Sandwich theorySandwich theory describes the behaviour of a beam, plate, or shell which consists of three layers—two facesheets and one core. The most commonly used sandwich theory is linear and is an extension of first-order beam theory. The linear sandwich theory is of importance for the design and analysis of sandwich panels, which are of use in building construction, vehicle construction, airplane construction and refrigeration engineering. Some advantages of sandwich construction are: Sandwich cross sections are composite.
Effects unitAn effects unit or effects pedal is an electronic device that alters the sound of a musical instrument or other audio source through audio signal processing. Common sound effects include distortion/overdrive, often used with electric guitar in electric blues and rock music; dynamic effects such as volume pedals and compressors, which affect loudness; filters such as wah-wah pedals and graphic equalizers, which modify frequency ranges; modulation effects, such as chorus, flangers and phasers; pitch effects such as pitch shifters; and time effects, such as reverb and delay, which create echoing sounds and emulate the sound of different spaces.
Tower BridgeTower Bridge is a Grade I listed combined bascule and suspension bridge in London, built between 1886 and 1894, designed by Horace Jones and engineered by John Wolfe Barry with the help of Henry Marc Brunel. It crosses the River Thames close to the Tower of London and is one of five London bridges owned and maintained by the Bridge House Estates, a charitable trust founded in 1282. The bridge was constructed to give better access to the East End of London, which had expanded its commercial potential in the 19th century.
