Definitions of Attenuation on the Web:

The process of weakening or reducing the amplitude of a sonar signal. It is caused by numerous factors, including material dispersion, beam spreading and absorption. The attenuation of a sonar signal makes its detection more difficult. Reflected signals from far away are sometimes attenuated to such a degree that system noise in the sonar receiver electronics can be a problem.www.instituteformarineacoustics.org/SonarPrimer/data/gloss_6c.htm

Loss of signal power. Attenuation is typically measured in decibels per kilometer (dB/km) at a specific wavelength.www.seaconbrantner.com/Terminology/terminology.htm

The loss in power of electromagnetic signals between transmission and reception points.www.spidersat.net/glossary/glossary_a.htm

The decrease in the power of a signal, light beam, or light wave. Measured in decibels. Opposite of gain.www.kraycabling.com/technical_info/glossary.htm

A weakening (of meaning). Lat. teneo 'to hold' weakens to become the general verb of possession tener in Spanish.www.cus.cam.ac.uk/~cjp16/spanish/linggloss.htm

The dissipation of the power of a transmitted signal as it travels over a wire.www.nationaldatamux.com/glossary.htm

Reduction of sound pressure level as in "hearing protector attenuation"www.e-a-r.info/_glossaryofterms.htm

In physics, any process in which the flux density (or power, amplitude, intensity, illuminance, etc.) of a "parallel beam" of energy decreases with increasing distance from the source. Attenuation is always due to the action of the transmitting medium itself, mainly by absorption and scattering. In meteorological optics, the attenuation of light is termed extinction.www.novalynx.com/glossary.html

The reduction in intensity of a beam of X- or gamma radiation during its passage through matter caused by absorption and scattering.www.ndt.net/article/az/rt/rt.htm

The reduction of noise.www.dot.ca.gov/dist4/sfobb/appendixD.html

A decrease in signal magnitude between two points, or between two frequencies. The reciprocal of gain.www.geomechanics.com/dspapp.cfm

A measure of the drop in specific gravity which takes place as the wort ferments. One of the characteristics of yeasts which brewers concern themselves with is the average attenuation, which can range from yeast to yeast. 65% would be a low attenuation, while 85% would be very high. No brewer's yeast ferments all the sugars in the beer. Selecting a yeast strain with a certain average attenuation is another tool the brewer has to control the body of the beer.www.bodensatz.com/staticpages/index.php

The process by which a compound is reduced in concentration over time through adsorption, degradation, dilution and/or transformation, usually by natural processes.www.state.nj.us/dep/srp/publications/site_status/1998/html/glossary.htm

is the decrease in signal strength as the signal travels through any medium such as a cable.www.homedirector.com/glossary.php3

Any process in which the flux density (power) of a beam of energy is dissipated.www.srh.weather.gov/srh/jetstream/append/glossary_a.htm

Blocking or modulation of the excitation light intensity can be accomplished with a series of filters that transmit increasing percentages of the incident light or with an acousto-optic tunable filter (see AOTF).www.nature.com/focus/cellbioimaging/glossary/

The total light lost from a beam of light propagating through water. These losses are due to scattering from suspended materials and the molecular scattering of the water itself, and to particulate and dissolved materials and the water itself absorbing the light. The amount of attenuation is primarily dependent upon the wavelength of the propagated light, the concentration of suspended materials and the concentration and composition of both particulate and dissolved absorbing materials.www.wetlabs.com/glossary.htm

A reduction in amplitude or energy caused by the physical characteristics of the transmitting media or system.www.sensoft.ca/services/glossary.html

Decrease in intensity usually of such wave phenomena as light or sound.history.nasa.gov/EP-95/glossary.htm

Loss of signal power between points. In optical cables, attenuation is a ratio of input power vs. output power, measured in decibels per unit length, usually dB/km.logicalpackets.com/Network%20Learning/fiber_optic_glossary.htm

a decrease in the energy of light due to absorption and scattering in the water columncoexploration.org/bbsr/classroombats/html/body_glossary.html

the reduction in the peak of a hydrograph as it moves downstream, resulting in a more broad, flat hydrograph.www.dnr.state.mn.us/water/hydroterms.html

The amount of light loss experienced in an optical fiber or optical media as a function of length. For optical fiber it is usually expressed in dB (decibels) per kilometer (km). See Transmission.www.polymicro.com/techsupport/techsupport_glossary.htm

A general term indicating a decrease in power from one point to another. In optical fibers, it is measured in decibels per kilometer at a specified wavelength.www.point-source.com/glossary.asp

Loss of power. Attenuation is usually measured in dB loss per length of cable (ex. 31.0 dB/100Ft.). Attenuation increases as frequency increases.www.mycableshop.com/techarticles/Coaxial.htm

weakening in force or intensity; "attenuation in the volume of the sound" the property of something that has been weakened or reduced in thickness or density

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