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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Real time aero engine signal analysis

Bousfield, Bruce M. January 1988 (has links)
For many years the analysis of dynamic signals obtained from aero engine mounted transducers has been performed either by using real time spectrum analysers within the test facility, or by making high quality tape recordings during engine tests and analysing the data via an off-line main frame computer. Although real time analysers produce the information where it is most needed, they provide no history of events and the results are operator dependent. Analysis from tape recordings enables information extraction algorithms to be performed and tables and graphs of notable events to be printed. However much of this information could be more effectively utilised if produced within the test facility and in real time. This thesis describes the design and development of a real time data acquisition, signal processing and information extraction system ideally suited for engine health and performance monitoring within test facilities. The thesis begins with a detailed description of the problems encountered in dynamic signal analysis in the field of aero engine performance testing, and with an overview of digital signal processing and the latest technology signal processing micro processors that have made this project possible. It then describes the problems encountered and the subsequent solutions found during the design and development of the hardware and software needed for the·high bandwidth data acquisition and fast signal processing algorithms. The fast Fourier transform has been used for very many years in the field of spectrum analysis, ... however this technique has limitations which are overcome by some of the more modern spectrum estimation techniques. This thesis makes an assessment of some of these techniques, noting particularly their performance on aero engine type signals. The results of these tests are recorded and the possible use of the techniques in aero engine analysis is discussed.
12

Novel multifunctional laser diagnostics

Stewart, Neil Andrew January 2013 (has links)
The research presented in this thesis set out to contribute to knowledge seeking to advance the state-of-the-art in laser based, multi-functional, non-invasive diagnostic systems. The results of the work have contributed to the development of methodological generic approaches to the development of devices using light to detect and analyse biomarkers relevant to human health and disease conditions. Following the development of methodologies the research then progresses to examine in-vivo the potential of the integrated spectroscopic technologies to detect changes and rhythms in the micro-vasculature of the skin relevant to the response of the subjects to emotional and physical stress. The results uncover myogenic rhythm synchronisation as a potential marker of adaptive response. The complexity of monitoring and interpreting key biomarkers of metabolism, NADH and FAD and the derived redox ratio is addressed in detail. Analysis of results of around 3,000 functional scans, including tissue oxygen saturation and laser Doppler flowmetry, provides new insights into bio-technological issues. The challenges identified with biological characteristics include sampling zones and physiological features of the skin. Technological, photonics, electronics and computing challenges emerge from the results. These should be considered in advancing the integration of bio-photonic technologies toward realising meaningful diagnostic poly-bio-markers relevant to developing algorithms capable of delivering consistent, reliable and meaningful diagnostic information with utility in clinical practice for early diagnosis of disease conditions such as cancers and cardio-vascular diseases in individuals from the global population. The results have been published in peer-reviewed international journals and presented at major international conferences in the field.
13

Caractérisation de deux anneaux dérivés du chromosome 22 découverts en période prénatale à l'aide de techniques de cytogénétique et de génétique moléculaire

Gadji, Macoura. January 1900 (has links) (PDF)
Thèse (M.Sc.)--Université Laval, 2005. / Titre de l'écran-titre (visionné le 14 mai 2007). Bibliogr.
14

Diagnosing subsynchronous vibrations in turbomachinery - stable or unstable

Rajagopalan, Vinayaka Narayanan 15 May 2009 (has links)
No description available.
15

Improved Techniques for High-Throughput Molecular Diagnostics

Curcio, Mario January 2002 (has links)
The amount of information derived from sequencing the humangenome is leading to an exponential increase in the rate atwhich genes and genetic disorders are mapped and characterized.As a consequence, the demand for genetic testing is alsodramatically increasing. Screening and assaying methods, otherthan direct sequencing, are gradually becoming available,although with different robustness, sensitivity and throughput.In the work summarized in this thesis, attention was devotedprimarily to the improvement and the development of newtechniques for some of these methods. Considering the role of capillary electrophoresis inmolecular diagnostics and an associated important phenomenon -electroosmotic flow (EOF) - a robust, reproducible procedurefor surface modification of the inner wall of capillaries wasreported (Paper I) and this method was beneficially employed insubsequent projects. The effort to screen and characterize point mutations in theCACNA1A gene, responsible for the Familial Hemiplegic Migraine(FHM) disease, led to the optimization and validation of a verysensitive technique on slab gel called Double Gradient–Denaturing Gradient Gel Electrophoresis (DG-DGGE) (Paper II). A more reliable and robust method forSingle-Strand Conformation Polymorphism analysis (SSCP) bycapillary electrophoresis, making use of neutral pH buffers,was also developed (Paper III), while the next project resulted in thedevelopment of a high-throughput method for assaying knownpolymorphisms by multiplex solid-phase minisequencing inmulti-capillary format using a detection system based on liquidcore waveguiding (Paper IV). As these and other methods, as well as most applications inmolecular diagnostics and molecular biology, depend on thepolymerase chain reaction (PCR), an effort was made to enhancethe throughput of this technology and to minimize reactionvolumes and costs. For this, the concept of a dynamic reactorwas employed, instead of static systems where the reactionmixture is exposed to temperature cycles in a confined space. Acontinuous flow of small-volume reaction mixtures, separated byan immiscible hydrophobic carrier fluid such as aperfluorocarbon, is transported in a hydrophobic tube throughthree zones, which are kept at constant temperatures optimizedfor denaturation, annealing and elongation (Paper V). If combined with a technique for automatedsample loading and collection (Chapter 7), this method should allow veryhigh-throughput miniaturized DNA amplification. A samplehandling concept using hydrophilic anchors is proposed, whichshould also be useful for other miniaturized reactions andchemical processing. Finally, some possible alternative methods are discussed aswell as future trends. <b>Keywords:</b>Amplification, anchor, array, assay,capillary, DGGE, disease, disorder, DNA, droplet, dynamicreactor, electrophoresis, fluorescence, fluorocarbon, gel,genetic alteration, genomics, genotyping, high-throughput,hydrophobic, liquid lid, miniaturized reaction, minisequencing,molecular diagnostics, mutation, PCR, polymerase chainreaction, screening, segmented flow, single nucleotidepolymorphism, SNP, SSCP, test.
16

On-Board Diagnostics over Ethernet

Moradpour Chahaki, Saeed January 2012 (has links)
Modern vehicles are more electrical than mechanical. As the vehicle industry goes on, more mechanical parts are being replaced by electrical components, e.g. x-by-wire. Weight and production costs could be the major factors in this revolution. To ensure the safety and in time response (meeting request’s deadline), the connection between these components is of great importance. Trying to find a protocol and standard that fits the vehicle industry to connect all ECUs, sensors and actuators together is not an easy task, since we are dealing with a system that has got a diverse type of traffic. Safety on the one hand and cost on the other hand are pushing the manufacturers to find the best networking protocol. In this report I am going to investigate the possibility and the risk of implementing on-board diagnostics over Ethernet. UDS (unified diagnostic services) and DoIP (diagnostic communication over Internet protocol) are the protocols that are going to be studied. To be more precise, I will investigate the possibility and the risk of UDS and DoIP implementation. The reason is that with the increasing number of ECUs and volume of data (parameter setting, downloading software, etc.,), the already implemented protocols and standards are not able to answer the required bandwidth. The wide acceptance and high bandwidth of Ethernet on one hand and its low cost infrastructure on the other hand has made Ethernet a candidate for this purpose.  The feasibility of Ethernet for in-vehicle network has already been investigated as I will show in the review of previous works. There are a couple of works that shows by using a suitable protocol in data link layer, we can meet the real-time requirement of a process. By reviewing these previous works we will find out that using Ethernet for vehicle on-board diagnostics is feasible. After investigating risks and manufacturer’s requirements along with worldwide legislations for the vehicle industry I will develop a DoIP gateway according to ISO 13400 which is connected to a CAN bus from one side and to a test tool via Ethernet from another side (Fig.1). UDS and DoIP protocols are implemented on both test tool and DoIP gateway. The practical part of the work is a complementary step in risk investigation that will be analysed. Having Ethernet as a carrier allows us to make use of different protocols, based on different needs like bandwidth, latency and real-time characteristics. This fact allows the network to have multi-type data which is usually the case with in-vehicle network. That is, we can use Ethernet not only for on-board diagnostics but also for other in-vehicle domains, such as the chassis, infotainment and comfort. At the end I will propose two models that will help the designers in this domain.
17

Demodulation Techniques in Gearbox Diagnostics

Meisingseth, Andreas January 2012 (has links)
This thesis covers the scope of one out of many ways to diagnose gearboxes, demodulating the excited vibrational signals to enhance fault detection and identification. The topic is not only of academic interest since the achievements that can be made by successful machine condition monitoring in the industry. It has a potential value that is close to be absurd, for example unplanned production stops is commonly known to be one of the worst nightmares for manufacturing companies and if one can detect faults in early stages one can improve the possibilityto plan a production stop and therefore increase the profit. Four demodulation algorithms were developed and implemented in MATLAB on data characterized by close to stationarity and distinctive energy centered around the harmonics of the gearmesh frequency. The resulting algorithms for narrowband phase and amplitude demodulation was shown to outperform Hilbert transform based phase and amplitude demodulation algorithms in gearbox diagnostics. One of the goals with the thesis was therefore reached; demodulation algorithms were developed and implemented on data. A comparison of these algorithms was done and a conclusion of which demodulation technique is superior was done. Experimental work was carried out on a test-rig and both local and distributed faults were introduced to two gearboxes, one kind of fault per gearbox. However, the data acquired from the test-rig showed severe non-stationarity and smeared spectrum properties even when angular resampling was performed and therefore a major drawback of the demodulation techniques was exploited since the methods for demodulation in this thesis are not applicable for signals with smeared spectrums. The other goal was therefore not accomplished; to distinguish a local fault from a distributed fault in data acquired by experimental work by applying the selected demodulation techniques.
18

Diagnosing subsynchronous vibrations in turbomachinery - stable or unstable

Rajagopalan, Vinayaka Narayanan 15 May 2009 (has links)
No description available.
19

Improved Techniques for High-Throughput Molecular Diagnostics

Curcio, Mario January 2002 (has links)
<p>The amount of information derived from sequencing the humangenome is leading to an exponential increase in the rate atwhich genes and genetic disorders are mapped and characterized.As a consequence, the demand for genetic testing is alsodramatically increasing. Screening and assaying methods, otherthan direct sequencing, are gradually becoming available,although with different robustness, sensitivity and throughput.In the work summarized in this thesis, attention was devotedprimarily to the improvement and the development of newtechniques for some of these methods.</p><p>Considering the role of capillary electrophoresis inmolecular diagnostics and an associated important phenomenon -electroosmotic flow (EOF) - a robust, reproducible procedurefor surface modification of the inner wall of capillaries wasreported (<i>Paper I</i>) and this method was beneficially employed insubsequent projects.</p><p>The effort to screen and characterize point mutations in theCACNA1A gene, responsible for the Familial Hemiplegic Migraine(FHM) disease, led to the optimization and validation of a verysensitive technique on slab gel called Double Gradient–Denaturing Gradient Gel Electrophoresis (DG-DGGE) (<i>Paper II</i>). A more reliable and robust method forSingle-Strand Conformation Polymorphism analysis (SSCP) bycapillary electrophoresis, making use of neutral pH buffers,was also developed (<i>Paper III</i>), while the next project resulted in thedevelopment of a high-throughput method for assaying knownpolymorphisms by multiplex solid-phase minisequencing inmulti-capillary format using a detection system based on liquidcore waveguiding (<i>Paper IV</i>).</p><p>As these and other methods, as well as most applications inmolecular diagnostics and molecular biology, depend on thepolymerase chain reaction (PCR), an effort was made to enhancethe throughput of this technology and to minimize reactionvolumes and costs. For this, the concept of a dynamic reactorwas employed, instead of static systems where the reactionmixture is exposed to temperature cycles in a confined space. Acontinuous flow of small-volume reaction mixtures, separated byan immiscible hydrophobic carrier fluid such as aperfluorocarbon, is transported in a hydrophobic tube throughthree zones, which are kept at constant temperatures optimizedfor denaturation, annealing and elongation (<i>Paper V</i>). If combined with a technique for automatedsample loading and collection (<i>Chapter 7</i>), this method should allow veryhigh-throughput miniaturized DNA amplification. A samplehandling concept using hydrophilic anchors is proposed, whichshould also be useful for other miniaturized reactions andchemical processing.</p><p>Finally, some possible alternative methods are discussed aswell as future trends.</p><p><b>Keywords:</b>Amplification, anchor, array, assay,capillary, DGGE, disease, disorder, DNA, droplet, dynamicreactor, electrophoresis, fluorescence, fluorocarbon, gel,genetic alteration, genomics, genotyping, high-throughput,hydrophobic, liquid lid, miniaturized reaction, minisequencing,molecular diagnostics, mutation, PCR, polymerase chainreaction, screening, segmented flow, single nucleotidepolymorphism, SNP, SSCP, test.</p>
20

Investigation of the shear layer versus the last closed flux surface on TEXT-upgrade

Craig, Joseph Lackey. January 2001 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2001. / Vita. Includes bibliographical references. Available also from UMI/Dissertation Abstracts International.

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