Compression may refer to:
Physical science
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Compression (physics)
In mechanics, compression is the application of balanced inward ("pushing") forces to different points on a material or structure, that is, forces with no net sum or torque directed so as to reduce its size in one or more directions.Ferdinand ...
, size reduction due to forces
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Compression member
Compression members are structural elements that are pushed together or carry a load; more technically, they are subjected only to axial compressive forces. That is, the loads are applied on the longitudinal axis through the centroid of the memb ...
, a structural element such as a column
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Compressibility
In thermodynamics and fluid mechanics, the compressibility (also known as the coefficient of compressibility or, if the temperature is held constant, the isothermal compressibility) is a measure of the instantaneous relative volume change of a ...
, susceptibility to compression
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Gas compression
A compressor is a mechanical device that increases the pressure of a gas by reducing its volume. An air compressor is a specific type of gas compressor.
Compressors are similar to pumps: both increase the pressure on a fluid and both can trans ...
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Compression ratio
The compression ratio is the ratio between the volume of the cylinder and combustion chamber in an internal combustion engine at their maximum and minimum values.
A fundamental specification for such engines, it is measured two ways: the stat ...
, of a combustion engine
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Compression (geology)
In geology, the term compression refers to a set of stress directed toward the center of a rock mass. Compressive strength refers to the maximum compressive stress that can be applied to a material before failure occurs. When the maximum compre ...
*Compression or
compressive strength
In mechanics, compressive strength or compression strength is the capacity of a material or structure to withstand loads tending to reduce size (as opposed to tensile strength which withstands loads tending to elongate). In other words, compre ...
Information science
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Data compression
In information theory, data compression, source coding, or bit-rate reduction is the process of encoding information using fewer bits than the original representation. Any particular compression is either lossy or lossless. Lossless compressi ...
, reducing the data required for information
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Audio compression (data)
Audio most commonly refers to sound, as it is transmitted in signal form. It may also refer to:
Sound
*Audio signal, an electrical representation of sound
* Audio frequency, a frequency in the audio spectrum
* Digital audio, representation of sou ...
, reducing the data required for audio
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Bandwidth compression
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Compression artifact
A compression artifact (or artefact) is a noticeable distortion of media (including images, audio, and video) caused by the application of lossy compression. Lossy data compression involves discarding some of the media's data so that it be ...
, defect in data due to compression
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Image compression
Image compression is a type of data compression applied to digital images, to reduce their cost for storage or transmission. Algorithms may take advantage of visual perception and the statistical properties of image data to provide superior re ...
, of digital images
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Video compression
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One-way compression function In cryptography, a one-way compression function is a function that transforms two fixed-length inputs into a fixed-length output. The transformation is "one-way", meaning that it is difficult given a particular output to compute inputs which compre ...
, a cryptographic primitive
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Dynamic range compression
Dynamic range compression (DRC) or simply compression is an audio signal processing operation that reduces the volume of loud sounds or amplifies quiet sounds, thus reducing or ''compressing'' an audio signal's dynamic range. Compression is ...
, reducing audio dynamic range
Medicine
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Brain compression, a medical condition
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Compression bandage
*Pressing on the lower abdominal area in an
intravenous pyelogram
Pyelogram (or pyelography or urography) is a form of imaging of the renal pelvis and ureter.
Types include:
* Intravenous pyelogram – In which a contrast solution is introduced through a vein into the circulatory system.
* Retrograde pyelogram ...
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Cold compression therapy, for minor injuries
Other
*Amplifier
gain compression
Gain compression is a reduction in ''differential'' or ''slope'' gain caused by nonlinearity of the transfer function of the amplifying device. This nonlinearity may be caused by heat due to power dissipation or by overdriving the active dev ...
, due to nonlinearity
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Compression (dance), several techniques
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Compression (functional analysis) In functional analysis, the compression of a linear operator ''T'' on a Hilbert space to a subspace ''K'' is the operator
:P_K T \vert_K : K \rightarrow K ,
where P_K : H \rightarrow K is the orthogonal projection onto ''K''. This is a natural ...
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Compression (phonetics), running syllables together
See also
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Compaction (disambiguation)
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Compress
compress is a Unix shell compression program based on the LZW compression algorithm. Compared to more modern compression utilities such as gzip and bzip2, compress performs faster and with less memory usage, at the cost of a significantly l ...
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Compression garment
Compression garments are pieces of clothing that fit tightly around the skin. In medical contexts, compression garments provide support for people who have to stand for long periods or have poor circulation. These come in varying degrees of com ...
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Compressor (disambiguation)
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Decompression (disambiguation) Decompression has several meanings, some of which are covered by several articles:
* Data decompression, the action of reversing data compression
* Decompression (physics), the release of pressure and the opposition of physical compression
** Decom ...
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Expansion (disambiguation)
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