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This thesis deals with automatic localization of thin surgical tools such as needles or electrodes in 3D ultrasound images. The precise and reliable localization is important for medical interventions such as needle biopsy or electrode insertion into tissue. The reader is introduced to basics of medical ultrasound (US) imaging. The state of the art localization methods are reviewed in the work. Many methods such as Hough transform (HT) or Parallel Integral Projection (PIP) are based on projections. As the existing PIP implementations are relatively slow, we suggest an acceleration by using a multiresolution approach. We propose to use model fitting approach which uses randomized sample consensus (RANSAC) and local optimization. It is a fast method suitable for real-time use and it is robust with respect to the presence of other high-intensity structures in the background. We propose two new shape and appearance models of tool in 3D US images. Tool localization can be improved by exploiting its tubularity. We propose a tool model which uses line filtering and we incorporated it into the model fitting scheme. The robustness of such localization algorithm is improved at the expense of additional time for pre-processing. The real-time localization using the shape model is demonstrated by implementation on the 3D US scanner Ultrasonix RP. All proposed methods were tested on simulated data, phantom US data (a replacement for a tissue) and real tissue US data of breast with biopsy needle. The proposed methods had comparable accuracy and the lower number of failures than the state of the art projection based methods.

The following study examines watchmakers and the watchmaking school in Sweden, how these changed during the 20th century. This is done through Geert Hofstede´s theory about levels of analyzes, his different steps to reach culture history. The source material of the study is based on public investigations, scientific articles, newspaper articles, literature and interviews. The purpose of this study is to reach and understand what and why changes occur in the world of watchmaking, and if the watchmaker managed to survive these changes during the 20th century. Results from the study confirm that very little has changed in the watchmaking school, they still use the same methods as they did 300 years ago. The watchmakers in Sweden showed that they had the durability and flexibility to survive several changes, even if the world was in motion during most of the 20th century.

This work deals with the design of universal wireless timer for fire sport disciplines. Fire sport is a group of more than 15 disciplines. There are different ways of time measurement for each discipline. Important part of this work is detailed research of individual disciplines and their requirements at time measurement system and it's accessories. Another part of this work deals with the specification of wireless timekeeping system, which involves suitable partitioning of time measurement system into wirelessly communication modules. The interface for connecting sensors and accessories is also specified. Designed system is suitable for racing and training purposes, it has short installation time. This work also deals with the design of electronics (power and digital circuits) for each module and also with building of prototype, which is tested using prepared scenarios. New findings are evaluated and lead to design of next generation of time measurement system.

In an increasing number of use cases, databases face the challenge of managing irregularly structured data. Irregularly structured data is characterized by a quickly evolving variety of entities without a common set of attributes. These entities do not show enough regularity to be captured in a traditional database schema. A common solution is to centralize the diverse entities in a universal table. Usually, this leads to a very sparse table. Although today's techniques allow efficient storage of sparse universal tables, query efficiency is still a problem. Queries that reference only a subset of attributes have to read the whole universal table including many irrelevant entities. One possible solution is to use a partitioning of the table, which allows pruning partitions of irrelevant entities before they are touched. Creating and maintaining such a partitioning manually is very laborious or even infeasible, due to the enormous complexity. Thus an autonomous solution is desirable. In this paper, we define the Online Partitioning Problem for irregularly structured data and present Cinderella. Cinderella is an autonomous online algorithm for horizontal partitioning of irregularly structured entities in universal tables. It is designed to keep its overhead low by incrementally assigning entities to partitions while they are touched anyway during modifications. The achieved partitioning allows queries that retrieve only entities with a subset of attributes easily pruning partitions of irrelevant entities. Cinderella increases the locality of queries and reduces query execution cost.

EKG registrerar hjärtats elektriska aktivitet genom att registrera spänningsskillnaden mellan olika specifika punkter på kroppsytan. QT-tiden mäts från början av QRS-komplexet till T-vågens slut. QT-tiden visar hur länge den elektriska impulsen som ger en hjärtmuskelkontraktion i hjärtats kamrar varar. En förlängd QT-tid kan uppstå vid bland annat mutationer i gener som kodar för hjärtats jonkanaler. Normalt ska QT-durationen förkortas med högre hjärtfrekvens men vid långt QT-syndrom förkortas inte QT-duration som normalt med ökande hjärtfrekvens. Förlängd QT-tid medför ökad risk för plötslig död. Symptomen vid lång QT-tid är yrsel, hjärtklappning och svimning. Syftet med studien var att validera en ny utvärderingsmetod mot en befintlig metod av QT-mätning under arbete. Den befintliga metoden genomfördes med papper, penna och linjal, medan den nya metoden genomfördes digitalt på en mjukvara, EC-view. Totalt samlades 37 patientdata med misstänkt förlängd QT-mätning in. Ytterligare 10 patientdata från rutin arbets-EKG med andra kliniska frågeställning insamlades med informerat samtycke från patienter. Resultatet erhållen av Pearsons rangkorrelation visar att korrelationen mellan metoderna är 0,90, vilket tyder på en stark korrelation. Bland-Altman analys visar ett p-värde på <0,001 som tyder på att det inte finns någon statistiskt signifikant skillnad i medelvärde mellan QT-mätningarna med digital metod respektive manuell metod på gruppnivå. Några mätningar har avvikit på patientnivå under arbete eller under återhämtningen. Slutsatsen är att metoderna korrelerar på gruppnivå. / ECG registers the heart's electrical activity by registering the voltage difference between specific different points on the body’s surface. The QT-interval measures from the start of QRS-complex to the end of the T-waves. The QT-interval corresponds to the electrical impulse that causes myocardial contraction in the heart’s chambers. An extended QT-time may develop due to mutations in genes that codes for ion channels in the heart. Normally the QT-duration is decreased with a higher heart-rate but in long QT-syndrome the QT-interval does not decrease with the increase in heart rate. Long QT-syndrome increases the risk for sudden death. The symptoms in long QT-syndrome includes dizziness, palpitation and fainting. The aim of the study was to validate a new evaluation method against an existing method of QT-measurements during exercise. The existing method was performed with paper, pencil and ruler, whilst the newer method was performed digitally on a software, EC-view. In total 37 patient data with suspected long QT-syndrome were collected. An additional 10 patient data sets from routine clinical exercise stress tests with other clinical hypothesis were gathered with a written consent obtained the patients. The results obtained by Pearson’s rang correlation shows that the correlation between the methods are 0,90, indicating a strong correlation. Bland-Altman analysis shows a P-value on less than 0,001 which means that there was no statistically significant difference in the average between QT-measurements with digital method respective manual method at group level. Some of the measurements have deviated at the patient level during exercise stress test or after the stress test. The conclusion is that the methods correlate on a group level.

Ein hydrostatisches, hochpräzises Schlauchwaagen-Messinstrument zur kombinierten Bestimmung von Setzungen und Neigungen wurde im Rahmen eines BMWK ZIM-Kooperationsprojektes zur Echtzeitmessung entwickelt. Zunächst wird ein Einblick in das Grundlagenprinzip des hydrostatischen Nivellements gegeben. Darauf aufbauend wird das entwickelte Messprinzip sowie die Systemkonzeption der Hard- und Software vorgestellt. Anhand der Grundlagenversuche wird das technische Know-how, die wissenschaftliche Arbeit der Projektpartner zur Optimierung des Messsystems sowie die Komplexität des Messprinzips dargestellt. Die Funktionalität des Gesamtsystems „HYDRO-LaWa“ sowie die ersten Ergebnisse im Praxiseinsatz werden in drei unterschiedlichen Anwendungsgebieten evaluiert. Das hydrostatische Messinstrument wurde in der dritten Entwicklungsstufe FG-SW-V2 mit hoher Messgenauigkeit und geringer Standardabweichung von 0,1 mm bis 0,2 mm weiterentwickelt. Somit steht in sehr naher Zukunft ein robustes, langzeitstabiles sowie ein in Echtzeit messendes Gesamtsystem für den Markteintritt zur Verfügung.

Les matériaux polymères sont aujourd'hui très présents dans notre environnement et deviennent irremplaçables pour de nombreuses applications : emballage, textile, mobilier,... La connaissance du cycle de vie de ces matériaux, de la production à leur destruction, devient importante pour nos sociétés. Par exemple ces matériaux peuvent émettre des Composés Organiques Volatils qui sont souvent toxiques et leur impact sur le milieu doit être évalué. L’objectif de ce travail de thèse a été de développer une méthode au laboratoire pour identifier et quantifier ces émissions. La difficulté provient de la grande diversité des composés qui peuvent être émis. Par ailleurs la méthode nécessite une fréquence de mesure élevée (temps réel) souvent incompatible avec les techniques actuelles. Une solution analytique couplant un four et un spectromètre de masse haute résolution associé à une méthode d’ionisation chimique contrôlée a été développée. Celle-ci est basée sur un spectromètre FT-ICR compact à bas champ magnétique : BTrap. Les points forts de cette technique sont la très haute résolution en masse qui permet de mesurer la masse exacte des composés et la détection multi composés, simultanée sur toute la gamme de masse. L’ionisation chimique contrôlée permet l'ionisation douce et quantitative des molécules d’intérêt. Le transfert de proton à partir de l’ion H₃O⁺ (PTRMS) a montré son potentiel pour la détection des COV dans de nombreux domaines. Après une présentation du contexte et du besoin, le dispositif expérimental développé est détaillé. La validation de celui-ci pour l'analyse de gaz traces a été effectuée au LPGP, sur un système de dépollution par plasma froid. Les résultats de dégradation de l'acétaldéhyde en fonction des conditions de fonctionnement du réacteur sont présentés.L’ionisation par PTR conduit habituellement à la molécule protonée ce qui simplifie l’identification. Cependant des fragmentations peuvent être observées. L’utilisation d’un précurseur d’ionisation chimique plus lourd et moins réactif que H₃O⁺ pourrait minimiser ces phénomènes. L’utilisation du diflurobenzène protoné a été testée et comparée à celle de l’ion H₃O⁺. Pour cela, des études cinétiques ont été menées sur une série d’alcools connus pour fragmenter avec H₃O⁺, et confirment l'intérêt du nouveau précurseur.Le poly(méthacrylate de méthyle) (PMMA) est un matériau très répandu : plexiglass. Sa dégradation est a priori relativement simple puisqu’il s’agit très majoritairement d’une dépolymérisation, accompagnée de la formation de produits minoritaires. En conséquence, son étude nous a paru intéressante pour la mise au point et la validation de la méthode. La dégradation du PMMA a été étudiée sous atmosphère inerte, puis oxydante. Les résultats obtenus sont présentés : produits émis, bilan en masse, et apport du suivi en temps réel de la dégradation, montrant en particulier que les produits minoritaires sont émis après le monomère.Enfin une dernière partie de conclusion présente les perspectives pour cette nouvelle méthode. / Polymeric materials are now ubiquitous in our environment and become irreplaceable for many applications such as packaging, textile or furniture. Knowledge of the life cycle of these materials from production to destruction becomes important for our societies. For instance, plastics may release Volatile Organic Compounds: VOCs are often toxic and their impact on the environment must be evaluated. The aim of this thesis work is the development of a laboratory method for identification and quantification of these emissions. The difficulty arises from the wide variety of compounds being potentially emitted. Moreover the desired method requires a high measurement rate ("real time") often incompatible with existing techniques. An analytical device coupling a furnace and a high-resolution mass spectrometer associated with a controlled chemical ionization method has been developed. This device is based on a low magnetic field FT-ICR compact mass spectrometer. The strengths of this technique are (i) high mass resolution allowing exact mass measurements, (ii) recording of the whole mass range simultaneously, allowing detection of a large variety of compounds. Controlled chemical ionization allows soft and quantitative ionization of molecules of interest. Proton transfer from H₃O⁺ ion (PTRMS) has shown its potentialities for VOC detection in many areas. After presenting the background and need, the developed experimental device is described in detail.The validation of this instrument for trace gas analysis has been performed at LPGP, using a nonthermal plasma depollution device. The results of acetaldehyde degradation according to operating conditions in the discharge reactor are presented.PTR ionization usually leads to the protonated molecule, so that identification is simplified. However fragmentations are sometimes observed. Use of a chemical ionization precursor ion heavier and less reactive than H₃O⁺ may minimize these drawbacks. Protonated difluorobenzene was selected as a precursor and its reactivity was tested and compared with H3O+ reactivity. In this purpose, kinetic studies were performed on a series of alcohols known for their fragmentation behavior with H₃O⁺. The results confirm the interest of the new precursor.Polymethyl methacrylate (PMMA) is a widespread material: plexiglass. Its degradation process is relatively simple since it consists in predominant depolymerization, along with formation of minor products. Consequently, PMMA study appeared interesting for method development and validation. Thermal degradation of PMMA has been studied under inert, then oxidative atmosphere conditions. The presented results include identification of minor products and mass balance under different temperature conditions. Real-time monitoring of VOC emission showed time differences in emission peaks of MMA monomer and minor products, each of them being emitted slightly later than MMA. Finally, a conclusive part presents the perspectives opened for this new method.

Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-10-31T17:20:21Z No. of bitstreams: 1 2016 - Elisa Vila Nova de Noronha.pdf: 4419781 bytes, checksum: 0804df588af66f56621082802458f769 (MD5) / Made available in DSpace on 2017-10-31T17:20:21Z (GMT). No. of bitstreams: 1 2016 - Elisa Vila Nova de Noronha.pdf: 4419781 bytes, checksum: 0804df588af66f56621082802458f769 (MD5) Previous issue date: 2016-12-21 / For the drilling process to succeed, it is necessary the use of a drilling fluid. The measurement of rheological properties from these fluids becomes important in order to allow good hydraulic gusher maintenance and management. If these measures are taken in an on- line order that will mean agility in decision-making about the maintenance of the properties of the fluid and it will result in savings of thousands of dollars during the drilling of a well. It is in this context that this current report, developed in the UFRRJ laboratory of fluid flow, aims to evaluate the performance of a modified and calibrated process viscometer, making it a unique equipment for conducting real-time measures of apparent viscosity and thixotropy curve. The process viscometer chosen has the geometry of coaxial cylinders being, thus similar to the current workbench equipment used in drilling rigs. The modified viscometer performance was confronted with the rheometer benchtop Haake Rheostress 1. Different compositions of fluids, containing assorted concentrations of viscosifier polymers and suspension solid have been tested. The results indicated that there was an agreement on the results towards a considered error permissible for a viscometer process. The online viscometer brings a pioneering real-time measuring capacity and plotting of rheological behavior curves towards the current technology used in drilling operation. / Para que o processo de perfura??o seja bem-sucedido, ? necess?rio o uso de um fluido de perfura??o. A medi??o das propriedades reol?gicas destes fluidos torna-se importante para permitir uma boa manuten??o e gest?o hidr?ulica do po?o. Se estas medidas forem realizadas de forma online isso significar? agilidade na tomada de decis?o sobre a manuten??o das propriedades do fluido e acarretar? na economia de milhares de d?lares durante a perfura??o de um po?o. ? neste contexto que o presente trabalho, desenvolvido no Laborat?rio de Escoamento de Fluidos da UFRRJ, tem como objetivo avaliar o desempenho de um viscos?metro de processo modificado e calibrado, tornando-o em um equipamento exclusivo, para realizar medidas em tempo real de curva de viscosidade aparente e tixotropia. O viscos?metro de processo escolhido tem a mesma geometria de cilindros coaxiais sendo desta forma semelhante ao atual equipamento de bancada utilizado nas sondas de perfura??o. O desempenho do viscos?metro modificado foi confrontado com o re?metro de bancada Haake Rheostress 1. Foram testadas diferentes composi??es de fluidos contendo concentra??es variadas de pol?meros viscosificantes e s?lidos em suspens?o. Os resultados obtidos indicaram que houve concord?ncia nos resultados diante de um erro considerado admiss?vel para um viscos?metro de processo. Acredita-se que o viscos?metro online avaliado traz uma capacidade pioneira de medi??o em tempo real e plotagem de curvas de comportamento reol?gico diante da atual tecnologia utilizada na ?rea petroqu?mica.

Current lean-premixed fuel injector designs have shown great potential in terms of reducing emissions of pollutants, but such designs are susceptible to combustion instabilities in which aerodynamic instability plays a major role and also has an effect on mixing of air and fuel. In comparison to prototype testing with combustors running in operating conditions, computational approaches such as Large Eddy Simulations (LES) offer a much more cost-effective alternative in the design stage. However, computational models employed by LES require validation by experimental data. This is one of the main motivations behind the present experimental study. Combined particle image velocimetry (PIV) and planar laser induced fluorescence (PLIF) instrumentation allowed simultaneous measurements of velocity vector and a conserved scalar introduced into the fuel stream. The results show that the inner swirl shear layer features two pairs of vortices, which draw high concentration fuel mixture from the central jet into the swirl stream and causes it to rotate in their wakes. Such periodic entrainment also occurs with the characteristic frequencies of the vortices. This has clear implications for temporal variations in fuel/air ratio in a combusting flow; these bursts of mixing, and hence heat release, could be a possible cause of mixing-induced pressure oscillation in combusting tests. For the first time in such a flow, all 3 components of the turbulent scalar flux were available for validation of LES-based predictions. A careful assessment of experimental errors, particularly the error associated with spatial filtering, was carried out. Comparison of LES predictions with experimental data showed very good agreement for both 1st and 2nd moment statistics, as well as spectra and scalar pdfs. It is particularly noteworthy that comparison between LES computed and measured scalar fluxes was very good; this represents successful validation of the simple (constant Schmidt number) SGS model used for this complex and practically important fuel injector flow. In addition to providing benchmark data for the validation of LES predictions, a new experimental technique has been developed that is capable of providing spatially resolved residence time data. Residence times of combustors have commonly been used to help understand NOx emissions and can also contribute to combustion instabilities. Both the time mean velocity and turbulence fields are important to the residence time, but determining the residence time via analysis of a measured velocity field is difficult due to the inherent unsteadiness and the three dimensional nature of a high-Re swirling flow. A more direct approach to measure residence time is reported here that examines the dynamic response of fuel concentration to a sudden cutoff in the fuel injection. Residence time measurement was mainly taken using a time-resolved PLIF technique, but a second camera for PIV was added to check that the step change does not alter the velocity field and the spectral content of the coherent structures. Characteristic timescales evaluated from the measurements are referred to as convection and half-life times: The former describes the time delay from a fuel injector exit reference point to a downstream point of interest, and the latter describes the rate of decay once the effect of the reduced scalar concentration at the injection source has been transported to the point of interest. Residence time is often defined as the time taken for a conserved scalar to reduce to half its initial value after injection is stopped: this is equivalent to the sum of the convection time and the half-life values. The technique was applied to a high-swirl fuel injector typical of that found in combustor applications. Two test cases have been studied: with central jet (with-jet) and without central jet (no-jet). It was found that the relatively unstable central recirculation zone of the no-jet case resulted in increased transport of fuel into the central region that is dominated by a precessing vortex core, where long half-life times are also found. Based on this, it was inferred that the no-jet case may be more prone to NOx production. The technique is described here for a single-phase isothermal flow field, but with consideration, it could be extended to studying reacting flows to provide more insight into important mixing phenomena and relevant timescales.