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Hydrothermal activity is one of the dominant processes affecting the chemical and thermal evolution of oceanic crust at the mid-ocean ridge (MOR), but little is known about the sub-surface portions of ridge hydrothermal systems. These systems can be investigated using numerical modeling techniques, and models of two-dimensional cross-sections are utilized in this study to investigate the behavior of MOR hydrothermal systems. The influence of magma chamber geometry is explored by modeling two extremes of proposed geometry. Seismological evidence supports a dike-like 2 km half-width chamber, and models of this chamber indicate that: (1) complete crystallization of the magma requires 30,000 years, (2) hydrothermal upflow and hot springs are concentrated in a narrow band within 1.5 km of the ridge axis for the lifetime of the system, (3) a large hydrothermal cell forms and remains centered above the distal tip of the intrusion for the lifetime of the system, (4) effective hydrothermal activity ends by 70,000 yrs. Petrological evidence supports a wide sill-like chamber 15 km in half-width, and models of this chamber indicate that: (1) complete crystallization of the magma requires 100,000 yrs, (2) hydrothermal vents are present at the ridge axis, but most of the vents are located 5-10 km away from the axis, (3) a large hydrothermal cell develops at the distal tip of the magma chamber, while a series of small but vigorous cells develops directly above the intrusion, both features migrate toward the ridge axis as the magma solidifies, (4) effective hydrothermal activity ends by 170,000 yrs. Substantially different hydrothermal systems develop around these two chamber geometries and comparison of the models shows this is because different patterns of near-critical P-T conditions developed around them. The fundamental influence on the nature and pattern of hydrothermal circulation at MOR is the distribution of near-critical conditions.

The term biometrics is used to describe the process of analyzing biological and behavioral traits that are unique to an individual in order to confirm or determine his or her identity. Many biometric modalities are currently being researched and implemented including, fingerprints, hand and facial geometry, iris recognition, vein structure recognition, gait, voice recognition, etc... This project explores the possibility of using corneal topography measurements as a trait for biometric identification. Two new corneal topographers were developed for this study. The first was designed to function as an operator-free device that will allow a user to approach the device and have his or her corneal topography measured. Human subject topography data were collected with this device and compared to measurements made with the commercially available Keratron Piccolo topographer (Optikon, Rome, Italy). A third topographer that departs from the standard Placido disk technology allows for arbitrary pattern illumination through the use of LCD monitors. This topographer was built and tested to be used in future research studies. Topography data was collected from 59 subjects and modeled using Zernike polynomials, which provide for a simple method of compressing topography data and comparing one topographical measurement with a database for biometric identification. The data were analyzed to determine the biometric error rates associated with corneal topography measurements. Reasonably accurate results, between three to eight percent simultaneous false match and false non-match rates, were achieved.

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No description available.

The current study examines anecdotal assessment, functional analysis, and treatment outcomes from 44 participants. Agreement across Motivation Assessment Scale (MAS), Questions About Behavioral Function (QABF), and Functional Analysis Screening Tool (FAST) assessments, agreement between those anecdotal assessments and functional analyses, and agreement between those anecdotal assessments and treatment outcomes were analyzed across maintaining variables and topography categories of challenging behaviors. Overall, the QABF had the highest agreement results with functional analyses and treatment with 70% and 92% of cases respectively. Patterns in the distribution of maintaining variables was examined across behavior topography categories.

Purpose: To compare and analyze the differences in visual outcomes between Visx iDesign Advanced WaveScan Studio (TM) System, Alcon Wavelight Allegro Topolyzer and Nidek EC-5000 using Final Fit (TM) Custom Ablation Treatment Software from the submitted summary of safety and effectiveness of the US Food and Drug Administration (FDA) data. Methods: In this retrospective comparative study, 334 eyes from Visx iDesign, 212 eyes from Alcon Contour, and 135 eyes from Nidek CATz platforms were analyzed for primary and secondary visual outcomes. These outcomes were compared via side-by-side graphical and tabular representation of the FDA data. Statistical significance was calculated when appropriate to assess differences. A P-value <0.05 was considered statistically significant. Results: The mean postoperative uncorrected distance visual acuity (UDVA) at 12 months was 20/19.25 +/- 8.76, 20/16.59 +/- 5.94, and 20/19.17 +/- 4.46 for Visx iDesign, Alcon Contoura, and Nidek CATz, respectively. In at least 90% of treated eyes at 3 months and 12 months, all three lasers showed either no change or a gain of corrected distance visual acuity (CDVA). Mesopic contrast sensitivity at 6 months showed a clinically significant increase of 41.3%, 25.1%, and 10.6% for eyes using Visx iDesign, Alcon Contoura, and Nidek CATz, respectively. Photopic contrast sensitivity at 6 months showed a clinically significant increase of 19.2%, 31.9%, and 10.6% for eyes using Visx iDesign, Alcon Contoura, and Nidek CATz, respectively. Conclusion: FDA data for the three platforms shows all three were excellent with respect to efficacy, safety, accuracy, and stability. However, there are some differences between the platforms with certain outcome measurements. Overall, patients using all three lasers showed significant improvements in primary and secondary visual outcomes after LASIK surgery.

This thesis examines the evolution of the now dominant contour method of relief representation, associated interpretation problems and attempted solutions. A hybrid method of relief representation is then suggested combining a standard topographic map, to provide quantitative data, and computer generated three-dimensional visualisations, to give topographic structure. The hypothesis that this system will result in improved performance at relief interpretation tasks, particularly for inexperienced map users, was then tested. A second aspect of the hypothesis centred on the colouring of the 3-D views. Thus the experiment was expanded to assess if the more natural impression provided by layer colouring resulted in improved performance. The principle evaluation involved 2 Objective Tests of user performance. Subjective assessment of 3-D visualisation production and quality and Opinion Samples were also used in the overall evaluation. This thesis concludes that the three-dimensional information tested here has not produced the expected improvement. Reasons suggested for this include lack of training with 2 and 3 dimensional data, unfamiliarity with computer generated three-dimensional views and inability of inexperienced map users to manipulate complex three-dimensional imagery. Suggested improvements to the theory include increased training and use of more specifically targeted views, for example, to illustrate a walking route using a series of views along its course.

Orientador: Zacarias Xavier de Barros / Banca: Luis Gustavo Frediani Lessa / Banca: Diego Augusto de Campos Moraes / Resumo: A atividade agrícola tem importância significativa na economia, justificando diversas pesquisas que busquem a aquisição de informações e desenvolvimento de tecnologias para que os processos envolvidos sejam mais eficientes. A topografia, geodésia e geoprocessamento têm sido utilizados de forma crescente e de diversas formas, tanto para monitoramento, quanto para planejamento na gestão agronômica e dos recursos naturais. O presente trabalho foi realizado na Fazenda Experimental Lageado, em Botucatu-SP e teve por objetivo aferir cartas do IGC e IBGE em comparação com equipamentos de alta precisão, nas quais foram confeccionadas linhas de perfis altimétricos e interpolação dos valores de altimetria. A geoestatística foi utilizada para uma interpolação com predição de erros, na qual os semi-variogramas e a validação cruzada permitiram analisar a correlação espacial e variância dos dados estimados. Como resultados foram obtidos mapas de altimetria, declividade e respectivos residuais altimétricos absolutos para a mensuração da confiabilidade de cartas na classificação de relevo, como também, o uso de cartas para traçado de limites de confrontações naturais, como linhas de cumeada e grota. Pôde-se concluir que não é confiável utilizar as cartas para determinação de limites de confrontação natural como linhas de cumeadas e grotas para certificação de cadastro de registro de imóveis. / Abstract: The agriculture has a significant importance in economy, demanding several researches that allow information acquisition and technology development aiming an enhancing of the processes involved. Land surveying, geodetic sciences and geoprocessing have been more applied, and in different ways for land monitoring, soil and nature resources management. The present essay was developed on the Experimental Farm Fazenda Experimental Lageado Botucatu - SP, Brazil and aimed an altimetry analysis of IGC and IBGE contour maps with accurate instruments as parameters, in which altimetry profile lines and interpolation of the altitude values were made. The kriging process was used, likewise the semi variogram model, and further the cross validation was made to achieve a known function for the altimetry value's estimation, spatial correlation and value of variance. Digital elevation models, slope maps and the respective absolute altimetry residuals were made to measure the reliability of the IGC and IBGE contour maps as well as its usefulness for obtaining land topography and natural boundary from gardenbed or flume. It was concluded that the IGC and IBGE contour maps are not reliable for obtaining natural boundary from gardenbed or flume for certification of land registry in Brazil, although IGC contour maps were fine enough for morphometric analysis of small basins. IBGE contour maps as last ... / Mestre

Reaches dominated by debris flow scour and incision tend to greatly influence landscape form in steepland basins. Debris flow networks, despite their ubiquity, have not been exploited to develop erosion rate proxies. To bridge this gap, I applied a proposed empirical function that describes the variation of valley slope with drainage area in fluvial and debris flow reaches of steepland channel networks in the Oregon Coast Range. I calibrated a relationship between profile concavity and erosion rate to map spatial patterns of long-term uplift rates assuming steady state. I also estimated the magnitude and inland extent of coseismic subsidence in my study area. My estimates agree with field measurements in the same area along the Cascadia margin, indicating that debris flow valley profiles can be used to make interpretations from spatial patterns of rock uplift that may better constrain physical models of crustal deformation. This thesis includes unpublished co-authored material.