id	keyword
american_scientific_journal-4941	pavement
american_scientific_journal-4941	axle
american_scientific_journal-4941	traffic
american_scientific_journal-4941	load
american_scientific_journal-4941	road
american_scientific_journal-4941	design
american_scientific_journal-4941	life
american_scientific_journal-4941	vehicle
american_scientific_journal-4941	standard
american_scientific_journal-4941	engineering
american_scientific_journal-4941	condition
american_scientific_journal-4941	direction