Conference of the World-Academy-of-Science-Engineering-and-Technology, Prague, Çek Cumhuriyeti, 26 - 28 Ağustos 2005, cilt.7, ss.112-116, (Tam Metin Bildiri)
Imperfect knowledge cannot be avoided all the time. Imperfections may have several forms; uncertainties, imprecision and incompleteness.