Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 20 of 29 for “"BRDF"”.
-
A Numerical Study of the Sensitivity of Cloudy-Scene Bidirectional Reflectivity Distribution Functions to Variations in Cloud Parameters
… reflectivity distribution function (BRDF) to variations in cloud parameters. The BRDF is a remote sensing tool used to predict the flux reflected from a given earth scene from a satellite-based measurement of the reflected intensity. The BRDF is necessary in order to account for the …
-
Bidirectional Reflectance Measurements of Low-Reflectivity Optical Coating Z302
… bidirectional reflectance distribution function (BRDF) is an indispensable parameter in the optical characterization of such coatings. The current effort involves investigation of the BRDF of the commercial black coating Aeroglaze® Z302. An automated goniometer reflectometer has been designed, …
-
Baffle material characterization for Advanced LIGO
… Bidirectional Reflectance Distribution Function (BRDF) of a material. The arrangement was used to measure the BRDF for black welder's glass, the prime candidate material for baffles in Advanced LIGO. I found that black glass has a BRDF on the order of 10-, putting it within sensitivity …
-
Design and evaluation of distributed spacecraft missions for multi-angular Earth observation
… Bidirectional Reflectance-Distribution Function (BRDF), which describes the directional and spectral variation of reflectance of an optically thick surface element at any time instant. Airborne instruments are the gold standard for BRDF estimation (e.g. Cloud Absorption Radiometer/CAR). They can …
-
Ground-based hyperspectral and spectro-directional reflectance characterization of Arctic tundra vegetation communities : field spectroscopy and field spectro-goniometry of Siberian and Alaskan tundra in preparation of the EnMAP satellite mission
… bidirectional reflectance distribution function (BRDF). This effect can cause significant changes in the measured surface reflectance depending on solar illumination and sensor viewing geometries. The aim of this thesis is the hyperspectral and spectro-directional reflectance characterization of …
-
A data-driven reflectance model
… reflectance distribution functions (BRDFs) based on acquired reflectance data. Instead of using analytic reflectance models, each BRDF is represented as a dense set of measurements. This representation allows interpolation and extrapolation in the space of acquired BRDFs to create new …
-
Manufacturing and Characterization of Gold-Black and Prediction and Measurement of its Directional Spectral Absorptivity
… bidirectional reflectance distribution function (BRDF) measurements for two thicknesses (~4 μm and ~8 μm) of gold-black laid down on a gold mirror substrate are reported in the visible (532 nm) and near-infrared (800 and 850 nm) for p- and s-polarizations. The investigation is then extended to a …
-
Local illumination models from surface geometry microform
… of cloth and develop a method to derive the BRDF (Bidirectional Reflectance-Distribution Function) of this model from the underlying surface geometry, taking into account the blocking and shadowing phenomena at the small scale. Sample images of cloth generated with this BRDF look highly …
-
A population Monte Carlo approach to estimating parametric bidirectional reflectance distribution functions through Markov random field parameter estimation
… bidirectional reflectance distribution function (BRDF) for an object surface. The method uses a novel Markov Random Field (MRF) formulation on triplets of corner vertex nodes to model the probability of sets of reflectance parameters for arbitrary reflectance models, given probabilistic surface …
-
Generative representations of 2D and 3D visual content: semantics, geometry, and appearance
… modelling, presenting M 3 ashy, a multimodal BRDF synthesis framework based on hyperdiffusion, and PBNBRDF, a physically based neural BRDF representation that enforces Helmholtz reciprocity and energy conservation for realistic material reconstruction and generation. Together, these …
-
Importance Resampling for Global Illumination
… We also suggest using RIS as a default BRDF sampling technique.
-
Predicting Surface Scatter Using A Linear Systems Formulation Of Non-paraxial Scalar Diffraction
… angles. In addition, they provide an improved BRDF (Bidirectional Reflectance Distribution Function) model, particularly for the smooth surface inverse scattering problem of determining surface power spectral density (PSD) curves from BRDF measurements.
-
Sampling Methods in Ray-Based Global Illumination
… sampling} to sample the product of the BRDF function and a large light source such as an environment map. We then extend this method to include all three terms of the direct lighting equation, sampling the triple product of the BRDF, lighting and visibility. We show that the new sampling …
-
Analyse de sensibilité des indices de végétation au-dessus d'un couvert forestier de sapin: Étude comparative à partir des données de simulation entre MODIS-EOS, VEGETATION-SPOT and AVHRR-NOAA
… and linearity) and external disturbing factors (BRDF and atmosphere) to covers starting from the data of simulation. The second point makes it possible to compare for the first time the potential of three spectral resolutions different (fine, average and broad) from sensors MODIS-EOS, …
-
Bidirectional Distribution Reflection Function of Algodones Dunes
… by the Linear Mixed Model approach for different BRDF runs of the same sample, and for different sand samples, were compared to determine whether the spectral response of sand samples from the Algodones Dunes is the same or not. Based on the data modeled by the Linear Mixed Model, it was found …
-
Classical Element Feedback Control for Spacecraft Orbital Maneuvers
… keeping maneuvers for NASA-Goddard's Leonardo-BRDF formation, and coupled orbit, and attitude maneuvers for HokieSat, a spacecraft designed, and built by students at Virginia Tech to fly in the Ionospheric Observation Nanosatellite Formation (ION-F). To provide target orbit states for feedback …
-
LumiModeling: A Gaussian Splatting-Based Tool for Recreating Dynamic Material and Lighting Interaction in Architecture
… is augmented with physical parameters, including BRDF, surface normals, and incident lighting. The Stata Center dataset is used to test the relighting of GS. A user study involving architecture professionals reveals that perceptual focus shifts from geometry to materiality and lighting as visual …
-
REMOTELY MAPPING SURFACE ROUGHNESS ON ALLUVIAL FANS: AN APPROACH FOR UNDERSTANDING DEPOSITIONAL PROCESSES
… Bidirectional Reflectance Distribution Function (BRDF) describes changes in reflectance based on changes in the angle of irradiance and radiation-scattering effects of a surface. Using Landsat 7 satellite imagery, the changes in observed surface reflectance, resulting from seasonal changes in the …
-
Data-efficient Neural Appearance Manipulations
… fine detail editing in photographs, and (2) HyperBRDF, a bidirectional reflectance distribution function (BRDF) representation that enables sparse reconstruction, compression, and editing. By leveraging the known or learned priors that include problem-specific information, the proposed methods …
-
Land Surface Phenology of North American Mountain Environments Using the Terra Moderate Resolution Imaging Spectroradiometer
… 16-day products, Vegetation Index and Nadir BRDF Adjusted Reflectance, to assess start of season (SOS) for the 2007 calendar year. Independent data for elevation, slope, aspect, solar radiation, and temperature as well as longitude and latitude were then related to the SOS output. Based on …
Page 1 of 2