you are likely to find Town in/at/on County. you are likely to find Sign in/at/on Town. Sign is a synonym of Signal. Alarm is a type of Signal. 
Center is related to Factory. Factory is related to Business. you are likely to find Business in/at/on Building. Building is related to Shade. 
County <--AtLocation-- Town <--AtLocation-- Sign <--Synonym--> Signal <--IsA-- Alarm 
Center <--RelatedTo--> Factory <--RelatedTo--> Business --AtLocation--> Building <--RelatedTo--> Shade 