ology ▁or ▁politics . ▁Each ▁domain ▁ont ology ▁typically ▁models ▁domain - specific ▁definitions ▁of ▁terms . ▁For ▁example , ▁the ▁word ▁card ▁has ▁many ▁different ▁mean ings . ▁An ▁ont ology ▁about ▁the ▁domain ▁of ▁pok er ▁would ▁model ▁the ▁" play ing ▁card " ▁meaning ▁of ▁the ▁word , ▁while ▁an ▁ont ology ▁about ▁the ▁domain ▁of ▁computer ▁hardware ▁would ▁model ▁the ▁" p unch ed ▁card " ▁and ▁" video ▁card " ▁mean ings . ▁ ▁Since ▁domain ▁ont ologies ▁are ▁written ▁by ▁different ▁people , ▁they ▁represent ▁concepts ▁in ▁very ▁specific ▁and ▁unique ▁ways , ▁and ▁are ▁often ▁in compatible ▁within ▁the ▁same ▁project . ▁As ▁systems ▁that ▁rely ▁on ▁domain ▁ont ologies ▁expand , ▁they ▁often ▁need ▁to ▁merge ▁domain ▁ont ologies ▁by ▁hand - t uning ▁each ▁entity ▁or ▁using ▁a ▁combination ▁of ▁software ▁mer ging ▁and ▁hand - t uning . ▁This ▁presents ▁a ▁challenge ▁to ▁the ▁ont ology ▁designer . ▁D ifferent ▁ont ologies ▁in ▁the ▁same ▁domain ▁arise ▁due ▁to ▁different ▁languages , ▁different ▁intended ▁usage ▁of ▁the ▁ont ologies , ▁and ▁different ▁per ception s ▁of ▁the ▁domain ▁( based ▁on ▁cultural ▁background , ▁education , ▁ide ology , ▁etc .). ▁ ▁At ▁present , ▁mer ging ▁ont ologies ▁that ▁are ▁not ▁developed ▁from ▁a ▁common ▁upper ▁ont ology ▁is ▁a ▁largely ▁manual ▁process ▁and ▁therefore ▁time - consum ing ▁and ▁expensive . ▁Domain ▁ont ologies ▁that ▁use ▁the ▁same ▁upper ▁ont ology ▁to ▁provide ▁a ▁set ▁of ▁basic ▁elements ▁with ▁which ▁to