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Manipulations électroniquement induites de molécules individuelles à la surface de semiconducteurs : vers les dispositifs bi-moléculaires / Electronically induced manipulation of single molecules adsorbed on semiconductor surfaces : towards bi-molecular devicesLabidi, Hatem 26 October 2012 (has links)
L’objectif de cette thèse est d’explorer le contrôle de processus électroniquement induits dans diverses molécules fonctionnalisées adsorbées sur la surface du Si(100). Ce travail s’inscrit dans le contexte des nanosciences moléculaires et a été réalisé à l’aide d’un microscope à effet tunnel (STM) à basse température (9K). Nous avons utilisé une approche combinant étude statistique et modélisation théorique afin de pouvoir explorer la physique des divers processus observés. Cette thèse débute par l’étude de la molécule d’hexaphényle benzène (HPB) dont les phényles latéraux permettent un découplage électronique entre la molécule et la surface du silicium. Grâce à cet effet, nous avons pu contrôler la diffusion directive et réversible de la molécule d’HPB physisorbée le long des marches de type SA à la surface du Si(100)−2×1 à travers un processus combinant l’action des électrons tunnels et celle du champ électrostatique induit par la pointe du STM. Ces premiers résultats ont permis d’envisager l’étude d’un couple de molécules de tétraphényles porphyrines métalliques adsorbées à la surface du Si(100)−2×1. Il s’agit de NiTPP et de CuTPP qui, comme pour l’HPB, possèdent des cycles phényles latéraux. Plusieurs conformations d’adsorption de ces deux molécules ont été caractérisées et leurs réponses à des excitations électroniques étudiées. Ceci nous a permis, pour la molécule de NiTPP, d’aboutir au contrôle de l’activation réversible d’un bistable intra-moléculaire en dépit de la chimisorption partielle de la molécule sur le silicium. L’étude de la molécule de CuTPP, quant à elle, montre des courbes de conductance I(V) en forme d’hystérésis associées à des changements réversibles de conformations réalisant ainsi une fonction mémoire. Dès lors, nous avons pu étudier la co-adsorption des molécules de NiTPP et de CuTPP sur le Si(100) afin de réaliser un binôme moléculaire. Divers couples de molécules ont pu être étudiés. Sur l’un d’entre eux, nous avons pu activer des processus d’excitations inter-moléculaires en excitant électroniquement l’une des molécules afin d’observer un changement de conformation de la seconde molécule du binôme. Ce résultat réalise ainsi le contrôle électronique d’un dispositif bi-moléculaire en s’affranchissant des processus électroniques induits via le substrat. Enfin, à titre de perspective, ce travail de thèse présente un procédé novateur permettant le contrôle local de l’hydrogénation de la surface de Si(100). Ceci est réalisé grâce à la passivation de la pointe du STM par l’hydrogène moléculaire à 9K. Les électrons tunnels sont ensuite utilisés pour induire la dissociation intra-dimer des molécules d’H2 sur la surface du Si(100). Cette technique peut être envisagée pour la passivation du Si(100) ou pour agir localement sur des circuits moléculaires. / The objective of this thesis is to explore the control of electronically induced processes in various functionalized molecules adsorbed on the surface of silicon (100). In the context of molecular nanoscience, this work has been carried out using a scanning tunneling microscope operating at low temperature (9K). We used an approach combining statistical study and theoretical modelling in order to explore the physics of the various observed processes. This thesis begins with the study of the Hexaphenylbenzene (HPB) molecule for which the lateral phenyl rings enable the molecule-silicon surface electronic decoupling. Thanks to this effect, we could achieve a directive and reversible diffusion control of physisorbed HPB molecules along the SA silicon step edge through a process combining the joint actions of tunnel electrons and the local STM tip induced electrostatic field. These first results allowed considering the study of a couple of metaltetraphenyl porphyrin molecules adsorbed on the Si(100)-2x1 surface. Similarly to the HPB molecules, the two chosen metalloporphyrins: NiTPP and CuTPP, have lateral phenyl rings. Several adsorption conformations for these molecules were characterized and their response to electronic excitation has been studied. In the case of NiTPP, this led to the control of the reversible activation of an intra-molecular bistable despite the partial chemisorption of the molecule on the silicon surface. As for CuTPP molecule, our study revealed hysteresis behavior on the I(V) conduction curves associated with reversible conformation changes which represents the realization of a memory function. Following the study of each molecule apart, we performed the co-adsorption of the two molecules on the Si(100) surface to study molecular pairs. Various pairs of molecules have been studied. On one of them, we were able to activate an inter-molecular excitation transfer process by locally exciting one molecule and observing a conformation change of the second molecule of the pair. This result thus shows the electronic control of a bi-molecular device getting rid of substrate mediated electronic process. Finally, as a perspective, this thesis presents a novel technique allowing the controlled local hydrogenation of the Si(100) surface. This is achieved thanks to the passivation of the STM tip by molecular hydrogen at 9K. The tunnel electrons are then used to induce the intra-dimer dissociative adsorption of H2 molecules on the Si(100) surface. This technique could be considered for the passivation of Si(100) or to locally modify molecular circuits.
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Potentialité de préparation de revêtements céramiques par projection plasma sous basse pression / New preparation of ceramic coatings by low-pressure plasma spraySong, Chen 25 June 2018 (has links)
En tant que technologie de projection thermique avancée, la projection plasma sous basse pression (LPPS) permet d'obtenir des revêtements de haute qualité et peut combler l'écart d'épaisseur entre les technologies de projection thermique conventionnelles et les procédés de couche mince standard. En outre, LPPS permet de construire des revêtements uniformes avec diverses microstructures; le dépôt a lieu non seulement à partir des éclaboussures liquides, mais aussi à partir des amas nanométriques ainsi que de la phase vapeur en fonction des conditions opérationnelles. Afin de continuer à améliorer et à développer le procédé LPPS, cette recherche vise à le combiner avec les procédés émergents de projection plasma en suspension et de projection plasma réactif. Il devait à la fois fournir deux nouveaux processus intégrés et réaliser des revêtements à structure fine avec des microstructures uniques et des performances élevées.Une torche à plasma bi-cathode (laboratoire LERMPS, UTBM, France) à mode d'injection axiale a été conçue et construite pour le LPPS, dont la puissance maximale en entrée du plasma a pu atteindre 80 kW. En utilisant cette nouvelle torche, soit la suspension à très fines particules, soit les poudres micrométriques ont pu être injectées dans le centre du plasma à basse pression. En conséquence, le transfert de chaleur et de masse entre le jet de plasma et les matériaux pulvérisés a été amélioré.La torche à plasma bi-cathode axiale a été appliquée d'abord pour pulvériser deux types de charges de YSZ, y compris la suspension de YSZ et les poudres agglomérées de YSZ. Les résultats ont indiqué que tous les revêtements YSZ présentaient des structures relativement denses en raison de la grande vitesse des particules sous faibles pressions. Les revêtements ont été composés des particules fondues, des particules agglomérées ainsi que du dépôt en phase vapeur. Il a été constaté que le degré de vaporisation de YSZ a été augmenté en utilisant une taille de particule plus fine, une pression ambiante plus basse, une distance de pulvérisation plus longue et une puissance de plasma plus élevée. En outre, tous les revêtements YSZ ont subi une transformation de phase significative d'une phase monoclinique à une phase tétragonale, et le degré de transformation était proportionnel au degré de vaporisation. Cependant, les propriétés mécaniques des revêtements résultants ont des comportements opposés. Les revêtements YSZ préparés à partir des particules agglomérées, qui avaient une plus grande taille de gouttelettes et moins de dépôt en phase vapeur, présentaient une dureté et un module de Young plus élevés que les revêtements YSZ fabriqués à partir d'une suspension fine.Une autre torche à plasma à haute énergie O3CP (Oerlikon Metco, Suisse) a été utilisée pour synthétiser in situ les revêtements de TiN sur des alliages de Ti-6Al-4V par projection de plasma réactive à très basse pression. Les poudres de Ti pur ont été pulvérisées dans une atmosphère de N2 sous une puissance de plasma d'entrée de 120 kW. Les revêtements TiN hybrides structurés ont été synthétisés, ce qui n'était pas le cas auparavant avec d'autres procédés de projection thermique. Il est connu que la réaction de nitruration se produisait non seulement dans le jet de plasma mais aussi sur le substrat. De plus, avec l'augmentation de la distance de pulvérisation, l'effet de nitruration a été affaibli et la structure hybride du revêtement de TiN a changé de laminaire dense en colonne poreuse, en function du degré de vaporisation supérieur, de la concentration de réactive inférieure et du substrat plus froid.. Néanmoins, ils ont également permis d'améliorer les propriétés mécaniques du substrat Ti-6Al-4V. / As an advanced thermal spray technology, low-pressure plasma spray (LPPS) allows obtaining high-quality coatings and can bridge the thickness gap between conventional thermal spray technologies and standard thin film processes. Moreover, LPPS permits to build uniform coatings with various microstructures; deposition takes place not only from liquid splats but also from nano-sized clusters as well as from the vapor phase depending on operational conditions. In order to further improve and develop the LPPS process, this research aims to combine it with the emerging suspension plasma spray and reactive plasma spray processes. It was expected to both provide two novel integrated processes and achieve fine-structured coatings with unique microstructures and high performance.A bi-cathode plasma torch (LERMPS lab, UTBM, France) with an axial injection mode was designed and built for LPPS, whose maximum input plasma power was able to reach to 80 kW. By using this new torch, either the very fine-particle suspension or the micro-sized powders was able to be injected into the plasma center under low pressures. As a result, the heat and mass transfer between the plasma jet and the sprayed materials were enhanced.The axial bi-cathode plasma torch was applied firstly to spray two kinds of YSZ feedstocks, including the YSZ suspension and the YSZ agglomerated powders. The results indicated that all the YSZ coatings exhibited relatively dense structures due to the high velocity of particles under low pressures. The coatings were composed of the melted particles, the agglomerated particles as well as the vapor deposition. It was found that the vaporization degree of YSZ was increased by using smaller particle size, lower ambient pressure, longer spraying distance and higher plasma power. In addition, all the YSZ coatings undergone a significant phase transformation from a monoclinic phase to a tetragonal phase, and the transformation degree was proportional to the vaporization degree. However, the mechanical properties of the resulting coatings had the opposite behaviors. The YSZ coatings prepared from the agglomerated particles, which had a bigger droplet size and less vapor deposition, showed a higher hardness and Young's modulus than the YSZ coatings fabricated from fine suspension did.Another high-energy plasma torch O3CP (Oerlikon Metco, Switzerland) was employed to in-situ synthesize the TiN coatings on Ti-6Al-4V alloys by reactive plasma spray under very low pressure. The pure Ti powders were sprayed into an N2 atmosphere under an input plasma power of 120 kW. The hybrid structured TiN coatings were synthesized, which was not previously achieved with other thermal spraying processes. It was known that the nitriding reaction occurred not only in the plasma jet but also on the substrate. Additionally, with increasing spraying distance, the nitriding effect was weakened, and the hybrid structure of TiN coating changed from dense laminar to porous columnar, according to the higher vaporization degree, lower reactant concentration and colder substrate. Nevertheless, they also were able to improve the mechanical properties of the Ti-6Al-4V substrate.
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Development of Elicitation Methods for Managerial Decision SupportRiabacke, Ari January 2007 (has links)
Decision‐makers in organisations and businesses make numerous decisions every day, and these decisions are expected to be based on facts and carried out in a rational manner. However, most decisions are not based on precise information or careful analysis due to several reasons. People are, e.g., unable to behave rationally as a result of their experiences, socialisation, and additionally, because humans possess fairly limited capacities for processing information in an objective manner. In order to circumvent this human incapacity to handle decision situations in a rational manner, especially those involving risk and uncertainty, a widespread suggestion, at least in managerial decision making, is to take advantage of support in the form of decision support systems. One possibility involves decision analytical tools, but they are, almost without exception, not efficiently employed in organisations and businesses. It appears that one reason for this is the high demands the tools place on the decision‐maker in a variety of ways, e.g., by presupposing that reliable input data is obtainable by an exogenous process. Even though the reliability of current decision analytic tools is highly dependent on the quality of the input data, they rarely contain methods for eliciting data from the users. The problem focused on in this thesis is the unavailability and inefficiency of methods for eliciting decision information from the users. The aim is to identify problem areas regarding the elicitation of decision data in real decision making processes, and to propose elicitation methods that take people’s natural choice strategies and natural behaviour into account. In this effort, we have identified a conceptual gap between the decision‐makers, the decision models, and the decision analytical tools, consisting of seven gap components. The gap components are of three main categories (of which elicitation is one). In order to study elicitation problems, a number of empirical studies, involving more than 400 subjects in total, have been carried out in Sweden and Brazil. An iterative research approach has been adopted and a combination of quantitative and qualitative methods has been used. Findings made in this thesis include the fact that decision‐makers have serious problems in many decision situations due to not having access to accurate and relevant data in the first place, and secondly, not having the means for retrieving such data in a proper manner, i.e. lacking elicitation methods for this purpose. Employing traditional elicitation methods in this realm yield results that reveal an inertia gap, i.e. an intrinsic inertia in people’s natural behaviour to shift between differently framed prospects, and different groups of decisionmakers displaying different choice patterns. Since existing elicitation methods are unable to deal with the inertia, we propose a class of methods to take advantage of this natural behaviour, and also suggest a representation for the elicited information. An important element in the proposed class of methods is also that we must be able to fine‐tune methods and measuring instruments in order to fit into different types of decision situations, user groups, and choice behaviours.
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BIOMA : En modell för att bedöma en organisations BI-mognad ur ett multidimensionellt perspektiv / BIOMA: Business Intelligence Organizational Maturity Analysis : A Model for measure organizational BI-maturity through amultidimensional perspectiveWidehammar, Per, Langell, Robin January 2010 (has links)
Den ökade globaliseringen och senaste finanskrisen ställer höga krav på uppföljning och medvetenhet av ett företags prestation. Business Intelligence (BI) är ett område vars syfte är att förbättra en organisations prestation genom analys av historisk data. BI är ett komplext område som inte bara handlar om tekniska lösningar, även om det är en förutsättning. För närvarande investeras det mycket i olika BI-lösningar och företagen behöver veta vad resurserna bör läggas på. I dagsläget finns det ingen modell som bedömer ett företags arbete med Business Intelligence utifrån ett flertal dimensioner. Syftet med den här studien var att utveckla en mognadsmodell för Business Intelligence och sedan jämföra de undersökta företagen Axfood, Scania och Systembolagets mognad. För att uppnå studiens syfte avsåg vi att besvara följande frågeställningar, ”Hur skulle en modell för att bedöma ett företags mognad inom Business Intelligence kunna se ut?” samt ”Vilka förutsättningar påverkar ett företags mognad inom Business Intelligence”. Mognadsmodellen (BIOMA) kom att bestå av fyra hörnstenar som i sin tur delades in i en eller flera underkategorier. Varje delkategori ger poäng som sedan infogas i ett koordinatsystem där axlarna motsvarar hörnstenarna och poängen utgår från origo. Att mäta ett företags mognad inom BI är komplext, då ett antal aspekter såsom organisationsstruktur, användarmedverkan samt klyftan mellan IT-avdelning och verksamhet kan påverka. Den teoretiska modellen är empiriskt testad. Respondenterna på respektive företag har bedömt hur långt de kommit inom varje hörnsten samt ge synpunkter på modellens utformning. Modellen har sedan förädlats utifrån det empiriska materialet. Vi anser att BIOMA har ett stort värde då det saknas en modell som visuellt och relativt enkelt beskriver ett företags mognad inom Business Intelligence. Modellen kan användas i olika syften, såsom benchmarking mellan processer och företag, säljstöd för konsulter samt vid förstudie för att klargöra ett företags nuläge. / The increased globalization and the recent financial crisis have put high demands on the monitoring and awareness of an organization's performance. Business Intelligence (BI) is an area which aims to improve this performance through analysis of historical data. BI is a complex question for organization’s because it involves more than just technical solutions for maximum performance. Organizations are currently investing in different BI solutions and a list of priorities has to be made to ensure balanced resource allocation within a BI-implementation. To this day no single business intelligence model exists that can adequately measure a company’s work from several perspectives. The purpose of this study was to develop a maturity model for BI and use it in a case study of three different well-known Swedish companies; Axfood, Scania and Systembolaget, to measure their BI-maturity. To achieve the purpose of the study, three distinct research questions arose; "What would a model for measuring a company’s Business Intelligence maturity look like? How would this model be constructed? And finally “What conditions could potentially affect an organization’s maturity in Business Intelligence?". The Maturity Model BIOMA (Business Intelligence Organizational Maturity Analysis) is made up of four categories, which in turn are divided into one or more sub-categories. A subcategory consists of several statements. Each statement carries a certain number of points. When the points are combined, the summarized amount is inserted into a coordinate system. Within this, the axies correspond to the pillars and the score is based on the origo-point. Measuring a company's BI-maturity is a complex research question, where a number of aspects such as organizational structure, end-user involvement, and the gap between IT department and business can be of great importance. BIOMA was empirically tested in the case study. The responders in each company judged their company based on the statements in each subcategory. Following this they made suggestions on ways to change the model. By applying these suggestions to the original material, the model was then redeveloped to create a final version. The model can be used for various purposes, such as processes within organizations or in benchmarking. It can also be used by consultants in Sales support as a pilot study for clarifying a company’s present BI-maturity. In this absence of a model that could visually describe a company’s BI maturity multidimensionally, we believe that BIOMA has substantial and existing business potential.
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In vitro-Versuche mit dem Polo like-Kinase 1 Hemmstoff BI 2536 an Zelllinien von GallenwegskarzinomenThrum, Stephan 25 February 2014 (has links) (PDF)
Karzinome der Gallenwege sind mit einer schlechten Prognose assoziiert. Eine potentiell kurative chirurgische Resektion ist bei der Mehrzahl der Patienten aufgrund des späten Zeitpunkts der Diagnosestellung nicht möglich, so dass derzeit vorrangig palliative Therapieansätze Anwendung finden. Das nur geringe Ansprechen auf konventionelle Radio- oder Zytostatikatherapie begründet die Notwendigkeit neuer Therapieansätze. Einen möglichen Angriffspunkt stellt hierbei die Polo-like-Kinase 1 (Plk1) dar, da ihre zentrale Rolle in der Regulation des Zellzyklus zunehmend erkannt und eine vermehrte Expression in malignem Tumorgewebe verglichen mit gesundem Gewebe nachgewiesen wurde. Das Dihydropteridinon BI 2536 ist ein poten-ter, niedermolekularer und selektiver Hemmstoff der Plk1 und sollte daher auf seine Wirksamkeit an Gallenwegskarzinomen untersucht werden.
In der vorliegenden Arbeit konnte gezeigt werden, dass BI 2536 die untersuchten 14 Zelllinien von Gallenblasen- und Gallengangskarzinomen wirkungsvoll hemmt. Das Ansprechen unterschied sich zwischen den Zelllinien und ordnet sich vergleichbar zu Veröffentlichungen an anderen malignen Tumoren ein. Die Expression von Plk1 und dessen assoziierten Transkriptionsfaktor FoxM1 konnte bei Westernblot-Versuchen bei allen Zelllinien nachgewiesen werden, was eine Bedeutung in der Onkogenese vermuten lässt. Die Behandlung mit BI 2536 beeinflusste jedoch die Proteinmenge beider nicht. An für die folgenden Versuche ausgewählten drei Zelllinien zeigten sich in der reversen Transkription mit anschließender Echtzeit-Polymerase-Kettenreaktion (qRT PCR) ähnliche Ergebnisse in Bezug auf die exprimierte mRNA von Plk1. Westernblot-Analysen ermittelten keine signifikanten Veränderungen der an wichtigen intrazellulären Kaskaden beteiligten Proteine p42/44 und Akt sowie deren phosphorylierten Formen. Obwohl die Proteinmenge des Mitosemarkers Phospho-Histon H3 ebenso unverändert blieb, führte die Behandlung mit BI 2536 – dies zeigen Ergebnisse der Durchflusszytometrie – zu einer signifikanten, dosisabhängigen Zunahme der G2/M Fraktion des Zellzyklus und Zunahme der Apoptose-rate. Der maximale Hemmeffekt in der Behandlung von BI 2536 lag bei einer Inkubations-dauer von vier Tagen.
Die Empfehlungen aus den klinischen Studien der Phase II von BI 2536 sowie dem Ziel der Vermeidung von Resistenzen ergibt sich die Notwendigkeit von Kombinationsversuchen mit Zytostatika, die in einer anderen Phase des Zellzyklus angreifen. Die in der Behandlung von Gallenwegskarzinomen etablierten Antimetaboliten 5-Fluorouracil und Gemcitabin wurden hierzu ausgewählt und es zeigten sich für 5 Fluorouracil synergistische, für Gemcitabin hingegen additive Kombinationseffekte. Zusätzlich wurde die Wechselwirkung mit dem IGF 1-Rezeptor-Inhibitor NVP-AEW541 untersucht, der ebenfalls einen neuen Behand-lungsansatz in der Krebstherapie darstellt und bei Gallenwegskarzinomen in vitro wirksam ist. Auch hier zeigen sich synergistische Effekte, die jedoch erst in höheren Behandlungs-dosen auftraten.
Die Ergebnisse dieser Arbeit zeigen, dass die Hemmung der Plk1 bei Gallenblasen- und Gallengangskarzinomen einen wirksamen Behandlungsansatz darstellt. Auf der Grundlage der in dieser Arbeit beschriebenen Ergebnisse wird eine weitere präklinische und klinische Testung von selektiven Plk1-Hemmstoffen wie BI 2536 an Gallenwegskarzinomen empfohlen.
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Planejamento da expansão de sistemas de transmissão considerando análise de confiabilidade e incertezas na demanda futuraGarcés Negrete, Lina Paola [UNESP] 25 February 2010 (has links) (PDF)
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garcesnegrete_lpg_dr_ilha.pdf: 1723635 bytes, checksum: ec9b369023c0d16cf9bcbe29a4bc0ada (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Nessa pesquisa tem-se por objetivo a análise teórica e a implementação computacional de duas propostas de solução ao problema de planejamento da expansão de sistemas de transmissão de energia elétrica considerando diferentes fatores relacionados com a confiabilidade do sistema e a adoção dos novos modelos de mercados elétricos. É importante notar, que no planejamento básico não são levados em conta esses importantes aspectos. Dessa forma, uma primeira aproximação considera um critério de confiabilidade para expandir o sistema, de forma que ele opere adequadamente no horizonte de planejamento satisfazendo um nível de confiabilidade pré-definido. O índice de confiabilidade utilizado para exigir esse nível de confiabilidade é o LOLE, que corresponde ao número médio de horas/dias em um período dado (normalmente um ano) no qual o pico da carga horária/diária do sistema possivelmente exceder´a a capacidade de geração disponível. O problema de planejamento considerando a confiabilidade é, portanto, formulado como um problema de otimização que minimiza o investimento sujeito ao critério de confiabilidade. O índice de confiabilidade para o sistema de transmissão é calculado para cada configuração, subtraindo o índice de confiabilidade do sistema de geração do sistema composto geração-transmissão (bulk power system ). Para calcular o índice no sistema composto geração transmissão, utiliza-se uma curva de duração de carga efetiva para este sistema. Esta curva acumulada de carga é obtida de um processo de convolução de outras duas curvas que representam a função de distribuição de probabilidade (FDP) das saídas aleatórias dos componentes do sistema e a curva de duração de carga, respectivamente. A avaliação de confiabilidade no sistema de geração é feita usando um método que calcula o índice de confiabilidade por meio dos momentos... / This work aims to the theoretical analysis and computational implementation of two proposals for the transmission expansion planning problem considering several factors such as system reliability and new electricity market structures. It is important to observe, that the basic planning does not consider these issues. Therefore, one first approach considers a reliability criterion to expand the system, so that it operates in adequate conditions in the horizon planning while satisfying pre-defined limits in the reliability index. Transmission system reliability criterion regards to LOLE, which refers to the number of hours/days in a specified period of time (normally one year), in which the hourly/daily peak load possibly will exceed the available generation capacity. So, the planning problem considering reliability is formulated as an optimization problem that minimizes the investment subject to probabilistic reliability criterion. Reliability index for the transmission system is calculated for each configuration by subtraction of generation and bulk power reliability indexes. A composite power system effective load curve is used for reliability analysis of the bulk power system. This accumulate curve is obtained convolving two curves, one of them corresponding to a probability distribution function of the random outages of the system components, and the other one corresponding to the load duration curve. Reliability assessment in the generation system is done using a method that calculates the reliability index through the statistics moments of the frequency distribution of equivalents loads. This curve is obtained by convolving the generation units which are dispached in merit order. The proposed model is solved using the specialized genetic algorithm of Chu-Beasley (AGCB). Detailed results on two test systems are analyzed and discussed. A second approach to the transmission expansion... (Complete abstract click electronic access below)
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Lecture de livres bilingues par six duos parent-enfant allophones du préscolaire : description des lectures et des interactions et relations avec l’acquisition du vocabulaireGosselin-Lavoie, Catherine 06 1900 (has links)
No description available.
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A data management and analytic model for business intelligence applicationsBanda, Misheck 05 1900 (has links)
Most organisations use several data management and business intelligence solutions which are on-premise and, or cloud-based to manage and analyse their constantly growing business data. Challenges faced by organisations nowadays include, but are not limited to growth limitations, big data, inadequate analytics, computing, and data storage capabilities. Although these organisations are able to generate reports and dashboards for decision-making in most cases, effective use of their business data and an appropriate business intelligence solution could achieve and retain informed decision-making and allow competitive reaction to the dynamic external environment. A data management and analytic model has been proposed on which organisations could rely for decisive guidance when planning to procure and implement a unified business intelligence solution. To achieve a sound model, literature was reviewed by extensively studying business intelligence in general, and exploring and developing various deployment models and architectures consisting of naïve, on-premise, and cloud-based which revealed their benefits and challenges. The outcome of the literature review was the development of a hybrid business intelligence model and the accompanying architecture as the main contribution to the study.In order to assess the state of business intelligence utilisation, and to validate and improve the proposed architecture, two case studies targeting users and experts were conducted using quantitative and qualitative approaches. The case studies found and established that a decision to procure and implement a successful business intelligence solution is based on a number of crucial elements, such as, applications, devices, tools, business intelligence services, data management and infrastructure. The findings further recognised that the proposed hybrid architecture is the solution for managing complex organisations with serious data challenges. / Computing / M. Sc. (Computing)
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Receptor scavenger BI: efeito de polimorfismos e atorvastatina na expressão gênica em indivíduos hipercolesterolêmicos / Scavenger receptor class BI: polymorphisms and atorvastatin effects on gene expression in hypercholesterolemic individualsÁlvaro Danilo Cerda Maureira 20 May 2009 (has links)
O receptor scavenger classe B tipo I (SR-BI) media a captação seletiva do colesterol da lipoproteina de alta densidade (HDL) e participa no effluxo do colesterol livre para aceptores lipoprotéicos. A HDL tem um importante rol aterogênico associado com sua participação no transporte reverso do colesterol. Polimorfismos no gene que codifica para o SR-BI (SCARB1) foram relacionados com alterações do perfil lipídico sérico e outros fatores de risco associados com doença cardiovascular. As estatinas são inibidores da síntese do colesterol utilizados no tratamento da dislipidemia. Vários polimorfismos em genes envolvidos no metabolismo intermediario de lipideos foram relacionados com diferenças na resposta a hipolipemiantes. Com a finalidade de avaliar o efeito de polimorfismos do SCARB1 sobre o perfil lipídico sérico, expressão gênica e a resposta a estatinas, foram selecionados 185 indivíduos normolipidêmicos (NL) e 147 pacientes hipercolesterolêmicos (HC). Os pacientes HC foram tratados com atorvastatina (10 mg/dia/4 semanas). DNA e RNA foram extraídos de amostras de sangue periférico. Os polimorfismos de nucleotídeo único (SNP) G4A, In5C>T e Ex8C>T foram detectados por PCR-RFLP. A expressão de RNAm do SCARB1 em células mononucleares de sangue periférico (CMSP) foi analisada por PCR em tempo real usando o gene da Ubiquitina c (UBC) como referência endógena. Nos indivíduos HC, as freqüências dos alelos raros G4A (12%), In5C>T (7%) e Ex8C>T (40%), no grupo HC, foram similares às encontradas no grupo NL (4A: 15%, In5T: 7%, e Ex8T: 35%, p>0,05). O alelo SCARB1 4A (genótipos GA + AA) foi associado com valores diminuídos de apoAI no grupo NL. O alelo In5T foi associado com maior concentração LDL-C sérico (p=0,029), em NL, e com apoB e razão apoB/apoAI elevadas (p>0,05) no grupo HC. O SNP SCARB1 Ex8C>T não foi relacionado com o perfil lipídico sérico basal, embora os portadores do genótipo Ex8CC foram associados com resposta reduzida ao tratamento com atorvastatina mostrando menor variação de colesterol total, LDL-C, apoB e razão apoB/apoAI. O SNP Ex8C>T foi associado com maior probabilidade (OR=3,1; 95% IC: 1,00-9,5; p=0,044) de ter uma resposta à atorvastatina diminuída. Os SNPs SCARB1 In5C>T e Ex8C>T estão em desequilíbrio de ligação. O haplótipo G1C5C8/G1T5C8 foi associado com concentrações basais elevadas de triglicérides e VLDL-C em NL e diminuídas de HDL-C e apoAI em HC. Os haplótipos G1C5C8/A1C5C8 e C5C8/C5C8 tiveram variação diminuída da apoB quando comparados com os outros haplótipos, G1C5C8/A1C5C8 e o diplótipo C5C8/C5C8 também apresentou uma variação reduzida da razão apoB/apoAI. Os SNPs G4A e In5C>T estão associados com diminuição da expressão gênica do SCARB1 em NL. O tratamento com atorvastatina não modifica a expressão de RNAm do SCARB1 em CMSP nos HC. Esses resultados são sugestivos de que os polimorfismos no SCARB1 estão associados com valores basais do perfil lipídico sérico e de expressão de RNAm do SCARB1, assim como de resposta à atorvastatina. / The scavenger receptor class B type I (SR-BI) mediates the selective uptake of the high density lipoprotein (HDL) cholesterol and it participates in the free cholesterol efflux to lipoprotein acceptors. HDL has an important antiatherogenic role associated with important activity in the cholesterol reverse transport. Polymorphisms in the SR-BI gene (SCARB1) have been related to variations on plasma lipoprotein profile and other risk factors for cardiovascular disease. Statins are potent inhibitors of cholesterol synthesis prescribed for treatment of the dislipidemia. Several polymorphisms in genes involved in intermediary metabolism of lipids have been related to differences in response to lowering-cholesterol drugs. In order to evaluate the effect of SCARB1 polymorphisms on serum lipids, gene expression and lipid-lowering response to atorvastatin, 185 normolipidemic (NL) and 147 hypercholesterolemic (HC) individuals were selected. HC individuals were treated with atorvastatin (10 mg/day/4 weeks). DNA and RNA were extracted from peripheric blood mononuclear cells (PBMC). SCARB1 mRNA expression was analyzed by real time PCR using ubiquitin c gene (UBC) as endogenous reference. The frequencies of the rare alleles in HC group (G4A: 12%; In5C>T: 7%, and ExC>T: 39%) were similar to those found in NL individuals (4A: 15%, In5T: 7%, and Ex8T: 35%, p>0.05). The SCARB1 4A allele (GA+AA genotypes) was associated with lower apoAI concentration in NL. The In5T allele was associated with higher serum LDL-C (p=0,029) in NL individuals, and with higher apoB and apoB/apoAI ratio (p>0,05) in HC group. SCARB1 Ex8C>T SNP was not related to serum lipids profile, however Ex8CC genotype carriers had lower variation of total cholesterol, LDL-C, apoB and apoB/apoAI ratio in response to atorvastatin. SCARB1 Ex8C>T was associated with higher chance to have a lower atorvastatin response (OR=3.1, 95% CI: 1.00-9.5; p=0.044). SCARB1 In5C>T and ExC>T were in linkage disequilibrium. G1C5C8/G1T5C8 SCARB1 haplotype was associated with higher level of triglycerides and VLDL-C in NL and lower HDL-C and apoAI levels in HC individuals. G1C5C8/A1C5C8 haplotype and C5C8/C5C8 diplotype had lower variations on apoB than the other haplotypes, and G1C5C8/A1C5C8 had also lower variation on apoB/apoAI ratio. G4A and In5C>T SNPs are associated with lower SCARB1 mRNA expression in PBMC of NL individuals. Atorvastatin therapy did not modify the expression level of the SCARB1 transcript in HC. Our results suggest that SCARB1 polymorphisms are associated with basal serum lipids profile, mRNA SCARB1 expression and atorvastatin response.
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Geovisualização analítica: desenvolvimento de um protótipo de um sistema analítico de informações para a gestão da coleta seletiva de resíduos urbanos recicláveis. / Analytical geovisualization: development of a prototype of an analytical information system for the management of the selective collection of recycled urban solid waste.Carlos Enrique Hernández Simões 16 April 2010 (has links)
Os resíduos urbanos descartados de forma irregular constituem um problema sério, principalmente nas grandes cidades, causando entupimento de bueiros e drenagem com conseqüentes inundações, sujeira e transmissão de doenças tais como leptospirose e dengue além de ser um estorvo para o trânsito e acarretarem gastos para a Prefeitura. Por outro lado, reciclar este material é uma fonte de receitas e um gerador de empregos. A Geovisualização Analítica pode ser de grande auxílio para a análise desse problema complexo e para a tomada de decisão. Com essa motivação, a presente dissertação procura fornecer uma visão geral sobre o estado da arte quanto a conceitos e pesquisas em Geovisualização (GVis) e Processamento Analítico (OLAP e SOLAP). Apresenta também processos, metodologias e tecnologias que foram utilizadas no desenvolvimento de um protótipo de um sistema analítico de informações aplicado à área de gestão da coleta seletiva de resíduos sólidos recicláveis em ambiente urbano. Este protótipo, efetivamente implantado, combinou navegação e consulta para recuperar informações através de seleções espaciais e alfanuméricas. Através de exemplos foi mostrado que este tipo de solução auxilia gestores nos processos de exploração, análise e tomada de decisão. / Domestic waste illegally disposed constitute a serious problem, especially in large cities, causing clogging of drains and drainage with subsequent flooding, dirt and transmission of diseases such as leptospirosis and dengue as well as being a hindrance to traffic and would entail city hall costs. Moreover, recycle this material is a source of revenue and a generator of jobs. The Analytical Geovisualization can be of great help in the analysis of this complex problem and the decision-making. With this motivation, this paper seeks to provide an overview of the state of the art as the concepts and research in Geovisualization (GVis) and Analytical Processing (OLAP and SOLAP). It also presents processes, methodologies and technologies that were used in developing a prototype of an analytical system applied to the area of selective collection information management of recyclable solid waste in urban environments. This prototype, effectively deployed, combined navigation and query to retrieve information through spatial and alphanumeric selections. Through examples it was shown that this type of solution helps managers in operating procedures, analysis and decision making.
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