersektor erstellt. Es wird gezeigt, dass ein antizipierter, zukünftiger Schock auf das Produktivitätswachstum im Konsumgütersektor eine sofortige, deutliche Erhöhung der Immobilienpreise relativ zum Bruttoinlandsprodukt zur Folge hat. In Kapitel vier wird gefragt, ob ein typisches Neukeynesianisches Modell "sechs große Rätsel der internationalen Makroökonomie" erklären kann. Die sechs Rätsel werden in Bedingungen für erste und zweite Momente übersetzt und fünf wesentliche Modellparameter geschätzt. Das Ergebnis ist erstaunlich gut: unter anderem können die empirischen Beobachtungen zur Heimatpräferenz wiedergegeben und die Schwankungsbreite des realen Wechselkurses deutlich erhöht werden. Handelskosten sind für dieses Ergebnis ein wesentlicher Faktor. / This dissertation consists of an introductory chapter with an extended literature review, three chapters on individual and independent research topics, and an appendix. Chapter 2 uses a two-country model with a central bank maximizing union-wide welfare and two fiscal authorities minimizing comparable, but slightly different country-wide losses. The rivalry between the three authorities is analyzed in seven static games. Comparing a homogeneous with a heterogeneous monetary union, welfare losses relative to the social optimum are found to be significantly larger in a heterogeneous union. The best-performing scenarios are cooperation between all authorities and monetary leadership. The goal of Chapter 3 is to investigate whether or not it is possible to explain the house price to GDP ratio and the house price to stock price ratio as being generally constant, deviating from its respective mean only because of shocks to productivity? Building a two-sector RBC model for residential and non-residential capital, it is shown that an anticipated future shock to productivity growth in the non-residential sector leads to an immediate large increase in house prices relative to GDP. In Chapter 4, it is asked whether a typical New Keynesian Open Economy Model is able to explain "Six Major Puzzles in International Macroeconomics". After translating the six puzzles into moment conditions for the model, I estimate five parameters to fit the moment conditions implied by the data. Given the simplicity of the model, its fit is surprisingly good: among other things, the home bias puzzles can easily be replicated, the exchange rate volatility is formidably increased and the exchange rate correlation pattern is relatively close to realistic values. Trade costs are one important ingredient for this finding.
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Estudo de compostos LiMePO4 (Me=Mg, Co, Ni) através de Ressonância Magnética Nuclear / Studies of LiMePO4 (Me = Mg, Co, Ni) compounds through Nuclear Magnetic ResonanceSilva, Marcos Antonio da 06 October 2000 (has links)
Nesta dissertação é apresentado um estudo dos compostos Li1-3xMgFexPO4 através de Ressonância Magnética Nuclear (7Li e 31P), no intervalo de temperatura de 150 a 410 K. Estudos desses compostos através de técnicas de difração de elétrons e efeito Mossbauer confirmam que os íons Fe entram na rede cristalina na forma Fe3+, substituindo os íons Li+. O comportamento dos espectros de RMN, dos tempos de relaxação spin-rede e da susceptibilidade magnética dos núcleos 7Li e 31P em função da temperatura, em conjunto com medidas de condutividade iônica, indicam que, mesmo com a adição de impurezas Fe3+ na rede, os íons Li+ pouca mobilidade dentro do intervalo de temperatura utilizado. / This work reports a 7Li and 31P nuclear magnetic resonance study in the Li1-3xMgFexPO4 phases between 150 and 410 K. This study, complementary to those made using Mössbauer and magnetic neutron diffraction experiments, confirms that the Fe3+ ions enter as in the lattice, and that they enter substituting Li ions. The behavior of the 7Li e 31P nuclear magnetic resonance spectra, together with ionic conductivity measurements, show that no Li mobility occurs in temperature range studied even with the addition of the Fe impurity.
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Estudo de compostos LiMePO4 (Me=Mg, Co, Ni) através de Ressonância Magnética Nuclear / Studies of LiMePO4 (Me = Mg, Co, Ni) compounds through Nuclear Magnetic ResonanceMarcos Antonio da Silva 06 October 2000 (has links)
Nesta dissertação é apresentado um estudo dos compostos Li1-3xMgFexPO4 através de Ressonância Magnética Nuclear (7Li e 31P), no intervalo de temperatura de 150 a 410 K. Estudos desses compostos através de técnicas de difração de elétrons e efeito Mossbauer confirmam que os íons Fe entram na rede cristalina na forma Fe3+, substituindo os íons Li+. O comportamento dos espectros de RMN, dos tempos de relaxação spin-rede e da susceptibilidade magnética dos núcleos 7Li e 31P em função da temperatura, em conjunto com medidas de condutividade iônica, indicam que, mesmo com a adição de impurezas Fe3+ na rede, os íons Li+ pouca mobilidade dentro do intervalo de temperatura utilizado. / This work reports a 7Li and 31P nuclear magnetic resonance study in the Li1-3xMgFexPO4 phases between 150 and 410 K. This study, complementary to those made using Mössbauer and magnetic neutron diffraction experiments, confirms that the Fe3+ ions enter as in the lattice, and that they enter substituting Li ions. The behavior of the 7Li e 31P nuclear magnetic resonance spectra, together with ionic conductivity measurements, show that no Li mobility occurs in temperature range studied even with the addition of the Fe impurity.
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Development aid and its impact on poverty reduction in developing countries : a dynamic panel data approachMahembe, Edmore 08 1900 (has links)
Foreign aid has been used on the one hand by donors as an important international relations
policy tool and on the other hand by developing countries as a source of funds for development.
Since its inception in the 1940s, foreign aid has been one of the most researched topics in
development economics. This study adds to this growing aid effectiveness literature, with a
particular focus on the under-researched relationship between foreign aid and extreme poverty.
The main empirical assessment is based on a sample of 120 developing countries from 1981 to
2013. The study had two main objectives, namely: (i) to estimate the impact of foreign aid on
poverty reduction and (ii) to examine the direction of causality between foreign aid and poverty
in developing countries. From these two broad objectives, there are six specific objectives,
which include to: (i) examine the overall impact of foreign aid (total official development
assistance) on extreme poverty, (ii) investigate the impact of different proxies of foreign aid on
the three proxies of extreme poverty, (iii) assess whether political freedom (democracy) or
economic freedom enhances the effectiveness of foreign aid, (iv) compare the impact of foreign
aid on extreme poverty by developing country income groups, and (v) examine the direction
of causality between extreme poverty and foreign aid. To achieve these objectives, the study
employed two main dynamic panel data econometric estimation methods, namely the systemgeneralised
method of moments (SGMM) technique and the panel vector error correction
model (VECM) Granger causality framework. While the SGMM was used to assess the impact
of foreign aid on extreme poverty, the panel VECM Granger causality was used to examine the
direction of causality between foreign aid poverty. The SGMM was used because of its ability
to deal with endogeneity by controlling for simultaneity and unobserved heterogeneity,
whereas the panel VECM was preferred because the variables were stationary and cointegrated. / Economics / D. Phil. (Economics)
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Computational fluid dynamics multiscale modelling of bubbly flow. A critical study and new developments on volume of fluid, discrete element and two-fluid methodsPeña Monferrer, Carlos 06 November 2017 (has links)
The study and modelling of two-phase flow, even the simplest ones such as the bubbly flow, remains a challenge that requires exploring the physical phenomena from different spatial and temporal resolution levels. CFD (Computational Fluid Dynamics) is a widespread and promising tool for modelling, but nowadays, there is no single approach or method to predict the dynamics of these systems at the different resolution levels providing enough precision of the results. The inherent difficulties of the events occurring in this flow, mainly those related with the interface between phases, makes that low or intermediate resolution level approaches as system codes (RELAP, TRACE, ...) or 3D TFM (Two-Fluid Model) have significant issues to reproduce acceptable results, unless well-known scenarios and global values are considered. Instead, methods based on high resolution level such as Interfacial Tracking Method (ITM) or Volume Of Fluid (VOF) require a high computational effort that makes unfeasible its use in complex systems.
In this thesis, an open-source simulation framework has been designed and developed using the OpenFOAM library to analyze the cases from microescale to macroscale levels. The different approaches and the information that is required in each one of them have been studied for bubbly flow. In the first part, the dynamics of single bubbles at a high resolution level have been examined through VOF. This technique has allowed to obtain accurate results related to the bubble formation, terminal velocity, path, wake and instabilities produced by the wake. However, this approach has been impractical for real scenarios with more than dozens of bubbles. Alternatively, this thesis proposes a CFD Discrete Element Method (CFD-DEM) technique, where each bubble is represented discretely. A novel solver for bubbly flow has been developed in this thesis. This includes a large number of improvements necessary to reproduce the bubble-bubble and bubble-wall interactions, turbulence, velocity seen by the bubbles, momentum and mass exchange term over the cells or bubble expansion, among others. But also new implementations as an algorithm to seed the bubbles in the system have been incorporated. As a result, this new solver gives more accurate results as the provided up to date.
Following the decrease on resolution level, and therefore the required computational resources, a 3D TFM have been developed with a population balance equation solved with an implementation of the Quadrature Method Of Moments (QMOM). The solver is implemented with the same closure models as the CFD-DEM to analyze the effects involved with the lost of information due to the averaging of the instantaneous Navier-Stokes equation. The analysis of the results with CFD-DEM reveals the discrepancies found by considering averaged values and homogeneous flow in the models of the classical TFM formulation. Finally, for the lowest resolution level approach, the system code RELAP5/MOD3 is used for modelling the bubbly flow regime. The code has been modified to reproduce properly the two-phase flow characteristics in vertical pipes, comparing the performance of the calculation of the drag term based on drift-velocity and drag coefficient approaches. / El estudio y modelado de flujos bifásicos, incluso los más simples como el bubbly flow, sigue siendo un reto que conlleva aproximarse a los fenómenos físicos que lo rigen desde diferentes niveles de resolución espacial y temporal. El uso de códigos CFD (Computational Fluid Dynamics) como herramienta de modelado está muy extendida y resulta prometedora, pero hoy por hoy, no existe una única aproximación o técnica de resolución que permita predecir la dinámica de estos sistemas en los diferentes niveles de resolución, y que ofrezca suficiente precisión en sus resultados. La dificultad intrínseca de los fenómenos que allí ocurren, sobre todo los ligados a la interfase entre ambas fases, hace que los códigos de bajo o medio nivel de resolución, como pueden ser los códigos de sistema (RELAP, TRACE, etc.) o los basados en aproximaciones 3D TFM (Two-Fluid Model) tengan serios problemas para ofrecer resultados aceptables, a no ser que se trate de escenarios muy conocidos y se busquen resultados globales. En cambio, códigos basados en alto nivel de resolución, como los que utilizan VOF (Volume Of Fluid), requirieren de un esfuerzo computacional tan elevado que no pueden ser aplicados a sistemas complejos.
En esta tesis, mediante el uso de la librería OpenFOAM se ha creado un marco de simulación de código abierto para analizar los escenarios desde niveles de resolución de microescala a macroescala, analizando las diferentes aproximaciones, así como la información que es necesaria aportar en cada una de ellas, para el estudio del régimen de bubbly flow. En la primera parte se estudia la dinámica de burbujas individuales a un alto nivel de resolución mediante el uso del método VOF (Volume Of Fluid). Esta técnica ha permitido obtener resultados precisos como la formación de la burbuja, velocidad terminal, camino recorrido, estela producida por la burbuja e inestabilidades que produce en su camino. Pero esta aproximación resulta inviable para entornos reales con la participación de más de unas pocas decenas de burbujas. Como alternativa, se propone el uso de técnicas CFD-DEM (Discrete Element Methods) en la que se representa a las burbujas como partículas discretas. En esta tesis se ha desarrollado un nuevo solver para bubbly flow en el que se han añadido un gran número de nuevos modelos, como los necesarios para contemplar los choques entre burbujas o con las paredes, la turbulencia, la velocidad vista por las burbujas, la distribución del intercambio de momento y masas con el fluido en las diferentes celdas por cada una de las burbujas o la expansión de la fase gaseosa entre otros. Pero también se han tenido que incluir nuevos algoritmos como el necesario para inyectar de forma adecuada la fase gaseosa en el sistema. Este nuevo solver ofrece resultados con un nivel de resolución superior a los desarrollados hasta la fecha.
Siguiendo con la reducción del nivel de resolución, y por tanto los recursos computacionales necesarios, se efectúa el desarrollo de un solver tridimensional de TFM en el que se ha implementado el método QMOM (Quadrature Method Of Moments) para resolver la ecuación de balance poblacional. El solver se desarrolla con los mismos modelos de cierre que el CFD-DEM para analizar los efectos relacionados con la pérdida de información debido al promediado de las ecuaciones instantáneas de Navier-Stokes. El análisis de resultados de CFD-DEM permite determinar las discrepancias encontradas por considerar los valores promediados y el flujo homogéneo de los modelos clásicos de TFM. Por último, como aproximación de nivel de resolución más bajo, se investiga el uso uso de códigos de sistema, utilizando el código RELAP5/MOD3 para analizar el modelado del flujo en condiciones de bubbly flow. El código es modificado para reproducir correctamente el flujo bifásico en tuberías verticales, comparando el comportamiento de aproximaciones para el cálculo del término d / L'estudi i modelatge de fluxos bifàsics, fins i tot els més simples com bubbly flow, segueix sent un repte que comporta aproximar-se als fenòmens físics que ho regeixen des de diferents nivells de resolució espacial i temporal. L'ús de codis CFD (Computational Fluid Dynamics) com a eina de modelatge està molt estesa i resulta prometedora, però ara per ara, no existeix una única aproximació o tècnica de resolució que permeta predir la dinàmica d'aquests sistemes en els diferents nivells de resolució, i que oferisca suficient precisió en els seus resultats. Les dificultat intrínseques dels fenòmens que allí ocorren, sobre tots els lligats a la interfase entre les dues fases, fa que els codis de baix o mig nivell de resolució, com poden ser els codis de sistema (RELAP,TRACE, etc.) o els basats en aproximacions 3D TFM (Two-Fluid Model) tinguen seriosos problemes per a oferir resultats acceptables , llevat que es tracte d'escenaris molt coneguts i se persegueixen resultats globals. En canvi, codis basats en alt nivell de resolució, com els que utilitzen VOF (Volume Of Fluid), requereixen d'un esforç computacional tan elevat que no poden ser aplicats a sistemes complexos.
En aquesta tesi, mitjançant l'ús de la llibreria OpenFOAM s'ha creat un marc de simulació de codi obert per a analitzar els escenaris des de nivells de resolució de microescala a macroescala, analitzant les diferents aproximacions, així com la informació que és necessària aportar en cadascuna d'elles, per a l'estudi del règim de bubbly flow. En la primera part s'estudia la dinàmica de bambolles individuals a un alt nivell de resolució mitjançant l'ús del mètode VOF. Aquesta tècnica ha permès obtenir resultats precisos com la formació de la bambolla, velocitat terminal, camí recorregut, estela produida per la bambolla i inestabilitats que produeix en el seu camí. Però aquesta aproximació resulta inviable per a entorns reals amb la participació de més d'unes poques desenes de bambolles. Com a alternativa en aqueix cas es proposa l'ús de tècniques CFD-DEM (Discrete Element Methods) en la qual es representa a les bambolles com a partícules discretes. En aquesta tesi s'ha desenvolupat un nou solver per a bubbly flow en el qual s'han afegit un gran nombre de nous models, com els necessaris per a contemplar els xocs entre bambolles o amb les parets, la turbulència, la velocitat vista per les bambolles, la distribució de l'intercanvi de moment i masses amb el fluid en les diferents cel·les per cadascuna de les bambolles o els models d'expansió de la fase gasosa entre uns altres. Però també s'ha hagut d'incloure nous algoritmes com el necessari per a injectar de forma adequada la fase gasosa en el sistema. Aquest nou solver ofereix resultats amb un nivell de resolució superior als desenvolupat fins la data.
Seguint amb la reducció del nivell de resolució, i per tant els recursos computacionals necessaris, s'efectua el desenvolupament d'un solver tridimensional de TFM en el qual s'ha implementat el mètode QMOM (Quadrature Method Of Moments) per a resoldre l'equació de balanç poblacional. El solver es desenvolupa amb els mateixos models de tancament que el CFD-DEM per a analitzar els efectes relacionats amb la pèrdua d'informació a causa del promitjat de les equacions instantànies de Navier-Stokes. L'anàlisi de resultats de CFD-DEM permet determinar les discrepàncies ocasionades per considerar els valors promitjats i el flux homogeni dels models clàssics de TFM. Finalment, com a aproximació de nivell de resolució més baix, s'analitza l'ús de codis de sistema, utilitzant el codi RELAP5/MOD3 per a analitzar el modelatge del fluxos en règim de bubbly flow. El codi és modificat per a reproduir correctament les característiques del flux bifàsic en canonades verticals, comparant el comportament d'aproximacions per al càlcul del terme de drag basades en velocitat de drift flux model i de les basades en coe / Peña Monferrer, C. (2017). Computational fluid dynamics multiscale modelling of bubbly flow. A critical study and new developments on volume of fluid, discrete element and two-fluid methods [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/90493
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Contribution à la statistique spatiale et l'analyse de données fonctionnelles / Contribution to spatial statistics and functional data analysisAhmed, Mohamed Salem 12 December 2017 (has links)
Ce mémoire de thèse porte sur la statistique inférentielle des données spatiales et/ou fonctionnelles. En effet, nous nous sommes intéressés à l’estimation de paramètres inconnus de certains modèles à partir d’échantillons obtenus par un processus d’échantillonnage aléatoire ou non (stratifié), composés de variables indépendantes ou spatialement dépendantes.La spécificité des méthodes proposées réside dans le fait qu’elles tiennent compte de la nature de l’échantillon étudié (échantillon stratifié ou composé de données spatiales dépendantes).Tout d’abord, nous étudions des données à valeurs dans un espace de dimension infinie ou dites ”données fonctionnelles”. Dans un premier temps, nous étudions les modèles de choix binaires fonctionnels dans un contexte d’échantillonnage par stratification endogène (échantillonnage Cas-Témoin ou échantillonnage basé sur le choix). La spécificité de cette étude réside sur le fait que la méthode proposée prend en considération le schéma d’échantillonnage. Nous décrivons une fonction de vraisemblance conditionnelle sous l’échantillonnage considérée et une stratégie de réduction de dimension afin d’introduire une estimation du modèle par vraisemblance conditionnelle. Nous étudions les propriétés asymptotiques des estimateurs proposées ainsi que leurs applications à des données simulées et réelles. Nous nous sommes ensuite intéressés à un modèle linéaire fonctionnel spatial auto-régressif. La particularité du modèle réside dans la nature fonctionnelle de la variable explicative et la structure de la dépendance spatiale des variables de l’échantillon considéré. La procédure d’estimation que nous proposons consiste à réduire la dimension infinie de la variable explicative fonctionnelle et à maximiser une quasi-vraisemblance associée au modèle. Nous établissons la consistance, la normalité asymptotique et les performances numériques des estimateurs proposés.Dans la deuxième partie du mémoire, nous abordons des problèmes de régression et prédiction de variables dépendantes à valeurs réelles. Nous commençons par généraliser la méthode de k-plus proches voisins (k-nearest neighbors; k-NN) afin de prédire un processus spatial en des sites non-observés, en présence de co-variables spatiaux. La spécificité du prédicteur proposé est qu’il tient compte d’une hétérogénéité au niveau de la co-variable utilisée. Nous établissons la convergence presque complète avec vitesse du prédicteur et donnons des résultats numériques à l’aide de données simulées et environnementales.Nous généralisons ensuite le modèle probit partiellement linéaire pour données indépendantes à des données spatiales. Nous utilisons un processus spatial linéaire pour modéliser les perturbations du processus considéré, permettant ainsi plus de flexibilité et d’englober plusieurs types de dépendances spatiales. Nous proposons une approche d’estimation semi paramétrique basée sur une vraisemblance pondérée et la méthode des moments généralisées et en étudions les propriétés asymptotiques et performances numériques. Une étude sur la détection des facteurs de risque de cancer VADS (voies aéro-digestives supérieures)dans la région Nord de France à l’aide de modèles spatiaux à choix binaire termine notre contribution. / This thesis is about statistical inference for spatial and/or functional data. Indeed, weare interested in estimation of unknown parameters of some models from random or nonrandom(stratified) samples composed of independent or spatially dependent variables.The specificity of the proposed methods lies in the fact that they take into considerationthe considered sample nature (stratified or spatial sample).We begin by studying data valued in a space of infinite dimension or so-called ”functionaldata”. First, we study a functional binary choice model explored in a case-controlor choice-based sample design context. The specificity of this study is that the proposedmethod takes into account the sampling scheme. We describe a conditional likelihoodfunction under the sampling distribution and a reduction of dimension strategy to definea feasible conditional maximum likelihood estimator of the model. Asymptotic propertiesof the proposed estimates as well as their application to simulated and real data are given.Secondly, we explore a functional linear autoregressive spatial model whose particularityis on the functional nature of the explanatory variable and the structure of the spatialdependence. The estimation procedure consists of reducing the infinite dimension of thefunctional variable and maximizing a quasi-likelihood function. We establish the consistencyand asymptotic normality of the estimator. The usefulness of the methodology isillustrated via simulations and an application to some real data.In the second part of the thesis, we address some estimation and prediction problemsof real random spatial variables. We start by generalizing the k-nearest neighbors method,namely k-NN, to predict a spatial process at non-observed locations using some covariates.The specificity of the proposed k-NN predictor lies in the fact that it is flexible and allowsa number of heterogeneity in the covariate. We establish the almost complete convergencewith rates of the spatial predictor whose performance is ensured by an application oversimulated and environmental data. In addition, we generalize the partially linear probitmodel of independent data to the spatial case. We use a linear process for disturbancesallowing various spatial dependencies and propose a semiparametric estimation approachbased on weighted likelihood and generalized method of moments methods. We establishthe consistency and asymptotic distribution of the proposed estimators and investigate thefinite sample performance of the estimators on simulated data. We end by an applicationof spatial binary choice models to identify UADT (Upper aerodigestive tract) cancer riskfactors in the north region of France which displays the highest rates of such cancerincidence and mortality of the country.
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