Degree (temperature) temperature: (Measurement of temperature) "Degrees Kelvin" (K) is a former name for the SI unit of temperature on the thermodynamic (absolute) temperature scale. Since 1967 it has been known simply as the kelvin, with symbol K (without a degree symbol). Degree absolute (°A) is obsolete terminology, often referring specifically to the kelvin but sometimes the degree Rankine as well. Degree (temperature) The term degree is used in several scales of temperature. The symbol ° is usually used, followed by the initial letter of the unit, for example “°C” for degree(s) Celsius. A degree can be defined as a set change
Hounsfield scale Hounsfield scale The Hounsfield scale , named after Sir Godfrey Hounsfield, is a quantitative scale for describing radiodensity. It is frequently used in CT scans, where its value is also termed CT number. The Hounsfield unit (HU) scale is a linear transformation of the original linear attenuation coefficient measurement into one in which the radiodensity of distilled water at standard pressure and temperature (STP) is defined as zero Hounsfield units (HU), while the radiodensity of air at STP is defined as -1000 HU. In a voxel with average linear attenuation coefficient formula_1, the corresponding HU value is therefore given by: