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Röös, Katja, and Jenny Hansdotter. "Scheduling modern elevators : A comparison of the two algorithms FSO and FS4." Thesis, KTH, Skolan för datavetenskap och kommunikation (CSC), 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-166717.
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Two of the most common elevator algorithms, FS4 and FSO, are discussed in this thesis. Their pros and cons regarding passenger waiting time and energy consumption are compared to find which of the algorithms perform best and what factors affect this. These topics are of interest for owners of modern building.By developing a simulation program the behavior of elevators controlled by these algorithms were simulated. Passenger pattern in the simulation was meant to emulate the pattern that occurs in office buildings at lunch hour.The conclusion is that due to differences in sector usage and specific rules for each algorithm they have different strengths concerning waiting time and energy consumption, but overall the FS4 is the stronger choice.
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Norberg, Erica. "Förstudie gällande dokumentering ochöverlämning av projekt vid fältenhetenshandläggare inom FSO och FSL." Thesis, Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-80320.
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Novák, Marek. "FSO vysílač/přijímač pro měření kvality spoje." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2016. http://www.nusl.cz/ntk/nusl-241051.
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Tato diplomová práce pojednává o zmírnění bitové chybovosti bezkabelového optického spoje s užitím principu reciprocity aplikovaného na komunikační kanál, spolu s možností kódování přenášených dat. V této práci je implementováno LDPC a Reed-Solomonovo kódování pro jejich vyhovující vlastnosti. Zbytková rámcová chybovost je vypočtena a k dispozici jako výstup systému, který je implementovaný v hradlovém poli (FPGA).
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Janík, Lukáš. "Podpůrný systém pro správu a řízení FSO transceiveru." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2016. http://www.nusl.cz/ntk/nusl-241040.
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Tato práce se zabývá problematikou optických bezkabelových spojů (FSO). V úvodní kapitole jsou diskutovány přednosti, základní principy a dílčí komponenty FSO spojů. Druhá kapitola se zabývá atmosférou z pohledu šířícího se optického svazku, jejím složením, základními veličinami a jevy v ní nastávajícími. V následující kapitole je popsáno několik metod ke zmírnění jevů majících negativní vliv na kvalitu spoje. Druhá část práce se zabývá návrhem podpůrného systému pro FSO, založeném na softcore mikroprocesoru MicroBlaze, návrhem jednoduchého síťového přepínače a síťového rozhraní. Závěr práce pojednává o implementaci webového serveru a tvorbě webové prezentace umožňující vzdálenou správu FSO a jeho komponent.
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He, Xiaohui. "Bit-interleaved coded modulation for hybrid rf/fso systems." Thesis, University of British Columbia, 2008. http://hdl.handle.net/2429/2868.
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In this thesis, we propose a novel architecture for hybrid radio frequency
(RF)/free–space optics (FSO) wireless systems. Hybrid RF/FSO systems
are attractive since the RF and FSO sub–systems are affected differently by
weather and fading phenomena. We give a thorough introduction to the RF
and FSO technology, respectively. The state of the art of hybrid RF/FSO systems
is reviewed. We show that a hybrid system robust to different weather
conditions is obtained by joint bit–interleaved coded modulation (BICM) of the
bit streams transmitted over the RF and FSO sub–channels. An asymptotic
performance analysis reveals that a properly designed convolutional code can
exploit the diversity offered by the independent sub–channels. Furthermore,
we develop code design and power assignment criteria and provide an efficient
code search procedure. The cut–off rate of the proposed hybrid system is also
derived and compared to that of hybrid systems with perfect channel state
information at the transmitter. Simulation results show that hybrid RF/FSO
systems with BICM outperform previously proposed hybrid systems employing
a simple repetition code and selection diversity.
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Kumar, Kuldeep. "Pulse Position Modulation using BICM-ID for FSO Channels." International Foundation for Telemetering, 2013. http://hdl.handle.net/10150/579510.
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ITC/USA 2013 Conference Proceedings / The Forty-Ninth Annual International Telemetering Conference and Technical Exhibition / October 21-24, 2013 / Bally's Hotel & Convention Center, Las Vegas, NVWe investigate pulse position modulation (PPM) and multipulse PPM (MPPM) for free space op- tical channels using bit interleaved coded modulation with iterative decoding. Data bits are first encoded by using a non recursive convolutional code and the coded bits after an interleaver are modulated before transmission. Iterative decoding is performed at the receiver. Optimized mapping is designed for MPPM. A genetic algorithm is used to find the optimized mapping for MPPM. Our simulation results show that a significant improvement in the error performance can be achieved by using optimized mapping and iterative decoding at the receiver.
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Kočvara, Pavel. "Měření mechanické stability budov a stožárů využívaných pro FSO spoje." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2015. http://www.nusl.cz/ntk/nusl-221236.
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The Master's thesis deals with the determination of measurement method of deflection the axis of the optical beam from its ideal position, which is caused by action of force of strong winds affecting the positional stability of the building or supporting structure (tower) used for placement of FSO links'heads. The thesis informs the readers about the other causes of deflection of beam axis in a real environment, about methods of determining the position of the beam axis in the plane perpendicular to the beam axis and the basic properties and parameters of the Gauss beams, including the phenomenon of diffraction on the output aperture of the laser transmitter.
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Barcík, Peter. "Optimální rozložení optické intenzity v laserovém svazku pro FSO komunikace." Doctoral thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2016. http://www.nusl.cz/ntk/nusl-256548.
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Dizertačná práca je zameraná na štúdium a analýzu rozloženia optickej intenzity v laserovom zväzku v rovine vysielacej (TXA) a prijímacej apertúry (RXA), ktorý podlieha zmenám ako pri šírení voľným priestorom, tak pri šírení atmosférou. Cieľom práce je nájsť optimálne rozloženie optickej intezity v rovine vysielacej apertúry, ktoré bude minimálne ovplyvnené apertúrou vysielača a atmosférickými turbulenciami. Za účelom analýzy šírenia optickej vlny atmosférou bola využitá simulácia založená na metóde Split-Step. Šírenie Flattened Gaussian zväzku bolo analyzované pre režim slabých a stredných turbulencií. Práca sa zaoberá použitím multimódového vlákna s veľkým priemerom jadra ako tvarujúceho elementu a obsahuje návrh refrakčného tvarovača, pomocou ktorého je možno konvertovať Gaussovský zväzok na zväzok s uniformným rozložením optickej intenzity. Nakoniec je pomocou získaných poznatkov zostavený plne fotonický vysielač a prijímač, ktorých použitie spočíva v generovaní a príjmaní optickej koherentnej vlny prenášajúcej presnú fázu.
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Ijaz, Muhammad. "Experimental characterisation and modelling of atmospheric fog and turbulence in FSO." Thesis, Northumbria University, 2013. http://nrl.northumbria.ac.uk/15255/.
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Free space optical (FSO) communication uses visible or infrared (IR) wavelengths to broadcast high-speed data wirelessly through the atmospheric channel. The performance of FSO communications is mainly dependent on the unpredictable atmospheric channel such as fog, smoke and temperature dependent turbulence. However, as the real outdoor atmosphere (ROA) is time varying and heterogeneous in nature as well as depending on the magnitude and intensity of different weather conditions, carrying out a proper link assessment under specific weather conditions becomes a challenging task. Investigation and modelling the ROA under diverse atmospheric conditions is still a great challenge in FSO communications. Hence a dedicated indoor atmospheric chamber is designed and built to produce controlled atmosphere as necessary to mimic the ROA as closely as possible. The experimental results indicate that the fog attenuation is wavelength dependent for all visibility V ranges, which contradicts the Kim model for V < 0.5 km. The obtained result validates that Kim model needs to be revised for V < 0.5 km in order to correctly predict the wavelength dependent fog attenuation. Also, there are no experimental data and empirical model available for FSO links in diverse smoke conditions, which are common in urban areas. Therefore, a new empirical model is proposed to evaluate the wavelength dependent fog and smoke attenuation by reconsidering the q value as a function of wavelength rather than visibility. The BER performance of an FSO system is theoretically and experimentally evaluated for OOK- NRZ, OOK-RZ and 4-PPM formats for Ethernet line data-rates from light to dense fog conditions. A BER of 10-6 (Q-factor ≈ 4.7) is achieved at dense fog (transmittance, T = 0.33) condition using 4-PPM than OOK-NRZ and OOK-RZ modulation schemes due to its high peak-to-average power ratio albeit at the expense of doubling the bandwidth. The effects of fog on OOK-NRZ, 4-PAM and BPSK are also experimentally investigated. In comparison to 4-PAM and OOK-NRZ signals, the BPSK modulation signalling format is more robust against the effects of fog. Moreover, the effects of using different average transmitted optical communication powers Popton the T and the received Q-factor using the OOK-NRZ modulation scheme are also investigated for light and dense fog conditions. The results show that for an FSO system operating at a Q-factor of 4.7 (for BER = 10-6), the required Q-factor is achieved at T of 48% under the thick fog condition by increasing Popt to 1.07 dBm, whereas the values of T are 55% and ~70% for the transmit power of 0.56 dBm and -0.7 dBm, respectively. The experimental characterisation and investigation of the atmospheric turbulence effect on the Ethernet and Fast-Ethernet FSO link is reported using different modulation schemes. The experiment is carried out in a controlled laboratory environment where turbulence is generated in a dedicated indoor atmospheric chamber. The atmospheric chamber is calibrated to mimic an outdoor turbulence conditions and the measured data are verified against the theoretical predictions. The experiment also demonstrates methods to control the turbulence levels and determine the equivalence between the indoor and outdoor FSO links. The results show that the connectivity of Ethernet and Fast-Ethernet links are highly sensitive to atmospheric turbulence. The results also show that the BPSK and OOK-NRZ modulation signalling formats are more robust against the weak atmospheric turbulence conditions than PAM signal.
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Aleixo, Júnior José Francisco Meireles 1977. "Modelagem experimental de um link FSO com inserção de feixes não difrativos." [s.n.], 2013. http://repositorio.unicamp.br/jspui/handle/REPOSIP/259686.
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Orientador: Michel Zamboni RachedDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Elétrica e de Computação
Made available in DSpace on 2018-08-22T08:06:38Z (GMT). No. of bitstreams: 1 AleixoJunior_JoseFranciscoMeireles_M.pdf: 4411350 bytes, checksum: bd00cad2cef3935ec7f463fc060d49c0 (MD5) Previous issue date: 2013
Resumo: Os objetivos centrais do presente trabalho foram a montagem de um link de comunicação óptica no espaço livre (FSO) e a posterior inserção de um feixe (nãodifrativo) de Bessel no enlace. Após uma breve revisão dos conceitos e limitações envolvidos no funcionamento dos sistemas FSO, construímos um enlace óptico chegando a uma distância de 50 metros a um custo muito reduzido. Na tentativa de diminuir o eventual impacto causado pela difração do feixe óptico, propusemos o uso de feixes não difrativos para realizar o link. Assim, após um estudo das características básicas do feixe nãodifrativo de Bessel e de sua geração experimental, realizamos sua inserção num enlace óptico de curta distância com o propósito de demonstrar a real possibilidade de uso desses feixes em comunicações ópticas no espaço livre
Abstract: The main aims of this work were building a link of free space optical communication (FSO) and the subsequent insertion of a Bessel (nondiffracting) beam in the link. After a brief review of the concepts about the operation and limitations of FSO systems, we build an optical link through a distance of 50 meters at a much reduced cost. Attempting to reduce the possible impact caused by the optical beam diffraction, and scattering we have proposed the use of nondiffracting beams to perform the link. In this way, after studying the basic characteristics of nondiffracting Bessel beams and their experimental generation, we implement their insertion in a short-distance optical link in order to demonstrate the real possibility of using these beams in free space optical communications
Mestrado
Telecomunicações e Telemática
Mestre em Engenharia Elétrica
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Alfowzan, Mohammed, Mehrdad Khatami, and Bane Vasic. "Optical Orbital Angular Momentum for Secure and Power Efficient Point-to-Point FSO Communications." International Foundation for Telemetering, 2013. http://hdl.handle.net/10150/579526.
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ITC/USA 2013 Conference Proceedings / The Forty-Ninth Annual International Telemetering Conference and Technical Exhibition / October 21-24, 2013 / Bally's Hotel & Convention Center, Las Vegas, NVWe address the problem of detection in orbital angular momentum (OAM). The focus of our analysis will be on the power efficient Q-ary Pulse Position Modulation (Q - PPM). Free space optical signals sent through wireless channels are degraded by atmospheric turbulence. In this paper a novel detection approach based on a factor graph representation of OAM Q-PPM signalling is presented to equalize for the crosstalk among orbital angular momentum vortices. It will be shown that our proposed detection algorithm significantly outperforms the separate detection scenario in terms of error rate performance.
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Oliveira, Guiomar Marins Justino de. "POLI-FOS: uma experiência de ensino-aprendizagem do francês com fins específicos na Escola Politécnica da USP." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/8/8146/tde-23112009-122427/.
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Esta dissertação de mestrado tem por objetivo apresentar, analisar e discutir a experiência de ensino de Francês Língua Estrangeira para estudantes da Escola Politécnica da USP, por meio do Programa CFI (Curso de Francês para Iniciantes). Tal formação, iniciada em 2001, foi concebida pelo Centro de Línguas da Faculdade de Filosofia, Letras e Ciências Humanas da Universidade de São Paulo a pedido da Comissão de Relações Internacionais da Escola Politécnica, e tinha por finalidade preparar os alunos que fossem fazer dois anos de curso em faculdades de engenharia francesas (Ecoles Polytechniques, Ecoles Centrales, Ponts et Chaussés, etc), no âmbito do Programa Duplo Diploma em Engenharia promovida pela Poli-USP. Nosso estudo corresponde ao período em que se decidiu discutir a progressão e o equilíbrio entre as duas modalidades de ensino trabalhadas - o Francês, Língua Estrangeira (FLE) geral e o Francês com Objetivos Específicos (FOS) - na formação dos estudantes, que passara de 2 para 3 anos, incluindo um módulo específico (Módulo France) e cujo número de inscritos havia chegado a quinhentos por semestre letivo. Nesse período, coube à equipe pedagógica a concepção geral do curso e a preparação do material didático de cada um dos seis módulos de ensino oferecidos, o que trouxe resultados bastante positivos, como mostram os questionários respondidos por alunos do Duplo Diploma que participaram de tal formação.The objective of this undergraduate thesis is to present, analyze and discuss the experience of teaching French as a foreign language for students at the Polytechnic School at University of São Paulo through the FCB Program (French Course for Beginners). This course, started in 2001, was designed by the Language Center at the College of Philosophy, Languages and Human Sciences of the University of São Paulo by request of the International Relations Commission of the Polytechnic School to prepare students who had been selected for the Dual Diploma Program in Engineering sponsored by Poli-USP, that is, a program in which students would spend two years of their undergraduate program at a French College of Engineering (Ecoles Polytechniques, Ecoles Centrales, Ponts et Chaussés, etc). Our study corresponds to the period in which we decided to reevaluate the progress and the balance between the two approaches used during the course general French as a Foreign Language (FFL) and French with Specific Objectives (FSO) a course which had increased from 2 to 3 years and which included a specific module (France module) and whose number of enrolled participants had reached 500 per semester. During this period, the pedagogical team (coordinators and teachers) were responsible for the general conception of the new course and for the textbooks of each one of the 6 teaching modules offered. The results obtained were extremely satisfactory as shown in the questionnaires answered by the Dual Diploma students who took this course.
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Alexander, Joshua L. "A Microcontroller-based, Optically-centric Communication System for Underwater Applications." University of Cincinnati / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1504868704379707.
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Gouveia, Fahim. "Projeto de um transceptor óptico para comunicação digital em espaço livre." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/3/3140/tde-04072007-133531/.
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Os sistemas de comunicação óptica por espaço livre, comumente denominados sistemas FSO (Free Space Optics), servem para estabelecer enlaces de comunicação do tipo wireless, ponto-a-ponto, a uma elevada taxa de dados e com alcances que podem variar de algumas centenas de metros a alguns quilômetros. O interesse pela tecnologia FSO tem sido estimulado pela necessidade de se fornecer soluções complementares às tradicionais (e.g. fibra óptica e RF) visando a atender à crescente demanda por conexões de banda larga. Algumas de suas aplicações mais importantes são a conexão de redes locais de computadores, a conexão de estações rádio base de telefonia móvel às centrais e o acesso de última milha. Embora a tecnologia FSO venha sendo empregada em pequena escala no Brasil, vislumbra-se o potencial de maior aplicação desta tecnologia em um futuro próximo, razão pela qual se propõe este estudo, focado no projeto de sistemas FSO. A principal contribuição deste trabalho é demonstrar uma possível solução para a realização de um enlace óptico operando em espaço livre, destinado a conectar duas redes locais de computadores Ethernet Rápida (100 Mbps). As seguintes atividades foram desenvolvidas: estudo das questões mais relevantes pertinentes ao projeto de sistemas FSO; projeto, construção e caracterização eletro-óptica de circuitos; montagem e demonstração do funcionamento de uma versão de testes do sistema, realizadas em laboratório; estudo de características associadas à transferência de radiação óptica de transmissor para receptor, envolvendo o balanço de potência para estimativa do alcance do enlace, sob condições atmosféricas ideais. Como resultado, obtivemos um sistema de comunicação do tipo full-duplex, operando no comprimento de onda de 850 nm em formato de modulação OOK, a uma taxa de dados efetiva de 125 Mbps. Com base na experiência obtida, melhoras ao sistema são sugeridas no final do trabalho.Free space optical communication systems (FSO systems) provide wireless, point-to-point communication links at high data rates, at maximum distances ranging from hundreds of meters to several kilometers. The growing interest in FSO technology arises from the necessity of providing complementary and alternative solutions to those already adopted (eg. fiber optics and RF), aiming to satisfy the increasing demand for broadband connections. Some of its most important applications are connecting local area networks (LANs), backhauling wireless networks and providing last mile access. Although today FSO is not widely adopted in Brazil, the technology has the potential for being adopted in a greater scale in the near future, which is the reason we propose a study focused on issues related to the design of FSO systems. This work\'s main contribution is to demonstrate a possible solution for the construction of a FSO system intended to connect two Fast Ethernet LANs (100 Mbps). For this purpose, the following activities were developed: study of the main aspects related to FSO system design; design, construction and electrooptical characterization of circuits; mounting and demonstration, in the lab, of a test version of the system; study of characteristics related to radiation transfer from transmitter to receiver, involving the use of the link power budget for an estimation of the maximum distance achievable under ideal atmospheric conditions. The result is a full-duplex communication system that employs the 850 nm wavelength in OOK modulation format, operating at an effective bit rate of 125 Mbps. Based on the knowledge achieved, improvements to the system are suggested at the end of this work.
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Dong, Yao, and Aminian Mohammad Sadegh. "Routing in Terrestrial Free Space Optical Ad-Hoc Networks." Thesis, Linköpings universitet, Kommunikations- och transportsystem, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-118572.
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Terrestrial free-space optical (FSO) communication uses visible or infrared wavelengths to broadcast high speed data wirelessly through the atmospheric channel. The performance of terrestrial FSO channel mainly depends on the local atmospheric conditions. Ad hoc networks offer cost-effective solutions for communications in areas where infrastructure is unavailable, e.g., intelligent transport system, disaster recovery and battlefield scenarios. Traditional ad hoc networks operate in the radio frequency (RF) spectrum, where the available bandwidth faces the challenge of rapidly increasing demands. FSO is an attractive alternative for RF in ad-hoc networks because of its high bandwidth and interference-free operation. This thesis investigates the influencing factors for routing traffic from given s-d pair while satisfying certain Quality of Services in terrestrial FSO ad hoc mesh networks under the effect of stochastic atmospheric turbulence. It starts with a comprehensive review of FSO technology, including the history, application, advantages and limitations. Subsequently the principle of operation, the building blocks and safety of FSO communication systems are discussed. The physics of atmosphere is taken into account to investigate how propagation of optical signals is affected in terrestrial FSO links. A propagation model is developed to grade the performance and reliability of the FSO ad hoc links in the network. Based on that model and the K-th shortest path algorithm, the performance of the path with highest reliability, the path with a second highest possible reliability and an independent path with no common links shared with the former two paths, were compared according to the simulation scenarios in node-dense area and node-sparse area. Matlab simulation shows that the short/long range dependent transmission delay are positively proportional to number of hops of the paths. Lower path reliability only dominate the cause of severe delay when traffic flow approaches near its upper link capacity in node-sparse area. In order to route traffic from given s-d pairs with satisfying certain Quality of Services, the path with highest reliability may not be the best choices since they may hold more hops which will degrade the QoS. Meanwhile, in case of exponential traffic congestion, it is recommended that both traffic demand and traffic flow propagating through the links should be pressed below a value close to the effective capacity, where the nonlinearity of the transmission delay curve starts to obviously aggravate.
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Luna, Ricardo, and Hrishikesh Tapse. "An Analysis on the Coverage Distance of LDPC-Coded Free-Space Optical Links." International Foundation for Telemetering, 2008. http://hdl.handle.net/10150/606240.
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ITC/USA 2008 Conference Proceedings / The Forty-Fourth Annual International Telemetering Conference and Technical Exhibition / October 27-30, 2008 / Town and Country Resort & Convention Center, San Diego, CaliforniaWe design irregular Low-Density Parity-Check (LDPC) codes for free-space optical (FSO) channels for different transmitter-receiver link distances and analyze the error performance for different atmospheric conditions. The design considers atmospheric absorption, laser beam divergence, and random intensity fluctuations due to atmospheric turbulence. It is found that, for the same transmit power, a system using the designed codes works over much longer link distances than a system that employs regular LDPC codes. Our analysis is particularly useful for portable optical transceivers and mobile links.
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Ringar, Octave. "Utilisation des techniques avancées d’Emission / Réception multi-antennes pour une transmission optique large bande." Thesis, Limoges, 2015. http://www.theses.fr/2015LIMO0100/document.
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Les systèmes de communication FSO sont des candidats potentiels pour de solutions de transmission spatiale à large bande. C’est pourquoi la présente thèse s’inscrit dans une contribution d’une nouvelle architecture de réseau FSO dans le cas d’une liaison de communication entre un satellite géostationnaire et une station terrienne. Elle traite aussi de l’influence de l’angle zénithal sur la qualité de la liaison optique en raison de la variation de la scintillation due à la complexité de l’atmosphère. Nous avons établi un nouveau canal de communication tenant compte de la subdivision de l’atmosphère en deux grandes zones de turbulence. Pour améliorer la performance de la liaison, nous avons d’abord placé un relais AF optiques ente le satellite et la station terrienne, ensuite nous avons introduit un paramètre construit `a partir de valeurs : p et 1-p. Le paramètre p correspond au ratio de la distance entre la station terrienne et le relais sur la distance de 36 000 Km correspondant a` l’orbite GEO. Dans notre cas, le relais est placé a 1000 Km a l’exosphère, le paramètre p = 1/36 et enfin la technique de diversité spatiale est appliquée en réception. Les résultats de simulation ont confirmé que les architectures des systèmes proposés sont meilleures que les performances de liaisons optiques directesFree space optical systems are potential candidates of large band spatial transmission solutions. In this thesis, FSO network architecture in the case of geo- stationary satellite to earth communication link is investigated and the influence of zenith angle on the quality of the link has been evaluated. Because of the variation of scintillation due to the complexity of the atmosphere, the optical space to earth communication link channel model has been developped. In order to overcome the main limitations of the prop- agation, optical relays with low earth orbit satellites and spatial diversity on earth could improve the link performance. To improve the link performance, an aggregated simulation model turbulence has been built based on parameters ”p” and ”1-p” introduced in the combined model a↵ecting the considered channels. The parameter ” p ” corresponds to the ratio of the distance from the earth to the relay over the total distance of 36 000Km. In the case of 1000 Km for a relay in the exosphere, p = 1/36. Simulation results show that the proposed network system architecture has outperformed the direct link performance
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Uzeir, Eduart. "Una rassegna delle tecnologie di comunicazione ottica senza fili." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2017. http://amslaurea.unibo.it/13271/.
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La tesi fa una panoramica delle tecnologie di comunicazione ottica, i principi di funzionamento, tecniche e strumenti utilizzati e possibili campi di applicazione. Nello specifico si esamina FSO, una tecnologia che opera nella banda delle frequenze a Infrarossi. VLC che opera nello spettro della luce visibile e UVC che opera con la luce Ultravioletta. Il terzo capitolo anlaizza LiFi, una tecnlogia che rappresenta l'evoluzione di VLC.
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Mata, Pedro José de Pinho. "Redes de acesso de próxima geração sobre meio ótico livre." Master's thesis, Universidade de Aveiro, 2014. http://hdl.handle.net/10773/13613.
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Mestrado em Engenharia Eletrónica e TelecomunicaçõesÓtica de meio livre, ou FSO como é mais conhecido, aparece como solução para grandes taxas de transferência de dados e maiores larguras de banda necessárias para as redes de comunicações sem fios. Sendo esta uma tecnologia flexível, eficaz e de baixo custo em relação às alternativas existentes no mercado, depressa despertou o interesse das empresas de telecomunicações. O FSO encontra-se em investigação há bastante tempo. Apesar de ainda existirem desafios que subsistem, o seu relevo leva à possibilidade de ser uma tecnologia complementar. Entre as dificuldades existentes encontram-se problemas de alinhamento entre transmissor e recetor e fenómenos atmosféricos que provocam atenuação e no pior dos casos perda da ligação. Ao longo desta dissertação, é feito o estudo de diferentes problemas presentes numa ligação FSO e analisado o comportamento de determinados sinais sobre a conexão. Para estes estudos foram aplicados vários sinais tais como NRZ e DP-QPSK e utilizada a tecnologia TWDM numa ligação FSO, analisando o seu desempenho. Para se analisarem situações onde a realização prática seria muito difícil, foram realizadas simulações, analisando BER, SER, EVM e Perdas do sistema FSO.
Free space optics or FSO as it is known, appears as a solution for large data rates and higher bandwidth needed for wireless networks. Since this technology is flexible, effective and low cost compared to existing alternatives in the market technology, quickly aroused the interest of telecommunications companies. The FSO is under investigation for quite some time. While there are still challenges that remain, their relief leads to the possibility of a complementary technology. Among the existing difficulties are problems of alignment between the transmitter and receiver, and atmospheric phenomena that cause attenuation and in the worst case loss of the connection. Throughout this dissertation, it’s done the study of different problems present in FSO connection and analyzes of the behavior of known signals upon the connection. For these studies, different signals like NRZ and DP-QPSK such as TWDM technology are applied and analyzed on a FSO link performance. To analyze situations where practical testing isn’t viable, simulations were used, analyzing BER,SER, EVM and losses of the FSO system.
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Kondicz, Dávid. "Optický přenos informací - bezpečnost přenosu." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2015. http://www.nusl.cz/ntk/nusl-220547.
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The submitted work deals with issues of optical transmissions and its security. We will become familiar with a variety of transferability of information, based on which we can assess the advantages and disadvantages of each technology as compared to optical information transmission. Based on acquired information we will try to implement interception of optical communication of cable TV provider.
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Sun, Xiaole, and Ivan B. Djordjevic. "Physical-Layer Security in Orbital Angular Momentum Multiplexing Free-Space Optical Communications." IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, 2016. http://hdl.handle.net/10150/615106.
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The physical-layer security of a line-of-sight (LOS) free-space optical (FSO) link using orbital angular momentum (OAM) multiplexing is studied. We discuss the effect of atmospheric turbulence to OAM-multiplexed FSO channels. We numerically simulate the propagation of OAM-multiplexed beam and study the secrecy capacity. We show that, under certain conditions, the OAM multiplexing technique provides higher security over a single-mode transmission channel in terms of the total secrecy capacity and the probability of achieving a secure communication. We also study the power cost effect at the transmitter side for both fixed system power and equal channel power scenarios.
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Kukshya, Vikas. "Wideband Terrestrial Path Loss Measurement Results For Characterization of Pico-cell Radio Links at 38 GHz and 60 GHz Bands of Frequencies." Thesis, Virginia Tech, 2001. http://hdl.handle.net/10919/33669.
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The advent of Internet based digital services, and bandwidth-intensive business and personal applications has necessitated deployment of broadband network access technologies. Research analysts project that the U.S. market for broadband wireless networking will grow to nearly $2 billion by 2004 and Local Multipoint Distribution Services (LMDS) have enormous potential to emerge as the most reliable and cost-effective solution. However, in order to design and deploy LMDS systems, it is vital for system designers to be able to predict the behavior of mm-waves (28, 38 and 60GHz) during different weather conditions, especially rain. This research attempts to characterize the performance of pico-cell scenario broadband wireless channels by measuring path loss statistics during different weather conditions.
Hardware and software components of a wideband direct-sequence spread spectrum (DSS) channel sounding system, used extensively throughout measurement campaigns, are discussed in detail in this dissertation. The measurement plan comprehensively describes the methodology, logistics, equipment setup, and calibration procedures for propagation measurement campaigns.
Power Delay Profile (PDP) snapshots recorded during measurement campaigns are thoroughly analyzed using the 'Channel Imaging Analysis Suite' and Path Loss as well as Rain Attenuation statistics, calculated from recorded PDP data files, are classified and tabulated on the basis of measurement locations, propagation frequencies and antenna polarizations. Path Loss Exponent values are also calculated and Rain Attenuation statistics are compared with popular rain models. Results from Frequency Diversity measurement campaigns are also presented.Master of Science
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Fulenwider, Thomas Edward. "Modular Laser Combat System for Remotely Operated Vehicles: Bridging the Gap Between Computer Simulation and Live Fire." DigitalCommons@CalPoly, 2010. https://digitalcommons.calpoly.edu/theses/335.
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In the emerging industry of small unmanned vehicles, pioneered by small businesses and research institutions, a suitable combat system test platform is needed. Computer simulations are useful, but do not provide the definitive proof of effective operation necessary for deployment of a combat system. What is needed is an affordable simulated weapons system that enables live flight testing without the used of live weaponry.
A framework is developed here for the construction of a simulated weapon using Free Space Optical (FSO) infrared communication. It is developed in such a way to ensure compatibility with a variety of platforms including ground and aerial vehicles, so that identical but configurable modules can be used on any vehicle that is to take place in a live combat simulation. A proof-of-concept implementation of this modular laser combat system framework is also presented and tested. The implemented system shows the value of such a simulated weapons system and future areas of improvement are also explored.
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Joseforsky, David C., and Gilbert O. Garcia. "Transformational communications architecture for the Unit Operations Center (UOC), Common Aviation Command and Control System (CAC2S), and Command and Control On-the-Move Network, Digital Over-the-Horizon Relay (CoNDOR)." Thesis, Monterey California. Naval Postgraduate School, 2004. http://hdl.handle.net/10945/1586.
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Approved for public release, distribution is unlimitedThe purpose of this research was to introduce a Transformational Communications Architecture for the Unit Operations Center (UOC); Common Aviation Command and Control System (CAC2S); and Command and Control On-the- Move Network, Digital Over-the-Horizon Relay (CoNDOR). The methodology used was to conduct Field Tests with government contractors and private vendors in order to demonstrate the capabilities of each wireless technology researched. These wireless technologies, Free Space Optics (FSO), Microwave, 802.16, 802.11b over SecNet-11, Orthogonal Frequency Division Multiplexing (OFDM), Broadband Satellite, INMARSAT, and Iridium, all have the potential of being implemented in the transformational communications architecture for intra-nodal and inter-nodal links for UOC and CAC2S, as well as the CoNDOR communications architecture. The ultimate goal of this research was to introduce different technologies that offer more flexibility, mobility, and capability at the tactical level giving the Marine Corps the tactical wireless edge. Throughout this research, the focus revolved around testing equipment and network configurations in an IP network. Special consideration was given to wireless issues for the UOC, CAC2S, and CoNDOR, which could improve line-of-sight, beyond line-of-sight, and over-the-horizon communications for each program. These new technologies will transform communications in the United States Marine Corps for the 21st century.
Captain, United States Marine Corps
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Meng, Ow Keong. "Study of wireless transmission protocol technology for use in flight line environment to assist the data uploading and downloading on aircraft." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2004. http://library.nps.navy.mil/uhtbin/hyperion/04Mar%5FMeng.pdf.
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Perera, Janaka P. "A low-cost man-portable free-space optics communication device for Ethernet applications." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2004. http://library.nps.navy.mil/uhtbin/hyperion/04Dec%5FPerera.pdf.
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Thesis (M.S. in Electrical Engineering)--Naval Postgraduate School, December 2004.Thesis advisor(s): Gamani Karunasiri, Xiaoping Yun. Includes bibliographical references (p. 47-50). Also available online.
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Chan, Chun Yip. "Friction stir processing of aluminium-silicon alloys." Thesis, University of Manchester, 2011. https://www.research.manchester.ac.uk/portal/en/theses/friction-stir-processing-of-aluminiumsilicon-alloys(0ffc1328-0a9d-4220-ab31-ee52173ed3a1).html.
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Friction Stir Processing (FSP) has the potential for locally enhancing the properties of Al-Si alloy castings, for demanding applications within the automotive industry. In this thesis, the effect of FSP has been examined on three different cast Al-Si alloys:i) A Hypoeutectic Al-8.9wt%Si Alloyii) A Hypereutectic Al-12.1wt%Si Alloyiii) A Hypereutectic Al-12.1wt%Si-2.4wt%Ni AlloyThe influence of different processing parameters has been investigated at a fundamental level. Image analysis of particle size distributions and growth method of tessellation were used to quantify the level of particle refinement and the homogeneity of the second phase spatial distribution. Stop-action experiments were also carried out, to allow the microstructural changes around the tool during FSP to be studied. Two computer models have been explored, in order to predict the temperature distribution and the material flow behaviour. Furthermore, the stability of the microstructure of the friction stir processed material was studied after being heat treated at elevated temperatures. The changes in particle size and grain structure were examined, hardness measurements were taken across the PZ, and tensile testing were carried out at room and elevated temperatures.After FSP, the microstructure of the cast Al-Si alloys was greatly refined. However, differences in microstructure have been observed throughout the PZ, which tended to be better refined and distributed on the advancing side, than the retreating side of the PZ. Changing the processing parameters also influenced the size and spatial distribution of the second phase particles. By studying the changes in microstructure around the tool from the stop-action experiments, and comparing the results to the thermal distribution and material flow behaviour predicted by the computer models, it has been shown that the flow stress, pitch, and temperature of processing, all needed to be considered, when determining the effects that FSP have on the microstructure. FSP caused very little changes to the hardness of the material, while tensile properties were greatly improved, due to the elimination of porosity and refinement of large flawed particles. In terms of the stability of the microstructure after FSP, particle coarsening and abnormal grain growth has been observed during high temperatures heat treatment. Furthermore, the Al2Cu phase was found to dissolve into solid solution at elevated temperatures, so GPZs and solute clustering can then develop within the alloy during natural ageing.
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Shehaj, Marinela. "Robust dimensioning of wireless optical networks with multiple partial link failures." Thesis, Compiègne, 2020. http://www.theses.fr/2020COMP2540.
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Cette thèse résume le travail que j’ai effectué dans le domaine de l'optimisation des réseaux optiques sans fil. Plus spécifiquement, l'objectif principal de ce travail est de proposer des algorithmes efficaces de dimensionnement de réseau pour assurer la satisfaction du trafic dans un réseau qui subit des pannes partielles de liens (par exemple lorsque certains liens et/ou nœuds sont opérationnels avec une capacité réduite) causés principalement par les conditions météorologiques. Le critère principal pour déterminer l'efficacité des algorithmes proposés est le coût de dimensionnement du réseau tout en maintenant la satisfaction du trafic à des niveaux élevés. Les domaines d'application principale que nous avons à l'esprit sont les réseaux qui utilisent le Free Space Optics (FSO) - une technologie de transmission optique sans fil à large bande où les liens de communication sont assurés au moyen d'un faisceau laser envoyé de l'émetteur au récepteur placé en ligne droite. Les réseaux FSO présentent plusieurs avantages (comme le coût peu élevé, la facilite d'installation, la grande capacité de transmission, etc.), mais le plus grand inconvénient est la vulnérabilité des liens FSO face aux conditions météorologiques, causant une perte substantielle de la puissance de transmission sur le canal optique. Cela rend le problème de dimensionnement du réseau important et difficile. Par conséquent, une approche appropriée du dimensionnement du réseau FSO devrait tenir compte de ces pertes afin que le niveau du trafic transporté soit satisfaisant dans toutes les conditions météorologiques observées. Dans cette thèse, nous avons étudié et développé une telle approche. Dans la première partie de la thèse, nous introduisons un premier problème de dimensionnement, qui a pour objectif d’être le plus général possible et inclue les contraintes les plus importantes. Nous présentons ensuite un algorithme d'optimisation robuste pour ce problème de dimensionnement. Pour construire notre approche, nous commençons par définir un ensemble de défaillances des liens, dit de référence, qui utilise les données météorologiques d’une période donnée pour laquelle le réseau doit être protégé. Ensuite, nous formulons mathématiquement le problème de dimensionnement robuste de réseau qui utilise l'ensemble des pannes de liens ci-dessus. Pourtant, cet ensemble des pannes de référence obtenu contiendra, dans la plupart des cas, un nombre excessif d'états et en même temps ne contiendra pas tous les états qui apparaîtront potentiellement dans le futur. Par conséquent, nous proposons d'approximer cet ensemble par un type spécial d'ensemble de défaillances des liens virtuel (dite ensemble d’incertitude), appelé K-set et paramétré par une valeur entière K, où K est inférieur ou égal au nombre de tous les liens du réseau. Pour un K donné, le K-set contient tous les états du réseau correspondant à toutes les combinaisons de K, ou moins, des liens affectés simultanément. Dans certains cas, il y a des situations où la météo est extrêmement mauvaise et pour lequel nous proposons de construire un modèle de réseau hybride composé de liens FSO et de liens de fibre optique terrestre. La deuxième partie de cette thèse est consacrée à l'amélioration de l’approximation de l’ensemble des pannes de référence via des ensembles de d'incertitude (ou poly-topes d'incertitude). Dans la première partie, nous avons présenté l'idée de K-sets des liens. Maintenant, nous étendons cela en considérant les dégradations simultanées de K nœuds (ce qui signifie la dégradation de tous les liens adjacents)This thesis summaries the work we have done in optimization of wireless optical networks. More specifically, the main goal of this work is to propose appropriate network dimensioning algorithms for managing the demand and ensuring traffic satisfaction in a network under partial link failures (i.e. when some links and/or nodes are operational with reduced capacity) caused mostly by weather conditions. The primary criterion in deciding the efficiency of the proposed algorithms for the network is the dimensioning cost of the network while keeping the traffic satisfaction at high reasonable levels. The main application area we have in mind are the networks that apply Free Space Optics (FSO) - a well established broadband wireless optical transmission technology where the communication links are provided by means of a laser beam sent from the transmitter to the receiver placed in the line of sight. FSO networks exhibit several important advantages but the biggest disadvantage is vulnerability of the FSO links to weather conditions, causing substantial loss of the transmission power over optical channel. This makes the problem of network dimensioning important, and, as a matter of fact, di cult. Therefore, a proper approach to FSO network dimensioning should take such losses into account so that the level of carried traffic is satisfactory under all observed weather conditions. In this thesis, we firstly describe such an approach. In the first part of the thesis, we introduce a relevant dimensioning problem and present a robust optimization algorithm for such enhanced dimensioning. To construct our approach we start with building a reference failure set which uses a set of weather data records for a given time period against which the network must be protected. Next, a mathematical model formulation of the robust network dimensioning problem uses the above failure set. Yet, such obtained reference set will most likely contain an excessive number of states and at the same time will not contain all the states that will appear in the reality. Hence, we propose to approximate the reference failure set with a special kind of virtual failure set called K-set parameterized by an integer value K, where K is less than or equal to the number of all links in the network. For a given K, the K-set contains all states corresponding to all combinations of K, or less, simultaneously affected links. Sometimes, there are situations where the weather is extremely bad and what we propose is to build a hybrid network model composed of FSO and fiber links. The second part of this thesis is devoted to the improvement of the so-called uncertainty sets (or uncertainty polytopes). In the first part we have introduced the idea of link Ksets. Now we extend this by considering simultaneous degradations of K nodes (meaning degradation of all adjacent links). Finally, inspired by the hitting set problem a new idea was to find a large number of subsets of two or three affected links and to use all possible combinations (composed of 2 or at most 3 of this subsets) to build a new virtual failure set that covers as much as possible the reference failure set that we got from the study of real weather data records. Next, this new failure set will serve as input for our cut-generation xxi algorithm so that we can dimension the network at a minimum cost and for a satisfactory demand realization. A substantial part of the work is devoted to present numerical study for different network instances that illustrates the effectiveness of the proposed approach. A dedicated space is given to the construction of a realistic network instance called Paris Metropolitan Area Network (PMAN)
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Sekkiou, Imene. "Design of communication systems based on broadband sources for fiber and free space optical links." Doctoral thesis, Universitat Politècnica de València, 2021. http://hdl.handle.net/10251/172542.
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[ES] Las comunicaciones ópticas inalámbricas (OWC) constituyen una tecnología muy prometedora para el desarrollo de futuras comunicaciones inalámbricas. De hecho, ha despertado un interés creciente entre los investigadores y varias empresas de todo el mundo trabajan actualmente en el desarrollo de redes inalámbricas de muy alta velocidad. Las comunidades científica e industrial consideran la OWC como una tecnología complementaria en sus diversas formas: comunicaciones ópticas en el espacio libre (FSO), comunicaciones de luz visible (VLC) o fidelidad de la luz (Li-Fi). El espectro óptico ha sido considerado durante muchos años como una gran oportunidad para las comunicaciones inalámbricas, especialmente debido a la saturación del espectro de radiofrecuencia (RF).
Esta disertación trata del uso de fuentes de banda ancha en sistemas de transmisión de luz visible (VLC), así como en sistemas de transmisión en el espectro infrarrojo por fibra óptica. En el trabajo de investigación realizado se pueden distinguir tres partes:
En la primera parte, se considera el estudio y la simulación de componentes de Diodos Emisores de Luz (LED) con el software WIEN2k centrándose en las propiedades ópticas y eléctricas de los elementos II-VI.
La segunda parte trata del diseño, la implementación y las pruebas de diferentes prototipos de comunicación VLC para la transmisión analógica y digital en modo simplex y semidúplex. Hemos demostrado un sistema OWC empleando una fuente de banda ancha (LED) para la transmisión no sólo de datos, sino también para la transmisión inalámbrica de energía. Además, se aborda el problema de la sincronización y la detección del nivel "1" o "0" de un bit en los sistemas de comunicación inalámbrica óptica implementados que surge como consecuencia de la atenuación de la luz a lo largo de la distancia y al problema de la pérdida de línea de visión (NLOS) entre el emisor y el receptor. Para hacer frente a este problema, se ha proporcionado un protocolo de comunicación que garantiza la transmisión fiable de datos digitales con un algoritmo de detección de nivel de bits adaptativo y se ha demostrado su eficacia mediante la transmisión de textos e imágenes.
Además, esta tesis aporta una solución para la implementación de transmisores multiplexados en redes con división de longitud de onda (WDM) para formatos de modulación con multiplexación por división de frecuencia ortogonal (OFDM) basados en el uso de fuentes de banda ancha en el espectro infrarrojo para redes de fibra bidireccionales centralizadas. A pesar de las limitaciones impuestas por la dispersión cromática en el uso de este tipo de fuentes ópticas, la inclusión de ciertas estructuras antes de la detección permite la transmisión de señales OFDM en enlaces ópticos. En este trabajo se ha demostrado experimentalmente la reutilización de portadoras, la asignación dinámica de ancho de banda y la transmisión de señales OFDM multibanda mediante el uso de fuentes ópticas de banda ancha en redes WDM.
Los principales resultados obtenidos en cada parte de esta tesis doctoral muestran los procedimientos de estudio, la eficacia de las soluciones propuestas y las limitaciones encontradas.[CA] Les comunicacions òptiques sense fils (OWC) constitueixen una tecnologia molt prometedora per al desenvolupament de futures comunicacions sense fils. De fet, ha despertat un interés creixent entre els investigadors i diverses empreses de tot el món treballen actualment en el desenvolupament de xarxes sense fils de molt alta velocitat. Les comunitats científica i industrial consideren la OWC com una tecnologia complementària en les seues diverses formes: comunicacions òptiques en l'espai lliure (FSO), comunicacions de llum visible (VLC) o fidelitat de la llum (Li-Fi). L'espectre òptic ha sigut considerat durant molts anys com una gran oportunitat per a les comunicacions sense fils, especialment a causa de la saturació de l'espectre de radiofreqüència (RF). Aquesta dissertació tracta de l'ús de fonts de banda ampla en sistemes de transmissió de llum visible (VLC), així com en sistemes de transmissió en l'espectre infraroig per fibra òptica. En el treball de recerca realitzat es poden distingir tres parts: ¿ En la primera part, es considera l'estudi i la simulació de components de Díodes Emissors de Llum (LED) amb el software WIEN2k centrant-se en les propietats òptiques i elèctriques dels elements II-VI. ¿ La segona part tracta del disseny, la implementació i les proves de diferents prototips de comunicació VLC per a la transmissió analògica i digital de manera simplex i semidúplex. Hem demostrat un sistema OWC emprant una font de banda ampla (LED) per a la transmissió no sols de dades, sinó també per a la transmissió sense fil d'energia. A més, s'aborda el problema de la sincronització i la detecció del nivell "1" o "0" d'un bit en els sistemes de comunicació sense fil òptica implementats, que sorgeix a conseqüència de l'atenuació de la llum al llarg de la distància i al problema de la pèrdua de línia de visió (NLOS) entre l'emissor i el receptor. Per a fer front a aquest problema, s'ha proporcionat un protocol de comunicació que garanteix la transmissió fiable de dades digitals amb un algorisme de detecció de nivell de bits adaptatiu i s'ha demostrat la seua eficàcia mitjançant la transmissió de textos i imatges. ¿ A més, aquesta tesi aporta una solució per a la implementació de transmissors multiplexats en xarxes amb divisió de longitud d'ona (WDM) per a formats de modulació amb multiplexació per divisió de freqüència ortogonal (OFDM) basats en l'ús de fonts de banda ampla en l'espectre infraroig per a xarxes de fibra bidireccionals centralitzades. Malgrat les limitacions imposades per la dispersió cromàtica en l'ús d'aquest tipus de fonts òptiques, la inclusió d'unes certes estructures abans de la detecció permet la transmissió de senyals OFDM en enllaços òptics. En aquest treball s'ha demostrat experimentalment la reutilització de portadores, l'assignació dinàmica d'amplada de banda i la transmissió de senyals OFDM multibanda mitjançant l'ús de fonts òptiques de banda ampla en xarxes WDM. Els principals resultats obtinguts en cada part d'aquesta tesi doctoral mostren els procediments d'estudi, l'eficàcia de les solucions proposades i les limitacions trobades.
[EN] Optical wireless communication (OWC) is a very promising technology for future wireless communications developments. It has attracted increasing interest from researchers and several companies around the world are currently working on the development of very high-speed wireless networks. The scientific and industrial communities believe that OWC will be a complementary technology in its various forms: Free Space Optical communications (FSO), Visible Light Communications (VLC), Light Fidelity (Li-Fi). In fact, the optical spectrum has been considered for many years as a great opportunity for wireless communications especially due to the saturation of the radio frequency (RF) spectrum. This dissertation deals with the use of broadband sources in visible light transmission systems (VLC) as well as fiber optic systems. To carry out the research, three parts can be distinguished: In the first part, we consider the study and simulation of Light Emitting Diode (LED) components with the WIEN2k software by focusing on the optical and electrical properties of elements II-VI. The second part deals with the design, implementation and testing of different VLC communication prototypes for analog and digital transmission in simplex and half-duplex mode. We have demonstrated that an OWC system using a broadband source (i.e. an LED) can be used not only for data transmission, but also for wireless power transmission. Moreover, the synchronization problem and the detection of level "1" or "0" of a bit often arise in the optical wireless communication systems. This is a result of the attenuation nature of the light over the distance and the problem of Non Line-Of-Sight (NLOS) between the emitter and the receiver. To deal with this problem, a communication protocol ensuring reliable digital data transmission with an adaptive bit level detection algorithm has been provided and its effectiveness has been demonstrated by the transmission of texts and images. In addition, this thesis provides a solution for the implementation of wavelength division multiplexed - orthogonal frequency division multiplexed (WDM-OFDM) transmitters based on the use of broadband sources in the infrared spectrum for centralized bidirectional fiber networks. Despite the chromatic dispersion that avoids the use of this type of optical sources, the inclusion of certain structures before detection allows the transmission of OFDM signals in optical links. Carrier reuse, dynamic bandwidth allocation and multiband OFDM signals transmission will be experimentally demonstrated by using optical broadband sources in WDM networks. The main results obtained during this thesis work demonstrate the study procedures, for each part, the effectiveness of the proposed solutions as well as the constraints encountered.
Sekkiou, I. (2021). Design of communication systems based on broadband sources for fiber and free space optical links [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/172542
TESIS
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Floyd, Colette F. "Subcutaneous FSH implants." Connect to this title online, 2007. http://etd.lib.clemson.edu/documents/1193080537/.
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Alebrahim, Sharifa. "Generation of viable «fro/fro» mice and analyses of their mineralized tissue." Thesis, McGill University, 2014. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=123248.
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Sphingomyelin phosphodiesterase 3 (SMPD3), a plasma membrane-bound enzyme, cleaves sphingomyelin to generate ceramide and phosphorylcholine. These two bioactive lipid metabolites regulate many cellular activities. A recessive mutation called fragilitas ossium (fro) in the Smpd3 gene leads to impaired bone and tooth mineralization in the fro/fro mice. Most fro/fro mice do not survive beyond the perinatal period that makes it difficult to get enough number of mice for the phenotypic analyses. Our specific aims are: 1) Generate viable fro/fro mice on a C57BL/6-C3H/HeN mixed background to analyze their tooth mineralization defects; and 2) Generate viable fro/fro mice on a pure C57BL/6 background by transient expression of Smpd3 during late embryonic development, and characterize their skeletal phenotype. We observed an improved survival of the fro/fro mutants on the C57BL/6-C3H/HeN mixed background. Examination of the teeth of these mixed background-mutants revealed a delayed mantle dentin mineralization and consequently, a delay in enamel mineralization. These tooth abnormalities progressively improved with time. The restoration of Smpd3 expression driven by a Col1a1-Smpd3 transgene in the odontoblasts corrected the tooth mineralization defects in fro/fro;Col1a1-Smpd3 mice. In order to obtain viable fro/fro mice on the C57BL/6 background, we followed a strategy based on the Tet-On inducible gene expression system. Following a complex breeding strategy, we generated fro/fro;ROSA-rtTA;TRE-Smpd3 compound mutant mice. The ubiquitous ROSA promoter drives the expression of rtTA transactivator in these mice. When treated with doxycycline, TRE-Smpd3 expression was induced in the cells synthesizing the rtTA protein in the compound mutants. The doxycycline treatment given to the pregnant mothers during the late gestation period resulted in the correction of the limb deformities and the skeletal mineralization defects in fro/fro;ROSA-rtTA;TRE-Smpd3 embryos. However, induction of Smpd3 expression in the adolescent fro/fro;ROSA-rtTA;TRE-Smpd3 mice was not sufficient to correct the defects in trabecular bone mineralization and the impaired growth of the long bones. This novel mouse model will be a useful tool to study SMPD3 biology in vivo.La sphingomyéline phosphodiestérase 3 (Smpd3) code pour enzyme liée à la membrane plasmique qui clive la sphingomyéline et génère du céramide et de la phosphorylcholine. Ces métabolites lipidiques bioactifs jouent un rôle important dans de nombreuses activités cellulaires. Une mutation autosomique récessive du gène smpd3 est à l'origine du modèle murin fragilitas ossium (fro). Cette mutation est associée à une altération de la minéralisation des os et de la matrice extracellulaire des dents chez les souris fro/fro. De plus, ces souris sont de plus petites tailles et ont un taux élevé de mortalité périnatale, ce qui rend difficile l'obtention d'un nombre suffisant de souris pour l'analyse phénotypique. Nos objectifs étaient de 1) augmenter le taux de survie des fro/fro souris et de caractériser les défauts de minéralisation des dents, et 2) générer un modèle fro/fro sur un fond génétique pur C57BL/6 par l'expression transitoire de Smpd3 au cours du développement embryonnaire tardif. Normalement, aucune fro/fro souris sur le fond C57BL/6 ne survit au-delà de la période périnatale. Cependant, nous avons observé une meilleure survie des fro/fro mutants sur le fond mixte C57BL/6-C3H/HeN. De plus, L'examen des dents de ces derniers a révélé un retard dans la minéralisation du manteau dentinaire et, par conséquent, un retard dans la minéralisation de l'émail. Mais, ces anomalies dentaires se sont progressivement améliorées avec le temps. Par contre, la restauration de l'expression de Smpd3 contrôlée par le transgène Col1a1-Smpd3 dans les odontoblastes a corrigé les défauts de minéralisation des dents des souris fro/fro;Col1a1-Smpd3. Afin d'obtenir des souris viables fro/fro sur le fond C57BL/6, nous avons suivi une stratégie basée sur le système d'expression génique inductible Tet-On et sur une méthode complexe de sélection pour générer des souris fro/fro;ROSA-rtTA;TRE-Smpd3 double mutants. Dans ce système, l'expression du TRE-Smpd3 sera induite par l'activation du transactivateur rtTA sous le contrôle du promoteur ubiquitaire ROSA par la Dox uniquement dans les cellules synthétisant la protéine rtTA. Après avoir traité les souris gestantes avec de la Dox, les embryons fro/fro;ROSA-rtTA;TRE-Smpd3 ont montré une minéralisation normale et une correction des membres déformés vers la fin de la gestation. Bien que les niveaux d'expression inductible de Smpd3 dépendaient de la dose de la Dox, aucune dose administrée n'a été suffisante pour complétement sauver les défauts de minéralisation de l'os ou le retard de croissance des os longs chez les adultes fro/fro;ROSA-rtTA;TRE-Smpd3. L'analyse du profil d'expression des gènes suggère que l'expression inductible de TRE-Smpd3 n'était pas assez forte pour pouvoir corriger les anomalies du squelette chez les souris adultes fro/fro;ROSA-rtTA;TRE-Smpd3.
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Serpa, Luiz Felippe Santos Perret. "Fio a fio – como as professoras do Projeto Salvador tecem suas formações." Faculdade de Educação, 2014. http://repositorio.ufba.br/ri/handle/ri/18420.
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Esse estudo tem como objeto a formação das professoras que cursaram Pedagogia no Projeto Salvador, uma iniciativa da Prefeitura Municipal de Salvador e a Faculdade de Educação da UFBA. Pretende analisar as narrativas escritas no gênero memorial de formação, trabalho final do curso, tomando como base como pensam sua própria formação e como entendem o “ser professor” na contemporaneidade. Para tal, o estudo se inspirou nas perspectivas autobiográficas (SOUZA e ABRAHÃO, 2006; SOUZA, 2006; NÓVOA, 2007; FERREIRA, FISCHER e PERES, 2009; ABRAHÃO, 2010; SOUZA, 2011) relativas aos aportes teórico-metodológicos; também se apoiou nas concepções de narrativas e memoriais de formação (BENJAMIN, 1987; BELTRÃO, 2005; ARAPIRACA, 2007; PRADO e SOLIGO, 2007; FERREIRA, FISCHER e PERES, 2009; CORDEIRO e SOUZA, 2010; SARTORI, 2010; BARBOSA e PASSEGGI, 2011a; BARBOSA e PASSEGGI, 2011b) e demais noções acerca da razão sensível (MAFFESOLI, 1998), da concepção de leitura e literatura (LARROSA 2002, 2004), entre outros autores, para dialogar com as narrativas das professoras que foram coletadas seguindo os eixos “eu-estudante”, “eu-professora” e “eu-professora no curso de formação”. A perspectiva de análise se pautou na prioridade de cada memorial de formação como uma enunciação, como acontecimento, de modo que se buscou o entendimento de cada narrativa singularmente, seguindo como ponto da análise as marcas linguísticas que comprovaram a leitura desenvolvida nesses estudos, inspirando-se na perspectiva discursiva de análise. Buscou-se não estabelecer uma generalização, porém as narrativas foram cruzadas para a composição de um tecido, o do Projeto Salvador. Os estudos apontaram para uma necessidade de aprofundamento nas coletas e estudos das narrativas, visando captar os processos de pensamento, de sensação, de ação, de relação a que se submetem as professoras e seus saberes, aqueles que não se cristalizam, são fugazes, mas oferecem oportunidades de atuação para outros mestres. A formação pensada como desequilíbrio foi o que ficou patente nesse estudo, considerando que ao desequilibrar-se, a pessoa tende a buscar modos de manter-se no estado de equilíbrio.
ABSTRACT This paper studied the formation of the teachers who attended the Pedagogy Projeto Salvador, one of the City initiative of Salvador and the School of Education at UFBA. Intends to analyze the narratives written in the formation of memorial gender, final course work, based on how they think their own training and they understand the "being a teacher" nowadays. To this end, the study was inspired by the autobiographical perspective (SOUZA and ABRAHÃO, 2006; SOUZA, 2006; NÓVOA, 2007; FERREIRA, FISCHER and PERES, 2009; ABRAHÃO, 2010; SOUZA, 2011) concerning the theoretical and methodological contributions; also based on the concepts of narratives and memorials training (BENJAMIN, 1984; BELTRÃO, 2005; ARAPIRACA, 2007; PRADO and SOLIGO, 2007; FERREIRA, FISCHER and PERES, 2009; CORDEIRO and SOUZA, 2010; SARTORI, 2010; BARBOSA and PASSEGGI, 2011a; BARBOSA and PASSEGGI, 2011b) and other notions about sensible reason (MAFFESOLI, 1998), the design of reading and literature (LARROSA 2002, 2004), among other authors, to dialogue with the narratives of the teachers that were collected following the axis "i-student", "I-teacher" and "I-teacher in the training course". The prospect of analysis was based on the priority of each training as a memorial enunciation, as an event, so we sought to understand each uniquely narrative, following as a point of analysis the language tags that proved the reading developed in these studies, inspirando- in the discursive analysis perspective. We tried to not make a generalization, but the narratives were crossed for the composition of a tissue, the Projeto Salvador. The studies pointed to a need to strengthen the collection and study of narratives, in order to capture the processes of thought, feeling, action in relation to undergoing the teachers and their knowledge, those who do not crystallize, are fleeting, but provide performance opportunities for other teachers. The training was designed as unbalanced as demonstrate
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Lima, Sandra Mara Maciel de. "No fio da sutura." reponame:Repositório Institucional da UFPR, 2009. http://hdl.handle.net/1884/19941.
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Sousa, André Lima. "Fortaleza por um fio." Florianópolis, SC, 2011. http://repositorio.ufsc.br/xmlui/handle/123456789/95519.
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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Filosofia e Ciências Humanas, Programa de Pós-Graduação em Geografia, Florianópolis, 2011Made available in DSpace on 2012-10-26T02:55:42Z (GMT). No. of bitstreams: 1 294796.pdf: 9040370 bytes, checksum: 422adbc7827d65885f49e6b5ee6bff8e (MD5)
Buscou-se com esta dissertação de mestrado, realizar uma análise dialética do desenvolvimento urbano da metrópole de Fortaleza, na qual foi assumido como "fio condutor" do estudo a busca pela compreensão da constituição do "ser social" naquela metrópole. Para tanto, foram consideradas três dimensões do desenvolvimento urbano: a expansão, a degeneração e a transição. O objeto de análise foi o chamado "espaço de transição", cujos elementos foram identificados por meio da investigação da experiência do Movimento dos Conselhos Populares (MCP) entre os anos 2000 e 2011 - intervalo no qual foi possível identificar e formular uma proposta de periodização dessa experiência. Concluiu-se que foi possível constatar, por intermédio da análise desse movimento popular, elementos que podem indicar o surgimento de uma formação sócio-espacial de novo tipo, um vir a ser de inspiração pós-capitalista.
En este ensayo se ha buscado realizar un análisis dialéctico del desarrollo urbano de la metrópoli de Fortaleza, teniendo como hilo conductor de la investigación la búsqueda por la comprensión de la constitución del "ser social" en aquella metrópoli. Para eso, fueron consideradas tres dimensiones del desarrollo urbano: la expansión, la degeneración y la transición. El objeto de la investigación fue el "espacio de transición", cuyos elementos fueron identificados en la investigación empírica del Movimento dos Conselhos Populares MCP en los años de 2000 hasta 2011 intervalo en lo cual fue posible identificar y formular una propuesta de periodización de esta experiencia. En la conclusión, fue posible constatar, a través del análisis de este movimiento popular, elementos que pueden indicar el surgimiento de una formación socio-espacial de nuevo tipo, una posibilidad futura de superación del capitalismo.
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Wilson, Timothy Craig. "The role of mRNA stability and Fos protein in transient c-fos mRNA accumulation." Thesis, University of Cambridge, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.304567.
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Opsahl-Vital, Sibylle. "Etude de l'ostéogenèse imparfaite et de la dysplasie dentinaire chez la souris FRO/FRO." Paris 5, 2006. http://www.theses.fr/2006PA05M003.
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La mutation fragilitas ossium (fro), découverte en 1975 lors d'une étude de mutagenèse chimique chez la souris, conduit à une forme sévère d'ostéogenèse imparfaite. Dans la majorité des cas ce syndrome résulte d'atteintes moléculaires de l'un des deux gènes codant pour le collagène de type 1. Cependant dans 10 à 15% des cas, aucune anomalie du collagène n'est détectée et il s'agit alors d'une forme non-collagénique de la maladie. La souris fragilitas ossium est actuellement l'unique modèle animal existant pour l'étude de ces formes non-collagéniques de ostéogenèse imparfaite. Une approche de clonage positionnel a permis d'identifier le gène causal de la mutation. Il s'agit du gène Smpd3 codant pour la sphingomyélinase neutre 2 (nSMase2). Chez les mutants, la protéine présente une large délétion de 1758 bp entraînant un remaniement de la partie terminale, avec notamment la perte d'une histidine nécessaire à l'activité catalytique de la protéine. Ceci a pour conséquence la perte de l'activité enzymatique chez les souris fro/fro. Les enzymes et métabolites de la voie sphingomyéline/céramide interviennent dans de nombreux mécanismes de signalisation, ainsi que dans la régulation de processus cellulaires majeurs tels que la prolifération cellulaire, l'apoptose ou encore la minéralisation, et sont impliqués à différents niveaux dans la formation des tissus osseux et dentaires. L'étude du phénotype dentaire, chez les animaux adultes mutants, a mis en évidence un volume pulpaire réduit, consécutif à une oblitération de type dentinaire et une hypercémentose au niveau des racines des molaires. Ces éléments sont assez semblables à ceux retrouvés dans les cas de dysplasie dentinaire humaine. Notre travail à également permis de mettre en évidence les nombreuses répercussions au niveau des protéines de la matrice dentinaire, notamment celles de la famille des SIBLINGS. L'hypominéralisation et le retard de la croissance constatés chez les animaux nouveau-nés peuvent être corrélés à la perturbation de la voie sphingomyéline/céramide. L'étude de ce modèle animal permet une amélioration dans la compréhension des processus de formation et de minéralisation de la matrice dentaire et notamment le rôle joué par les lipides. Ces travaux ouvrent également des perspectives en matière de thérapie génique pour les formes non-collagéniques d'ostéogenèse imparfaiteThe fragilitas ossium (fro) mutation was discovered in 1975 in mice after treatment of spermatocytes with a chemical mutagen tris (1-aziridinyl). This recessive mouse mutation leads to a syndrome of severe osteogenesis imperfecta with no detectable collagen defect. The effects of the mutation are also detected in teeth. The size of the incisors, the density of the network of trabeculate in the alveolar bone, formation and mineralization in the dentin are clearly different in fro/fro and wild type mice. In the molar, dentine filled a residual pulp chamber, a situation close to some forms of dentin dysplasia. Genetic mapping of the fro locus led us to focus on Smpd3, the gene encoding nSMase 2 a neutral sphingomyelinase, We identified a large deletion at the 3 end of the smpd3 coding frame that led to aberrant C-terminal protein sequence and to complete loss of enzymatic activity. As an intracellular enzyme, Smpd3 is involved both in cell proliferation and in apoptosis. The effect on proliferation may be an indirect cause of the alterations seen in the fro/fro mouse. As an extracellular enzyme, Smpd3 may be directly implicated in matrix sphingomyelin catabolism, a lipid found in dental. Altogether, adding these data to what we have observed in the fro/fro mutation in dental tissues and in mandibular and long bone as well, we suggest that proper sphingomyelin metabolismn is essential for mineralization in bone and dentin. To the best of our knowledge, the fro/fro mice provide the very first in vivo experimental evidence that sphingomyelin and moreover sphingomyelin degradation plays a crucial role in bone and dentin mineralization
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Andersson, Christoffer, and Daniel Ahl. "Fluid Structure Interaction: Evaluation of two coupling techniques." Thesis, Högskolan i Halmstad, Sektionen för Informationsvetenskap, Data– och Elektroteknik (IDE), 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-16050.
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This thesis concerns one of the upcoming and well discussed subjects withincalculations these days, namely how to perform an analysis of the interactionbetween fluid and structure, called FSI (Fluid Structure Interaction). In the report,evaluations of two different methods of simulating FSI are done. These are knownas Practical FSI (P-FSI) and Direct Coupled FSI (DC-FSI). The methods aredeveloped by Acusim in cooperation with Simulia and the softwares used areAbaqus and AcuSolve.The first part of the thesis is dedicated to explain the general theory and thegoverning equations for FSI. After the general explanation a more delimitatedexplanation regarding P-FSI and DC-FSI are given. After this we show how tosetup and perform the couplings regarding which parameters that need to bedefined and how to perform the analyses using Abaqus and AcuSolve.The last section of the thesis covers the evaluation process. We started withevaluating the methods against a benchmark problem where we compared thecalculation time and accuracy regarding displacements and frequencies. The nextthing we evaluated was how different numbers of modes used in the P-FSIcoupling affects the result. The last thing we evaluated was the robustness of themethods using different mass densities of the structure and different time-stepsizes.The result of the evaluation regarding the criteria: accuracy, calculation time androbustness showed that the P-FSI method is the most efficient method comparedto DC-FSI regarding FSI problems when the structural response is linear.
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Krapp, Andreas, Ulrich Schiefele, Klaus Peter Wild, and Adolf Winteler. "Der „Fragebogen zum Studieninteresse" (FSI)." Universität Potsdam, 1993. http://opus.kobv.de/ubp/volltexte/2009/3360/.
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Die vorliegende Arbeit berichtet über die Entwicklung des „Fragebogen zum Studieninteresse" (FSI) und seine testtheoretische Überprüfung. An der Untersuchung nahmen 298 Studenten verschiedener Studiengänge teil. Ausgehend von einer 27 Items umfassenden Version verblieben aufgrund von Faktorenanalyse und Rasch- Skalierung 18 Items, die eine eindimensionale Skala bilden. Die interne Konsistenz (Alpha) des revidierten FSI beträgt .90, die Test-Retest-Reliabilität .67 (Zeitspanne: 2 Jahre). Zur Prüfung der Validität des revidierten FSI wurde eine Reihe weiterer Variablen erhoben (z.B. intrinsische motivationale Orientierung, Tätigkeitszentrierung, Extraversion, Verwendung von Lernstrategien, Studienleistung). Die Ergebnisse zeigen, daß der FSI in ausreichendem Maße konvergente, diskriminante und kriteriumsbezogene Validität besitzt.This article reports the development of the "Study Interest Questionnaire" (SIQ). A total of 298 university students took part in a study that was designed to test the reliability and validity of the SIQ. The original version of the SIQ included 27 items. On the basis of factor and Rasch analyses we obtained a unidimensional version consisting of 18 items. The revised version of the SIQ showed considerable internal consistency (Alpha = .90) and test-retest reliability (.67; time lag: 2 years). In order to test the convergent, discriminant, concurrent, and predictive validity of the SIQ, a number of additional variables were assessed (e.g., intrinsic motivational orientation, extraversión, use of learning strategies, achievement). The results confirm that the SIQ is a sufficiently valid instrument.
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Sutherland, Jacqueline Anderson. "The transactivation functions of Fos." Thesis, University of Cambridge, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.309211.
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Robertson, Jean-Baptiste. "Finite FSS for long wavelengths." Thesis, University of Kent, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.544052.
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Gargulák, Karol. "Finančná analýza Fio banky, a.s." Master's thesis, Vysoká škola ekonomická v Praze, 2017. http://www.nusl.cz/ntk/nusl-359429.
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The aim of this thesis is a financial analysis of Fio bank during the years from 2011 to 2015. The thesis is divided into four parts. The first part deals with financial analysis itself, its objectives, limitations, and used indicators. The second part consists of basic information about Fio bank, its brief history, and introduction of two competitive banks. Bank sector is characterized in the third part. Financial analysis of Fio bank is performed in the last part. For higher complexity, results of Fio bank are compared with results of two other competitors, Equa bank and Air bank. At the end of the thesis, results of the analysis are summarized together with assessment of the bank´s financial situation.
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Vilela, Ana Lucia Oliveira. ""Lamber o fio da gilete"." Florianópolis, SC, 2011. http://repositorio.ufsc.br/xmlui/handle/123456789/95051.
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Tese (doutorado) - Universidade Federal de Santa Catarina, Centro de Filosofia e Ciências Humanas. Programa de Pós-Graduação em História.Made available in DSpace on 2012-10-25T20:03:45Z (GMT). No. of bitstreams: 1 298796.pdf: 4686933 bytes, checksum: efe7a6194c7357b87a10a34c649b7428 (MD5)
Que pode acontecer quando se coloca a obra de Hélio Oiticica em fricção com os dispositivos de poder? Essa é a aventura a que nos propusemos na pesquisa que redundou nesta tese. Buscou-se, assim, do atrito de algumas das obras de Oiticica com dispositivos de poder, identificar estratégias, táticas, modos de operação de resistência.
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Dobiášková, Veronika. "Strategie rozvoje podniku FPO s.r.o." Master's thesis, Vysoké učení technické v Brně. Fakulta podnikatelská, 2010. http://www.nusl.cz/ntk/nusl-222495.
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This diploma thesis is dealing with creating compact description of strategic documentation in a company. It helps to set one direction, where the company should be heading in its vision, function, identity, objectives and values. It is a compact collection for strategic development of the company and for keeping the direction towards the chosen objectives set beforehand. It is possible to secure coordination and mutual belonging of the parts and objective of the company in a framework of unanimous material.
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Sory, Issa. ""Ouaga la belle !" gestion des déchets solides à Ouagadougou : enjeux politiques, jeux d'acteurs et inégalités environnementales." Paris 1, 2013. http://www.theses.fr/2013PA010523.
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En 2005, les autorités municipales de la capitale burkinabé (Ouagadougou) ont entrepris, avec le soutien de la Banque mondiale, l'application d'un schéma de gestion des déchets afin de réorganiser cette filière. La ville a ainsi été dotée de centres intermédiaires de collecte et d'un centre d'enfouissement, de traitement et de valorisation des déchets. L'espace urbain a été subdivisé en douze territoires de pré-collecte. Ceux-ci ont été concédés, suite à un appel d'offres, aux groupements d'intérêt économique et aux petites et moyennes entreprises. Ouagadougou est aussi reconnue au niveau international. Elle est, à travers la Brigade Verte – une association municipale de balayage des rues - , lauréate de plusieurs prix : prix Africités en 2003, Dubaï International en 2006 et Bahreïn International en 2008. Les réformes de la filière permettent aux autorités municipales de positionner Ouagadougou à l' « avant-garde » de la gestion des déchets dans la sous région ouest africaine et l'attribution des distinctions internationales sert de support à la construction d'une image officielle de Ouagadougou : « Ouaga la belle ». En conservant cette « ville vitrine » imaginaire à la réalité ouagalaise, cette thèse met en exergue les enjeux politiques de l'assainissement de l'environnement urabain à Ouagadougou. Dans la filière des déchets, ces enjeux participent au maintien d'un service de collecte à la fois « partagé » et « disputé ». Ensuite, les jeux de pré-collecteurs remettent en cause la philosophie véhiculée par le schéma : la persistance d'un « système composite », l'effacement des limites des territoires de pré-collecte et la fin du concept de « quartier propre ». Enfin, les réformes du système de gestion des déchets – par les choix techniques, la répartition spatiale des centres de collecte et des logiques des pré-collecteurs – permettent d'observer une inégalité d'accès au service de collecte et une discrimination sociale quant à l'exposition aux nuisances liées aux déchets à « Ouaga la belle ».
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Biehler, Alexandra. "Enjeux et modes de constitution des espaces publics à Ouagadougou (Burkina Faso)." Paris 1, 2010. http://www.theses.fr/2010PA010513.
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Cette thèse se propose d'aborder les modes de constitution des espaces publics à Ouagadougou. La capitale burkinabè connaît depuis les années 2000 une série d'évènements qui accélèrent les mutations urbaines: un projet urbain ambitieux pour le centre-ville qui entraîne la délocalisation de quelques 12500 habitants et donne à l'État l'occasion de diffuser de nouvelles normes urbaines; l'installation de la présidence et d'une nouvelle zone administrative dans le sud de la ville qui donne à Ouagadougou une double centralité ; l'incendie du Grand marché qui modifie non seulement la vie de nombreuses familles, mais aussi les parcours urbains quotidiens de tous les Ouagalais. Ces événements sont l’occasion d’observer les rapports ville-État dans la gestion de la capitale, lieu de confrontation et d’interaction entre la population et le pouvoir, dont l’histoire nous révèle le rôle prépondérant du politique dans sa construction. Ils sont aussi l’occasion, conjointement à l’étude de six zones de la capitale et de leur paysage, d’étudier les pratiques et les représentations qu’ont les citadins de la ville, leurs modes d’habiter, les facteurs d’évolution de leur appréhension de la cité et de la construction collective des espaces de vie. Nous avons mis en évidence l’importance de la valeur de l’espace urbain habitée dans la construction des identités citadines, et nous avons montré combien les mutations urbaines et sociales en cours pouvaient être propices au processus de citadinisation des habitants de la ville et aussi à l’émergence d’espaces publics.
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Friderich, Marie Lorraine Aubrège Alain. "La relation soignant-soigné au Burkina Faso en 2008 Comment les professionnels et les patients la perçoivent-elles ? /." [S.l.] : [s.n.], 2009. http://www.scd.uhp-nancy.fr/docnum/SCDMED_T_2009_FRIDERICH_MARIE_LORRAINE.pdf.
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Revault, Pascal. "Serpents, savoirs et santé chez les Mossi : prise en charge des envenimations par Echis ocellatus en Afrique soudano-sahélienne à travers l'exemple du plateau ouagalais." Paris 13, 1994. http://www.theses.fr/1994PA130034.
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Sawadogo, Ram Christophe. "Bâani : étude d'une collectivité intervillageoise des marches septentrionales du pays moogli au Burkina." Paris 5, 1985. http://www.theses.fr/1985PA05H047.
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Yaogo, Maurice. "Pratiques de soins et faits de développement : le cas des itinéraires thérapeutiques dans la région de Bagré (Burkina Faso)." Paris, EHESS, 2002. http://www.theses.fr/2002EHES0131.
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Ce travail est consacré aux pratiques de soins, selon une lecture pluridimensionnelle, à partir de plusieurs études de cas. Les différentes approches donnent un éclairage sur les demandes locales de soins et les réponses thérapeutiques variées qui sont proposées en fonction des contextes de maladie et de nombreux référents d'ordre cognitif ou matériel. A partir de l'exposé et l'analyse d'un cas de maladie et des recours thérapeutiques sollicités, des caractéristiques saillantes des itinéraires thérapeutiques sont décrites dans une visée critique. Cette appoche diachronique est complétée par une approche transversale des faits locaux de santé : premièrement, par une analyse fine, mise en contexte linguistique, des usages thérapeutiques traditionnels, biomédicaux ou d'ordre syncrétique; deuxièmement, à travers une description des enjeux liés aux actions et interactions dans le champ de la santé, avec une ouverture sur des théorisations d'ordre épistémologique.
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Sévédé-Bardem, Isabelle. "Précarités juvéniles et individualisme à Ouadougou : étude des pratiques et des représentations des jeunes adultes en situation de précarité." Paris 1, 1994. http://www.theses.fr/1994PA010503.
Full textAbstract:
À travers l'étude des pratiques et des représentations des jeunes adultes de Ouagadougou en situation de précarité sont mis en évidence des processus d' individualisation qui apparaissent comme un des éléments fondamentaux de la modernité urbaine africaine. Deux champs sociaux sont privilégies : celui de la entre les sexes et celui des itinéraires professionnels de la débrouillardiseIndividialization processes are inderscored through the study of pratices and representations of ouagadougou young adults in precariouss situation. These processes appear to be one of the basic elements of african urban modernity. Tho social fields are favoured : realations between sexes and smartness professional intinenaries