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Making their mark, Canadian snipers and the Great War, 1914-1918Mepham, Leslie P. January 1997 (has links) (PDF)
No description available.
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As taxas de retorno dos projetos de concessão e PPP do setor de rodoviasIto, Minoru 26 February 2015 (has links)
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Previous issue date: 2015-02-26 / As concessões e as Parcerias Público-Privadas (PPP) são mecanismos cada vez mais utilizados pelo setor público para alavancar os investimentos em infraestrutura no país. Para que haja viabilidade econômica das mesmas, as suas taxas internas de retorno (TIR) apresentam-se como variáveis que precisam refletir os riscos e a realidade do negócio. O presente estudo busca analisar as taxas de retorno utilizadas para a modelagem das tarifas-teto do setor de rodovias federais frente às especificidades do seu mercado. Para tal, são seguidas três frentes: a primeira é analisar a metodologia da taxa de retorno utilizada para a modelagem das concessões mais recentes de rodovias; a segunda é estimar uma taxa de retorno a partir de pesquisa bibliográfica; e a terceira é, por meio de dados de rentabilidade de balanços de concessionárias do setor, observar se as taxas de retorno das primeiras concessões foram devidamente calculadas na época. Na dissertação, concluímos que a atual metodologia da taxa de retorno do Tesouro Nacional pode ser aprimorada, principalmente em relação aos parâmetros de grau de alavancagem e capital de terceiros, e observamos que a taxa de retorno tem se aproximado do custo de oportunidade do setor ao longo das últimas etapas de concessão. O estudo visa contribuir para o debate sobre a rentabilidade dos projetos de infraestrutura rodoviária, em meio a um período de intensos investimentos no setor. / Concessions and Public-Private Partnerships (PPP) are mechanisms increasingly used by the public sector to enhance the investments in infrastructure in Brazil. To achieve economic viability in these projects, their internal rates of return (IRR) are variables which must reflect the risks and reality of the business. The present study seeks to analyse the IRRs used for modeling the price-caps of the federal highways’ sector, under the specificities of such market. For this purpose, three approaches are pursued: the first one analyses the methodology of IRR calculation applied for modelling the most recent highway concessions; the second estimates an IRR based on bibliographic research; and the third makes use of data acquired from the balance sheets from the sector`s concessionaries, to observe if the IRR for the f irst concessions of federal highways were properly calculated at the time. In this dissertation, we concluded that the current National T reasury´s methodology of the rate of return can be improved, especially in relation to parameters like leverage and debt, and we observed that the rate of return has come closer to the opportunity cost for the sector throughout the last concession rounds. This study aims to contribute to the debate on the profitability of road infrastructure projects, a midst a period of intense investments in the sector.
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Contrôle optimal géométrique et numérique appliqué au problème de transfert Terre-Lune / Numerical and geometric control methods and applications to the Earth - Moon transfert problemPicot, Gautier 29 November 2010 (has links)
L'objet de cette thèse est de proposer une étude numérique, fondée sur l'application de résultats de la théorie du contrôle optimal géométrique, des trajectoires spatiales du système Terre-Lune dans un contexte de poussée faible. Le mouvement du satellite est décrit par les équations du problème restreint des trois corps controlé. Nous nous concentrons sur la minimisation de la consommation énergétique et du temps de transfert. Les trajectoires optimales sont recherchées parmi les projections des courbes extrémales solutions du principe du maximum de Pontryagin et peuvent être calculées grâce à une méthode de tir. Ce procédé fait intervenir l'algorithme de Newton dont la convergence nécessite une initialisation précise. Nous surmontons cette difficulté au moyen de techniques homotopiques ou d'études géométriques du système de contrôle linéarisé. L'optimalité locale des trajectoires extrémales est ensuite vérifée en utilisant les conditions du second ordre liées au concept de point conjugué. Dans le cas du problème de minimisation de l'énergie, une technique de "recollement" de trajectoires optimales kepleriennes autour de la Terre et La Lune et d'une solution optimale de l'équation du mouvement linéarisée au voisinage du point d'équilibre L1 est également proposée pour approximer les transferts Terre-Lune à énergie minimale. / This PhD thesis provides a numerical study of space trajectories in the Earth-Moon system when low-thrust is applied. Our computations are based on fundamental results from geometric control theory. The spacecraft's motion is modelled by the equations of the controlled restricted three-body problem. We focus on minimizing energy cost and transfer time. Optimal trajectories are found among a set of extremal curves, solutions of the Pontryagin's maximum principle, which can be computed solving a shooting equation thanks to a Newton algorithm. In this framework, initial conditions are found using homotopic methods or studying the linearized control system. We check local optimality of the trajectories using the second order optimality conditions related to the concept of conjugate points. In the case of the energy minimization problem, we also describe the principle of approximating Earth-Moon optimal transfers by concatening optimal keplerian trajectories around The Earth and the Moon and an energy-minimal solution of the linearized system in the neighbourhood of the equilibrium point L1.
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Svítidla a aplikace s Power LED zdroji / Luminaires and Applications with Power LEDsVaňko, Adam January 2011 (has links)
Progress in development of modern LEDs, their long lifetime and high luminous efficacy predetermine them for usage in lighting systems. This master's thesis examines possibilities of application of LEDs in luminaires, parameters of diodes and problems, which can appear in construction of luminaire with LED lighting source. In the practical part of this thesis a luminaire is designed, capable of illuminating traffic signs, vertical surfaces, billboards and fasades. By standards required parameters of a lighting system and adaptability of application must be considered in complex predesign. Simulations of lighting scene, created in special computer software, measurements of optical point’s parameters and construction of real luminaire model using high quality CREE LEDs, are included in analysis of the problem. Parameters of the luminaire were proved by measurements of product’s attributes at light laboratory. There are also some suggestions for improvement and further development of the product.
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Procesado, modelización y caracterización de mezclas industriales de SEBS con materiales con cambio de fase (PCM) para la mejora del confort térmico en aplicaciones de ortopedia y puericulturaJuárez Varón, David 19 September 2011 (has links)
El sector de puericultura y ortopédico son sectores de gran relevancia, donde aspectos como el confort, adaptabilidad, calidez, etc. adquieren sentido. Los cauchos basados en silicona líquida (LSR) son clave en estos sectores, ofreciendo interesantes propiedades tanto a nivel técnico como de percepción positiva por parte del usuario. No obstante, la transformación de estos materiales es algo más compleja que el conjunto de plásticos de uso común y además, debido a su naturaleza reticular, resulta un material difícil de reciclar.
El proceso de inyección es un proceso de conformado de los materiales poliméricos termoplásticos que representa una notable importancia económica y tecnológica.
Bajo estas premisas, el objetivo principal de este trabajo de investigación es el desarrollo de materiales para el sector ortopédico - puericultura a partir del empleo de materiales de naturaleza reticular reversible (elastómeros termoplásticos) que puedan procesarse mediante técnicas de inyección convencionales y que sean capaces de aportar una buena inercia térmica para confort, mediante el empleo de materiales microencapsulados con cambio de fase (PCMs).
Para ello, se plantea un conjunto de mezclas de un sistema basado en dos grados comerciales de elastómero termoplástico de SEBS (copolímero en bloque de estireno-etileno/butileno-estireno) con durezas extremas. Ello conlleva el planteamiento de objetivos parciales como la caracterización reológica del sistema (desarrollando un modelo de predicción de comportamiento mediante software de simulación), la modelización del comportamiento mecánico de las mezclas, la optimización del procesado de las mezclas aditivadas con PCMs (analizando la respuesta mecánica y térmica) y el estudio de la inercia térmica de las mismas para la mejora del confort de estos materiales y su potencial empleo en los sectores industriales mencionados, como sustitutos en las aplicaciones de la silicona líquida inyectada. / Juárez Varón, D. (2011). Procesado, modelización y caracterización de mezclas industriales de SEBS con materiales con cambio de fase (PCM) para la mejora del confort térmico en aplicaciones de ortopedia y puericultura [Tesis doctoral]. Editorial Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/11551 / Palancia
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Uso de Aisladores Sísmicos Para Edificios Multifamiliares. Caso De Estudio: Edificio Multifamiliar Residencial HungríaFernández Loayza, Jannet, Quispe Vilca, Albert Dante, Vargas Salazar, Raúl Daniel, Lucero Rojas, Katherine Reyna, Alva Jiménez, Alfonso Renato 26 October 2020 (has links)
Nuestro proyecto busca demostrar que se puede mejorar el desempeño sísmico de las edificaciones empleando aisladores sin afectar la rentabilidad del proyecto.
Para ello, se evaluó aplicarlo en el proyecto “Residencial Hungría” el cual se trata de un edificio multifamiliar de 12 departamentos y 10 estacionamientos distribuidos en 4 pisos y un semisótano respectivamente.
Se modifico la configuración original del proyecto y se incluyó un sistema de aisladores de base con núcleo de plomo con el fin de comparar la rentabilidad entre ambos proyectos (Original y modificado con aisladores).
Los resultados obtenidos en la primera etapa muestran que ante un número reducido de pisos (04 pisos) la rentabilidad del proyecto modificado con aisladores es menor a la original, sin embargo, luego de evaluar múltiples opciones, se obtuvo que a partir de 07 pisos tiene un VAN de S/ 172,077 un TIR de 24 % mayor al COK que es de 20%.
Sabemos que en la Filosofía y Principios del Diseño Sismorresistente contenidos en la Norma E.030 del Reglamento Nacional de Edificaciones se reconoce que dar protección completa frente a todos los sismos no es técnica ni económicamente factible para la mayoría de las estructuras, es por ello por lo que el uso de los aisladores está enfocado principalmente a estructuras del sector salud y educación.
Con esto proyecto queremos propiciar la aplicación de aisladores a más proyectos de edificaciones y viviendas multifamiliares, verificando que, si puede ser rentable económicamente para el constructor, lo cual beneficiaría la demanda desatendida de la población que requiere una vivienda más segura y con mejor desempeño ante un sismo, y que minimice los costos de reparación, muertes y damnificados ante un eventual movimiento sísmico de alto impacto aun teniendo que invertir un porcentaje adicional en la compra del inmueble. / This research demonstrate that the seismic performance of buildings can be improved by using isolators without affecting the profitability of the project.
For this, it was evaluated in the "Residential Hungria" project, which is a multifamily building with 12 apartments and 10 parking spaces distributed in 4 floors and a semi- basement, respectively.
The original configuration of the project was modified and a system of base insulators with lead core was included in order to compare the profitability between both projects (Original and modified with insulators).
The results obtained in the first stage show that with a reduced number of floors (04 floors) the profitability of the project modified with insulators is lower than the original one, however, after evaluating multiple options, it was obtained that from 07 floors it have a NPV of S / 172,077 an IIR of 24% higher than the COK which is 20%.
We know the Philosophy and Principles of Earthquake Resistant Design contained in Standard E.030 of the National Building Regulations, it is recognized that providing complete protection against all earthquakes is not technically or economically feasible for most structures, which is why isolators is mainly focused on structures in the health and education sectors.
With this project we want to promote the application of insulators to more projects of buildings and multifamily housing, verifying that, it can be economically profitable for the builder, which would benefit the unattended demand of the population that requires a anti seismic building prepared for an earthquake, minimizes repair costs, deaths and victims in eventual high-impact seismic movement even having to invest an additional percentage in the purchase of the property. / Trabajo de investigación
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Radiative Effect of Mixed Mineral Dust and Biomass Burning Aerosol in the Thermal InfraredKöhler, Claas H. 13 December 2013 (has links)
This thesis treats the optical properties of mixed mineral dust and biomass burning aerosol in the thermal infrared (TIR) based on Fourier Transform infrared spectrometer (FTIR) measurements and radiative transfer simulations. The measurements were part of the Saharan Mineral Dust Experiment 2 (SAMUM-2) conducted from January to February 2008 at Praia, Cape Verde. The large amount of different instruments co-located at the main field site during the campaign resulted in a unique dataset comprising in-situ information and remote sensing data perfectly suited for column closure studies. The ultimate goal of this work is to investigate the consistency of microphysical and TIR remote sensing data. This is achieved by reproducing the measured radiances at top and bottom of the atmosphere (TOA, BOA) with a radiative transfer model, which assimilates the microphysical aerosol information gathered during SAMUM-2.
The first part of the thesis describes several experimental efforts, including a novel calibration method and a drift correction algorithm for the ground-based FTIR instrument operated within the scope of SAMUM-2 by the author. The second part introduces the concurrent radiative transfer library PIRATES, which has been developed in the framework of this thesis for the analysis of TIR aerosol optical properties. The third and final part of the treatise compares measured and simulated spectra for various typical scenarios encountered during SAMUM-2.
It is demonstrated in three case studies, that measured radiances in the TIR atmospheric window region (8-12 µm) can be reproduced at BOA and TOA by radiative transfer simulations assuming spheroidal model particles. Moreover,
spherical particles are shown to be an inadequate model for mineral dust aerosol
in this spectral region unless the aerosol optical depth is small.
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Surveillance of Host and Pathogen Derived Metabolites Activates Intestinal ImmunityPeterson, Nicholas D. 30 June 2022 (has links)
Intestinal epithelial cells function, in part, to detect infection with pathogenic organisms and are key regulators of intestinal immune homeostasis. However, it is not fully understood how intestinal epithelial cells sense pathogen infection and coordinate the induction of protective immune defenses. Here, we define two new mechanisms of innate immune regulation in a metazoan host.
First, we characterize the first bacterial pattern recognition receptor and its natural ligand in Caenorhabditis elegans. We show that the C. elegans nuclear hormone receptor NHR-86/HNF4 directly senses phenazine-1-carboxamide (PCN), a metabolite produced by pathogenic strains of Pseudomonas aeruginosa. PCN binds to the ligand-binding domain of NHR-86/HNF4, a ligand-gated transcription factor, and activates innate immunity in intestinal epithelial cells. In addition, we show that C. elegans NHR-86 senses PCN, and not other phenazine metabolites, as a marker of pathogen virulence to engage protective anti-pathogen defenses.
Second, we show that a phase transition of the C. elegans Toll/interleukin-1 receptor domain protein (TIR-1) controls signaling by the C. elegans p38 PMK-1 MAPK pathway. Physiologic stress, both P. aeruginosa infection and sterol scarcity, induce multimerization of TIR-1 within intestinal epithelial cells. Like the mammalian homolog of TIR-1, SARM1, oligomerization and phase transition of C. elegans TIR-1 dramatically potentiate its NAD+ glycohydrolase activity. TIR-1/SARM1 multimerization and NAD+ glycohydrolase activity are required for activation of C. elegans p38 PMK-1 pathway signaling and pathogen resistance.
These data uncover a mechanism by which nematodes interpret environmental conditions to prime innate immune defenses and promote survival in microbe rich environments. C. elegans animals augment these immune defenses by surveying for ligands specifically associated with toxigenic pathogens that are poised to cause disease. These findings define a new paradigm of intestinal immune control that informs the evolution of innate immunity in all metazoans.
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Investigation of Electromagnetic Wave Propagation Across Achiral-Chiral Interfaces and Fabry-Perot Type Slab Resonators Including Material Dispersion and Dielectric LossAtaai, Rajab Youssif S. 13 July 2022 (has links)
No description available.
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Méthodes variationnelles et topologiques pour l'étude de modèles non liénaires issus de la mécanique relativiste / Variational and topological methods for the study of nonlinear models from relativistic quantum mechanics.Le Treust, Loïc 05 July 2013 (has links)
Cette thèse porte sur l'étude de modèles non linéaires issus de la mécanique quantique relativiste.Dans la première partie, nous démontrons à l'aide d'une méthode de tir l'existence d'une infinité de solutions d'équations de Dirac non linéaires provenant d'un modèle de hadrons et d'un modèle de la physique des noyaux.Dans la seconde partie, nous prouvons par des méthodes variationnelles l'existence d'un état fondamental et d'états excités pour deux modèles de la physique des hadrons. Par la suite, nous étudions la transition de phase reliant les deux modèles grâce à la Gamma-convergence.La dernière partie est consacrée à l'étude d'un autre modèle de hadrons dans lequel les fonctions d'onde des quarks sont parfaitement localisées. Nous énonçons quelques résultats préliminaires que nous avons obtenus. / This thesis is devoted to the study of nonlinear models from relativistic quantum mechanics.In the first part, we show thanks to a shooting method, the existence of infinitely many solutions of nonlinear Dirac equations of two models from the physics of hadrons and the physics of the nucleus.In the second part, we prove thanks to variational methods the existence of a ground state and excited states for two models of the physics of hadrons. Next, we study the phase transition which links the models thanks to the $\Gamma$-convergence.The last part is devoted to the study of another model from the physics of hadrons in which the wave functions are perfectly confined. We give some preliminary results.
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