Depart is related to Arrive. Arrival is derived from Arrive. 
Investigator is a type of Expert. Technician is a type of Expert. Technician is a type of Professional. Professional is related to Detective. 
Depart <--RelatedTo--> Arrive <--DerivedFrom-- Arrival 
Investigator --IsA--> Expert <--IsA-- Technician --IsA--> Professional <--RelatedTo--> Detective 