Dissertations / Theses on the topic 'Bottom-up construction'

Specifically outlining the work achieved in this PhD thesis, the work is organised into separate articles that have been published, submitted or are under preparation for submission.
Chapter 1 is an introduction, in which the state of the art and objectives are presented.
In Chapters 2-4, different potential mediators that could be used for the catalytic interaction with the enzymatic product o-AP were evaluated and due to their well characterized properties, hydrazine, NADH and ascorbic acid were selected for further study. Hydrazine is used as an antioxidant and reducing agent; NADH plays an important rule in oxidoreductases and dehydrogenase systems and ascorbic acid (vitamin C) is an antioxidant whose detection is important in clinical and food applications. The electrocatalytic properties of o-aminophenol films grafted on glassy carbon surfaces have been employed for the electrochemical evaluation of hydrazine, NADH and ascorbic acid, to select the most relevant as a recycling mediator in the planned signal amplification strategy. To evaluate the best mediator, the reaction kinetics between mediators and the o-AP/o-QI were extensively studied using different techniques such as cyclic voltammetry, hydrodynamic voltammetry, double potential step chronoamperometry, and double potential step chronocoulometry.
Of them, ascorbic acid was selected as the mediator for regeneration of the o-AP film and substrate recycling. We had thus demonstrated an interesting catalytic system for the oxidation of ascorbic acid, which is stable, sensitive and reproducible, and we decided to explore this system for clinical and food applications. In the first application, we targeted the determination of uric acid (UA) in the presence of ascorbic acid (AA), which commonly co-exist in biological fluids of humans, mainly in blood and urine (Chapter 4). In Chapters 5 and 6, the selective electrocatalytic properties of the grafted o-AP film toward ascorbic acid were also applied to its detection in real samples of fruits and vegetables using disposable one-shot screen printed electrodes. The o-AP modified screen printed electrodes showed high catalytic responses toward the electrocatalytic oxidation of ascorbic acid. The o-AP SPE sensor exhibited high sensitivity and selectivity toward ascorbic acid with excellent storage and operational stability, as well as a quantitatively reproducible analytical performance.
In the second part of the thesis, different surface engineering strategies of antibody immobilization for immunosensor construction using a linker or via direct attachment onto a Au surface using a strategy of self assembly were evaluated and compared. An alternative strategy explored was the direct anchoring of the antibody with or without a linker via the electrochemical reduction of their diazonium cations.
In Chapter 7, a comparison between these different surface chemistries methodologies for the construction of immunosensors towards the model analyte of coeliac toxic gliadin was carried out. Firstly, the self-assembled monolayer approach was evaluated based on the modification of gold surfaces with two bipodal carboxylic acid terminated thiols (thioctic acid and a benzyl alcohol disubstituted thiol, DT2). A stable SAM of DT2 was rapidly immobilized (3 h) on Au as compared with thioctic acid (100 h), although both surface chemistries resulted in highly sensitive electrochemical immunosensors for gliadin detection using an anti-gliadin antibody (CDC5), with detection limits of 11.6 and 5.5 ng/mL, respectively. The developed immunosensors were then applied to the detection of gliadin in commercial gluten-free and gluten-containing food products, showing an excellent correlation when compared to results obtained with ELISA.
In Chapter 8, another approach was explored to further improve immunosensor sensitivity and stability and furthermore to reduce the time necessary for sensor preparation was investigated looking at the direct attachment of the SATA modified full length antibody, and their F(ab) fragments onto Au electrodes. Spontaneously adsorbed SAMs of Fab-SH and CDC5-SH onto Au were rapidly formed in less than 15 minutes. The amperometric immunosensors based on Fab fragments exhibited a vastly improved detection limit as compared to the thiolated antibody with a highly sensitive response toward gliadin detection (LOD, 3.29 ng/ml for amperometric detection and 0.42 g/ml for labelless (impedimetric) detection). Moreover, the self-assembled monolayer of F(ab) fragments was extremely stable with almost no loss in response after 60 days storage at 4oC.
In Chapter 9, an alternative surface chemistry approach was explored for the modification of Au electrodes via electrochemical and spontaneous reduction of diazonium cations of a conjugate prepared from the monoclonal full length anti-gliadin antibody (CDC5) and the linker 3,5-bis(aminophenoxy)benzoic acid (DAPBA). Cylic voltammetry was chosen for surface modification via applying three potential cycles, but it was observed that an extensive washing process was necessary after each potential cycle to remove the non-specifically adsorbed molecules or formed multilayers. The affinity of the immobilized antibody toward gliadin was studied using EIS and amperometry. The modified CDC5-DAPBA surface showed a reasonable amperometric response after incubation with 5 g/ml gliadin, and exhibited excellent specificity with no response observed in the absence of the analyte.
In Chapter 10, general conclusions and future work are presented.
From the different surface chemistry strategies evaluated in this work we can conclude that the best approach is the immunosensor based on the spontaneous adsorption of thiolated F(ab) fragments on gold. This surface is easy and fast to prepare, very stable and sensitive and can be stored for long times in the appropriate conditions without lost of affinity. A good alternative to this approach seems to be the electrodeposition of antibody-diazonium conjugates, although further work is needed in order to optimize this system.
Overall, this work has contributed significantly to the vision we have for an immunosensor that avoids washes and reagent addition, where we have selected an excellent mediator for co-encapsulation with alkaline phosphatase enzymes within liposome reporter molecules, for regeneration of surface immobilised substrate following enzymatic dephosporylation, facilitating substrate recycling and increase in sensitivity and reduction in detection limit. Furthermore, we have selected an optimum surface chemistry for co-immobilisation of capture antibody molecules and enzyme substrate via the formation of self-assembled monolayers of antibody fragments on gold surfaces. Future work will focus on combining the selected mediator and surface chemistry into a sandwich immunosensor with a target sensitive liposome reporter molecule, to demonstrate a reagentless, washless ultrasesensitive immunosensing platform.
El trabajo descrito en la presente tesis ha sido organizado en capitulos en los que se detallan diferentes artículos publicados, enviados para su publicación o en preparacion en los cuales esta basada la tesis.
El Capitulo 1 es una introducción en la que se presenta el estado del arte del tema y los objetivos de la tesis.
En los Capítulos 2 a 4 se evalúan las propiedades electrocatalíticas de diferentes mediadores (hidracina, NADH y ácido ascórbico) que podrían ser utilizados en reacciones de reciclado de substratos enzimáticos en estrategias de amplificación de señal en biosensores. La hidracina es usada como antioxidante y agente reductor, el NADH es fundamental para el funcionamiento de oxidorreductasas y deshidrogenasas y el ácido ascórbico (AA, vitamina C) es de gran importancia como antioxidante. Las propiedades electrocatalíticas de monocapas de o-aminofenol (o-AP) en superficies de carbón vítreo fueron empleadas en la caracterización electroquímica de estos mediadores con el objetivo de seleccionar el mediador más adecuado. Para ello se determinaron diferentes parámetros cinéticos asociados empleando voltametría cíclica e hidrodinámica, así como cronoamperometría y cronocoulometría de doble potencial, siendo el acido ascórbico es mas adecuado en términos de coste, respuesta electroquímica y estabilidad.
Teniendo en cuenta estas propiedades del AA, se decidió explorar otras posibles aplicaciones clínicas y en análisis de alimentos de este sistema. En primer lugar se estudio la determinación de acido úrico en presencia de AA, el cual coexiste en diferentes fluidos biológicos y se estudió su determinación en muestras reales de orina (Capítulo 4).
En los Capítulos 5 y 6 se detalla la utilización de electrodos desechables modificados con o-AP fabricados con la técnica de screen-printing en la determinación de AA de ácido ascórbico en una amplia variedad de frutas y vegetales frescos y zumos comerciales. La selectividad, reproducibilidad y estabilidad de estos electrodos fueron también estudiadas.
En la segunda parte de la tesis se evalúan diferentes estrategias para la inmovilización de anticuerpos para la construcción de inmunosensores. Estas estrategias consisten en la deposición de los anticuerpos en superficies de oro mediante autoensamblaje de compuestos tiolados o la electrodeposición de sales de diazonio.
En el Capítulo 7 se compara el uso de dos compuestos ditiolados para la modificación de superficies de oro. Estos compuestos se emplearon para la inmovilización de anticuerpos en la construcción de un inmunosensor electroquímico para la detección de gliadina en muestras reales.
El Capítulo 8 es la continuación del trabajo anterior y está basado en la adsorción espontánea de fragmentos de anticuerpos o anticuerpos tiolados en superficies de Au para la detección de gliadina. Para ello se compararon las respuestas amperométricas de ambos sistemas, observándose una excelente sensibilidad en el caso de los fragmentos de anticuerpos, asi como una mayor estabilidad (hasta 60 dias a 4ºC) de este sistema.
En el Capítulo 9, se estudia una alternativa consistente en la electrodeposición de sales de diazonio conjugadas a anticuerpos. Para ello se estudiaron diferentes métodos de deposicion (electroquímicos o adsorción espontánea), siendo la deposición empleando voltametría ciclica la más adecuada. Sin embargo, esta metodología requirió de un gran número de pasos de lavado para la eliminaciñon de compuestos adsorbidos no específicamente. A pesar de esto, el anticuerpo inmovilizado mostró una buena afinidad hacia la gliadina al ser evaluada por amperometría con una excelente especificidad.
El Capítulo 10 consiste en las conclusiones generales y un plan de trabajo para el futuro.
De forma general, este trabajo ha contribuido significativamente a la culminación de una estrategia que evita pasos de lavado y de adición de reactivo en el diseño de inmunosensores. Para ello se la seleccionado el mediador más adecuado para coencapsulación con fosfatasa alcalina en liposomas para la regeneración de sustratos inmovilizados en superficies, lo cual facilita su reciclado, así como incrementa la sensibilidad y disminuye los limites de detección. Paralelamente, se han estudiado diferentes superficies para la inmovilización de anticuerpos consistentes en la deposición de los anticuerpos y sus fragmentos en superficies de oro mediante autoensamblaje de compuestos tiolados o la electrodeposición de sales de diazonio. Se propone en el futuro combinar ambas estrategias en la construcción de plataformas inmunosensoras de fácil operatividad y ultrasensibles.

Although issues linked to global environmental change and its role within peace, conflict andsecurity have been subject to social and political controversy for years, they are still notsufficiently respected by energy companies, trade unions, national governments andinternational institutions alike. Through applying the tools of a single instrumental case studylinked to the application of discourse analysis I, this study explores the process of securitizationof the environment in the extraordinary case of the resistance and occupation surrounding theHambach Forest, thereby countering the widely held assumption that collective action aimedat radically changing existing structures is not possible. The particular exploratory focus is puton the way this non-conventional environmental security discourse has been created within aredefined securitization framework. By challenging the traditional focus of securitizationtheory on top-down construction through elites, this study provides a broadened, bottom-upaccount of environmental securitization stemming from local civil society actors as nonpowerholdersthat effectively proclaim their recognition of the environment’s intrinsic valuefrom a grassroots level. Consequently, it argues for the significance of securitization as creativeprocess of alerting policy makers, political leaders and the broader society to the emergency ofclimate change and global environmental degradation symbolized through the specific case ofHambach Forest.

The field of high-energy physics has been living a very exciting period of its history with the Large Hadron Collider (LHC) at CERN collecting data. Indeed, this enormous machine able to collide protons at a center of mass energy of 14 TeV promises to unveil the mystery around the physics at such energy scales. From the physicists side, the expectations are very strong as it isnowadays a certitude that the Standard Model of particle physics is incomplete and should, in fact, be interpreted as the effective theory of a more fundamental one. Unfortunately, the 7 and 8 TeV runs of the LHC did not provide any sign of new physics yet but there has been at least one major discovery in 2010, namely the discovery of a scalar particle with a mass of 125 GeV and whichproperties are very close to those of the Standard Model Higgs boson. Since then, many questions have come up as we now want to understand if it really is the Standard Model Higgs boson or if it exhibits any deviations. It is in this peculiar context that my research work was carried. In a first project, we, my supervisors, our collaborator and I, have wanted to explore thephenomenology associated with the neutralinos and charginos sector of the left-right symmetric supersymmetric model. Such an analysis can be motivated by several reasons such as the fact that the supersymmetric nature of these models provides a natural explanation for the infamous hierarchy problem, implies the unification of the gauge coupling constants at very high energy and provides a natural candidate for dark matter. In addition to these nice features, the left-right symmetry introduces a natural framework for explaining the smallness of neutrino masses but also helps in addressing several other unresolved issues in the Standard Model framework. Only focusing on the lightest charginos and neutralinos decaying into one or more light leptons, we have shown in our study that these models can be easily discovered in multi-leptonic final states as theylead to signatures very different from those induced by the Standard Model or its supersymmetric version.[...]

La thèse répond à deux problématiques, d'une part la quantification des effacements de consommation d'électricité par technologies gaz dans l'habitat et d'autre part de l'intégration de leurs valorisations dans une perspective de planification des infrastructures. Ces travaux se justifient dans un contexte d'augmentation de la pointe électrique, à l'origine d'une hausse du risque de défaillance du système, et de la baisse des consommations de gaz naturel conduisant à une sous utilisation du réseau de distribution. Pourtant, alors que la demande en gaz naturel croît du fait de l'installation de centrales à cycle combiné sur le réseau de transport, l'interaction des réseaux de distribution gaz/électricité n'est pas exploitée.Ce manuscrit envisage l'intégration des technologies gaz comme moyen de Maîtrise de la Demande en Électricité dans le processus de planification des réseaux. Ainsi les effacements de consommations d'électricité lors des périodes dimensionnantes par des micro-cogénérateurs ou des chaudières hybrides sont des solutions alternatives aux solutions de renforcement de réseaux.Pour quantifier le gisement d'effacement, nous nous intéressons à l'impact marginal des systèmes sur la demande en termes de modification de la quantité d'Énergie Non Distribuée potentielle. Les estimations des impacts de systèmes de chauffage sur la demande sont donc des prérequis à cette approche. Nous modélisons les courbes de charge régionales par une approche Bottom-Up permettant de déterminer les profils de demande marginale de chauffage en fonction des systèmes. La mise en application de cette méthode est à fiabiliser par des études socio-technico-économiques permettant de réduire les incertitudes sur les déterminants des besoins de chauffage. Une calibration en puissance des profils générés a été proposée mais n'a pu être réalisée. En revanche, nous apportons une contribution à l'analyse des courbes de charge agrégées en montrant que le modèle d'estimation actuellement utilisé par le gestionnaire de réseau s'apparente à un modèle simplifié de bâtiment
This PhD thesis addresses two issues: Firstly, the assessment of Demand Side Management (DSM) opportunity of gas and electricity technologies in dwellings, and secondly, the integration of their valuations in infrastructure planning schemes.This work originaites from a context of the growth of electricity peaks (which increased risk of system failure) and the natural gas consumption decrease which leads to an under-utilization of the gas distribution network.This manuscript focuses on the integration of gas technologies as DSM solution to contribute to the planning of electricity grid. Indeed, relieving the electricity consumption during constrained periods by diffusing micro-cogeneration or hybrid boiler, is an actual alternative to network reinforcement solutions. To quantify the load shedding capacity, we are interested in the marginal impact of demand systems on the amount of Energy Not Supplied potential. Estimating systems' impacts on heating demand is a prerequisite to this approach. So we model the regional heating load curves by a Bottom-Up approach to simulate marginal demand profiles depending on heating systems. The implementation of this method requires socio-technico-economic studies to reduce uncertainty of the determinants of heating needs. A load calibration methodology has been proposed but has not been performed. However, we make a contribution to the analysis of aggregated load curves emphasizing that the load model currently used by network operator similar to a simplified building model

La thèse répond à deux problématiques, d'une part la quantification des effacements de consommation d'électricité par technologies gaz dans l'habitat et d'autre part de l'intégration de leurs valorisations dans une perspective de planification des infrastructures. Ces travaux se justifient dans un contexte d'augmentation de la pointe électrique, à l'origine d'une hausse du risque de défaillance du système, et de la baisse des consommations de gaz naturel conduisant à une sous utilisation du réseau de distribution. Pourtant, alors que la demande en gaz naturel croît du fait de l'installation de centrales à cycle combiné sur le réseau de transport, l'interaction des réseaux de distribution gaz/électricité n'est pas exploitée.Ce manuscrit envisage l'intégration des technologies gaz comme moyen de Maîtrise de la Demande en Électricité dans le processus de planification des réseaux. Ainsi les effacements de consommations d'électricité lors des périodes dimensionnantes par des micro-cogénérateurs ou des chaudières hybrides sont des solutions alternatives aux solutions de renforcement de réseaux.Pour quantifier le gisement d'effacement, nous nous intéressons à l'impact marginal des systèmes sur la demande en termes de modification de la quantité d'Énergie Non Distribuée potentielle. Les estimations des impacts de systèmes de chauffage sur la demande sont donc des prérequis à cette approche. Nous modélisons les courbes de charge régionales par une approche Bottom-Up permettant de déterminer les profils de demande marginale de chauffage en fonction des systèmes. La mise en application de cette méthode est à fiabiliser par des études socio-technico-économiques permettant de réduire les incertitudes sur les déterminants des besoins de chauffage. Une calibration en puissance des profils générés a été proposée mais n'a pu être réalisée. En revanche, nous apportons une contribution à l'analyse des courbes de charge agrégées en montrant que le modèle d'estimation actuellement utilisé par le gestionnaire de réseau s'apparente à un modèle simplifié de bâtiment

Le mémoire vise à proposer une épistémologie pragmatique de la science scolaire à l’école primaire. Un défaut de compréhension de la nature de la science pourrait en effet justifier en partie les difficultés de l'enseignement des sciences par démarche d'investigation. Une étude des représentations de la science chez les enseignants et futurs enseignants confirme qu’ils n‘en ont pour la plupart qu‘une vision assez floue, relevant majoritairement d'une forme d'empirisme naïf. Un jeu opératoire de critères de scientificité adapté au contexte de l’école est développé dans une approche "bottom-up" partant des pratiques de classe effectives. Sa capacité à discriminer pratiques scientifiques et non scientifiques est discutée, de même que les implications didactiques et épistémologiques de son utilisation. Il est en particulier possible d‘en déduire des définitions évolutives d‘une science scolaire normative mais subsidiaire par rapport à la “science des scientifiques”. Cet outil épistémologique s’avère bien reçu par les enseignants auxquels il a été présenté. Le test en situation de différentes stratégies pédagogiques fait apparaître que les plus efficaces pour l'appropriation de critères de scientificité ajoutent à la démarche d’investigation une composante épistémologique explicite. Certains éléments de méthode scientifique peuvent être travaillés dès la Grande Section de maternelle (5-6 ans) : des élèves ayant vécu des démarches d’investigation s’avèrent capables de revendiquer la primauté de l’expérience, mais aussi de mettre en œuvre des tests relatifs à plusieurs critères de scientificité et de s‘approprier les rudiments de la modélisation scientifique
The purpose of this thesis is to propose a pragmatic epistemology of school science in primary school. Indeed, some of the difficulties encountered by inquiry-based science education may be attributed to a lack of understanding of the very nature of science. A survey on the perception of science by incumbent teachers and teachers in training confirms that most of them have a relatively vague vision grounded in a form of naive empiricism. A practical set of criteria of scientificity adapted to the school context is developed through a “bottom-up” approach based on actual classroom practices. Its efficiency at discriminating scientific and non-scientific practices is discussed, as well as the didactical and epistemological implications of its use. It is thus possible to deduce evolutive definitions of a school science that is normative yet subordinated to the “science of scientists”. Teachers responded positively to this epistemological tool when it was presented to them. Among the different teaching strategies tested in a classroom, the most efficient for the acquisition of criteria of scientificity were those which supplemented the inquiry process with an explicit epistemological component. Some elements of scientific method can be introduced as early as kindergarten (5-6 y.o) : after experimenting with inquiry processes, pupils have proved able not only to claim the primacy of experiment but also to run tests related to different criteria of scientificity and acquire the basics of scientific modeling

This dissertation concerns itself with the problem of constructing multi asset class portfolios. The investment process is aimed at solving two problems. The first problem is estimating the future returns of individual securities, which is an exercise fraught with uncertainty as the future is fundamentally unpredictable. This uncertainty means that the investor must allocate his portfolio to a number of assets instead of just one, in case his predicted future returns do not materialize. This leads the investor to the second problem of how best to construct the portfolio. It is this part of the investment process which is the subject of this dissertation which examines whether it is best to construct multi-asset class portfolios using a top-down or bottom-up approach. In the top-down approach one begins by creating independent single asset class portfolios which are then combined to create a multi-asset class portfolio. The bottom-up approach constructs the portfolio by considering all the securities available to the investor (irrespective of asset class) at the same time. The Mean-Variance and Black- Litterman models are reviewed in detail. Portfolios are then created using these portfolio construction methods in order to compare the two approaches. In constructing these portfolios, the commonly encountered problem of missing data in financial return series is also examined. The main result is that the top-down and bottom-up approaches create similar efficient frontiers, though the bottom-up approach results in an extended frontier which allows investors to obtain efficient portfolios with either a higher expected return or a lower volatility.

This work presents mainly two contributions to Description Logics (DLs) research by means of Formal Concept Analysis (FCA) methods: supporting bottom-up construction of DL knowledge bases, and completing DL knowledge bases. Its contribution to FCA research is on the computational complexity of computing generators of closed sets.

This work presents mainly two contributions to Description Logics (DLs) research by means of Formal Concept Analysis (FCA) methods: supporting bottom-up construction of DL knowledge bases, and completing DL knowledge bases. Its contribution to FCA research is on the computational complexity of computing generators of closed sets.

Cette recherche se déroule auprès des personnels au sol et de leur encadrant dans une compagnie aérienne. Elle vise à rendre compte, dans une approche ergonomique, des processus de fragilisation ou de construction des parcours de travail de ces salariés dans un contexte de transformations multiples et continues (digitalisation de la relation de service des agents de service au client, flexibilités interne et externe des équipes de bagagistes, vieillissement démographique d’ensemble, etc.). Cette thèse poursuit l’hypothèse que le travail des régulateurs (encadrant de premier niveau en charge de l’affectation des tâches sur les plannings des personnels au sol) est médiateur dans la construction des relations santé/travail des personnels au sol en étant vecteur de parcours-usure ou de parcours-construction. Elle mobilise des outils méthodologiques propres à la démographie du travail et à l’ergonomie de l’activité, en combinant des approches diachronique (mise au jour de temporalités multiples ayant des dimensions individuelle, collective et gestionnaire) et synchronique (articulation ou tension entre ces temporalités dans l’activité). Les résultats révèlent la multiplicité des indicateurs de santé et leurs temporalités que mobilisent les régulateurs pour organiser le travail, les stratégies de prévention individuelles et collectives élaborées au fil de leur expérience et le rôle des contraintes temporelles dans les possibilités de les mettre en œuvre
This research is carried out with ground staff and their supervisors in an airline company. It aims to report, from an ergonomic approach, on weakening or construction’s processes of these employees’ work paths in a context of multiple and continuous transformations (digitalization of the service relationship of customer service agents, internal and external flexibility of baggage handler teams, overall demographic ageing, etc.). This thesis pursues the hypothesis that the work of regulators (firstlevel managers in charge of assigning tasks to ground staff schedules) mediates the construction of health/work relations between ground staff by being a vector of the path wear and tear or path construction. It mobilizes methodological tools specific to the demography of work and the ergonomics of the activity, by combining diachronic (revealing multiple temporalities with individual, collective and managerial dimensions) and synchronic (articulation or tension between these temporalities in the activity) approaches. The results reveal the multiplicity of health indicators and their temporalities mobilized by regulators to organize work, the individual and collective prevention strategies developed in the course of their experience and the role of temporal constraints in the possibilities of implementing them

In the face of knowledge deficits in and poor outcome assessments of Organisation Transformation (OT), there is a need for a better understanding of the relationship between change leader interventions and qualitative organisational schema change, the collective knowledge structures that must be replaced or significantly elaborated if OT is to be realised. Previous research on this relationship has (a) focused on imposed structural interventions and given little attention to large-scale human process interventions, (b) given little attention to the radical structural interventions frequently involved in the transformation of public organisations, (c) given little scrutiny to how organisational schema have been conceptualised, (d) given little scrutiny to recent propositions on schema change dynamics that may be contentious, and (e) given little consideration to the change management contexts in which leader influence may be neutralised. In the light of these gaps in the literature, this thesis investigates, from the perspective of change recipients, the relationship between complex large-scale change leader interventions and qualitative organisational schema change in change management contexts thought to be inimical to leader influence. In particular, how efficacious are change leader interventions in realising qualitative organisational schema change in such contexts? An interpretive longitudinal case study design was used to address this question. The case organisation is a spatially differentiated technically-oriented public Professional Bureaucracy located in Queensland. In this context, this thesis investigates, over a three-year period, the creation and evolution of three schema change contexts, or change trajectories, created by two temporally disconnected yet functionally inter-related change leader interventions. Data collection techniques included focus group interviews, semi-structured interviews, and secondary sources. Data were collected from several sites, including Head Office functions and Regional and District offices, across Queensland. Data were collected on four occasions across the three-year period from early 2000 to late 2002. The results reveal that (a) while there are no panaceas, public managers need more sophisticated intervention theories based on a knowledge of the relative efficacy of different interventions rather than relying on, predominantly, structural interventions, (b) viewing organisational schema in one-dimensional rather than multidimensional terms masks both the complexity of organisational schema change and the possibility of partial rather than configurational schema change, (c) while inter-schema conflict or dialectical processes were apparent, successful schema change was better explained by teleological processes than by dialectical processes, and (d) change leaders can have a powerful influence on OT in change management contexts thought to be inimical to change leader influence yet their influence is linked to high investments of time and effort.

L'objectif de la thèse est de fournir les méthodes qui permettent de gérer au mieux l'énergie en assurant le confort souhaité. Les modèles de charges sont développés et validés par des mesures. La prévision à court-terme de la consommation correspondant aux multi bâtiments (région) et au secteur résidentiel est proposée par réseaux de neurones et la méthode ascendante. Trois méthodes originales de la gestion optimale prédictive des chauffages et des climatisations sont développées: optimisation du confort thermique, minimisation des pics et minimisation des coûts de consommation. Deux méthodes originales de la gestion des charges en temps réel sont proposées: méthode basée sur un système de régulation adaptative des chauffages et des climatisations et méthode basée sur le délestage en fonction de la courbe de protection. Les méthodes proposées sont validées par simulation pour une maison (secteur résidentiel) et un hôtel (secteur tertiaire) avec les résultats satisfaisants.

碩士
萬能科技大學
影像顯示技術研究所
100
Texts in images often draw people’s attention because they often convey semantic meaning for objects (e.g., the title of a book), information on an environment (e.g., a traffic sign), or a commercial purpose (e.g., an advertisement). With the improvement of embedded system devices and communication technologies, most smart phones equip cameras. A system incorporated with text detection and Optical Character Recognition (OCR) techniques provides a convenient, flexible, and intuitive approach for users to gather useful information. Today, mobile applications with text detection techniques for natural scenes can assist people. To ensure the quality of OCR output, the successful obtainment of single character in digital images is the fundamental pre-procedure. This thesis proposed a text detection system in natural scenes. The system detects texts and estimates the corresponding text-lines in a single image. Because the orientation of text-lines in natural scenes may not always be horizontal, this work proposes a two-stage bottom-up framework for extracting the orientation of text-lines. Stroke information in images is first extracted using an image operator called the Stroke Width Transform (SWT). Afterwards, text candidates are extracted according to the stroke information. Text candidates are connected one another to form text-line according to certain rules. Combining the proposed text detection system and OCR can provide users an automatic text recognition application on smart phones.

碩士
東吳大學
資訊管理學系
98
Connected Dominating Sets (CDS) construction is a well known strategy to form a virtual backbone in wireless multi-hop networks. In broadcasting tasks, CDS as a virtual backbone can help to broadcast message easily and prevent the broadcast storm. Moreover, in order to reduce the communication overhead and prolong the network lifetime, it is desirable to find a CDS of small CDS size, diameter, and Average Backbone Path Length (ABPL).Currently, the researches about constructing quality CDS in terms of size, diameter, and ABPL, is a kind of top-down approach CDS construction. However, this top-down approach CDS construction incurs the redundant dominators. Thus, we propose a bottom-up approach CDS construction which can construct CDS effectively. Simulation results show that our algorithm can find the better quality CDS in terms of size, diameter, and ABPL.