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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.
51

Applying "Real Time Grouting Control Method" in sedimentary rock with gotvand dam data

Yaghoobi Rafi, Jalaleddin January 2010 (has links)
“Real Time Grouting Control Method” is a pioneer idea informulating grouting works which provides possibility for monitoring groutingprocess in real time to optimize it to performance and cost. Currently this theoryhas been tested with data from tunnels in Stockholm. In this report the effort istesting the validity of this method in a kind of geology which is situated insouthwest of Iran. Data are taken from the Gotvand dam project which is underconstruction on Karoon River. To achieve this goal, Tests are performed inStockholm by using the cement collected from the dam site to obtain rheologicaland penetrability properties of the grout mix which is in use in Gotvand project.Pressure and flow values are recorded in during grouting and have beenemployed as input data in this report. By developing a proper application, resultshave been analysed and discussed in detail. It has been shown that in studiedcases the theory can provide promising results and this method is applicable inthis project although there is a need for site investigation and testing different kindof grout mixes to precise results and be able to drive a general conclusion. / QC 20101009
52

Consent to organ donation and family authorization : A causal inference study of the French amendment of article L1232-1 in Code de la santé publique and organ donations

Lundberg, Moa January 2022 (has links)
The world is experiencing a lasting shortage of organ donations – a problem more severe in some countries than others. Literature on the matter argues that an explanation for this is the various legal default consent systems, and the importance put on the opinions of the family members regarding the donation question in case of sudden death. This paper establishes the causal inference between cadaveric organ donation rates and the French amendment of the public health code, of 2017, which limited the authorization given to the family members - aiming to decrease family refusal rates and consequently increase cadaveric organ donation rates. By applying the synthetic control method, a synthetic counterfactual to France is constructed from a donor group, including comparable European countries. The counterfactual, Synthetic France, resembles what would have happened in France in the absence of the amendment. The results show that the legal amendment of article L1232-1 in the public health code (code de la santé publique) was likely the driving force behind the increased donation rate in the subsequent years. The main finding of this study is robust and statistically significant, providing confidence to the claim of causal inference.
53

Srovnání vybraných středoškolských českých a německých učebnic dějepisu / Comparison of selected Czech and German High school textbooks

Žabová, Martina January 2013 (has links)
The topic of the presented thesis is a comparison of selected contemporary Czech and German history textbooks, designed for high schools. It analyzes the Czech and the German high school system, with a focus on the teaching history. It compares the structure of the textbooks, verbal and visual content, control methods and the adoption process of the subject matter.
54

Efetividade da tripsina sobre embriões murinos infectados experimentalmente com BoHV-1. / Effectiveness of trypsin on murine embryos experimentally infected with BoHV-1.

Palazzi, Eduardo Gimenes 12 November 2010 (has links)
O presente trabalho avaliou a efetividade do tratamento com tripsina (TT) na eliminação do BoHV-1 Colorado, causador da Rinotraqueíte Infecciosa Bovina (IBR). Camundongos fêmeas Swiss, com idade entre 6 e 8 semanas, foram superovuladas com 0,2mL a 5UI de hormônio eCG e, após 48h com hCG e acasaladas com machos inteiros da mesma linhagem e idade. Após 18 horas, as fêmeas foram eutanasiadas e, através de abertura no peritônio, os zigotos foram coletados. Foram separados zigotos para cinco ensaios que forneceram os seguintes dados: o BoHV-1 Colorado altera a taxa de clivagem e a morfologia do embrião; a tripsina, seguindo recomendações da IETS, não danifica o embrião; os embriões expostos aos vírus e submetidos ao TT não alteram sua morfologia e taxa de clivagem; foram detectados (nested-PCR+) vírus viáveis (MDBK+) após o TT. Estes resultados demonstram que o TT não foi efetivo para eliminar o BoHV-1 Colorado, porém em alguns ensaios o TT demonstrou eficiência na inativação do vírus o que torna-o um importante método de controle in vitro. / This study evaluated the effectiveness of treatment with trypsin (TT) in the elimination of BoHV-1 Colorado, which causes infectious bovine rhinotracheitis (IBR) Swiss female mice, aged 6 and 8 weeks, were superovulated with 0.2 mL 5UI hormone eCG and 48h after hCG and mated with males of the same lineage and age. After 18 hours, females were euthanized, and through na opening in the peritoneum, the zygotes were collected. Zygotes were separated for five trials that provided the following data: the Colorado BoHV-1 alters the cleavage rate and embryo morphology; trypsin, following recommendations of the IETS, does not damage the embryo; the embryos exposed to the virus and subjected to TT does not change their morphology and cleavage rate; were detected (nested-PCR +) viable virus (MDBK +) after the TT. These results demonstrate that TT was not effective to eliminate the BoHV-1 Colorado, but in some tests showed the TT efficiency in inactivating the virus makes it na important method of control in vitro.
55

Tiesiaeigės dažninės pavaros tyrimas / Research of linear variable frequency drive

Jenkinas, Piotras 08 June 2004 (has links)
The properties of linear induction motor and areas of its application are analyzed; frequency converters and their control methods are discussed in this final work. Methods to realize a pulse width modulation are analyzed, scalar and vector control principles as well as perspectives of perfection of semiconductor commutating elements and control systems are discussed. The principle of operation of control systems applied in frequency converters is analyzed On the base of analysis mathematical and Simulink model of linear induction motor in α-β reference frame is developed, mathematical and Simulink models of frequency controlled linear induction drives are carried out. Two models of linear frequency controlled induction drive: scalar and vector control are investigated, transient characteristics of inverter output voltage, currents of linear motor, developed force and linear speed are analyzed and results of different control principles are compared.
56

Efetividade da tripsina sobre embriões murinos infectados experimentalmente com BoHV-1. / Effectiveness of trypsin on murine embryos experimentally infected with BoHV-1.

Eduardo Gimenes Palazzi 12 November 2010 (has links)
O presente trabalho avaliou a efetividade do tratamento com tripsina (TT) na eliminação do BoHV-1 Colorado, causador da Rinotraqueíte Infecciosa Bovina (IBR). Camundongos fêmeas Swiss, com idade entre 6 e 8 semanas, foram superovuladas com 0,2mL a 5UI de hormônio eCG e, após 48h com hCG e acasaladas com machos inteiros da mesma linhagem e idade. Após 18 horas, as fêmeas foram eutanasiadas e, através de abertura no peritônio, os zigotos foram coletados. Foram separados zigotos para cinco ensaios que forneceram os seguintes dados: o BoHV-1 Colorado altera a taxa de clivagem e a morfologia do embrião; a tripsina, seguindo recomendações da IETS, não danifica o embrião; os embriões expostos aos vírus e submetidos ao TT não alteram sua morfologia e taxa de clivagem; foram detectados (nested-PCR+) vírus viáveis (MDBK+) após o TT. Estes resultados demonstram que o TT não foi efetivo para eliminar o BoHV-1 Colorado, porém em alguns ensaios o TT demonstrou eficiência na inativação do vírus o que torna-o um importante método de controle in vitro. / This study evaluated the effectiveness of treatment with trypsin (TT) in the elimination of BoHV-1 Colorado, which causes infectious bovine rhinotracheitis (IBR) Swiss female mice, aged 6 and 8 weeks, were superovulated with 0.2 mL 5UI hormone eCG and 48h after hCG and mated with males of the same lineage and age. After 18 hours, females were euthanized, and through na opening in the peritoneum, the zygotes were collected. Zygotes were separated for five trials that provided the following data: the Colorado BoHV-1 alters the cleavage rate and embryo morphology; trypsin, following recommendations of the IETS, does not damage the embryo; the embryos exposed to the virus and subjected to TT does not change their morphology and cleavage rate; were detected (nested-PCR +) viable virus (MDBK +) after the TT. These results demonstrate that TT was not effective to eliminate the BoHV-1 Colorado, but in some tests showed the TT efficiency in inactivating the virus makes it na important method of control in vitro.
57

[pt] IDENTIFICAÇÃO NÃO LINEAR CAIXA-PRETA DE SISTEMAS PIEZOELÉTRICOS / [en] NONLINEAR BLACK-BOX IDENTIFICATION OF PIEZOELECTRIC SYSTEMS

MATHEUS PATRICK SOARES BARBOSA 10 September 2021 (has links)
[pt] Atuadores baseados em materiais piezelétricos apresentam características ideais para aplicações como transmissão acústica e micromanipulação. No entanto, não-linearidades inerentes a estes atuadores, como histerese e fluência, aumentam o desafio de controla-los. Além disso, a crescente necessidade de atuadores mais precisos e rápidos aliada a frequentes mudanças nas condições ambientais e operacionais agravam ainda mais o problema. Modelagens analíticas são específicas ao sistema ao qual foram feitas, o que significa que elas não são facilmente escalonáveis e eficientes para todos os tipos de sistemas. Adicionalmente, com o aumento da complexidade, os fenômenos que regem a física do sistema não são totalmente conhecidos, tornando difícil o desenvolvimento destes modelos. Este trabalho investiga esses desafios do ponto de vista da metodologia de identificação de sistemas e modelos baseados em dados para atuadores piezelétricos. A abordagem de modelagem caixa preta foi testada com dados experimentais adquiridos em um ambiente de laboratório para os estudos de caso de micromanipulação e transmissão acústica. Sinais de uso geral foram empregados como entrada de excitação do sistema de modo a acelerar a aquisição e estimação dos parâmetros. Parte dos modelos desenvolvidos foram validados com um conjunto de dados separado. Em ambos os casos foi necessário pré-processamento para otimização da quantidade de dados. Os modelos testados incluem a Média Móvel AutoRegressiva com entradas eXógenas (ARMAX), AutoRegressiva Não Linear com entradas eXógenas (NARX) com uma estrutura de rede neural artificial e Média Móvel AutoRegressiva Não Linear com entradas eXógenas (NARMAX). Os resultados mostram uma boa capacidade de prever as não-linearidades do micro manipulador e, portanto, a histerese em diferentes frequências de entrada. O sistema de transmissão acústica foi modelado com sucesso. Embora os resultados mostrem que ainda há espaço para melhorias, eles fornecem informações importantes sobre possíveis otimizações para o sistema uma vez que os modelos apresentados são uteis para janelas de predição curtas. / [en] Actuators based on piezoelectric materials have ideal characteristics for applications such as acoustic transmission and micromanipulation. However, the inherent nonlinearities of those actuators, such as hysteresis and creep, greatly increase the challenge to control such devices. Furthermore, the increasing need for more precise and faster actuators, allied with frequent changes in the environmental and operational conditions, further worsens the problem. Analytical models are application-specific, meaning that they are not easily and efficiently scalable to all systems. Also, with increased complexity, the understating of underlying phenomena is not fully documented, making it difficult to develop such models. This work investigates those challenges from the perspective of the system identification methodology and data-driven models for piezoelectric actuators. The black-box approach is tested with experimental data acquired in a laboratory setting for micromanipulator and acoustic transmission case studies. In some datasets, general-purpose signals were employed as the excitation input of the system to accelerate the data acquisition of the whole system dynamic and estimation process. Additionally, some models were validated on a separate dataset. In both cases, preprocessing was employed to optimize the amount of data. The tested models include the AutoRegressive Moving Average with eXogenous inputs (ARMAX), Nonlinear AutoRegressive with eXogenous inputs (NARX) with an artificial neural network structure, and Nonlinear AutoRegressive Moving Average with eXogenous inputs (NARMAX). The results show a good ability to predict the nonlinearities of the micromanipulator and, therefore, the hysteresis at different input frequencies. The acoustic transmission system was successfully modeled. Although the results show that there is still room for improvements, it provides insights into possible optimizations for the setup as the models here devised are useful for short prediction windows.
58

Robust Adaptive Control of a Laser Beam System for Static and Moving Targets

Samantaray, Swastik January 2016 (has links) (PDF)
The motivation of this thesis is to propose a robust control technique for a laser beam system with target estimation. The laser beam is meant to track and fall on a particular portion of the target until the operation is accomplished. There are many applications of such a system. For example, laser range finder uses laser beam to determine the distance of the target from the source. Recently, unmanned aerial drones have been developed that run on laser power. Drone batteries can be recharged with power sup-ply from laser source on the ground. Laser is also used in high energy laser weapon for defence applications. However, laser beams travelling long distances deviate from the desired location on the target due to continually changing atmospheric parameters (jitter effect) such as pressure, temperature, humidity and wind speed. This deviation error is controlled precisely using a lightweight fast steering mirror (FSM) for fine correction. Furthermore, for a moving target, minimizing the deviation of the beam is not sufficient. Hence, in coarse correction, the target has to be tracked by determining its position and assigning the corresponding azimuth and elevation angles to the laser sources. Once these firing angles are settled within an accuracy of +3 mrad, the effort for minimizing the beam deviation (fine correction) takes place to improve the accu-racy to +10 rad. The beam deviation due to jitter effect is measured by a narrow field of view (NFOV) camera at a high frame rate (1000 frames per second), which takes one frame to com-pute this error information. As a result, controller receives error information witha delay from NFOV. This data cannot be modelled for prediction and hence, a few promising data driven techniques have been implemented for one step ahead prediction of the beam deviation. The predictions are performed over a set of sliding window data online after rejecting the outliers through least square approximated straight line. In time domain, methods like auto-regressive least square, polynomial extrapolation (zeroth, first and second order), Chebyshev polynomial extrapolation, spline curve extrapolation are implemented. Further, a convex combination of zeroth order hold and spline extrapolation is implemented. In frequency domain, Fourier series-Fourier transform and L-point Discrete Fourier Transform stretching are implemented where the frequency component of the signal are analysed properly and propagated for one step ahead prediction. After one step ahead prediction, three nominal controllers (PID, DI and DLQR) are designed such that the output of FSM tracks the predicted beam deviation and the performances of these controllers are compared. Since the FSM is excited by high frequency signals, its performance degrades, which leads to parameter degradation in the mathematical model. Hence, three adaptive controllers have been implemented, namely, model reference adaptive control (MRAC), model reference adaptive sliding mode control (MRASMC) and model following neuro-adaptive control (MFNAC). The parameters of the FSM model are degraded up to 20% and the model is augmented with cross coupling terms because the same mirror is used for horizontal and vertical beam deviation. With this condition, the tracking performance and control rate energy consumption of the implemented adaptive controllers are analysed to choose the best among them. For a moving target, in coarse correction, two tracking radars are placed to measure the position of the target. However, this information is assumed to be noisy, for which an extended Kalman filter is implemented. Once the position of the target is known, the desired firing angles of the laser sources are determined. Given the laser source steering mathematical model, a controller is designed such that it tracks the desired firing angle. Once the residual error of the coarse correction settles inside 3 mrad, fine correction takes part to reduce the residual error to 10 rad. The residual error magnitude of the proposed mechanization was analysed for a moving target by perturbing the FSM model by 20% and zeroth order hold predictor with different combinations of angle tolerance and frame tolerance.
59

Assessing public sector performance in developing countries : four essays on public financial management and public service delivery / L'évaluation des performances du secteur public dans les pays en développement : Quatre essais sur la gestion des finances publiques et la prestation de service public

Sarr, Babacar 19 January 2015 (has links)
Le secteur public joue un rôle important dans la société. Dans la plupart des pays en développement, les dépenses publiques constituent une partie importante du PIB et les entités du secteur public sont les principaux pourvoyeurs d’emploi et les principaux acteurs du marché des capitaux. Le secteur public détermine, généralement par le biais d'un processus politique, ses objectifs économiques et sociaux ainsi que les différents types d'intervention à mettre en place pour les atteindre. Comment le secteur public atteint ses objectifs constitue une question cruciale étant donné que sa taille et son importance économique en font un moteur principal de la croissance et du bien-être social. Ses performances sont jugées à travers la qualité et la nature de sa gestion des finances publiques, les infrastructures qu'il finance ainsi que la qualité de sa régulation des activités économiques. La manière dont les activités du secteur public délivrent les résultats attendus est ainsi une variable clé du développement; pourtant les études empiriques pour comprendre ce qui fonctionne dans le secteur public et pourquoi restent remarquablement limitées. Deux principales raisons expliquent cette situation: les performances dans ce secteur sont difficiles à analyser car les outputs des divers services qu’il fournit sont difficiles à mesurer et même à définir, et le manque de données quantitatives et qualitatives rend difficile une analyse économétrique rigoureuse.Dès lors, l’objectif de cette thèse est de documenter cette littérature et de proposer différentes méthodes empiriques pour évaluer les performances du secteur public dans les pays en développement. Notre analyse est organisée comme suit: la Première Partie - Chapitres 1 et 2 - présente deux essais sur l’évaluation des performances du secteur public “en amont” tandis que la Seconde Partie - Chapitres 3 et 4 - présente deux essais sur l’évaluation des performances du secteur public “en aval” Le Chapitre 1 fait usage de la technique de Blinder-Oaxaca pour examiner comment la qualité des institutions budgétaires affecte les performances budgétaires – déficit budgétaire et dette publique - en Afrique sub-Saharienne. Dans le Chapitre 2, nous utilisons une approche par le Synthetic Control pour étudier l'impact des Offices de Recettes sur la mobilisation des ressources publiques dans une vingtaine de pays en développement. Le Chapitre 3 présente un Benchmarking systématique des performances infrastructurelles de l'Afrique dans les secteurs de l'électricité, de l'eau et de l’assainissement, des technologies de l'information et de la communication, et des transports. Enfin nous évaluons, dans le Chapitre 4, les effets de la mise en place d'une Autorité Indépendante de Régulation sur les performances du secteur de l'électricité dans les pays en développement. / The public sector plays a major role in society. In most developing countries, public expenditure represents a significant part of gross domestic product (GDP) and public sector entities are substantial employers and major capital market participants. The public sector determines, usually through a political process, the outcomes it wants to achieve and the different types of intervention. How the public sector achieves results matters as its size and economic significance make it a major contributor to growth and social welfare. Its achievements emerge in the quality and nature of its financial management, the infrastructure it finances and the quality of its social and economic regulation. How well those public sector activities deliver their expected outcomes is a key development variable; yet explicit evidence base for understanding what works and why in the public sector remains strikingly limited compared with other policy areas. There are two main reasons for this situation: the performance in these areas is difficult to analyze because the outputs of many such services are hard to measure or even to define, and the lack of quantitative and qualitative longitudinal data precludes rigorous econometric analysis.Therefore the objective of this thesis is to document this literature and to propose different ways of measuring public sector performance in developing countries. The dissertation is divided into two Parts: the first Part – Chapters 1 and 2 – presents two essays on “upstream” public sector performance while the second Part – Chapters 3 and 4 – presents two essays on “downstream” public sector performance. The Chapter 1 makes use of the Blinder-Oaxaca Decomposition to examine how the quality of budget institutions affects fiscal performance – Primary Balance and Public Debt – in sub-Saharan Africa. In Chapter 2 we use a Synthetic Control Approach to investigate the impact of Semi-Autonomous Revenue Authorities (SARAs) on revenue mobilization in twenty developing countries. The chapter 3 provides a first systematic Benchmarking of Africa’s infrastructure performance on four major sectors: electricity, water and sanitation, information and communication technologies, and transportation. Finally we evaluate the effects of the establishment of an Independent Regulatory Authority (IRA) on electricity sector performance in developing countries in Chapter 4.
60

Vliv Tomáše a Jana Antonína Bati na rozvoj města Otrokovice / Influence of Thomas and Jan Atonín Bata on the town Otrokovice development

Malotová, Hana January 2013 (has links)
Theme that I dealt in my dissertation with, concerns of my hometown Otrokovice and also to the region in which the city is located. Describes the development and building of this place,and especially of city districtsBaťov,which took place here in the 20th and 30 the last century. Under the leadership of brothers Tomas and Jan Antonín Bata here arose ideal industrial town, the only of its kind in the country. This is not qustion just about new town plan, but also a new type of labor and social relations. In my work I deal with not only the sociological impact of this process on indigenous peoples but also a new way of educating young people, the concept of discipline and the phenomenon of collective consciousness. I also asked myself about the sustainable development of Down Otrokovice to the environmental and economic, and their possible future. There is also a comparison with the nearby Zlin, where Bata began the process of transforming. Mentioned town is still the center of the region and tradition bearers of this system.

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