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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
201

Suivi tridimensionnel de la main et reconnaissance de gestes pour les Interfaces Homme Machine

Conseil, Simon 13 March 2008 (has links) (PDF)
L'interprétation automatique de gestes basée sur la vision par ordinateur offre de nouvelles possibilités d'interaction avec l'ordinateur, plus naturelles et intuitives qu'avec les périphériques classiques. Cependant, le canal gestuel est un moyen de communication particulièrement riche et la main un objet articulé complexe. Ainsi, l'interaction homme-machine gestuelle constitue un axe de recherche particulièrement actif avec un potentiel applicatif important.<br /> Dans ce contexte, notre travail a consisté à remplacer le fonctionnement d'un écran tactile par un système de vision stéréoscopique avec deux caméras. Ainsi, le problème fondamental a consisté à suivre, en temps réel, le mouvement de la main et des doigts à partir de leurs projections dans les images, avant d'en reconnaître la posture. Les contraintes industrielles qui ont guidé nos travaux nous ont orienté vers une approche par apparence, avec des hypothèses réduites afin que le système soit peu contraignant pour l'utilisateur. Les différentes étapes abordées concernent la détection de la main basée sur la couleur de peau, l'extraction de caractéristiques invariantes, la comparaison de descripteurs de forme pour la reconnaissance de postures 2D, et le suivi 3D du mouvement des doigts et de la main avec un modèle squelettique. Les algorithmes ont été évalués à l'aide d'une base originale de vidéos stéréoscopiques, montrant l'amélioration notable des solutions proposées. La robustesse du système a également été confrontée aux conditions réelles d'une démonstration publique.
202

Bacterial indicators for beach water quality /

Yau, Yick-yee, Joyce. January 1999 (has links)
Thesis (M. Sc.)--University of Hong Kong, 1999. / Includes bibliographical references.
203

Nonparametric tests to detect relationship between variables in the presence of heteroscedastic treatment effects

Tolos, Siti January 1900 (has links)
Doctor of Philosophy / Department of Statistics / Haiyan Wang / Statistical tools to detect nonlinear relationship between variables are commonly needed in various practices. The first part of the dissertation presents a test of independence between a response variable, either discrete or continuous, and a continuous covariate after adjusting for heteroscedastic treatment effects. The method first involves augmenting each pair of the data for all treatments with a fixed number of nearest neighbors as pseudo-replicates. A test statistic is then constructed by taking the difference of two quadratic forms. Using such differences eliminate the need to estimate any nonlinear regression function, reducing the computational time. Although using a fixed number of nearest neighbors poses significant difficulty in the inference compared to when the number of nearest neighbors goes to infinity, the parametric standardizing rate is obtained for the asymptotic distribution of the proposed test statistics. Numerical studies show that the new test procedure maintains the intended type I error rate and has robust power to detect nonlinear dependency in the presence of outliers. The second part of the dissertation discusses the theory and numerical studies for testing the nonparametric effects of no covariate-treatment interaction and no main covariate based on the decomposition of the conditional mean of regression function that is potentially nonlinear. A similar test was discussed in Wang and Akritas (2006) for the effects defined through the decomposition of the conditional distribution function, but with the number of pseudo-replicates going to infinity. Consequently, their test statistics have slow convergence rates and computational speeds. Both test limitations are overcome using new model and tests. The last part of the dissertation develops theory and numerical studies to test for no covariate-treatment interaction, no simple covariate and no main covariate effects for cases when the number of factor levels and the number of covariate values are large.
204

Jüngerschaft und Gemeinde: eine praktisch-theologische Studie uber die Erziehung zur Nachfolge in evangelikal-freikirchlichen Gemeinden im postmodern-urbanen Umfeld (Discipleship and the local church: a practical-theological study of education to discipleship in evangelical free churches in a postmodern urban milieu)

Hoffmann, Thomas 30 November 2005 (has links)
The subject of this study is Christian education in the church. This practical-theological work starts from the premise of the relevance of a commitment experience for the faith development of the individual and studies the formats and contents of continuing formal faith education of young Christians in evangelical free churches in a postmodern-urban milieu in Frankfurt. Its aim is to find out how well the New Testament discipleship topics of Jesus are integrated into the faith education in the church, and what reception difficulties and chances they experience in regard to the Zeitgeist. Are the New Testament discipleship topics still the basic guidelines with regard to content? The relationship between faith development, faith education and the local church is presented within a religion- and church-pedagogical approach and a connection to education for discipleship is made. The biblical premise is the discipleship commission of Jesus (Mt 28:18-20) and its church-pedagogical reply. / Der Untersuchungsgegenstand ist die christliche Erziehung in der Gemeinde. Diese praktisch-theologische Arbeit geht aus von der Bedeutung einer Commitment-Erfahrung für die Glaubensentwicklung des Einzelnen und untersucht die Formate und Inhalte der weiterführenden formalen Glaubenserziehung junger Christen in evangelikal-freikirchlichen Gemeinden im postmodern-urbanen Umfeld in Frankfurt. Ihr Ziel ist es, herauszufinden, inwiefern heute die neutestamentlichen Nachfolgethemen Jesu in der gemeindlichen Glaubenserziehung behandelt werden und welche Rezeptionsschwierigkeiten und Chancen sie im heutigen Zeitgeist haben. Sind dabei die neutestamentlichen Nachfolgethemen Jesu noch die inhaltlichen Grundrichtlinien? In einem religions- und gemeindepädagogischen Zugang wird die Beziehung von Glaubensentwicklung, Glaubenserziehung und der Ortsgemeinde gezeigt und mit der Erziehung zur Nachfolge verknüpft. Der biblische Ausgangspunkt ist der Jüngerschaftsauftrag Jesu (Mt 28,18-20) und dessen gemeindepädagogische Antwort. / Practical Theology / M. Th.(Practical Theology)
205

Étude par sous-structuration des vibrations transmises au système main-bras des cyclistes

Perrier, Sébastien January 2014 (has links)
Depuis quelques années dans le domaine du cyclisme de route, le confort des vélos est devenu un élément au moins aussi recherché que la performance. Le confort est une préoccupation majeure pour 90 % des cyclistes. Les cyclistes sur route passionnés enfourchent leurs vélos pendant plusieurs centaines d’heures chaque année. Ils souhaitent donc utiliser un vélo qui aura la capacité de réduire les vibrations générées par la route. Un sondage réalisé auprès de 320 cyclistes a montré que les vibrations transmises au niveau de la main sont considérées comme la plus grande source d’inconfort. Ce travail a permis de développer une approche permettant d’estimer le niveau de vibrations transmis au niveau de la main du cycliste par sous-structuration. Les méthodes de sous-structuration permettent de prédire le comportement dynamique d’un assemblage de structures par caractérisation de chacune des structures prise séparément. Bien que ces méthodes existent depuis des dizaines d’années, aucune étude n’avait investigué l’assemblage de deux structures par sous-structuration lorsqu’une d’entre elles est l’Humain. L’approche proposée consiste à mesurer la réponse biodynamique du système main-bras en posture cycliste et à prédire la puissance vibratoire au niveau de la main du cycliste à l’aide d’une méthode de sous-structuration. Cette thèse présente les éléments importants issus de ces travaux. Deux méthodes de couplage ont été identifiées et testées pour prédire l’influence du système main-bras sur le comportement dynamique de structures mécaniques simples. La variabilité de réponse du système main-bras de plusieurs sujets a été analysée. Des caractéristiques communes à plusieurs sujets ont été identifiées dans la réponse biodynamique de leurs systèmes main-bras. Finalement, l’importance relative du cycliste par rapport au vélo sur le comportement dynamique de l’assemblage vélo – cycliste au niveau de la main a conduit au développement d’une méthode de caractérisation de la réponse vibratoire des vélos seuls.
206

L’Entente Québec-France et ses limites : le cas des médecins de famille

Dumas-Martin, Antoine January 2014 (has links)
Officiellement, l’Entente entre le Québec et la France en matière de reconnaissance mutuelle des qualifications professionnelles avait pour principal objectif de faciliter la mobilité de la main-d’œuvre qualifiée entre le Québec et la France. Nous avons essayé d’en apprécier l’impact pour une profession particulière : médecin spécialiste en médecine de famille. Nous constatons que l’Entente, étant donné l’objectif de facilitation de la mobilité, a eu une portée somme toute limitée. Cette limitation tient surtout au fait que l’Entente soit subordonnée aux dispositions législatives, règlementaires et administratives internes à chacune des Parties, soit la France et le Québec. C’est donc dire que les principales limites se situent non pas au niveau des relations internationales mais au niveau national.
207

Investigating the properties of brown dwarfs using intermediate-resolution spectroscopy

Canty, James Ignatius January 2015 (has links)
This thesis is an investigation into some properties of brown dwarfs using medium-resolution spectroscopy. In the first part of the thesis, I address the issue of parameter degeneracy in brown dwarfs. In the course of my analysis, I derive a gravity-sensitive spectral index which can be used, statistically at least, to differentiate populations of young objects from field dwarfs. The index is also capable of finding the difference between a population of ~1 Myr objects and a population of ~10 Myr objects and may be used to separate low-mass members from foreground and background objects in young clusters and associations. The second part of my thesis is an investigation into the major opacity sources in the atmospheres of late T dwarfs. I look particularly at CH4 and NH3 absorption features in the near-infrared spectra of these objects. In my analysis, I identify new absorption features produced by these molecules. I also correct features which had previously been wrongly identified. This has been made possible by the use of high quality data, together with a new CH4 synthetic line list, which is more complete at these temperatures than any previously available list.
208

Solution reactivity studies of group 15 Zintl anions towards unsaturated substrates

Turbervill, Robert S. P. January 2014 (has links)
This thesis describes selected reactivity studies of group 15 Zintl anion [E7]3– (E = P, As) derived cages towards a series of unsaturated organic molecules. The synthesis and characterization of forty-two compounds derived from [E7]3– cages are detailed herein. A high yielding procedure for the synthesis of [HE7]2– (E = P, As) from the K3E7 Zintl phase has been developed. This solves prior issues with poor solubility and variable purity of the Zintl phases. The conditions required for the deprotonation of the phosphorus congener to [P7]3– are described. The reactivity of both [P7]3– and [HP7]2– towards carbon dioxide and isolobal isocyanates and carbodiimides was explored. This yielded a series of monofunctionalized [E7R]2– cages, via a net hydropnictination of a C=N double bond of the organic substrate. The protonation chemistry of these anions was further investigated, resulting in the formation of the protic [HP7C(NHDipp)(NDipp)]– cluster. This anion is capable of further hydrophosphination chemistry to give a series of difunctionalized heptaphosphide cages. The reaction of [E7]3– with alkynes results in the formation of the relatively unusual 1,2,3-tripnictolide anions. A series of such anions have been prepared, encompassing all of the previously reported anions and several novel species. Investigation of the coordination properties of these cyclopentadienyl analogues shows that they are superior π acceptor ligands. A synthetic route to [P5]– as a compositionally pure solid, and some initial studies on its protonation chemistry are also additionally presented.
209

Synthesis and reactivity of transition metal-group 13 complexes

Riddlestone, Ian Martin January 2013 (has links)
The synthesis and reactivity of a number of mixed transition metal-aluminium and σ-alane complexes are detailed in this thesis. Chapter III reports on the formation and structural characterisation of N,N'-chelated aluminium dihalide precursors featuring amidinate and guanidinate substituents. These precursors of the type RC(R'N)<sub>2</sub>AlX<sub>2</sub> (R = <sup>i</sup>Pr<sub>2</sub>N or Ph; R' = Cy or <sup>i</sup>Pr or Dipp; X = hal), readily react with Na[CpFe(CO)<sub>2</sub>] via salt elimination to form the corresponding mixed iron-aluminium complexes CpFe(CO)2[(X)Al(NR')2CR] which have been characterised both spectroscopically and by X-ray diffraction. The reactivity of the novel mixed aluminium-iron complexes towards halide abstraction agents has been investigated and a propensity for augmented coordination at the aluminium centre observed. Furthermore, complementary syntheses of the methyl substituted complex CpFe(CO)<sub>2</sub>[(Me)Al(NCy)<sub>2</sub>CN<sup>i</sup>Pr<sub>2</sub>] have been developed. This can be achieved either via the reaction between the related chloride complex and MeLi, or from the reaction between <sup>i</sup>Pr<sub>2</sub>C(CyN)<sub>2</sub>Al(Me)Cl and Na[CpFe(CO)<sub>2</sub>]. The research detailed in Chapter IV builds on the previous chapter and is focussed on the use of more sterically demanding substituents at both aluminium and transition metal, as well as more electron rich transition metal fragments. The transition metal anions Na[Cp*Fe(CO)<sub>2</sub>] and Na[Cp<sup>Si</sup>Fe(CO)(PPh<sub>3</sub>)] react with the aluminium precursors forming related mixed iron-aluminium complexes which have been structurally characterised. The Dipp<sub>2</sub>NacNacAlCl<sub>2</sub> precursor has been shown to undergo reaction with both Na[CpFe(CO)<sub>2</sub>] and Na[Cp*Fe(CO)<sub>2</sub>]. The halide abstraction chemistry of the latter utilising both Lewis acid and salt metathesis based abstraction approaches has been investigated. The dehydrohalogenation chemistry of the Dipp<sub>2</sub>NacNacAlCl<sub>2</sub> precursor was investigated and the ligand activated products of reactions with both alkyl lithium and alkyl potassium reagents characterised. Chapter V reports the extension of salt metathesis for the formation of an Al-H-Mn interaction, and the product has been fully characterised. In addition, the coordination of Al-H bonds from a number of alane precursors to in situ generated 16-electron fragments has allowed the structural characterisation of a number of novel σ-alane complexes. The incorporation of the transition metal fragments [Cp'Mn(CO)<sub>2</sub>] and [W(CO)<sub>5</sub>] permit comparison to archetypal borane and silane σ-complexes. Quantum chemical calculations suggest that the alane ligand has a binding energy close to that of dihydrogen but significantly less than that of CO, consistent with a predominant σ-donor role of the Al-H bond. The formation and structural characterisation of the κ<sup>2</sup>-complexes (OC)<sub>4</sub>M[κ<sup>2</sup>-H<sub>2</sub>AlDipp<sub>2</sub>NacNac] (M = Cr, Mo or W) define an unprecedented binding motif for the alane ligand. In the cases of chromium and molybdenum the κ<sup>2</sup>-complexes can be prepared either photolytically or via alkene displacement from the corresponding (OC)<sub>4</sub>M(cod) reagent. In the case of tungsten the alkene displacement route yields the desired product, but only under more forcing conditions. Spectroscopic characterisation of the related κ<sup>1</sup>-complex (OC)<sub>5</sub>Cr[κ<sup>1</sup>-H<sub>2</sub>AlDipp<sub>2</sub>NacNac], which readily forms the κ<sup>2</sup>-complex in solution without photolysis, has enabled the kinetics of chelate ring closure to be investigated. This analysis further characterises the formation of the unprecedented κ<sup>2</sup>-binding motif for the alane ligand.
210

Supply chain management practices in construction and inter-organisational trust dynamics

Manu, Emmanuel January 2014 (has links)
The poor trust culture in the construction sector is often considered an inhibiting factor to collaboration success in the United Kingdom (UK) despite reform efforts. Numerous reform initiatives tend to have focused on improvements in client and main contractor aspects of construction supply chain relationships, prompting claims that failure to integrate subcontractors, suppliers and consultants into collaborative arrangements remains a major shortcoming. Main contractor and subcontractor relationships therefore continue to be typified by such problems as late payments, charging fees to tender for work, award of contracts based on cheapest price rather than best value, negative margins and demand of retrospective discounts and cash rebates; all of which negatively impact on trust. Some main contractor organisations however, continue to embed supply chain management practices as a strategy for levering value from subcontractors. Such collaborative practices and their implications for inter-organisational trust development, and indeed overall project outcomes, have nonetheless received limited attention in construction management research, raising significant questions on the empirical basis for their implementation. This research was thus undertaken to investigate strategic supply chain management practices adopted by UK main contractors and its implications for inter-organisational trust development during projects. The study adopts a multiple case study design so as to unravel complex subtleties of inter-organisational trust development in the main contractors’ supply chain during projects. With four purposefully selected UK main contractor organisations that had implemented strategic supply chain management, data was gathered through a supply chain workshop, semi-structured interviews, passive observations and documentary analysis. From analysis of the data, it was revealed that strategic supply chain management practices of the main contractors were instrumental for trust manifestation across cognition, system and relational based dimensions. These practices served as constitutive elements of face-to-face interactions through which inter-organisational trust developed, whilst providing the institutional framework to which respective supply chain parties directed their psychological expectations. These findings highlight the importance of maintaining a core of subcontractors from which the main contractor can leverage long-term value irrespective of economic climate. This can be achieved by adequately prioritizing relationally trusted subcontractors for sensitive and high risk work packages whilst ensuring that strategic supply chain management principles can be used to engender impersonal (cognition and system-based) trust dimensions amongst other subcontractors used on a project. Accordingly, a supply chain management oriented framework for engendering inter-organisational trust during projects has been developed based on the study findings and evaluated through semi-structured interviews with selected target participants. This framework does not only provide a systematic and coherent approach for implementing or benchmarking strategic supply chain management in a main contractor’s organisation, but can also be used to prioritize and promote different trust dimensions and their associated behavioural consequences on projects, depending on perceived work package risks.

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