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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
141

Short wave infrared spectral response of fluvial channel sands in the Towamba River, NSW, Australia : implications for sediment tracing

Crowell, Kelly Jean, Geography & Oceanography, Australian Defence Force Academy, UNSW January 2002 (has links)
Emergent spatial signals which may be interpreted in the context of fluvial sediment transport processes are detected through the use of reflectance spectroscopy in the sand-sized sediments of the Towamba River, southeastern New South Wales. Reflectance spectroscopy of sufficiently fine spectral resolution represents a technique for mineral composition analysis which is complementary to X-ray diffraction, with advantages in terms of ease of sample preparation and rapidity of measurement. Instrumentation is available allowing high-quality spectrum acquisition in the field and from airborne and satellite-borne instruments. The former allows mineral analyses to more easily be incorporated into sediment tracing studies as an additional variable. The latter offers large scale, repeatable areal coverage of a dynamic system in which sediments are exposed to the sky. The Towamba River drains a catchment of c. 1000 km [square] in extensively altered granitic terrain along the south coast of New South Wales, and carries significant quantities of sand-sized sediment through much of the system. Pervasive but spatially variable chlorite, epidote, and sericite have been described in local and neighbouring terrain. These are spectrally active in the SWIR wavelength region in which the PIMA portable spectrometer operates. The airborne HyMap instrument is sensitive through this range as well as through the visible and near-infrared regions. Conventionally such channel sediments would represent a single class in the context of the broader landscape, and comparatively they represent a domain of restricted variance. In this study of samples of sediment were collected for analysis with the PIMA, the results of which supported the efficacy of such an exercise in a conventional tracing context and supported analysis of HyMap imagery. Although issues related to reduction of HyMap-detected radiance to reflectance prevented effective analysis of the shorter wavelengths sensitive to the presence of ferrous and ferric iron, the consideration of absorption feature depths and the application of a matched filtering operator revealed gross-scale spatial patterns which were interpreted as two populations of sand in the main channel. This interpretation is consistent with bank erosion occurring during two very large magnitude flow events in the 1970s, with minor ongoing perturbation of the sediment signal in the main channel by the contribution of sediment from tributaries. The presence of a definite spatial signal having been established, routes for further investigation are suggested. A noisy signal hypothesised on the basis of imagery may be used to better direct a field sampling program for a conventional sediment tracing study. The signal to noise ratio may be improved for example through calibration of radiance to reflectance and removal of atmospheric interference and improved field sampling schemes, after which more rigorous, quantitative exercises such as geostatistical ???field??? trial or spatial series analysis may be performed. Connections to process through sediment transport models are enabled through the use of GIS.
142

In situ sensing for chemical vapor deposition based on state estimation theory

Xiong, Rentian. January 2007 (has links)
Thesis (Ph. D.)--Chemical and Biomolecular Engineering, Georgia Institute of Technology, 2008. / Committee Chair: Gallivan, Martha; Committee Member: Ferguson, Ian; Committee Member: Henderson, Cliff; Committee Member: Hess, Dennis; Committee Member: Lee, Jay.
143

Normative measurements of energy reflectance in healthy newborns and one-month olds

Merchant, Gabrielle R. January 2009 (has links)
Honors Project--Smith College, Northampton, Mass., 2009. / Includes bibliographical references (p. 63-64).
144

Incorporating structural information into interpretation of satellite images of forests /

Gu, Degui. January 1998 (has links)
Thesis (Ph. D.)--University of Washington, 1998. / Vita. Includes bibliographical references (leaves [130]-138).
145

Simulation of bidirectional reflectance, modulation transfer, and spatial interaction for the probabilistic classification of Northwest forest structures using Landsat data /

Moffett, Jeffrey Lee. January 1998 (has links)
Thesis (Ph. D.)--University of Washington, 1998. / Vita. Includes bibliographical references (p. [248]-277).
146

Quantitative Analysen magmatischer Gesteine mittels reflexionsspektroskopischer Infrarot-Messungen /

Schodlok, Martin C. January 1900 (has links)
Thesis (doctoral)--Universität Potsdam, 2004. / "August 2004"--P. [2] of cover. Includes bibliographical references (p. 102-108). Also available via the World Wide Web.
147

Antenna coupled infrared detectors for wavelength selectivity or broadband absorption

Han, Sangwook, January 1900 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2006. / Vita. Includes bibliographical references.
148

The relation between spectral reflectance and dissolved organic carbon in lake water ; Kejimkujik National Park, Nova Scotia /

Hirtle, Heather D. M. January 1900 (has links)
Thesis (M.A.)--Carleton University, 2001. / Includes bibliographical references (p. 90-95). Also available in electronic format on the Internet.
149

Impact of protein source and vitamin stability on broiler performance

Frempong, Nana Serwah January 1900 (has links)
Master of Science / Department of Grain Science and Industry / Charles R. Stark / A study was carried out to determine the effect of replacing fish meal with either soybean meal or poultry by-product meal on broiler performance and total feed cost per kg of gain. A second study evaluated the effect of storage time and trace minerals on the stability of vitamins stored at high temperature and relative humidity and their subsequent effects on broiler performance, bone strength and ash. A third study consisting of two experiments was conducted to determine the effects of particle size, diet, method of analysis (laboratory, ground and unground) and feed form (mash and pellet) on the crude protein predictability of the near infrared reflectance spectroscopy while using standard calibrations installed with the instrument. In study 1, three dietary treatments, 1) SBM-FM diet, 2) SBM diet and 3) SBM-PBM diet, were allocated to 36 pens using a completely randomized design with 12 replicates per treatment. Replacing FM with SBM and PBM in broiler diets improved growth performance and reduced total feed cost per kg of gain. In study 2, seven experimental treatments, 1) 0 d VP, 2) 30 d VTMP, 3) 30 d VP, 4) 60 d VTMP, 5) 60 d VP, 6) 90 d VTMP and 7) 90 d VP, were stored for 0, 30, 60 and 90 days, respectively in an environmentally controlled chamber at 29.4°C and 75%. Samples of treatments were analyzed, and loss of vitamin activity was calculated after storage. Treatments were added to broiler diets to determine the effect of loss of vitamin activity on broiler performance. Dietary treatments were set up as randomized complete block design in four batteries. Storing vitamins with trace minerals for 90 days increased loss of vitamin activity as compared to when stored as vitamin premix. Loss of vitamin activity did not significantly affect overall broiler performance, bone strength and ash. In study 3, Exp. 1 was a 3 × 3 × 4 factorial with corn particles size (400, 600 and 800 μm), method of analysis (laboratory, unground and ground) and diet (SD, SFD, SFB and SB). Diets were formulated to contain 20% crude protein. Subsamples were ground through a 0.5 mm sieve. Crude protein contents of ground and unground samples were analyzed using the Foss DS2500 NIRS (Model Foss DS2500 Monochromator, Foss NIRSystems, Laurel, MD) and compared to laboratory results from wet chemistry analysis. Interaction (P≤0.05) was observed between diet and method and particle size and method, but similar (P≥0.05) crude protein was observed for particle size. Diets and particle sizes were significantly different (P≤0.05) as unground samples but no differences (P≥0.05) were observed when ground and analyzed using the NIRS or wet chemistry. Exp. 2 was a 3 ×2 factorial with method of analysis (laboratory, unground and ground) and feed form (mash and pellet). Diets were formulated to contain 20% crude protein and manufactured with 600 μm corn particle size. Portions of diets were pelleted using a pellet mill and cooled. Ground and unground mash and pellets were analyzed as in Exp. 1. Interaction was found (P≤0.05) between feed form and method of analysis. Feed form and method of analysis significantly (P≤0.05) affected crude protein prediction from the NIRS. Crude protein content of ground mash and pellets were similar (P≥0.05) to that of laboratory results. Generally, analyzing finished feed samples in the unground form with the NIRS while using standard calibrations yielded less accurate predictions for crude protein, but samples in the ground form yielded similar (P≥0.05) results when analyzed with either the NIRS or wet chemistry.
150

Avaliação e comparação de imagens LISS-III/ResourceSat-1 e TM/Landsat 5 para estimar volume de madeira de um plantio de Pinus elliottii

Berra, Elias Fernando January 2013 (has links)
O objetivo deste trabalho foi estimar o volume de madeira de um povoamento jovem de Pinus elliottii, localizado no litoral sudeste do Rio Grande do Sul, com imagens dos sensores LISS-III/ResourceSat-1 e TM/Landsat 5, comparando o desempenho destes para tal. Obtiveram-se imagens de setembro de 2010, mês coincidente com o inventário florestal feito na área de estudo. Os valores de reflectância espectral de superfície foram recuperados das imagens originais. Após o georreferenciamento, dos pixels coincidentes com a localização das unidades amostrais do inventário florestal foram extraídos os valores das reflectâncias nas quatro bandas espectrais equivalentes aos dois sensores, cujas respostas foram comparadas. Além das bandas espectrais foram utilizados os índices de vegetação (IV’s) SR, NDVI, SAVI, MVI e GNDVI. Também, foi proposto o ajuste destes IV’s originais pela idade do povoamento, os quais foram identificados por SR_i, NDVI_i, MVI_i e GNDVI_i. A aplicação do logaritmo nas bandas espectrais melhorou os valores dos coeficientes de correlação linear (r), à exceção do IVP, retornando valores entre 0,69 (IVP) a 0,83 (Verde) para o LISS-III e entre 0,68 (Vermelho) a 0,79 (IVM) para o TM; Com os IV’s o logaritmo melhorou os valores de r somente para os IV’s originais, retornando valores de r entre 0,77 (NDVI) a 0,84 (GNDVI) com o LISS-III e entre 0,73 (NDVI) a 0,82 (MVI) para o TM. Com os IV’s ajustados pela idade do povoamento a logaritimização não se mostrou necessária para melhorar a associação linear, retornando valores de r entre 0,79 (NDVI_i) a 0,82 (MVI_i) com o LISS-III e entre 0,74 (SR_i) a 0,80 (MVI_i) com o TM. Além disso, o ajuste pela idade aumentou o intervalo dinâmico dos IV’s ajustados, e, aparentemente, aumentou a sensibilidade nos povoamentos de maior volume. Diferenças significativas na associação linear entre os dados espectrais do TM e LISS-III com o volume só foram encontradas na banda equivalente do verde. Com dados TM, a equação melhor ajustada explicou 68% da variabilidade do volume; com dados LISS-III a equação explicou 72% da variabilidade. Estas equações geraram dois mapas de volume de madeira, onde as médias das estimativas obtidas com LISS-III estiveram dentro do intervalo de confiança da média do inventário florestal em 70% dos talhões considerados; para o TM a coincidência foi de 65% dos talhões. Conclui-se que os sensores LISS-III e TM apresentam alta similaridade e que a metodologia empregada pode ser utilizada para auxiliar no inventário florestal dos povoamentos jovens de P. elliottii na área de estudo principalmente pelo fato das estimativas obtidas pelas imagens cobrirem todo o talhão, ao passo que a amostragem do inventário florestal contempla menos de 2% da área. / The aim of this work was to estimate the wood volume of a young stand of Pinus elliottii, located on the southeastern coast of the state of Rio Grande do Sul, by imagery from LISS-III/ResourceSat-1 and TM/Landsat 5 sensors, comparing their performance for such. Images were obtained on September 2010, the month coincident with the forest inventory made in the study area. The surface spectral reflectance values were retrieved from the original images. After the georeferencing, the sampling units location from the forest inventory were used to select the pixels to extract the reflectance values on the four spectral bands equivalents for the two sensors, which answers were compared. In addition to the bands were used the Vegetation Indices (VI’s) SR, NDVI, SAVI, MVI and GNDVI. Also proposed was the adjusting of these original VI’s by the stand age, which ones were identified by SR_i, NDVI_i, MVI_i and GNDVI_i. The application of logarithm in the spectral bands improved the r values, with exception to NIR, achieving values between 0.69 (NIR) and 0.83 (Green) for LISS-III and between 0.68 (Red) and 0.79 (SWIR) for TM; With the VI’s, the logarithm improved the r values only for the original VI’s, returning r values from 0.77 (NDVI) to 0.84 (GNDVI) with LISS-III and r values from 0.73 (NDVI) to 0.82 (MVI) for TM. With the VI’s adjusted by stand age the logarithm was not necessary to improve the linear association, returning r values from 0.79 (NDVI_i) to 0.82 (MVI_i) with LISS-III and r values from 0.74 (SR_i) to 0.80 (MVI_i) with TM. Moreover, adjusting by age increased the dynamic range of the VI’s adjusted, and apparently increased the sensitivity in stands with larger volume. Significant differences in the linear association between TM and LISS-III spectral data with volume were just found on the green equivalent band. With TM data, the best fitted model explained 68% of the volume variability; with LISS-III data the model explained 72% of the variability. These models generated two wood volume maps, where the average of the estimates achieved with LISS-III were within the confidence level of the average from the forest inventory on 70% of the compartments considered; for TM the coincidence was on 65% of the compartments. It is conclude that the sensors LISS-III and TM presented high similarity and the methodology applied can be used to aid in forest inventory of young stands of P. elliottii in the study area mainly because the estimates obtained by the images cover the entire compartment, while the forest inventory sampling contemplates less than 2% of the area.

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