NationMaster - Encyclopedia: Degree day

A degree day is a measure of heating or cooling. Degree days are used to plan the planting of crops and management of pests. Degree days may also be used to plan for heating and cooling costs of climate controlled buildings. A red-hot iron rod cooling after being worked by a blacksmith. ... Crop has several meanings: A crop is a plant domesticated for use in agriculture, considered as a group (eg. ... Look up Pest in Wiktionary, the free dictionary Pest may refer to: A pest, an animal (usually an insect), or sometimes a plant (weed) with characteristics that are injurious or harmful to humans. ... HVAC may also stand for High-voltage alternating current HVAC is an initialism that stands for heating, ventilation and air_conditioning. This is sometimes referred to as climate control. ...

A degree day is computed as the integral of a function of time that generally varies with temperature. The function is truncated to upper and lower limits that vary by organism, or to limits that are appropriate for climate control. The function is typically estimated to be a sine wave with amplitude equal to the day's temperature variation. In calculus, the integral of a function is a generalization of area, mass, volume, sum, and total. ... Look up Function on Wiktionary, the free dictionary In general (not in the mathematical but in the engineering sense), a function is a goal-oriented property of an entity (according to the Adam Maria Gadomskis TOGA meta-theory, 1993). ... A watch Attempting to understand Time has long been a prime occupation for philosophers, scientists and artists. ... Temperature is the physical property of a system which underlies the common notions of hot and cold; the material with the higher temperature is said to be hotter. ... In trigonometry, an ideal sine wave is a waveform whose graph is identical to the generalized sine function y = Asin[ω(x − α)] + C, where A is the amplitude, ω is the angular frequency (2π/P where P is the wavelength), α is the phase shift, and C is the... Amplitude is a nonnegative scalar measure of a waves magnitude of oscillation, that is, magnitude of the maximum disturbance in the medium during one wave cycle. ...