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Rodrigues, Lidiany Karla Azevedo. „O uso do laser de CO2 na prevenção da carie dentaria“. [s.n.], 2005. http://repositorio.unicamp.br/jspui/handle/REPOSIP/288097.
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Orientador: Marines Nobre dos Santos UchoaTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba
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Resumo: A irradiação do esmalte dental com laser de CO2, especialmente se associada ao flúor, aumenta a resistência deste substrato ao desafio ácido. Deste modo, esta tese, constituída por 3 artigos, teve por objetivos: (1) descrever as características do laser de CO2 e revisar a literatura disponível enfocando seus efeitos na prevenção de cárie em esmalte e dentina, bem como discutir os efeitos deste mesmo laser quando associado ao flúor; (2) investigar, in vitro, o efeito do laser de CO2 (? = 10,6 µm), com duas densidades de energia, na inibição da desmineralização ao redor de restaurações de resina composta; (3) avaliar in situ os efeitos combinados de um TEA (Transversely Excited Atmospheric-pressure) laser de CO2 (? = 9,6 µm) e do dentifrício fluoretado na desmineralização do esmalte dental humano. No estudo 1, a literatura científica pertinente ao assunto foi pesquisada usando a base de dados medline e busca manual de referências citadas em artigos científicos. No estudo 2, preparos cavitários realizados com ponta diamantada em esmalte hígido tiveram seu ângulo cavo-superficial irradiado com laser de CO2 com 8 ou 16 J/cm2. Através de microdureza em corte longitudinal, avaliou-se a perda mineral in vitro dos grupos experimentais e controle no esmalte ao redor da restauração. No estudo 3, foi testado in situ o efeito do laser de CO2 com 1,5 J/cm2 associado ou não à utilização de dentifrício fluoretado na prevenção de cárie dentária. Avaliou-se a perda mineral do esmalte dental humano nos grupos experimentais e controle. Os resultados dos estudos 2 e 3 foram analisados estatisticamente pelos testes ANOVA e Tukey com nível de significância fixado em 5%. A análise da literatura apresentada no artigo 1 mostrou que pode haver um futuro promissor para o laser de CO2 na prevenção de cárie dentária tendo seu efeito preventivo potencializado quando utilizado em associação a compostos fluoretados. Os resultados do artigo 2 demonstraram que o laser utilizado foi efetivo na inibição da desmineralização do esmalte ao redor de restaurações de resina composta (p < 0,05) e que o aumento da energia não potencializou o efeito do laser. No terceiro estudo, observou-se que os tratamentos com laser e/ou dentifrício fluoretado foram capazes de inibir a desmineralização do esmalte in situ, tendo sido observado o melhor resultado de inibição da desmineralização quando o laser foi associado à utilização de dentifrício fluoretado. Em conclusão, os resultados desses estudos indicam que o laser de CO2 é capaz de inibir a desmineralização do esmalte dental humano em situações de alto desafio cariogênico in vitro e in situ, apresentando efeito sinérgico quando associado ao flúor
Abstract: The irradiation of dental enamel by CO2 laser, especially if combined with fluoride, increases the enamel acid resistance. Thus, this thesis, comprised by 3 manuscripts, aimed: (1) to describe the characteristics of the CO2 laser and to review the literature with regard to its effects on caries inhibition in enamel and dentin. Another aim of this review is to discuss the effects of the CO2 laser in combination with fluoride; (2) to investigate, in vitro, the effect of a carbon dioxide laser (? = 10.6 µm), with two energy densities, on the enamel inhibition of demineralization around composite restorations; (3) to assess in situ the combined effects of a 9.6 µm TEA (Transversely Excited Atmospheric-pressure) CO2 laser and fluoride dentifrice on the demineralization of human dental enamel. In study 1, the scientific literature related to the issue was searched using medline and manual tracing of references cited scientific papers. In study 2, cavity preparations performed with diamond bur on sound enamel had their cavo surface angle irradiated with CO2 laser using 8 or 16 J/cm2. In vitro mineral loss, in experimental and control groups, was evaluated in the enamel around the restoration. In manuscript 3, the in situ caries preventive effect of the CO2 laser, with 1.5 J/cm2, associated or not to fluoridated dentifrice, was tested. In the human dental enamel, mineral loss was evaluated, by cross-sectional microhardness, in experimental and control groups. The results of studies 2 and 3 were analyzed by ANOVA and Tukey test. The literature analysis presented in study 1 showed that there can be a promising future for CO2 laser in caries prevention and its preventive effect is improved when associated to fluoride products. The results of study 2 demonstrated that the laser used was effective in inhibiting enamel demineralization around the composite restorations (p < 0.05). In the third manuscript, it was observed that the treatments with laser and/or fluoridated dentifrice were able to inhibit the in situ enamel demineralization and the best demineralization inhibition result was observed when laser was combined with fluoridated dentifrice use. In conclusion, the results of these studies suggest that CO2 laser is able of inhibiting enamel demineralization, in in vitro and in situ high cariogenic challenge situations, showing synergic effect with fluoride
Doutorado
Cariologia
Doutor em Odontologia
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Penk, David. „Vyhotovení 3D modelu části budovy SPŠ stavební Brno“. Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2021. http://www.nusl.cz/ntk/nusl-444256.
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The thesis deals with the creation of a 3D model from data collected by laser scanning. The first part deals with the theoretical foundations of buildings information modeling and method of laser scanning. The rest of the work describes the detailed process from data collection to the creation of the model. Most of the space is devoted to work in the Revit software environment.
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Pan, Jingyi. „Confocal scanning laser tomography and scanning laser Doppler flowmetery in the rat eye“. Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ49422.pdf.
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Svedberger, Johan, und Jonas Andersson. „Laser scanning in manufacturing industries : The potential and usability of laser scanning for industrial applications“. Thesis, KTH, Industriell produktion, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-134954.
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Making mistakes or discovering errors too late in the factory layout process is very costly. Unfortunately, the layouts aren’t always accurate or updated which creates a degree of uncertainty when it comes to installation of new equipment and rebuilding facilities. It also leads to a lot of waste in movement when employees has to go out in production to perform measurements, take pictures and take notes in order to remember important details to avoid errors. Lasers in land and engineering surveying instruments have been widely used for the last 30 years. A natural development has been to add a scanning mechanism to a total station that were already equipped with laser rangefinders and angular encoders, allowing automated measurement and location of thousands of nonspecific points. The automobile industry has begun to see the potential of laser scanning, mainly because of the development of the software handling the scan results, the point clouds. Scania, in collaboration with the FFI research project at the Royal Institute of Technology (KTH), therefore wanted to investigate how the new possibilities of 3D laser scanning can facilitate the development and maintenance of production systems and how it could be implemented in the current factory design process. By scanning three locations at Scania related to machining, assembly and aftermarket service the usability of the results has been investigated with the software Faro Scene and Bentley Pointools V8i. The results of the study showed that the laser scanning technology can generate several possibilities for manufacturing industries. The technology can be profitable and the modern point cloud software and applications could support the work of the layout design process greatly. Three main application areasfound: Visualization & communication: The point cloud is an excellent information carrier and can easily be used as a visualization aid for meetings or simply to refreshing memories of a location. It also provides the possibility to view and examine a location remotely. Gather information: The measuring possibilities are immense, allowing single point and distance measurements without the concern of interfering with objects. The method can to some extent replace the current approach in measuring buildings and floor flatness. Simulation & verification: Software can perform advanced simulations and verifications of existing and future layouts, models and installations. Parts of the point cloud can be colorized, hidden, removed, duplicated or transformed. Existing 2D layout drawings or 3D models can be attached and verified relative the point cloud. The attached objects can be simulated with clash collision or differencing. Keywords: 3D Laser Scanning, TLS, CAD, Point Cloud, Factory Layout, Faro Scene, Bentley Pointools V8i, FactoryDesign Process, Factory Scanning Process.
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Shinpaugh, Kevin A. „Measurements in the bimodal region of a wing-body junction flow with a rapidly-scanning two-velocity-component laser-Doppler velocimeter“. Diss., This resource online, 1994. http://scholar.lib.vt.edu/theses/available/etd-06062008-163435/.
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葉社榮 und Sair-wing Yip. „Discontinuity survey using laser scanning technology“. Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2003. http://hub.hku.hk/bib/B30431670.
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Maillaud, Fabrice Franck Maurice. „Performance enhancement of laser scanning displays“. Thesis, University of the West of England, Bristol, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.311879.
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Sexton, Cornelius Leo. „Rapid Alloy Scanning by laser cladding“. Thesis, University of Liverpool, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.320605.
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Chen, Kenwei. „Intelligent scanning in selective laser sintering /“. Digital version accessible at:, 1998. http://wwwlib.umi.com/cr/utexas/main.
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Townsend, Russell James. „Experimental study of a scanning laser doppler flowmeter“. University of Western Australia. Centre for Ophthalmology and Visual Science, 2005. http://theses.library.uwa.edu.au/adt-WU2005.0063.
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[Truncated abstract] Purpose: To improve our ability to interpret and validate Heidelberg Retina Flowmeter (HRF) flow images by recording flow measurements from specific regions of the retinal vasculature in in-vitro and in-vivo eye models in which retinal blood flow can be manipulated. Methods: The first experiments utilised an isolated perfused pig eyes perfused with a 50%/50% Krebs/RBC solution at known flow rates ranging from zero to 300 μl/min. After HRF image acquisition, the retinal vasculature was perfused with fluorescein isothiocyanate (FITC), for fluorescence microscopy. Using the standard HRF software and a 10×10 pixel measurement window, flow rates were measured from a retinal artery, vein, arteriole, venule, and the retinal capillary bed and a capillary-free-zone. The relationship between HRF measured flow and perfusion flow in the different measurement regions was determined. For the second study, HRF flow images were acquired at retinal sites in Brown Norway rats over a range of focus levels before and after cessation of retinal blood flow by laser-induced central retinal artery occlusion. Using the 10×10 pixel and 4×4 pixel measurement windows, HRF measured flow was performed in retinal artery, vein, arteriole, capillary and choroidal vessel locations. The relationship between HRF measured flow and focus depth was determined for each location before and after central retinal artery occlusion. At the conclusion of each experiment the effect of reduction of systemic blood pressure (by exsanguination) on HRF flow measurements in choroidal vessels and in locations without visible choroidal vessels was assessed. Finally, HRF flow measurements were acquired after euthanasia, to determine the HRF flow signal which was still present under zero biological flow conditions (the zerooffset). Results: In the isolated perfused pig eye experiments it was found that the HRF flow response varied according to vascular location. At zero perfusate flow, HRF flow was consistently greater than zero at all locations, averaging 171.9 ± 44.7 AU (n=97), representing background noise. Arteries and veins yielded the highest HRF measured flow values, but the relationship between HRF measured flow and perfusate flow was not linear. In arterioles the HRF flow was more linear over a broader range of perfusate flow rates but the peak flow signal was an order of magnitude smaller than that in arteries and veins. Both the linearity and magnitude of the flow signal in venules was less than that in arterioles.
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ALMEIDA, IVAN A. de. „Otimização do processo de usinagem de titânio com laser pulsado de neodímio“. reponame:Repositório Institucional do IPEN, 2007. http://repositorio.ipen.br:8080/xmlui/handle/123456789/11589.
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Tese (Doutoramento)
IPEN/T
Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP
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Drake, Devin Robert. „Applications of laser scanning and imaging systems“. [Gainesville, Fla.] : University of Florida, 2002. http://purl.fcla.edu/fcla/etd/UFE0000526.
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Gattuso, Luca. „Monitoraggio di una frana tramite Laser Scanning“. Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2011. http://amslaurea.unibo.it/2502/.
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Filbrandt, Philip W. M. „The characterisation of a scanning laser microscope“. Thesis, University of Manchester, 1996. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.755293.
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Pankajakshan, Praveen. „Blind deconvolution for confocal laser scanning microscopy“. Nice, 2009. http://www.theses.fr/2009NICE4057.
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La microscopie confocale à balayage laser est une technique puissante pour étudier les spécimens biologiques en trois dimensions (3D) par sectionnement optique. Bien qu’ubiquitaire, il persiste des incertitudes dans le procédé d’observations. Comme la réponse du système à l’impulsion, ou fonction de flou (PSF), est dépendante à la fois du spécimen et des conditions d’acquisition, elle devrait être estimée à partir des images observées avec l’objet. Ce problème est mal posé, sous déterminé, et comme le processus de mesure est quasi-aléatoire dans la nature, nous le traitons en utilisant l’interférence bayésienne. L’état de l’art des algorithmes concernant la déconvolution et déconvolution aveugle est exposé dans le cadre d’un travail bayésien. Dans la première partie, nous constatons que la diffraction limitée de l’objectif et le bruit intrinsèque, sont les distorsions primordiales qui affectent les images d’un spécimen fin. Une approche de minimalisation alternative (AM), restaure les fréquences manquantes au-delà de la limite de diffraction, en utilisant une régularisation de la variation totale sur l’objet, et une contrainte spatiale sur la PSF. En outre, des méthodes sont proposées pour assurer la positivité des intensités estimées, conserver le flux de l’objet, et bien manier le paramètre de la régularisation. Quand il s’agit d’imager des spécimens épais, la phase de la fonction de la pupille, due à l’aberration sphérique (SA) ne peut être ignorée. Dans la seconde partie, il est montré qu’elle dépend de la discordance de l’index de réfraction entre l’objet et le milieu d’immersion de l’objectif et de la profondeur sur la lamelle. Les paramètres d’imagerie et la distribution de l’intensité originelle de l’objet sont récupérés en modifiant les algorithmes AM. Due à l’incohérence de la microscopie à fluorescence, la phase de récupération des intensités observées est possible en contraignant la phase par l’utilisation d’optiques géométriques. Cette méthode pourrait être étendue pour restituer des spécimens affectés par la SA. Comme la PSF varie dans l’espace, un modèle de quasi-convolution est proposé, et la PSF est rendue approximative. Ainsi, en plus de l’objet, il suffit d’estimer un seul libre paramètreConfocal laser scanning microscopy is a powerful technique for studying biological specimens in three dimensions (3D) by optical sectioning. Although ubiquitous, there are uncertainties in the observation process. As the system’s impulse response or point-spread function (PSF) is dependent on both the specimen and imaging conditions, it should be estimated from the observed images along with the object. This problem is ill-posed, under-determined, and as the measurement process is quasi-random in nature, we treat the problem by using Bayesian inference. The state of the art déconvolution and blind déconvolution algorithms are reviewed within a Bayesian framework. In the first part, we recognize that the diffraction-limited nature of the objective lens and the intrinsic noise are the primary distortions that affect this specimen images. An alternative minimization (AM) approach restores the lost frequencies beyond the diffraction limit by using a total variation regularization on the objet, and a spatial constraint on the PSF. Additionally, some methods are proposed to ensure positivity of estimated intensities, conserve the object’s flux, and to handle the regularization parameter. When imaging thick specimens, the phase of the pupil function due to spherical aberration (SA) cannot be ignored; It is shown to be dependent on the refractive index mismatch between the object and the objective immersion medium, and the depth under the cover slip. The imaging parameters and the object’s original intensity distribution is recovered by modifying the AM algorithm. Due to the incoherent nature of fluorescence microscopy, phase retrieval from the observed intensities is possible by constraining the phase using geometrical optics. This method could be extended to restore specimens affected by SA. As the PSF is space varying, a quasi-convolution model is proposed, and the PSF approximated so that, apart from the object, there is only one free parameter to be estimated
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Denby, Alistair John. „Intelligent laser scanning for computer aided manufacture“. Thesis, Nottingham Trent University, 2006. http://irep.ntu.ac.uk/id/eprint/210/.
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Reverse engineering requires the acquisition of large amounts of data describing the surface of an object, sufficient to replicate that object accurately using appropriate fabrication techniques. This is important within a wide range of commercial and scientific fields where CAD models may be unavailable for parts that must be duplicated or modified, or where a physical model is used as a prototype. The three-dimensional digitisation of objects is an essential first step in reverse engineering. Optical triangulation laser sensors are one of the most popular and common non-contact methods used in the data acquisition process today. They provide the means for high resolution scanning of complex objects. Multiple scans of the object are usually required to capture the full 3D profile of the object. A number of factors, including scan resolution, system optics and the precision of the mechanical parts comprising the system may affect the accuracy of the process. A single perspective optical triangulation sensor provides an inexpensive method for the acquisition of 3D range image data. However, there are often locations within each scan where data is seriously flawed because the data acquisition process is subject to distortions. Such distortions are often associated with edges in the object, where regions of high curvature (relative to the incident angle of the sensor) cause occlusions and secondary reflections of the laser beam, resulting in false height readings. Abrupt changes in surface reflectance or texture can also have similar effects. Previous work has determined that the orientation of the scan head with respect to the edges of the object is a major factor in the degree of such distortions. Combining multiple range images using compensation algorithms has reduced the level of distortion in the integrated data set; however capturing the number of necessary repetitions of the entire scan is very time-consuming. A development platform has been established to investigate how data distortions may be reduced by the application of image analysis techniques in planning the scan process. By using information on edge location and orientation recovered from a digital camera image, partial scans may then be performed for each determined orientation of the scanner, thereby avoiding much redundant coverage of the entire scan area. Vectorisation algorithms, based on known edge detection techniques, have been developed to determine the position of vectors corresponding to the discovered edges. Further algorithms have been developed to process these vectors into 'scan regions' corresponding to each particular scanner orientation. When the object is scanned at the orientation corresponding to the scan region the distortions are likely to be much reduced. Some features of the object geometry, such as small holes or internal corners present a particular problem where a number of scan regions representing different scan orientations overlap. Because of the nature of the scanner such regions are liable to show some level of distortion for all laser orientations. However, these locations can be identified from the camera image and the user alerted to the presence of unreliable data. Calibration methods relating the image and scan space have been shown to be susceptible to errors caused by optical effects from the camera, such as lens barrel distortion and errors due to parallax. Algorithms have been developed to compensate for these effects and combine the data from a number of partial scans in order to provide a single integrated point cloud.
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Vieira, Pedro. „Tomographic imaging with a scanning laser ophthalmoscope“. Thesis, University of Aberdeen, 1999. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU602005.
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Retinal imaging with a confocal scanning laser Ophthalmoscope (cSLO) involves scanning a small laser beam over the retina and constructing an image from the reflected light. By applying the confocal principle, tomographic images can be produced by measuring a sequence of slices at different retinal depths. However, the thickness of such slices, when compared with the retinal thickness, is too large to give useful 3D retinal images, if no processing is done. In this work, a prototype cSLO was modified in terms hardware and software to give the ability of doing the tomographic measurements with the maximum theoretical axial resolution possible. A model eye was built to test the performance of the system. A novel algorithm has been developed which fits a double Gaussian curve to the axial intensity profiles generated from a stack of images slices. The underlying assumption is that the laser light has mainly been reflected by two structures in the retina, the internal limiting membrane and the retinal pigment epithelium. From the fitted curve topographic images and novel thickness images of the retina can be generated. Deconvolution algorithms have also been developed to improve the axial resolution of the system, using a theoretically predicted cSLO point spread function. The technique was evaluated using measurements made on a model eye, four normal eyes and seven eyes containing retinal pathology. The reproducibility, accuracy and physiological measurements obtained, were compared with available published data, and showed good agreement. The difference in the measurements when using a double rather than a single Gaussian model was also analysed.
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Mohiuddin, Yasneem Fatima. „Photocurrent imaging using a scanning laser microscope“. Thesis, University College London (University of London), 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.369094.
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Hetherington, David. „Terrestrial laser scanning of the river environment“. Thesis, University of Salford, 2009. http://usir.salford.ac.uk/26714/.
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This thesis describes the results of three field studies concerned with the utilisation of terrestrial laser scanning in the river environment, over different spatial scales. Existing research and technical literature has also been reviewed relating to scale, form and process in the river environment, conventional measurement techniques and the general utility and testing of terrestrial laser scanning technology. In physical geography and geomorphology, scales of interest in the river environment can range from very small scales such as an individual grain up to large scales that cover entire floodplains or catchments. Improved measurement and spatial representation of the river environment over all these scales will reduce error and improve confidence in research into river form and process. Terrestrial Laser Scanning (TLS) - sometimes referred to as Terrestrial LiDAR (Light Detection and Ranging) - is an exciting and relatively new measurement technique that is based upon the time-of-flight principles of laser pulses from a static origin. The term "scanning" relates to the way that the laser pulses are systematically deployed and received in an automated fashion over a swath by the main measurement unit. These data are acquired from a terrestrial perspective, which gives the technique an advantage over airborne measurement and terrestrial contact measurement methods. This research's aim is to evaluate the performance of TLS as a tool for measuring and representing the river environment, whilst focusing on three distinct scales of river features - the reach scale, the floodplain/braid plain scale and the grain scale. Overall, TLS has proved itself to be an extremely useful tool for measuring and representing (spatially and temporally) the river environment, whilst focusing on various scales and features. This is especially the case when investigating rivers at the reach and plain scales. If used correctly, it can undoubtedly provide scientists and engineers with the data that they need to increase their knowledge of river environment form and process. The findings of this thesis have many broader implications relating to how TLS should be used and how it fits into the suite of measurement tools that we have at our disposal.
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Vieira, Pedro Manuel Cardoso. „Tomographic imaging with a scanning laser ophtalmoscop“. Doctoral thesis, FCT - UNL, 1999. http://hdl.handle.net/10362/1135.
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Retinal imaging with a confocal scaning laser Ophthalmoscope (cSLO) involves scanning a small laser beam over the retina and constructing an image from the reflected light. By applying the confocal principle, tomographic images can be produced by measuring a sequence of slices at different depths. However, the thickness of such slices, when compared with the retinal thickness, is too large to give useful 3D retinal images, if no processing is done.
In this work, a prototype cSLO was modified in terms hardware and software to give the ability of doing the tomographic measurements with the maximum theoretical axial resolution possible. A model eye was built to test the performance of the system.
A novel algorithm has been developed which fits a double Gaussian curve to the axial intensity profiles generated from a stack of images slices. The underlying assumption is that the laser light has mainly been reflected by two structures in the retina, the internal limiting membrane and the retinal pigment epithelium. From the fitted curve topographic images and novel thickness images of the retina can be generated.
Deconvolution algorithms have also been developed to improve the axial resolution of the system, using a theoretically predicted cSLO point spread function.
The technique was evaluated using measurements made on a model eye, four normal eyes and seven eyes containing retinal pathology. The reproducibility, accuracy and physiological measurements obtained, were compared with available published data, and showed good agreement. The difference in the measurements when using a double rather than a single Gaussian model was also analysed.JNICT - Portugal, Project PRAXIS XXI
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Araújo, Adolfo Lino de. „Cadastro 3D no Brasil a apartir de varredura a laser (laser scanning)“. reponame:Repositório Institucional da UFSC, 2015. https://repositorio.ufsc.br/xmlui/handle/123456789/162764.
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Tese (doutorado) - Universidade Federal de Santa Catarina, Centro Tecnológico, Programa de Pós-Graduação em Engenharia Civil, Florianópolis, 2015.Made available in DSpace on 2016-05-24T17:46:59Z (GMT). No. of bitstreams: 1 338191.pdf: 3929073 bytes, checksum: 3dc093aa57a147d2ce3d53161127f321 (MD5) Previous issue date: 2015
A complexidade e o alto adensamento das áreas urbanas têm contribuÃdo para a ocupação cada vez mais verticalizada da superfÃcie terrestre. Na medida em que novas construções sobre ou sob a superfÃcie surgem, as estruturas dos sistemas cadastrais devem acompanha-las. Tais modificações ocorrem num espaço contÃnuo tridimensional que não pode ser representado adequadamente em duas dimensões. Nos paÃses desenvolvidos e em muitos paÃses em desenvolvimento os sistemas cadastrais têm migrado para incorporar a terceira dimensão, desenvolvendo modelos de dados baseados nos seus registros atuais e nas técnicas disponÃveis, como forma de garantir que intrincados casos de sobreposição do direito de propriedade possam ser equacionados. No cenário internacional há diferentes modelos propostos, desde a manutenção dos Cadastros territoriais tradicionais com o acréscimo de avisos nos tÃtulos de propriedade sobre o uso do espaço aéreo ou do subsolo, passando por modelos hÃbridos de sub-parcelamento da coluna acima e abaixo da superfÃcie terrestre, até os modelos mais completos de parcelas espaciais volumétricas. A proposição de tais modelos é impulsionada por uma realidade técnica e tecnológica atual na qual se tornou possÃvel coletar, processar e representar dados tridimensionais em larga escala, restando, então, a necessidade de atualização das componentes legal e de avaliação. No Brasil, apesar de não haver uma estrutura cadastral parcelar nos termos internacionais, os mesmos problemas se apresentam e surge a possibilidade de se considerar a aplicação de uma terceira dimensão no contexto da legislação nacional. Esta tese procurou avaliar estas possibilidades e propor alternativas para um Cadastro 3D no Brasil utilizando dados provenientes de varredura a laser (laser scanning) aéreo e terrestre.
Abstract : The complexity and the high density of urban areas has contributed to the increasingly verticalized occupation of the land surface. As new buildings under or on the surface appear, the structures of the cadastral systems must accompany them. These changes occur in a three dimensional continuous space that cannot be adequately represented in two dimensions. In developed countries and many developing countries the cadastral systems have migrated to incorporate the third dimension, developing data models based on their current records and techniques available, in order to ensure that intricate cases overlay of property rights can be addressed. Different models have been proposed around the world, since the maintenance of traditional land records with increase warning in property titles about the use of airspace or subsoil, through hybrid models for the sub-parcels above and below of the earth surface, to the complete volumetric spatial parcel models. The proposition of such models is powered by an actual technical and technological reality in which it became possible to collect, process and represent three-dimensional data on a large scale, needing then to update the legal and evaluation components. In Brazil, although there is no a parcel-based registration structure in international terms, the same problems are present and there is the possibility of considering the application of a third dimension in the context of national legislation. This thesis attempts to evaluate these possibilities and propose alternatives for a 3D Cadastre in Brazil using data from laser scanning.
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Araújo, Adolfo Lino de. „Cadastro 3D no Brasil a apartir de varredura a laser (laser scanning)“. reponame:Repositório Institucional da UFSC, 2015. https://repositorio.ufsc.br/xmlui/handle/123456789/169583.
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Tese (doutorado) - Universidade Federal de Santa Catarina, Centro Tecnológico, Programa de Pós-Graduação em Engenharia Civil, Florianópolis, 2015.Made available in DSpace on 2016-10-19T13:12:37Z (GMT). No. of bitstreams: 1 338191.pdf: 3929073 bytes, checksum: 3dc093aa57a147d2ce3d53161127f321 (MD5) Previous issue date: 2015
A complexidade e o alto adensamento das áreas urbanas têm contribuído para a ocupação cada vez mais verticalizada da superfície terrestre. Na medida em que novas construções sobre ou sob a superfície surgem, as estruturas dos sistemas cadastrais devem acompanha-las. Tais modificações ocorrem num espaço contínuo tridimensional que não pode ser representado adequadamente em duas dimensões. Nos países desenvolvidos e em muitos países em desenvolvimento os sistemas cadastrais têm migrado para incorporar a terceira dimensão, desenvolvendo modelos de dados baseados nos seus registros atuais e nas técnicas disponíveis, como forma de garantir que intrincados casos de sobreposição do direito de propriedade possam ser equacionados. No cenário internacional há diferentes modelos propostos, desde a manutenção dos Cadastros territoriais tradicionais com o acréscimo de avisos nos títulos de propriedade sobre o uso do espaço aéreo ou do subsolo, passando por modelos híbridos de sub-parcelamento da coluna acima e abaixo da superfície terrestre, até os modelos mais completos de parcelas espaciais volumétricas. A proposição de tais modelos é impulsionada por uma realidade técnica e tecnológica atual na qual se tornou possível coletar, processar e representar dados tridimensionais em larga escala, restando, então, a necessidade de atualização das componentes legal e de avaliação. No Brasil, apesar de não haver uma estrutura cadastral parcelar nos termos internacionais, os mesmos problemas se apresentam e surge a possibilidade de se considerar a aplicação de uma terceira dimensão no contexto da legislação nacional. Esta tese procurou avaliar estas possibilidades e propor alternativas para um Cadastro 3D no Brasil utilizando dados provenientes de varredura a laser (laser scanning) aéreo e terrestre.
Abstract : The complexity and the high density of urban areas has contributed to the increasingly verticalized occupation of the land surface. As new buildings under or on the surface appear, the structures of the cadastral systems must accompany them. These changes occur in a three dimensional continuous space that cannot be adequately represented in two dimensions. In developed countries and many developing countries the cadastral systems have migrated to incorporate the third dimension, developing data models based on their current records and techniques available, in order to ensure that intricate cases overlay of property rights can be addressed. Different models have been proposed around the world, since the maintenance of traditional land records with increase warning in property titles about the use of airspace or subsoil, through hybrid models for the sub-parcels above and below of the earth surface, to the complete volumetric spatial parcel models. The proposition of such models is powered by an actual technical and technological reality in which it became possible to collect, process and represent three-dimensional data on a large scale, needing then to update the legal and evaluation components. In Brazil, although there is no a parcel-based registration structure in international terms, the same problems are present and there is the possibility of considering the application of a third dimension in the context of national legislation. This thesis attempts to evaluate these possibilities and propose alternatives for a 3D Cadastre in Brazil using data from laser scanning.
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Dizorzi, Matúš. „Adaptivní plánování trajektorie průmyslového robotu“. Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2019. http://www.nusl.cz/ntk/nusl-400667.
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This thesis deals with the extension of the RoScan scanning system features, making its behaviour more secure and adaptivte during scanning of the object on its whole trajectory. This work contains mathematical model of said manipulator, suggested methods to ensure proper behaviour during singularities. New features were added to the RoScan system such as control panel for manipulator control including new format of trajectory log, moving closer or further away from manipulator’s end effector and non adaptive trajectory testing for singularities. Result of this work is ready-to-use.
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Jones, Gary Lewis. „Dynamic scanning, a unique approach to product coding“. Thesis, University of Bristol, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.323631.
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Xu, Zhiheng. „Tracking retinal motion with a scanning laser ophthalmoscope“. Thesis, Georgia Institute of Technology, 2002. http://hdl.handle.net/1853/20171.
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Zator, Maria Malgorzata. „Membrane fouling characterization by confocal scanning laser microscopy“. Doctoral thesis, Universitat Rovira i Virgili, 2009. http://hdl.handle.net/10803/8580.
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En sectores tan diversos como la industria alimentaria, la biotecnología y el tratamiento de aguas residuales, la filtración tangencial con membranas se viene utilizando de forma creciente en la separación, purificación y clarificación de distintas corrientes de proceso que contienen gran variedad de compuestos orgánicos. La limitación principal para el empleo industrial de las técnicas de separación por membranas es el ensuciamiento de éstas. El ensuciamiento se atribuye, de forma general, a la reducción en el diámetro de los poros, a su bloqueo y/o a la formación de un depósito en la superficie de la membrana. El avance en el desarrollo de técnicas para la caracterización, el control y la prevención del ensuciamiento de las membranas ha estado limitado por la falta de técnicas adecuadas y no invasivas para la medición del ensuciamiento. El objetivo principal del presente proyecto es desarrollar estrategias apropiadas para aplicar microscopía láser confocal de barrido (CSLM) al estudio del ensuciamiento de membranas de filtración, centrándose en el ensuciamiento causado por macromoléculas biológicas. En la tesis se han llevado a cabo experimentos de microfiltración (MF) de soluciones modelo puras y de mezclas de proteínas, polisacáridos y polifenoles. Las imágenes captadas mediante CSLM de las membranas al final de diferentes experimentos de filtración, han servido para obtener información cualitativa, sobre localización de las distintas moléculas, y cuantitativa, sobre la presencia individual de cada compuesto en el interior y la superficie de la membrana. Se han realizado también intentos de aplicación de visualización en línea mediante CSLM del proceso de microfiltración.In fields such as the food and dairy industries, biotechnology, and the treatment of industrial effluents, pressure-driven membrane processes such as microfiltration are increasingly being used for the separation, purification and clarification of protein-containing solutions. A major limitation to the widespread use of membrane filtration, however, is fouling. Fouling is usually attributed to pore constriction, pore blocking or the deposition of cells and cell debris on the membrane surface and can lead to a reduction in the filtrate flux of more than an order of magnitude. Progress in developing a means for characterizing, controlling and preventing membrane fouling has been impeded by lack of suitable non-invasive fouling-measurement techniques. The main aim of this study is to develop suitable strategies for applying Confocal Scanning Laser Microscopy (CSLM) to characterise membrane fouling caused by biological macromolecules. Microfiltration experiments of single, binary and ternary model solutions of proteins, polysaccharides and polyphenols were carried out and CSLM images of the membranes at the end of the different filtration runs were obtained, in order to obtain quantitative and qualitative information about fouling patterns. Some trials of on-line monitoring of cross-flow microfiltration processes were also carried out.
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Holmgren, Johan. „Estimation of forest variables using airborne laser scanning /“. Umeå : Dept. of Forest Resource Management and Geomatics, Swedish Univ. of Agricultural Sciences, 2003. http://epsilon.slu.se/s278.pdf.
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Martarelli, Milena. „Exploiting the laser scanning facility for vibration measurements“. Thesis, Imperial College London, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.248035.
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Wang, Chun-Ming Fraser Scott E. „Image enhancement with two-photon laser scanning microscopy /“. Diss., Pasadena, Calif. : California Institute of Technology, 1998. http://resolver.caltech.edu/CaltechETD:etd-01312008-153939.
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Scharf, Alexander. „Terrestrial Laser Scanning for Wooden Facade-system Inspection“. Thesis, Luleå tekniska universitet, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-77159.
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The objective of this study was to evaluate the feasibility of measuring movement, deformation and displacement in wooden façade-systems by terrestrial laser scanning. An overview of different surveying techniques and methods has been created. Point cloud structure and processing was explained in detail as it is the foundation for understanding the advantages and disadvantages of laser scanning. The boundaries of monitoring façades with simple and complex façade structures were tested with the phase-based laser scanner FARO Focus 3DS. In-field measurements of existing facades were done to show the capabilities of extracting defect features such as cracks by laser scanning. The high noise in the data caused by the limited precision of 3D laser scanners is problematic. Details on a scale of several mm are hidden by the data noise. Methods to reduce the noise during point cloud processing have proven to be very data-specific. The uneven point cloud structure of a façade scan made it therefore difficult to find a method working for the whole scans. Dividing the point cloud data automatically into different façade parts by a process called segmentation could make it possible. However, no suitable segmentation algorithm was found and developing an own algorithm would have exceeded the scope of this thesis. Therefore, the goal of automatic point cloud processing was not fulfilled and neglected in the further analyses of outdoor facades and laboratory experiments. The experimental scans showed that several information could be extracted out of the scans. The accuracy of measured board and gap dimensions were, however, highly depended on the point cloud cleaning steps but provided information which could be used for tracking development of a facade’s features. Extensive calibration might improve the accuracy of the measurements. Deviation of façade structures from flat planes were clearly visible when using colorization of point clouds and might be the main benefit of measuring spatial information of facades by non-contact methods. The determination of façade displacement was done under laboratory conditions. A façade panel was displaced manually, and displacement was calculated with different algorithms. The algorithm determining distance to the closest point in a pair of point clouds provided the best results, while being the simplest one in terms of computational complexity. Out-of-plane displacement was the most suitable to detect with this method. Displacement sideways or upwards required more advanced point cloud processing and manual interpretation by the software operator. Based on the findings during the study it can be concluded that laser scanning is not the correct methods for structural health monitoring of facades when the tracking of small deformations, especially deformations below 5 mm and defects like cracks are the main goal. Displacements, defects and deformations of larger scale can be detected but are tied to a large amount of point cloud processing. It is not clear if the equipment costs, surveying time and the problems caused by high variability of scans results based on façade color, shape and texture are in a positive relation to the benefits obtained from using laser scanning over manually surveying.
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Shin, Dong-Ik. „Laser Scanning Imaging for Increased Depth-Of-Focus“. Thesis, Virginia Tech, 2002. http://hdl.handle.net/10919/44190.
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Throughout the decades, different techniques have been proposed to improve the depth-of-focus in optical microscopy. Common techniques like optical sectioning microscopy and scanning confocal microscopy have innate problems. By simply modifying the pupil function in microscope imaging system, we can also extend the depth-of-focus. The scanning system with a thin annular pupil has a high depth-of-focus and can scan the whole object, but the output light is too dim to be detected well by a photodetector.
In this thesis, we propose a scanning technique employing an optical heterodyne scanning system using a difference-of-Gaussians (DoG) pupil. The object is illuminated by the combined beam which consists of two Gaussian beams with different waists, frequencies, and amplitudes. This system does not block most light like the annular pupil system and can obtain high depth-of-focus. The main objective of the thesis is to extend the depth-of-focus using the proposed system. The depth-of-focus characteristics of the DoG pupil function are examined and compared with those of well-known functions such as the circular, annular, and Gaussian pupils.Master of Science
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Manivannan, Ayyakkannu. „Digital fundus imaging with a scanning laser ophthalmoscope“. Thesis, University of Aberdeen, 1993. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU602038.
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A prototype scanning laser ophthalmoscope was constructed based on the original principles of Webb et al (1987 and 1990). The basic design was, however, altered in a number of ways to give the flexibility needed for what was primarily a research instrument with a requirement to use lasers of various wavelengths and to carry out confocal imaging with a variety of slice thicknesses. Some of the performance characteristics of the prototype SLO, such as modulation transfer function, axial resolution and uniformity of illumination were measured and are presented. The SLO can operate in three different modes; direct, confocal and indirect. The direct mode imaging has a large depth of focus and collects light from all layers of the fundus. High contrast imaging is possible due to scattered light being significantly reduced as only a single spot is illuminated at a time. Confocal imaging further improves the contrast by collecting light only from a small slice of the fundus. The capacity to carry out confocal imaging is a significant advantage over fundus cameras. By moving the confocal aperture, light from different layers could be collected enabling the visualisation of various lesions. The indirect mode collects only the scattered light, avoiding the directly reflected light. The clinical value of the equipment was evaluated with a small number of patients with various pathological conditions from the Eye Out-patient Clinic of the Aberdeen Royal Infirmary. The images from the SLO were compared with fundus photographs. The confocal capability, together with the penetrating capacity of near infrared illumination, was utilised to demonstrate the ability to visualise deep lying structures such as choroidal vessels and intra- retinal abnormalities. Near infrared illumination was found useful for imaging through media opacities, such as cataracts. The indirect mode was found useful for visualising structures such as drusen and epiretinal membrane. It is concluded that near infrared monochromatic imaging with the SLO offers a 'new' picture of the fundus. The confocal capability provides the ability to produce 3-D images of the fundus. The near infrared reflective characteristics of many normal and pathological tissues appear to offer new clinical insights into fundal pathology. However, more work is needed to fully appreciate the clinical potential of this new imaging modality.
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Boruah, Bosanta Ranjan. „Programmable diffractive optics for laser scanning confocal microscopy“. Thesis, Imperial College London, 2007. http://hdl.handle.net/10044/1/11911.
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Lewark, Erick A. „Automated techniques in anthropometry using a three dimensional laser scanner“. Ohio : Ohio University, 1998. http://www.ohiolink.edu/etd/view.cgi?ohiou1176485676.
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Zogg, Hans Martin. „Investigations of high precision terrestrial laser scanning with emphasis on the development of a robust close-range 3D-laser scanning system /“. Zürich : ETH, 2008. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=18013.
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Liu, Junjie. „3D laser scanner development and analysis“. Thesis, Aberystwyth University, 2013. http://hdl.handle.net/2160/b3a1beca-3d92-48bc-945e-2e50b3e7755a.
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This PhD project is a collaboration between Smart Light Devices, Ltd. in Aberdeen and Aberystwyth University on the development of such 3D laser scanners with an ultimate aim to inspect the underwater oil and gas pipes or structure. At the end of this project, a workable and full functional 3D laser scanner is to be developed. This PhD project puts a particular emphasis on the engineering and implementation of the scanner according to real applications’ requirements. Our 3D laser scanner is based on the principle of triangulation and its high accuracy over a short range scanning. Accurate 3D data can be obtained from a triangle between the scanner, camera lens, laser source, and the object being scanned. Once the distance between the scanner camera lens and laser source (stereo baseline) is known and the laser projection angle can be measured by the goniometer, all the X, Y,Z coordinates of the object surface can be obtained through trigonometry. This 3D laser scanner development involves a lot of issues and tasks including image noise removal, laser peak detection, corner detection, camera calibration and 3D reconstruction. These issues and tasks have been addressed, analysed and improved during the PhD period. Firstly, the Sparse Code Shrinkage (SCS) image de-noise is implemented, since it is one of the most suitable de-noising methods for our laser images with dark background and white laser stripe. Secondly, there are already plenty of methods for corner and laser peak detection, it is necessary to compare and evaluate which is the most suitable for our 3D laser scanner. Thus, comparative studies are carried out and their results are presented in this thesis. Thirdly, our scanner is based on laser triangulation, in this case, laser projection angle α and baseline distance D from the centre of the camera lens to laser source plays a crucial role in 3D reconstruction. However, these two parameters are hard to measure directly, and there are no particular tools designed for this purpose. Thus, a new approach is proposed in this thesis to estimate them which combines camera calibration results with the precise linear stage. Fourthly, it is very expensive to customize an accurate positional pattern for camera calibration, due to budget limit, this pattern is printed by a printer or even painted on a paper or white board which is inaccurate and contains errors in absolute distance and location. An iterative camera calibration method is proposed. It can compensate up to 10% error and the calibration parameters remain stable. Finally, in the underwater applications, the light travel angle is changed from water to air which makes the normal calibration method less accurate. Hence, a new approach is proposed to compensate between the estimate and real distance in 3D reconstruction with normal calibration parameters. Experimental results show the proposed methods reduce the distance error in 3D down to ±0.2mm underwater. Overall, the developed scanning systems have been successfully applied in several real scanning and 3D modelling projects such as mooring chain, underwater pipeline surface and reducer. Positive feedback has been received from these projects, the scanning results satisfy the resolution and accuracy requirements.
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Yildiz, Bilge Can. „Imaging Of Metal Surfaces Using Confocal Laser Scanning Microscopy“. Master's thesis, METU, 2011. http://etd.lib.metu.edu.tr/upload/12613641/index.pdf.
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Optical imaging techniques have improved much over the last fifty years since the invention of the laser. With a high brightness source many imaging applications which were once inaccessible to researchers have now become a reality. Among these techniques, the most beneficial one is the use of lasers for both wide-field and
confocal imaging systems.
The aim of this study was to design a laser imaging system based on the concept of laser scanning confocal microscopy. Specifically the optical system was based on optical fibers allowing the user to image remote areas such as the inner surface of rifled gun barrels and/or pipes with a high degree of precision (+/- 0.01 mm). In order to build such a system, initially the theoretical foundation for a confocal as well as a wide-field imaging system was analyzed. Using this basis a free-space optical confocal system was built and analyzed. The measurements support the fact that both the objective numerical aperture and pinhole size play an important role in the radial and axial resolution of the system as well as the quality of the images obtained.
To begin construction of a confocal, optical-fiber based imaging system first an all fiber wide-field imaging system was designed and tested at a working wavelength of 1550 nm. Then an all fiber confocal system was designed at a working wavelength of 808 nm. In both cases results showed that while lateral resolution was adequate, axial resolution suffered since it was found that the design of the optical system needs to take into account under-filling of the objective lens, a result common with the use of laser beams whose divergence is not at all like that of a point source.
The work done here will aid technology that will be used in the elimination process of faulty rifling fabrication in defense industry. The reason why the confocal technique is preferred to the conventional wide-field one is the need for better resolution in all directions. Theoretical concepts and mathematical background are discussed as well as the experimental results and the practical advantages of such a system.
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Abdelmajid, Yezeed. „Investigation and Comparison of 3D Laser Scanning Software Packages“. Thesis, KTH, Geodesi och geoinformatik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-102421.
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Laser scanning technologies has become an important tool in many engineering projects and applications. The output of laser measuring is the point cloud, which is processed in a way that makes it suitable for different applications. Processing of point cloud data is achieved through laser scanning software packages. Depending on the field of application, these packages have many different kinds of functions and methods that can be used. The main processing tasks used on a laser scanning software package include registration, modelling and texture mapping. Investigation and comparison of two laser scanning processing packages (Leica Cyclone and InnovMetric PolyWorks) are performed in this study. The theoretical and mathematical backgrounds of the above functions are presented and discussed. The available methods and functions used by each of the packages for these tasks are addressed and discussed. By using sample data, these functions are trailed and their results are compared and analyzed. The results from registration tests show the same results on both packages for the registration using target methods. Although, the results of cloud-to-cloud registration show some deviation from target registration results, they are more close to each other in both packages than to the target registration results. This indicates the efficiency of cloud-to-cloud methods in averaging the total registration error on all used points, unlike target registration methods. The modelling tests show more differences in the accuracy of generated models between the two packages. For both fitting and surface construction methods, PolyWorks showed better results and capabilities for three-dimensional modelling. As a result, the advantages and disadvantages of each package are presented in relation with the used task and methods, and a review of data exchange abilities is presented.
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Luedtke, Michael A. Papazoglou Elisabeth S. „Wavelength effects on in vivo confocal scanning laser microscopy/“. Philadelphia, Pa. : Drexel University, 2007. http://hdl.handle.net/1860/2518.
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Cobley, R. J. „Cross-sectional scanning tunnelling microscopy of biased laser structures“. Thesis, Swansea University, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.636273.
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This work investigates Cross-Sectional Scanning Tunnelling Microscopy applied to semiconductor laser structures which are biased whilst they are being scanned. Images are presented as a function of sample bias. Increasing the sample bias removes the built-in band bending across the device and causes the horizontal topographic gradient of the scan to change. The p-type side of the sample is held at ground whilst the n-type side is biased. When tunnelling out of a double quantum well structure the topographic height of the n-type side increases by around 0.2nm at 1V. Tunnelling in to the structure, the height decreases by 0.02nm under low tunnelling current conditions. A tunnelling current model is developed which confirms these changes. Tunnelling in to a buried heterostructure device the apparent topographic height of the n-type side is again found to decrease, by over 2nm. Biased-dependent spectroscopic shifts are also observed with this device which are again confirmed by modelling. In both devices the apparent height of the quantum wells is found to increase by a factor of 2.5 to 4 times, at 1V sample bias. This is caused by the effects of tip-induced band bending being altered by the applied bias. An experimental and modelled example of a superlattice structure which displays contrast enhancement through tip-induced band bending is given. Several other device-specific physical and irreversible changes occur as a result of sample bias. These are well-suited to give characterisation information not available from other techniques.
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Jiang, Shihong. „Non-scanning fluorescence confocal microscopy using laser speckle illumination“. Thesis, University of Nottingham, 2005. http://eprints.nottingham.ac.uk/10139/.
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Confocal scanning microscopy (CSM) is a much used and advantageous form of microscopy. Although CSM is superior to conventional microscopy in many respects, a major disadvantage is the complexity of the scanning process and the sometimes long time to perform the scan. In this thesis a novel non-scanning fluorescence confocal microscopy is investigated. The method uses a random time-varying speckle pattern to illuminate the specimen, recording a large number of independent full-field frames without the need for a scanning system. The recorded frames are then processed in a suitable way to give a confocal image. The goal of this research project is to confirm the effectiveness and practicality of speckle-illumination microscopy and to develop this proposal into a functioning microscope system. The issues to be addressed include modelling of the system performance, setting up experiments, computer control and image processing. This work makes the following contributions to knowledge: * The development of criteria for system performance evaluation * The development of methods for speckle processing, whereby the number of frames required for an image of acceptable quality can be reduced * The implementation of non-scanning fluorescence confocal microscopy based upon separate recording of the speckle patterns and the fluorescence frames, demonstrating the practicality and effectiveness of this method * The realisation of real-time image processing by optically addressed spatial light modulator, showing how this new form of optical arrangement may be used in practice The thesis is organised into three main segments. Chapters 1-2 review related work and introduce the concepts of fluorescence confocal microscopy. Chapters 3-5 discuss system modelling and present results of performance evaluation. Chapters 6-8 present experimental results based upon the separate recording scheme and the spatial light modulation scheme, draw conclusions and offer some speculative suggestions for future research.
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Kucernak, Anthony Robert John. „Scanning laser photoelectrochemical studies of oxide films on metals“. Thesis, University of Southampton, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.305577.
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Alshawabkeh, Yahya. „Integration of laser scanning and photogrammetry for heritage documentation“. [S.l. : s.n.], 2006. http://nbn-resolving.de/urn:nbn:de:bsz:93-opus-28994.
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Reshetyuk, Yuriy. „Self-calibration and direct georeferencing in terrestrial laser scanning“. Doctoral thesis, Stockholm : Arkitektur och samhällsbyggnad, Kungliga Tekniska högskolan, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-9879.
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Olsen, Michael James. „Methodology for assessing coastal change using terrestrial laser scanning“. Diss., [La Jolla] : University of California, San Diego, 2009. http://nsgl.gso.uri.edu/casg/casgy09005.pdf.
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Thesis (Ph. D.)--University of California, San Diego, 2009.Title from first page of PDF file (viewed July 14, 2009). Available via ProQuest Digital Dissertations. Vita. Includes bibliographical references (p. 258-267).
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Evans, Hywel F. J. „Construction material classification using multi-spectral terrestrial laser scanning“. Thesis, University of Nottingham, 2016. http://eprints.nottingham.ac.uk/33511/.
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This research addresses the problem of populating Building Information Model databases with information on building construction materials using a new classification method which uses multi-spectral laser scanning intensity and geometry data. Research in multi-spectral laser scanning will open up a new era in survey and mapping; the 3D surface spectral response sensitive to the transmitted wavelengths could be derived day or night in complex environments using a single sensor. At the start of this research a commercial multi-spectral sensor did not exist, but a few prototype level instruments had been developed; this work wished to get ahead of the hardware development and assess capability and develop applications from multi-spectral laser scanning. These applications could include high density topographic surveying, seamless shallow water bathymetry, environmental modelling, urban surface mapping, or vegetative classification. This was achieved by using from multiple terrestrial laser scanners, each with a different laser wavelength. The fused data provided a spectral and geometric signature of each material which was subsequently classified using a supervised neural network. The multi-spectral data was created by precise co-positioning of the scanner optical centres and sub-centimetre registration using common sphere targets. A common point cloud, with reflected laser intensity values for each laser wavelength, was created from the data. The three intensity values for each point were then used as input to the classifier; ratios of the actual intensities were used to reduce the effect of range and incidence angle differences. Analysis of five classes of data showed that they were not linearly separable; an artificial neural network classifier was the chosen classifier has been shown to separate this type of data. The classifier training dataset was manually created from a small section of the original scan; five classes of building materials were selected for training. The performance of the classification was tested against a reference point cloud of the complete scene. The classifier was able to distinguish the chosen test classes with a mean rate of 84.9% and maximum for individual classes of 100%. The classes with the highest classification rate were brick, gravel and pavement. The success rate was found to be affected by several factors, among these the most significant, inter-scan registration, limitation on available wavelengths and the number of classes of material chosen. Additionally, a method which included a measure of texture through variations in intensity was tested successfully. This research presents a new method of classifying materials using multi-spectral laser scanning, a novel method for registering dissimilar point clouds from different scanners and an insight into the part played by laser speckle interpretation of reflected intensity.
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Cohat, Hervé. „Le SLO (Scanning Laser Ophthalmoscope) : principes d'utilisation et applications“. Montpellier 1, 1993. http://www.theses.fr/1993MON11167.
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Antoine, Marc M. E. „A rapidly scanning three-velocity-component laser Doppler anemometer“. Thesis, Virginia Polytechnic Institute and State University, 1985. http://hdl.handle.net/10919/104288.
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Resop, Jonathan Patrick. „Terrestrial Laser Scanning for Quantifying Uncertainty in Fluvial Applications“. Diss., Virginia Tech, 2010. http://hdl.handle.net/10919/38694.
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Stream morphology is an important aspect of many hydrological and ecological applications such as stream restoration design (SRD) and estimating sediment loads for total maximum daily load (TMDL) development. Surveying of stream morphology traditionally involves point measurement tools, such as total stations, or remote sensing technologies, such as aerial laser scanning (ALS), which have limitations in spatial resolution. Terrestrial laser scanning (TLS) can potentially offer improvements over other surveying methods by providing greater resolution and accuracy. The first two objectives were to quantify the measurement and interpolation errors from total station surveying using TLS as a reference dataset for two fluvial applications: 1) measuring streambank retreat (SBR) for sediment load calculations; and 2) measuring topography for habitat complexity quantification. The third objective was to apply knowledge uncertainties and stochastic variability to the application of SRD.
A streambank on Stroubles Creek in Blacksburg, VA was surveyed six times over two years to measure SBR. Both total station surveying and erosion pins overestimated total volumetric retreat compared to TLS by 32% and 17%, respectively. The error in SBR using traditional methods would be significant when extrapolating to reach-scale estimates of sediment load. TLS allowed for collecting topographic data over the entire streambank surface and provides small-scale measurements on the spatial variability of SBR.
The topography of a reach on the Staunton River in Shenandoah National Park, VA was measured to quantify habitat complexity. Total station surveying underestimated the volume of in-stream rocks by 55% compared to TLS. An algorithm was developed for delineating in-stream rocks from the TLS dataset. Complexity metrics, such as percent in-stream rock cover and cross-sectional heterogeneity, were derived and compared between both methods. TLS quantified habitat complexity in an automated, unbiased manner at a high spatial resolution.
Finally, a two-phase uncertainty analysis was performed with Monte Carlo Simulation (MCS) on a two-stage channel SRD for Stroubles Creek. Both knowledge errors (Manning's n and Shield's number) and natural stochasticity (bankfull discharge and grain size) were incorporated into the analysis. The uncertainty design solutions for possible channel dimensions varied over a range of one to four times the magnitude of the deterministic solution. The uncertainty inherent in SRD should be quantified and used to provide a range of design options and to quantify the level of risk in selected design outcomes.Ph. D.
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Slaker, Brent Allan. „Monitoring Underground Mine Displacement Using Photogrammetry and Laser Scanning“. Diss., Virginia Tech, 2015. http://hdl.handle.net/10919/51691.
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Photogrammetry and laser scanning are remote sensing technologies with the potential to monitor movements of rock masses and their support systems in underground mine environments. Displacements underground are traditionally measured through point measurement devices, such as extensometers. These are generally restricted to measuring one dimension, may change behavior with installation, may obstruct mining operations, and are restricted to monitoring the behavior of a small area. Photogrammetry and laser scanning offer the ability to monitor rock mass movements at millions of points in a local area, both accurately and quickly. An improved, or augmented, method for measuring displacements underground in a practical, cost-effective manner will lead to an improved understanding of rock mass behavior.
Several experiments were performed that demonstrate the applicability of these remote sensing techniques to monitoring rock mass changes. An underground mining environment presents unique challenges to using these tools for monitoring rock movements, such as: poor lighting, dust, fog, and unfavorable geometries. It is important, therefore, to demonstrate that these tools which have applications in other industries, can also be adapted to the conditions of an underground mine. The study sites chosen include two different underground limestone mines, two different underground coal mines, and the Mine Roof Simulator (MRS) at the Pittsburgh Office of Mine Safety and Health Research.
Both photogrammetry and laser scanning were tested at different limestone mines to detect scaling and spalling on ribs that occurred over several weeks. Both methods were successfully used to reconstruct three-dimensional models of the limestone ribs and detect areas of rock change between visits. By comparing the reconstructed point clouds, and the triangulated meshes created from them, volumes of rock change could be quantified. The laser scanned limestone mine showed a volume of 2.3 m3 and 2.6 m3 being displaced across two ribs between visits. The photogrammetry study involved seven different pillars and at least one rib face modeled on each, with volume changes of 0.29 to 4.03 m3 detected between visits. The rock displaced from the ribs could not be measured independently of the remote sensing, but a uniform absence of rock movement across large areas of the mine validates the accuracy of the point clouds. A similar test was performed using laser scanning in an underground coal mine, where the displacement was induced by removing material by hand from the ribs. Volume changes as small as 57 cm3, or slightly larger than a golf ball, and as large as 57,549 cm3, were detectable in this environment, despite the change in rib surface reflectance and mine geometry.
In addition to the rib displacement, photogrammetry was selected as a tool for monitoring standing supports in underground coal mines. The additional regulatory restrictions of underground coal may preclude the use of laser scanning in these mines where deformation is most likely to occur. The camera used for photogrammetry is ATEX certified as explosion proof and is indicative of the specifications that could be expected in an MSHA approved camera. Three different experiments were performed with this camera, including a laboratory controlled standing support deformation at the MRS and an in-mine time-lapse experiment measuring the response of a wooden crib and steel support to abutment loading. The experiment reconstructing a standing support in the MRS showed a cumulative convergence of 30.93 cm through photogrammetry and 30.48 cm as measured by the system. The standing support monitoring in the underground coal mine environment showed a steel support cumulative convergence of 1.10 cm, a wooden crib cumulative convergence of 0.62 cm, and a measured cumulative convergence on the wooden crib of 0.62 cm.
These techniques explored in this report are not intended to supplant, but rather supplement, existing measurement technologies. Both laser scanning and photogrammetry have physical and regulatory limitations in their application to measuring underground mine deformations, however, their ability to provide time-lapse three-dimensional measurements of entire mine sections is a strength difficult to emulate with traditional point measurement techniques. A fast, cost-effective, and practical application of remote sensing to monitoring mine displacements will improve awareness and understanding of rock mass behavior.Ph. D.