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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
481

Sobre uma classe de equações elípticas envolvendo crescimento exponencial em ℝ2

Guimarães, Wanderson Rodrigo 16 May 2013 (has links)
Made available in DSpace on 2015-05-15T11:46:22Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 1317724 bytes, checksum: 6a915301a18806d377bf5c949922b304 (MD5) Previous issue date: 2013-05-16 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / In this work, we will study the existence and multiplicity of weak solutions for a class of nonhomogeneous elliptic problems involving exponential growth Trudinger-Moser type in R2. For this, we will use the Ekeland s Variational Principle and the Mountain Pass Theorem without the Palais-Smale condition in combination with a version of the Trudinger-Moser inequality. / Teorema do Passo da Montanha, Principio variacional de Ekeland, equação de Schrodinger, Desigualdade de Trudinger-Moser, Crescimento Exponencial.
482

Decomposição de sinais mioelétricos superficiais: avaliação não-invasiva de desordens neuromusculares / Surface mioeletric signals decomposition: non-invasive evaluation of neuromuscular disorders

Samuel Waldemar Andrade Flôr 18 August 2003 (has links)
Informações sobre as características funcionais e estruturais da unidade motora (UM) são altamente relevantes em investigações fisiológicas e nos estudos clínicos das disfunções neuromusculares. A eletromiografia (EMG) é um método adequado para obtenção dessas informações. Entretanto, devido à dificuldade na separação da atividade individual de uma unidade motora das outras que estão simultaneamente ativas, seu uso em clínica prática se dá comumente através de métodos invasivos, empregando eletrodos de agulha ou fios implantados. Apesar da EMG de superfície ser não-invasiva e, portanto mais apropriada para aplicações clínicas, não é usada em clínica porque não há até o presente um método satisfatório para decomposição do sinal EMG de superfície. Um EMG de superfície é muito mais difícil de decompor devido a significante superposição dos Potenciais de Ação das UMs (MUAPs) e a relação sinal-ruído relativamente baixa, se comparada aos métodos invasivos. Defendemos que a separação da atividade individual das UMs pode ser feita de modo não-invasivo aliando-se técnicas de aquisição altamente especializadas com técnicas usadas em reconhecimento de padrões. Desenvolvemos um método para decomposição de EMGs de superfície, a partir do qual foi possível extrair características relevantes das UMs, que permitem seu uso em avaliação e diagnóstico de desordens neuromusculares. Em nossa abordagem, o sinal EMG é inicialmente captado sob contração isométrica fraca usando eletrodos desuperfície. O sinal EMG bruto passa em seguida por um filtro Diferencial Passa-Baixas Ponderado (DPBP) em série com um detector de picos, que detecta os picos de MUAPs e extrai suas formas de onda. Na sequência, o conjunto de MUAPs extraído é classificado por uma rede neural SOM, e os MUAPs agrupados pela similaridade de suas formas de onda. No próximo passo a informação temporal dos disparos é checada, eliminando possíveis erros de classificação, e finalmente os Trens de MUAPs (MUAPTs) das UMs individuais são reconstituídos do EMG original. As estatísticas de disparos (IPI) bem como as formas de ondas dos MUAPs das respectivas UMs são então extraídas e armazenadas para estudos posteriores. Resultados preliminares obtidos com EMGs normais e patológicos, extraídos de membros superiores sob contração fraca, indicam que, o método mostrou-se apto a decompor EMGs de superfícies, além de potencial para aplicações em estudos clínicos não-invasivos de disfunções neuromusculares.Informações sobre as características funcionais e estruturais da unidade motora (UM) são altamente relevantes em investigações fisiológicas e nos estudos clínicos das disfunções neuromusculares. A eletromiografia (EMG) é um método adequado para obtenção dessas informações. Entretanto, devido à dificuldade na separação da atividade individual de uma unidade motora das outras que estão simultaneamente ativas, seu uso em clínica prática se dá comumente através de métodos invasivos, empregando eletrodos de agulha ou fios implantados. Apesar da EMG de superfície ser não-invasiva e, portanto mais apropriada para aplicações clínicas, não é usada em clínica porque não há até o presente um método satisfatório para decomposição do sinal EMG de superfície. Um EMG de superfície é muito mais difícil de decompor devido a significante superposição dos Potenciais de Ação das UMs (MUAPs) e a relação sinal-ruído relativamente baixa, se comparada aos métodos invasivos. Defendemos que a separação da atividade individual das UMs pode ser feita de modo não-invasivo aliando-se técnicas de aquisição altamente especializadas com técnicas usadas em reconhecimento de padrões. Desenvolvemos um método para decomposição de EMGs de superfície, a partir do qual foi possível extrair características relevantes das UMs, que permitem seu uso em avaliação e diagnóstico de desordens neuromusculares. Em nossa abordagem, o sinal EMG é inicialmente captado sob contração isométrica fraca usando eletrodos desuperfície. O sinal EMG bruto passa em seguida por um filtro Diferencial Passa-Baixas Ponderado (DPBP) em série com um detector de picos, que detecta os picos de MUAPs e extrai suas formas de onda. Na sequência, o conjunto de MUAPs extraído é classificado por uma rede neural SOM, e os MUAPs agrupados pela similaridade de suas formas de onda. No próximo passo a informação temporal dos disparos é checada, eliminando possíveis erros de classificação, e finalmente os Trens de MUAPs (MUAPTs) das UMs individuais são reconstituídos do EMG original. As estatísticas de disparos (IPI) bem como as formas de ondas dos MUAPs das respectivas UMs são então extraídas e armazenadas para estudos posteriores. Resultados preliminares obtidos com EMGs normais e patológicos, extraídos de membros superiores sob contração fraca, indicam que, o método mostrou-se apto a decompor EMGs de superfícies, além de potencial para aplicações em estudos clínicos não-invasivos de disfunções neuromusculares. / Information on the functional and structural characteristics of the motor unit (MU) they are highly important in physiologic investigations and in the clinical studies of the neuromuscular dysfunctions. The electromyography (EMG) it is an appropriate method for obtaining of that information. However, due to the difficulty in the separation of the individual activity of a motor unit of the another that are simultaneously active, your use in practical clinic happen commonly through methods invasive, employing needle electrodes or implanted threads. In spite of surface EMG to be non-invasive and, therefore more appropriate for clinical applications, it is not used at clinic because there is not until the present a satisfactory method for decomposition of the surface EMG sign. A surface EMG is much more difficult of decomposing due to significant overlap of the Motor Unit Action Potentials (MUAPs) and the relationship sign-noise relatively low, if compared to the invasive methods. We defended that the separation of the individual activity of MUs can be made in way non-invasive allying highly specialized acquisition techniques with techniques used in recognition of patterns. We developed a method for decomposition of surface EMGs, starting from which was possible to extract important characteristics of MUs, which allow your use in evaluation and diagnosis of neuromuscular disorders. In our approach, the sign EMG is captured initially under weak isometriccontraction using surface electrodes. The sign EMG raw raisin soon after for a Biased Low-Pass Differential filter (BLPD) in series with a detector of peaks, that detects the peaks of MUAPs and it extracts your wave forms. In the sequence, a SOM neural network classifies the set of extracted MUAPs, and MUAPs are clustered by the similarity in your wave shape. In the next step the temporal information of the discharges is checked, eliminating possible classification mistakes, and finally the MUAPs Trains (MUAPTs) of individual MUs they are reconstituted of original EMG. The statistics of discharges (IPI) as well as the forms of waves of MUAPs of respective MUs are then extracted and stored for subsequent studies. Results preliminaries obtained with normal and pathological EMGs, extracted of superior members under weak contraction, they indicate that, the method was shown capable to decompose surfaces EMGs, besides potential for applications in clinical studies non-invasive of neuromuscular dysfunctions.
483

Pharmacologie de la morphine chez les sujets obèses avant et après chirurgie de l'obésité / Pharmacology of morphine in obese subjects before and after obesity surgery

Lloret Linares, Célia 19 April 2013 (has links)
Au cours de cette thèse, nous montrons que l’obésité est un facteur de variabilité pharmacodynamique et pharmacocinétique de la morphine. En particulier, l’absorption et l’exposition à la morphine orale augmentent de façon significative après chirurgie de type bypass gastrique. Nous démontrons le rôle du contenu entérocytaire en transporteur d’efflux P-gp, dans la détermination de l’absorption et de l’exposition à la morphine. / In this thesis, we show that obesity is a factor of pharmacodynamic and pharmacokinetic morphine variability. In particular, absorption and exposure to oral morphine increases significantly after gastric bypass surgery . We demonstrate the role of enterocyte content of efflux transporter P-gp in determining the absorption and exposure to morphine.
484

Monetary policy in the context of Vietnamese economy / Politique monétaire dans le contexte de l'économie vietnamienne

Le Huy, Chinh 04 December 2015 (has links)
Cette thèse propose quatre contributions à l'étude de la politique monétaire dans le contexte de l'économie vietnamienne, depuis 1995-1996 jusqu’à maintenant.Le premier chapitre donne aperçu de l'économie vietnamienne et sa politique monétaire. Il s’agit d’un chapitre qui problématise les questions traitées économétriquement dans le reste de la thèse.Chapitre 2 montrent qu'il y a une relation à long terme entre le taux de change du marché noir et ses variables monétaires. Le taux de change officiel, l’écart de la masse monétaire et de taux d'intérêt intérieur ont des effets positifs significatifs sur le taux de change du marché noir tandis que la production intérieure réelle et le taux d'intérêt à l'étranger ont un impact négatif significatif sur cet indice. Chapitre 3 fournissent de fortes preuves relatives à la relation à long terme entre taux de change et ses fondamentaux monétaires relatifs. Bien que les signes des taux d'intérêt estimés soient ambigu, les coefficients estimés de la monnaie et du rendement sont compatibles avec toutes les variantes traditionnelles du modèle monétaire de la détermination du taux de change. Finalement, nous constatons que le pass-through du taux de change sur l'inflation est fort et rapide, et que le taux de change a un effet positif significatif sur l'inflation. La masse monétaire joue un rôle important dans la détermination de l'inflation alors que le taux d'intérêt ne semble pas avoir un impact significatif sur l'inflation. En outre, le prix du pétrole l’influence considérablement. Un choc de taux d’intérêts des États-Unis joue un rôle insignifiant dans l’explication de la variabilité des variables macroéconomiques domestiques. / This dissertation proposes four contributions to the study of monetary policy in the context of Vietnamese economy from 1995-96 onwards. The first chapter provides an overview of Vietnamese economy and its monetary policy. It provides some issues that are resolved econometrically in the rest of the thesis.The second chapter investigates the black market exchange rate determination. We find that there is a long-run relationship between black market exchange rate and its relative monetary variables. Official exchange rate, money supply differential and domestic interest rate have significant positive effects on black market exchange rate while domestic real output and foreign interest rate have meaningful negative impact on black market exchange rate.The third chapter examines how well versions of monetary models explain the VND/U.S dollar exchange rate. Estimates provide strong evidences of long-run relationship between exchange rate and its relative monetary fundamentals. Although the signs of estimated interest rates are mixed, estimated coefficients of money and output are consistent with any traditional variant of monetary model of exchange rate determination. Eventually, we find that the exchange rate pass-through to inflation is high and rapid, and exchange rate has a significant positive effect of exchange rate on inflation. Estimates also reveal that money supply plays a significant role in shaping inflation while interest rate does not seem to have a meaningful impact on inflation. In addition, oil price also has significant impact on inflation. U.S interest rate shock plays an insignificant role in explaining the variability of domestic macro variables.
485

The impact of the real effective exchange rate on South Africa's trade balance

Matlasedi, Nchokoe Tony January 2016 (has links)
Thesis (M. Commerce (Economics)) -- University of Limpopo, 2016 / The purpose of this paper is to ascertain the impact of the real effective exchange rate on South Africa‟s trade balance and whether the J-curve phenomenon and the Marshal-Lerner condition are satisfied in the economy. Using data spanning the period 1980Q1 – 2014Q4, the Autoregressive Distributed Lag (ARDL) bounds test as well as the Johansen cointegration test were employed to test for the long run cointegrating relationship between the variables. The ARDL approach was employed to estimate both the long run and short run models as well as to ascertain whether the Marshal – Learner condition as well as the J-curve phenomenon are satisfied in the RSA economy. The results from the cointegration tests show that there is a stable long run equilibrium relationship between the trade balance, real effective exchange rate, domestic GDP, money supply, terms of trade and foreign reserves. The results from the Autoregressive Distributed Lag long run model show that a depreciation of the ZAR improves the trade balance, thus confirming the MarshalLerner condition. The results further reveal that domestic GDP and money supply both have a significant negative impact on the trade balance in the long run with the terms of trade reported positive as well. Foreign reserves were not found to significantly affect the trade balance in the long run. In the short run, the ARDL error correction model shows that a ZAR depreciation leads to a deterioration of the trade balance, thus confirming the J-curve effect for the RSA economy. The terms of trade effect was reported positive in the short run, thus confirming the Harberger-LaursenMetzler effect (HLME) in the process. Money supply, domestic GDP and foreign reserves are also found to have a significant negative impact on the trade balance in the short run. Finally, the error correction model reveals that about 26% of the disequilibrium in the trade balance model is corrected in each quarter.
486

Vliv polohy reproduktorů na charakteristiky reproduktorové soustavy / Influence of drivers position on the characteristics of the loudspeaker system

Bičan, Jan January 2021 (has links)
This thesis deals with the measurement and description of properties of the two-way variable modular loudspeaker system marked as OM-3, especially the influence of the mutual position of drivers on its characteristics. The thesis examines individual factors taking their contribution on characteristics of the loudspeaker system in total. Further it measures and evaluates options of compensations of mutual position changes of drivers using an all-pass filter. Within this thesis is also included laboratory task preparation which is focused on this problematics.
487

Nízkošumový zesilovač pro pásmo S / Low Noise Amplifier for the S Band

Benites Ayala, Ivan Alejandro January 2019 (has links)
This master's thesis presents the design and the realization of a low noise amplifier (LNA) for the S band of radio frequency spectrum from 2.3 GHz to 2.4 GHz. This thesis is mainly focused on stability and impedance matching networks study. Ansoft Designer and ANSYS HFSS programs are used for this design to simulate the LNA. Different low noise devices are simulated in order to find the best results for the final design. Moreover, a coaxial cavity resonator is designed in the input of the LNA and works as a band pass filter. Finally, the LNA is fabricated and its properties compared with the simulation results.
488

Fázovací obvody s moderními funkčními bloky / All-pass filters based on modern functional blocks

Horák, Ondřej January 2009 (has links)
The present thesis is focused on all pass filters. The principle of all pass filters, their properties, the design of nth degree of these circuits will be analysed in succession and then some of functional blocks, by which these structures can be made, will be described. After that, the allpass filters will be designed and simulated in program OrCAD PSpice. First of all, the analysis will be performed with ideal components, then with real components. After that, the sensitivity and tolerance analysis will be made and the influence of parasite effects on circuit parameters will be examined. Once the experiments are finished, the design of Printed Circuit Board's (PCB) will be realized. Circuit showing the best parameters will be chosen for the design.
489

Ultrazvukový měřič rychlosti toku krve / Ultrasonic blood flow meter

Pavlík, Dušan January 2011 (has links)
This thesis deals with ultrasound blood flow meter design with emphasis on practical implementation of such device. This medical device is used in ultrasound diagnostic, especially for measuring direction and velocity of blood flow in superficial vessels. This thesis contains consecutive design including description of individual function blocks. Documents for making double-sided printed circuit are included as well.
490

Výpočet ustáleného chodu sítě 22 kV v zadané oblasti / Steady state calculation of 22kV network

Kaplanová, Klára January 2012 (has links)
Master's thesis proposes a new operation state of distribution network 22kV in Prostějov district after connection of the new Prostějov – Západ substation. The PASS DAISY OFF-LINE Bizon program is used to calculate power losses, optimal network possibilities, as well as to create a new model of Prostějov district's distribution network and to design a modification of a current state of given location. A description of this calculating and simulation program is also included in this paper. The theoretical part describes calculating methods of distribution network’s condition, with emphasis on mathematical method used by PASS DAISY OFF-LINE Bizon program, the modified Newton-Raphson method. The aim of this paper is to prepare technical documentation for E.ON company, with respect to new operation disconnection, planned overhead and cable lines of corresponding parameters. These changes in network's configuration will cause a new distribution of feeding areas. As a result, related changes of provided power from individual feeding points and changes of power currents in electric lines will occur. Due to new operation connection, a reduction of losses and, simultaneously, an improvement of voltage ratios are expected. One of the aims of this paper is to update network's model in PASS DAISY OFF-LINE Bizon program to match the current network’s state of a given area. The outcome of this work is a comparison between the current condition and the new operation condition, with new Prostějov – Západ substation connected, from perspective of distribution network's operator.

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