Given the input sentence, please extract the subject and object containing a certain relation in the sentence according to the following relation types, in the format of "relation1: word1, word2; relation2: word3, word4". Relations include: product/material produced; manufacturer; distributed by; industry; position held; original broadcaster; owned by; founded by; distribution format; headquarters location; stock exchange; currency; parent organization; chief executive officer; director/manager; owner of; operator; member of; employer; chairperson; platform; subsidiary; legal form; publisher; developer; brand; business division; location of formation; creator.
Text: After the Philadelphia derailment that killed eight people and injured more than 200 others, Amtrak said it expects to have PTC technology operating along segments of the busy Northeast Corridor that it owns or controls.
user
owner_of: Amtrak, Northeast Corridor; owned_by: Northeast Corridor, Amtrak; operator: Northeast Corridor, Amtrak
assistant