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1
Moyrand, Alain. "Travaux multiples de droit public." Lille 3 : ANRT, 1989. http://catalogue.bnf.fr/ark:/12148/cb37610987z.
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Moyrand, Alain. "Travaux multiples de droit public." Rouen, 1987. http://www.theses.fr/1987ROUEL038.
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La répression des fautes commises par les étudiants est juridictionnalisée. Chaque université possède une section disciplinaire qui est une juridiction administrative de première instance, composée paritairement d'enseignants et d'étudiants. Les principaux apports de cette étude concernent la définition des règles de compétence matérielle et territoriale; les franchises universitaires et le partage du pouvoir d'annulation des examens en cas de fraudes, entre les jurys d'examens et les juridictions universitaires. D'autre part, ce travail analyse la totalité des arrêts rendus par le C. S. E. N. Concernant les étudiants et la totalité des jugements rendus par la section disciplinaire du conseil de l'université de Rouen. 2 L'étude de la participation des étudiants aux élections universitaires met en évidence un taux d'abstention très élevé. L'analyse socio-politique de ce phénomène révèle que la "non-participation" s'explique essentiellement par un facteur social, à savoir : la faible intégration des étudiants aux structures universitaires. Au surplus cette étude fait apparaitre que la communauté étudiante ne constitue pas un groupe "caractérise" (c'est-à-dire sépare du groupe social global) et autodétermine en fonction de sa condition liée aux études. 3 - Etude de la juridiction administrative tchadienne de l'indépendance à nos jours et des causes de son non fonctionnement. 4 - Analyse de la légalité d'exception au Tchad depuis l'indépendenceThe repression of faults committed by students depends on juris- dictions. Every university has its own disciplinary section which is an administrative jurisdiction of inferior instance and is equally represented by teachers and students. This study is an analysis of the whole lot of judgments delivered by the C. S. E. N. Concerning students and the totality of judgments delivered by the disciplinary section of the council of the University of Rouen. 2 - The study of the universitary elections shows that students do not take share in the vote. The socio-political analysis of this attitude reveals that this way of acting clears up by a social factor which is the weak integration of students within their university. 3 - Study of the administrative jurisdiction of Tchad from independence to nowadays and the causes of its non-functioning. 4 - Analysis of the legality of exception in Tchad since independence
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Girard, Jean-François. "Imagerie géoradar et modélisation des diffractions multiples." Université Louis Pasteur (Strasbourg) (1971-2008), 2002. https://publication-theses.unistra.fr/public/theses_doctorat/2002/GIRARD_Jean-Francois_2002.pdf.
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Le géoradar est une technique couramment utilisée pour prospecter le proche sous-sol. Des ondes électromagnétiques à hautes fréquences (>10 MHz) sont émises dans le sol et les échos enregistrés traduisent les contrastes de permittivité diélectrique entre les différents milieux. Cela permet d'imager les changements de lithologie, des états de fracturation différents, des variations de teneur en eau Dans ces milieux diélectriques, l'onde perturbe les distributions de charges électriques liées et induit une polarisation qui à son tour influe sur l'onde et déforme le signal. En accord avec les mesures sur échantillons, nous utilisons une loi puissance de la susceptibilité électrique en fonction de la fréquence pour caractériser cette dispersion. Avec une telle sensibilité aux différents matériaux et une résolution allant de quelques centimètres à plusieurs décimètres, le traitement des données requiert la prise en compte de la forte hétérogénéité des milieux étudiés. C'est pourquoi nous avons développé un algorithme de modélisation par différences finies en domaine temporel et généralisé l'emploi d'une convolution récursive pour les milieux dispersifs. Nous avons également implémenté d'une façon originale des conditions limites de type " perfect match layer ". L'analyse des coefficients de réflexion nous a permis de valider l'hypothèse qu'une faible variation de la teneur en eau pouvait expliquer la présence des réflecteurs à l'intérieur d'une dune de sable. Nous avons aussi exploité le contenu fréquentiel des signaux en calculant les rapports spectraux entre des signaux réfléchis à différents offsets pour estimer la permittivité diélectrique. Ces valeurs des paramètres et la prise en compte des variations de la teneur en eau servent ensuite à modéliser des situations réalistes. En dernier lieu, nous avons utilisé avec succès le même code de différences finies, en renversant le temps, pour rétro-propager le champ enregistréGround Penetrating Radar is widely used to prospect the near surface with high frequency electromagnetic waves (F> 10 MHz). Imaging the dielectric contrasts in the first meters of the earth shows the changes in lithology, fracturation, or water content In these dielectric media the electric field induces a polarisation, which results in the distortion of the signal. Following precedent studies, we use a frequency power law for the electric susceptibility to model this dispersion effect. With such a sensibility to the different media and a resolution ranging from 5 centimeters to several decimeters, the strong heterogeneity of the near surface needs to be considered for an efficient data processing. For this reason, we developed a new modeling algorithm using the finite difference time domain scheme and proposed a modified recursive convolution scheme to include all type of dispersive properties. As boundary conditions, we implemented absorbing perfect match layers in an original way. We also studied the reflexion coefficients inside aeolian sand dunes and concluded that they can be explained by small variations in the water content. The analysis of the spectral ratio between signals at different offsets provides us with a new tool to estimate the dielectric permittivity. These data allow us to model more realistic synthetic cases. At last, we successfully used the same modeling program, but with time reversal, to propagate the recorded fields back to the source
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Bersweiler, Daniel. "L'enfant et le temps, au carrefour d'enjeux multiples." Nancy 2, 2005. http://docnum.univ-lorraine.fr/public/NANCY2/doc245/2005NAN21021_1.pdf.
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Dans ce travail de thèse, l'auteur a envisagé les différents rapports que l'enfant est amené à tisser avec le temps, distingué de quelle manière il peut construire un rapport personnel au temps, précisé de quels outils il dispose, ou desquels il peut se saisir dans ce but. L'auteur a mené son travail dans trois directions principales : - Une investigation documentaire en philosophie, sociologie et histoire a permis de rappeler les approches sociales du temps. - La prise en compte de travaux de recherche, de témoignages et de textes réglementaires a permis de préciser les caractéristiques du temps de l'enseignement, et de distinguer les enjeux des dispositifs d'aménagement des rythmes de vie de l'enfant. - La saisie de documents issus de la pratique de classe, et d'interviews réalisées auprès d'enfants a permis de révéler des processus de compréhension et de représentation du temps élaborés par l'enfant lui-même. Ces démarches complémentaires ont abouti à l'identification d'enjeux s'attachant au rapport au temps et à la production d'un paradigme du rapport de l'enfant au temps, proposé comme outil d'observation, d'action et de formationIn this Master's thesis, the author has considered the different relations children will have to experience with the notion of time, told how children can built a personal link to it, explained what specific tools already are, or might become aviable to them in that purpose. The author has organised his work looking at three different main directions : - a documentary inquiry in philosophy, sociology and history, has made it possible to consider the social approaches to time, - a survey of different pieces or research, of testimonies and of regulations writings has made clear the characteristics of the problems raised by the devices set up to improve the rhythm of the children's daylife, - the use of documents illustrating teaching skills, and of interviews of children, has made it possible to identify processes in the understanding and the appropriation of the idea of time by the children themselves. These supplementary procedures have led to the identification of issues linked to time, and to the production of a paradigm of the relation linking children to time, suggesting as a tool for survey, action and training as well
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Mayot, Estelle. "Monobactames et triazoles fluorocarbonés amphiphiles : vers des systèmes catanioniques à propriétés multiples." Nancy 1, 2007. http://docnum.univ-lorraine.fr/public/SCD_T_2007_0136_MAYOT.pdf.
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Les travaux présentés dans ce mémoire sont consacrés à la conception et à l’étude de nouveaux systèmes catanioniques bioactifs originaux, formés à partir de deux tensioactifs de charges opposées, apportant chacun une propriété biologique spécifique complémentaire de l’autre, susceptible d’engendrer une synergie. Dans un premier temps, sur la base de travaux antérieurs, nous avons réalisé la synthèse de monobactames amphiphiles ionisables présentant une HLB facilement modulable par greffage d’un motif polyéthoxylé. Les propriétés physico-chimiques particulières des tensioactifs fluorocarbonés nous ont incités à synthétiser des composés de type b-aminoacides perfluorés, précurseurs de cycles lactames. Dans un deuxième temps, nous avons étudié la synthèse de divers triazoles, porteurs également d’une chaîne perfluorée, par le biais d’une cycloaddition 1,3 dipolaire ou d’une cyclisation intramoléculaire. Les études physico-chimiques de chacun des tensioactifs parents, notamment par mesure de la tension superficielle, ont révélé une grande activité de surface pour tous les composés. Une série de systèmes catanioniques a ensuite été préparé en associant deux amphiphiles par interaction ionique, et plus particulièrement un dérivé de type triazole et un de type monobactame. La mesure de leur capacité tensioactive a montré d’intéressants phénomènes de synergie. Une étude préliminaire de leurs propriétés antibactériennes a donné des résultats encourageants. Enfin, le fort potentiel des amphiphiles fluorés nous a conduit à nous intéresser à d’autres structures fluorocarbonées, dérivées d’a-aminoacides et d’imines, qui pourront par la suite être engagées dans un système catanioniqueIn the work presented in this thesis, we were interested in the conception and in the study of original catanionic systems, constituted by ionic interaction between two surfactants with opposed charges, each one bringing a specific biological property. Firstly, we synthesised different amphiphilic ionisable monobactams, with an easily flexible HLB by addition of a polyoxyethylene part. Particular physico-chemical properties of highly fluorinated surfactants led us to synthesised perfluorinated b-aminoacid, which are precursors of lactams cycles. Secondly, we studied the synthesis of different 1,2,3-triazoles, also with a perfluorinated chain, via a 1,3 dipolar cycloaddition or an intramolecular cyclisation. The physico-chemical studies of each parent surfactant, notably by the measure of the surface tension, revealed a high tensioactive power for every compound. Different catanionic systems were prepared afterwards by associating two surfactants with opposed charges, particularly a triazole and a monobactam. The measure of their tensioactive activity showed interesting synergistic effects. A preliminary study of their antibacterial properties gave promising results. Eventually, the high potential of fluorinated amphiphiles led us to the interest of other perfluorinated structures, some a-aminoacids and some imines, which could be engaged in a catanionic system study at a later date
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Raouj, Abdelaziz. "Sur la densité de certains ensembles de multiples : résolution d'une conjecture d'Erdös." Nancy 1, 1992. http://docnum.univ-lorraine.fr/public/SCD_T_1992_0120_RAOUJ.pdf.
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Erdös a conjecturé que, lorsque l'entier n parcourt une suite convenable de densité unité presque chaque entier M possède un diviseur proche d'un diviseur de N. Nous résolvons cette conjecture sous une forme quantitative et plus générale, en évaluant asymptotiquement la densité de certains ensembles de multiples définis a partir de l'ensemble des diviseurs de N. Les démonstrations reposent sur la technique de Maier et Tenenbaum, et sur des calculs de moyennes pondérées, étayées par des raisonnements combinatoires. Certaines propriétés de nature probabiliste sont établies par des méthodes d'analyse harmonique.
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Brushwood, James Darrach. "Peer Accounting Information and the Use of Peer-based Multiples for IPO Valuation." Diss., The University of Arizona, 2015. http://hdl.handle.net/10150/556239.
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Initial public offerings (IPOs) are primarily valued using the comparable firms approach, whereby underwriters rely heavily on multiples based on the accounting information of peer firms. Effective use of the comparable firms approach depends significantly on the underwriter's ability to estimate the expected future growth and profitability of the IPO firm and its peers and make appropriate adjustments to the multiples to arrive at a final offer price for the IPO shares. I find evidence that, in general, IPO valuations are decreasing relative to peers in the similarity of the peer group to the IPO firm, but this effect is moderated by the peer group's accruals quality. These findings suggest that when peers are similar to the IPO firm, underwriters make less adjustments to the final offer price, however, higher peer accruals quality may ease the assessment of differences in growth and profitability, facilitating further adjustments.
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Souza, Vanessa Aparecida de. "A "ambigüidade institucional" no conselho deliberativo de fundo de amparo ao trabalhador (1990-2002): avanços e recuos." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2007. http://hdl.handle.net/10183/13104.
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L´objectif générale de cette étude consistait d´analyser la présence et/ou l´absence de groupes sociaux et d´institutions représentatives visant à formuler et/ou intervenir dans les politiques publiques du travail qui traitent les femmes, les noirs, les personnes avec des incapacités, les travailleurs avec plus de 40 ans (publics multiples), dans le CODEFAT (Conseil Délibératif du Fond d´Assistance au Travailleur). Ces publics étaient choisis en raison d´être les plus vulnerables à l´entrée du marché du travail et peuvent être conçus comme une des principales cibles dans la formulation de politiques publiques. La période analysée s´étendait de 1990 à 2002, de la formation jusqu´à la fin du second gouvernement de Fernando Henrique Cardoso. Dans ce contexte, prenant comme point de repère le processus décisoire tout au long de douze ans, on a analysé si le Conseil peut être considéré comme ´´une sphère publique forte´´ en termes théoriques et empiriques, s´il est délibératif, partiel ou tripartiel et s´íl maintient la capacité normative de formuler les politiques publiques d´une manière autonome, au moins, du point de vue formal. Dans cette façon, la question principale était la suivante : le Conseil était-il perméable à la présence et à la représentation des publics multiples dans le processus de la formation de politiques publiques ? On a employé comme base en premier lieu, la théorie de Nancy Fraser qui a réalisé une relecture de la conception de la sphère publique à Habermas, privilégiant une analyse des groupes socialement vulnerables. Il est également convenu d´étudier le fonctionnement du Conseil, l´existence ou inexistence d´autonomie dans son rapport avec l´Executif, vu qu´on a formulé le concept d´ambiguité institutionale à partir du cas en question et d´une revision de la littérature, comme un possible modèle explicatif du fonctionnement de la sphère publique au Brésil.objetivo geral da pesquisa foi analisar a presença e/ou ausência de grupos sociais e instituições representativas que buscaram formular e/ou intervieram nas políticas públicas de trabalho que tratavam das mulheres, negros, pessoas com deficiência e trabalhadores com mais de 40 anos de idade (múltiplos públicos), no Conselho Deliberativo de Fundo de Amparo ao Trabalhador (CODEFAT). Estes públicos foram escolhidos por serem os mais vulneráveis ao ingresso no mercado de trabalho e poderiam se constituir como um dos principais focos na formulação de políticas públicas. O período analisado foi entre 1990 e 2002, compreendendo seu momento de formação até o término do segundo governo de Fernando Henrique Cardoso. Nesse contexto, analisamos, a partir do processo decisório ao longo de doze anos, se o Conselho pode ser compreendido como "esfera pública forte" em termos teóricos e empíricos, por ser deliberativo, ser paritário, tripartite e ter poder normativo para formular políticas públicas autonomamente, ao menos do ponto de vista formal. Assim, a principal questão foi perceber se o Conselho foi permeável à presença e representação dos múltiplos públicos no processo de formulação de políticas públicas, utilizando como base, especialmente, a teoria de Nancy Fraser, que realizou uma releitura da concepção de esfera pública em Habermas e privilegiou a análise de grupos socialmente vulneráveis. Coube também analisar o funcionamento do Conselho, captando a existência ou não de autonomia em relação ao Executivo, sendo que a partir do caso analisado e da revisão da literatura, apresentamos o conceito de "ambigüidade institucional" como uma proposta de modelo explicativo do funcionamento de esferas públicas no Brasil.
The general objective of this research was to analyze the presence and/or representative absence of social groups and institutions that tried to formulate and/or intervened in the public politics of work that dealt with women, black people, handicapped people and workers of 40 years old and over (multiple public), at the Deliberative Body of Fundo de Amparo do Trabalhador (CODEFAT) - Worker’s Supporting Fund. These groups were chosen for being the most vulnerable to enter the job market and could be considered as being the main focus in the shaping of public policy. The period under analysis was between 1990 and 2002, comprising the beginning until the end of Fernando Henrique Cardoso government. In this context, the decision-making spreading twelve years was analized, in addition to weather the council can be considered as "strong public sphere" in theoretical and empirical terms, as b eing deliberative, as be equal, tripartite and as having normative power when autonomously formulating public policy, at least in the formal point of view. Thus, the main question was to analyze weather the council was permeable to the presence and representation of the multiple publics in the process of formulation of public policy, using as a base, especially, the theory of Nancy Fraser, who carried through a new conception of public sphere in Habermas and privileged the socially vulnerable group analysis. It was also possible to analyze the functioning of the council, observing the existence or inexistence of autonomy in relation to the Executive, based in the case in hand and the revision of literature, we presented the concept of "institutional ambiguity", as a proposal for a clarifying model of the functioning of public spheres in Brazil.
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CASOTTI, FELIPE PRETTI. "INITIAL PUBLIC OFFERING IN BRAZIL (2004-2006): A VALUATION APPROACH USING MULTIPLES AND COST OF EQUITY." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2007. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=11704@1.
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A precificação das ações emitidas em ofertas públicas
iniciais tem sido alvo
de estudos em diversos países. Abordando o conceito de
avaliação por múltiplos,
este trabalho busca verificar se as ações das empresas
estavam sub-avaliadas ou
super-avaliadas no momento das suas Ofertas Públicas
Iniciais (Initial Public
Offerings). Posteriormente, são determinados os custos de
capital próprio
adotados na emissão, verificando-se a diferença entre
betas
utilizados no modelo
CAPM, no momento da IPO, e os betas dos 12 meses após a
oferta inicial. Para
tal, foi utilizada uma amostra composta por empresas que
abriram capital entre
2004 e 2006. Observou-se que as ações não foram sub-
avaliadas, mesmo após
serem observados elevados retornos iniciais. No entanto,
não há evidências
estatísticas de que foram super-avaliadas. Por fim,
verificou-se que os betas de 12
meses são significativamente maiores do que os betas
utilizados no momento da
precificação. Como esperado, o modelo CAPM determinou
retornos abaixo dos
retornos ocorridos após a emissão.The pricing of assets issued in initial public offerings has been the subject of many studies in several countries. Using the concept of relative valuation, this study intends to verify if the shares of selected companies were undervalued or not at the time of their IPOs (Initial Public Offering). Later, the cost of equity is determined and betas used in the CAPM model, at the time of the IPO, and the betas verified 12 months after the initial issue are compared. The sample is composed of companies with IPOs during the period 2004-2006. The results show that the shares were undervalued, although high initial returns were observed. However, there is no statistical evidence that they are overvalued. Finally, it was found that the betas after 12 months are significantly higher than the ones used at the time of the pricing. As expected, the CAPM model determined returns below the returns that occurred.
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Montavont, Nicolas. "Gestion optimisée d'interfaces multiples et prise en compte des déplacements rapides sur un terminal IPv6 mobile." Université Louis Pasteur (Strasbourg) (1971-2008), 2004. https://publication-theses.unistra.fr/public/theses_doctorat/2004/MONTAVONT_Nicolas_2004.pdf.
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Verger, Solange. "Les chemins multiples de la coopération transfrontalière franco-belge : analyse des dynamiques institutionnelles." Phd thesis, Université de Grenoble, 2011. http://tel.archives-ouvertes.fr/tel-00649238.
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La recherche doctorale porte sur le développement de la coopération transfrontalière entre collectivités territoriales de part et d'autre de la frontière franco-belge autour des villes de Lille, Tournai et Kortrijk. Au-delà d'une interrogation sur les facteurs externes et les usages politiques de ce nouveau domaine d'action publique, cette monographie étudie le processus de construction institutionnelle à l'œuvre au sein de cet espace émergent de coopération de la fin des années 1980 à 2010. Cela passe tout d'abord par l'analyse des mécanismes de légitimation, en particulier la construction de la question transfrontalière franco-belge en tant que problème légitime d'action publique ainsi que la " fonctionnalisation " de la COPIT (Conférence permanente intercommunale transfrontalière), une des principales organisations transfrontalières franco-belges de la zone étudiée. Les approches en termes de néo-institutionnalisme historique et les travaux relatifs à l'analyse des organisations permettent ensuite d'aborder l'institutionnalisation de la coopération transfrontalière sous l'angle de la production normative et de s'interroger sur la stabilisation dans le temps des règles produites. Le regard porte alors essentiellement sur la COPIT, qui devient en 2008 l'" Eurométropole Lille-Kortrijk-Tournai ", ainsi que sur les rapports de force entre les différents acteurs qui la composent, ce qui permet d'identifier les règles et valeurs partagées par ces acteurs et de comprendre leur construction à travers les représentations et les pratiques récurrentes des acteurs. Les mécanismes d'auto-renforcement des règles dans le cadre de l'organisation intercommunale transfrontalière apparaissant toutefois relativement faibles, l'analyse s'oriente finalement vers la mise en évidence d'ordres institutionnels à la fois concurrents et complémentaires à celui de la COPIT/Eurométropole : il s'agit de l'ordre institutionnel encadré par le dispositif européen INTERREG A et de la nébuleuse institutionnelle développée dans le cadre de diverses actions sectorielles. Au final, cette thèse montre la pluralité des logiques institutionnelles qui guident et caractérisent la coopération transfrontalière franco-belge ; autrement dit, la coexistence d'ordres institutionnels multiples pour un même phénomène.
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Bunce, Victor. "Does Growth Drive Valuation? An Analysis of Percent Revenue Growth as a Multiples-Based Valuation Method in Public Mergers and Acquisitions." Scholarship @ Claremont, 2018. http://scholarship.claremont.edu/cmc_theses/1980.
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Over the last twenty years, the worldwide number of public mergers and acquisitions has grown at a compound annual growth rate of 3.3%. In each transaction, acquirers and valuing parties including corporations, investment banks, and buyout funds value target firms using a variety of methodologies. This paper provides evidence in favor of trailing twelve months percent revenue growth as a multiple for valuation. Using the last twenty years of public mergers and acquisitions available on S&P’s Capital IQ, this paper finds that revenue growth is a consistently significant predictor of a target firm’s purchase multiple, measured as its enterprise value divided by revenue. Further, this paper finds no evidence that trailing twelve months percent revenue growth is more significant during economic bubbles, and that the effect is largely mitigated within the technology sector.
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Zelendová, Michaela. "Problematika oceňování start-upů." Master's thesis, Vysoká škola ekonomická v Praze, 2015. http://www.nusl.cz/ntk/nusl-205839.
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This thesis is dedicated to theoretical solutions and practical application of valuation methods used for evaluation of young startup companies. The aim of this work is to provide readers with theoretical introduction into the startup scene, conceivable valuation approaches and their practical application on the startup followed by drawing conclusions and recommendations. The thesis is divided into theoretical and practical part. The first part deals with the theoretical foundations of startups, the analysis of the Czech startup scene and possible arguments for valuing startups. The thesis discusses the specific characteristics of startups and their impact on the valuation process. The theoretical part is concluded by an analysis of the theoretical methods for the startup value estimation. In the practical section, selected valuation methods are applied on a particular startup company operating in the Czech Republic. Finally, the practical part summarizes the problems and specifics that arise during the valuation process followed by recommendations for valuation practice.
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Haught, Christopher M. "Enterprise Value/Monthly Active Users: A Valid Sector Specific Multiple for the Valuation of Social Media Firms?" Miami University / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=miami1500280724256454.
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Glenn, Dickins, and glenn dickins@dolby com. "Applications of Continuous Spatial Models in Multiple Antenna Signal Processing." The Australian National University. Research School of Information Sciences and Engineering, 2008. http://thesis.anu.edu.au./public/adt-ANU20080702.222814.
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This thesis covers the investigation and application of continuous spatial models for multiple antenna signal processing. The use of antenna arrays for advanced sensing and communications systems has been facilitated by the rapid increase in the capabilities of digital signal processing systems. The wireless communications channel will vary across space as different signal paths from the same source combine and interfere. This creates a level of spatial diversity that can be exploited to improve the robustness and overall capacity of the wireless channel. Conventional approaches to using spatial diversity have centered on smart, adaptive antennas and spatial beam forming. Recently, the more general theory of multiple input, multiple output (MIMO) systems has been developed to utilise the independent spatial communication modes offered in a scattering environment.¶
Underlying any multiple antenna system is the basic physics of electromagnetic wave propagation. Whilst a MIMO system may present a set of discrete inputs and outputs, each antenna element must interact with the underlying continuous spatial field. Since an electromagnetic disturbance will propagate through space, the field at different positions in the space will be interrelated. In this way, each position in the field cannot assume an arbitrary independent value and the nature of wave propagation places a constraint on the allowable complexity of a wave-field over space. To take advantage of this underlying physical constraint, it is necessary to have a model that incorporates the continuous nature of the spatial wave-field. ¶This thesis investigates continuous spatial models for the wave-field. The wave equation constraint is introduced by considering a natural basis expansion for the space of physically valid wave-fields. This approach demonstrates that a wave-field over a finite spatial region has an effective finite dimensionality. The optimal basis for representing such a field is dependent on the shape of the region of interest and the angular power distribution of the incident field. By applying the continuous spatial model to the problem of direction of arrival estimation, it is shown that the spatial region occupied by the receiver places a fundamental limit on the number and accuracy with which sources can be resolved. Continuous spatial models also provide a parsimonious representation for modelling the spatial communications channel independent of specific antenna array configurations. The continuous spatial model is also applied to consider limits to the problem of wireless source direction and range localisation.
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Umemoto, Karen Nora 1958. "You don't see what I see : multiple publics and public policy in a Los Angeles gang war." Thesis, Massachusetts Institute of Technology, 1998. http://hdl.handle.net/1721.1/9639.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Urban Studies and Planning, 1998.Includes bibliographical references (leaves 218-230).
An analytical concept of multiple publics is presented and applied to a case study of a gang conflict in Venice, California during 1993-1994. The concept of multiple publics is based on the assumption that individuals have many identities that vary in salience or relevance across situations. Publics represent groups based on the shared salience of identity group boundaries in a particular situation. Each public shares a unique interpretive lens through which they read events, actions and information. The composition and constellation of publics can change as situations change or are reframed. Over ten-month period, what was commonly referred to as a "gang war" broke out between two predominantly Latino gangs and one African-American gang. Seventeen people were killed and over 50 were injured. Of those killed, less than one-third were claimed as members the rival gangs in conflict. This gang-generated conflict led to racial tensions and polarization within the larger geographic neighborhood. An examination of the conflict through the lens of multiple publics reveals a series of shifts in the major line of cleavage over time-from persons to families to gangs to race and back to gangs. Shifts in the major line of cleavage represented changes in the relative salience of identity group boundaries among the many individuals involved or affected by the war. With each shift during its escalation, the intensity of conflict grew while the size of constituencies and publics were enlarged. Conversely, changing conditions and appeals to alternative identities led to shifts in salient group boundaries that opened opportunities for peace negotiations between two of the three gangs in conflict. The analysis of multiple publics in the case study shows four practices that may be useful in addressing similar conflicts. They are described as: 1) mapping multiple publics and multiple identities, 2) seeing from the lens of multiple publics, 3) reframing situations and opening dialogue, and 4) situationally identifying moral communities to which one is obliged.
by Karen Nora Umemoto.
Ph.D.
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Geering, Margo, and n/a. "Gender differences in multiple choice assessment." University of Canberra. Education, 1993. http://erl.canberra.edu.au./public/adt-AUC20050218.141005.
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Multiple choice testing has been introduced as an assessment instrument in almost all educational systems during the past twenty years. A growing body of research seems to indicate that tests structured to a multiple choice format favour males. In the ACT, Queensland and Western Australia, a
multiple choice examination known as ASAT was used to moderate student scores. Using data from the 1989 ASAT Paper 1, as well as data from the ACT Year 12 cohort of that year, an investigation was made of the items in the ASAT paper. This investigation attempted to identify specific types of questions that enabled males, on average, to perform better than females. Questions, which had a statistically significant difference between the results of males and
females, were examined further. An ASAT unit was given to students to complete and their answers to a questionnaire concerning the unit were taped and analysed.
The study found that males performed better, on average, than females on the 1989 ASAT Paper 1. The mean difference in the quantitative questions was much greater than in the verbal
questions. A number of factors appear to contribute to the difference in performance between males and females. A statistically significant number of females study Mathematics
at a lower level, which appears to contribute to females lower quantatitive scores. Females seem to be considerably more anxious about taking tests and this anxiety remains throughout
a multiple choice test. Females lack confidence in their ability to achieve in tests and are tentative about "risktaking" which is an element of multiple choice tests. The language of the test and male oriented content may contribute to females' negative performance in multiple choice testing.
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Healy, Christine, and Khealy@alphalink com au. "Multiple sclerosis and psychological well-being the role of physical and psychosocial factors." Swinburne University of Technology, 2005. http://adt.lib.swin.edu.au./public/adt-VSWT20051103.161133.
Full textAbstract:
Multiple sclerosis, (MS), presents affected individuals with an uncertain future, and has broad physical and psychosocial implications for their daily functioning. This study aimed to investigate the psychological well-being of people with MS with an emphasis on positive psychological functioning. It also aimed to extend previous research that suggested reporting perceived benefits during adversity may be indicative of cognitive adaptation. Disease-related variables (mobility, fatigue) and psychosocial factors (optimism, coping) were examined to ascertain the effects of living with MS upon well-being. Well-being was determined using two general measures (The Profile of Mood States (POMS), Shacham, 1983; and the Ryff Psychological Well-being Scale (PWB), Ryff & Keyes, 1995), and Mohr et al.�s (1999) MS psychosocial factors (Demoralization, Deteriorated Relationships, Benefit Finding). Participants were 154 people with MS who were recruited through the MS Societies of Victoria and Tasmania. Results showed participants reported both negative and positive consequences from their MS experiences. Higher levels of Demoralization and Deteriorated Relationships were related to decreased well-being. However, no association was found between Benefit Finding and psychological well-being. Benefit Finding was also unrelated to optimism, and the disease-related variables (mobility, fatigue). Only positive reappraisal coping was predictive of reporting of benefits which lends support to the notion that it is a coping strategy. To examine the effects of mobility the sample was divided into three groups: normal gait, mild gait problems but not using aids and those who require aids for mobility. Significant differences between the mobility groups were found on Demoralization and fatigue levels. As participants� difficulties with mobilisation increased so too did their levels of demoralisation. However, those with mild gait problems reported fatigue levels comparable with those experiencing more complex gait difficulties. No differences were found between the groups on the general psychological measures, which may indicate some form of resilience or psychological adaptation occurring. More generally, results showed that participants who were more optimistic, less fatigued, and used less of particular coping strategies (either less avoidant coping or less blaming self or others) to deal with their MS problems reported higher well-being (less demoralisation, less psychological distress and higher positive functioning). In conclusion, the use of multi-dimensional outcomes enabled a comprehensive examination of well-being and highlighted the effects of specific illness-related factors and coping strategies. As demonstrated in this study, despite the adversity of living with MS, people are able to maintain a healthy sense of self and their relationships, and report benefits from their experiences.
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Allen, James. "The public goods game on multiplex networks." Thesis, University of Surrey, 2018. http://epubs.surrey.ac.uk/845834/.
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Cooperation is acting in the interests of one’s social group, often at a cost to yourself. When the level of cooperation is observed in the laboratory, people cooperate more often, and at higher levels than are predicted by standard theories. In this thesis I find two novel ways in which cooperation on multilayered populations is increased. These models contribute to an understanding of how people cooperate in real-world social situations, and help us to explain why people cooperate as much as they are observed to do. In each study I model the tension between the individual and the group using the public goods game. This game is played on a structured population defined by a multilayered network. Each layer represents a different sphere of influence on the player’s decision to cooperate or defect. The first model studies the effect of a player choosing whether to cooperate or defect on either all layers simultaneously (synchronously) or on one layer at a time (asynchronously). Updating asynchronously leads to increased cooperation across a number of different parameter regimes. This demonstrates a new way in which cooperation can be increased in a system with multiple influences, and also helps to understand exactly why cooperation is increased in multilayered systems. Inspired by empirical examples, the second model adds to the standard model of the public goods game on networks in two ways. The first is to include conditional cooperators, and the second is the addition of a layer of social influence. This combination of economic and social influence has not been considered in previous models of the public goods game, and I find that this additional layer of influence results in high levels of cooperation. In the final chapter, I study these dynamics on more realistic network structures, with results echoing empirical findings under certain parameters.
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De, Paoli Damien, and mikewood@deakin edu au. "Multiple strategy process migration." Deakin University. School of Computing and Mathematics, 1996. http://tux.lib.deakin.edu.au./adt-VDU/public/adt-VDU20051110.115628.
Full textAbstract:
The future of computing lies with distributed systems, i.e. a network of workstations controlled by a modern distributed operating system. By supporting load balancing and parallel execution, the overall performance of a distributed system can be improved dramatically. Process migration, the act of moving a running process from a highly loaded machine to a lightly loaded machine, could be used to support load balancing, parallel execution, reliability etc.
This thesis identifies the problems past process migration facilities have had and determines the possible differing strategies that can be used to resolve these problems. The result of this analysis has led to a new design philosophy. This philosophy requires the design of a process migration facility and the design of an operating system to be conducted in parallel.
Modern distributed operating systems follow the microkernel and client/server paradigms. Applying these design paradigms, in conjunction with the requirements of both process migration and a distributed operating system, results in a system where each resource is controlled by a separate server process. However, a process is a complex resource composed of simple resources such as data structures, an address space and communication state. For this reason, a process migration facility does not directly migrate the resources of a process. Instead, it requests the appropriate servers to transfer the resources. This novel solution yields a modular, high performance facility that is easy to create, debug and maintain. Furthermore, the design easily incorporates providing multiple migration strategies.
In order to verify the validity of this design, a process migration facility was developed and tested within RHODOS (ResearcH Oriented Distributed Operating System). RHODOS is a modern microkernel and client/server based distributed operating system. In RHODOS, a process is composed of at least three separate resources: process state - maintained by a process manager, address space - maintained by a memory manager and communication state - maintained by an InterProcess Communication Manager (IPCM). The RHODOS multiple strategy migration manager utilises the services of the process, memory and IPC Managers to migrate the resources of a process. Performance testing of this facility indicates that this design is as fast or better than existing systems which use faster hardware. Furthermore, by studying the results of the performance test
ing, the conditions under which a particular strategy should be employed have been identified.
This thesis also addresses heterogeneous process migration. The current trend is to have islands of homogeneous workstations amid a sea of heterogeneity. From this situation and the current literature on the topic, heterogeneous process migration can be seen as too inefficient for general use. Instead, only homogeneous workstations should be used for process migration. This implies a need to locate homogeneous workstations. Entities called traders, which store and disseminate knowledge about the resources of several workstations, should be used to provide resource discovery. Resource discovery will enable the detection of homogeneous workstations to which processes can be migrated.
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Reddy, Brian P. "Multiple criteria approaches to public health decision-making." Thesis, University of Sheffield, 2017. http://etheses.whiterose.ac.uk/16605/.
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Boström, Inger. "Multipel skleros – hög prevalens i Värmland? : En epidemiologisk studie." Thesis, Nordic School of Public Health NHV, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:norden:org:diva-3259.
Full textAbstract:
Syftet med denna studie var att beräkna preliminär prevalens för sjukdomen multipel skleros (MS) i Värmland, med prevalensdag 21 december 2002, och jämföra den med andra prevalensstudier i Sverige. Utifrån patientjournaler vid länets sjukvårdsinrättningar noterades basala och medicinska data på ett registreringsformulär. För klassificering av MS har Poser ́s kriterielista tillämpats och granskningen av journaler har utförts av specialist neurologer. Prevalensen för definite/probable MS i Värmland, baserad på siffror som var insamlade augusti 2004, var 151/105 (95% CI 136-165), för kvinnor var prevalensen 211/105 (95% CI 187-235) och för män 89/105 (95% CI 73-105), vilket innebär att MS var 2,37 gånger vanligare för kvinnor. Vid jämförelse av den preliminära prevalens för Värmland och Västerbotten visade det sig att Värmland hade nästan lika hög prevalens och kan liksom Västerbotten betecknas som högriskområde för MS.The purpose of this study was to estimate the preliminary prevalence of multiple sclerosis (MS) in the County of Värmland, with prevalence date 21 December 2002, and to compare this with other prevalence studies in Sweden. The clinical data of the patients were collected from medical files at the medical care facilities in the county. For classification of MS the criteria by Poser were used. The diagnoses were scrutinised by neurologists. Based on the collected data, August 2004 the prevalence of definite/probable MS in Värmland is 151/105 (95% CI 136-165), for women 211/105 (95% CI 187-235), for men 89/105 (95% CI 73-105), resulting in a female to male ratio of 2,37. When comparing these results with prevalence numbers from Västerbotten County in the north of Sweden and Gothenburg respectively, our prevalence number reaches the level of that from Västerbotten, indicating that Värmland, as well as Västerbotten, is a high risk zone for MS.
ISBN 91-7997-154-7
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Pearson-Woodd, Nicolas John. "A multiple case study of violence in public houses." Thesis, University of Nottingham, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.285598.
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Wallenius, Hannele. "Implementing interactive multiple criteria decision methods in public policy /." Jyväskylä : University of Jyväskylä, 1991. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=005963002&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.
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O'Brien, Daniel Gerard, and n/a. "Broadband matching and distortion performance relating to multiple subcarrier multiplexed photonic systems." University of Canberra. Information Sciences & Engineering, 1992. http://erl.canberra.edu.au./public/adt-AUC20060821.095055.
Full textAbstract:
This thesis describes the outcome of study to investigate methods of
broadband matching to photonic devices such as lasers and high speed detectors.
The thesis is divided into two areas of interest relating to the design of
broadband fiber optic links.
The first area is the application of numerical methods and commensurate
line methods to the design of compact equalisers which allow an improved
transducer power gain over a wide band. It is shown that physically small
equalisers can yield an improvement of 4 dB over a 2 GHz bandwidth.
The second area considered is the distortion inherent in a laser diode.
Detailed measurements of the second order and intermodulation products
are given. A small signal perturbation analysis is presented which helps to
explain the observed distortion products. The results of numerical
simulation of the distortion using a state variable implementation of the full
rate equations and related first, second and intermodulation equations is
presented and possible methods of reducing the distortion are explored. It is
shown that in principle the distortion could be reduced by pre-generating
the distortion and adding an inverted form of the distortion to the
transmitted signal. The distortion can then be corrected in the fiber and
simulation studies suggest that an improvement of 13 dB optical or 26 dB
electrical may be possible.
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Hahn, Kyungdong. "Economies with public projects : theory and experimental evidence /." Diss., This resource online, 1995. http://scholar.lib.vt.edu/theses/available/etd-06062008-162457/.
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Wagg, Catherine Anne, and cathy wagg@rmit edu au. "Finding meaning: differentiating the multiple discourses of the Potter farmland plan." RMIT University. Global Studies, Social Science and Planning, 2009. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20091112.121423.
Full textAbstract:
This study explores the meanings that people attributed to their involvement in a participatory on-farm practice change project. Three techniques of discourse analysis were used. The first two identify the diversity among narratives of the participants and explores the origin of these differences. The third technique examined differences and tensions within and across the narratives to identify the discourses that were operating. Participation was found to be mediated through discourse as agents created and reproduced some discourses through their many social acts. For example, some participants recalled incidences of feeling excluded when they presented an alternative understanding of the project. As a result, these people tended to reduced their involvement rather than explore the differences. The project's discourses therefore routinised the participatory experience and tended to lock the narrative in time despite over two decades of rapid social change. Thi s meant the project discourse mediated a favoured type of participation, one that met a symbolic character rather than the particular farming practices it promoted. The discourses reveal different patterns of sense making among participants involved in the same event. Uneven participation is comprehended from the multiple patterns as a consequence of the participants' discursive practices. Articulating differences in discursive design will assist to create conditions useful for an authentic communication among participants engaged in change programs.
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Byrd, Christopher Merrill. "Public-Private Partnerships for Higher Education Infrastructure: A Multiple-Case Study of Public-Private Partnership Models." Thesis, Virginia Tech, 2013. http://hdl.handle.net/10919/19287.
Full textAbstract:
The use of public-private partnerships is a growing trend in the United States. However, these arrangements\' job creation abilities have not fully been studied. The nature of these arrangements allows for a wide variety of organizational structures. This thesis analyzes differing public-private partnership models for their job creation efficiency. The characteristics present in these arrangements are discussed. This thesis is a multiple-case study of three distinct public-private partnerships for higher education infrastructure. The three cases presented are Clemson University\'s International Center for Automotive Research, the University of Washington\'s South Lake Union Medical Research Complex, and Louisiana State University\'s Digital Media Center. The findings of this thesis are that public-private partnership models with substantial upfront non-public investment can create jobs more efficiently from the public sector\'s perspective. The public-private partnership models that create jobs more efficiently have the characteristics of stability, capacity, and collaboration.Master of Arts
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Beecher, Ann B. "Wayfinding tools in public library buildings: A multiple case study." Thesis, University of North Texas, 2004. https://digital.library.unt.edu/ark:/67531/metadc4470/.
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Wayfinding is the process of using one or more tools to move from one location to another in order to accomplish a task or to achieve a goal. This qualitative study explores the process of wayfinding as it applies to locating information in a public library. A group of volunteers were asked to find a selection of items in three types of libraries-traditional, contemporary, and modern. The retrieval process was timed and the reactions of the volunteers were recorded, documented, and analyzed. The impact of various wayfinding tools-architecture, layout, color, signage, computer support, collection organization-on the retrieval process was also identified. The study revealed that many of the wayfinding tools currently available in libraries do not facilitate item retrieval. Inconsistencies, ambiguities, obstructions, disparities, and operational deficiencies all contributed to end-user frustration and retrieval failure. The study suggests that failing to address these issues may prompt library patrons-end users who are increasingly interested in finding information with minimal expenditures of time and effort-may turn to other information-retrieval strategies and abandon a system that they find confusing and frustrating.
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Borah, Deva Kanta, and dborah@nmsu edu. "Detection and Estimation in Digital Wireless Communications." The Australian National University. Research School of Information Sciences and Engineering, 2000. http://thesis.anu.edu.au./public/adt-ANU20050506.015503.
Full textAbstract:
This thesis investigates reliable data communication techniques for wireless channels. The problem of data detection at the receiver is considered and several novel detectors and parameter estimators are presented.¶
It is shown that by using a noise-limiting prefilter, with a spectral support at least equal to the signal part of the received signal, and sampling its output at the Nyquist rate, a set of sufficient statistics for maximum likelihood sequence detection (MLSD) is obtained.¶
Observing that the time-variations of the multipaths in a wireless channel are
bandlimited, channel taps are closely approximated as polynomials in time. Using this representation, detection techniques for frequency-flat and frequency-selective channels are obtained. The proposed polynomial predictor based sequence
detector (PPSD) for frequency-flat channels is similar in structure to the MLSD that employs channel prediction. However, the PPSD uses {\em a priori} known
polynomial based predictor taps. It is observed that the PPSD, without any explicit knowledge of the channel autocovariance, performs close to the Innovations based MLSD.¶
New techniques for frequency-selective channel estimation are presented. They are based on a rectangular windowed least squares algorithm, and they employ a
polynomial model of the channel taps. A recursive form of the least squares algorithm with orthonormal polynomial basis vectors is developed. Given the appropriate window size and polynomial model order, the proposed method outperforms the conventional least mean squares (LMS) and the exponentially weighted recursive least squares (EW-RLS) algorithms. Novel algorithms are proposed to obtain near optimal window size and polynomial model order.¶
The improved channel estimation techniques developed for frequency-selective channels are incorporated into sliding window and fixed block channel estimators. The sliding window estimator uses received samples over a time window to calculate the channel taps. Every symbol period, the window is moved along another symbol period and a new estimate is calculated. A fixed block estimator uses all
received samples to estimate the channel taps throughout a data packet, all at once. In fast fading and at a high signal-to-noise ratio (SNR), both techniques
outperform the MLSD receivers which employ the LMS algorithm for channel estimation.¶
An adaptive multiuser detector, optimal in the weighted least squares (WLS) sense, is derived for direct sequence code division multiple access (DS-CDMA) systems. In a multicellular configuration, this detector jointly detects the users within the cell of interest, while suppressing the intercell interferers in a WLS sense. In the absence of intercell interferers, the detector reduces to the well-known multiuser MLSD structure that employs a bank of matched filters. The relationship between the proposed detector and a centralized decision feedback detector is derived. The effects of narrowband interference are investigated and compared with the multiuser MLSD.¶
Since in a fast time-varying channel, the LMS or the EW-RLS algorithms cannot track the channel variations effectively, the receiver structures proposed for single user communications are extended to multiuser DS-CDMA systems. The fractionally-chip-spaced channel taps of the convolution of the chip waveform with the multipath channel are estimated. Linear equalizer, decision feedback equalizer
and MLSDs are studied, and under fast fading, as the SNR increases, they are found to outperform the LMS based adaptive minimum mean squared error (MMSE) linear receivers.
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Vivekananda, Kitty. "Long-term multiple stressors, coping and academic performance /." View thesis View thesis, 2001. http://library.uws.edu.au/adt-NUWS/public/adt-NUWS20030507.140731/index.html.
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Nimkar, Swateja. "Characteristics of Marijuana Users Compared to Multiple Drug Users." TopSCHOLAR®, 2006. http://digitalcommons.wku.edu/theses/255.
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This study examines drug use behavior in a self-described sample of users. Comparisons are made between subjects whose only illicit drug use is marijuana and those who use both marijuana and other drugs. Data are from the DRUGNET study (1996, 1998, 1999), a multi-panel study conducted over the internet from 1996 - 1998. This sample was predominately white, male, young, and college educated. The majority of respondents were employed with incomes in the $50,000 - $60,000 (USD) range. A subset of respondents to the DRUGNET survey was selected for this analysis. Respondents had to be at least 18 years of age, a US citizen and report marijuana drug use (n = 283). The major finding from this study is that there were no significant differences between the two groups on any variable measured other than gender, household income and the age of onset of marijuana use. Women are more likely to report using marijuana alone while males are more likely to report using marijuana and other drugs. The individuals having low and middle class household income were more likely to report the use of marijuana and other drugs compared to the upper middles class income groups who were more likely to report the use of marijuana alone. After Bonferroni's adjustment was done, it was observed that the mean age of onset for the group who used marijuana alone was greater in comparison to the group who used marijuana along with other drugs. While this study is the first one to make this comparison and may have implications for drug education, policy, and treatment. The result obtained from this study may be an artifact of the study design and/or sample.
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Foster, Kate Yvonne, and kate foster@dsto defence gov au. "An investigation of the use of past experience in single and multiple agent learning classifier systems." Swinburne University of Technology. Centre for Intelligent Systems & Complex Processes, 2005. http://adt.lib.swin.edu.au./public/adt-VSWT20051117.112922.
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The field of agent control is concerned with the design and implementation of components that form an agent's control architecture. The interaction between these components determines how an agent?s sensor data and internal state combine to direct how the agent will act. Rule-based systems couple sensing and action in the form of condition-action rules and one class of such systems, learning classifier systems, has been extensively used in the design of adaptive agents. An adaptive agent explores an often unknown environment and uses its experience in its environment with the aim of improving its performance over time. The data an adaptive agent receives regarding the current state of its environment might be limited and ambiguous. In learning classifier systems, three different approaches to the problem of limited and ambiguous data from the environment have been: (1) to enable the agent to learn from its past experience, (2) to develop sequences of rules (in which rules may be linked implicitly or explicitly) and (3) multiagent LCSs.
This thesis investigates the use of an adaptive agent?s past experience as a resource with which to perform a number of functions internal to the agent. These functions involve developing explicit sequences of rules, detecting and escaping from infinite loops, and firing and reinforcing rules.
The first part of this thesis documents the design, implementation and evaluation of a control system that incorporates these functions. The control system is realised as a learning classifier system and is evaluated through experiments in a number of environments that provide limited and ambiguous stimuli. These experiments test the impact of explicit sequences of rules on the performance of a learning classifier system more thoroughly than previous research achieved. The use of explicit sequences of rules results in mixed performance in these environments and it is shown that while the use of these sequences in simple environments enables the rule space to be more effectively explored, in complex environments the behaviours developed by these sequences result in the agent stagnating more often in corners of the environment.
Rather than endowing the rule-base with more rules, as in previous research with explicit sequences of rules, it is proposed that multiple interacting agents may enhance the exploration of the rule space in more complex environments. This approach is taken in the second part of this thesis, where the control system is used with multiple agents that interact by sharing rules. The aim of this interaction is to enhance the rule discovery process through cooperation between agents and thus improve the performance of the agents in their respective environments. It is shown that the benefit obtained from rule sharing is dependent on the environment and the type and amount of rule sharing used and that rule sharing is generally more beneficial in complex environments compared to simple environments. The properties of the rule-bases developed in these environments are examined in order to account for these results and it is shown that the type and amount of rule sharing most useful in each environment are dependent on these properties.
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Stephenson, Janet, and n/a. "Values in space and time : a framework for understanding and linking multiple cultural values in landscapes." University of Otago. Department of Geography, 2006. http://adt.otago.ac.nz./public/adt-NZDU20061030.154114.
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When new development threatens a valued landscape it is not just the physical landscape that is being affected, but the collective memories, meanings and identities that the landscape holds. Planning theory and practice currently offer relatively little guidance as to how to address meaning and value, particularly at a landscape scale.
Recent literature from a variety of disciplines has stressed the need to develop holistic models of understanding landscape. Particular emphasis has been laid on the absence of integration of disciplinary approaches, and the need to involve communities in defining what is important and distinctive about their own landscapes.
The thesis sets out to develop a conceptual framework to assist in understanding multiple cultural values in landscapes. Although the primary focus of the research is to address the perceived shortcomings in planning theory and practice, its potential relevance to inter-disciplinary work also forms a major component of the research approach.
Values in landscapes include those expressed by associated communities and those identified through a variety of disciplinary approaches. Using case studies, the research explores the nature and range of landscape values as expressed by those with special associations with particular landscapes. It also examines the nature of the meanings and values ascribed by disciplines with an interest in landscape, and how various disciplines model landscape so as to convey these values.
Analysis of these findings generates a landscape framework consisting of two related models. The Cultural Values Model offers a conceptual structure with which to consider the surface and embedded values of landscapes in terms of forms, practices and relationships. The Dimensional Landscape Model provides a structured way of linking expressed values to the landscape, using dimensional concepts of nodes, networks, spaces, webs and layers.
The landscape framework is found to be useful not only for generating a comprehensive picture of key landscape values, but also in offering an integrated approach that has utility both for planners and for other landscape-related disciplines.
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Huang, Chi. "Visuality and tacit knowledge the application of multiple intelligences theory to the design of user expeience in interactive multimedia contexts /." Australasian Digital Thesis Program, 2006. http://adt.lib.swin.edu.au/public/adt-VSWT20070214.163710/index.html.
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Thesis (DDes) - Faculty of Design, Swinburne University of Technology, 2006.Submitted in partial fulfilment of the requirements of the degree of Professional Doctorate in Design, Faculty of Design, Swinburne University of Technology - 2006. Typescript. Bibliography: p. 76-85.
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Alamian, Arsham. "Multiple Behavioral Risk Factors for Chronic Diseases and Public Health Implications." Digital Commons @ East Tennessee State University, 2012. https://dc.etsu.edu/etsu-works/1382.
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Haug, Beata Ewa. "Third-Party Administrators in Public-Private Partnerships: A Multiple Case Study." ScholarWorks, 2015. https://scholarworks.waldenu.edu/dissertations/1824.
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Local public agencies turn to public-private partnerships (PPPs) to allow greater participation by private firms in delivering public services. In the last 25 years, private organizations had been reluctant to form PPPs with local government agencies because of the complex procurement processes and the bureaucratic business environment. Guided by the decision theory and complex adaptive systems theory, the purpose of this multiple case study was to identify what information leaders within third-party administrators (TPAs) need regarding the contracting process in the formation of PPPs. The data collection process consisted of face-to-face interviews with 4 executive leaders of 3 Wisconsin state licensed TPAs and examination of contracts and plan service agreements (PSAs) between TPAs and local government agencies. Dada was analyzed using the Yin 5-step data analysis method and cross-case analysis. The results indicated that TPA leaders must understand collaborative leadership, key players, roles and responsibilities, and specialized services in the formation of a PPP; change and transfer of controlling interest, and understanding the strengths and weakness of contract provisions are complex business systems that influence the decision to form a PPP; ERISA and compliance with applicable federal and state laws are critical contract stipulations to consider in the formation of PPPs; that market assessment, health care reform, and transparency between private and public partners are critical in the formation of PPPs. The implications for social change include new insights for PPP leaders that may enhance the effectiveness of social services and save taxpayers' money.
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Huang, Chi, and n/a. "Visuality and tacit knowledge the application of multiple intelligences theory to the design of user expeience in interactive multimedia contexts." Swinburne University of Technology, 2006. http://adt.lib.swin.edu.au./public/adt-VSWT20070214.163710.
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The major challenge for multimedia designers is to create user experiences that enrich the reception of content, designer�s traditional reliance on intuition not ensuring audience�s interest or understanding. The developing philosophy of user-centred design argues that designers should begin from an appreciation of their audience. In design there are various positions on how to achieve this, ranging from traditional market research through psychological, ethnographic, anthropological and sociological research to the direct involvement of users in the design process. This study draws on established knowledge about the cognitive processes, psychological motivations and preferences of user groups to advance a model for better-targeted and more effective design. In particular, it uses Howard Gardener�s multiple intelligences theory to extend design thinking. Where a specific audience is apparent multiple intelligences theory implies that (1) the interface should match user�s perceptual tools, cognitive styles and responses and (2) there is far greater scope than presently recognized to vary the design of the graphical user interface. The research explores how interactive multimedia can harness the �language of vision� (Johannes Itten) for certain audiences, in this case Taiwanese drawing students aiming to enter tertiary art and design programs where high academic drawing skills are an important selection criterion. The high �visual intelligence� of the target audience indicates their heightened capacity to process visual concepts and elements. The application of Gardner�s ideas is a speculative one, based on hypothesis and the formulation of an experimental graphical user interface environment built around predominantly visual cues. The designed outcome incorporates knowledge and understanding that is widely applicable to GUI design, challenging designers to develop multimedia products with innovative, imaginative design approaches that cater for the different needs and interests of users where the audience is a specific and identifiable one.
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Chen, Shu-Fen, and res cand@acu edu au. "Cooperative Learning, Multiple Intelligences and Proficiency: application in college English language teaching and learning." Australian Catholic University. Faculty of Education, 2005. http://dlibrary.acu.edu.au/digitaltheses/public/adt-acuvp120.25102006.
Full textAbstract:
The purpose of this research is to investigate whether the implementation of Cooperative Learning (CL) activities, incorporating the insights given by Howard Gardner’ (1993) theory of Multiple Intelligences (MI) and the notion of Whole Language Approach (WLA) in college EFL classrooms will have a positive effect on students’ language proficiency and attitude. A quasi-experimental study was developed. The site of this study was in an EFL classroom in a Taiwanese College. The subjects were from the researcher’s three English classes at Chung Hwa Institute of Medical Technology during one semester. Many learning activities based on Gardner’s theory of Multiple Intelligences were used while a Cooperative Learning approach was practiced. The data for this study was collected from three sources. One was from the subjects’ questionnaires on attitudes and on motivation, regarding Cooperative Learning and Multiple Intelligences. Another was from student interviews. The third was from the students’ test scores on their language proficiency tests. The results of the study showed that the experimental group that was taught using the ideas based on CL and MI outperformed the group based on CL, and the control group, on the Simulate English General Proficiency tests for the four language skills. Though there were no significant differences among them within this short-time study, the motivation in learning English was enhanced a great deal for the experimental group that was taught using the CL and MI ideas. Based upon the insight gained from this study, CL, MI, WLA and Language Learning Center were thus recommended to be integrated into the Junior College English curriculum. Pedagogical implications for the application of CL and MI in an EFL classroom were developed. Above all, suggestions for teacher development in CL and MI were proposed. Finally, suggestions for future research have been recommended.
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Nguyen, Hoang Nghia. "Survivable mesh-network design & optimization to support multiple QoP service classes /." Connect to thesis (via ADT), 2009. http://adt.ecu.edu.au/adt-public/adt-ECU2010.0003.html.
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Zaroli, Christophe. "Global multiple-frequency S-wave tomography of the Earth’s mantle." Strasbourg, 2010. https://publication-theses.unistra.fr/public/theses_doctorat/2010/ZAROLI_Christophe_2010.pdf.
Full textAbstract:
Afin de mieux contraindre la structure interne de la Terre, de nouveaux développements théoriques, sur la propagation des ondes, ont émergé ces dernières années. Une de ces nouvelles méthodes est la tomographie multi-fréquences, qui vise à exploiter la dépendance en fréquence des temps de parcours des ondes de volume, liée aux effets de diffraction. En utilisant cette méthode, cette thèse a pour objectif d'obtenir un modèle tomographique 3-D du manteau en ondes de cisaillement à ``haute-résolution'', qui puisse contribuer à améliorer nos connaissances sur la dynamique de la TerreFor better constraining the structure of the Earth's interior, new theoretical developments on seismic wave propagation have emerged in recent years, and received increasing attention in tomography. One of these new methods is the multiple-frequency tomography, which aims at exploiting the frequency-dependency of body wave travel times related to diffraction effects. In this thesis, we have applied this method in order to obtain a ``high-resolution'' 3-D shear-wave tomographic model of the mantle, that could contribute to a better understanding of the Earth's dynamics
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Gaubatz, Gunnar. "Versatile Montgomery Multiplier Architectures." Digital WPI, 2002. https://digitalcommons.wpi.edu/etd-theses/538.
Full textAbstract:
Several algorithms for Public Key Cryptography (PKC), such as RSA, Diffie-Hellman, and Elliptic Curve Cryptography, require modular multiplication of very large operands (sizes from 160 to 4096 bits) as their core arithmetic operation. To perform this operation reasonably fast, general purpose processors are not always the best choice. This is why specialized hardware, in the form of cryptographic co-processors, become more attractive.
Based upon the analysis of recent publications on hardware design for modular multiplication, this M.S. thesis presents a new architecture that is scalable with respect to word size and pipelining depth. To our knowledge, this is the first time a word based algorithm for Montgomery's method is realized using high-radix bit-parallel multipliers working with two different types of finite fields (unified architecture for GF(p) and GF(2n)).
Previous approaches have relied mostly on bit serial multiplication in combination with massive pipelining, or Radix-8 multiplication with the limitation to a single type of finite field. Our approach is centered around the notion that the optimal delay in bit-parallel multipliers grows with logarithmic complexity with respect to the operand size n, O(log3/2 n), while the delay of bit serial implementations grows with linear complexity O(n).
Our design has been implemented in VHDL, simulated and synthesized in 0.5μ CMOS technology. The synthesized net list has been verified in back-annotated timing simulations and analyzed in terms of performance and area consumption.
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Tajouri, Lotfi, and n/a. "Gene Expression Analysis and Genetic Studies in Multiple Sclerosis." Griffith University. School of Health Science, 2005. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20060111.123933.
Full textAbstract:
Multiple Sclerosis (MS) is a neurodegenerative disease of the central nervous system (CNS). As part of this disorder the myelin sheath undergoes degeneration, leading to alterations in the conductivity of axons, and impaired function. The onset of the disease occurs in young adults and clinical pathology is characterised by varying severity. These include i) Relapsing Remitting MS (RR-MS), ii) Secondary Progressive MS (SP-MS) and iii) Primary Progressive MS (PP-MS). MS is more prevalent in women and accounts for more than two thirds of all MS sufferers. MS is considered to be a multifactorial disorder with both genetic and environmental components. The prevalence of MS is dependent on geographical localisation, with lower sunlight exposure linked to higher prevalence. Also, studies show an increased risk in close relatives, or in identical twins, indicating a significant genetic component to the disorder. There are a number of genes that may plausibly be involved in MS pathophysiology. These include myelin-related genes, such as the myelin basic protein (MBP), immune-related genes, such FC receptor and osteopontin, and heat shock proteins such as xb crystallin. These candidate genes have been implicated in a variety of ways but usually through immunological and/or genetic studies. One of the most consistent findings in recent years has been the association of disease with alterations in the specific major histocompatibility complex (MHC) localised to chromosome 6p21.3, and includes MHC I, II, III. Genome wide screens have permitted the identification of loci in the genome, which are associated with MS susceptibility. The number of genes involved in MS is unknown and several case-control association studies have been undertaken to reveal the involvement of potential candidate genes. In general terms, current research is aimed at determining allelic variation of candidate genes. Such genes have been implicated in MS because they reside within susceptible regions of the chromosome associated with MS or they have a plausible potential pathophysiological role in MS. Candidate loci investigated in this study, for association with MS susceptibility, include members of the nitric oxide synthase family of metabolic proteins (inducible NOS, iNOS/NOS2A and neuronal NOS, nNOS), methylenetetrahydrofolate reductase (MTHFR), catechol-O-methyl transferase (COMT), and vitamin D receptor (VDR). The MS population used in all studies consisted of over 100 MS cases and gender, age and ethnicity matched controls. In our study of inducible and neuronal NOS genes, PCR based assays were developed to amplify a region of both promoters that contained known microsatellite variation. Supporting phyisological data suggests that the neuroinflammatory aspects of MS are associated with aberrant NO production, which may be due to aberrant regulation of NOS activity. Specific amplified products were identified by fluorescent capillary electrophoresis and allele frequencies were statistically compared using chi-squared analysis. In the nNOS and iNOS study, no association was identified with allele frequency variation and MS susceptibility (nNOS: ?2=5.63, P=0.962; iNOS: ?2=3.4; P=0.082). Similarly, no differences in allele frequencies were observed for gender or clinical course for both markers (Pvalue greater than 0.05). In short, results from this study indicate that the NOS promoter variations studied do not play a significant role in determining susceptibility to MS in the tested population. The COMT and MTHFR genes are localised at 22q12-13 and 1p36.3 respectively, regions of the genome that have been found to be positively associated with MS susceptibility. In our research, we set out to examine the G158A change in the 4th exon of the COMT gene. This functional mutation leads to an amino acid change (valine to methionine) that is directly associated with changes in the activity of COMT. The MTHFR enzyme plays a role in folate metabolism, and can be implicated in the turnover of homocysteine. Previous investigations have shown that high levels of homocysteine are encountered in MS patients, where it is also linked to demyelination in the CNS. In our study the aim was to examine the C677T variation (alanine to valine amino acid change) in the exon 4 coding region of the MTHFR gene and the G158A variation in the COMT gene. Restriction fragment length polymorphism (RFLP) analysis and gel electrophoresis was used to identify specific alleles for both COMT and MTHFR. However, as with the NOS study, no specific association was identified between MS susceptibility and variation for either of the tested COMT or MTHFR (Pvalue greater than 0.05) variants. In a final genomic investigation of the MS population, three variations in the VDR gene were analysed for association with MS susceptibility and pathology. Using RFLP analysis, three VDR variants were investigated with genotypes detected using the Taq I, Apa I and Fok I restriction enzymes. In contrast to previous genotypic analyses, this study did show a positive association, specifically between the functional variation in exon 9 of the VDR gene and MS (Taq I, 2= 7.22, P= 0.0072). Interestingly, the Apa I variant of VDR was also found to be associated with MS ( 2=4.2, P=0.04). The Taq I and Apa I variants were also found to be in very strong and significant linkage disequilibrium (D'=0.96, Pvalue less than 0.0001) and their associations were more prominent with the progressive forms of MS (SP-MS and PP-MS). In addition to genotypic analysis of a clinical population, additional research was undertaken to identify novel targets for MS susceptibility studies. Global gene expression analysis was undertaken using comparative subtractive fluorescent microarray technology to examine differences in gene activity (expression) in age and sex matched MS plaque tissue and anatomically matched normal white matter (NWM). MS plaques were obtained post mortem from MS sufferers with no drug history in the last two months before death and matched anatomically to healthy white matter from donors with no previous neurological disorders. Target arrays consisted of 5000 cDNAs and analysis was conducted using the Affymetrix 428 scanner. In this way, 139 genes were shown to be differentially regulated in MS plaque tissue compared to NWM. Of these, 69 genes showed a common pattern of expression in the chronic active and acute plaque tissues investigated (Pvalue less than 0.0001, a=0.73); while 70 transcripts were uniquely differentially expressed ( 1.5-fold) in either acute or chronic active lesions. To validate the gene expression profile results, quantitative real time reverse transcriptase (RT) PCR (Q-PCR) analysis was performed. 12 genes were selected because they were shown to be differentially expressed by array analysis in this study, or because of their involvement in MS pathology. These included transferrin (TF), superoxide dismutase 1 (SOD1), glutathione peroxidase 1 (GPX1), glutathione S-transferase pi (GSTP1), crystallin, alpha-B (CRYAB), phosphomannomutase 1 (PMM1), tubulin beta-5 (TBB5), inositol 1,4,5-trisphosphate 3-kinase B (ITPKB), calpain 1 (CAPNS1), osteopontin (SPP1 or OPN), as well as the signal transducer and activator of transcription 1 (STAT1) and protein inhibitor of activated STAT1 (PIAS1). Both absolute (copy number) and comparative differences in the relative levels of expression in MS lesions and NWM were determined for each gene. The results from this study revealed a significant correlation of real time PCR results with the microarray data, while a significant correlation was also found between comparative and absolute determinations of fold. As with the results of array analysis, a significant difference in gene expression patterning was identified between chronic active and acute plaque pathologies. For example, a up to 50-fold increase in SPP1 and ITPKB levels in acute plaques contrasted with the 5-fold or less increase in chronic active plaques (P less than 0.0.1, unpaired t-Test). Of particular note, gamma-amino butyric acid receptor ?2 (GABG2), integrin ?5 (ITGB5), complement component 4B (C4B), parathyroid hormone receptor 1 (PTHR1) were found up-regulated in MS and glial derived neurotropic factor ?2 (GDNFA2), insulin receptor (INSR), thyroid hormone receptor ZAKI4 (ZAKI4) were found down-regulated in MS. Data also revealed a decreased expression of the immune related genes STAT1 and PIAS1 in acute plaques. In conclusion, this research used both genomic analysis and technologies in gene expression to investigate both known and novel markers of MS pathology and susceptibility. The study developed tools that may be used for further investigation of clinical pathology in MS and have provided interesting initial expression data to further investigate the genes that play a role in MS development and progression.
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Niyonsenga, Theogene, and Cleophace Mwaulambo. "IT Governance Practices : A Multiple Case Study of Tanzanian Public Government Organizations." Thesis, Internationella Handelshögskolan, Högskolan i Jönköping, IHH, Informatik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-40064.
Full textAbstract:
Previous studies have been made on various aspects of IT governance in public government organizations in developing countries and revealed several major issues. However, due to limited knowledge, it is unclear what IT Governance (ITG) practice is in place in public organizations. The purpose of this study is therefore to investigate the adopted IT management practices and their influence on the effectiveness of IT management in the Tanzanian public government organization. A qualitative study was done using the holistic multiple case study strategy. Data was collected using the semi-structured interview method with heads of IT in three Tanzanian public government organizations. The analysis of this study showed that senior managers involvement in IT projects, Office of CIO and the IT leadership are key ITG practices adopted in the three Tanzanian public government organizations. Senior management involvement in IT projects was found to influence knowledge sharing through collaboration between IT and business units. Furthermore, the CIO office was found to influence the organization's decision-making through direct representation to the decision-making body by a person who monitors and issues IT directives. Furthermore, IT management was found to have an influence on simplifying knowledge sharing between IT and business units, as well as monitoring IT issues and issuing IT directives in the organization. Given these findings, our study contributes knowledge into the literature on IT governance with special emphasis on governmental organizations in developing countries.
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Castle, Marianne Q. L. "Immunogenetics of multiple sclerosis : an investigation of the alleles of the HLD-A region /." View thesis, 1995. http://library.uws.edu.au/adt-NUWS/public/adt-NUWS20030825.155933/index.html.
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Van, Sparrentak Kenneth J. "Building school resilience in an era of multiple threats." Thesis, Monterey, Calif. : Naval Postgraduate School, 2008. http://edocs.nps.edu/npspubs/scholarly/theses/2008/Sept/08Sep%5FVan%5FSparrentak.pdf.
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Thesis (M.A. in Security Studies (Homeland Security and Defense))--Naval Postgraduate School, September 2008.Thesis Advisor(s): Woodbury, Glen ; Morag, Nadav. "September 2008." Description based on title screen as viewed on November 5, 2008. Includes bibliographical references (p. 143-150). Also available in print.
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Joliffe, Edward Keith, and n/a. "Developing a multiple discourse model of analysis through an evaluation of the National Aboriginal and Torres Strait Islander Education Policy." University of Canberra. Education, 1995. http://erl.canberra.edu.au./public/adt-AUC20060802.170810.
Full textAbstract:
The overarching research problem for this study was the need to improve
upon rational models of policy analysis and delivery, to suit complex postmodern
implementation environments. A theoretical model suited to implementing and
evaluating major education reform initiatives was devised. Called the 'Multiple Discourse Model', it was grounded in systems theory, containing elements
reminiscent of social systems, organisational and structural functionalist research,
especially that of Hoy and Miskel (1982)1. However the model was also designed
to incorporate a parallel naturalistic analysis reminiscent of postmodern critical
pragmatic approaches, such as those explored by Cherryholmes (1994)2. Over a
period of five years, this model was developed through an evaluation of the
implementation of the National Aboriginal and Torres Strait Islander Education Policy (AEP) in the Australian Capital Territory government secondary schools
sector.
The distinguishing feature of the study's methodology was its multiperspective
analysis, an approach suggested by Mclaughlin (1987)3 to take account
of the differing communities of discourse which exist in a reformist policy
implementation environment.
To operationalise the research problem, dimensions of policy effectiveness
were articulated. These were addressed through a comprehensive set of research
indicators, extracted from the AEP's national policy goals and the local strategic and
operational plans. Data aimed at judging the effectiveness of implementation were
collected from multiple sources using multiple research instruments. These data
were analysed in three stages using a purpose-designed computer program which
could cross-reference between the four interacting dimensions of research
indicators, research instruments, data sources, and potential variables modifying
policy/program outcomes.
It was found that this model produced clear conclusions about the
effectiveness of AEP implementation in the delimited sector, within the framework
of the AEP's own policy assumptions. The model also provided insights into critical
issues which are generalisable to the national context, such as the power of cultural
hegemony and the socio-political predicament of Aboriginal and Torres Strait
Islander dispossession. As a methodology, the model was found to have a number
of technical advantages, including its capacity for focussing on selected areas of the
implementation environment, its provision of access to multiple levels of detail
amongst data and its possession of mechanisms for monitoring its own internal
validity.
The evaluation case study, used as the vehicle for the Multiple Discourse
Model's development, demonstrated that best-practice administration was in place
which enhanced short and medium-term policy/program outcomes. However, the
study's findings also suggested that a fundamental disjuncture existed between the
AEP's policy/administration paradigm and the conflicting assumptions of the primary
target communities, reinforcing the findings of Sykes (1986)4. The research results
suggested that despite measurable successful inputs, the planned long-term
outcomes of the AEP will not necessarily be achieved. No significant administrative
structures or actions were apparent which could resolve this lack of synchrony at the
interface between government delivery systems and 'grass roots' Aboriginal and
Torres Strait Islander community values. This raised doubts about whether any
systems approach, however well refined, could be socially useful not only for
evaluation, but also as a basis for reform policy and public administration in a
postmodern pluralist democratic setting. The evaluation was therefore used as a
locus for theoretical reflection as well.
A new policy paradigm is suggested, based on a power-sharing 'theory of
community', more in keeping with Aboriginal and Torres Strait Islander peoples'
aspirations for self determination and more likely to alleviate the so far unresolved
destructive effects of cultural and political dispossession.
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Walsh, Jason L., and jason walsh@rmit edu au. "Development & evaluation of multiple optical trapping of colloidal particles using computer generated structured light fields." RMIT University. Applied Sciences, 2010. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20100209.143544.
Full textAbstract:
Colloidal particles are small particles ranging in size from nanometres to micrometres suspended in a fluid. Amongst many scientific and biological applications, they have been used to model crystallisation, vitrification, and particle interactions along with the use of colloidal model systems for the study of the fundamental nature of the fluid-crystal and fluid-glass phase transitions. It has been shown that colloidal particles can be trapped and manipulated using strongly-focused light beams known as optical tweezers, and this has paved the way for research into the area of micromanipulation using optical trapping. Holographic elements can replace multiple lenses in creating large numbers of optical tweezers and this is known as holographic optical trapping (HOT). A computer generated hologram can be designed to create large structured light fields, consisting of multiple foci, to enable trapping of multiple particles in arbitrary configurations. The overall aim of this project was to design, develop and test the suitability of a simple, inexpensive optical trapping arrangement suitable for multiple optical trapping. To achieve this, a theoretically-exact expression for the wavefront of a single point source was implemented in the coding scheme, allowing for the fast creation of multiple point sources suitable for holographic optical trapping experiments. Compensation for the spherical aberration present in the focusing optics was implemented into the coding scheme. Kodalith photographic film was chosen as the holographic recording medium for its high contrast and availability. The film has proven to be a successful medium, when used to record photographically-reduced images of high-quality printouts of the computed diffraction pattern, as it was able to successfully reproduce complex light fields. It is believed that this will be the first time that this film has been implemented for optical trapping purposes. The main limitations concerning the performance of the holograms recorded on Kodalith were the phase nonuniformities caused by unevenness in the film thickness which resulted in a failure to separately resolve light traps separated by less than about 5 (Mu)m. Index matching of the film between sheets of flat glass helped to compensate for these limitations. Holographic optical trapping was successfully observed using a variety of different initial beam powers, holographic aperture settings and light field configurations. Trapping experiments on of two types of particles (PMMA and polystyrene) were successfully conducted, with as little as ~ 150 (Mu)W per trap being required for multiple polystyrene trapping. However, particles were weakly trapped and were easily dislodged at these powers, and a higher power per trap of around 1 mW is preferred. The use of a relatively low numerical aperture (NA) 50 mm SLR lens for focusing the holographic optical traps was successful, proving that optical trapping can be conducted without the use of high NA microscope-objective lenses commonly used in other set ups. Holographic trapping of colloidal particles was successfully conducted at RMIT University for the first time proving the validity of the coding scheme, the recording method and the trapping arrangement.
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Woodward, Helen Lynette. "Portfolios : narratives for learning : assessment processes and phenomenon across multiple environments /." View thesis, 1999. http://library.uws.edu.au/adt-NUWS/public/adt-NUWS20030814.100208/index.html.
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Sharma, Swati. "Brain atrophy estimation using magnetic resonance imaging : Application to multiple sclerosis." Strasbourg, 2011. https://publication-theses.unistra.fr/public/theses_doctorat/2011/SHARMA_Swati_2011.pdf.
Full textAbstract:
Cette thèse est consacrée à l'estimation de l'atrophie cérébrale longitudinale pour les patients atteints de sclérose en plaques. Tout d'abord, sur la base de leur robustesse à diverses sources d'erreur (inhomogénéité en intensité, bruit, distorsions géométriques, artefacts d'interpolation et présence de lésions), une évaluation des principales approches d'estimation de l'atrophie cérébrale est réalisée à l'aide de simulations d'une vérité terrain. Ensuite, une analyse statistique est effectuée afin d'estimer les incertitudes associées à l'atrophie mesurée. Un cadre générique est proposé pour construire des intervalles de confiance de l'atrophie estimée dans une région d'intérêt du cerveau. Une base d'apprentissage est utilisée pour obtenir ces intervalles de confiance pour un algorithme quelconque d'estimation de l'atrophie. Enfin, un cadre bayésien est proposé pour l'estimation conjointe d'une transformation non-rigide (à partir de laquelle l'atrophie est calculée) et du champ d'inhomogénéité en intensité présent dans les images. Cette approche bayésienne couplée aux techniques MCMC fournit un cadre rigoureux pour la construction d'intervalles de confiance de l'atrophie cérébraleThis dissertation is dedicated to estimation of longitudinal brain atrophy in patients with multiple sclerosis. First, an evaluation of widely used brain atrophy estimation approaches is carried out using simulated gold standards in order to test their robustness to various sources of error (bias-field inhomogeneity, noise, geometrical distortions, interpolation artefacts and presence of lesions). Next, statistical analysis of maps of volumetric change in an individual brain is performed in order to estimate the uncertainties associated with the measured atrophy. A generic framework for constructing confidence intervals for atrophy estimated in any region of interest in the brain is developed. With the help of a learning database, confidence intervals can be obtained for any atrophy estimation algorithm. Finally, a Bayesian framework is developed that allows for the estimation of a non-rigid transformation (from which atrophy is obtained through its Jacobian) and bias field inhomogeneity. MCMC sampling methods coupled with this framework make the construction of confidence intervals possible for the estimated atrophy