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Defesa da concorrência e bem-estar do consumidor / Competition defense and consumer welfareRoberto Augusto Castellanos Pfeiffer 11 June 2010 (has links)
O objeto da tese de doutorado é a análise da relação entre a defesa da concorrência e a proteção do consumidor, duas políticas públicas que proporcionam benefícios mútuos e devem ser executadas de modo harmônico, havendo substrato normativo e teórico para incluir a preocupação com o bem-estar do consumidor como um dos objetivos da política de defesa da concorrência. No Brasil tal harmonização é uma imposição constitucional, já que a livre concorrência, a repressão ao abuso do poder econômico e a defesa do consumidor são princípios conformadores da ordem econômica. É defendida a utilização de um conceito unificado de consumidor, sendo adotada a teoria finalista, que o define como o destinatário final econômico do bem ou serviço. As duas políticas utilizam diferentes instrumentos e perspectivas na tutela do bem-estar do consumidor, o que fica claro na proteção do direito de escolha. O Código de Defesa do Consumidor oferece a isonomia como remédio para compensar a vulnerabilidade, estabelecendo regras destinadas à uma escolha consciente, sobretudo o direito à informação adequada e veraz. Já as normas de defesa da concorrência resguardam a liberdade preocupando-se em preservar a possibilidade de escolha entre mais de um fornecedor de produtos ou serviços. O exemplo mais contundente dá-se no controle de estruturas: a atuação das autoridades responsáveis pela análise dos atos de concentração é vinculada à preservação do excedente do consumidor e das condições imprescindíveis ao exercício do direito de escolha, sendo vedada a aprovação de fusões que prejudiquem o bemestar do consumidor. No âmbito repressivo a harmonização das duas políticas é intensificada com a colaboração entre as autoridades de defesa da concorrência e de proteção do consumidor para a fiscalização de condutas que configurem, ao mesmo tempo, infrações contra a ordem econômica e práticas abusivas, cuja dupla capitulação não acarreta bis in idem, pois são distintas as esferas jurídicas tuteladas, havendo assim diversidade de fundamentos. É salientada a importância das ações coletivas para reparação de danos causados aos consumidores por infrações contra a ordem econômica e defendida a adoção dos danos multiplicados e a manutenção da destinação dos valores arrecadados por multas a infrações contra a ordem econômica ao Fundo Federal de Direitos Difusos. / The thesis analyzes the relationship between the competition defense and the consumer protection, both public policies that offer mutual benefits and must be carried out in a harmonic way. So, there is a normative and theoretical substratum concerning the consumer welfare as one of the objectives of the antitrust policy. In Brazil such harmonization is imposed by the Constitution, since the free competition, the repression of the abuse of the economic power and the consumer protection are principles that pertain to the constitutional economic order. In this paper consumer is regarded as a unified concept, i.e., the economic final user of goods or services. Both policies use different instruments and perspectives for the protection of the consumer welfare, what is clear in the enforcement of the right of choice. The Consumer Defense Code refers to the isonomy as a remedy to make up for the vulnerability, establishing rules for a conscious choice, especially the right to the proper, true and accurate information. The antitrust rules are concerned with the freedom of choice and the possibilities of option from more than one supplier of products or services. The most outstanding example is related to the merger control: the antitrust authorities are required to guarantee a consumer surplus and the necessary conditions to exercise the right of choice, being totally banned the approval of mergers that may be harmful to the consumer welfare. The harmonization of both policies in the repression scope is intensified with the cooperation between antitrust and consumer protection authorities regarding to the law enforcement against practices that may represent infractions of the competition and of the consumer protection rules, as well. The thesis emphasizes the importance of class actions to repair consumer damages caused by antitrust law violations and defends the adoption of the multiplied damages and the maintenance of the allocation to the Diffuse Rights Federal Fund of amounts raised by fines collected by the Antitrust Authorities.
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有效匯率預測模型與避險績效比較 / Effective Exchange Rate Forecasting Models and Comparison Hedging Performance尤保傑 Unknown Date (has links)
本研究提出UIP、PPP、 MF、TR及TRa五種匯率預測模型,以新台幣兌美元即期匯率、遠期匯率進行避險準確率及避險成效的實證分析。資料期間為1996年12月到2012年10月的新台幣兌美元即期匯率月資料,資料來源為資料庫Datastream。
實證結果發現UIP、PPP、 MF、TR及TRa五種匯率預測模型比較分析中,若以相對購買力平價模型(PPP)進行選擇性避險,再搭配適當避險比率,其報酬率可能由負報酬轉為正報酬;避險績效衡量方面,以相對購買力平價模型搭配完全避險的績效最好。若以不對稱泰勒模型(TRa)進行選擇性避險,再搭配適當避險比率,報酬率明顯由負轉為正;衡量避險績效衡量方面,完全避險在風險降幅及下方動差避險績效衡量下,以不對稱泰勒模型搭配完全避險的績效最好。 / This study provides five exchange rate models to predict future exchange rate (UIP,PPP,MF,Taylor rule and asymmetric Taylor rule). We illustrate these methods by assessing the forecasting performance of five exchange rate models using monthly returns on TWD/US dollar exchange rate. The data are monthly exchange rates ranging from December 1996 to October 2012, using spot and one-month forward exchange rates form Datastream.
We find that empirical models based on purchase power parity (PPP) and the asymmetric Taylor rule(TRa) outperform the other models in out-of-sample forecasting using the appropriate hedging ratio. Comparing the hedging performance between PPP and models, we find that the hedging performance by the PPP will get the higher return. However, the hedging performance by the will get the lower volatility.
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Συμβολή στην ανάλυση του ηλεκτρικού και του μαγνητικού πεδίου στο περιβάλλον εναερίων γραμμών ηλεκτρικής ενέργειαςΤζινευράκης, Αντώνιος 22 December 2009 (has links)
Η παρούσα διδακτορική διατριβή αποτελεί μια συμβολή στην ανάλυση του ηλεκτρικού πεδίου στο περιβάλλον εναέριων γραμμών απλού και διπλού κυκλώματος. Αναπτύσσονται αναλυτικές σχέσεις για τον ακριβή υπολογισμό της έντασης του ηλεκτρικού πεδίου καθώς και απλούστερες προσεγγιστικές σχέσεις. Η προτεινόμενη μέθοδος υπολογισμού προέκυψε από τον συνδυασμό της ανάλυσης των φορτίων των αγωγών σε συμμετρικές συνιστώσες, της περιγραφής της έντασης του ηλεκτρικού πεδίου με διπλούς μιγαδικούς αριθμούς και της χρήσης του αναπτύγματος πολυπόλων για την έκφραση της έντασης του ηλεκτρικού πεδίου. Με τους διπλούς μιγαδικούς αριθμούς επιτυγχάνεται η παράσταση με μιγαδικούς αριθμούς τόσο των χρονικά ημιτονοειδώς μεταβαλλόμενων μεγεθών (τάσεων και φορτίων) όσο και των γεωμετρικών αποστάσεων. Το ανάπτυγμα πολυπόλων είναι μια σειρά απείρων όρων, όπου ο κάθε επόμενος όρος είναι αντιστρόφως ανάλογος της αυξανόμενης δύναμης της απόστασης. Αναπτύσσονται επίσης ακριβείς αναλυτικές σχέσεις, καθώς και απλούστερες προσεγγιστικές σχέσεις, για τον υπολογισμό της μαγνητικής επαγωγής γραμμών διπλού κυκλώματος. Για την ανάπτυξη των σχέσεων αυτών συνδυάζεται η χρήση των διπλών μιγαδικών αριθμών με το ανάπτυγμα πολυπόλων για την έκφραση της μαγνητικής επαγωγής. / This thesis is a contribution to the analysis of the electric field in the vicinity of single-circuit and double-circuit overhead power lines. Analytical formulas are developed for the accurate calculation of the intensity of the electric field as well as simpler approximate formulas. The proposed calculation method has arisen from the combination of the analysis of the conductors’ charges in their symmetrical components, the description of the intensity of the electric field using double complex numbers and the use of multipole expansions to express the intensity of the electric field. The use of double complex numbers allows the simultaneous representation of sinusoidal varying quantities (voltages and charges) and geometrical distances with complex numbers. The multipole expansion is a series of infinite terms, where each term is inversely proportional to an increasing power of the distance. Accurate analytical formulas are also developed as well as simpler approximate formulas for the calculation of the magnetic flux density produced by double-circuit lines. For the development of those formulas the use of double complex numbers is combined with the multipole expansion to express the magnetic flux density.
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Stratégies de guidage visuel bio-inspirées : application à la stabilisation visuelle d’un micro-drone et à la poursuite de cibles / Strategies for bio-inspired visual guidance : application to control an UAV and to track a targetManecy, Augustin 22 July 2015 (has links)
Les insectes sont capables de prouesses remarquables lorsqu’il s’agit d’éviter des obstacles,voler en environnement perturbé ou poursuivre une cible. Cela laisse penser que leurs capacités de traitement, aussi minimalistes soient-elles, sont parfaitement optimisées pour le vol. A cela s’ajoute des mécanismes raffinés, comme la stabilisation de la vision par rapport au corps, permettant d’améliorer encore plus leurs capacités de vol.Ces travaux de thèse présentent l’élaboration d’un micro drone de type quadrirotor, qui ressemble fortement à un insecte sur le plan perceptif (vibration rétinienne) et reprend des points structurels clés, tels que le découplage mécanique entre le corps et le système visuel. La conception du quadrirotor (de type open-source), son pilotage automatique et son système occulo-moteur sont minutieusement détaillés.Des traitements adaptés permettent, malgré un très faible nombre de pixels (24 pixels seulement), de poursuivre finement du regard une cible en mouvement. A partir de là, nous avons élaboré des stratégies basées sur le pilotage par le regard, pour stabiliser le robot en vol stationnaire, à l’aplomb d’une cible et asservir sa position ; et ce, en se passant d’une partie des capteurs habituellement utilisés en aéronautique tels que les magnétomètres et les accéléromètres. Le quadrirotor décolle, se déplace et atterrit de façon autonome en utilisant seulement ses gyromètres, son système visuel original mimant l’oeil d’un insecte et une mesure de son altitude. Toutes les expérimentations ont été validées dans une arène de vol, équipée de caméras VICON.Enfin, nous décrivons une nouvelle toolbox qui permet d’exécuter en temps réel des modèles Matlab/Simulink sur des calculateurs Linux embarqués de façon complètement automatisée (http://www.gipsalab.fr/projet/RT-MaG/). Cette solution permet d’écrire les modèles, de les simuler, d’élaborer des lois de contrôle pour enfin, piloter en temps réel, le robot sous l’environnement Simulink. Cela réduit considérablement le "time-to-flight" et offre une grande flexibilité (possibilité de superviser l’ensemble des données de vol, de modifier en temps réel les paramètres des contrôleurs, etc.). / Insects, like hoverflies are able of outstanding performances to avoid obstacles, reject disturbances and hover or track a target with great accuracy. These means that fast sensory motor reflexes are at work, even if they are minimalist, they are perfectly optimized for the flapping flight at insect scale. Additional refined mechanisms, like gaze stabilization relative to the body, allow to increase their flight capacity.In this PhD thesis, we present the design of a quadrotor, which is highly similar to an insect in terms of perception (visual system) and implements a bio-inspired gaze control system through the mechanical decoupling between the body and the visual system. The design of the quadrotor (open-source), itspilot and its decoupled eye are thoroughly detailed. New visual processing algorithms make it possible to faithfully track a moving target, in spite of a very limited number of pixels (only 24 pixels). Using this efficient gaze stabilization, we developed new strategies to stabilize the robot above a target and finely control its position relative to the target. These new strategies do not need classical aeronautic sensors like accelerometers and magnetometers. As a result, the quadrotor is able to take off, move and land automatically using only its embedded rate-gyros, its insect-like eye, and an altitude measurement. All these experiments were validated in a flying arena equipped with a VICON system. Finally, we describe a new toolbox, called RT-MaG toolbox, which generate automatically a real-time standalone application for Linux systems from a Matlab/Simulink model (http://www.gipsalab.fr/projet/RT-MaG/). These make it possible to simulate, design control laws and monitor the robot’s flight in real-time using only Matlab/Simulink. As a result, the "time-to-flight" is considerably reduced and the final application is highly reconfigurable (real-time monitoring, parameter tuning, etc.).
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Construction and analysis of compact residual discretizations for conservation laws on unstructured meshesRicchiuto, Mario 21 June 2005 (has links)
This thesis presents the construction, the analysis and the verication of compact residual discretizations for the solution of conservation laws on unstructured meshes. <p>The schemes considered belong to the class of residual distribution (RD) or fluctuation splitting (FS) schemes. <p>The methodology presented relies on three main elements: design of compact linear first-order stable schemes for linear hyperbolic PDEs, a positivity preserving procedure mapping stable first-order linear schemes onto nonlinear second-order schemes with non-oscillatory shock capturing capabilities, and a conservative formulation enabling to extend the schemes to nonlinear CLs. These three design steps, and the underlying theoretical tools, are discussed in depth. The nonlinear RD schemes resulting from this construction are tested on a large set of problems involving the solution of scalar models, and systems of CLs. This extensive verification fills the gaps left open, where no theoretical analysis is possible. <p>Numerical results are presented on the Euler equations of a perfect gas, on a two-phase flow model with highly nonlinear thermodynamics, and on the shallow-water equations. <p>On irregular grids, the schemes proposed yield quite accurate and stable solutions even on very difficult computations. Direct comparisone show that these results are more accurate than the ones given by FV and WENO schemes. Moreover, our schemes have a compact nearest-neighbor stencil. This encourages to further develop our approach, toward the design of very high-order schemes, which would represent a very appealing alternative, both in terms of accuracy and efficiency, to now classical FV and ENO/WENO discretizations. These schemes might also be very competitive with respect to very high-order DG schemes. / Doctorat en sciences appliquées / info:eu-repo/semantics/nonPublished
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Analyse de polymères synthétiques par résonance magnétique nucléaire et spectrométrie de masseBarrere, Caroline 26 August 2011 (has links)
Ces travaux de thèse sont consacrés à l’étude, par RMN et spectrométrie de masse, de la caractérisation structurale et la quantification en mélange, de polymères synthétiques à architectures complexes. La caractérisation structurale de copolymères à blocs amphiphiles POE-b-PS a été abordée dans un premier temps par la mise au point d’une nouvelle stratégie, rapide et sans prétraitement, pour la détermination de la masse moyenne en masse par RMN PGSE. La problématique des groupements terminaux fragiles en MALDI-MS, particulièrement cruciale dans le cas de polymères fonctionnalisés par des nitroxydes, a également été traitée. Une approche multidisciplinaire impliquant la RMN, la spectrométrie de masse et la chimie théorique a conduit au développement d’une stratégie de dérivation du groupement terminal labile qui permet la production d’adduits moléculaires intacts MALDI. Par ailleurs, la nécessité de quantifier les impuretés issues de la synthèse de ces macromolécules a conduit au développement d’une stratégie originale, rapide et efficace, basée sur la RMN PGSE. Cette stratégie, qui s’appuie sur la détermination des temps de relaxation magnétique des signaux au cours des expériences, suivie de la renormalisation des intégrales, a notamment soulevé la difficulté de mesurer le temps de relaxation transversale dans le cas de systèmes de spins magnétiquement couplés. Une nouvelle séquence d’impulsions a donc été proposée pour permettre une mesure précise de ce temps de relaxation dans un système de deux spins couplés. / This thesis work deals with two main analytical aspects of PEO-b-PS amphiphilic block copolymers, their structural characterization and their quantitation in mixture, using NMR and mass spectrometry. In a first part, a novel approach was developed for the determination of copolymer weight average molecular weight by PGSE NMR. The issue of MALDI mass analysis of PEO homopolymers functionalized with a labile nitroxide end-group for the purpose of nitroxide mediated polymerization of the PS block was also addressed. A multidisciplinary approach involving NMR, mass spectrometry and theoretical calculation gave rise to an efficient derivatization strategy aimed at allowing intact PEO adducts to be generated by MALDI. In addition, requirement for impurity quantitation in polymer samples led to the development of a rapid and accurate method using PGSE NMR. This approach, based on the measurement of magnetic relaxation times during PGSE experiments to enable signal intensity renormalization, evidenced the issue of transverse relaxation time estimation in the case of coupled spin systems. A novel NMR pulse sequence was hence proposed and successfully applied for accurate measurement of transverse relaxation times in a model case of a two-spin coupled system.
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Accurate wavelength tracking by exciton spin mixingKirch, Anton, Bärschneider, Toni, Achenbach, Tim, Fries, Felix, Gmelch, Max, Werberger, Robert, Guhrenz, Chris, Tomkevičienė, Aušra, Benduhn, Johannes, Eychmüller, Alexander, Leo, Karl, Reineke, Sebastian 06 June 2024 (has links)
Wavelength-discriminating systems typically consist of heavy benchtop-based instruments, comprising diffractive optics, moving parts, and adjacent detectors. For simple wavelength measurements, such as lab-on-chip light source calibration or laser wavelength tracking, which do not require polychromatic analysis and cannot handle bulky spectroscopy instruments, lightweight, easy-to-process, and flexible single-pixel devices are attracting increasing attention. Here, a device is proposed for monotonously transforming wavelength information into the time domain with room-temperature phosphorescence at the heart of its functionality, which demonstrates a resolution down to 1 nm and below. It is solution-processed from a single host–guest system comprising organic room-temperature phosphors and colloidal quantum dots. The share of excited triplet states within the photoluminescent layer is dependent on the excitation wavelength and determines the afterglow intensity of the film, which is tracked by a simple photodetector. Finally, an all-organic thin-film wavelength sensor and two applications are demonstrated where this novel measurement concept successfully replaces a full spectrometer.
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Řízený laboratorní zdroj / Controlled laboratory supplyŠtibraný, Miroslav January 2016 (has links)
Master’s thesis deals with design of laboratory supply with precise voltage and current measuring. At the beginning it presents properties, advantages and disadvantages of linear and switching supplies, based on these facts it chooses a linear type of regulator. The design continues with detailed description of power and control analog and digital circuits. The thesis includes description of taking control over the supply from the front panel or through computer. The last part is devoted to measurement results and to presentation of some static and dynamic parameters of the designed supply.
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Modelování a animace biologických struktur / Modeling and animation of biological structuresMatulík, Martin Unknown Date (has links)
Following work deals with subject matter of digital modelling and animation of biological structures. Software tools for computer generated images (CGI), well proven in common practice, are evaluated, as well as tools for specific activities, available inside chosen software environment. Among vast pool of modelling approaches are discussed tools suitable for creation and representation of selected structures, along with tools essential for their consequent animation. Possible rendering approaches and their parameters in relation to qualities of resulting computer-generated images are discussed as well. Above-mentioned approaches will be consequently utilized for modelling, physical simulation and animation of erythrocyte’s flow throughout blood vessel in following project. Resulting output of that work will be based on series of digital images, suitable for creating video-sequence containing abovementioned animation in end-user digestible form.
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Modelování a animace biologických struktur / Modeling and animation of biological structuresMatulík, Martin January 2018 (has links)
Following work deals with subject matter of digital modelling and animation of biological structures. Software tools for computer generated images (CGI), well proven in common practice, are evaluated, as well as tools for specific activities, available inside chosen software environment. Among vast pool of modelling approaches are discussed tools suitable for creation and representation of selected structures, along with tools essential for their consequent animation. Possible rendering approaches and their parameters in relation to qualities of resulting computer-generated images are discussed as well. Above-mentioned approaches will be consequently utilized for modelling, physical simulation and animation of erythrocyte’s flow throughout blood vessel in following project. Resulting output of that work will be based on series of digital images, suitable for creating video-sequence containing abovementioned animation in end-user digestible form.
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