Results 311 to 320 of about 306,957 (330)

Model Diffuse Attenuation Coefficient Profiles

[Proceedings] IGARSS '92 International Geoscience and Remote Sensing Symposium, 2005
Abstract : Light transport through water is controlled by the properties of dissolved substances, particulate matter, and water itself. The rate at which the light field decays can be measured by optical instrumentation and parameterized by the apparent optical property of the water, the diffuse attenuation coefficient, k.
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Study on characteristics of the diffuse attenuation coefficient

2010 The 2nd Conference on Environmental Science and Information Application Technology, 2010
Studying of diffuse attenuation coefficient is the basis for the bathymetry of remote sensing inversion. The research of water attenuation coefficient carried on the use of HR2000 fiber optic spectrometer discovers that the attenuation coefficient at different depths has good spectral features. There are two peaks near the 700nm and 800nm.
Li-fan Chen, Ying Zhang, Zheng-jun Wang
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Attenuation coefficients of Rayleigh and Lg waves

Journal of Seismology, 2010
Analysis of the frequency dependence of the attenuation coefficient leads to significant changes in interpretation of seismic attenuation data. Here, several published surface-wave attenuation studies are revisited from a uniform viewpoint of the temporal attenuation coefficient, denoted by χ. Theoretically, χ( f) is expected to be linear in frequency,
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Reference Materials for the Measurement of Acoustic Attenuation Coefficients

Japanese Journal of Applied Physics, 2011
In this work, we present a reference material for measuring the acoustic attenuation coefficient of biological tissues or tissue-mimicking materials by a transmission method. Accurate measurements by the method require a reference material that has the same acoustic velocity and density as the biological tissue.
Akari Gotow, Tomoji Yoshida, Kouhei Tanaka, Toshio Kondo   +3 more
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Measurement of γ-ray attenuation coefficients

The International Journal of Applied Radiation and Isotopes, 1974
Gamma-ray attenuation coefficients have been determined for aluminum, copper, tin, platinum and lead (elements with Z between 13 and 82) using gamma - rays with energies between 295 and 2440 keV from a sealed Ra-226 source. A lithium-drifted germanium detector was employed without collimation or shielding. The average standard error of the experimental
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Seismic wave attenuation coefficient for soils

The Journal of the Acoustical Society of America, 2000
Several projects over the past years have provided the opportunity to measure the ground propagation properties of seismic waves. Data from a variety of vibration sources and soil types have been summarized in the form of the coefficient of attenuation versus frequency in the ranges 5–250 Hz.
Hooshang Khosrovani, Jose C. Ortega
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Gamma-Ray Attenuation Coefficient Measurements

Physical Review A, 1973
In an earlier paper, published by the author elsewhere, it was shown that for 661.6-keV gamma rays the measurements of gamma -ray attenuation coefficicnts would greatly improve if one uses the counting sequence of Conner et al. together with a new criterion mu t < 1, where mu is the gamma -ray attenuation coefficient and t is the thickness of the ...
B. Sanjeevaiah, S. Gopal
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Gamma-ray attenuation coefficients for germanium

Nuclear Instruments and Methods, 1967
Abstract An interpolation method based on the values listed in NBS-583 for five elements adjacent to germanium was used to determine the gamma-ray attenuation coefficients of germanium. If the region of the atomic numbers, Z, is relatively small and the gamma-ray energy is not too close to the K-shell energies for the elements in this range of Z, the
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The Attenuation Coefficients in CT: A Didactic Review

1980
The density of a structure on a CT image depends on the CT number which in turn is derived from the linear attenuation coefficient (u) according to one of the following equations : $$\frac{{ux - uw}}{{uw}} x 100 x 5 $$ (1) $$\frac{{ux - w}}{{uw}} x 100 x 10 $$ (2) where ux and uw are the attenuation coefficients for a certain ...
M. H. Gado, J. Eichling
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The attenuated Radon transform with complex coefficients

Inverse Problems, 2007
We confirm that the arguments by Natterer (2001 Inverse Problems 17 113–9) can be extended to the attenuated Radon transform with complex-valued coefficients and readily lead to the range condition derived by Novikov (2002 Ark. Math. 40 145–67). We give a simple example to numerically verify the inversion formula in the case of constant imaginary ...
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