Results 201 to 210 of about 844 (236)
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International Journal of Remote Sensing, 1987
A radiative transfer model is used to investigate how the error of spectral hemispherical reflectance data obtained from nadir reflectance values varies with wavelength, solar zenith angle, leaf area index, and leaf orientation distribution. Several techniques employing multiple off-nadir view angles taken in azimuth planes are found to accurately ...
D S Kimes, P J Sellers, David J Diner
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A radiative transfer model is used to investigate how the error of spectral hemispherical reflectance data obtained from nadir reflectance values varies with wavelength, solar zenith angle, leaf area index, and leaf orientation distribution. Several techniques employing multiple off-nadir view angles taken in azimuth planes are found to accurately ...
D S Kimes, P J Sellers, David J Diner
exaly +2 more sources
Method for measurement of the directional/hemispherical reflectance of photovoltaic devices
Optics Communications, 2000A novel method, and the relative apparatus, are described which permit to measure the directional/hemispherical reflectance of a surface at incidence angles h in the interval 0‐90∞. The method, suitable for the characterization of optically homogeneous as well as heterogeneous samples, is named ‘‘diAerencing reflection method’’ as the reflectance of ...
Pasqualino Maddalena
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Remote Sensing of Environment, 1993
Spatial averaging errors which may occur when creating hemispherical reflectance maps for different cover types from direct nadir technique to estimate the hemispherical reflectance are assessed by comparing the results with those obtained with a knowledge-based system called VEG (Kimes et al., 1991, 1992).
D S Kimes, P J Sellers
exaly +2 more sources
Spatial averaging errors which may occur when creating hemispherical reflectance maps for different cover types from direct nadir technique to estimate the hemispherical reflectance are assessed by comparing the results with those obtained with a knowledge-based system called VEG (Kimes et al., 1991, 1992).
D S Kimes, P J Sellers
exaly +2 more sources
Applied Optics, 1994
Measurements of the directional-hemispherical reflectance ρ with the Physikalisch-Technische Bundesanstalt IR sphere reflectometer have been confirmed by calorimetric determination of the absorptance α in the same geometrical conditions (irradiation at 10°, hemispherical reflection).
W, Richter, S M, Sarge, F, Kämmer
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Measurements of the directional-hemispherical reflectance ρ with the Physikalisch-Technische Bundesanstalt IR sphere reflectometer have been confirmed by calorimetric determination of the absorptance α in the same geometrical conditions (irradiation at 10°, hemispherical reflection).
W, Richter, S M, Sarge, F, Kämmer
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Surface length scale contributions to the directional and hemispherical emissivity and reflectivity
Journal of Thermophysics and Heat Transfer, 1995Rigorous electromagnetic scattering solutions, based on the extinction theorem, are used to investigate the surface geometry contributions to the directional and hemispherical emissivity and to the directional hemispherical reflectivity for one-dimensional configured or random rough surfaces with different material properties.
Yongqing Yang, Richard O. Buckius
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Measurement Of Near-Normal/Hemispherical Reflectance And Directional Emittance In The Mid-Infrared
SPIE Proceedings, 1987Based on a FTIR spectrometer a measuring device for the determination of the spectral near-normal/hemispherical reflectance and the spectral directional emittance, respectively, of opaque, diffusely reflecting samples has been built up. The device is mainly used for the measuring of the spectral emittance of low-emitting selective solar absorber ...
K. Gindele, M. Kohl
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Room temperature hemispherical and bi-directional reflectances
11th IEEE International Conference on Advanced Thermal Processing of Semiconductors. RTP 2003, 2004The emissivity of a material is conveniently determined from its reflectance, which is turn can be used to validate optical models for estimating emissivity at high temperatures. The Optical Technology Division of the National Institute of Standards and Technology maintains the national reference instruments for measurements of reflectance.
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Optical Engineering, 2005
Experimental data are presented on the bidirectional reflectance distribution function and 8-deg directional-hemispherical reflectance measurements of a Martian regolith simulant, JSC Mars-1. The scatterometer located in the National Aeronautics and Space Administration's Goddard Space Flight Center Diffuser Calibration Facility was used for the ...
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Experimental data are presented on the bidirectional reflectance distribution function and 8-deg directional-hemispherical reflectance measurements of a Martian regolith simulant, JSC Mars-1. The scatterometer located in the National Aeronautics and Space Administration's Goddard Space Flight Center Diffuser Calibration Facility was used for the ...
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Solar Energy Materials, 1987
Abstract Measurements are presented of the bidirectional spectral reflectance and directional-hemispherical spectral reflectance of Nextel-2010 black velvet, Solarcoat-50, Cusorb, Skysorb, Maxorb and Solarcoat-100 at wavelengths of 633 nm and 1152 nm.
Ajit A. De Silva, Barrie W. Jones
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Abstract Measurements are presented of the bidirectional spectral reflectance and directional-hemispherical spectral reflectance of Nextel-2010 black velvet, Solarcoat-50, Cusorb, Skysorb, Maxorb and Solarcoat-100 at wavelengths of 633 nm and 1152 nm.
Ajit A. De Silva, Barrie W. Jones
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