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The cornet à pistons in French and French-influenced orchestration from 1830 to 1936 /Davis, Joyce Francine January 1990 (has links)
No description available.
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Design Considerations for a Launch Vehicle Development Flight Instrumentation SystemJohnson, Martin L., Crawford, Kevin 10 1900 (has links)
ITC/USA 2011 Conference Proceedings / The Forty-Seventh Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2011 / Bally's Las Vegas, Las Vegas, Nevada / When embarking into the design of a new launch vehicle, engineering models of expected vehicle performance are always generated. While many models are well established and understood, some models contain design features that are only marginally known. Unfortunately, these analytical models produce uncertainties in design margins. The best way to answer these analytical issues is with vehicle level testing. The National Aeronautics and Space Administration respond to these uncertainties by using a vehicle level system called the Development Flight Instrumentation, or DFI. This DFI system can be simple to implement, with only a few measurements, or it may be a sophisticated system with hundreds of measurement and video, without a recording capability. From experience with DFI systems, DFI never goes away. The system is renamed and allowed to continue, in most cases. Proper system design can aid the transition to future data requirements. This paper will discuss design features that need to be considered when developing a DFI system for a launch vehicle. It will briefly review the data acquisition units, sensors, multiplexers and recorders, telemetry components and harnessing. It will present a reasonable set of requirements which should be implemented in the beginning of the program in order to start the design. It will discuss a simplistic DFI architecture that could be the basis for the next NASA launch vehicle. This will be followed by a discussion of the "experiences gained" from a past DFI system implementation, such as the very successful Ares I-X test flight. Application of these design considerations may not work for every situation, but they may direct a path toward success or at least make one pause and ask the right questions.
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Polymer microring resonators for optofluidic evanescent field sensors / Microrésonateurs en anneaux polymères pours capteurs optofluidiques à champ évanescentDelezoide, Camille 18 December 2012 (has links)
La détection optofluidique à champ évanescent, tout particulièrement la biodétection sans marqueur par microrésonateurs optiques, est une technologie émergente faisant l’objet d’une recherche intensive. Dans ce contexte, nous montrons que les microanneaux polymères sont d’excellents transducteurs. Ceci est dû en partie à la facilité et au faible coût de leur fabrication et de leur intégration, mais aussi à leur robustesse. Une méthode rapide, répétable et peu coûteuse a été mise au point pour fabriquer de tels composants, avec de longues durées de vie et des performances représentant l’état de l’art actuel. Un deuxième avantage est l’extrême sensibilité moléculaire en surface. La preuve en est l’obtention d’un signal détectable avec seulement 500 molécules de 5-TAMRA-cadavérine (5-TC, M = 515 g/mol) adsorbées, et ce après un simple traitement UV/ozone. Cependant, les performances des anneaux polymères ne deviennent apparentes qu’une fois le composant couplé à une instrumentation de haute précision. A cet effet, un instrument de mesure fut construit pour mesurer en temps-réel de très faibles variations des résonances optiques en régime optofluidique. Ceci a permit l’observation d’une cinétique d’absorption/désorption de 5-TC sur son antigène. Néanmoins, une réelle détection spécifique ne peut être atteinte qu’avec un instrument multiplexé en transducteurs. Une telle configuration est possible, mais n’a pas encore été développée. Par contre, l’instrument de mesure réalisé peut être utilisé tel quel pour des applications très diverses, de la mesure de coefficients de diffusion à l’étude d’effets thermiques locaux. / Optofluidic evanescent field sensing, especially microresonator-based label-free biochemical sensing, is an emerging technology under intensive study. In this context, we demonstrate that polymeric microring resonators are excellent transducers. It is partly due to the simplicity and cost-efficiency of their fabrication and integration, and also to their robustness: a fast, repeatable and low-cost method was developed to fabricate devices with long lifetimes and state-of-the-art performances. A second advantage is the extreme sensitivity achievable to grafted molecules: a detectable signal was obtained with only a few hundreds of 5-TAMRA-cadaverine (5-TC) molecules, relatively small as compared to nucleic acids, antibodies and other biomolecules. The surface immobilization of 5-TC molecules was achieved after a simple and reproducible UV/ozone procedure for surface preparation. However, the qualities of polymer microring resonators only become apparent when coupled to high-precision instrumentation. In that respect, a measuring instrument was built to detect minute and real-time variations of the optical resonances, and thus in an optofluidic regime. The detection of absorption and desorption of 5-TC molecules on a surface functionalized with its antibody was achieved. However, truly specific responses of the instrument would only be achieved in a multiplexed configuration. Such configuration is achievable, but has yet to be developed. Meanwhile, the measuring instrument, as is, can be used for a wide variety of applications, from the measurement of dispersion coefficients to the study of local thermal effects.
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Turbulence quantique versus classique / Classic vs. Quantum TurbulenceSalort, Julien 16 November 2011 (has links)
Cette thèse s'intéresse à la turbulence dans l'hélium (4He) superfluide, à des températures comprises entre 1.15 K et la température de transition superfluide, Tlambda = 2.17 K, ce qui correspond à une fraction de superfluide rho_s/rho comprise entre 97.6% et 0%. Il s'agit d'un travail essentiellement expérimental dont le but est de comparer la turbulence classique et la turbulence quantique, à l'aide de mesures locales de fluctuations de vitesse et de vorticité. Ces mesures sont complétées par l'analyse de champs de vitesse issus de simulations numériques.Nous avons développé une instrumentation spécifique, adaptée aux écoulements cryogéniques: des tubes de Pitot miniatures, dont les dimensions effectives ont pu être rendues sub-millimétriques, et un capteur original, basé sur la déflection d'une micro-poutrelle (300 microns x 100 microns x 1 microns) mesurée à l'aide d'un micro-résonateur supraconducteur dans la gamme de fréquence du GHz. Un premier prototype de ce capteur, micro-fabriqué à partir d'une galette de silicium, a été réalisé en salle blanche puis validé dans une conduite cryogénique. La résolution spatiale obtenue est du même ordre que celle des meilleurs anémomètres en He II, et il devrait être possible de l'améliorer d'une décade.Les tubes de Pitot ont été placés dans les souffleries superfluides TSF et TOUPIE. La première, fruit d'une collaboration nationale, a fourni un écoulement stationnaire de grille (Rlambda= 250, 1.65 K < T < 2.6 K, rho_s/rho < 80%) et un sillage proche. La seconde soufflerie, refroidie pour la première fois dans le cadre de cette thèse, a fourni un écoulement de sillage lointain (Rlambda = 1100, 1.55 K < T < 4.2 K, rho_s/rho < 86%).Les mesures ont mis en évidence dans ces écoulements des similarités fortes avec les écoulements classiques, aux échelles inertielles: spectre de vitesse en k^{-5/3}, constante de Kolmogorov et taux de turbulence identiques aux écoulements classiques, loi des 4/5, exposants anormaux pour les fonctions de structures des incréments de vitesse (intermittence). À plus petite échelle, les simulations numériques (1.15 K < T < 2.1565 K) mettent en évidence un comportement exotique : l'énergie s'accumule et tend vers l'équipartition, ce qui se traduit par un spectre de vitesse simulé en k^2. Ce phénomène s'accentue à basse température. Enfin, des mesures locales de fluctuation de vorticité ont été réalisées à l'aide de pinces à second son sur une gamme de température comprise entre 1.69 K (rho_s/rho=77%) et 2.01 K (rho_s/rho = 42%). Nous avons observé un raidissement de la pente des spectres de vorticité lorsque la température diminue. Ce résultat peut être interprété comme une conséquence du phénomène d'équipartition mis en évidence dans les simulations numériques à petite échelle. / The focus of this thesis is the turbulence of superfluid 4He at temperatures between 1.15K and the superfluid transition temperature Tlambda = 2.17K, corresponding to a superfluid fraction rho_s/rho between 97.6% and 0%. This work is mostly experimental. We aim to compare classical and quantum turbulence, using local velocity and vorticity fluctuations measurements. These measurements are backed up by numerical simulations.We developed dedicated probes, designed for cryogenic flows: Pitot tubes with sub-millimeter effective size and a new cantilever-based probe (300 microns x 100 microns x 1 microns) whose deflection is measured with a superconducting micro-resonator in the GHz frequency range. A first prototype was micro-machined from a silicon wafer in cleanroom and validated in a superfluid wind tunnel. The resolution was found similar to the one of the best anemometers operating in He~II and will be further improved.The Pitot tubes have been inserted inside two superfluid wind tunnels, TSF and TOUPIE. The former, designed and operated within a national collaboration, provided a stationary grid flow (Rlambda = 250, 1.65 K < T < 2.6 K, rho_s/rho < 80%) and a near-wake flow. The latter (Rlambda = 1100, 1.55 K < T < 4.2 K, rho_s/rho < 86%), which was cooled down for the first time during this thesis, provided a far-wake flow.The measurements have highlighted strong similarities with classical flows at inertial scales: k^{-5/3} velocity spectra, Kolmogorov constant and turbulence intensity indistinguishable above and below the superfluid transition, 4/5-law, anomalous velocity structure functions exponents (intermittency). At smaller scales, the numerical simulations (1.15 K < T < 2.1565 K) exhibit exotic behavior: kinetic energy piles up and tends to equipartition, which makes the simulated velocity spectrum scale like k^2. This phenomenon is enhanced at low temperature. Finally, local vorticity fluctuations measurements have been achieved using second sound tweezers over a temperature range, between 1.69 K (rhos/rho=77%) and 2.01 K (rhos/rho = 42%). We observed that the spectrum scaling steepens as the temperature decreases. This can be interpreted as a consequence of the equipartitioned reservoir evidenced by numerical simulations at small scale.
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Network Analyzer Functionality SimulatorRodriguez, Ramón January 2007 (has links)
<p>The objective of this thesis work was to implement all the hardware and software necessary to simulate the functionality of a Vector Network Analyzer (VNA). With equipment that is already available, and is common in a measurement station, the most common functions of a VNA were implemented, using an Vector Signal Generator, that provide the signal for testing, and a Vector Signal Analyzer, to make all the amplitude and phase measurements. With these instruments and the appropriate software that control them, the basic functionality of a Vector Network Analyzer can be achieved with a reasonable accuracy. With this system, we can reduce costs, avoiding the need of a real VNA and take advantage off instruments that are already available in a laboratory. A Complete measurement system of all four scattering parameters is proposed at the end of the report for future implementation. With this implementation all the different S-parameter measurements were made with an acceptable accuracy that can be comparable to a commercial VNA.</p>
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Network Analyzer Functionality SimulatorRodriguez, Ramón January 2007 (has links)
The objective of this thesis work was to implement all the hardware and software necessary to simulate the functionality of a Vector Network Analyzer (VNA). With equipment that is already available, and is common in a measurement station, the most common functions of a VNA were implemented, using an Vector Signal Generator, that provide the signal for testing, and a Vector Signal Analyzer, to make all the amplitude and phase measurements. With these instruments and the appropriate software that control them, the basic functionality of a Vector Network Analyzer can be achieved with a reasonable accuracy. With this system, we can reduce costs, avoiding the need of a real VNA and take advantage off instruments that are already available in a laboratory. A Complete measurement system of all four scattering parameters is proposed at the end of the report for future implementation. With this implementation all the different S-parameter measurements were made with an acceptable accuracy that can be comparable to a commercial VNA.
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Investigation de la dispersion des ondes élastiques dans les milieux micro-structurés : applications aux poutres phononiques / Investigation of elastic wave dispersion in micro-structured media with a focus on phononic strip applicationsCoffy, Etienne 13 December 2017 (has links)
La micro-structuration périodique d’un milieu influence fortement la propagation des ondes élastiques. Ces structures, nommées cristaux phononiques, permettent de manipuler les ondes en les ralentissant, voire en interdisant leurs propagations pour certaines gammes de fréquences appelées bandes interdites. Au cours de la thèse, la dispersion des ondes élastiques dans des structures composées de piliers résonants périodiquement attachés à des poutre structurées a été numériquement et expérimentalement étudiée. Basées sur la combinaison de résonances locales avec des réflexions multiples de Bragg, des poutres phononiques avec de larges bandes interdites ont été obtenues. En particulier, une poutre phononique avec une bande interdite présentant une largeur relative de 94% autour du mégahertz a été fabriquée et caractérisée.Les poutres phononiques ont été utilisées pour améliorer les facteurs de qualité des résonances de défauts insérés en fin, ou entre les poutres. Une amélioration d’un facteur 8 d’une résonance d’un défaut encastrée-libre accroché à une poutre phononique a été démontrée. Cette amélioration est attribuée au confinement de l’énergie mécanique par la poutre phononique dont la bande interdite recouvre la fréquence de résonance du défaut. En parallèle de ces activités, une plateforme pompe sonde hétérodyne femtoseconde a été utilisée pour caractériser la propagation des ondes élastiques à la surface de films minces microstructurés. Une forte anisotropie ainsi qu’une réduction des vitesses des ondes a été mis en évidence. Ces observations ont été reliées aux micro-structurations particulières des films, avec des simulations en éléments finis. / Periodic microstructures in media strongly influences the propagation of elastic waves. These structures, known as phononic crystals, allow the manipulation of waves such as their slowdown, or their prohibition for frequency ranges called band gaps.During the thesis, the dispersion of elastic waves propagating through structures composed of resonant pillars periodically attached to tailored strips was studied. Based on the combination of Bragg scattering and local resonances, phononic strips with large band gaps were achieved. Notably, a phononic strip with a band gap displaying a relative width of 94% in the megahertz range was demonstrated.Phononic strips were then used to ameliorate the resonances’ quality factors for defects inserted at the end, or within the strips. An improvement by a factor of 8 of the resonance quality factor of a beam clamped to a phononic strip was achieved. This improvement was assigned to the mechanical energy confinement linked with the phononic strip, as its band gap overlaps the resonance frequency of the defect.In parrallel to these studies, a femtosecond heterodyne pump probe setup was used to characterize the waves propagation on the surface of microstructured thin films. A strong anisotropy as well as a speed reduction were observed. These observations were linked to the particular microstructures of the films, using numerical simulations performed with the Finite Element Method.
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Nouveau système de contrôle Radiofréquence de micro-algues pour la santé et le bien-être / New Radiofrequency Monitoring of microalgae cultivation for health and welfareZhou, Xi 06 December 2016 (has links)
Le développement des produits à base de polysaccharides issus de microalgues implique une étude poussée des voies biotechnologiques de culture. Afin d'optimiser ces nouveaux produits dès la formation des microalgues, un nouveau système de contrôle non-destructif en ligne et sans contact a été développé dans le cadre de cette thèse. Il s'appuie sur la mesure par induction des propriétés diélectriques (conductivité et permittivité) dans le domaine des radiofréquences (1-400MHz). Ce document montre, qu'à l'échelle d'investigation correspondante, il est possible de suivre aussi bien l'évolution du milieu de culture que la formation d'exopolymères via la mesure de la permittivité complexe de ces matériaux. La preuve de concept a nécessité la mise au point d'un circuit résonant bas coût particulièrement sensible, utilisé en émission-réception, et la résolution théorique et expérimentale d'un problème inverse adapté aux champs proches. Ce système implanté dans un photobioréacteur prototype a permis d'extraire l'évolution de grandeurs caractéristiques propres au suivi de culture de microalgues. Cette thèse s'inscrit dans un projet collaboratif plus large de valorisation d'actifs issus de microalgues avec les sociétés Phycosource, Pronovalg, Bio-EC, et LVMH dans le cadre d'un FUI. / The development of products based on polysaccharides from microalgae involves extensive study of biotechnological ways of cultivation. In order to optimize these new products, from the formation of microalgae, a new non-destructive testing system online and without contact has been developed as part of this thesis. It is based on the measurement by induction of dielectric properties (permittivity and conductivity) in the field of radio frequency (1-400MHz). This document shows that inside the corresponding scale of investigation, it is possible to follow both the evolution of the culture medium and the exopolymer formation, via the measurement of complex permittivity of these materials. The proof of concept, required the development of a resonant low cost system particularly sensitive, used as a transceiver, and theoretical and experimental solution of an inverse problem in near fields. This system that operates in a photobioreactor prototype, was used to extract the evolution of characteristics variables of microalgae cultivation. This thesis is part of a larger collaborative project valuation of assets derived from microalgae with Phycosource companies Pronovalg, Bio-EC, and LVMH as part of a FUI.
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Micro-pocket fission detectors: development of advanced, real-time in-core, neutron-flux sensorsReichenberger, Michael Anthony January 1900 (has links)
Doctor of Philosophy / Department of Mechanical and Nuclear Engineering / Douglas S. McGregor / Advancements in nuclear reactor core modeling and computational capability have encouraged further development of in-core neutron sensors. Measurement of the neutron-flux distribution within the reactor core provides a more complete understanding of the operating conditions in the reactor than typical ex-core sensors. Micro-Pocket Fission Detectors (MPFDs) have been developed and tested previously but have been limited to single-node operation and have utilized highly specialized designs. The development of a widely deployable, multi-node MPFD assembly will enhance nuclear research capabilities. In-core neutron flux measurements include many challenges because of the harsh environment within the reactor core. Common methods of in-core neutron measurement are also limited by geometry and other physical constraints. MPFDs are designed to be small and robust while offering a real-time, spatial measurement of neutron flux. Improvements to the MPFD design were developed based on shortcomings of prior research in which many of the theoretical considerations for MPFDs were examined. Fabrication techniques were developed for the preparation of MPFD components and electrodeposition of fissile material. Numerous arrays of MPFDs were constructed for test deployments at the Kansas State University TRIGA Mk. II research nuclear reactor, University of Wisconsin Nuclear Reactor, Transient REActor Test facility at the Idaho National Laboratory (INL), and Advanced Test Reactor at INL. Preliminary testing of a single MPFD sensor at KSU yielded a linear response to reactor power between 10 kWth and 750 kWth and followed both positive and negative reactivity insertions in real-time. A $1.50 reactor pulse was monitored from the Intra-Reflector Irradiation System, located in reflector region of the KSU TRIGA Mk. II core with 1-ms time resolution. Improved multi-node MPFD arrays were then designed, fabricated, and deployed in flux ports between fuel rods and within an iron-wire flux port which was inserted into the central thimble of the KSU TRIGA Mk. II research nuclear reactor. Work continues to develop MPFDs for deployment at research reactors at INL and elsewhere. Results from the MPFD measurements will be useful for future validation of computational modeling and as part of advanced nuclear fuel development efforts.
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Coronographes spatiaux : Solar Orbiter / Metis, Smese / Lyot, Proba-3 / AspiicsVenet, Melanie 14 April 2011 (has links)
La couronne solaire est la partie de l'atmosphère du Soleil qui s'étend de la photosphère (surface solaire d'où sont émis les photons) jusque dans le milieu interplanétaire. Sa compréhension relève d'un enjeu majeur car elle est à l'origine de phénomènes qui peuvent perturber les télécommunications, les êtres vivants et même le climat. L'instrument privilégié pour l'observer est le coronographe, système optique occultant le disque solaire au profit de la couronne, un million de fois moins intense. Ma thèse porte sur son étude, en particulier à travers les projets spatiaux :- SOLAR ORBITER, qui doit s'approcher du Soleil à 0.2 unité astronomique (distance Terre-Soleil), permettant ainsi une très haute résolution spatiale ;- SMESE, en coopération avec la Chine, qui étudiera la couronne dans l'infrarouge lointain ;- et ASPIICS, dont l'occulteur externe sera placé à 150 m de l'instrument imageur, permettant d'observer la couronne dans des conditions proches d'une éclipse solaire naturelle.Le premier aspect abordé est la réjection de la lumière parasite instrumentale, dont l'optimisation est une des problématiques majeures en coronographie. Le second concerne les modes d'observation par imagerie en lumière blanche, imagerie monochromatique, et interférométrie, en particulier le Fabry Perot. Le développement et l'amélioration de ces techniques permettra des avancées considérables en terme de résolution et l'accès à la couronne toujours plus proche de la surface du Soleil, lieu encore mal connu où l'activité solaire prend naissance. / The solar corona is the part of the Sun's atmosphere that extends from the photosphere (solar surface where the photons are emitted) into the interplanetary medium. Its understanding is a major issue because it is the source of phenomena that can disrupt telecommunications, living beings and even climate. The most appropriate tool to observe it is the coronagraph, an optical system obscuring the solar disk in favor of the corona, a million times fainter. My thesis deals with its review, particularly through the spaceprojects :- Solar Orbiter, which will approach the Sun at 0.2 astronomical unit (distance between Earth and Sun), allowing a very high spatial resolution ;- SMESE, in cooperation with China, which should study the corona in the Lymanalpha (and far infrared) ;- and ASPIICS, which will observe the corona in conditions close to a natural solar eclipse, with its occulting disk located at 150 m from the imaging instrument.The first point tackled is the rejection of instrumental stray light, whose optimization is one of the major problems in coronagraphy. The second concerns the methods of observation and imaging in white light, monochromatic imaging, and interferometry, in particular the Fabry Perot. The development and improvement of these techniques will allow considerable progress in terms of resolution and access to the corona ever closer to the Sun's surface, the location yet little known where the solar activity originates.
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