- ATA
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- Abbreviation for American Trucking Association -- a national federation of independent and autonomous truck carrier conferences and state trucking associations. Includes Regular Common Carrier Conference, National Tank Truck Carriers Conference.
- Abbreviation for Air Transport Association
- ATB
-
All-Terrain Bike
- Abbreviation for all-terrain bike. Sometimes called MTB (mountain bike), but ATB is the preferred Abbreviation.
- Abbreviation for aeration test burner
- ATC
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- Abbreviation for automatic temperature control.
- Abbreviation for air-traffic control
- Abbreviation for Automatic Traction Control -- an optional feature based on ABS which prevents spinning of the drive wheels under power on slippery surfaces by braking individual wheels and/or reducing engine throttle. Also called ASR, an Abbreviation sometimes loosely translated from the German as anti-spin regulation.
- ATE
- Abbreviation for Automatic test equipment
- ATF
- Abbreviation for Automatic Transmission Fluid
- ATM
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- Abbreviation for Standard atmosphere
- Abbreviation for Actuator Test Mode
- Atmospheric acoustics
- The study of how sound is transmitted in the air at different altitudes, weather, humidity, and atmospheric pressure.
- Atmospheric corrosion
- The gradual eating away of metal caused by the action of the gaseous elements in the atmosphere including oxygen's rusting action on iron and the effects of acid rain
- Atmospheric crude oil distillation
- The refining process of separating crude oil components at atmospheric pressure by heating to temperatures of about 316°C to 400°C (depending on the nature of the crude oil and desired products) and subsequent condensing of the fractions by cooling.
- Atmospheric distillation unit
- The primary distillation unit that processes crude oil (including mixtures of other hydrocarbons) at approximately atmospheric conditions. It includes a pipe still for vaporizing the crude oil and a fractionation tower for separating the vaporized hydrocarbon components in the crude oil into fractions with different boiling ranges. This is done by continuously vaporizing and condensing the components to separate higher oiling point material. The selected boiling ranges are set by the processing scheme, the properties of the crude oil, and the product specifications.
- Atmospheric dust spot efficiency
- A measurement of a device's ability to remove atmospheric air from test air
- Atmospheric engine
- Earliest form of practical steam engine, in which a partial vacuum created by stem condensation allowed atmospheric pressure to drive down the piston.
- Atmospheric gas-burner system
- A natural-draft burner injector, in which the momentum of the gas passing into the injector throat inspirates part of the air required for combustion.
- Atmospheric pressure
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- The force due to atmosphere per unit area. Atmospheric pressure at sea level is 14.7 psi absolute; it decreases as altitude increases.
- The pressure of the weight of air and water vapor on the surface of the earth at sea level, namely 760 mm mercury column or 101.3 kPa.
- Atmospheric pressure sensor
- A detection device that measures atmospheric pressure. This allows the computer to change engine output in relation to atmospheric pressure and engine vacuum.
- Atmospheric-suspended power chamber
- A booster power chamber with atmospheric pressure on both sides of its diaphragm when the brakes are not applied.
- Atom
- The basis of all matter. It consists of a nucleus made up of protons and neutrons, and one or more orbiting electrons.
- Atomization characteristics
- The ability of an oil to be broken up into a fine spray by some mechanical means.
- Atomize
- The process of changing liquid to minute particles or a fine spray. The extent to which a spray gun breaks up paint into a fine mist, fog, or spray.
- Atomized
- Tiny particles of a solid or liquid substance (fuel or paint) mixed with air, making a fine mist.
- Atomized powder
- A powder produced by the dispersion of molten metal or other material by spraying under conditions such that the material breaks down into powder.
- Atomospherics
- British term for strays
- ATR
- Abbreviation for Attenuated total reflection
- A-Train
- Colloquial term for a truck tractor pulling more than one trailer connected by A-dollies
- Atramentizing
- A corrosion protection process in which steel is coated with phosphate using a zinc phosphate solution at 90°C.
- ATS
- Abbreviation for Air temperature sensor
- Attachment
- A fitting or accessory to be used in conjunction with a tool, such as a grinding disc for use with an electric drill.
- Attenuated total reflection
- Spectroscopic method of analyzing thin films on reflective substrates, esp. using infrared radiation.
- Attenuation
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- A reduction of noise or emission.
- General term for reduction in magnitude, amplitude, or intensity of a physical quantity, arising from absorption, scattering, or geometrical dispersion. The latter, arising from diminution by the inverse square law, is not generally considered as attenuation proper.
- Attenuation coefficient
- The coefficient which expresses energy losses of electromagnetic radiation due to both absorption and scattering in a medium. Relevant to narrow beam conditions. Also called total absorption coefficient
- Attenuation compensation
- The use of networks to correct for frequency-dependent attenuation, e.g., in transmission lines.
- Attenuation constant
- The real part of α in the relationship ρ=ρe- αx, where ρ is a physical quantity, such as the amplitude of a wave propagating along a transmission path, and x is the distance along the path. The imaginary part of α is known as the phase constant. More simply, but less commonly defined by μ = αλ where μ is the attenuation and λ is wavelength, i.e., α is the attenuation per wavelength distance of propagation. See
- Attenuation distortion
- Distortion of a complex waveform resulting from the differing attenuation of each separate frequency component in the signal. This form of distortion is difficult to avoid, e.g., in transmission lines.
- Attenuator
- An arrangement of fixed or variable resistive elements designed to reduce the strength of any signal (audio- or radio-frequency) without reducing appreciable distortion. Attenuators also incorporate impedance matching to the transmission lines or circuits to which they are connected, regardless of the attenuation they introduce. For lower frequency applications they may be simply variable or fixed resistances, for high frequencies they may be pieces of resistive material, introduced into transmission lines, stripline, or waveguide. Fixed attenuators are sometimes referred to as pad.
- Attitude
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- The construction of a vehicle which gives the appearance of a particular characteristic which may be aggressive, intimidating, playful, cheerful, etc.
- The overall relationship of a vehicle to the ground
- Of an aircraft in flight, the angle made by its axes with the relative airflow; the aspect is the angle made by its axes with the ground when the aircraft is on the ground.
- Attitude indicator
- A gyro horizon which indicates the true attitude of the aircraft in pitch and roll throughout 360° about these axes.
- Attracted-disk electrometer
- Fundamental instrument in which potential is measured by the attraction between two oppositely charged disks.
- Attrition test
- A test for the determination of the wear-resisting properties of stone, particularly stone for road-making. Pieces of the stone are placed in a closed cylinder, which is then rotated for a given time, after which the loss of weight due to wear is found.