释义 |
r-value \ˈ ̷ ̷ ¦ ̷ ̷ (ˌ) ̷ ̷ \ noun Usage: usually capitalized R Etymology: probably from thermal resistance : a measure of resistance to the flow of heat through a given thickness of a material (as insulation) with higher numbers indicating better insulating properties — compare u-value herein |