Zugl.: Paderborn, Universiẗat, Diss., 2001.

Zugl.: Berlin, Techn. Univ., Diss., 2007

Inaug.-Diss. Recht Freiburg i. Ue., ca 1924. / Promotionsjahr dem Verz. der Schweiz. Hochschulschriften entnommen.

Certaines données satellitaires ne sont pas utilisées à cause des acquisitions bruitées qui ne reflètent pas les distributions des grandeurs géophysiques du sol, telle que l’humidité du sol. La cause primordiale dans les micro-ondes passives vient des interférences radio fréquence (RFI). Ainsi, les températures apparentes mesurées par un satellite comme SMOS par exemple atteignent souvent des valeurs qui conduisent à des échecs d’inversion de l’humidité du sol. L’objectif de notre projet est d’étudier le phénomène des RFI à petite échelle, son impact sur les micro-ondes passives en bande L à partir des mesures au sol réalisées à l’aide de radiomètres. Une fois l’impact caractérisé de manière rigoureuse, une méthode de filtrage adaptatif a été développée pour corriger les effets. Le projet est composé de trois parties principales. La mise en place d’une expérimentation est réalisée afin de faire des mesures au sol à l’aide de deux radiomètres en bande L. Les mesures sont faites dans des conditions variables et plusieurs scénarios ont été considérés. Ensuite, les données sont collectées et analysées. Cette phase a abouti au développement d’un filtre qui permet d’atténuer l’effet des RFI sur les températures de brillance bruitées. Enfin, le filtre proposé dans le projet a été appliqué sur des données aéroportées en bande L prises sur le site Boreal Ecosystem Research and Monitoring Sites (BERMS) en Saskatchewan. L’expérimentation s’est déroulée à la station SIRENE de l’Université de Sherbrooke. Les instruments ont été mis en place et les radiomètres ont été calibrés en premier lieu pour s’assurer de la fiabilité des mesures. L’émetteur a servi comme une source d’interférence pour les radiomètres. Il était placé à des positions différentes vis-à-vis de ces derniers, et émettait à des puissances variables. Les différents scénarios considérés étaient utiles pour étudier l’effet de la position de la source RFI, ainsi que l’effet de la puissance émise par celle-là sur les températures mesurées par les radiomètres. Pour les mesures, nous avons utilisé un radiomètre multi-bandes qui nous a permis d’étudier l’impact de la bande passante sur les RFI. L’analyse et le traitement des données prises ont conduit au développement d’un filtre coupe-bande permettant de corriger les températures bruitées lorsque les caractéristiques du bruit sont connues. Ce filtre a été appliqué sur des données aéroportées bruitées. Le bruit a pu être atténué pour les températures en polarisation V. Les résultats de l’application du filtre sont satisfaisants dans l’ensemble malgré le volume important de données bruitées sur la zone d’étude. En ce qui concerne les données de la polarisation H, elles n’ont pu être corrigées, car elles étaient presque entièrement bruitées. Le mémoire porte sur une expérimentation originale, car les expériences du genre sont très rares dans la littérature. L’étude s’appuie sur deux radiomètres en bande L, ce qui est très particulier, compte tenu de la rareté de ces instruments.

Today’s thin-film passive components such as capacitors and inductors are limited to low volumetric density and large form-factors that pose as major roadblock to miniaturization of the power modules. These components are also placed far away from the IC’s leading to large interconnect parasitics and lower operating frequencies. Novel thin-film technologies with high densities and small form-factors are, therefore, required to enable miniaturization and performance at high frequencies. Glass- and silicon- based interposer technologies that utilize vertical through-via interconnections have shown way to improve power distribution network (PDN) performance with thin power-ground planes. However, integration of ultra-high density capacitors in such substrates has not yet been demonstrated. This thesis addresses these challenges with tantalum-based, silicon-integrated, ultrathin, high-density capacitors at higher operating frequencies with lower leakage properties (<0.01µA/µF). The anodization kinetics of tantalum pentoxide and the underlying leakage current mechanisms are investigated to provide optimal process guidelines. The thin-film Ta capacitors demonstrated capacitance density of 0.1 µF/mm2 at 1-10 MHz in form-factors of 50 µm, which corresponds to 6X higher volumetric density relative to commercial tantalum capacitors. An innovative approach to address incompatibility of tantalum electrodes with substrates is pursued by prefabricating the electrodes on a free-standing foil, which are then transferred onto the active wafer to form the capacitors on Si. The integration approach is designed to embed these thin tantalum capacitors on alternative substrates such as organic, glass or silicon, with copper via interconnections for lower parasitics. The thesis also explores titanium-based high-density capacitors with high-permittivity titania dielectric as a potential alternate high-density capacitor technology.

Multilayer embedded passives (resistors, inductors, and capacitors) on a printed wiring board can help to meet high performance requirements at a low cost and at a smaller size. Such an integration of embedded passives has new challenges with respect to design, materials, manufacturing, thermal management and reliability. As the area of integral passives on printed circuit boards is relatively new, there is inadequate literature on the thermo-mechanical reliability of integral passives. Therefore, there is a compelling need to understand the thermo-mechanical reliability of integral passives through the development of physics-based models as well as through experiments, and this thesis aims to develop such an experimental and theoretical program to study the thermo-mechanical reliability of integral passives.. As integral passives are often composite layers with dissimilar material properties compared to the other layers in the integral substrate, it is essential to ensure that RLC characteristics of the embedded passives do not deteriorate with thermal cycling due to thermo-mechanical deformations. This thesis aims to study the changes in the passive characteristics due to the thermally-induced deformations. Embedded capacitors and inductors have been looked at specifically in this research. Multi-field physics-based models have been constructed to determine the change in electrical parameters after thermal cycling. The thermo-mechanical models assume direction-dependent material properties for the board substrate and interconnect copper layers and temperature-dependent properties for interlayer dielectric and passive layers. Using the deformed geometry, the electrical characteristics have been determined at low frequency. In parallel to the models, test vehicle substrates have been subjected to 1000 thermal cycles between -55??o 125??nd high humidity and temperature conditions at 85??5RH for 500 hours, and it has been observed that there are significant changes in the electrical parameters. The results obtained from the physics-based simulations have been validated against the measured electrical characteristics from the fabricated functional test boards that have been thermal cycled.

The thesis is mainly divided into three parts. The first part will discuss about structures, manufacture, and design flow of embedded passives in organic and flexible substrates, and the results of measurement and electromagnetic (EM) simulation will be compared as well. Second part will discuss the theory and the process of establishing broadband model, and the broadband model will be compared to Pi model and EM simulation. In the third part, we will try to design embedded bandpass filters in organic substrate by the experience of establishing the library of embedded passives. Because of lacking of the fabrication of large capacitance devices in organic substrate, we design bandpass filters by using T type in order to limit the lump devices in the larger inductance and smaller capacitance. The final result of the filters are small in size and have high performance, thus they can be well applied to the RF system in chip (SIP) of wireless communication.

L'instabilité de modulation (IM) en optique est un processus non-linéaire responsable de l'amplification exponentielle d'une faible perturbation périodique au dépend d'une onde porteuse de forte puissance, cela en raison du parfait équilibre entre la dispersion et la non linéarité. Dans les cavités optiques passives, la superposition entre le champ injecté dans le système et le champ intra-cavité ajoute un degré de liberté supplémentaire à ce mécanisme, ce qui enrichit sa dynamique. Dans cette thèse, nous avons principalement mené des études expérimentales de l’IM dans de tels dispositifs faits de fibres optiques, dans des régimes inexplorés. En particulier, nous avons étudié expérimentalement ce processus dans des cavités fonctionnant en régime de dispersion faible. Nous avons montré que la dynamique de l'IM dans un tel régime est fortement modifiée par rapport à celle de l'IM standard dans les cavités. Nous avons également étudié la dynamique temporelle de l'IM montrant que le motif temporel généré peut présenter deux comportements distincts. Une partie de ces travaux est également consacrée à l’étude expérimentale du mécanisme de gain induit par les pertes. Dans des conditions spécifiques, ce processus peut générer de l'IM ainsi que des peignes de fréquence ajustables. Ces études sont en bon accord avec les modèles théoriques et les simulations numériques. Dans la dernière partie de ce travail, nous avons exploré analytiquement le processus de l’IM amorcée de façon cohérente. Nous avons montré que la dynamique du processus est sensible à la phase, ce que nous confirmons expérimentalement en enregistrant l'évolution de la puissance et de la phase des ondes impliquées dans le processus. / Modulation instability (MI) in optics is a nonlinear process where a weak periodic perturbation exponentially grows at the expanse of a strong carrier wave as a result of the perfect balance between dispersion and non-linearity. In passive optical cavities, the coherent superposition between the driving field and the intra-cavity field adds a extra-degree of freedom to this mechanism that enriches its dynamics. In this thesis, we mostly led experimental study of MI in such devices made of optical fibers in unexplored regimes. In particular, we experimentally investigated this process in cavities that operate under weak normal dispersion. We showed that the MI dynamics in such regime is strongly modified compared to standard MI in cavities. We also studied the real-time dynamics of MI in the temporal domain highlighting that the generated temporal pattern can exhibit two distinct behaviors. A part of this work is also dedicated to the experimental study of the gain through loss mechanism. Under specific conditions this process can generate MI and tunable optical frequency combs. These studies are in pretty good agreement with theoretical models and numerical simulations. Finally, we explored analytically the process of coherent seeded MI. We reported that the dynamics of the process is phase-sensitive, which was confirmed experimentally by recording the power and phase evolution of the waves involved in the process.

Thesis (MA)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: This study focuses on the grammatical properties and syntactic derivation of KRY (“get”)-passives in Afrikaans. Analyses of the corresponding phenomenon in other West-Germanic languages are examined and used as background for the study. The aim of the study is to provide a minimalist analysis of the internal structure of Afrikaans KRY-passives; no such analysis has to date been attempted within the framework of Minimalist Syntax. As an introduction to the phenomenon in Afrikaans, some grammatical background about kry and its syntactic distribution is provided, with special attention paid to the use of this verb in passive constructions. A new analysis of Afrikaans KRY-passives is put forward involving a small clause structure and a light verb component. The main hypothesis of the analysis is that eventive and stative KRY-passives are derived in basically the same manner, the important difference being the presence of a [process] and a [stative] feature, respectively, on the small clause light verb. This hypothesis provides support for the idea that the eventual eventive or stative interpretation of the structure is a consequence of the derivational process rather than being based on lexical features that are already present at the start of the derivation. / AFRIKAANSE OPSOMMING: Hierdie studie fokus op die grammatikale eienskappe en sintaktiese afleiding van KRY-passiewe in Afrikaans. Analises van die ooreenstemmende verskynsel in ander Wes-Germaanse tale word ondersoek en as vertrekpunt vir die studie gebruik. Die doel van die studie is om ‟n minimalistiese analise van die interne struktuur van Afrikaanse KRY-passiewe te ontwikkel; so ‟n analise is nog nie tevore binne die raamwerk van Minimalistiese Sintaksis aangebied nie. As algemene inleiding tot die verskynsel in Afrikaans, word enkele aspekte van kry se grammatikale eienskappe en sintaktiese verspreiding beskryf, met besondere klem op die gebruik van hierdie werkwoord in passiefkonstruksies. ‟n Nuwe analise van KRY-passiewe in Afrikaans word voorgestel, een wat gebruik maak van ‟n beknopte sin (“small clause”)-struktuur en ‟n ligte werkwoord (“light verb”)-komponent. Die vernaamste hipotese van die analise is dat gebeurtenis (“eventive”) en toestand (oftewel statief, “stative”) KRY-passiewe wesenlik op dieselfde manier afgelei word, met een belangrike verskil, naamlik die teenwoordigheid van, onderskeidelik, ‟n [proses]- en ‟n [statief]-kenmerk by die beknopte sin se ligte werkwoord. Dié hipotese verleen steun aan die idee dat die uiteindelike gebeurtenis- of toestand-interpretasie van die struktuur die gevolg is van die afleidingsproses, en dus nie gebaseer is op leksikale kenmerke wat reeds teenwoordig is by die aanvang van die afleiding nie.

[pt] Esta dissertação investiga a aquisição das passivas, trazendo um tratamento conciliador entre métrica de computação e demandas de processamento para se pensar a aquisição dessas estruturas. As análises formais da Teoria Linguística Gerativa (Boeckx, 1998; Collins, 2005) são revisitadas sob o enfoque das distinções aventadas pelo Modelo Integrado da Computação on-line (Corrêa E Augusto, 2007; 2011), buscando-se adequá-las às peculiaridades do processamento em tempo real. Nossa hipótese é de que a maior complexidade associada à estrutura de uma passiva eventiva implicaria a existência de movimento com custo computacional mensurável, que seria responsável pela dificuldade das crianças com passivas verbais. A ausência de movimento do tipo relevante em construções como passivas adjetivas, com características copulares, explicaria como a criança é inicialmente capaz de lidar com passivas curtas agentivas, assumindo-se que esta tende a não tomar como essencial o uso de diferentes auxiliares da sua gramática alvo. Três experimentos psicolinguísticos buscaram investigar as hipóteses aventadas. Os dois primeiros apontam dificuldade em todas as passivas verbais do Português, exceto as curtas agentivas e, também, a relevância de traços aspectuais e semânticos para que o processamento de certas passivas seja licenciado na interface com o sistema conceptual-intencional como uma derivação mais simples do que as passivas verbais. O último experimento avaliou a capacidade de distinção entre os diferentes auxiliares envolvidos na derivação de sentenças passivas curtas. Os resultados são compatíveis com as hipóteses e sugerem que a criança valer-se-ia de construções adjetivas para alcançar a plena aquisição das passivas verbais. / [en] This study investigates the acquisition of the passive structure from the point of view of a conciliatory approach between computational metrics and processing demands. The formal analyses from Generative Linguistic Theory (Boeckx, 1998; Collins, 2005) are revisited and made compatible to the distinctions proposed by the Integrated Model of on-line computation (Corrêa AND Augusto, 2007; 2011) -Modelo Integrado da Computação on-line, considering the peculiarities of on-line processing. Our hypothesis is that the structural complexity associated with an eventive passive would imply the existence of measurable computational cost movement, which would be responsible for the difficulty children have on verbal passives. The absence of the relevant type of movement in adjectival passive constructions with copular characteristics would explain why children are initially capable of dealing with short agentive passives. We assume that, in Portuguese, children do not attend to the differences auxiliary selection implies in the target grammar. Three psycholinguistic experiments were conducted, in order to investigate the hypotheses proposed. The first two experiments show some difficulty on every verbal passive in Portuguese (except for short agentive passives) and highlight the relevance of aspectual and semantic features allowing a simpler derivation to be licensed in the logical form. The last experiment evaluated children´s ability to distinguish the different auxiliaries involved on the derivation of short passive sentences. The results are compatible with the hypotheses and suggest that children would take adjectival constructions into account in achieving full acquisition of verbal passives.