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1

Kachkachi, Noreddine. "Spectromètre RQN à base d’un SoC-FPGA : Conception numérique, vérification fonctionnelle et validation expérimentale". Electronic Thesis or Diss., Université de Lorraine, 2024. http://www.theses.fr/2024LORR0053.

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La Résonance quadrupolaire Nucléaire (RQN) est une technique de spectroscopie radio fréquence très utile pour l'identification non invasive et l'analyse de produits chimiques. Cependant cette technique souffre de plusieurs problèmes, notamment de la faible sensibilité et pose beaucoup de défis quand à la conception de l'instrumentation RQN. Afin de relever ces défis techniques et d'améliorer davantage les performances, nous proposons de développer ici, une nouvelle approche qui consiste en la numérisation et l'optimisation de l'architecture électronique en vue d'améliorer la sensibilité. Ainsi, j'ai réalisé dans le cadre de cette thèse, la conception, la vérification fonctionnelle ainsi que la validation expérimentale d'un spectromètre RQN à base d'un SoC-FPGA où l'essentiel de la fonctionnalité matérielle et logicielle est intégré sur une seule puce. Les modules que j'ai conçus et intégrés sur le SoC-FPGA sont: un générateur d'impulsions haute résolution, un module d'acquisition entièrement numérique avec un traitement de signal temps réel et FID stocké sur mémoire externe DDR, un module d'émission numérique entièrement contrôlé et un module de débogage. En plus de la partie logique programmable, j'ai développé et intégré sur le processeur embarqué du SoC-FPGA deux applications Linux pour piloter le spectromètre. La conception de cette architecture, numérique et optimisée, a permis ainsi de se doter d'un nouveau spectromètre de performances et de fonctionnalités remarquables par rapport à l'état de l'art et par rapport aux spectromètres portables commerciaux. La miniaturisation et la numérisation ont permis aussi de réaliser la compacité du système et ainsi d'ouvrir la porte à de nouvelles applications industrielles. En plus, la réalisation de cette nouvelle architecture à base de SoC-FPGA, a apporté une amélioration de la sensibilité grâce à une meilleure immunité aux bruits et à une chaîne d'acquisition entièrement numérique avec un traitement de signal performant. Le spectromètre réalisé a été testé avec succès sur plusieurs échantillons de référence ainsi que sur des échantillons à applications pharmaceutiques tels que le paracétamol et le nitroprussiate de sodium
Nuclear Quadrupolar Resonance (NQR) is a radio frequency spectroscopy technique that is very useful for non-invasive identification and analysis of chemical products. However, it suffers from low sensitivity which makes its instrumentation very challenging. In order to tackle these challenges and enhance the performances, especially sensitivity,we present in this thesis a solution which consists in a SoC-FPGA based compact spectrometer, where all the major digital hardware and software modules are integrated on a single System On Chip, including : a high pulse width resolution pulse programmer, a fully controllable transmitter, an acquisition module with real time digital signal processing, and storage of the acquired signal in an external memory, and a hardware debugger, in addition to embedded Linux applications that drive the spectrometer functionalities. This digital integration and miniaturisation brought noticeable performances of the spectrometers' overall functionality, especially in terms of sensitivity and portability. The designed spectrometer was successfully tested on several representative samples
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2

Skolnik, Derek. "Building instrumentation". Diss., Restricted to subscribing institutions, 2008. http://proquest.umi.com/pqdweb?did=1790313721&sid=1&Fmt=2&clientId=1564&RQT=309&VName=PQD.

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3

KASSAB, GHAZI. "Etude des milieux poreux par rmn : instrumentation specifique et etude des temps de relaxation". Paris 6, 1992. http://www.theses.fr/1992PA066524.

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Le travail decrit dans cette these avait pour objectif d'adapter l'appareil d'irm 0,1 t de l'institut d'electronique fondamentale (ief) a l'etude des milieux poreux, puis de deduire les methodes d'imagerie possibles pour ces materiaux. Les bases physiques de l'irm et la structure de l'appareil d'imagerie de l'ief sont rappelees dans le premier chapitre. Dans le second chapitre, nous decrivons la conception et la realisation d'un systeme radio-frequence (rf) specifique a l'etude des milieux poreux. Nous montrons que ce systeme rf permet d'ameliorer l'efficacite de l'antenne rmn et l'homogeneite du champ rf pendant l'emission. Pendant la reception, en utilisant la technique de surcouplage inductif, on a pu elargir la bande passante du systeme de reception, sans degradation notable du rapport signal-sur-bruit, d'un facteur 11 par rapport a la methode d'adaptation a 50. Le troisieme chapitre comporte deux parties: dans la premiere partie nous presentons une etude detaillee des temps de relaxation dans les milieux poreux, en fonction du champ b#0, et du parametre t#c#p caracteristique de la sequence cpmg. Cette etude nous permet de distinguer trois regimes de relaxation transversale en fonction de la taille des pores. Nous montrons qu'une methode d'imagerie differente est appropriee a chaque regime. La deuxieme partie de ce chapitre est consacree a l'etude des temps de relaxation en fonction de la mouillabilite des echantillons. Nous montrons a l'aide de cette etude qu'il est possible d'obtenir une cartographie de mouillabilite par rmn
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4

Halidi, El Mohamed. "Études RMN et IRM en champ proche : développements et applications". Thesis, Montpellier 2, 2013. http://www.theses.fr/2013MON20261/document.

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Le principe de la RMN repose sur la détection de l'aimantation provenant de spin des noyaux atomiques tels que 13C, 31P et 1H. L'échantillon est placé dans un champ magnétique statique, qui polarise l'ensemble des spins. Ces derniers sont ensuite excités par les impulsions radiofréquences (environ un mètre de longueur d'onde), qui font basculer l'aimantation de ces spins dans le plan transversal. Lorsque l'aimantation retourne à sa position d'équilibre, il génère un champ électromagnétique qui est classiquement détecté par une antenne réceptrice (bobine avec un circuit d'accord/d'adaptation) à couplage inductif. Dans ce travail, nous proposons l'utilisation d'une sonde de taille micrométrique placée au voisinage de l'objet d'intérêt, à une distance bien plus courte que la longueur d'onde du signal de RMN rayonné. Notre microsonde présente des caractéristiques innovantes (i) un couplage capacitif (composante du champ électrique), (ii) une dimension réduite pour un positionnement précis, qui assure la détection du signal de RMN de l'échantillon et (iii) une détection à large bande, ce qui permet de l'utiliser pour détecter différents noyaux sans être accordée à la fréquence de Larmor. Pour vous présenter cette nouvelle alternative, les outils nécessaires à la compréhension de ce travail, en l'occurrence le principe de la RMN et de l'IRM et une introduction de la théorie du champ proche électrique sont donnés. Nous avons fait aussi un état de l'art des méthodes et techniques existant pour mesurer le signal RMN afin de recenser les avantages qu'un tel système (méthode : couplage capacitif et dispositif : microsonde de champ proche) peut apporter à la technique RMN. Ensuite, nous avons caractérisé notre microsonde pour améliorer sa détection hyper localisée, nous avons démontré que le signal RMN récupéré par notre antenne peut être décrit par l'expression du champ proche électrique :E(x, z) = A(Kz ) exp(i(z/L)) exp(−x/L) + Terme Propagatif. Enfin, nous avons appliqué notre système à des études RMN comme la spectroscopie, la relaxométrie ou encore de l'imagerie RMN. Nous avons aussi énoncé certains projets potentiels à la continuité de ce travail
The principle of NMR is based on the detection of the magnetization originating from the spin of atomic nuclei such as 13C, 31P and 1H. The sample is placed in a static magnetic field, which polarizes the ensemble of spins and it is excited by radiofrequency pulses (wavelength about one meter), that tilt the axis of the magnetization. When the magnetization returns to equilibrium, it generates an electromagnetic field which is classically detected by a receiving antenna (coil with atuning/matching circuit) in inductive coupling.In this work, we propose the use of a micrometer-sized probe positioned in the vicinity of the object of interest, at a distance well shorter than the wavelength of the radiated NMR signal.Our microprobe presents innovative characteristics (i) a capacitive coupling (electric field component), (ii) reduced dimensions for an accurate positioning, which ensure the detection of NMR signal from the sample and (iii) it has a broadband, which allows use to detect any nuclei without being tuned to the Larmor frequency.To introduce you this new alternative, the tools necessary to the understanding of this work, in this case the principle of NMR/MRI and an introduction of the theory of the electric near field are given initially.We made also a state of the art of existing methods and techniques for measuring the NMR signal to identify the benefits that such a system (method : capacitive coupling and device : microprobe near field) can bring to the NMR technique.Then, we have characterized our microprobe to enhance its localized detection due to its small size (127 μm in diameter and 2mm in length). In this stage of characterization, we demonstrated that the NMR signal recovered by our antenna can be described by the electric near field expression :E(x, z) = A(Kz ) exp(i(z/L)) exp(−x/L) +Propagative TermFinally, we applied our system to make NMR studies such as spectroscopy, the relaxometry and NMR Imaging. We have outlined some potential projects to the continuity of this work
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Pagnano, Marco Aurelio de Oliveira. "Automação de um espectrômetro por ressonância magnética nuclear pulsada". Universidade de São Paulo, 1993. http://www.teses.usp.br/teses/disponiveis/54/54132/tde-19082014-101639/.

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Este trabalho consistiu na automação do espectrômetro de Ressonância Magnética Nuclear Pulsada existente no laboratório dos professores José Pedro Donoso e Claudio José Magon. Foram efetuados circuitos adicionais e melhorias no equipamento que eles possuíam, à nível de hardware e software. Foram construídas e programadas interfaces paralelas que ligam o microcomputador a um gerador de pulsos, fabricado pela Tecmag Inc., e a um digitalizador rápido (10 ns) Nicolet 430. O programador de pulsos pode acionar independentemente 75 linhas durante o intervalo de tempo subdividido em 2048 eventos, também independente. O software desenvolvido permite a programação de todas as linhas e eventos de forma eficiente e prática. Foi todo escrito em linguagem C, é modular, portátil, e permite a geração de seqüências de pulsos sofisticadas e também o controle da aquisição e transferência de dados
This work describes the Project developped to automatize the pulsed nuclear magnetic resonance spectrometer housed in the laboratory of the professors José Pedro Donoso e Cláudio José Magon. To satisfy our needs we have improved their old equipment, at the level of hardware and software. Were built and programmed the parallel interface between the microcomputer and a pulse programmer made by Tecmag Inc. and with a fast digitizer (10 ns) Nicolet 430. The pulse programmer can control 75 independent output channels during 2048 time intervals. The software we developped allow us to control the whole pulse sequence on a very efficient and practical way. It was written in C-language, and provides the timing signals necessary to generate sofisticated pulse seqüencies, the data acquisition and data transfer to the host computer
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Bolat, Murat. "Instrumentation tool for context-aware optimization". Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 64 p, 2009. http://proquest.umi.com/pqdweb?did=1885467641&sid=5&Fmt=2&clientId=8331&RQT=309&VName=PQD.

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7

Kienlin, Markus von. "Instrumentation et méthodologie en spectroscopie RMN in vivo suppression de l'eau, édition de spectre et localisation spatiale /". Grenoble 2 : ANRT, 1988. http://catalogue.bnf.fr/ark:/12148/cb37619193v.

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Kienlin, Markus von. "Instrumentation et méthodologie en spectroscopie RMN du proton in vivo : suppression de l'eau, édition de spectre, localisation spatiale". Grenoble INPG, 1988. http://www.theses.fr/1988INPG0071.

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9

Karakaya, Yeliz. "Instrumentation for microscale measurement and characterization of bio-fibers". Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file 2.65 Mb., 112 p, 2006. http://proquest.umi.com/pqdlink?did=1037889801&Fmt=7&clientId=8331&RQT=309&VName=PQD.

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10

Laurent, Guillaume. "Increasing solid-state NMR sensitivity : instrumentation, fast acquisitions and signal processing". Electronic Thesis or Diss., Sorbonne université, 2020. http://www.theses.fr/2020SORUS183.

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La Résonance Magnétique Nucléaire (RMN) en phase solide souffre d’une faible sensibilité, malgré les récentes améliorations. Les approches instrumentales, d’acquisition rapide et de traitement du signal ont été examinées afin de remédier à ce défaut le plus efficacement possible. Premièrement, les microbobines (bobine en rotation à l’angle magique, MACS) ont été placées dans un rotor et couplées inductivement à la bobine de la sonde standard. Un gain en temps de ~ 5 a été obtenu sur des microquantités avec une masse m ~ 100-200 µg. Deuxièmement, le temps d’acquisition a été diminué grâce aux échos Carr-Purcell-Meiboom-Gill (CPMG) pour l’acquisition directe. Nous avons produit un programme Python pour traiter les données soit en utilisant les méthodes standard de peigne ou de superposition, soit avec une méthode de débruitage. Un gain en temps de ~ 3-100 a été possible. Troisièmement, l’échantillonnage non-uniforme (NUS) a été choisi comme un moyen de diminuer le temps d’acquisition des expériences multi-dimensionnelles. L’échantillonnage Poisson s’est avéré le meilleur choix pour limiter les artefacts, tandis que l’échantillonnage hybride s’est révélé efficace sur les spectres présentant à la fois des pics larges et fins. Un gain en temps de ~ 4 a été obtenu. Quatrièmement, les spectres ont été traités avec le débruitage par décomposition en valeurs singulières (SVD). Nous avons mis en avant une surestimation des pics gaussiens de ~ 20 %. Le seuillage automatique a été mis en place, donnant un gain en temps de ~ 2,3. Enfin, le temps de calcul a été étudié et diminué par ~ 100. Une comparaison entre les unités centrales (CPU) et les cartes graphiques (GPU) a été fournie
Solid-state Nuclear Magnetic Resonance (NMR) is suffering from an intrinsic low sensitivity, despite recent improvements. Instrumentation, fast acquisition and signal processing approaches were investigated to circumvent this drawback as far as possible. Firstly, microcoils (Magic Angle Coil Spinning, MACS) were placed into rotors and inductively coupled to the standard probe coil. A time gain of ~ 5 was obtained for microquantities with a mass m ~ 100-200 µg. Secondly, acquisition time was decreased by mean of Carr-Purcell-Meiboom-Gill (CPMG) echoes for direct acquisition. Adequate processing is required to get the best enhancement from this technique. We provided a Python software to process data either using standard spikelets or superposition methods, or with a denoising method. A time gain of ~ 3-100 was possible. Thirdly, Non-Uniform Sampling (NUS) was chosen as a way to decrease acquisition time of indirect dimensions of multi-dimensional experiments. Poisson sampling revealed to be the best choice to limit artefacts, whereas hybrid sampling proved to be efficient on spectra with both broad and narrow peaks. A time gain of ~ 4 was achieved. Fourthly, spectra were processed with Singular Value Decomposition (SVD) denoising. We highlighted an overestimation of Gaussian peaks by ~ 20 %. Automatic thresholding was implemented, giving a time gain of ~ 2.3. Finally, computation time was decreased by ~ 100 by combining ‘divide and conquer’ algorithm, optimised libraries, hardware instruction calls and single precision. A comparison between Central Processing Units (CPU) and Graphical Processing Units (GPU) was provided
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Rahima, Sidi-Boulenouar. "Dynamic monitoring of water status of plants in the fields under environmental stress : Design of a portable NMR and applied to sorghum". Thesis, Montpellier, 2018. http://www.theses.fr/2018MONTS081/document.

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Aujourd’hui, comprendre comment les plantes réagissent au stress hydrique est essentiel pour relever le défi de développer de nouveaux cultivars et de nouvelles stratégies d’irrigation, compatibles avec le maintien de la productivité des cultures sous les effets néfastes du réchauffement climatique. Dans ce contexte, l’étude des relations eau/plante présente un intérêt majeur pour la modélisation des réponses des plantes et des organes aux contraintes biotiques et abiotiques. Paradoxalement, il existe très peu de méthodes directes et non invasives pour quantifier et mesurer le niveau et le débit de l’eau dans les plantes.Dans le cadre de ce projet, nous rapportons le développement d’une méthodologie innovante basée sur la relaxation par résonance magnétique nucléaire à champ faible (RMN). Un dispositif RMN dédié pour effectuer des mesures RMN sur des plantes vivantes a été construit dans une chambre climatique qui permet un contrôle et une modification minutieuse des paramètres environnementaux pendant l’expérimentation sur des longues périodes au laboratoire. En parallèle, une imagerie RMN complémentaire à haut champ magnétique pour étudier, l’anatomie, la teneur en eau, le transport du phloéme et du xylème chez les plants de sorgho a été réalisé. La combinaison de ces approches nous permet de déterminer des biomarqueurs éco-physiologiques innovants et de concevoir de nouvelles expériences en laboratoire et même dans les champs.Un résultat particulièrement intéressant concerne l’étude de la distribution spatiale de l’eau dans les tiges (nœuds et entrenœuds) à partir de la relaxométrie RMN à faible champ et des images IRM 3D à haute résolution. La modification des paramètres de relaxation RMN au cours du cycle diurne dynamique sera présentée dans des conditions normales et en situation de stress abiotique. Une application directe permet d’extraire des biomarqueurs écophysiologiques qui permettent d’explorer et de modéliser les flux d’eau en période de stress hydrique et d’analyser leur impact sur le développement du sorgho.Notre but ultime est d’effectuer ces études RMN directement dans les champs. Ainsi, un appareil RMN portable fait maison, fonctionnant à 336 kHz est présenté. Le développement et l’optimisation de l’homogénéité d’un aimant résistif et de bobines Radio Fréquence ainsi que des séquences d'impulsions RMN, afin de respecter la polyvalence et les conditions thermiques pour maintenir la plante ,intacte sont décrits en détails. Enfin nous présenterons nos investigations menées avec ce dispositif en laboratoire, dans les serres et dans les champs de sorgho
Today, understanding how plants respond to water stress is essential to meet the challenge of developing new cultivars and new irrigation strategies, consistent with the maintenance of crop productivity with the evidence of global warming. In this context, the study of plant /water relations is of central interest for modeling plant and organ responses to biotic and abiotic constraints. Paradoxically, there are very few direct and non-invasive methods to quantify and measure the level and the flow of water in plants.For this purpose, we report on the development of an innovative methodology based on low-field Nuclear Magnetic Resonance Relaxometry (NMR). A dedicated NMR device to perform NMR measurements on living plants has been built in a climatic chamber that allows a control and careful modification of environmental parameters during experimentation over reliable periods of time at the laboratory. In parallel, complementary NMR imaging at high magnetic field to study, the anatomy, water content, phloem and xylem transport in sorghum plants were performed. The combination of these approaches allows us to determine innovant eco-physiological biomarkers and to design new experiments in the laboratory and even in the fields.One particular interesting result concertns the investigation of the spatial distribution of water stems (node and inter node) from low field NMR Relaxometry and 3D high resolution MRI images. The modification of the NMR relaxation parameters during dynamic diurnal cycle will be presented in normal and abiotic stress conditions. A direct application permits to extract eco-physiological biomarkers which allows to explore and model water fluxes during water stress and to analyze their impact on the development of sorghum plant. Our ultimate goal is to perform these NMR studies directly in the fields. Thus, a home made portable NMR device, working at 336kHz(8mT) is presented. The development and optimization of the homogeneity of a resistive magnet and Radio Frequency coils, NMR pulse sequences in order to respect the versatility and thermal conditions to maintain the plant intact are described in details. Finally we will present our investigations conducted with this device in the laboratory, in the greenhouses and in sorghum fields
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Braz, Daniel Cesar. "Instrumentação para RMN em campo externo nulo com aplicação ao estudo de ligas FeV no estado de ordenação magnética". Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/76/76132/tde-22042010-160250/.

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Esse trabalho foi motivado pela conjugação das necessidades do Laboratório de Ressonância Magnética Nuclear com as características técnicas do autor dessa dissertação. Havia a necessidade urgente no grupo da documentação e melhoria da instrumentação e do software de processamento dos dados já desenvolvidos para a realização de experimentos de Ressonância Magnética Nuclear em campo externo nulo. Ao longo do desenvolvimento desse trabalho, verificouse a necessidade de novos desenvolvimentos, a saber: o desenvolvimento de um software para processamento dos dados e o desenvolvimento da automação do aparato de controle da temperatura dos experimentos (4,2 a 400 K). A partir do software para processamento dos dados desenvolvido em Matlab, é possível processar facilmente o sinal para reconstrução do espectro. O processamento dos dados pode ser feito por duas vias: integrando o sinal no domínio do tempo ou integrando sua Transformada Fourier (FT). Deste modo, o tempo de processamento dos dados foi consideravelmente reduzido. A automação do aparato para o controle da temperatura permite uma interação mais amigável com o sistema do criostato. Finalmente, o espectrômetro de RMN foi utilizado para o estudo de ligas de FeV na fase sigma. Esses experimentos foram realizados de modo a se observar os espectros dos núcleos de 51V (10 - 100 MHz) e suas oscilações quadrupolares em função da concentração de Fe e da temperatura. Com esse estudo, podese confirmar que os espectros são relativos aos núcleos de 51V. As intensidades das cinco linhas observadas são coerentes com as populações de átomos de V em cada um dos cinco sítios (A, B, C, D e E) cristalográficos, assim como determinado por Difração de Nêutrons. O acoplamento quadrupolar medido foi de aproximadamente 312 KHz para todos os sítios estudados.
This work was motivated by the combination of the needs of the Nuclear Magnetic Resonance Laboratory with the technical features of the author of this dissertation. There was an urgent need in the group to document and improve the instrumentation and data processing software already developed to carry out the zero external magnetic field Nuclear Magnetic Resonance experiments. During the development of this work, it was verified the need for new developments, namely: development of software for data processing and development of automation of the apparatus used for the NMR experiments versus temperature. From the software developed for data processing, written in Matlab, it is easily possible processing the signal to reconstruct the spectrum. The data processing can be done in two ways: integrating the signal in the time domain or integrating its Fourier Transform. The processing time of the data was fast. The automation of the apparatus for controlling the temperature allows a more friendly interaction with the cryostat system. Finally, the NMR spectrometer was used to the study of FeV alloys in sigma phase. The experiments were performed to observe the 51V spectra (10 MHz to 100 MHz) and their quadrupolar oscillations, versus of the Fe concentration and temperature. With this study, it was possible to confirm that the spectra are relative to the 51V nuclei. The intensities of the five lines observed are coherent with the population of the V atoms in each of the Five crystallographic site (A, B, C, D e E), as determined by Neutron Diffraction. The quadrupolar couplings measured were found to be approximately 312 kHz for all sites studied.
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Jennerjohn, Nancy Jane. "Instrumentation for the exposure assessment of airborne carbon nanotubes in the workplace". Diss., Restricted to subscribing institutions, 2009. http://proquest.umi.com/pqdweb?did=1998520781&sid=1&Fmt=2&clientId=1564&RQT=309&VName=PQD.

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Reader, Nicole. "Delaware's first long term instrumented bridge a prototypical instrumentation and installation plan /". Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 156 p, 2007. http://proquest.umi.com/pqdweb?did=1338919141&sid=6&Fmt=2&clientId=8331&RQT=309&VName=PQD.

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Ulu, Buket. "Monitoring And Checking Of Discrete Event Simulations". Master's thesis, METU, 2003. http://etd.lib.metu.edu.tr/upload/1053305/index.pdf.

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Discrete event simulation is a widely used technique for decision support. The results of the simulation must be reliable for critical decision making problems. Therefore, much research has concentrated on the verification and validation of simulations. In this thesis, we apply a well-known dynamic verification technique, assertion checking method, as a validation technique. Our aim is to validate the particular runs of the simulation model, rather than the model itself. As a case study, the operations of a manufacturing cell have been simulated. The cell, which is METUCIM Laboratory at the Mechanical Engineering Department of METU, has a robot and a conveyor to carry the materials, and two machines to manufacture the items, and a quality control to measure the correctness of the manufactured items. This simulation is monitored and checked by using the Monitoring and Checking (MaC) tool, a prototype developed at the University of Pennsylvania. The separation of low-level implementation details (pertaining to the code) from the high-level requirement specifications (pertaining to the simuland) helps keep monitoring and checking the simulations at an abstract level.
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Andreeta, Mariane Barsi. "Programação de um sistema de controle de RF e aquisição de dados para um espectrômetro de RMN de baixo custo". Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/76/76132/tde-22052012-173456/.

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Este projeto teve como objetivo a construção e automatização de um espectrômetro de baixo custo que tem como principal aplicação a caracterização de meios porosos. Para realizar a caracterização de um meio poroso é necessário que o campo magnético externo aplicado não seja intenso para diminuir os problemas relacionados com a diferença de susceptibilidade magnética na interface fluido-solido. Por este motivo, foi construído um magneto resistivo de baixo campo, operando na frequência de próton de 2MHz (0.047 Tesla) e de simples design. Para manter o equipamento com custo mais baixo possível foram construídos em laboratório a fonte de alimentação do magneto, um amplificador ajustado para 2MHz e os componentes λ/4 e os softwares necessários. O software desenvolvido tem a finalidade de controlar a placa de geração e aquisição de radiofrequência que foi adquirida pela empresa Spincore, denominada RadioProcessor. Para esta finalidade optou-se pela construção de uma nova API na linguagem C++, utilizando a API original do RadioProcessor como base, de forma a montar um conjunto de funções simples e intuitivas para a utilização do espectrômetro. Além disso, foi realizada a integração de uma linguagem script à biblioteca, que dá acesso ao usuário a todas as funções básicas de programação, permitindo que um usuário com pouca habilidade de programação possa criar um programa para o controle total do equipamento de forma simples e também tornando o software maleável, sendo possível que novas funções sejam integradas. Isso abre espaço para que o equipamento possa ser utilizado para outras aplicações além das citadas anteriormente. Somada à nova biblioteca, uma interface gráfica foi desenvolvida, a qual compreende o programa de controle do equipamento e também funções para tratamento e visualização de dados, como a transformada inversa de Laplace e transformada de Fourier.
The objective of this project was the assembling and automatization of a low cost NMR spectrometer for the characterization of porous media. The study of porous media through NMR spectroscopy requires a low intensity magnetic field in order to avoid the problems related to the difference of magnetic susceptibility on the fluid-solid interface. For that reason, a low field electromagnet, operating on the proton frequency of 2MHz (0.047 Tesla) and of simple design was built. As to keep all the equipment as low cost as possible, the following components were also assembled in laboratory: the magnets power supply, a 2MHz amplifier, the quarter-wave components and the necessary softwares. The goal of the software developed was to control the RF generation and acquisition board, which was acquired from the enterprise Spincore, further named RadioProcessor. To achieve this goal, it was decided the development of a new API, in the C++ language, which uses the original boards API as a base in order to assemble a group of functions that are simpler and more intuitive to the end user. In addition, a script language was integrated to the APIs library, allowing users with little programming knowledge to write a program which controls the whole equipment in an easy way and also adding flexibility to the software, as it becomes easy to add new functions. This permits that the equipment be easily changed to include other applications in the future. Finally, a graphical interface was developed, which comprehends the equipment control software and the visualization of the data.
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Sá, Alessandro Aguiar de Castro. "Desenvolvimento de instrumentação para o estudo de materiais magnéticos usando RMN com campo externo zero". Universidade de São Paulo, 2005. http://www.teses.usp.br/teses/disponiveis/76/76132/tde-20112013-210032/.

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Este trabalho de mestrado teve por objetivo a recuperação de um espectrômetro de RMN de dupla-ressonância construído na década de 1980 para o estudo de materiais no estado sólido. Esse espectrômetro foi parcialmente destruído por um raio que atingiu o prédio do IFSC-USP em 2001, tendo sua parte digital inutilizada, a qual envolvia o gerador de pulsos, e o digitalizador e promediador de sinais. Este trabalho envolveu a instalação de uma placa geradora de pulsos e um osciloscópio digital, ambos comerciais, controlados por um computador executando programas elaborados por nosso grupo. Embora o espectrômetro permita a implementação de técnicas de RMN de alta resolução de dupla-ressonância para o estudo de materiais no estado sólido, os primeiros experimentos de RMN foram realizados com materiais magnéticos, os quais permitiram sua execução sem a utilização do magneto supercondutor. No momento, esse espectrômetro encontra-se em fase de aprimoramento e testes de desempenho e já tornou possível a obtenção de resultados importantes em materiais magnéticos
The objective of this work was to repair and upgrade a double-resonance NMR spectrometer assembled in the 80s for studying solid-state materials. In 2001 this instrument was damaged by an atmospheric discharge that destroyed its digital modules, i.e., the pulse generator, digitizer, and averager. The work reported on here involved installing a new pulse-generator board and a programmable digital oscilloscope, both commercially available. These are computer-controlled by software developed by our research group. Although the spectrometer allows the use of double resonance NMR techniques for studying solid-state materials, the first experiments were done with magnetic materials, which required no superconducting magnet. Presently, the spectrometer is still being tested and improved. Even so, it is already capable of yielding important data in the study of magnetic materials
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Chitikeshi, Sanjeevi. "Intelligent instrumentation and a robust dynamic model for an ultrasonic navigation system for improved neuro-surgery /". Available to subscribers only, 2007. http://proquest.umi.com/pqdweb?did=1456292241&sid=11&Fmt=2&clientId=1509&RQT=309&VName=PQD.

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May, John Joseph. "Imaging the spectral earth an historical epistemology of scientific instrumentation and geographic perception in urban climatology /". Diss., Restricted to subscribing institutions, 2008. http://proquest.umi.com/pqdweb?did=1779835141&sid=11&Fmt=2&clientId=1564&RQT=309&VName=PQD.

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Mares, David M. "Developmental laboratories for biomedical instrumentation and digital signal processing with virtual instrument technology and diverse software techniques". Laramie, Wyo. : University of Wyoming, 2006. http://proquest.umi.com/pqdweb?did=1292461511&sid=1&Fmt=2&clientId=18949&RQT=309&VName=PQD.

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Wright, Shelley Adams. "A spatially resolved kinematic study of high redshift star forming galaxies development and use of adaptive optics instrumentation /". Diss., Restricted to subscribing institutions, 2008. http://proquest.umi.com/pqdweb?did=1692099821&sid=1&Fmt=2&clientId=1564&RQT=309&VName=PQD.

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Dang, Phuc Hung. "Développement d’aimant bas champ pour RMN Portable : Conception et construction". Thesis, Lyon, INSA, 2015. http://www.theses.fr/2015ISAL0007/document.

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Les travaux menés au cours de cette thèse porté sur le développement d’un aimant pour système de RMN portable. Une homogénéité élevée a été recherchée tout en maintenant le champ magnétique statique B0 aussi élevé que possible (100ppm, 0.12T). Les dimensions de l’aimant sont prédéfinies ainsi que celles de la zone d'intérêt fonction de la taille des aimants permanents utilisés. Ce type de système est dédié à la recherche biomédicale et agroalimentaire. Les travaux présentés ont consisté, à discuter dans un premier temps un certain nombre des paramètres des matériaux magnétiques essentiels à la construction d’aimants de RMN portables. Plus particulièrement le choix des aimants permanents, utilisant un matériau tels que le NdFeB a été justifié. Une combinaison entre portabilité, prix et sensibilité a abouti à la conception d’un prototype d’aimant portable pour appareil RMN à partir d’un système simple d’arrangement de 24 aimants permanents. Le champ magnétique et l'homogénéité de ce système ont été calculés et simulés à l’aide du logiciel Ansys puis les résultats obtenus ont été vérifiés avec le logiciel Radia. Une nouvelle méthode de shim pour augmenter l'homogénéité et corriger les imperfections du champ B0 a été aussi introduite. La position des aimants de shim a fait l’objet d’une optimisation avec le logiciel Radia. Sur la base de ces résultats, un prototype a été réalisé. Les résultats des mesures de champ magnétique et de l'homogénéité sont en bonne corrélation avec les résultats obtenus par simulation. Les erreurs de mesure ont été estimées et une précision suffisante a été atteinte compte tenu des tolérances portant à la fois sur les caractéristiques et sur la fabrication des aimants. Un autre aimant basé sur la configuration Mandhalas (Magnet Arrangement for Novel Discrete Halbach Layout) a fait l’objet d’une étude comparative, portant sur deux configurations utilisant des aimants de formes circulaires et de formes carrés, a été effectuée par simulation 2D (sur la base de trois critères : la masse, l'homogénéité et l'intensité du champ magnétique). Les Mandhalas fabriqués à partir d’aimants circulaires permettent d’avoir de meilleurs résultats (0.32T, 178ppm). D’autre part, la simulation 3D a été faite afin d’évaluer la totalité du système. A partir des résultats obtenus, un système de shim passif a été aussi utilisé dans ce cas et a permis l’augmentation de la zone d'homogénéité de manière significative
This thesis focuses on the development of a magnet system for NMR applications with high homogeneity while maintaining the static magnetic field B0 as high as possible (100 ppm, 0.12T). Due to the application goals, the magnet dimensions are predefined as well as those of the region of interest according to the size of the used permanent magnets. Such system is dedicated to biomedical and agroalimentary applications. The goal of this research has been firstly, the discussion of parameters of magnetic materials which are essential to the construction of portable NMR magnets, and then the choice of the permanent magnet material the “NdFeB” that was explained. A compromise between the portability, price and the sensitivity has led to the design of a prototype of portable NMR magnet with a simple system of arrangement of 24 permanent magnets. The magnetic field and the homogeneity of the system were calculated and simulated by using ANSYS software and these results were correlated to those obtained by the Radia software. A new shim method has been used to increase the homogeneity and correct the field B0 imperfection. Based on these results, a prototype was realized. The results of the magnetic field strength and homogeneity obtained by measurements are in good correlation with the results obtained by simulation. Sufficient accuracy was reached to take into account and correct errors due to manufacturing tolerances of the magnets. Another magnet system based on Mandhalas configuration (Magnet Arrangement for Novel Discrete Halbach Layout) was studied. The comparison between two configurations made from circle and square magnets was performed by 2D simulation (using three criteria: mass, homogeneity and the magnetic field strength). The Mandhalas made from circle magnets give better results (0.32 T, 178 ppm). The 3D simulation was carried out to evaluate the total system. From these results, a passive shim system was also used in this case and the homogeneity significantly increases
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Biscegli, Clovis Isberto. "Espectrômetro para a transferência de polarização elétron-núcleo (efeito Overhauser)". Universidade de São Paulo, 1994. http://www.teses.usp.br/teses/disponiveis/76/76132/tde-01042014-143911/.

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Este trabalho apresenta os detalhes da construção de um espectrômetro para a realização de experimentos de transferência de polarização elétron-núcleo (Efeito Overhauser). São também mostrados: as implementações e modificações feitas no espectrômetro de RPE existente no Laboratório de Ressonância Magnética do DFCM, os circuitos para a construção de um equipamento de RMN para operar de forma pulsado na freqüência fixa de 14 MHz, os desenhos da cavidade de RPE construída para a banda-X (~ 9,2 GHz), os \"softwares\" modificados e desenvolvidos para aquisição de dados, tratamento e reconstrução de imagens. São apresentados os resultados do aumento do sinal de RMN e as imagens obtidas através da Tomografia de Ressonância Magnética, usando amostras menores do que 1 mm de diâmetro (volume ~10 ul), a uma concentração de 2,2 mM de TEMPOL dissolvido em água destilada.
This work describes in details the arrangements that must be accomplished for development of a spectrometer for Dynamic Nuclear Polarization - DNP (Overhauser Effect). Also, the construction project of a 14 MHz pulsed NMR spectrometer and drawings of a homemade EPR cavity for X-band (~ 9,2 GHz) are shown. The DNP probe built for the experiments and modifications done on the EPR spectrometer existing at Laboratory of Magnetic Resonance are discussed in detail. Results on the enhancement of the NMR signal due electron-proton dynamic interactions are presented. NMR imaging of very small objects, 1 mm diameter glass tube filled with 5 ~10 ul of 2,2 mM of free radicals (TEMPOL) solution, obtained through back projection reconstruction NMR tomography method, are presented
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Josse, Gwendal. "De l'adhérence à l'anti-adhérence à travers le Probe Tack". Paris 6, 2001. http://www.theses.fr/2001PA066442.

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Araujo, Roberto Paulo Andrioli de. "Scalable data-flow testing". Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/100/100131/tde-14112014-155259/.

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Data-flow (DF) testing was introduced more than thirty years ago aiming at verifying a program by extensively exploring its structure. It requires tests that traverse paths in which the assignment of a value to a variable (a definition) and its subsequent reference (a use) is verified. This relationship is called definition-use association (dua). While control-flow (CF) testing tools have being able to tackle systems composed of large and long running programs, DF testing tools have failed to do so. This situation is in part due to the costs associated with tracking duas at run-time. Recently, an algorithm, called Bitwise Algorithm (BA), which uses bit vectors and bitwise operations for tracking intra-procedural duas at run-time, was proposed. This research presents the implementation of BA for programs compiled into Java bytecodes. Previous DF approaches were able to deal with small to medium size programs with high penalties in terms of execution and memory. Our experimental results show that by using BA we are able to tackle large systems with more than 250 KLOCs and 300K required duas. Furthermore, for several programs the execution penalty was comparable with that imposed by a popular CF testing tool.
Teste de fluxo de dados (TFD) foi introduzido há mais de trinta anos com o objetivo de criar uma avaliação mais abrangente da estrutura dos programas. TFD exige testes que percorrem caminhos nos quais a atribuição de valor a uma variável (definição) e a subsequente referência a esse valor (uso) são verificados. Essa relação é denominada associação definição-uso. Enquanto as ferramentas de teste de fluxo de controle são capazes de lidar com sistemas compostos de programas grandes e que executam durante bastante tempo, as ferramentas de TFD não têm obtido o mesmo sucesso. Esta situação é, em parte, devida aos custos associados ao rastreamento de associações definição-uso em tempo de execução. Recentemente, foi proposto um algoritmo --- chamado \\textit (BA) --- que usa vetores de bits e operações bit a bit para monitorar associações definição-uso em tempo de execução. Esta pesquisa apresenta a implementação de BA para programas compilados em Java. Abordagens anteriores são capazes de lidar com programas pequenos e de médio porte com altas penalidades em termos de execução e memória. Os resultados experimentais mostram que, usando BA, é possível utilizar TFD para verificar sistemas com mais de 250 mil linhas de código e 300 mil associações definição-uso. Além disso, para vários programas, a penalidade de execução imposta por BA é comparável àquela imposta por uma popular ferramenta de teste de fluxo de controle.
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Goutailler, Florent. "Polarisation dynamique nucléaire a basse température et fort champ magnétique pour des applications biomédicales en imagerie spectroscopique par résonance magnétique". Phd thesis, Université Claude Bernard - Lyon I, 2011. http://tel.archives-ouvertes.fr/tel-00684287.

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Le travail de cette thèse a consisté à concevoir, réaliser et optimiser un montage expérimental de Polarisation Dynamique Nucléaire multi-échantillons pour des applications biomédicales en Imagerie Spectroscopique par Résonance Magnétique. Ce montage est constitué d'un aimant à fort champ magnétique (3,35T), dans lequel se place un système cryog&nique à bain d'hélium (He4) liquide pompé pouvant atteindre des températures infèrieures à 1,2K. Un ensemble d'inserts permet d'effectuer les différentes étapes du processus PDN dont l'irradiation des échantillons par un champ micro-onde (f=94GHz et P=50mW) et le suivi de leur polarisation par Résonance Magnétique Nucléaire. Ce système permet de polariser jusqu'à trois échantillons, de volume proche de 1mL, à des taux de polarisation de quelques pourcents. Il présente une forte autonomie supérieure à quatre heures, autorisant ainsi la polarisation de molécules à longues constantes de temps de polarisation. La possibilité de disposer quasi-simultanèment, après dissolution, de plusieurs échantillons fortement polarisés ouvre la voie à de nouvelles applications dans le domaine de l'imagerie biomédicale.
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Baswell, Michael Alan. "Advanced instrumentation in metal casting applications : a dissertation presented to the faculty of the Graduate School, Tennessee Technological University /". 2008. http://proquest.umi.com/pqdweb?sid=2&vinst=PROD&fmt=6&startpage=-1&clientid=28564&vname=PQD&RQT=309&did=1674416921&scaling=FULL&vtype=PQD&rqt=309&TS=1248288594&clientId=28564.

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