Pipe is related to Tube. Barrel is a type of Tube. Barrel is related to Bullet. 
Museum can be used for Art. Art is related to Design. Design is related to Publicity. 
Pipe <--RelatedTo--> Tube <--IsA-- Barrel <--RelatedTo--> Bullet 
Museum --UsedFor--> Art <--RelatedTo--> Design <--RelatedTo--> Publicity 