ABSTRACT
UAM — Acronym for urban airshed model. UAO — See upper airway obstruction. UAQI — Acronym for uniform air quality index. UARS — See Upper Atmosphere Research Satellite. U-blade — A bulldozer blade with an extension on each
side to increase moving capacity. UC — Notation for uniformity coefficient. UCC — Acronym for ultra-clean coal. UCL — Acronym for upper control limit. UEL — See upper explosive limit. UF — See uncertainty factor. UFFI — Acronym for urea-formaldehyde foam insulation. UFL — See upper flammable limit. UHF — See ultra-high-frequency. UHV — See ultra-high-voltage. UIC — Acronym for underground injection control. ulcer — Destruction of skin or mucous membrane with
or without infection or pain. ulceration — Formation of an open sore or ulcer. ULEV — Acronym for ultra-low-emission vehicle. ultimate analysis — Chemical analysis of a solid, liquid,
or gaseous fuel to determine the amounts of carbon, hydrogen, sulfur, nitrogen, oxygen, and ash it contains.
