Most electromagnetic interference standards specify that measurements of radiated emissions must be performed in the far field (FF), e.g. at an open-area test site or in a semi-anechoic chamber. Since near field (NF) measurements are cheaper, quicker and more flexible compared to FF tests, establishing a correlation between NF and FF data is of great research interest. One strategy to achieve this goal is to find a set of basic radiators comprising electric and magnetic dipoles that generate the same NF as the original source at selected observation points. This set of dipoles, based on the uniqueness theorem, can then be used to predict the FF radiation patterns. The uniqueness theorem requires that electric or magnetic fields are matched on a closed surface with respect to the magnitude and phase. The focus of this thesis is the investigation of FF prediction based on NF magnitude-only data. In this thesis, a robust NF-FF conversion model based on Genetic Algorithms (GAs) is built up to predict the radiation of printed circuit boards (PCBs). This is done by introducing a dipole moment magnitude range pre-selection before the initialisation step of GAs, customising the processes of selection, crossover and mutation for anti-sticking and checking the correlation between NF and FF fitness values. Since the performance of GAs is tightly related to the number of dipoles in the GA model, FF characteristics of generic radiation sources (such as a long wire and a large loop) are analysed using both analytical calculation and source modelling by GAs. For structures with simple FF patterns, if more dipoles than necessary are used, the computational cost of GAs is unnecessarily high. On the other side, for structures with complicated FF patterns, the GA modelling may not be able to well approximate the FF radiation, due to the limitation for GAs to tackle too many unknowns. Therefore the scope of the model applicability is discussed, and a dipole number N, depending on the electrical size of the source, is recommended for GA modelling. By applying GAs to get the equivalent dipole set of a radiating PCB from the magnetic NF magnitudes, NF sampling approaches are investigated in detail, including where to locate NF sampling planes, what plane coverage angle to choose, how many points to observe, what type of data to collect, what dynamic range to allow for the data, and how many planes to choose. Two case studies are presented for predicting the FF radiation of PCBs from magnetic NF magnitude-only observations, and validate the NF sampling approaches in this thesis.

Thesis (Ph. D.)--Indiana University of Pennsylvania. / Includes bibliographical references.

Abstrakt Fysisk aktivitet på recept (FaR), är en metod som används för att förebygga och behandla folksjukdomar. Syftet med FaR är att få individer att bli mer fysiskt aktiva [FA] och därigenom påverka sjukdomsbesvären i en positiv riktning. Till denna förändring krävs motivation och någonting som skapar en vilja att utföra FA. Syftet med denna studie har därför varit att undersöka om ett FaR- recept kan motivera till ökad FA hos FaR-klienter. Den metod som användes var semistrukturerade intervjuer med öppna frågor. Sex respondenter deltog i studien. Kravet var att personerna skulle ha FaR-recept. Resultatet pekar på att det upplevda stödet från såväl sjukvården, FaR- ledaren samt den sociala delen i form av familj, vänner och bekanta spelar stor roll för skapandet och upprätthållandet av motivation till FA hos FaR- klienten. Slutsatsen är att genom förmedlad kunskap och stöd från sjukvården och FaR- ledaren skapas en meningsfullhet, förståelse och hanterbarhet hos klienten. Detta kan leda till att öka motivationen till FA hos FaR-klienten. / Abstract Physical activity on prescription, (PaP), is a method used to prevent and treat common diseases. The aim of PaP is to get individuals to become more physically active [PA] and through that influence the disorders in a positive direction through a more active lifestyle. This change requires motivation and something that creates a desire to perform the PA. The purpose of this study was therefore to investigate whether a prescriptions may warrant increased PA in the clients. The methodology used in this study was semi-structured interviews with open questions. Six respondents participated. The requirement was that the people would have a PaP- prescription. The results indicate that the perceived support from both the healthcare, PaP- leader and social support plays a major role in the creation and maintenance of motivation to the PA in the PaP- client. The conclusion is that the mediated knowledge and support from health care and PaP leader created a meaningfulness, understanding and manageability of the client. This can lead to increased motivation to PA in PaP client.

Les débitages de lamelles obtenues par pression apparaissent il y a environ 20 000 ans en Asie du nord-est et leur diffusion est attestée aussi bien vers l’Asie centrale que vers l’Alaska et la Colombie-Britannique en passant par la Sibérie. Cette recherche analyse ainsi la progression de ces industries depuis l’Extrême-Orient vers l’Amérique du Nord : de nombreuses séries en provenance du Primorye, de la Sibérie et du nord-ouest de l’Amérique du Nord font l’objet d’une étude typo-technologique rigoureuse. La facile reconnaissance des industries à composante lamellaire permet d’étudier l’évolution, à une large échelle géographique et chronologique, du système techno-économique du peuplement initial du Nouveau Monde, tout en restant sur des contextes technologiquement comparables. La singularité de ce travail repose non seulement dans le choix du sujet mais aussi dans la méthodologie employée, c’est-à-dire l’application de la technologie lithique développée par l’école française à l’étude des industries paléolithiques à composante lamellaire et à certaines problématiques concernant le premier peuplement du Nouveau Monde. De nombreuses questions seront abordées : quelle est l’origine géographique et chronologique des premiers débitages lamellaires par pression ? Pouvons-nous mettre en évidence certains facteurs déclencheurs ? Comment sont employées les lamelles ? Quels éléments expliquent la variabilité des méthodes de débitages ? Sommes-nous face à un phénomène de diffusion d’une idée ou de migration de population ? Observe-t-on certaines voies migratoires préférentielles ? L’outillage associé est-il constant ou très variable ? Comment la technologie lithique permet-elle de mettre en évidence certaines zones d’interaction ? L’approche inédite développée ici permet d’aborder ces thématiques sous un angle parti culier et d’abouti r à des résultats, à des visions et à des propositions sensiblement différents de ce qui a été avancé à ce jour. / Débitage of pressure microblades appeared in the archaeological record about 20,000 years ago in Northeast Asia, followed by their diffusion toward Central Asia as well as toward Siberia, Alaska, and British Columbia. This research analyzes the spread of these microblade industries from the Asian Far East to North America, utilizing many archaeological collections from Primorye, Siberia, and northwest North America as the basis of a meticulous typo-technological study. The easy recognition of microblade-bearing sites allows studying the evolution, on a wide geographical and chronological scale, of the technoeconomic system during the initial peopling of the New World, while retaining technologically comparable backgrounds. The singularity of this work lies not only in the chosen subject but also in the chosen methodology, i.e., the application of lithic technology as developed by the French school to the study of Palaeolithic industries with microblade components, as well as to some issues concerning the first peopling of the New World. Many questions will be discussed, including: What is the geographical and chronological origin of the first pressure microblade industries? Can we highlight some factors that stimulated such an invention? How were microblades used? What elements can explain the variability of the débitage-producing methods? Is the progression of microblade industries the result of a technological diffusion or a human migration? Can any preferential migratory routes be identified? Is the associated toolkit highly variable or is it relatively constant? How does the analysis of lithic technology allow the assessment of interactions between groups? The new approach developed here addresses the issues from a different angle and leads to new visions, proposals, and results that are noticeably different from those that have been suggested to date.

No description available.

Notre étude se propose d’analyser les enjeux et les formes de la représentation de la figure de l’auteur dans le roman vietnamien francophone dans la première moitié du XXe siècle, roman dont les thématiques sont liées au contexte colonial. Cette figure est l’image que l’auteur veut donner de lui-même dans son discours, une manière de se définir et de se positionner dans les confrontations culturelles entre l’Occident et l’Extrême-Orient. La colonisation française apporte à l’espace culturel vietnamien une nouvelle vision qui est fondamentalement différente de la culture et des représentations extrême-orientales. Dans ce contexte de coexistence des cultures, certains écrivains vietnamiens choissisent le français pour exprimer leurs problèmes identitaires résultant du métissage culturel, de leur situation paradoxale d’être à la fois colonisé indigène et médiateur francophile. Ils tendent à se présenter dans leurs œuvres à travers l’expression d’une multitude de nuances entre deux attitudes opposées envers l’altérité dans la société vietnamienne coloniale : d’un côté la fascination de l’Occident de la part des jeunes intellectuels modernistes ; de l’autre, le rejet de l’Occident de la part des conservateurs confucéens. Un engouement excessif s’oppose alors à une attitude d’hésitation non dénuée d’ambiguïtés à l’égard de l’occupant, et à des tentatives pour concilier les deux cultures. Nous analyserons les figures discursives de l’auteur, en tant que sujet multiculturel, dans douze romans (de 1921 à 1964) représentatifs de l’ensemble de la production romanesque de langue française de l’époque coloniale jusqu’à la fin du XXe siècle. / Our goal in this study is to consider the ways in which authors of Vietnamese francophone novels of the early twentieth century that dealt with themes related to the colonial context chose to represent themselves in their novels. We will look at the image that the author seeks to project of himself, how he defines and places himself within the cultural confrontations between the West and the Far East and what the stakes of that representation were. French colonization brought to the Vietnamese cultural landscape a new vision that was fundamentally different from the culture and the cultural representations of the Far East. In the context in which these two cultures coexisted, certain Vietnamese writers chose French as the language with which to express the problems of identity that resulted from this cultural hybridization and of the paradox of their position within it, in which they were simultaneously colonized natives and cultural mediators. They tended to present themselves in their works by expressing the multitudinous nuances contained in the opposing attitudes to otherness in Vietnamese colonial society: On the one hand the fascination that the West holds for the younger generation of intellectuals; On the other, the rejection of the West on the part of the Confucian conservatives. Excessive enthusiasm is tempered by an attitude of hesitation fraught with ambiguity regarding the colonizer and efforts to reconcile the two cultures. We will analyze the malleable identities of the author as a multicultural subject in twelve novels (from 1921 to 1964) that are representative of the entirety of the novels written in the French language from the colonial period until the end of the twentieth century.

In this thesis, I have developed a range of theoretical and numerical techniques for modelling the behaviour of partially coherent optical systems and multi-mode detectors. The numerical simulations were carried out for the ultra-low-noise Transition Edge Sensors (TESs) being proposed for use on the SAFARI instrument on the cooled aperture infrared space telescope SPICA (34 - 210 μm). The optical behaviour of the SAFARI system is described in terms of the optical modes of the telescope, as distinct from the optical modes of the detector. The performance of the TESs were assessed in terms of signal power, background power and photon noise. To establish a method for precisely characterising and calibrating ultra-low-noise TESs, a cryogenic test system was designed and engineered to measure the optical efficiencies of the SAFARI TESs. The multi-mode, partially coherent illumination conditions of the measurement system were engineered to be precisely the same as those of the telescope. A major difference between the test system and the telescope’s optics is that the telescope will have focusing elements, but the test system was designed to avoid focusing elements in order to keep the optical path as clean as possible. The theoretical formalism and numerical models were adapted accordingly to address this difference. The numerical simulations show that the test system could provide near identical optical performance as that of the telescope system even though the focusing elements were absent. I also performed experimental measurements to investigate the optical efficiencies of the multi-mode TESs. The detectors worked exceedingly well in all respects with satisfactory optical efficiencies. In addition, it has been shown that the optical model provides a good description of the optical behaviour of the test system and detectors. Further modal analysis was developed to study losses in the multi-mode horns. The optical behaviour of the waveguide-mounted thin absorbing films in the far-infrared was modelled using a mode-matching method.

L'écoulement de jeu est un phénomène très important dans les turbomachines. Il provient du mouvement relatif entre la pale et la paroi d'extrémité, et la différence de pression à travers la pale. L'écoulement de jeu est extrêmement complexe pour sa nature tridimensionnelle et instable, et son existence conduit à de nombreux effets défavorables, par exemple, les pertes de performance aérodynamique et les émissions de bruit. C'est pourquoi l'écoulement de jeu a motivé de nombreuses recherches expérimentales et numériques. Afin d'améliorer la compréhension du écoulement de jeu et le bruit de large bande associé, une campagne de recherche a été menée au LMFA. En ce qui concerne l'écoulement de jeu, cette campagne de recherche comprend une expérience avec des technologies de mesure avancées, un calcul zonal LES et une série de calculs RANS / URANS. L'expérience et les simulations considèrent une configuration simple de l'écoulement de jeu à un faible nombre de Mach. Les résultats expérimentaux et numériques sont analysés de façon systématique et approfondie dans la présente étude. Enfin, des efforts sont déployés pour la modélisation et la prédiction du bruit à large bande avec des résultats expérimentaux et numériques. On observe dans l'expérience un système à multiple-tourbillon, avec une tourbillon de jeu intense. Les différentes analyses sur les caractéristiques d'écoulement montrent un bon accord entre l'expérience et le ZLES dans la région du écoulement de jeu. L'approche zonale (RANS-LES) s'avère être un outil puissant pour fournir une description détaillée du écoulement de jeu, avec un coût de calcul limité. Cependant, les calculs RANS et URANS surestiment globalement la diffusion de la tourbillon. En outre, l'oscillation du tourbillon de jeu est étudiée en utilisant des champs instantanés de PIV et l'amplitude d'oscillation est évaluée. La réponse dynamique de la tourbillon de jeu est également étudiée avec URANS aux fréquences choisies. Deux modèles de prédiction du bruit en champ lointain, correspondant à deux sources acoustiques différentes, sont reformulés et mis en oeuvre avec les données de champ proche des simulations numériques. Ces prédictions sont comparées aux mesures à champ lointain. En utilisant les données ZLES, le modèle de l’écoulement de jeu sur-estime le bruit généré dans la région de jeu. Le modèle de bruit de bord de fuite est implémenté avec les données ZLES et les données RANS et fournit une très bonne prédiction dans une large bande de fréquence. / The tip-leakage flow is a common flow feature in turbomachines. It originates from the relative motion between the blade tip and the end-wall, and the pressure difference across the blade. The tip-leakage flow is extremely complex for its three-dimensional unsteady nature, and its existence leads to many unfavourable effects, such as aerodynamic performance losses and noise emissions. These issues have motivated extensive experimental and numerical researches from both aerodynamic and aeroacoustic points of view. In order to improve the understanding of the tip-leakage flow and its associated broadband noise, a research campaign has been carried out at LMFA. Regarding the tip-leakage flow, this research campaign includes an experiment with advanced measurement technologies, a zonal LES computation and a series of RANS/URANS computations. Both the experiment and the simulations consider a single-airfoil configuration at low Mach number. Experimental and numerical results are analysed systematically and thoroughly in the current study. Finally, efforts are put on the broadband noise modelling and prediction based on the experimental and numerical results. A multi-vortex system with an intense tip-leakage vortex is observed in the experiment. The various analyses of the flow characteristics show a good agreement between the experiment and the ZLES in the blade tip region. The zonal (RANS-LES) approach proves itself to be a powerful tool to provide a detailed description of the tip-leakage flow, with a limited computational cost. However, the RANS and URANS computations globally over-estimate the diffusion of the tip-leakage vortex. Furthermore, the random oscillation of the tip-leakage vortex is investigated using PIV instantaneous flow fields and the wandering amplitude is evaluated. The dynamic response of the tip-leakage vortex is also studied with URANS at selected frequencies. Two far-field noise prediction models, corresponding to two different acoustic sources, are reformulated and implemented with the near-field data from the numerical simulations. These predictions are compared to the far-field measurements. Using the ZLES data as input, the blade-tip self-noise model is found to over-estimate the noise generated in the blade-tip region. The trailing-edge noise model is implemented with the time-averaged ZLES and the RANS near-field data, and yields a very good prediction within a broad range of frequency.

Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro / Inselbergs são afloramentos rochosos isolados que emergem abruptamente acima das planícies que os circundam, formados principalmente por afloramentos de rochas graníticas e gnáissicas. São lugares com alta diversidade e endemismo, e caracterizados por alto grau de insolação, temperaturas do ar e do solo, com ventos fortes e solos com baixa retenção de água. Sementes de três espécies típicas dos inselbergs (Alcantarea glaziouana, Barbacenia purpurea e Tibouchina corymbosa) foram estudadas para avaliar o efeito das temperaturas constantes (15 a 40C) e alternada (20-30C), o estresse hídrico (Ψw = 0,0 a -1,2 MPa) promovido por soluções de polietileno glicol 6000 (PEG) e a qualidade da luz sob diferente valores de razão vermelho: vermelho extremo (V:VE), na porcentagem final e velocidade de germinação. Os resultados mostraram que todas as espécies têm sementes muito leves, variando entre 0,005 - 0,04 g. As três espécies apresentaram alta germinação sob temperaturas entre 20C e 30C, e não germinaram a 40C, exceto A. glaziouana. A máxima germinação foi obtida em água destilada (0 MPa) e as diferentes condições de estresse hídrico reduziram a percentagem e a velocidade de germinação de todas as espécies estudadas. A. glaziouana foi a espécie menos sensível a redução do potencial hídrico. As sementes de todas as espécies necessitam de exposição a luz para a máxima germinação (fotoblásticas positivas) e a porcentagem final de germinação foi inibida sob baixos valores de V:VE. A razão V:VE que resultou em 50% da máxima germinação variou entre as espécies. Estes resultados demonstram que a germinação pode limitar a capacidade das espécies em colonizar tanto novas áreas como área perturbadas, além de contribuir para a distribuição das espécies nos inselbergs. / Inselbergs are isolated rock outcrops that rise abruptly above the surrounding plains, mainly formed by outcrops of granitic and gneissic rocks. They are places with high diversity and endemism, and are characterized by high degree of insolation, air temperatures and soil, with high winds and soils with low water retention. Seeds of three typical inselberg taxa (Alcantarea glaziouana, Barbacenia purpurea and Tibouchina corymbosa) were studied to evaluate the effect of constant (15 to 40C) and alternating (20-30C) temperatures, water stress (Ψw = 0.0 to -1.2MPa) promoted by solutions of polyethylene glycol 6000 (PEG) and light quality under different red:far red (R:FR) ratios on the percentage and germination rate. The results showed that all species have very light seeds, ranging from 0.005 to 0.04 g. All species presented high germination under temperatures between 20C and 30C, and did not germinate under 40C, except A. glaziouana. Maximum germination was obtained in distilled water (0 MPa) and water stressed conditions reduced the percentage and rate of germination in all species studied; A. glaziouana was less sensitive to low water potentials. Seeds of all species required light for maximum germination (photoblastic positive) and the final germination percentage was inhibited at low R:FR ratios. The R:FR value that resulted in 50% of maximum germination varied among species. These results show that germination can limit the ability of species to colonize newly and disturbed habitats and also contributes to inselbergspecies distribution.

Pour répondre aux questions que pose la faisabilité d’un dispositif de détection d’explosifsà l’aide de la technologie de spectroscopie térahertz, cette thèse a exploré troisaxes. Le premier a consisté à établir une base de données des signatures spectrales (indiceet absorption) d’une large gamme de matériaux d’intérêt pour ce type d’applications,à partir des données expérimentales que nous avons mesurées par spectroscopie dans ledomaine temporel. Nous avons identifié les matériaux montrant une signature spectralesignificative et nous avons aussi étudié l’effet des matériaux de dissimulation.Dans la seconde partie de ce travail, nous avons conçu et construit un banc de spectroscopieultra-large bande destiné à une meilleure identification spectrale des substances. Nousavons identifié les limites techniques de ce type de banc et donné les pistes pour atteindreles performances désirées.Ensuite, nous avons développé et validé un banc de spectroscopie en réflexion, de typegoniométrique, afin de détecter des signaux térahertz diffusés par des matériaux hétérogènes.Finalement, nous avons étudié les plasmons de surface dans le domaine térahertz, en vuede la détection de très faibles quantités de matière. / This PhD work was performed in view of using terahertz electromagnetic signals forthe detection and identification of dangerous and prohibited substances. In a first stage,a database of the terahertz properties (namely refractive index and absorption) of thesesubstances was created from the measurements we performed using terahertz time-domainspectroscopy. Then a large bandwidth terahertz time-domain set up has been built, togetherwith a goniometric-type set up that allows us recording signals scattered by roughor heterogeneous samples. Finally, we studied the excitation and propagation of surfaceplasmons in the terahertz domain, which may be used for the detection of small amountsof matter.