Spectral density — In statistical signal processing and physics, the spectral density, power spectral density (PSD), or energy spectral density (ESD), is a positive real function of a frequency variable associated with a stationary stochastic process, or a… … Wikipedia
Spectral efficiency — Spectral efficiency, spectrum efficiency or bandwidth efficiency refers to the information rate that can be transmitted over a given bandwidth in a specific communication system. It is a measure of how efficiently a limited frequency spectrum is… … Wikipedia
Bispectral index — A Bispectral index (BIS) monitor is a neurophysiological monitoring device which continually analyses a patient s electroencephalograms during general anaesthesia to assess the level of consciousness during anaesthesia. The depth of anaesthesia… … Wikipedia
Dream — For other uses, see Dream (disambiguation). The Knight s Dream , 1655, by Antonio de Pereda Dreams are successions of images, ideas, emotions, and sensations that occur involuntarily in the mind during certain stages of sleep … Wikipedia
SEF — may mean: * Science Education Foundation * Search Engine Friendly, a way to format URLs for SEO * Sicher/Einzelfeuer/Feuerstoß, a trigger grouping used on Heckler Koch guns such as the MP5 * Sinfonia Educational Foundation * Straits Exchange… … Wikipedia
SEF — somatosensory evoked magnetic field; spectral edge frequency; staphylococcal enterotoxin F; structured encounter form; suction effusion fluid … Medical dictionary
SEF — • somatosensory evoked magnetic field; • spectral edge frequency; • staphylococcal enterotoxin F; • structured encounter form; • suction effusion fluid … Dictionary of medical acronyms & abbreviations
Jitter — For other meanings of this word, see Jitter (disambiguation). Jitter is the undesired deviation from true periodicity of an assumed periodic signal in electronics and telecommunications, often in relation to a reference clock source. Jitter may… … Wikipedia
Group velocity — [ Frequency dispersion in bichromatic groups of gravity waves on the surface of deep water. The red dot moves with the phase velocity, and the green dots propagate with the group velocity. In this deep water case, the phase velocity is twice the… … Wikipedia
spectroscopy — spectroscopist /spek tros keuh pist/, n. /spek tros keuh pee, spek treuh skoh pee/, n. the science that deals with the use of the spectroscope and with spectrum analysis. [1865 70; SPECTRO + SCOPY] * * * Branch of analysis devoted to identifying… … Universalium
