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Rapid eye movement sleep. Rapid eye movement sleep ( REM sleep or REMS) is a unique phase of sleep in mammals (including humans) and birds, characterized by random rapid movement of the eyes, accompanied by low muscle tone throughout the body, and the propensity of the sleeper to dream vividly. The REM phase is also known as paradoxical sleep ...
Raymond Brownell (17 May 1894 – 12 April 1974) was a senior officer in the Royal Australian Air Force (RAAF) and a World War I flying ace. He enlisted in the Australian Imperial Force at the outbreak of World War I and served in the Gallipoli campaign before transferring to the Western Front. Awarded the Military Medal for his actions during ...
Monte Carlo method. The approximation of a normal distribution with a Monte Carlo method. Monte Carlo methods, or Monte Carlo experiments, are a broad class of computational algorithms that rely on repeated random sampling to obtain numerical results. The underlying concept is to use randomness to solve problems that might be deterministic in ...
Breeder reactor. A breeder reactor is a nuclear reactor that generates more fissile material than it consumes. [1] These reactors can be fueled with more-commonly available isotopes of uranium and thorium, such as uranium-238 and thorium-232, as opposed to the rare uranium-235 which is used in conventional reactors.
Wireless network technologies. In telecommunications, 5G is the fifth-generation technology standard for cellular networks, which cellular phone companies began deploying worldwide in 2019, and is the successor to 4G technology that provides connectivity to most current mobile phones. Like its predecessors, 5G networks are cellular networks, in ...
Numerical value, notation, and units The speed of light in vacuum is usually denoted by a lowercase c, for "constant" or the Latin celeritas (meaning 'swiftness, celerity'). In 1856, Wilhelm Eduard Weber and Rudolf Kohlrausch had used c for a different constant that was later shown to equal √ 2 times the speed of light in vacuum. . Historically, the symbol V was used as an alternative symbol ...
The speed of sound is the distance travelled per unit of time by a sound wave as it propagates through an elastic medium. At 20 °C (68 °F), the speed of sound in air is about 343 m/s (1,125 ft/s; 1,235 km/h; 767 mph; 667 kn ), or 1 km in 2.91 s or one mile in 4.69 s. It depends strongly on temperature as well as the medium through which a ...
