id	keyword
fbem-11831	development
fbem-11831	urban
fbem-11831	agglomeration
fbem-11831	transportation
fbem-11831	guanzhong
fbem-11831	economic
fbem-11831	economy
fbem-11831	cities
fbem-11831	network
fbem-11831	level
fbem-11831	system
fbem-11831	construction
fbem-11831	xi'an