Thèses sur le sujet « A demonstration experiment »

This thesis demonstrates the standard for the design of an experimental model to be used for numerical validation purposes. It is proposed that numerical models may be assessed more accurately and directly by validation with a completely described experimental model, consisting of accurate descriptions of the operating conditions, fluid properties, and experimental uncertainties. This idea is demonstrated using an experimental model of a swirling jet at three Reynolds numbers (Re = 550, 2560, and 3650), with vortex breakdown existing in the higher two Reynolds number cases. Measurements of the swirling jet were obtained at two locations upstream of the jet exit with the intent to provide the flow profiles to the numerical model and four downstream locations used to assess the accuracy of the model. Numerical simulations using the laminar model and k-e, k-w, and k-e-v^2-f turbulence models were used for turbulence closure. Detached Eddy Simulation (DES) and Reynolds-stress model results were also obtained to demonstrate unsteady numerical solutions. The results of the experimental and numerical models are compared to understand the influence on validation using a completely described experimental model.

Thesis (M.S. in Space Systems Operations)--Naval Postgraduate School, Sept. 2001.
Thesis advisors, Panholzer, Rudy ; Sakoda, Dan. "September 2001." Includes bibliographical references (p. 69-70). Also available in print.

Up to now, short-wavelength free-electron lasers (FEL) have been systems on the scale of hundreds of meters up to multiple kilometers. Due to the advancements in laser-plasma acceleration in the recent years, these accelerators have become a promising candidate for driving a fifth-generation synchrotron light source – a lab-scale free-electron laser. So far, demonstration experiments have been hindered by the broad energy spread typical for this type of accelerator. This thesis addresses the most important challenges of the conceptual design for a first lab-scale FEL demonstration experiment using analytical considerations as well as simulations. The broad energy spread reduces the FEL performance directly by weakening the microbunching and indirectly via chromatic emittance growth, caused by the focusing system. Both issues can be mitigated by decompressing the electron bunch in a magnetic chicane, resulting in a sorting by energies. This reduces the local energy spread as well as the local chromatic emittance growth and also lowers performance degradations caused by the short bunch length. Moreover, the energy dependent focus position leads to a focus motion within the bunch, which can be synchronized with the radiation pulse, maximizing the current density in the interaction region. This concept is termed chromatic focus matching. A comparison shows the advantages of the longitudinal decompression concept compared to the alternative approach of transverse dispersion. When using typical laser-plasma based electron bunches, coherent synchrotron radiation and space-charge contribute in equal measure to the emittance growth during decompression. It is shown that a chicane for this purpose must not be as weak and long as affordable to reduce coherent synchrotron radiation, but that an intermediate length is required. Furthermore, the interplay of the individual concepts and components is assessed in a start-to-end simulation, confirming the feasibility of the envisioned experiment. Moreover, the setup tolerances for a first demonstration experiment are determined, confirming the general practicability. The revealed challenges, besides the energy spread, especially concern the source stability and the precision of the beam optics setup.

Arbetet syftar till att ge exempel på hur konstruktivismen kan användas praktiskt genom olika arbetssätt inom fysikundervisningen i den svenska gymnasieskolan. Arbetssätten som tas upp är demonstrationsexperimentet, den induktiva och den deduktiva klassrumslaborationen, hemlaborationen samt problemlösningen. För vart och ett av dessa arbetssätt ges ett exempel i konstruktivistisk anda, som så vitt upphovsmännen vet, inte tidigare har använts i detta sammanhang. Några av arbetssätten har testats i undervisning av upphovsmännen och därefter utvärderats.

Bakalauro dabą „Elektros srovės, geometrinės optikos, atomo branduolio fizikos mokomieji bandymai ir jų loginė analizė“ susideda iš įvado, 3 skyrių, išvadų ir 28 literatūros šaltinių. Darbo apimtis 66 puslapiai. Pirmoje ir antroje dalyje apžvelgiama pedagogikos ir psichologijos literatūros šaltinių analizė. Trečioje dalyje yra aprašomi XII klasės fizikos kurso mokomieji bandymai ir jų loginės samprotavimo schemos iš: • Elektros srovės (9 eksperimentai). • Geometrinės optikos (8 eksperimentai). • Atomo branduolio fizikos (5 eksperimentai). Samprotavimo schemos planai padeda mokiniams: suprasti demonstracinio bandymo esmę, nustatyti priežasties – pasekmės ryšius ir priklausomybę, gretinti sąlygas ir išvadas, apibendrinti rezultatus, daryti išvadas.
Bachelor's work „Educational Experiments of Electric Current, Geometrical Optics, Atomic Nuclear Physics and Their Logical Analysis” consists of an introduction, 3 chapters, conclusions and 28 references. Working amount 66 pages. In first and second part gives an overview of pedagogy and psychology analysis of literature source. In third part is described education experiments of physics and their logical reasoning schemes of XII class from: • Electric Current (9 experiments). • Geometrical Optics (8 experiments). • Atomic Nuclear Physics (5 experiments). Reasoning schemes help students to: understand the nature of the demo task, determine cause – effect relationships and dependencies, compare conditions and findings, summarize the results, do conclusions.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
This study presents the development of the Product – In the strings of musical instruments – and analysis of its application. Basically, the Product is a set to study mechanical waves through experiments and the use of musical instruments, both created with alternative material which is easily available. The product aids the teacher and comprises: text with approach to the physical concepts worked in the classroom; texts supporting teacher’s work and texts supporting students’ work, unit plans and lesson plans; manuals guiding the apparatuses assembly and their use in the classroom. This proposal contains 08 (eight) sessions, distributed into 12 (twelve) lessons, which seek, from a teaching sequence, to approach wave basic concepts and develop those concepts at the high school level aiming at providing advances to the teachinglearning process regarding the students involved. In such elaboration, the activities were based on Ausubel’s learning theorie. Finally, from the Product use and analysis, it was seen that the sequence of lessons given made it possible to enhance the study of mechanical waves through strings, and the activities with musical instruments and experiments developed in the classroom provided the students better interaction with the content worked, since these practices motivated them to inquire and observe in their own context the physics content being studied. Therefore, the product application, through a differentiated practice, resulted in advances to the learning-teaching process in a meaningful manner.
No presente trabalho são apresentados o desenvolvimento do Produto Nas cordas dos instrumentos musicais – e análise de sua da aplicação. Em linhas gerais o Produto é um conjunto para o estudo de ondas mecânicas a partir de experimentos e instrumentos musicais, ambos confeccionados com materiais alternativos e de fácil acesso. Basicamente, o Produto é um material de apoio ao professor e contém: texto com abordagem dos conceitos físicos trabalhados em sala de aula; textos de apoio ao professor e textos de apoio aos educandos; planejamento de unidade e planos de aula; manuais de montagem dos aparatos e utilização destes em sala de aula. Nesta proposta foram planejadas 08 (oito) seções, distribuídas em 12 (doze) aulas, as quais buscam, a partir de uma sequência didática, abordar os conceitos básicos de ondulatória e efetuar a devida transposição dos conceitos em nível de ensino médio a fim de proporcionar avanços no processo de ensino-aprendizagem por parte dos educandos. Nesta elaboração, as atividades foram fundamentadas na teoria de aprendizagem de Ausubel. Por fim, da aplicação do Produto e posterior análise, constatou-se que a sequência de aulas realizadas possibilitou contemplar o estudo das ondas mecânicas por meio de cordas, sendo que as atividades dos instrumentos musicais e experimentos em sala de aula proporcionaram uma melhor interação dos educandos com os conteúdos trabalhados porque tais práticas instigaram os mesmos a perguntar e a observar em seu próprio contexto a física abordada. Assim, a aplicação do produto proporcionou, por meio de uma prática diferenciada, avanços no processo de ensino-aprendizagem de uma forma significativa.

General relativity describes gravity as the curvature of space-time. The theory predicts the existence of gravitational waves (GWs), which can be described as ripples in space-time propagating at the speed of light. So far no direct detection of GWs has been achieved. The sensitivities of the currently leading laser interferometric GW detectors are limited by various noise sources, i.e. seismic, thermal, shot noises etc. Several conceptual studies are underway investigating new techniques that aim to improve sensitivities enough to fulfil the requirements of the next generation of detectors. One of these new techniques under investigation is displacement and frequency noise free interferometry (DFI). This thesis reports on the experimental demonstration of a new method of partial DFI that is effective in the GW detection frequency band. The isolation of a mimicked GW signal from displacement noise of one mirror is demonstrated for a detuned Fabry-Perot cavity. A significant reduction in the displacement noise of the cavity input mirror was achieved by properly combining the reflected and transmitted signals from the cavity. This result represents the first experimental demonstration of this recently proposed DFI scheme, and lays the foundations for future work aimed at implementing DFI schemes in up-coming laser interferometric GW detectors.

Thesis (B.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1986.
MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING
by Wilbert L. Blake, Jr.
B.S.

Current research on cognitive learning is applied to the designing of several experiments for use in high school physical science and physics classes. The goal of the project was to use simple inexpensive materials to construct experiments and demonstrations that illustrate physics concepts and can easily be modeled using simple mathematics.Saline solutions are used to show simple examples of refraction and effects of a solution of varying density. The refractive index of two liquids is measured. The continuous refraction of a stratified fluid is demonstrated. Fluid flow is investigated. This leads to a simple experiment that leads to an easy way to measure the acceleration of gravity.The goal was met with several simple experiments using inexpensive materials, modeling techniques, and simple mathematics derivations were designed and tested. Data from the experiments gives results that are very close to the accepted values.
Department of Physics and Astronomy

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Nuclear Engineering, 2005.
Includes bibliographical references (p. 107-112).
Recently, it has been suggested that an array of small quantum information processors sharing classical information can be used to solve selected computational problems, referred to as a type-II quantum computer. The first concrete implementation demonstrated here solves the diffusion equation, and it provides a test example from which to probe the strengths and limitations of this new computation paradigm. The NMR experiment consists of encoding a mass density onto an array of 16 two-qubit quantum information processors and then following the computation through 7 time steps of the algorithm. The results show a good agreement with the analytic solution for diffusive dynamics. From the numerical simulations of the NMR implementations, we explore two major error sources (1) the systematic error in the collision operator and (2) the linear approximation in the initialization. Since the mass density evolving under the Burgers equation develops sharp features over time, this is a stronger test of liquid state NMR implementations of type-II quantum computers than the previous example using the diffusion equation. Small systematic errors in the collision operator accumulate and swamp all other errors. We propose, and demonstrate, that the accumulation of this error can be avoided to a large extent by replacing the single collision operator with a set of operators, that have random errors and similar fidelities.
(cont.) Experiments have been implemented on 16 two-qubit sites for eight successive time steps for the Burgers equation. The improvement in the experimental results suggests that more complicated modulation of error terms may offer further improvement. An alternative approach has been suggested to encode in the Fourier space (k-space) to remove the usage of this linear approximation. This new method also provides us a simple means to implement the streaming operation quantum mechanically by controlling magnetic field gradients sandwiched with RF pulses. Therefore, this method might serve as a new tool to probe the implementations of quantum lattice gas (QLG) algorithms. Experimental demonstration of the diffusion equation has been performed on 16 two-qubit sites for four successive time steps. Recently, much attention has been focused on constructing many identical simple processing elements arranged in a cellular automata architecture recently. It is likely that the early quantum hardware will be built in a similar manner. Quantum lattice gas algorithms therefore provide a bridge between such hardware and potential early algorithms. We propose a quantum lattice gas model similar to the one proposed by Margolus for the classical setting.
(cont.) This quantum algorithm simulates the one-particle quantum random walk. The preliminary experimental design associated with the lattice gas model on a ring molecule is presented. The searches for the suitable pulses to construct the unitary operators, used in the implementations of the lattice gas model, are done and the results are encouraging.
y Zhiying Chen.
Ph.D.

The present study attempted to establish a flashing or solid red light as a surrogate conditioned motivating operation (CMO-S) by pairing the light with the unconditioned motivating operation (UMO) of heat. The effects of the red light were assessed by an ABAB reversal design for three participants and an ABA reversal design for one participant. Baseline sessions consisted of presenting the red light in the absence of the UMO of heat to assess for any behavioral effects of the red light before and after pairing with the UMO of heat. Galvanic Skin Response (GSR) was recorded for all participants as an indirect measure of sweating. Additional dependent variables and the ambient temperature for each participant’s UMO of heat were identified through a temperature and response assessment. The additional dependent variable was drinking water for Participants 2–4 and throat clearing for Participant 1. Results suggest that the flashing red light may have been conditioned as a CMO-S for Participants 2 and 3. Participant 4 did not consume any water during any baseline session, suggesting that the solid red light did not function as a CMO-S after pairing. Results for Participant 1 suggests that throat clearing was controlled by additional unknown variables and was not evoked by the UMO of heat. Results potentially supporting the CMO-S should be interpreted cautiously given study limitations involving temperature control and the extent that the UMO of heat was clearly demonstrated for each participant.

The goal of this project was to create an intuitive and clear demonstrator of the dening properties of quantum mechanics using single slit diraction of light, which has quantum mechanical properties because of light's waveparticle duality. In this report we will describe the process and thoughts behind our project of creating a portable demonstration of the uncertainty principle. By designing and building both a physical setup with a laser, a slit, mirrors, lenses, beam-splitters, attenuators and cameras, and developing software which displays images from the cameras in a clear user interface with calculations we hope that students from high schools and gymnasiums that visit Vetenskapens Hus at Alba Nova will learn something new while using the demonstrator.

The World Wide Web provides the capability of delivering multi-media presentations to a wide audience. This thesis details the design and development of the site Psychoacoustical demonstrations and experiments at McGill University: it discusses site organization, selection of materials and development methods. In order to evaluate the utility of the site, site usage data, feedback from readers and data from experiments are analyzed and discussed. The thesis examines the success of the site in attracting a wide audience and holding its attention, as course material, in gathering data from psychoacoustical experiments, and in obtaining feedback from readers. Suggestions for future sites of this type are included.
The test of the thesis should be read in conjunction with experiencing the World Wide Web site at http://www.music.mcgill.ca/auditory/Auditory.html.

In the late 19th and early 20th centuries famous scientists like Boltzmann, Loschmidt, Maxwell and Einstein tried, unsuccessfully, to find the link between the time-reversible equations of motion of individual molecules and irreversible thermodynamics. The solution to this puzzle was found in 1993, and the link is now known as the Fluctuation Theorem (FT). In the decade that followed theory and computer simulation tested the FT and, in 2002, an experiment indirectly demonstrated the FT.¶ This thesis describes original experiments that demonstrate the FT directly using Optical Tweezers. A related expression, known as the Kawasaki Identity, is also experimentally demonstrated. These experimental results provide a rigorous demonstration that irreversible dynamics can be obtained from a system with time-reversible dynamics.

The subject of this thesis covers the process of online parameter estimation of agile satellites. Accurate knowledge of parameters such as moment of inertia and centre of mass play a crucial role in satellite attitude control and pointing performance. Typically, identification of parameters such as these is performed on-ground using post-processing algorithms. This thesis investigates the potential of performing the identification procedures in real-time on-board operating satellites, using only measurements available from typical satellite attitude sensors.    The thesis covers the areas of system identification and modelling of spacecraft attitude dynamics. An algorithm based on the Unscented Kalman Filter is developed for online parameter estimation of spacecraft moment of inertia parameters. The proposed method is successfully validated, both through simulation environments, and in practice using Airbus’ satellite hardware demonstrator INTREPID, a three-axis air-bearing table equipped with CMG actuators and typical attitude sensors.

[EN] The present PhD thesis deals on the model, design and experimental demonstration of Arrayed Waveguide Grating (AWG) with advanced features. Firstly, building upon existing AWG formulations, design equations are provided, libraries developed and all this is experimentally validated with devices in Indium Phosphide (InP) and Silicon-on-insulator (SOI) technologies. Next, a model and experimental validation is reported for an Interleave-Chirped Arrayed Waveguide Grating (IC-AWG), which is able to process optical signals as WDM demultiplexer, polarization splitter and phase diversity component all in a single device. This device was fabricated and tested in InP technology. The second innovative AWG demonstrated in this thesis, a Reflective type (R-AWG), whose layout allows for tailoring the pass-band shape and to change the spectral resolution. A demonstration of design and fabrication for this device is provided in SOI technology. The last AWG with innovative concepts is one driven by Surface Acoustic Waves (AWG-SAW), where the spectral channels can be tuned by means of acousto-optic effect. The device was fabricated in Aluminium Gallium Arsenide (AlGaAs) technology, and measurements are provided to validate the concept and design flow. In parallel this thesis has resulted in the development of different AWG layouts for a wide number of (generic) technologies and foundries, coded into design libraries, of use in a de-facto standard software employed for the design of photonic integrated circuits. These design libraries have been licensed to the UPV spin-off company VLC Photonics S.L.
[ES] La presente tesis se ha centrado en el modelado, diseño y demostración experimental del dispositivo Arrayed Waveguide Grating (AWG) con funcionalidades avanzadas. Primero, usando la formulación existente sobre AWGs se aportan ecuaciones y librerías de diseño, y se validan experimentalmente por medio de dispositivos fabricados en tecnologías de Indium Phosphide (InP) y Silicon-on-insulator (SOI). Después, se reporta un modelo y demostración experimental para un Interleave-Chirped Arrayed Waveguide Grating (IC-AWG), el cual es capaz de procesar señales ópticas como demultiplexor WDM, divisor de polarización y componente de diversidad de fase en un único dispositivo. Este dispositivo fue fabricado y probado en tecnología de InP. El segundo AWG innovador demostrado en esta tesis es de tipo Reflectante (R-AWG), cuyo diseño permite modificar la forma espectral del canal y cambiar su resolución espectral, incluyendo una demostración de diseño y fabricación de este dispositivo en tecnología de SOI. El último AWG que incluye conceptos innovadores es uno sintonizable por Acoustic Waves (AWGSAW), donde los canales espectrales pueden ser sintonizados por medio del efecto acusto-óptico. Dicho dispositivo fue fabricado en tecnología de Aluminium Gallium Arsenide (AlGaAs), y se han incluido medidas experimentales para validar el concepto y el flujo de diseño. En paralelo junto con esta tesis se han desarrollado diferentes diseños para el AWG en un amplio número de tecnologías (genéricas) y plataformas de fabricación, implementadas en unas librerías de diseño para uno de los softwares m¿as utilizados para el diseño de circuitos integrados ópticos, siendo actualmente el estándar de facto. Dichas librerías de diseño han sido licenciadas a la compañía VLC Photonics S.L., spin-off de la UPV.
[CAT] La present tesi ha estat centrada en el modelatge, disseny i demostració experimental del dispositiu Arrayed Waveguide Grating (AWG) amb funcionalitats avançades. Primer, usant la formulació existent sobre AWGs s'aporten equacions i llibreries de disseny, i es validen experimentalment per mitjà de dispositius fabricats en tecnologies de Indium Phosphide (InP) i Silicon-on-insulator (SOI). Després, es reporta un model i demostració experimental per a un Interleave-Chirped Arrayed Waveguide Grating (IC-AWG), el qual és capaç de processar senyals òptiques com demultiplexor WDM, divisor de polarització i component de diversitat de fase en un únic dispositiu. Aquest dispositiu va ser fabricat i provat en tecnologia de InP. El segon AWG innovador demostrat en aquesta tesi és de tipus Reflector (R-AWG), amb un disseny que permet modificar la forma espectral del canal i canviar la seua resolució espectral, incloent una demostració de disseny i fabricació d'aquest dispositiu en tecnologia de SOI. L'últim AWG que inclou conceptes innovadors és un sintonitzable per Acoustic Waves (AWG-SAW), on els canals espectrals poden ser sintonitzats per mitjà de l'efecte acusto-òptic. Aquest dispositiu va ser fabricat en tecnologia de Aluminium Gallium Arsenide (AlGaAs), i s'han inclòs mesures experimentals per validar el concepte i el flux de disseny. En paral.lel juntament amb aquesta tesi s'han desenvolupat diferents dissenys per al AWG en un ampli nombre de tecnologies (genèriques) i plataformes de fabricació, implementades en unes llibreries de disseny per a un dels programaris més utilitzats per al disseny de circuits integrats òptics, sent actualment l'estàndard de facto. Aquestes llibreries de disseny han estat llicenciades a la companyia VLC Photonics S.L., spin-off de la UPV.
Gargallo Jaquotot, BA. (2016). Advanced arrayed waveguide gratings: models, design strategies and experimental demonstration [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/74646
TESIS

This thesis presents a study of the nonlinear limits of coherent, long-haul, optical fibre transmission systems and studies the capabilities of digital and all-optical nonlinearity compensation techniques to enhance their performance. By deriving the theoretical description of optical fibre nonlinear Kerr effects, this thesis presents theoretical, numerical, and experimental evidence showing that the compensation efficiency of deterministic nonlinear impairments in OPC assisted transmission system is highly dependent on the span length. This document shows that the deployment of multiple OPCs, in a system limited by deterministic signal-signal nonlinear interactions, can negate the performance enhancement achieved by a single OPC. I have derived, and verified by simulations, closed form equations that accurately represent the ultimate nonlinear threshold of the nondeterministic nonlinear signal-noise interaction limit in discretely amplified and quasi-lossless Raman optical fibre transmission systems. This nondeterministic nonlinear threshold can be unveiled when deploying ideal nonlinearity compensation techniques and can be minimised by deploying multiple OPCs. In this thesis, I have experimentally shown that the performance enhancement achieved bymid-link OPC when deployed in discretely amplified transmission system is highly dependent on the bandwidth of the signals propagating along the system. The experimental results have shown that the OPC enhances the reach of discretely amplified transmission system by 43%,32%, and 24% for 2x28Gbaud, 4x28Gbaud, and 8x28Gbaud of PM-QPSK signals,respectively. Also, I have experimentally demonstrated the highest reported reach enhancement of 72% (compared to EDC system) for 3.6Tbps (30x30Gbaud PM-QPSK, spectral efficiency of 3.6bps/Hz); when deploying a mid-link OPC in distributed Raman system.

Passive optical networks (PONs) are a promising economic solution in delivering data to the end-user. We demonstrate experimentally the uplink of a spectral-amplitude-coded optical code division multiple access (SAC-OCDMA) and an optical time division multiple access (OTDMA) PON, with burst-mode reception. The receiver performs clock and data recovery (CDR), phase acquisition and forward-error-correction (FEC). Using FEC we demonstrate an error-free 7x622 Mbps uplink of an incoherent SAC-OCDMA PON, while operating at a relatively low power of around -24 dBm. In going to from a back-to-back architecture to a local sources PON configuration the penalty introduced is less than 1 dB. We show that the burst-mode functionality of the receiver enables instantaneous phase acquisition and zero packet loss. However, it introduces a power penalty of around 1dB, which is the price to pay to accommodate bursty traffic and achieve instantaneous phase acquisition using zero bits of preamble.
Les réseaux optiques passifs (PONs - "passive optical networks”) sont une solution économique pour la livraison de données à l'utilisateur final. Nous démontrons expérimentalement l'uplink d'un lien CDMA (accès multiples à répartition des codes) et TDMA (accès multiples à répartition dans le temps) PON, avec réception qui supporte un trafic de paquets en rafale ("burst-mode traffic"). Le récepteur peut rétablir rapidement les impulsions d'horloge et les données (CDR "clock-and-data recovery") et effectuer la correction d'erreurs sans voie de retour (FEC - "forward error correction"). En utilisant un FEC, nous démontrons une transmission 'uplink' sans-erreur à 7x622 Mbps d'un lien SAC-OCDMA incohérent PON, opérant à une puissance relativement basse d'environ -24 dBm. D'une configuration jumelée à une configuration de PON, la pénalité de puissance est de moins de 1 décibel. Nous montrons que le récepteur permet l'acquisition de phase de façon instantanée sans perte de paquets donnant une pénalité de puissance d'environ 1 décibel, le prix à payer pour supporter le trafic de paquets en rafale.

Thesis (BSc. (Hons))--Australian National University, 2002.
Title from title screen (viewed July 31, 2002). Available via the Australian National University Library Electronic Pre and Post Print Repository.

Dissertação (mestrado)—Universidade de Brasília, Decanato de Pesquisa e Pós-Graduação, Instituto de Ciências Biológicas, Instituto de Física, Instituto de Química, Faculdade UnB Planaltina, Programa de Pós-Graduação em Ensino de Ciências, Mestrado Profissional em Ensino de Ciências, 2017.
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O presente trabalho teve por objetivo investigar o emprego de experimentos demonstrativo-investigativos para a aprendizagem de conceitos termoquímicos. A realização de experimentos demonstrativo-investigativos pode facilitar a apropriação de conceitos científicos por parte dos alunos. A seleção dos experimentos, como também a estruturação do roteiro experimental, teve como fundamentação as proposições de Silva, Machado e Tunes (2010), que trazem um novo olhar acerca da experimentação e o seu papel durante a aprendizagem em Ciências. A metodologia pensada para esse trabalho tem aspectos qualitativos e a sua coleta de dados se deu por meio de perguntas abertas para levantamento das concepções prévias dos alunos sobre o conteúdo, e, com a realização de perguntas para avaliação da aprendizagem após a realização de oficinas experimentais. As oficinas foram organizadas em um módulo de ensino orientado para professores, configurando a proposição dessa pesquisa. A partir da utilização dos experimentos demonstrativo-investigativos perceberam-se melhorias no aprendizado de conceitos termoquímicos.
The objective of this work was to investigate the use of demonstrative-investigative experiments for the learning of thermochemical concepts. The realization of demonstrative-investigative experiments can facilitate the appropriation of scientific concepts by the students. The selection of the experiments as well as the structuring of the experimental script was based on the propositions of Silva, Machado and Tunes (2010), which bring a fresh look about experimentation and its role during science learning. The methodology designed for this work has qualitative aspects and its data collection was done through open questions gathering of previous conceptions of students about the content and with the realization of questions to evaluate the learning after the realization of workshops experiments. The workshops were organized in a teacher-oriented module configuring the teaching proposal of this research. From the use of the demonstrative-investigative experiments improvements in the learning of thermochemical concepts were noticed.

La Self-Mixing Interférométrie (SMI) a été étudiée de manière approfondie au cours des cinq dernières décennies dans diverses applications. Les capteurs selon la technique SMI ont la diode laser comme la source de lumière, l'interféromètre et le détecteur. La lumière de la diode laser se propage vers une cible éloignée où elle est partiellement réfléchie ou rétrodiffusée avant d'être réinjectée dans la cavité active du laser. Lorsque la diode laser subit le retour optique externe, la lumière réfléchie imprimée avec des informations provenant de la cible éloignée ou du milieu de cavité externe induit une perturbation des paramètres de fonctionnement du laser. Pour les capteurs de mesure SMI tels que les applications de mouvement harmonique et de distance absolue, la méthode de comptage des franges est essentiellement utilisée pour déterminer respectivement le déplacement et la distance de la cible. La modélisation du phénomène SMI a été développée. L'équation unique qui décrit la condition de phase imposée par la rétro-injection optique est généralement appelée équation de phase. L'un des paramètres les plus importants cet équation est le paramètre C. Quand le C 1, le comportement du laser est stable. En revanche, quand le C > 1, des phénomènes plus complexes sont observés tels que l'effet d'hystérésis, la présence de multiples fréquences d'émission, la séparation de la ligne d'émission de fréquence causer la saut de mode et le phénomène de disparition des franges. Une approche bien acceptée dans la communauté décrit les régimes de SMI en fonction de la valeur du C de sorte que : le régime faible (0.1 < C < 1), le régime modéré (1 < C < 4.6) et le régime fort (C > 4,6). Le paramètre de rétro-injection C est directement impliqué dans le phénomène de disparition des franges. Bernal et al. a décrit que ce phénomène dépend de la régime qui décrits ci-dessus, c'està-dire que les franges commencent à disparaître uniquement dans le régime forte de la rétroinjection d’optique, tandis que Yu et al. a démontré que le nombre des franges est divisée par 2 dans la région 2 (7,8 < C < 14,0), 3 dans la région 3 (14,0 < C < 20,3) et ainsi de suite. Autres publications a proposé que deux paires de franges interférométriques pour une période complète de modulation disparaissent quand il y a une variation de C de 2. Cependant, à notre connaissance, aucune explication ou théorie précise sur le mécanisme de ce phénomène n'a été publiée jusqu'à présent. Dans cette thèse, nous rapportons l'observation de la disparition des franges dans le schéma de mesure de distance absolue. Par rapport au schéma de détection des vibrations, l'approche de la distance absolue garantit un paramètre de rétro-injection C stable permettant ainsi des conditions expérimentales plus répétables. Comme la cible est fixée à une certaine distance, l'amplitude de la lumière rétrodiffusée est facile à contrôler en utilisant des atténuateurs d’optiques variables. Les résultats expérimentaux montrent que le nombre de franges interférométriques continue de diminuer dans le signal SMI lorsque l'amplitude du coefficient de réflexion de la cible augmente
Self-mixing Interferometry has been studied extensively in the last five decades in various sensing applications. Sensors under the SMI technique have the laser diode as the light source, the interferometer, and the detector. The light from the laser diode propagates towards a distant target where it is partially reflected or back-scattered before being re-injected into the active cavity of the laser. When the laser diode experiences the external optical feedback, the reflected light imprinted with information from the distant target or from the external cavity medium induces perturbation to the operating parameters of the laser. For SMI measurement sensors such as harmonic motion and absolute distance applications, the fringe counting method is basically used to determine the target's displacement and distance respectively. Two different approaches to modelling the SMI phenomenon have been developed: the three-mirror cavity and the perturbation of the rate equation. The single equation that describes the phase condition imposed by the optical feedback is usually referred to as the excess phase equation. One of the most important and most useful parameters in the excess phase equation is the feedback parameter C as it can be used to qualitatively categorize the regime of the laser under optical feedback. When the feedback level C < 1, the laser behaviour is stable. On the other hand, when the feedback level C > 1, more complex phenomena are observed such as hysteresis effect, presence of multiple emission frequencies (including the unstable frequencies), apparent splitting of the emission line due to mode hopping and fringe disappearance phenomenon. The fringes disappearance phenomenon in the self-mixing interferometry occurs whenever the external round-trip phase at free-running state is modulated by either external modulation such as external cavity length changes or internal modulation when the laser injection current is modulated with a high back-scattered light power. This phenomenon has been observed by many authors for harmonic motion or vibration application and more recently in the case of the absolute distance measurement scheme when the laser injection current is modulated in the triangle waveform. This phenomenon is highly dependent on the feedback parameter C and it is described in detail based on the coupled cavity model. The primary cause for fringes disappearance is demonstrated to be the expansion of the excess phase equation stable solutions range with the increment of the parameter C, thus reducing the number of stable solutions for a given phase stimulus. This new approach in the modelling of the fringe disappearance phenomenon allows determination of the C values for which a pair of fringes are expected to disappear and as a consequence correlates the number of missing fringes to the value of C. This approach is validated both by a behavioural model of the laser under optical feedback and by a series of measurements in the SMI absolute distance configuration

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
Universidade Federal Fluminense. Instituto de Ciências Exatas. Programa de Pós-Graduação em Ensino de Física. Volta Redonda,RJ.
Este trabalho descreve a elaboração, aplicação e avaliação de uma sequência didática para o ensino dos conceitos de dilatação térmica no ensino médio explorando experimentos demonstrativos. O produto apresentado é composto por um kit formado por quatro experimentos demonstrativos, a saber, acionamento de campainha por dilação de barra metálica, dilatação anel metálico com esfera, lâminas com dois materiais mostrando curvatura da lâmina e modelo de estrutura cristalina, além de um roteiro de atividades. O produto educacional está ancorado na Teoria de Aprendizagem Significativa, de Ausubel e busca interagir com os conhecimentos prévios dos alunos, através de atividades que relacionam os conceitos com consequências cotidianas. O material foi elaborado para ser aplicado em dois tempos de 50 minutos, em acordo com a reduzida carga horária da disciplina de Física nesta modalidade de ensino. O produto foi aplicado em colégio da rede estadual de ensino no Estado do Rio de Janeiro e o resultado da análise mostrou envolvimento dos alunos nas atividades e bom desempenho dos alunos nas mesmas. Acreditamos que o produto seja potencialmente significativo.
This work describes the elaboration, application and evaluation of a didactic sequence to teach linear dilation of materials in high school level. The educational product is composed by four demonstrative experiments namely bar dilation, ring dilation, bi-material strip, and a crystalline structure model. The experiments are followed by a sequence of activities which relies the physical concepts with quotidian situations. Our work is based on the Theory of Meaningful Learning, from David Ausubel. The activities requires interaction between previous knowledge and concrete situations in order to contribute to a meaningful learning. The resulting educational product was applied in a High School institution of the network of Rio de Janeiro State. The application time is two fifty minutes class, performing a hundred minutes, which is appropriate to the physical class in this level of teaching. The results of our analysis of the application show that our product is potential meaningful to teach thermal dilation

Thesis: S.M., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2016.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 49-52).
In this thesis, we implement Bayesian inference and Bayesian experiment design in a model materials science problem. We demonstrate that by observing the behavior of a film deposited on a substrate, certain features of the substrate may be inferred, with quantified uncertainty. We show that Bayesian experimental design can be used to design efficient experiments. The substrate in this model problem is a Gaussian random field, and the film is a phase separating mixture modeled by the Cahn-Hilliard equation. A key feature of the inference and the experiment design is a stochastic reduced-order model.
by Raghav Aggarwal.
S.M.

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The search for the better understanding about the use of experimental activities during the expositive classes and the identification of a appropriate dynamics discourse this teaching practice have been the subject of several researches, discussions and analysis in order to provide the most meaning and attractive Physics teaching. In this research work we investigate, we investigate if the teaching strategy based on the application of experimental demonstration activities in the classroom, in the perspective of the Vygotsky‟s sociocultural theory, makes possible the social interaction of students with teacher and students together, in order to contribute to knowledge construction and reframing of teaching and learning of physics. In this sense, we focus our analysis on the discourses that occur around these activities. Teacher and students of the second year of high school of the State School in the city of Serra Branca‟s city in Paraiba make up the universe of this study, where we use a qualitative methodology, type Case Study, taking as research instrument the free observation in the natural environment of the classroom and a semi-structured interview with the teacher. To facilitate the transcription of the dialogues occurred in the classroom as auxiliary resource, use audio and video recordings.
A busca por uma melhor compreensão a respeito da utilização de atividades experimentais no decorrer das aulas expositivas e a identificação de dinâmicas discursivas adequadas a essa prática pedagógica têm sido motivo de diversas pesquisas, discussões e análises no intuito de proporcionar um ensino de Física mais significativo e atraente. Neste trabalho de pesquisa, objetivamos investigar se a estratégia de ensino baseada na aplicação de atividades experimentais de demonstração em sala de aula, na perspectiva da teoria sociocultural de Vygotsky, torna possível a interação social dos alunos com o professor e dos alunos entre si, de forma a contribuir para a construção do conhecimento e resignificação do processo de ensino e aprendizagem de Física. Neste sentido, focamos nossa análise nos discursos que ocorrem em torno dessas atividades. Professora e alunos do segundo ano do Ensino Médio de uma Escola Estadual da cidade de Serra Branca-PB compõem o universo deste estudo, em que utilizamos uma metodologia de natureza qualitativa, do tipo Estudo de Caso, tendo como instrumento de investigação a observação livre no ambiente natural de sala de aula e uma entrevista semi-estruturada com a professora. Para facilitar a transcrição dos diálogos ocorridos em sala de aula, como recurso auxiliar, utilizamos gravações em áudio e vídeo.

International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, Nevada
This paper is a follow up to a paper presented at ITC 2002 entitled “Wireless Local Area Network for Data Telemetry from Fast Moving Nodes” by R. J. Bamberger, G. R. Barrett, R. A. Nichols, and J. L. Burbank of the Johns Hopkins University Applied Physics Laboratory, and M. H. Lauss of the Yuma Test Center at the U.S. Army Yuma Proving Ground (YPG). In that paper, network-centric data telemetry systems, specifically those based on commercial off- the-shelf (COTS) technologies such as the IEEE 802.11b Wireless Local Area Network (WLAN), were offered as an improvement over traditional frequency modulated (FM) data telemetry systems. The feasibility study of using WLANs for data telemetry considered both the radio frequency (RF) link over extended ranges and the effect due to Doppler shift. This paper describes an experiment designed to test those previous analyses.

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Este trabalho tem a finalidade de propor uma sequência didática, com abordagem histórico-filosófica, utilizando-se de experimentos e demonstrações históricas na introdução de conceitos do eletromagnetismo no Ensino Médio. Através desta sequência didática, apresenta-se aos estudantes do Ensino Médio o conceito de ondas eletromagnéticas, numa dinâmica histórica que inclui discussões a respeito da natureza da ciência. O experimento histórico escolhido didaticamente como central é o experimento demonstrativo de Oliver Lodge, que projetou um sistema efetivo de recepção das ondas eletromagnéticas cuja principal inovação foi o emprego do coesor no lugar da antena de Hertz. Nessa dissertação, assume-se uma perspectiva pedagógica que se aproxima da Pedagogia Histórico-Crítica (PHC) na medida em que considera a difusão dos conteúdos, vivos e atualizados e a transmissão de conhecimentos historicamente acumulados pela humanidade, tarefas centrais da Educação. Constatamos uma afinidade entre a PHC e o ensino de ciências e concluímos que o referencial da PHC pode subsidiar o uso da História e da Filosofia da Ciência no ensino de ciências. Por fim, apresenta-se um relato e avaliação do desenvolvimento e aplicação efetiva da sequência didática proposta em sala de aula. O Produto Educacional desenvolvido neste trabalho de mestrado consiste na sequência didática e sua descrição, dos textos e questionários utilizados nas aulas e do texto de apoio ao professor.
This work has the goal of proposing a didactic sequence, with historical-philosophical approach, using experiments and historical demonstrations in the introduction of electromagnetism concepts in High School. Through this didactic sequence, the students of high school are presented to the concept of electromagnetic waves, in a historical dynamic that includes discussions about the nature of science. The historical experiment chosen didactically as central is the Oliver Lodge's demonstrative experiment, which designed an effective system for receiving electromagnetic waves whose main innovation was the use of the coesor instead of the Hertz’s antenna. In this dissertation, is assumed a pedagogical perspective that approaches the Historical-Critical Pedagogy (PHC) insofar as it considers the dissemination of live and up-to-date contents and the transmission of knowledge historically accumulated by humanity, central tasks of Education. We verified an affinity between the PHC and the Science Teaching and we concluded that the PHC referential can subsidize the use of History and Philosophy of Science in Science Teaching. Finally, a report and evaluation of the development and effective application of the didactic sequence proposed in the classroom is presented. The Educational Product developed in this master's work consists of the didactic sequence and its description, in the texts and questionnaires used in the classes and in the text to support the teacher.

Thesis (Ph. D.) -- University of Maryland, College Park, 2008.
Thesis research directed by: Dept. of Electrical and Computer Engineering Engineering. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.

The ever-increasing demands for transmission capacity are the cause for the quick evolution of optical communication systems. Channel transmission at 100 Gb/s is already being considered by network operators. The major transmission impairments at these high rates are intra-channel and inter-channel nonlinearities, nonlinear phase noise, and polarization mode dispersion. By implementing LDPC-coded modulation schemes with soft decoding and Bahl-Cocke-Jelinek-Raviv (BCJR) algorithm for equalization we have demonstrated significant improvements in system performance experiencing several impairments simultaneously. The new turbo-equalization scheme is used as a mean to simultaneously mitigate both linear and nonlinear impairments. This approach is general and applicable to both direct and coherent detection.We provide comprehensive study of LDPC codes suitable for implementation in high-speed optical transmission systems. We determine channel capacity based on the forward step of the BCJR algorithm and show that by using LDPC codes we can closely approach the maximum transmission capacity that is possible. We propose the multilevel maximum a posteriori probability (MAP) turbo equalization scheme based on multilevel BCJR algorithm and an LDPC decoder, which considers independent symbols transmitted over both polarizations as two dimensional super-symbols. The use of multilevel modulation schemes provide higher spectral efficiency, while all related signal processing is performed at lower symbol rates, where dealing with PMD compensation and fiber nonlinearities mitigation is more manageable. We show significant improvement in system performance over a system employing an equalizer that considers symbols transmitted in different polarizations as independent.

This thesis presents a decentralized electromagnetic formation flying (EMFF) control method using frequency-multiplexed sinusoidal control signals. We demonstrate the EMFF control approach in open-loop and closed-loop control experiments using a single-degree-of-freedom testbed with an electromagnetic actuation system (EAS). The EAS sense the relative position and velocity between satellites and implement a frequency-multiplexed sinusoidal control signal. We use a laser-rangefinder device to capture the relative position and an ARM-based microcontroller to implement the closed-loop control algorithm. We custom-design and build the EAS that implements the formation control in one dimension. The experimental results in this thesis demonstrate the feasibility of the decentralized formation control algorithm between two satellites.

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Este estudo teve o objetivo de investigar a utilização de uma proposta para ensino de conteúdos de Física, visando promover a melhoria da qualidade desse ensino, com foco na combinação de recursos educacionais experimentos demonstrativos, vídeos, e simulações computacionais no início de aulas expositivas para estudantes de uma Escola Militar, a saber, a Escola de Aprendizes-Marinheiros do Espírito Santo (EAMES) localizada na Enseada do Inhoá em Vila Velha-ES. A investigação foi desenvolvida a partir da unidade de ensino Ondas que foi dividida em três subunidades denominadas Movimento Periódico, Movimento Ondulatório e Ondas Sonoras. Nesse contexto, este estudo investigou se a Proposta de Ensino contribuía para a melhoria no desempenho do estudante na disciplina Física; qual recurso educacional proporcionou interesse e atenção aos conteúdos abordados em cada subunidade de ensino; qual recurso educacional mais contribuiu para a visualização dos conceitos por parte dos alunos, bem como qual recurso educacional mais contribuiu para promover a participação deles. Utilizou-se um Delineamento Experimental com o uso de estatística inferencial a fim de avaliar o efeito da proposta de ensino no contexto estudado. Os resultados apontaram que a proposta de ensino investigada não contribuiu para a melhoria do desempenho dos estudantes na Avaliação Escrita Curricular, uma vez que não foram encontradas diferenças estatisticamente significativas entre as médias do Grupo de Controle e do Grupo Experimental. No entanto, constatou-se que os recursos utilizados contribuíram de igual maneira para a promoção do interesse, da atenção, da visualização e da participação dos alunos pertencentes ao Grupo Experimental durante as aulas expositivas de cada subunidade de ensino.

A theoretical method for extracting the rotational degrees of freedom from a reconstructed three-dimensional velocity field has been developed. To extract the angular velocities the curl of the translational velocities must be performed. The three-dimensional velocity field is to be equally spaced so that the DFT-IDFT technique of taking partial derivatives of the translational velocities is used. A program was written in C along with MATLAB® which performed the theoretical calculations. Two proposed methods of experimentally verifying the angular velocity data is developed using a Kistler translational/angular piezobeam accelerometer to compare against the DFT-IDFT partial derivative technique for calculating the angular velocities.
Master of Science

Nanomagnetic logic, incorporating logic bits in the magnetization orientations of single-domain nanomagnets, has garnered attention as an alternative to transistor-based logic due to its non-volatility and unprecedented energy-efficiency. The energy efficiency of this scheme is determined by the method used to flip the magnetization orientations of the nanomagnets in response to one or more inputs and produce the desired output. Unfortunately, the large dissipative losses that occur when nanomagnets are switched with a magnetic field or spin-transfer-torque inhibit the promised energy-efficiency. Another technique offering superior energy efficiency, “straintronics”, involves the application of a voltage to a piezoelectric layer to generate a strain which is transferred to an elastically coupled magnetrostrictive layer, causing magnetization rotation. The functionality of this scheme can be enhanced further by introducing magnetocrystalline anisotropy in the magnetostrictive layer, thereby generating four stable magnetization states (instead of the two stable directions produced by shape anisotropy in ellipsoidal nanomagnets). Numerical simulations were performed to implement a low-power universal logic gate (NOR) using such 4-state magnetostrictive/piezoelectric nanomagnets (Ni/PZT) by clocking the piezoelectric layer with a small electrostatic potential (~0.2 V) to switch the magnetization of the magnetic layer. Unidirectional and reliable logic propagation in this system was also demonstrated theoretically. Besides doubling the logic density (4-state versus 2-state) for logic applications, these four-state nanomagnets can be exploited for higher order applications such as image reconstruction and recognition in the presence of noise, associative memory and neuromorphic computing. Experimental work in strain-based switching has been limited to magnets that are multi-domain or magnets where strain moves domain walls. In this work, we also demonstrate strain-based switching in 2-state single-domain ellipsoidal magnetostrictive nanomagnets of lateral dimensions ~200 nm fabricated on a piezoelectric substrate (PMN-PT) and studied using Magnetic Force Microscopy (MFM). A nanomagnetic Boolean NOT gate and unidirectional bit information propagation through a finite chain of dipole-coupled nanomagnets are also shown through strain-based "clocking". This is the first experimental demonstration of strain-based switching in nanomagnets and clocking of nanomagnetic logic (Boolean NOT gate), as well as logic propagation in an array of nanomagnets.

Thesis (MScEng (Mechanical and Mechatronic Engineering))--University of Stellenbosch, 2011.
ENGLISH ABSTRACT: The world's astronomy community is working together to build the largest and most sensitive radio telescope in the world namely: the SKA (Square Kilometre Array). It will consist of approximately three thousand dishes which will each require accurate positioning. The Square Kilometer Array has a testbed called the Phased Experimental Demonstrator (PED) in Observatory, Cape Town. A hexapod positioning mechanism is required to position a 3.7 m radio telescope which forms part of an array of seven radio telescopes. This thesis details the design process of the hexapod system. The design consists of the mechanical design of the joints and linear actuators, a kinematic and dynamic model, a controller and a user interface. In order to verify the design for the PED hexapod a scaled prototype was designed, built and tested. The hexapod's repeatability as well as ability to track a path was tested using an inclinometer. The tests confirmed the design feasibility of the PED hexapod and also highlight issues that require care when constructing the full scale hexapod, such as the amount of play in the platform joints. The designed full scale hexapod will have an error angle less than 0.13°, a payload capacity of 45 kg, withstand wind speeds of 110 km/h and cost R160 000.
AFRIKAANSE OPSOMMING: Die wêreld se sterrekundige gemeenskap is besig om saam te werk om die grootste en mees sensitiewe radioteleskoop in die wêreld te bou, naamlik: die SKA (Square Kilometre Array). Dit sal uit ongeveer drie duisend skottels bestaan wat elkeen akkurate posisionering benodig. Die SKA het 'n toetssentrum, genaamd die “Phased Experimental Demonstrator” in Observatory, Kaapstad. 'n Sespoot posisionering meganisme word benodig om die 3.7 m radioteleskoop te posisioneer, wat deel vorm van 'n stelsel van sewe radioteleskope. Hierdie tesis beskryf die proses om die sespoot stelsel te ontwerp. Die ontwerp bestaan uit die meganiese komponent van die koppelings en lineêre aktueerders, 'n kinematiese en dinamiese model, 'n beheerder, asook 'n gebruikersintervlak. 'n Geskaleerde prototipe is ontwerp, gebou en getoets om die ontwerp te verifieer. Die platform se herhaalbaarheid sowel as akkuraatheid om 'n pad te volg was getoets met 'n oriëntasie sensor. Die toetse het probleme uitgelig wat versigtig hanteer moet word gedurende die konstruksie van die volskaalse sespoot, veral die hoeveelheid speling in die koppelings. Die volskaalse sespoot ontwerp het 'n hoek fout van minder as 0.13°, 'n ladingsvermoë van 45 kg en kan 'n windspoed van 110 km/h weerstaan en kos R160 000.

L'optimisation de la forme des pales en fonction des phases de vol constitue un levier puissant dans ladémarche d'amélioration des performances des hélicoptères et de minimisation de leurs impactsenvironnementaux. Cette thèse propose l'étude et la caractérisation d'un concept permettant, grâce àl'utilisation d'un actionneur passif, de contrôler le vrillage d'une pale d'hélicoptère, en vol, en fonctionde la vitesse de rotation. L'actionneur retenu pour tordre une pale rigide est une plaque compositestratifiée munie d'un couplage traction/torsion et intégrée au sein de la pale. Les travaux développés ontpermis de démontrer la faisabilité de ce concept à l'échelle d'un prototype de partie courante de pale. Enpremier lieu, et ce afin de concevoir une architecture de profil adaptée à ce type de plaque, un modèleanalytique a été développé pour relier les caractéristiques des plaques composites à leur vrillage soussollicitations statique et dynamique. Une formulation simple de la réponse en vrillage a permisd'optimiser les séquencements de ces plaques dans l'objectif de maximiser le couplage en minimisant lesdéformations résiduelles liées au procédé de fabrication. Les plaques optimisées et fabriquées ontensuite été caractérisées sous traction quasi-statique uniforme puis sur un banc rotatif. Plusieurstechniques expérimentales ont été développées dans le but de quantifier le vrillage. Ce travail a conduità l'insertion d'une plaque épaisse dans un profil de pale. Sous un chargement statique, les tronçons ontexposé un vrillage de l'ordre de 2 °.m-1. Ces multiples expériences et les différentes simulationsréalisées permettent d'envisager des essais en soufflerie sur ces prototypes de pales
Blade morphing optimization during a flight provides a powerful lever to improve helicoptersperformance and reduce their fossil based energy consumption. This PhD thesis examines a newconcept of passive blade twist controlled by the rotation speed. One of the most suitable actuator able totwist a stiff blade is an integrated laminate with extension/twist coupling. Developed work proves thefeasibility of this assembly at a laboratory scale. In a first stage, an analytical model was developed toestimate the twist behaviour of a laminate subjected to static and dynamic loads. This effectivecalculation of the twist response was used to optimize the stacking sequence in order to improve thecoupling and minimize residual stresses due to the manufacturing process. Some optimized plates havebeen manufactured and characterized using uniform tensile test and a rotative bench. Severalmeasurement methods have been developed to quantify twist. This study led to the integration of a thicklaminate in a blade airfoil profile. Under quasi-static axial loading, these blade sections have shownapproximately 2 °.m-1 in twist. Results from experiments and models make it possible to expect windtunnel tests on these adaptive twist blades

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
The present work intends to produce and provide instructional material to high school teachers of physics, focusing on workshop methodology as a viable alternative to physics classes. It is proposed to equip teachers with innovative tools and context for the process of teaching-learning physics, based on the use of Information and Communication Technologies (ICT) and experimental practices. Detailed scripts were developed for the implementation of the methodology and offer of workshops in classrooms about Modern Physics (MP). From the literature it was observed that the workshops when developed with its own teachers, would make it possible to overcome deficits in their initial formation, including those regarding to the use of experimentation, technology, innovative methodologies and concepts of MP. Studies have demonstrated the real need to help teachers in the search for new alternatives for insertion of physics and its teaching in the social and technological reality of its students; As well as the effectiveness of instructional material in overcoming, even if timidly, some shortcomings with regard to pedagogical practice and the teaching of certain challenging content, in a contextualizing and motivating perspective.
O presente trabalho objetivou a produção e disponibilização de material instrucional aos professores do Ensino Médio (EM) de física, focando-se a metodologia de oficinas como alternativa viável às aulas de física. Propõe-se a instrumentalização do professor com ferramentas de inovação e de contextualização para o processo ensino-aprendizagem de física, baseada no uso das Tecnologias da Informação e Comunicação (TIC) e das práticas experimentais. Como produto foram elaborados roteiros detalhados para a implementação da metodologia e oferta das oficinas em salas de aulas sobre tópicos de Física Moderna (FM). A partir da literatura de referência observou-se que as oficinas, quando trabalhadas com os próprios professores, possibilitariam a superação de déficits na formação inicial, inclusive no que diz respeito ao uso da experimentação, da tecnologia, de metodologias inovadoras e, de conceitos em FM. Estudos tem demonstrado a necessidade real de se auxiliar os professores na busca por novas alternativas para inserção da física e do seu ensino na realidade social e tecnológica de seus alunos; assim como, a efetividade do material instrucional em suprir, mesmo que timidamente, algumas lacunas com relação à prática pedagógica e ao ensino de determinados conteúdos desafiadores, numa perspectiva contextualizadora e motivadora.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
Universidade Federal Fluminense. Instituto de Ciências Exatas. Programa de Pós-Graduação em Ensino de Física. Volta Redonda, RJ
O ensino de ciências e Física para os jovens internados no regime socioeducativo sofre limitações que vão desde necessidade de trabalhar em módulos, até impossibilidade de utilização de recursos e métodos usuais no ensino regular. Em particular o agrupamento de disciplinas em módulos faz com que a disciplina de Ciências e, consequentemente conteúdos de Física, não seja vista nos dois últimos módulos do Ensino Fundamental, deixando o aluno distante desses conteúdos quando ele entra no Ensino Médio. Visando complementar o ensino modular nos módulos correspondentes aos anos finais do Ensino Fundamental, foi construído como produto deste trabalho uma sequência de práticas de Física visando iniciar esse público nos conceitos e reflexões trazidos da Física. Na construção da sequência foram consideradas as limitações particulares a que este público está sujeito, a necessidade de prepará-los para a Física no Ensino Médio, bem como a inserção dos temas abordados no contexto de suas experiências cotidianas. Foram selecionadas práticas com materiais de fácil acesso sobre eletrostática, pressão, tensão superficial e calor, para as quais foram criadas um guia de estudos e um questionário de acompanhamento. O objetivo da sequência de práticas foi aguçar a curiosidade e despertar o interesse pelo estudo e pela Física num público com sérias deficiências e lacunas formativas. A ênfase na atividade experimental, além de associar a ciência Física com o seu lado de prático, possibilita que o jovem expresse suas habilidades construtivas e manuais, contribuindo para sua reaproximação com o estudo, tão importante para sua recuperação para a sociedade. Por meio do produto educacional aqui proposto, espera-se contribuir para a construção dos primeiros conceitos físicos da estrutura cognitiva desses jovens. Da mesma forma pretende-se fornecer aos professores que atuam no regime socioeducativo um recursos educacional para realizar sua prática docente de forma mais atraente, interessante e diversificada.
The teaching of science and physics to young people in the socio-educational system suffers limitations ranging from the need to work in modules, to the inability to use resources and usual methods comonn in the formal education. In particular need to group disciplines in modules makes the subjects of Science and Physics not be seen in the last two modules of the midle school level, leaving the student far away from such contents when he enters high school. To complement the modular teaching corresponding to the modules of the final years of midle school, it was built a sequence Physics practices to presente to this public their first concepts and reflections on physics subjects. In the construction of the sequence were considered the particular constraints that the public is subjected, as the need to prepare them for physics in high school, as well as the inclusion of issues usually addressed in the context of their everyday experiences. Simple experiments with easy findind material on electrostatics, pressure, surface tension and heat were selectec, for wich a guide to the practices and revision questionaries were prepared. The purpose of the following practices was to stimulate their curiosity and arouse interest both to the study and to Physics in public with serious contents deficiencies and training gaps. The emphasis on xperimental activity, in addition to associate the physical science with its practical side, allows the youngsters to express their manual skills, contributing to its rapprochement with study, a crucial step towards his recovery to society. Through the educational product here proposed we expect to contribute to the construction of the first physical concepts in cognitive structure of these youngsters. The same way we intend to provide teachers who work in the socio-educational system with an educational resource that enable them to carry out their teaching practice in a more attractive, interesting and diverse way.

Досадашања истраживања указују на позитиван допринос примене ЛЕМ, односно сваке врсте експеримената (ученичких – УЕ и демонстрационих - ДЕ) знању ученика разредне наставе из интегрисаних природних наука. УЕ подразумевају примену имплицитне инструкције, док демонстрациони експерименти подразумевају примену експлицитне инструкције при њиховом извођењу. Међутим, није довољно истражено када при обрађивању одговарајућег садржаја интегрисаних природних наука, у одређеној старосној доби ученика, треба дати приоритет одређеној врсти екперимената, односно којој врсти инструкција за њихову реализацију. Ово је нарочито значајно када се одређени садржаји, које су ученици учили у претходним разредима (вертикално повезани) усложњавају по квалитету, квантитету и обиму. Једни од таквих садржаја су и садржаји о кретању и особинама материјала у трећем разреду.Основни циљ истраживања у овој докторској дисертацији јесте да се испита: допринос примене ЛЕМ, односно УЕ и ДЕ квалитету и трајности знања ученика трећег разреда о кретању и особинама материјала у односу на традиционалну методу (ТМ), као и разлика у доприносу између примене УЕ и ДЕ на истој варијабли (когнитивни домен); мишљење ученика о доприносу примене ЛЕМ (УЕ и ДЕ) стицању тих знања (афективни домен) као и; корелација између квалитета и трајности знања ученика о одабраним садржајима са њиховим мишљењем о доприносу примене ЛЕМ (УЕ и ДЕ) стицању тих знања (когнитивно-афективни домен). У истраживању је учествовао N = 141 ученик трећег разреда из три основне школе са територије Општине Темерин, који су били подељени у три групе: Е1 (која је одабране садржаје учила уз примену УЕ – имплицитна инструкција), Е2 (која је одабране садржаје учила уз примену ДЕ – експлицитна инструкција) и К (која је исте садржаје учила уз примену ТМ – експлицитна инструкција). Методе итраживања су: метода теоријске анализе, експериментална метода, дескриптивна метода и статистичка метода. Примењене технике су тестирање и анкетирање. Тестирање знања ученика о кретању и особинама материјала спроведено је помоћу теста (пре-теста, пост-теста и ре- теста). Анкетирње је реализовано помоћу анкете (пре-анкете и пост-анкете). Питања у обе анкете су креирана према петостепеној скали Ликертовог типа. Пре-анкетом испитано је мишљење ученика Е1 и Е2 групе пре реализације садржаја о кретању и особинама материјала, како би се стекао увид у њихово мишљење о значају примене ЛЕМ у стицању њихових знања у претходним разредима. Пост-анкетом је испитано мишљење ученика Е1 и Е2 групе после реализације ових садржаја, како би се утврдило да ли је дошло до промене у њиховом мишљењу о значају примене ЛЕМ у стицању њихових знања. Резултати пост- анкете су коришћени и за анализу корелације између знања ученика Е1 и Е2 групе на пост-тесту и ре-тесту са њиховим мишљења о доприносу примене ЛЕМ.ЛЕМ више (у већој мери УЕ, него ДЕ) у односу на ТМ доприноси укупном квалитету и трајности знања ученика о кретању и особинама материјала. Ученици Е1 групе остварили су квалитетнија знања (на нивоу евалуације) у односу на ученике Е2 групе, као и квалитетнија знања (на нивоу анализе, евалуације и синтезе) у односу на ученике К групе. Ученици Е2 групе остварили су квалитетнија знања (на нивоу примене евалуације и синетезе) у односу на ученике К групе. Трајност знања ученика Е1 групе о приближна је трајности знања ученика Е2 групе на свим когнитивним нивоима. Међутим, ученици Е1 групе показали су знатно боље задржавање наученог о одабраним садржајима у односу на ученике К групе на нивоу разумевања, примене и евалуације. Ученици Е2 групе остварили су приближна знања ученицима К групе по трајности на свим когнитивним нивоима.Када се упореде резултати пре-анкете и пост-анкете закључује се да су после реализације садржаја о кретању и особинама материјала помоћу ЛЕМ ученици обе групе показали позитивније мишљење (на пост- анкети) о доприносу примене ЛЕМ стицању њихових знања. Поред наведеног уочено је и то да су ученици Е1 групе показали и знатно позитивније мишљење од ученика Е2 групе о доприносу примене ЛЕМ разумевању одабраних садржаја, њиховој заинтересованости на часовима и развоју социјалне интеракције.Постоји позитивна корелација између квалитета (на нивоу знања, разумевања, примене, анализе и евалуације) и трајности знања (на нивоу знања, разумевања и примене) ученика Е1 групе о одабраним садржајима и њиховог мишљења о доприносу примене ЛЕМ стицању тих знања. Позитивна корелација уочена је и између квалитета (на свим нивоима) и трајности знања (на нивоу знања, разумевања, примене, анализе и евалуације) ученика Е2 групе о одабраним садржајима и њиховог мишљења о доприносу примене ЛЕМ тим знањима. Јача корелација између испитиваних варијабли код ученика Е2 групе у односу на ученике Е1 групе само је производ тога колико су остварене вредности у оквиру сваке варијабле приближне. С обзиром на то да су ученици Е2 групе остварили слабији успех у односу на ученике Е1 групе у оквиру свих испитиваних варијабли (квалитет и трајност знања о одабраним садржајима и мишљење ученика о доприносу примене ЛЕМ тим знањима), важно је нагласити да су остварене вредности (резултати) између њиховог знања и мишљења приближније (што је проузроковало и јачу корелацију), него код ученика Е1 групе (што је проузроковало нешто слабију корелацију).Сугерише се да би садржаје о кретању и особинама материјала у трећем разреду требало реализовати уз примену једноставних експеримената (УЕ и ДЕ), при чему би предност требало дати УЕ, који се реализују уз примену имплицитне инструкције. Већом применом УЕ, у односу на ДЕ; утицало би се не само на квалитет и трајност знања ученика разредне наставе о природи, природним процесима и појавама, него и на њихово позитивно мишљење (ставове) о значају примене ЛЕМ у стицању тих знања, али и на сам развој експерименталних вештина и навика, које су ученицима касније неопходне за што самосталнију примену комплекснијих лабораторијских експеримената (у настави диференцираних природних наука).
Dosadašanja istraživanja ukazuju na pozitivan doprinos primene LEM, odnosno svake vrste eksperimenata (učeničkih – UE i demonstracionih - DE) znanju učenika razredne nastave iz integrisanih prirodnih nauka. UE podrazumevaju primenu implicitne instrukcije, dok demonstracioni eksperimenti podrazumevaju primenu eksplicitne instrukcije pri njihovom izvođenju. Međutim, nije dovoljno istraženo kada pri obrađivanju odgovarajućeg sadržaja integrisanih prirodnih nauka, u određenoj starosnoj dobi učenika, treba dati prioritet određenoj vrsti ekperimenata, odnosno kojoj vrsti instrukcija za njihovu realizaciju. Ovo je naročito značajno kada se određeni sadržaji, koje su učenici učili u prethodnim razredima (vertikalno povezani) usložnjavaju po kvalitetu, kvantitetu i obimu. Jedni od takvih sadržaja su i sadržaji o kretanju i osobinama materijala u trećem razredu.Osnovni cilj istraživanja u ovoj doktorskoj disertaciji jeste da se ispita: doprinos primene LEM, odnosno UE i DE kvalitetu i trajnosti znanja učenika trećeg razreda o kretanju i osobinama materijala u odnosu na tradicionalnu metodu (TM), kao i razlika u doprinosu između primene UE i DE na istoj varijabli (kognitivni domen); mišljenje učenika o doprinosu primene LEM (UE i DE) sticanju tih znanja (afektivni domen) kao i; korelacija između kvaliteta i trajnosti znanja učenika o odabranim sadržajima sa njihovim mišljenjem o doprinosu primene LEM (UE i DE) sticanju tih znanja (kognitivno-afektivni domen). U istraživanju je učestvovao N = 141 učenik trećeg razreda iz tri osnovne škole sa teritorije Opštine Temerin, koji su bili podeljeni u tri grupe: E1 (koja je odabrane sadržaje učila uz primenu UE – implicitna instrukcija), E2 (koja je odabrane sadržaje učila uz primenu DE – eksplicitna instrukcija) i K (koja je iste sadržaje učila uz primenu TM – eksplicitna instrukcija). Metode itraživanja su: metoda teorijske analize, eksperimentalna metoda, deskriptivna metoda i statistička metoda. Primenjene tehnike su testiranje i anketiranje. Testiranje znanja učenika o kretanju i osobinama materijala sprovedeno je pomoću testa (pre-testa, post-testa i re- testa). Anketirnje je realizovano pomoću ankete (pre-ankete i post-ankete). Pitanja u obe ankete su kreirana prema petostepenoj skali Likertovog tipa. Pre-anketom ispitano je mišljenje učenika E1 i E2 grupe pre realizacije sadržaja o kretanju i osobinama materijala, kako bi se stekao uvid u njihovo mišljenje o značaju primene LEM u sticanju njihovih znanja u prethodnim razredima. Post-anketom je ispitano mišljenje učenika E1 i E2 grupe posle realizacije ovih sadržaja, kako bi se utvrdilo da li je došlo do promene u njihovom mišljenju o značaju primene LEM u sticanju njihovih znanja. Rezultati post- ankete su korišćeni i za analizu korelacije između znanja učenika E1 i E2 grupe na post-testu i re-testu sa njihovim mišljenja o doprinosu primene LEM.LEM više (u većoj meri UE, nego DE) u odnosu na TM doprinosi ukupnom kvalitetu i trajnosti znanja učenika o kretanju i osobinama materijala. Učenici E1 grupe ostvarili su kvalitetnija znanja (na nivou evaluacije) u odnosu na učenike E2 grupe, kao i kvalitetnija znanja (na nivou analize, evaluacije i sinteze) u odnosu na učenike K grupe. Učenici E2 grupe ostvarili su kvalitetnija znanja (na nivou primene evaluacije i sineteze) u odnosu na učenike K grupe. Trajnost znanja učenika E1 grupe o približna je trajnosti znanja učenika E2 grupe na svim kognitivnim nivoima. Međutim, učenici E1 grupe pokazali su znatno bolje zadržavanje naučenog o odabranim sadržajima u odnosu na učenike K grupe na nivou razumevanja, primene i evaluacije. Učenici E2 grupe ostvarili su približna znanja učenicima K grupe po trajnosti na svim kognitivnim nivoima.Kada se uporede rezultati pre-ankete i post-ankete zaključuje se da su posle realizacije sadržaja o kretanju i osobinama materijala pomoću LEM učenici obe grupe pokazali pozitivnije mišljenje (na post- anketi) o doprinosu primene LEM sticanju njihovih znanja. Pored navedenog uočeno je i to da su učenici E1 grupe pokazali i znatno pozitivnije mišljenje od učenika E2 grupe o doprinosu primene LEM razumevanju odabranih sadržaja, njihovoj zainteresovanosti na časovima i razvoju socijalne interakcije.Postoji pozitivna korelacija između kvaliteta (na nivou znanja, razumevanja, primene, analize i evaluacije) i trajnosti znanja (na nivou znanja, razumevanja i primene) učenika E1 grupe o odabranim sadržajima i njihovog mišljenja o doprinosu primene LEM sticanju tih znanja. Pozitivna korelacija uočena je i između kvaliteta (na svim nivoima) i trajnosti znanja (na nivou znanja, razumevanja, primene, analize i evaluacije) učenika E2 grupe o odabranim sadržajima i njihovog mišljenja o doprinosu primene LEM tim znanjima. Jača korelacija između ispitivanih varijabli kod učenika E2 grupe u odnosu na učenike E1 grupe samo je proizvod toga koliko su ostvarene vrednosti u okviru svake varijable približne. S obzirom na to da su učenici E2 grupe ostvarili slabiji uspeh u odnosu na učenike E1 grupe u okviru svih ispitivanih varijabli (kvalitet i trajnost znanja o odabranim sadržajima i mišljenje učenika o doprinosu primene LEM tim znanjima), važno je naglasiti da su ostvarene vrednosti (rezultati) između njihovog znanja i mišljenja približnije (što je prouzrokovalo i jaču korelaciju), nego kod učenika E1 grupe (što je prouzrokovalo nešto slabiju korelaciju).Sugeriše se da bi sadržaje o kretanju i osobinama materijala u trećem razredu trebalo realizovati uz primenu jednostavnih eksperimenata (UE i DE), pri čemu bi prednost trebalo dati UE, koji se realizuju uz primenu implicitne instrukcije. Većom primenom UE, u odnosu na DE; uticalo bi se ne samo na kvalitet i trajnost znanja učenika razredne nastave o prirodi, prirodnim procesima i pojavama, nego i na njihovo pozitivno mišljenje (stavove) o značaju primene LEM u sticanju tih znanja, ali i na sam razvoj eksperimentalnih veština i navika, koje su učenicima kasnije neophodne za što samostalniju primenu kompleksnijih laboratorijskih eksperimenata (u nastavi diferenciranih prirodnih nauka).
Recent studies indicate that there is a positive contribution of the application of LEM, i.e. of every kind of experiments (student - UE and demonstration - DE) to the knowledge of students of classroom teaching in integrated natural sciences. UEs imply implicit instruction, while demonstration experiments imply explicit instruction in their application. However, it has not been sufficiently investigated when, in addressing the appropriate content of integrated natural sciences, at a given age of the student, priority should be given to a particular type of experiment or to what type of instruction for their realization. This is especially important when certain content which students have learned in previous classes (vertically connected) is complicated on the basis of its quality, quantity and scope. One of these is content about the movement and properties of materials in third grade. The main aim of the research in this doctoral dissertation is to examine the contribution of LEM application i.e. the UE and DE quality and durability of knowledge of third grade students about the movement and properties of materials in relation to the traditional method (TM). Furthermore, it will also look into the difference in contribution between UE and DE application on the same variable (cognitive domain) and students' opinion on the contribution of the application of LEM (UE and DE) to the acquisition of this knowledge (affective domain), as well as the correlation between quality and durability of students' knowledge of selected content with their opinion on the contribution of LEM (UE and DE) application to the acquisition of that knowledge (cognitive-affective domain). This research included N = 141 third grade students from three elementary schools from the territory of Temerin Municipality which were divided into three groups: E1 (which learned selected content using UE - implicit instruction), E2 (which learned selected content using DE - explicit instruction) and K (which learned the same content using TM - explicit instruction). The research methods are as follows: theoretical analysis method, experimental method, descriptive method and statistical method. The used techniques are testing and interviewing. Testing of students' knowledge of movement and material properties was conducted using a test (pre-test, post-test and re-test). Surveys were implemented through a questionnaire (presurvey and post-survey). The questions in both surveys were designed according to a five-point Likert-type scale. Pre-survey examined the opinion of E1 and E2 group students before the realization of the content on movement and material properties, in order to gain insight into their opinion on the importance of applying LEM in acquiring their knowledge in the previous grades. The post-survey examined the opinion of E1 and E2 students after the realization of these contents, in order to determine whether there was a change in their opinion about the importance of applying LEM in acquiring their knowledge. Post-survey results were also used to analyze the correlation between E1 and E2 group students' knowledge on post-test and re-test with their opinions on the contribution of LEM implementation. Compared to TM, LEM contributes more (more UE than DE) to the overall quality and durability of students' knowledge of movement and material properties. E1 group students achieved higher quality (at the level of evaluation) compared to E2 group students, as well as better knowledge (at the level of analysis, evaluation and synthesis) than the K group students. The students of the E2 group achieved higher quality knowledge (at the level of application of evaluation and synthesis) than the students of the K group. The durability of knowledge of E1 group students is approximate to that of E2 students at all cognitive levels. However, the E1 group students showed significantly better retention of the selected content compared to the K group students at the level of understanding, application and evaluation. The E2 group students gained an up-to-date knowledge of the K group students in durability at all cognitive levels. When comparing the results of the pre-survey and the post-survey, it is concluded that after the realization of the content about the movement and the material properties with the LEM, students from both groups showed a more positive opinion (at the post-survey) about the contribution of the application of the LEM to the acquisition of their knowledge. In addition, it was noted that E1 group students showed significantly more positive opinions than E2 group students about the contribution of LEM application to understanding of selected content, their interest in classes and the development of social interaction. There is a positive correlation between the quality (at the level of knowledge, understanding, application, analysis and evaluation) and the durability of knowledge (at the level of knowledge, understanding and application) of E1 group students on selected content and their opinion on the contribution of LEM application to the acquisition of that knowledge. Furthermore, a positive correlation was noticed between the quality (at all levels) and the permanence of knowledge (at the level of knowledge, understanding, application, analysis and evaluation) of E2 group students on selected content and their opinion on the contribution of LEM application to this knowledge. The stronger correlation between the examined variables in the E2 group students compared to the E1 group students is only a product of how the values are close to each variable. Considering that the students of the E2 group achieved less success than the students of the E1 group within all the examined variables (quality and durability of knowledge about the selected contents and students' opinion on the contribution of applying LEM to this knowledge), it is important to emphasize that the achieved values (results) between their knowledge and opinion are closer (which also caused a stronger correlation) than for E1 group students (which caused a slightly weaker correlation). It is suggested that the contents about the movement and properties of the materials in the third class should be realized using simple experiments (UE and DE), with preference given to UEs, which are realized using implicit instruction. Greater use of UEs than DEs; would affect not only the quality and durability of students' knowledge of the classroom teaching about nature, natural processes and phenomena, but also their positive opinion (attitudes) about the importance of applying LEM in acquiring this knowledge, but also to the development of experimental skills and habits itself, which are later necessary for students to apply complex laboratory experiments as independently as possible (in teaching differentiated natural sciences).

A compact air separator demonstrator based on centrifugally enhanced distillation has been studied. The full size device is meant to be used on board of a Two Stage To Orbit vehicle launcher. The air separation system must be able to extract oxygen in highly concentrated liquid form (LEA, Liquid Enriched Air) from atmospheric air. The LEA is stored before being used in a subsequent rocket propulsion phase by the second stage of the launcher. Two reference vehicles are defined, one with a subsonic first stage and one with a supersonic first stage. In both cases, oxygen collection is performed during a cruise phase (M 0.7 and M 2.5 respectively). The aim of the project is to demonstrate the feasibility of the air separation system, investigate the separation cycle design, and assess that the separator design selected is suitable for the reference vehicles.

The project is described from original base ideas to design, construction, extended testing and analysis of experimental results. Preliminary computations for a realistic layout have been performed and the motivations for the choices made during the process are explained. Test rig design, separator design and technical discussion are provided for a subscale pilot unit. Mass transport parameters and flooding limits have been estimated and experimentally measured. Performance has been assessed and shown to be sufficient for the reference Two Stage To Orbit vehicles. The technology developed is found suitable without further optimization, although some volume and mass reduction would be desirable for the supersonic first stage concept. There are many ways of optimisation that can be further investigated. The aim of this program, however, is not to fully optimize the device, but to demonstrate that a device based on a simple, robust, low-risk design is already suitable for the launch vehicles. On top of that analysis, directions for improvements are suggested and their potentials estimated. A complete assessment of those improvements requires further maturation of the technological concept through further testing and practical implementations.

Directions for future work, general conclusions and a vehicle development roadmap have also been provided.

Doctorat en Sciences de l'ingénieur
info:eu-repo/semantics/nonPublished