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Mekritthikrai, Kanit. "High Resolution Planet Rendering." Thesis, Linköpings universitet, Institutionen för teknik och naturvetenskap, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-69214.
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Planet rendering plays an important role in universe visualization and geographic visualization. The recent tools and methods allow better data acquisition, usually with very high resolution. However in computer graphics, there is always the limitation on the resolution of geometry and texture due to numerical imprecision. Not many applications can handle high resolution data effectively. This thesis introduces, Implicit Surface Scene, a level of detail scene management inspired by dynamic coordinate system and SCALEGRAPH™ which change over time depending on the current camera position relative to the planet surface. Our method is integrated into Uniview and allows Uniview to render high resolution planet geometry with dynamic texture composition and with a surface positioning system that does not suffer from precision issue.
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Stephan, Sandra. "High-Resolution 3D Ptychography." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2013. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-113219.
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Coherent imaging is a promising method in the field of x-ray microscopy allowing for the nondestructive determination of the interior structure of radiation-hard samples with a spatial resolution that is only limited by the fluence on the sample and the scattering strength of the sample. Ultimately, the achievable spatial resolution is limited by the wavelength of the incoming x-ray radiation. Combining coherent imaging with scanning microscopy to a method called ptychography enables one to also probe extended objects. In this method, a sample is scanned through a defined coherent x-ray beam and at each scan point a diffraction pattern is recorded with a diffraction camera located in the far field of the sample. Neighboring illuminated areas must have a certain overlap to guarantee the collection of sufficient information about the object for a subsequent successful and unique computational reconstruction of the object. Modern ptychographic reconstruction algorithms are even able to reconstruct the complex-valued transmission function of the sample and the complex illumination wave field at the same time. Once the 2D transmission function of a sample is known, it is an obvious step forward to combine ptychography with tomographic techniques yielding the 3D internal structure of an object with unprecedented spatial resolution. Here, projections at varying angular positions of the sample are generated via ptychographic scans and are subsequently used for the tomographic reconstruction. In this thesis the development of 3D ptychography is described. It includes the description of the required experimental environment, the numerical implementation of ptychographic phase retrieval and tomographic reconstruction routines, and a detailed analysis of the performance of 3D ptychography using an example of an experiment carried out at beamline P06 of PETRA III at DESY in Hamburg. In that experiment the investigated object was a Mo/UO2 thin film, which is a simplified model for spent nuclear fuel from nuclear power plant reactors. Such models find application in systematic scientific investigations related to the safe disposal of nuclear waste. We determined the three-dimensional interior structure of this sample with an unprecedented spatial resolution of at least 18 nm. The measurement of the fluorescence signal at each scan point of the ptychograms delivers the two- and three-dimensional elemental distribution of the sample with a spatial resolution of 80 nm. Using the fluorescence data, we assigned the chemical element to the area of the corresponding phase shift in the ptychographic reconstruction of the object phase and to the corresponding refractive index decrement in the tomographic reconstruction. The successful demonstration of the feasibility of the 3D ptychography motivates further applications, for instance, in the field of medicine, of material science, and of basic physical researchKohärente Bildgebung ist eine vielversprechende Methode der Röntgenmikroskopie. Sie ermöglicht die zerstörungsfreie Bestimmung der inneren Struktur von strahlenharten Untersuchungsobjekten mit einer räumlichen Auflösung, die im Prinzip nur von der integralen Anzahl der Photonen auf der Probe sowie deren Streukraft abhängt. Letztendlich stellt die Wellenlänge der verwendeten Röntgenstrahlung eine Grenze für die erreichbare räumliche Auflösung dar. Die Kombination der kohärenten Bildgebung mit der Rastermikroskopie zur sogenannten Ptychographie eröffnet die Möglichkeit, auch ausgedehnte Objekte mit hoher Auflösung zu untersuchen. Dabei wird die Probe mit einem räumlich begrenzten, kohärenten Röntgenstrahl abgerastert und an jedem Rasterpunkt ein Beugungsbild von einer im Fernfeld platzierten Beugungskamera registriert. Die Beleuchtungen benachbarter Rasterpunkte müssen dabei zu einem bestimmten Prozentsatz überlappen, um genügend Informationen für eine anschließende computergestützte und eindeutige Rekonstruktion des Objektes sicherzustellen. Moderne Rekonstruktionsalgorithmen ermöglichen sogar die gleichzeitige Rekonstruktion der Transmissionsfunktion des Objektes und der Beleuchtungsfunktion des eintreffenden Röntgenstrahls. Die Verknüpfung der Ptychographie mit der Tomographie zur 3D-Ptychographie ist der nahe liegende Schritt, um nun auch die dreidimensionale innere Struktur von Objekten mit hoher räumlicher Auflösung zu bestimmen. Die Projektionen an den verschiedenen Winkelpositionen der Probe werden dabei mittels ptychographischer Abrasterung der Probe erzeugt und anschließend der tomographischen Rekonstruktion zugrunde gelegt. In dieser Arbeit wird die Entwicklung der 3D-Ptychographie beschrieben. Das beinhaltet die Beschreibung der experimentellen Umgebung, der numerischen Implementierung des ptychographischen und des tomographischen Rekonstruktionsalgorithmus als auch eine detaillierte Darstellung der Durchführung der 3D-Ptychographie am Beispiel eines Experiments, welches unter Verwendung des modernen Nanoprobe-Aufbaus des Strahlrohres P06 am PETRA III Synchrotronring des DESY in Hamburg durchgeführt wurde. Als Untersuchungsobjekt diente dabei ein dünner Mo/UO2-Film, der ein vereinfachtes Modell für die in Reaktoren von Atomkraftwerken verbrauchten Brennstäbe darstellt und deshalb im Bereich des Umweltschutzes Anwendung findet. Die dreidimensionale Struktur der Probe wurde mit einer - für diese Methode bisher einmaligen - räumlichen Auflösung von 18 nm bestimmt. Die Messung des von der Probe kommenden Fluoreszenz-Signals an jedem Rasterpunkt der Ptychogramme ermöglichte zusätzlich die Bestimmung der zwei- und dreidimensionalen Elementverteilung innerhalb der Probe mit einer räumlichen Auflösung von 80 nm. Anhand der Fluoreszenzdaten konnte sowohl den Bereichen verschiedener Phasenschübe in den ptychographischen Rekonstruktionen der Objektphase als auch den verschiedenen Werten des Dekrementes des Brechungsindex in der tomographischen Rekonstruktion, das entsprechende chemische Element zugeordnet werden. Die erfolgreiche Demonstration der Durchführbarkeit der 3D-Ptychographie motiviert weitere zukünftige Anwendungen, z. B. auf dem Gebiet der Medizin, der Materialforschung und der physikalischen Grundlagenforschung
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Drake, Jeremy J. "High resolution stellar spectroscopy." Thesis, University of Oxford, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.236268.
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Young, Larry Alan. "High resolution monopulse tracking." Master's thesis, University of Central Florida, 1988. http://digital.library.ucf.edu/cdm/ref/collection/RTD/id/73935.
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University of Central Florida College of Engineering ThesisHigh Resolution Radar techniques are applied to the problem of resolving a multiple target array and locating its geometric center without the usual biasing toward the brightest targets. Monopulse radar techniques are combined with high resolution stepped frequency pulse train signal processing in an amplitude tracking radar. A single pulse monopulse system's aimpoint is biased toward the brightest point targets in an array. However, by using a stepped frequency pulse monopulse radar, the cross range distance to each individual scatterer may be found. Unlike the single pulse monopulse system, the aimpoint is independent of the reflectivity of the targets. The geometric center of a multiple scatterer array is found by averaging the cross range components along both axes. For the stepped frequency high resolution monopulse system, the center of each uniquely separated pair of point targets is calculated by examining the cross-correlation function of the sum and difference channels. The autocorrelation of the sum channel is used to normalize the cross-correlation data thereby eliminating the effects of the different targets radar cross sections (RCS). The zero separation term of the error function (DC term) remains biased toward the bigger scatterer, even after normalization. The nonzero terms (AC terms) are the cross range distances from the antenna's boresight to each scatterer and are independent of their RCS. By simply dropping ones together, the aimpoint becomes the unbiased geometric center of the array. The special cases of one, two and three resolvable point scatterers are examined in detail. Analysis of a nondiscrete complex scattering array is not presented, since the requirement of separation pair uniqueness cannot be assumed. The monopulse tracking simulation work was done on an IMB AT using Microsoft Fortran-77.
M.S.
Masters
Engineering
Engineering
105 p.
v, 105 leaves, bound : ill. ; 28 cm.
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Marques, Jefferson Luiz Brum. "High-resolution electrocardiogram analysis." Thesis, University of Sheffield, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.263558.
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Beckett, Martin Gregory. "High resolution infrared imaging." Thesis, University of Cambridge, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.388828.
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JIMENEZ, MARCELO ROBERTO BAPTISTA PEREIRA LUIS. "HIGH RESOLUTION GRAPHIC SYSTEM." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 1992. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=10070@1.
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COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIORNeste trabalho a arquitetura de placas gráficas que usam a tecnologia de varredura (raster scan) é analisada. É discutido então o uso de memórias dinâmicas do tipo VRAM para lidar com o problema do gargalo dos acessos à memória de vídeo. São analisados então alguns módulos importantes que podem ser considerados opcionais numa placa de vídeo, uma vez que a escolha por estes módulos depende da aplicação específica da placa gráfica. Finalmente, apresentamos a descrição do projeto e implementação de uma placa gráfica utilizando o processador gráfico TMS34010 com capacidade para realizar aquisição de imagens.
In the present work, we analyse the architecture of raster- scan graphic boards. We discuss then the use of VRAM dynamic memories to deal with the video memories bottleneck problem. We also analyse a few important modules that may be considered optionals, since the choice of using these modules depends upon the specific use the graphic board will be given. At last, we present the description of the project and implementation of a graphic board using the TMS34010 graphic processor with image acquisition capabilities.
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Ciobanu, Luisa. "High resolution MR microscopy /." The Ohio State University, 2002. http://rave.ohiolink.edu/etdc/view?acc_num=osu1486461246815633.
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Louis, Thibaut. "High resolution CMB physics." Thesis, University of Oxford, 2014. http://ora.ox.ac.uk/objects/uuid:b0d62439-37b8-4aa8-8d17-70141a70572a.
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This thesis presents the measurement of the cosmic microwave background (CMB) power spectrum for the Atacama Cosmology Telescope (ACT) experiment and its polarized upgrade, ACTPol. I present the tools that I have developed for constructing unbiased and nearly optimal statistical estimators. I discuss how to separate the cosmological and the astrophysical signal and how to characterize instrumental systematics. The goal of this work is to obtain accurate power spectra measurement that can be used for cosmological parameter estimation. I first present the analysis of the complete ACT data set. The high resolution of the telescope allows us to recover power spectra to ℓ = 10000. I report the measurement of the power spectra at 148 GHz and 218 GHz, as well as the cross-frequency spectrum between the two channels. The power spectrum measurement is consistent with the ΛCDM model and a basic foreground model. I then present the cross correlation of maps from the Atacama Cosmology Telescope with maps from the Planck satellite in two overlapping regions covering 592 square degrees. I find excel- lent agreement between the two datasets at both frequencies, quantified using the variance of the residuals between the ACT power spectra and the ACT×Planck cross-spectra. The next generation of CMB experiments are focused on measuring its polarization. I present efficient algorithms for CMB lensing simulation and power spectrum estimation for flat-sky CMB polarization maps. Finally, I discuss the first temperature and polarization power spectra measurement from the ACTPol experiment. They are the first attempt to measure the polarization of the CMB at high resolution.
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Kain, Alexander Blouke. "High resolution voice transformation /." Full text open access at:, 2001. http://content.ohsu.edu/u?/etd,189.
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Eriksson, Johannes, Henrik Erlandsson, Jerker Ortman, and Viktor Sköldheden. "High resolution power measurement." Thesis, Uppsala universitet, Elektricitetslära, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-387314.
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Sabbar, Bayan M. "High resolution array signal processing." Thesis, Loughborough University, 1987. https://dspace.lboro.ac.uk/2134/27193.
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This study is concerned with the processing of signals received by an array of sensor elements which may range from acoustic transducers in a sonar system to microwave horns in a radar system. The main aim of the work is to devise techniques for resolving the signals arriving from closely spaced sources in order to determine the presence and direction of these sources.
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Anderson, Darlene. "Studies in high resolution spectroscopy." Thesis, University of British Columbia, 1986. http://hdl.handle.net/2429/26766.
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The ground state microwave spectra of hypochlorous acid (HOCl), carbonylchlorofluoride (FClCO), and N-chlorodifluoromethylenimine (CF₂NCI), have been measured from 8 — 80 GHz and analyzed. The 8[sup 2/sub0] vibrational band of aminoborane (NH₂BH₂) near 1223 cm⁻¹ has been recorded at a resolution of 0.004 cm⁻¹ and analyzed.
HOCl: Rotational constants and quartic centrifugal distortion constants were obtained for the following four isotopic species of hypochlorous acid: D¹⁶O³⁵Cl, D¹⁶O³⁷Cl, H¹⁸O³⁵Cl and H¹⁸O³⁷Cl. The centrifugal distortion constants were combined with vibrational wavenumbers from the literature to determine a valence harmonic force field which was used to calculate an average structure and an estimated equilibrium structure. Effective and full substitution structures have also been evaluated.
FClCO: An extensive set of transitions, to high J and K has been measured
for the two most abundant species, F³⁵CI¹²CO and F³⁷CI¹²CO, which allowed
accurate values for the rotational constants, centrifugal distortion constants and
the chlorine nuclear quadrupole coupling constants to be evaluated for each. An
estimate of the three rotational constants for F³⁵CI¹³CO was made from the four transitions measured, as it exists in natural abundance. Harmonic force constants were produced from ab initio calculations and were used in the determination of its harmonic force field. Effective and average structural parameters have been determined.
CF₂NCI: Rotational constants and quartic centrifugal distortion constants have
been obtained for the two isotopic species CF₂N³⁵CI and CF₂N³⁷CI. The
nuclear quadrupole coupling constants of both ¹⁴N and CI have been evaluated. A partial harmonic force field has been determined from the available data. Both effective and average structural parameters have been obtained and indicate that the structure of CF₂NCI is a hybrid of those of CF₂NF and CCl₂NCl. The nuclear quadrupole coupling constants have provided information about the bonding in the molecule.
NH₂BH₂: Rotational constants and centrifugal distortion constants of the upper
vibrational state 2v₈ have been determined and have confirmed the assignment
of the band. The least squares refinement of the constants has shown an
increasing poorness of fit to the higher K[sub a] transitions which has suggested the
possiblity of Coriolis type perturbations.Science, Faculty of
Chemistry, Department of
Graduate
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d'Arcy, James Andrew. "High resolution and rapid MRI." Thesis, Institute of Cancer Research (University Of London), 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.544181.
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Goode, Ashley Harford. "High resolution ultrasonic imaging system." Thesis, University of Portsmouth, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.329278.
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Heydon, Gregory Paul. "High resolution magnetic force microscopy." Thesis, Manchester Metropolitan University, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.264716.
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Hytch, Martin J. "Quantitative high resolution electron microscopy." Thesis, University of Cambridge, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.317785.
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Aguirre, Aaron Dominic 1977. "High resolution optical coherence microscopy." Thesis, Massachusetts Institute of Technology, 2003. http://hdl.handle.net/1721.1/87341.
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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2003.Includes bibliographical references (p. 118-119).
by Aaron Dominic Aguirre.
S.M.
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Loh, Nin C. (Nin Chin) 1977. "High-resolution micromachined interferometric accelerometer." Thesis, Massachusetts Institute of Technology, 2001. http://hdl.handle.net/1721.1/89324.
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Vo, Huy Nhu. "High-resolution Optical Scanning Holography." Thesis, Virginia Tech, 2010. http://hdl.handle.net/10919/32527.
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Optical scanning holography, which was proposed by Poon[1], is a fascinating technology to record holographic information. The technique is applied in the operation of scanning holographic microscopy to record the entire three-dimensional volume of a biological specimen in the form of a hologram. With the data captured, a digital reconstruction or decoding is used to reconstruct the hologram of that such specimen. An accurate reconstruction of the recorded data provides with an in-depth analysis in the area where random noise and other imperfection effects may occur. In this thesis, three different approaches of reconstruction process are presented to provide in high-resolution a comparison between theoretical and experimental reconstruction a hologram of fluorescent beads. The first approach is to use only the experimental pinhole hologram recorded to correlate with the hologram of the object to give the reconstruction of the section. The second approach is to use the propagated pinhole hologram to reconstruct at an arbitrary depth. Finally, the third approach is to reconstruct without using the experimental pinhole hologram but with diffraction theory. Comparing these results in high-resolution gives us analysis of the reconstruction noise due to optical aberration.Master of Science
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Neufeld, Esra. "High resolution hyperthermia treatment planning." Konstanz Hartung-Gorre, 2008. http://d-nb.info/992327873/04.
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Maehigashi, Tatsuya. "Ultra-high resolution DNA crystallography." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/29684.
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Thesis (Ph.D)--Chemistry and Biochemistry, Georgia Institute of Technology, 2009.Committee Chair: Williams, Loren; Committee Member: Bottomley, Lawrence; Committee Member: Hud, Nicholas; Committee Member: Oyelere, Adegboyega; Committee Member: Wartell, Roger. Part of the SMARTech Electronic Thesis and Dissertation Collection.
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Rafik, Tahseen A. "High-resolution sonar DF system." Thesis, Loughborough University, 1992. https://dspace.lboro.ac.uk/2134/34722.
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One of the fundamental problems of sonar systems is the determination of the bearings of underwater sources/targets. The classical solution to this problem, the 'Conventional Beamformer', uses the outputs from the individual sensors of an acoustic array to form a beam which is swept across the search sector. The resolution of this method is limited by the beam width and narrowing this beam to enhance the resolution may have some practical problems, especially in low frequency sonar, because of the physical size of the array needed. During the past two decades an enormous amount of work has been done to develop new algorithms for resolution enhancements beyond that of the Conventional Beamformer. However, most of these methods have been based on computer simulations and very little has been published on the practical implementation of these algorithms. One of the main reasons for this has been the lack of hardware that can handle the relatively heavy computational load of these algorithms. However, there have been great advances in semiconductor and computer technologies in the last few years which have led to the availability of more powerful computational and storage devices. These devices have opened the door to the possibility of implementing these high-resolution Direction Finding (DF) algorithms in real sonar systems. The work presented in this thesis describes a practical implementation of some of the high-resolution DF algorithms in a simple sonar system that has been designed and built for this purpose.
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Chan, Kok Lim. "High-speed, high-resolution digital-to-analog converters." Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2007. http://wwwlib.umi.com/cr/ucsd/fullcit?p3294746.
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Thesis (Ph. D.)--University of California, San Diego, 2007.Title from first page of PDF file (viewed March 14, 2008). Available via ProQuest Digital Dissertations. Vita. Includes bibliographical references.
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Sarlo, Rodrigo. "High-Resolution, High-Frequency Modal Analysis for Instrumented Buildings." Diss., Virginia Tech, 2018. http://hdl.handle.net/10919/84477.
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Civil infrastructure failure is hard to predict, both in terms of occurrence and impact. This is due to combination of many factors, including highly variable environmental and operational conditions, complex construction and materials, and the sheer size of these structures. Often, the mitigation strategy is visual inspection and regular maintenance, which can be time-consuming and may not address root causes of failure. One potential solution to anticipating infrastructure failure and mitigating its consequences is the use of distributed sensors to monitor the physical state of a structure, an area of research known commonly as structural health monitoring, or SHM. This approach can be applied in a variety of contexts: safety during and after natural disasters, evaluation of building construction quality and life-cycle assessment for performance based design frameworks.
In one way or another, SHM methods always require a ``baseline,'' a set of physical features which describes the behavior of a healthy structure. Often, the baseline is defined in terms of modal parameters: natural frequencies, damping ratios, and mode shapes. Although changes in modal parameters are indicative of structural damage, they are also indicative of a slew of non-damage factors, such as signal-to-noise ratio, environmental conditions, and the characteristics of forces exciting the structure. In many cases, the degree of observed modal parameter changes due to non-damage factors can be much greater than that due to damage itself. This is especially true of low-frequency modal parameters. For example, the fundamental frequency of a building is more sensitive to global influences like temperature than local structural changes like a cracked column.
It has been proposed that extracting modal parameters at higher frequencies may be the key to improving the damage-sensitivity of SHM methods. However, for now, modal analysis of civil structures has been limited to low frequency ambient excitation and sparse sensor networks, due to practical limitations. Two key components for high-frequency modal analysis have yet to be studied: 1) Sufficient excitation at high frequencies and 2) high-resolution (high sensor density) measurements. The unifying goal of this work is to expand modal analysis in these two areas by applying novel instrumentation and experimental methods to two full-scale buildings, Goodwin Hall and Ernest Cockrell Jr. Hall. This enables realistic, practical insights into the limitations and benefits of the high-frequency SHM approach. Throughout, analyses are supported through the novel integration of uncertainty quantification techniques which so far has been under-utilized in the field.
This work is divided into three experimental areas, with approaches centering on the identification of modal parameters. The first area is the application of high spacial resolution sensor networks in combination to ambient vibration testing. The second is the implementation of a robust automation and monitoring strategy for complex dynamic structures. The third is the testing of a novel method for performing experimental modal analysis on buildings emph{in situ}. The combination of results from these experiments emphasizes key challenges in establishing reliable high-frequency, high-resolution modal parameter ``baselines'' for structural health monitoring (SHM) of civil infrastructure.
The first study presented in this work involved the identification of modal parameters from a five-story building, Goodwin Hall, using operational modal analysis (OMA) on ambient vibration data. The analysis began with a high spacial density network of 98 accelerometers, later expanding this number to 117. A second extensional study then used this data as reference to implement a novel automation method, enabling the identification of long-term patterns in the building's response behavior. Three dominant sources of ambient excitation were identified for Goodwin Hall: wind, human-induced loading, and consistent low-level vibrations from machinery, etc. It was observed that the amplitude of excitation, regardless of source, had significant effects on the estimated natural frequencies and damping ratios. Namely, increased excitation translated to lower natural frequencies and higher damping. In addition, the sources had different characteristics in terms of excitation direction and bandwidth, which contributed to significantly different results depending on the ambient excitation employed. This has significant implications for ambient-based methods that assume that all ambient vibrations are broadband random noise.
The third and final study demonstrated the viability of emph{in situ} seismic testing for controlled excitation of full-scale civil structures, also known as experimental modal analysis (EMA). The study was performed by exciting Ernest Cockrell Jr. Hall in Austin, Texas with both vertical and lateral ground waves from seismic shaker truck, T-Rex. The EMA results were compared to a standard operational modal analysis (OMA) procedure which relies on passive ambient vibrations. The study focused on a frequency bandwidth from 0 to 11 Hz, which was deemed high frequency for such a massive structure. In cases were coherence was good, the confidence comparable or better than OMA, with the added advantage that the EMA tests took only a fraction of the time. The ability to control excitation direction in EMA enabled the identification of new structural information that was not observed OMA. It is proposed that the combination of high spacial resolution instrumentation and emph{in situ} excitation have the potential to achieve reliable high-frequency characterization, which are not only more sensitive to local damage but also, in some cases, less sensitive to variations in the excitation conditions.Ph. D.
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Welter, Joseph Donald. "NPS high resolution synthetic aperture sonar." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1995. http://handle.dtic.mil/100.2/ADA306558.
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Thesis (M.S. in Applied Physics and M.S. in Electrical Engineering) Naval Postgraduate School, December 1995."December 1995." Thesis advisor(s): Donald L. Walters, Roberto Cristi. Bibliography: p. 101. Also available online.
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Murphy, Brandee L. "A high resolution satellite communications model." Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1997. http://handle.dtic.mil/100.2/ADA341533.
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Thesis (M.S. in Operations Research) Naval Postgraduate School, September 1997."Deptember 1997." Thesis advisor(s): Samuel H. Parry. Includes bibliographical references (p. 119). Also available online.
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Ernst, Herbert. "High resolution thermal measurements in fluids." [S.l. : s.n.], 2001. http://deposit.ddb.de/cgi-bin/dokserv?idn=963763555.
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Schütz, Oliver. "High-resolution studies of protoplanetary disks." [S.l. : s.n.], 2005. http://deposit.ddb.de/cgi-bin/dokserv?idn=974449792.
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Christerson, Linus. "High Resolution Genotyping of Chlamydia trachomatis." Doctoral thesis, Uppsala universitet, Klinisk bakteriologi, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-156751.
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Chlamydia trachomatis is an obligate intracellular bacterium of major human health concern, causing urogential chlamydia infections, lymphogranuloma venereum (LGV) and trachoma. Chlamydia is one of the most common sexually transmitted infections worldwide and can cause infertility. In the first four papers described herein we used a high resolution multilocus sequence typing (MLST) system to investigate the epidemiology of C. trachomatis, and showed that MLST is superior to conventional ompA genotyping with respect to resolution. In the fifth paper we simplified the methodology by developing and validating a multilocus typing (MLT) DNA microarray based on the MLST system. In more detail, MLST analysis of consecutive specimens from 2006 in Örebro County in Sweden, and comparison to specimens from 1999-2000, showed that the new variant C. trachomatis (nvCT) is monoclonal and likely has appeared in recent years. MLST analysis of LGV specimens from men who have sex with men (MSM) showed that the increase of LGV in Europe in the last decade indeed was a clonal outbreak, contrary to the USA where LGV might have been present all along. In the third paper, clinical symptoms could not be correlated with the MLST genotypes, suggesting, together with the combined results of all previous studies, that bacterial factors, if important, need to be understood in the context of host factors. MLST analysis of specimens from a high incidence C. trachomatis area in North Norway revealed interesting epidemiological details concerning unusual genetic variants, the nvCT and MSM, but found no significant difference in genetic diversity compared to two other geographic areas in Norway. Lastly, we developed a MLT array that provides high resolution while being rapid and cost-effective, which makes it an interesting alternative for C. trachomatis genotyping. In conclusion, the MLST system and the MLT array have proven to be useful tools and should now be applied in further investigations to improve our understanding of C. trachomatis epidemiology.
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Vlassenbroek, Alain. "Radiation damping in High Resolution NMR." Doctoral thesis, Universite Libre de Bruxelles, 1993. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/212811.
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Woodward, D. R. "High resolution spectroscopy of transient species." Thesis, University of Oxford, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.376972.
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Hayman, G. D. "High resolution spectroscopy of molecular beams." Thesis, University of Oxford, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.371513.
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Sanchez, Panchuelo Rosa Maria. "High resolution anatomical and functional imaging." Thesis, University of Nottingham, 2009. http://eprints.nottingham.ac.uk/10908/.
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The signal-to-noise ratio available in Magnetic Resonance Imaging (MRI)is determined by the static magnetic field strength, causing a continued drive toward higher fields to enable faster image acquisition at finer spatial resolution. The work in this thesis is primarily concerned with the development of sequences for Ultra High Field Magnetic Resonance Imaging (7T) which allow the acquisition of images with high spatial resolution for study of the structure and function of the brain. The methods developed here for high spatial resolution structural imaging allow the identification of regions of the cortex which exhibit layers of high myelin concentration within the cortical strip. This permits the investigation of the correspondence of functional regions in the visual cortex to their underlying structure 'in vivo'. A robust methodology for high resolution functional mapping over a restricted field of view is presented and the results of fMRI studies demonstrating 1 mm isotropic resolution in the primary somatosensory cortex S1 using this methodology are shown. BOLD responses to vibrotactile digit stimulation were investigated using a travelling wave paradigm to measure the topographic representation of the digits in S1 and an event related paradigm for characterization of the haemodynamic delay. A spin-echo EPI acquisition has been optimized and tested to compare the BOLD response in GE and SE echo planar images by employing visual and motor tasks. The specificity of the BOLD responses of SE and GE data was found to be similar using a travelling wave paradigm.
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Enos, C. S. "Applications of high-resolution translational spectroscopy." Thesis, Swansea University, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.636906.
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In 1927, E.P. Wigner proposed that in the event of weak spin-orbit coupling the only spectroscopic processes likely to occur were those for which the total electron spin angular momentum was conserved, namely ΔS = 0. This later became known as the Wigner Spin Conservation Rule. Its implications for radiative processes have been extensively investigated and it is now known that they adhere closely to the ΔS = 0 selection rule. In contrast, the application of the spin rule to binary collisional processes has been the subject of a small number of studies from which only tentative conclusions could be drawn as to its validity. To redress this imbalance, a systematic investigation was undertaken by the author for ion (keV)-particle (thermal) collisions, the results of which are presented in this thesis. In total, 164 reaction channels were identified of which the overwhelming majority (158) were found to be spin conservative. Furthermore, a modified version of the ΔS = 0 selection rule is proposed which states that if one collision partner undergoes a transition involving a multiplicity change a simultaneous transition in the other partner must conform to the selection rule ΔS = 0 or 1 with the proviso that singlet-singlet transitions are forbidden. During a charge stripping investigation of 4keV B^+,C^+ and Ar^+ ions, several features observed in the spectra using non-singlet target particles such as O_2 and NO, were not present when singlet target particles such as N_2 and Ne were used. To explain these discrepancies, a novel pseudo two step mechanism is proposed in which the ion undergoes a rearrangement stage prior to explusion of the electron. Metastable ions substantially influence collisional processes and to facilitate the former investigations, the fractional metastable content of six atomic ion beams (B^+, C^+, N^+, O^+, F^+ and Cl^+) formed by Electron Ionization are quantified.
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Collier, A. P. "High resolution imaging of crystalline agglomerates." Thesis, University of Cambridge, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.597853.
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A novel method of forming pure calcite seed materials by nucleation from an alkaline solution was developed. Batch experiments were conducted to investigate the growth and agglomeration rates of the calcite seed particles under varying agitation rates. Stirrer speeds between 700 and 2000 rpm were studied. The experiments were all carried out in a saline solution of ionic strength 0.153 M, with an initial supersaturation of approximately 4.0. The data from the experiments were analysed using the program Batch (Hounslow, 1990). This program extracts growth and agglomeration rates from the changes observed in particle size distributions with time. It is found that the growth rate is independent of the crystal size and the agitation rate. Growth rates from all experiments can be expressed by a single equation with a second order dependence of the growth rate on the supersaturation. This dependence, and the magnitude of the growth rate constant are consistent with other reports in the literature. The agglomeration rate is best described by a size-independent agglomeration kernel. At all except the lowest stirrer speed, the agglomeration rate is found to be proportional to the growth rate. The agglomeration rate is found to decrease as the stirrer speed increases. Correlation of the agglomeration rate with the stirrer speed shows that the agglomeration rate is proportional to the stirrer speed raised to the (-1.5) power. A comparison with estimates for the average shear rate within a stirred vessel suggest that the agglomeration rate is inversely proportional to the average shear rate within the crystalliser. Microscopic examination of many calcite samples was undertaken with SEM systems. Several hundred images of calcium carbonate particles were obtained. High resolution images were used to identify the phases present in preliminary trials, and to confirm that the calcite was the main product of the batch growth experiments. Images of samples taken from the batch growth experiments were used to confirm the decrease in the agglomeration rate at higher stirrer speeds, and the constancy of the growth rate. No evidence was found for any preferential alignment of the crystallites within the agglomerates produced by this method.
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Wassall, Richard David. "High resolution studies of sympathetic neurotransmission." Thesis, University of Oxford, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.497141.
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McLaren, S. "High-resolution ultrasonic non-destructive testing." Thesis, City University London, 1987. http://openaccess.city.ac.uk/8335/.
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The use of ultra-short pulse wideband ultrasonic transducers in Non-Destructive-Testing (NDT) has been investigated both theoretically and experimentally. It is demonstrated that the resolution of pulse-echo NDT is affected by diffraction effects which also complicate the interpretation of echo signals. These diffraction effects are interpreted in terms of the plane- and edge-wave model of *transducer fields. Improverents can be obtained by the use of non-uniformly excited transducers of two basic types: the first, the plane-wave-only (PWO) source; is more strongly excited at its centre than towards the rim, where the excitation is gradually reduced to zero in order to remove the edge wave. The second type, an edge-wave-only (EWO) source, is more strongly excited at its rim than in the centre, thereby effectively removing the plane wave. Computer modelling of pressure waveforms in the field of PWO and EWO sources has been carried out using an extension to the impulse response method. Experimental point-pressure waveform measurements in the field of a prototype EWO transducer, made using a miniature ultrasonic probei are in reasonable agreement with the calculated results. Detailed calculations are made of the transmit-receive mode (pulse-echo) responses arising from solid targets of various size in a flu- id medium interrogated by uniformly and non-uniformly excited sources. The theoretically predicted results are in good agreement with experimentally measured results obtained using a conventional transducer and an equivalent prototype EWO transducer. The effects of target size, field position and material on both the amplitude and shape of the echo responses are investigated. The structure of the responses is explained in terms of the plane and edge waves radiated by the source. Implications for the use of techniques to both size (Distance, Gain, Size curves) and characterise (ultrasonic spectroscopy) defects are examined. The applications of new, nonuniformly excited transducers in high-resolution NDT and ultrasonic imaging are evaluated.
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梁韻詩 and Wan-sze Leung. "High resolution spectroscopy of free radicals." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1998. http://hub.hku.hk/bib/B31237319.
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Xia, Ye, and 夏晔. "High resolution spectroscopy of scandium monohalides." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2012. http://hub.hku.hk/bib/B49617886.
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This thesis reports the study of the molecular and electronic structure of scandium monohalides using the technique of laser ablation/reaction with supersonic free jet expansion used for producing the target molecules and laser induced fluorescence (LIF) spectroscopy for recording their electronic transition spectrum. The scandium diatomic molecules studied in this work were scandium monoiodide (ScI) and scandium monobromide (ScBr), which were produced by the reaction of Sc atoms with 2% CH3I and 2% C2H5Br gases seeded in Ar carrier gas, respectively. The LIF spectrum of the electronic transition of ScI and ScBr were recorded in the visible and near infrared spectral region between 613 and 854 nm. The analysis of the high resolution electronic spectra of ScI and ScBr yielded molecular constants and information of electronic structures. For all the transition bands observed, rotationally-resolved transition lines were fit to a theoretical model to retrieve molecular constants for both upper and lower electronic states.
For the ScI molecule, seven vibrational bands of the D1П –X^1 Σ^+ system were recorded and analyzed. Accurate molecular constants for the v = 0 – 2 levels of the D^1П state and the v = 0 – 3 levels of the X^1 Σ^+ state were obtained. The equilibrium bond lengths, re (Å), for the electronic states of ScI were determined as follows:
ScI X^1 Σ^+ D^1П
r_e(Å) 2.6078 2.7146
For the ScBr molecule, three electronic transition systems were recorded and analyzed, which include six vibrational bands of the C^1 Σ^+– X^1 Σ^+ system, seven vibrational bands of the e^3Δ–a^3Δsystem and two vibrational bands of the d3Φ – a3Δ system. Rotationally resolved transition lines of both Sc79Br and Sc81Br isotopes were observed and analyzed. Least-squares fitting of the measured line positions yielded accurate molecular constants for the v = 0 – 2 levels of the X^1 Σ^+ state, the v = 0 – 3 levels of the C^1 Σ^+ state, the v = 0 and 1 levels of the d3Φ state and the v = 0 – 2 levels of both e3Δ and a3Δ states, respectively. The equilibrium bond lengths, re (Å), determined for electronic states of ScBr are given as follows:
ScBr X^1 Σ^+ a^3Δ C^1 Σ^+
r_e(Å) 2.3806 2.4767 2.4776
A molecular orbital (MO) energy level diagram has been used to examine the electronic configurations giving rise to the different observed electronic states of ScI and ScBr. An attempt has been made to put the MOs of all the scandium monohalides under a single picture. A comparison of the molecular constants for the different electronic states of scandium monohalides indicates a weakening of the chemical bonding between the scandium atom and the halogen atoms down the group.published_or_final_version
Chemistry
Doctoral
Doctor of Philosophy
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Breden, William Olin, and James Jeffrey Zanoli. "Visualization of high-resolution digital terrain." Thesis, Monterey, California. Naval Postgraduate School, 1989. http://hdl.handle.net/10945/27333.
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Atrill, Stefan Roger. "High resolution photofragmentation of cluster ions." Thesis, University of Sussex, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.320362.
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HERRERA, LUIS ERNESTO YNOQUIO. "HIGH RESOLUTION PHOTON COUNTING OPTICAL REFLECTOMETRY." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2015. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=27673@1.
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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIROCOORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR
FUNDAÇÃO DE APOIO À PESQUISA DO ESTADO DO RIO DE JANEIRO
PROGRAMA DE EXCELENCIA ACADEMICA
BOLSA NOTA 10
Neste trabalho são apresentados dois reflectômetros ópticos por contagem de fótons no domínio do tempo para o monitoramento de fibras ópticas. O primeiro foi projetado para obter faixas dinâmicas altas. Demonstrou-se a sua capacidade de sintonização no monitoramento de redes passivas WDM-PON durante o tráfego de dados. 32 dB de faixa dinâmica com 6 m de resolução foram atingidos. O segundo reflectômetro foi projetado para atingir resoluções ultra altas. As aplicações neste caso, além do monitoramento de uma rede TDM-PON de curto alcance, foram na caracterização de redes de Bragg dispersivas e na descrição e modelagem de um fenômeno não reportado antes na literatura, chamado nesta tese de reflexão por curvatura. Foi demonstrada uma resolução menor que 3 cm com faixa dinâmica maior que 14.0 dB.
This thesis presents the development of two photon counting optical time domain reflectometers for fiber optic links monitoring. The first one was focused on high dynamic range. It is demonstrated its tunable capability for a WDM-PON in-service monitoring. 32 dB on dynamic range and a two-point resolution of 6 m is achieved. The second reflectometer was design to accomplish an ultra high resolution. The monitoring of a short TDM-PON is performed. Moreover, due to its high resolution, a chirped fiber Bragg grating is characterized and a non previous reported phenomena, the bend reflection, is shaped and described. It is demonstrated 3 cm two-point resolution and more than 14 dB on dynamic range.
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Park, Dongwook 1959. "High-resolution laser radar performance analysis." Thesis, Massachusetts Institute of Technology, 1988. http://hdl.handle.net/1721.1/14712.
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Speaks, Rachel Suzanne. "High-resolution pattern transfer for nanofabrication." Thesis, University of Cambridge, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.616072.
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Humpherys, Brian. "SIGNAL TDOA BASED HIGH RESOLUTION TSPI." International Foundation for Telemetering, 1994. http://hdl.handle.net/10150/608843.
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International Telemetering Conference Proceedings / October 17-20, 1994 / Town & Country Hotel and Conference Center, San Diego, CaliforniaThis paper describes a method for determining high resolution time, space, and position information for a test range flight vehicle using four tracking receivers. Equipped with GPS time systems, each receiver records the exact time at which a time marker embedded in the transmitted TM data stream is received. With this information, the time difference of arrival for the time markers at three of the receivers can be calculated referenced to the fourth. Using this time difference, the position of the transmitter can be determined. The accuracy with which the received signal time delay can be calculated depends on the accuracy of the GPS time system at each receiver. The effect of time accuracy on positional resolution is evaluated.
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Coetzee, Shirley Lynne. "Narrow band high resolution radar imaging." Thesis, University College London (University of London), 2007. http://discovery.ucl.ac.uk/1445216/.
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Most modern radar systems use a monostatic configuration and exploit wide bandwidth to achieve high down range resolution used for target detection and classification. However increasing pressure on occupancy of the radio spectrum and the requirement for ever more accurate target classification poses serious challenges to future radar designs. Techniques based on narrow band radar are thus being investigated as a mean of reducing spectral occupancy. This approach can be coupled with the use of a multiple radar (multistatic) geometry to provide a potentially powerful technique for improving target detection and classification even beyond that of conventional systems. A multistatic topography allows the application of tomographic techniques for target imaging. Tomography is a process by which a two-dimensional cross-sectional image of an object is obtained via illumination from a variety of differing angles in a variety of differing planes. In radar tomography observations from multiple radar locations enable a three dimensional projection in Fourier space. In this way a three dimensional image of an object can be constructed using techniques such as Backprojection. The use of a narrow band waveform in multistatic radar tomography trades resolution achieved by bandwidth for resolution achieved by spatially diverse angular imaging. This thesis reports a detailed investigation into a range of narrow band, multistatic geometries and techniques to obtain high resolution imaging of moving targets. Images processed using Synthetic Aperture Radar (SAR) and Inverse SAR (ISAR) configurations, modified to emulate multistatic narrow band configurations, have been investigated for both real and simulated data. The effect on the spatial resolution due to masking, ambiguity and coherency of targets consisting of both sparse and dense scatterers was analysed under a range of conditions. A cross range resolution of A/4 was achieved using simulated data. This analysis was also extended to the case of real data of typical ground targets. In this situation the data is inevitably significantly affected by noise but a resolution of A/2 was achieved. This study concludes with a comparison of modeled narrow band system performance with theoretical predictions leading to a preliminary assessment of the capability of the narrow band radar tomographic imaging technique for potential applications.
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Surampudi, Bala Anjani Vasudha. "High-Resolution Modeling of Steel Structures." University of Cincinnati / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1504787210175847.
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Bas, Alon. "An ultra high resolution FMCW radar." Master's thesis, University of Cape Town, 1992. http://hdl.handle.net/11427/8357.
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Bibliography: leaves 127-128.There is a great need for real-time non-intrusive measurements in industry. A short-range radar system can be used to make these measurements. A standard requirement for these type of applications is high resolution. This is a standard problem in radar. Using classical signal processing techniques, the range resolution is proportional to the bandwidth of the transmitted signal. This poses a serious problem in radar as very large bandwidths are required - typically lSOGHz for 1 mm range resolution. Alternative techniques have been sought which do not rely on large transmitted bandwidths, but which rely on large signal-to-noise ratio (SNR). Such techniques exist in modem spectral analysis eg. auto-regressive techniques. These techniques model the data. In other words, they assume a priori information. Linear frequency-modulated continuous-wave (FMCW) radar was utilized, since a pulsed radar would require very precise time measurements due to the short range (a few ns). The FMCW radar would have to be very linear for the modelling process to work properly. The frequency domain measurement of the received system data would then be proportional to range. An FMCW radar system was built and tested. The modem signal processing techniques were found to work well when injected with sinusoidal signals from signal generators. The hardware was also found to perform satisfactorily. However, amplitude modulation was observed in the mixing process and subsequently, the modelling process did not perform satisfactorily when interfaced to the hardware. Due to the amplitude modulation problem, two closely-spaced targets disrupted the high resolution properties of the modelling process. Nevertheless, a single target could be resolved within a resolution bin of better than 1 cm. A solution is proposed in chapter eight, however, it is out of the scope of this thesis.
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Hubbard, Alun Lloyd. "High resolution modelling of glacier flow." Thesis, University of Edinburgh, 1998. http://hdl.handle.net/1842/20582.
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