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Height Estimation of a Blimp Unmanned Aerial Vehicle Using Inertial Measurement Unit and Infrared CameraVilleneuve, Hubert January 2017 (has links)
Increasing demands in areas such as security, surveillance, search and rescue, and communication, has promoted the research and development of unmanned aerial vehicles (UAVs) as such technologies can replace manned flights in dangerous or unfavorable conditions. Lighter-than-air UAVs such as blimps can carry higher payloads and can stay longer in the air compared to typical heavier-than-air UAVs such as aeroplanes or quadrotors. One purpose of this thesis is to develop a sensor suite basis for estimating the position and orientation of a blimp UAV in development with respect to a reference point for safer landing procedures using minimal on-board sensors. While the existing low-cost sensor package, including inertial measurement unit (IMU) and Global Navigation System (GPS) module, could be sufficient to estimate the pose of the blimp to a certain extent, the GPS module is not as precise in the short term, especially for altitude. The proposed system combines GPS and inertial data with information from a grounded infrared (IR) camera. Image frames
are processed to identify three IR LEDs located on the UAV and each LED coordinate is estimated using a Perspective-n-Point (PnP) algorithm. Then the results from the PnP algorithm are fused with the GPS, accelerometer and gyroscope measurements using an Extended Kalman Filter (EKF) to get a more accurate estimate of the position and the orientation. Tests were conducted on a simulated blimp using the experimental avionics.
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Advanced metabolomics for the discrimination of uropathogenic Escherichia coli and their response to antibioticsAlrabiah, Haitham Khalid M. January 2014 (has links)
In recent years, the role of metabolomics has become increasingly more important in the advancement of many research fields including medical studies. Due to lack of metabolomics research in the area of infectious disease and the rise in antibiotic resistance, there is a need for further studies on the modes of antibiotic action and the mechanisms of resistance of pathogenic microorganisms at the metabolome level. This study aimed to investigate effects of DNA synthesis inhibitors on the metabolome of E. coli and to develop a workflow for discrimination between E. coli isolates down to the sub-species level using a variety of methods, which can inform the choice of analytical techniques in metabolomics research. A metabolomics-based approach was used to elucidate metabolic alterations in E. coli K-12 upon challenge with trimethoprim at two pH levels (5 and 7) which mimic human urine acidity. FT-IR spectroscopy was used as a preliminary experiment to produce bacterial fingerprints and GC-MS was applied to generate global metabolic profiles in each condition. At pH 7, as the drug molecules exhibited higher permeability, stronger direct effects of the antibiotic were observed, i.e. decreased levels of nucleotides. Trehalose, an osmoprotectant, was up-regulated in these stress conditions and this up-regulation was mirrored by a decrease in glucose levels. This also correlated with up-regulation of pyruvate-related products (e.g. alanine, citrate and malate). Other off-target related effects were observed such as alterations in the levels of various amino acids upon trimethoprim challenge. This study offered a wider view of drug action at pH levels similar to healthy human urine. A high throughput FT-IR spectroscopy method was developed to discriminate between pathogenic E. coli isolates based on sequence type. This method employed a Bioscreen as a micro-culture incubator instead of traditional sample preparation (shaking flasks), which can be labour intensive and time consuming. Excluding the washing step in the protocol enabled discrimination between isolates of different sequence types. Moreover, a reproducible workflow of lipid analysis based on LC-MS was developed and applied on four pathogenic isolates with different sequence type and susceptibility to ciprofloxacin. This workflow enabled detection of a wide range of lipid classes and determination of significant alterations in lipid levels related to susceptibility to ciprofloxacin. Stressed and control isolates were also analysed using the developed Bioscreen FT-IR approach to assess phenotypic fingerprint differences, which were in line with the LC-MS-ve class distribution. Further investigation by means of four analytical platforms (FT-IR, GC-MS, LC-MS-ve and LC-MS+ve) was applied on E. coli ST131 isolates characterised using classical microbiological tests (virulence factors and metabolic tests). Procrustes transformation was used to compare between the analytical methods and the microbiological tests in terms of their capacity to discriminate between the different isolates. As indicated above, the results from FT-IR and LC-MS-ve were comparable and in line with virulence tests, while GC-MS and metabolic tests were in agreement. Complementary information generated by different analytical techniques and microbiological tests may indicate the requirement for careful selection of the method of investigation and may suggest the need to continue using a combination of methods which are applied to study different features of bacterial physiology.
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The use of analytical techniques for the rapid detection of microbial spoilage and adulteration in milkNicolaou-Markide, Nicoletta January 2011 (has links)
Milk is an important nutritious component of our diet consumed by most humans on a daily basis. Microbiological spoilage affects its safe use and consumption, its organoleptic properties and is a major part of its quality control process. European Union legislation and the Hazard Analysis and the Critical Control Point (HACCP) system in the dairy industry are therefore in place to maintain both the safety and the quality of milk production in the dairy industry. A main limitation of currently used methods of milk spoilage detection in the dairy industry is the time-consuming and sometimes laborious turnover of results. Attenuated total reflectance (ATR) and high throughput (HT) Fourier transform infrared (FTIR) spectroscopy metabolic fingerprinting techniques were investigated for their speed and accuracy in the enumeration of viable bacteria in fresh pasteurized cows' milk. Data analysis was performed using principal component-discriminant function analysis (PC-DFA) and partial least squares (PLS) multivariate statistical techniques. Accurate viable microbial loads were rapidly obtained after minimal sample preparation, especially when FTIR was combined with PLS, making it a promising technique for routine use by the dairy industry. FTIR and Raman spectroscopies in combination with multivariate techniques were also explored as rapid detection and enumeration techniques of S. aureus, a common milk pathogen, and Lactococcus lactis subsp cremoris, a common lactic acid bacterium (LAB) and potential antagonist of S. aureus, in ultra-heat treatment milk. In addition, the potential growth interaction between the two organisms was investigated. FTIR spectroscopy in combination with PLS and kernel PLS (KPLS) appeared to have the greatest potential with good discrimination and enumeration attributes for the two bacterial species even when in co-culture without previous separation. Furthermore, it was shown that the metabolic effect of L. cremoris predominates when in co-culture with S. aureus in milk but with minimal converse growth interaction between the two microorganisms and therefore potential implications in the manufacture of dairy products using LAB. The widespread and high consumption of milk make it a target for potential financial gain through adulteration with cheaper products reducing quality, breaking labeling and patent laws and potentially leading to dire health consequences. The time consuming and laborious nature of currently used analytical techniques in milk authentication enabled the study of FTIR spectroscopy and matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-ToF-MS) as rapid analytical techniques in quantification of milk adulteration, using binary and tertiary fresh whole cows', goats' and sheep's milk mixture samples. Chemometric data analysis was performed using PLS and KPLS multivariate analyses. Overall, results indicated that both techniques have excellent enumeration and detection attributes for use in milk adulteration with good prospects for potential use in the dairy industry.
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Investigating protein modifications using vibrational spectroscopy and fluorescence spectroscopyBrewster, Victoria Louise January 2013 (has links)
Protein based biopharmaceuticals are becoming increasingly popular therapeutic agents. Recent changes to the legislation governing stem cell technologies will allow many further developments in this field. Characterisation of these therapeutic proteins poses numerous analytical challenges. In this work we address several of the key characterisation problems; detecting glycosylation, monitoring conformational changes, and identifying contamination, using vibrational spectroscopy. Raman and infrared spectroscopies are ideal techniques for the in situ monitoring of bioprocesses as they are non-destructive, inexpensive, rapid and quantitative. We unequivocally demonstrate that Raman spectroscopy is capable of detecting glycosylation in three independent systems; ribonuclease (a model system), transferrin (a recombinant biopharmaceutical product), and GFP (a synthetically glycosylated system). Raman data, coupled with multivariate analysis, have allowed the discrimination of a glycoprotein and the equivalent protein, deglycosylated forms of the glycoprotein, and also different glycoforms of a glycoprotein. Further to this, through the use of PLSR, we have achieved quantification of glycosylation in a mixture of protein and glycoprotein. We have shown that the vibrational modes which are discriminatory in the monitoring of glycosylation are relatively consistent over the three systems investigated and that these bands always include vibrations assigned to structural changes in the protein, and sugar vibrations that are arising from the glycan component. The sensitivity of Raman bands arising from vibrations of the protein backbone to changes in conformation is evident throughout the work presented in this thesis. We used these vibrations, specifically in the amide I region, to monitor chemically induced protein unfolding. By comparing these results to fluorescence spectroscopy and other regions of the Raman spectrum we have shown that this new method provides improved sensitivity to small structural changes. Finally, FT-IR spectroscopy, in tandem with supervised machine learning methods, has been applied to the detection of protein based contaminants in biopharmaceutical products. We present a high throughput vibrational spectroscopic method which, when combined with appropriate chemometric modelling, is able to reliably classify pure proteins and proteins ‘spiked’ with a protein contaminant, in some cases at contaminant concentrations as low as 0.25%.
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Avvägning mellan synfält och räckvidd med infraröda sensorer - Nödvändighet eller utvecklingsfråga?Svensk, Fredrik January 2012 (has links)
Att som operatör ha möjlighet att se i ett elektromagnetiskt spektrum som det blotta ögat inte kan upptäcka bidrar till en rad fördelar. Den militära nyttan av IR-sensorer har drivit utvecklingen inom många av dess användningsområden som till exempel målsökare och mörkerkapacitet i totalt mörker. Det finns en svårighet kopplat till IR-sensorer och det är att det måste ske en avvägning mellan dess synfält och dess räckvidd. Syftet med den här uppsatsen är att undersöka vad det är som tvingar tillverkarna av dessa sensorer till att välja mellan dessa två parametrar. Detta för att sedan kunna ha en diskussion om eventuella lösningar och deras bidrag till de två grundläggande förmågorna verkan och underrättelse/information. Två nyare tekniker kommer även att undersökas för att kunna upptäcka alternativa lösningar på problemet.Undersökningen visade på att det största hindret var ett fysikaliskt sådant och detta var kopplat till bildformeringen, optikens fokallängd. En kort fokallängd gav ett brett synfält medan en längre fokallängd gav bättre räckvidd.
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Predictive uncertainty in infrared marker-based dynamic tumor tracking with Vero4DRT / Vero4DRTを用いた赤外線反射マーカーに基づく動体追尾照射の予測誤差Akimoto, Mami 23 March 2015 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第18867号 / 医博第3978号 / 新制||医||1008(附属図書館) / 31818 / 京都大学大学院医学研究科医学専攻 / (主査)教授 鈴木 実, 教授 黒田 知宏, 教授 富樫 かおり / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM
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Zvýšení výtěžnosti BGA opravárenského procesu / Increasing the Yield of BGA Repair ProcessJaníček, Martin January 2015 (has links)
This thesis deals with possibilities of increasing the yield of BGA repair process. First there is mentioned basic problematics and its notions, problems and possibilities. Next it deals with technological aspects of repairing of devices in BGA covers. Also there is mentioned basic problematics of evaluating of yield. There is stated current state of solving the problem and also there is suggested new design of application which would be more optimal for evaluation of the yield of process. This thesis contains results of practical testing of methods of application of flux affecting final quality of solder joints as well as kind of flux which was used. At the end
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Bezdotykové měření povrchových teplot v průběhu soustružení / Contactless measurement of surface temperatures during turningMerenda, Jiří January 2011 (has links)
The goal of this thesis is the incorporation of the contactless measurement of surface temperature among other methods of temperature measurement. Technical preparation for experimental measuring on the machine-tool. Comparison of influence of cutting conditions on the development of surface temperature of workpiece during the machining process with usage of the camera ThermaCAM CS2000. The economical analysis of the contactless measurement of surface temperature is determined in the last part of this thesis.
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Understanding of infrared heating for thermoforming of semi-crystalline thermoplastics / Compréhension de chauffage infrarouge de thermoplastiques semi-cristallinsBoztepe, Sinan 14 December 2018 (has links)
Les thermoplastiques et les composites thermoplastiques sont généralement mis en œuvre par thermoformage et sont alors le plus souvent préchauffés en utilisant un chauffage IR. L’avantage du chauffage radiatif est qu'il permet de chauffer les polymères à cœur grâce au caractère semi-transparent des polymères. Néanmoins, dans le cas des polymères semi-cristallins, le chauffage radiatif est affecté par la structure cristalline et cette thèse a donc eu pour objectif d’améliorer la compréhension de l'interaction entre la structure cristalline et les propriétés optiques dans le but de proposer un modèle prédictif de chauffage de thermoplastiques semi-cristallins.Cette étude répond à une problématique industrielle relative au contrôle de la température des thermoplastiques semi-cristallins dans les procédés recourant au chauffage radiatif. L’optimisation de ces procédés requiert un code de calcul suffisamment robuste pour permettre une bonne prédiction du champ de température tout en conservant des temps de calcul acceptables. Une approche combinée expérimentale et numérique a ainsi été proposée dans le but de modéliser la capacité d’absorption du rayonnement thermique de milieux polymères semi-cristallins et le transfert de chaleur par rayonnement avec changement des phases de cristaux/amorphe. Ces travaux se concentrent sur le PEHD, qui présente un intérêt particulier pour l’entreprise Procter&Gamble.Dans cette thèse, après avoir établi une revue bibliographique mettant en avant les couplages existants entre les phénomènes de diffusion optique, la microstructure des polymères semi-cristallins et la température, une caractérisation et une analyse poussées des propriétés radiatives de deux polyéthylènes sont proposées. Les analyses morphologiques et optiques ont été réalisées à température ambiante et dans des conditions de chauffage afin d’identifier les formations cristallines à l’origine de la diffusion optique dans des polymères semi-cristallins et l’évolution de ce couplage au cours du chauffage. A travers ce travail de recherche, un coefficient d’extinction spectral thermo-dépendant a été proposé afin de décrire le caractère optiquement hétérogène du milieu semi-cristallin par un milieu homogène équivalent. Sur la base de la caractérisation de la capacité d'absorption du rayonnement thermique, un modèle thermique conducto-radiatif thermo-dépendant a été développé. Afin d’évaluer la précision de la modélisation, une méthodologie expérimentale spécifique a été proposée pour mesurer la température de surface par thermographie IR dans le cas du PEHD semi-transparent. L’étape finale a consisté à confronter les résultats issus des simulations numériques basées sur cette modélisation à plusieurs campagnes de mesures expérimentales. Les résultats de ces travaux démontrent la forte influence de la structure morphologique des polymères semi-cristallins sur les transferts de chaleur radiatifs. / Thermoplastics and thermoplastic composites are promising candidates for manufacturing highly cost- effective and environmental-friendly components in terms of rapid forming and recyclability. Thermoforming is extensively used for the processing of thermoplastics where IR heating is widely applied. The major advantage of radiative heating is that the significant portion of radiation penetrates into the semi-transparent polymer media.This thesis focuses on understanding of IR heating of semi-crystalline thermoplastics which aims to analyze the driven mechanisms for radiation transport in optically heterogeneous unfilled semi-crystalline polymer media. Considering the relatively narrow thermoforming window of semi-crystalline thermoplastics, accurate temperature control and close monitoring of temperature field is crucially important for successful forming process. It is thus required to build a numerical model robust enough to allow a good prediction of the temperature field while maintaining acceptable calculation times. In this research work, a combined experimental-numerical approach has been proposed which enables both to characterize the radiation absorption capacity of semi-crystalline polymer media and, to model the radiation heat transfer considering the crystalline/amorphous phases change under heating. This research focuses on a particular polymer - highly crystalline HDPE- which is supported by Procter & Gamble.In this thesis, the literature was reviewed at first for highlighting the existing coupled relation between the optical properties and the crystalline structure of semi-crystalline polymers. The role of crystalline morphology on the optical properties and optical scattering of two type of polyethylene, namely HDPE and LLDPE, were addressed. More specifically, the morphological and optical analyses were performed at room temperature and under heating to determine: which crystalline formations are responsible for optical scattering in semi-crystalline polymer media and, how does their coupled relationship evolve under heating conditions? Hence, one of the key contributions of this research is on establishing a temperature-dependent spectral extinction coefficient of HDPE allowing to describe temperature- dependent radiation absorption capacity of its semi-crystalline medium and, to model radiative transfer considering an equivalent homogeneous medium. Based on the characterization of radiation absorption capacity of semi-crystalline media, a temperature-dependent conduction-radiation model was developed. In order to assess the modeling accuracy, an experimental methodology was proposed for non-invasive surface temperature measurements via IR thermography on semi-transparent polymer media. The final step was to compare the results of numerical simulations with the several IR heating experiments to prove the strong influence of the crystalline morphology on heat transfer.
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A Theory for the Measurement of Internet Information RetrievalMacCall, Steven Leonard 05 1900 (has links)
The purpose of this study was to develop and evaluate a measurement model for Internet information retrieval strategy performance evaluation whose theoretical basis is a modification of the classical measurement model embodied in the Cranfield studies and their progeny. Though not the first, the Cranfield studies were the most influential of the early evaluation experiments. The general problem with this model was and continues to be the subjectivity of the concept of relevance. In cyberspace, information scientists are using quantitative measurement models for evaluating information retrieval performance that are based on the Cranfield model. This research modified this model by incorporating enduser relevance judgment rather than using objective relevance judgments, and by adopting a fundamental unit of measure developed for the cyberspace of Internet information retrieval rather than using recall and precision-type measures. The proposed measure, the Content-bearing Click (CBC) Ratio, was developed as a quantitative measure reflecting the performance of an Internet IR strategy. Since the hypertext "click" is common to many Internet IR strategies, it was chosen as the fundamental unit of measure rather than the "document." The CBC Ratio is a ratio of hypertext click counts that can be viewed as a false drop measure that determines the average number of irrelevant content-bearing clicks that an enduser check before retrieving relevant information. After measurement data were collected, they were used to evaluate the reliability of several methods for aggregating relevance judgments. After reliability coefficients were calculated, measurement model was used to compare web catalog and web database performance in an experimental setting. Conclusions were the reached concerning the reliability of the proposed measurement model and its ability to measure Internet IR performance, as well as implications for clinical use of the Internet and for future research in Information Science.
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