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Decibel
 
(dB) A customary logarithmic measure most commonly used (in various ways) for measuring sound. If one sound is 1 bel (10 decibel) 'louder' than another, this means the louder sound is 10 times louder than the fainter one. A difference of 20 decibel corresponds to an increase of 10 x 10 or 100 times in intensity.
For sound pressure (the pressure exerted by the sound waves) 0 decibel equals 20 micropascal (μPa), and for sound power 0 decibel sometimes equals 1 picowatt.

See also Phon and Acoustic Noise.
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Decimation
 
Decimation is the reduction of data at the digitized signal. Fewer samples are used to represent the signal. Decimation can be realized by decimation in frequency or decimation in time.
The opposite process is called interpolation, more samples are added.
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Further Reading:
  Basics:
The Scientist and Engineer's Guide to Digital Signal Processing
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DecouplingInfoSheet: - Artifacts -
Case Studies, 
Reduction Index, 
etc.
 
1) The specific irradiation designed to remove the multiple structure in a particular resonance due to spin spin coupling with other nuclei;
2) The preventing of the interaction by mutual inductive coupling of two (or more) resonant RF coils, e.g. by detuning coils not in use at a particular point in time. Decoupling can take the form of active decoupling where an externally controlled switching circuit is used to detune the non-selected coils or passive decoupling where RF energy from the transmitter pulse is used to switch diodes to detune the appropriate coil.
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Further Reading:
  Basics:
A Half-Volume Coil for Efficient Proton Decoupling in Humans at 4 Tesla
1997   by www.cmrr.umn.edu    
Delay Alternating with Nutation for Tailored ExcitationInfoSheet: - Sequences -
Intro, Overview, 
Types of, 
etc.MRI Resource Directory:
 - Sequences -
 
(DANTE) A technique used to place a saturation band over e.g. the myocardium. This technique includes spatial modulation of magnetization complementary and delays alternating with nutations for tailored excitation, followed by the application of a cine or real-time imaging. Because the saturated magnetization pattern moves with the atoms of the tissue, the cardiac motion shows up as deformations in the grid pattern in the resulting imaging sequence.
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Demodulator
 
Another term for detector, by analogy to broadcast radio receivers. Other terms used for devices of this type include modulators, phase sensitive detector and mixers.
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MRI is trending to low field magnets :
reduced costs will lead to this change 
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