Results 311 to 320 of about 278,573 (333)

Effect of Color Temperature on Apparent Brightness

Journal of the Optical Society of America, 1954
Two screens viewed side by side were illuminated by radiations approximating those of blackbodies of different color temperatures and matched in brightness at photopic levels. A group of 73 observers found that less light of the higher color temperature was needed to produce equality of brightness than would be required by the CIE normal observer.
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High Brightness Temperatures in IDV Sources

Chinese Journal of Astronomy and Astrophysics, 2006
High brightness temperatures are a characteristic feature of IntraDay Variability (IDV) of extragalactic radio sources. Recent studies of the polarization properties of some IDV sources (e.g., 1150+812, PKS 0405-385 and 0716+714) have shown that these sources harbor several compact IDV components with angular sizes of ∼10-30µas and very high ...
Shan-Jie Qian, T. P Krichbaum, A Witzel, J. A Zensus, Xi-Zhen Zhang   +4 more
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Average brightness temperature of antenna aperture

Journal of Electronics (China), 1997
This paper presented an idea for the average brightness temperature of lossless antenna aperture, gave its expression for matched and dismatched noise source. This expression showed that the average brightness temperature of antenna aperture related with three factors: the noise temperature of noise source, the reflection coefficient of noise source ...
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Brightness Temperature from Very Lossy Medium

2018 USNC-URSI Radio Science Meeting (Joint with AP-S Symposium), 2018
The brightness temperature from moistured soil with a flat surface is computed by defining near-field bistatic transmission coefficients (BTCs) and modifying the Planck's law for lossy medium. The efficacy of the proposed methods are verified by simulations and comparison with literatures.
Zhi-Hong Lai, Jean-Fu Kiang
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Lunar Brightness Temperature Measurement with CHIME

2021
Half a century after measurement of the lunar brightness temperature for preparations of the moon landing, Canadian Hydrogen Intensity Mapping Experiment (CHIME) provides improved instrumentation and a more sophisticated method for the same measurement.
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Brightness, Emittance and Temperature

1988
During the past fifty years there has been a spectacular growth in the number of applications for particle beams. The various practical requirements scan orders of magnitude in energy, current, and particle mass, from electrons to uranium ions. The behaviour of some of these beams, especially when self-fields are large and interaction with walls or ...
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Microwave brightness temperature of snow: Observations and simulations

2016 IEEE International Geoscience and Remote Sensing Symposium (IGARSS), 2016
The brightness temperature of snow-covered terrain was monitored from January through April 1985 using tower-based radiometers operating at 1, 16.5, and 37 GHz (vertical and horizontal polarization) in southern Finland. Ground truth data on snow, soil and weather were collected. Layered dielectric, extinction and wetness information on snow at the test
Lemmetyinen, Juha, Hallikainen, Martti
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Bright and Semi-Bright Nickel Plating from Low Metal/Low Temperature Solutions

Transactions of the IMF, 1977
SummaryThe comparison is made between recently developed low concentration, low temperature bright nickel and semi-bright nickel plating processes and conventional bright nickel and semi-bright nickel processes in respect to the physical properties of the deposits, stress, ductility, levelling etc, and the tolerance of the solutions to impurities ...
E. A. Baker, S. Hemsley, J. R. House
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Brightness temperature emitted by layered media with nonuniform temperature profile

International Journal of Infrared and Millimeter Waves, 1996
Based on the transmission-line theory, this paper describes a new procedure to calculate the radiation from layered media with nonuniform temperature profile. The result is compared with those obtained through the incoherent method and the analysis of the electromagnetic fields.
Ying Lu, Zuying Zhang, Wei Guo
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Colour Temperature and Brightness of Moonlight

Nature, 1923
OUR more complete knowledge of full or black-body radiation embodied in Planck's law makes it possible to speak of the temperature of radiation as well as the temperature of radiating bodies. Thus, the temperature of any visible radiation is the temperature to which a black body must be raised to emit light as nearly as possible of the same integral ...
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