id	keyword
app01-9501	tram
app01-9501	accident
app01-9501	figure
app01-9501	car
app01-9501	collision
app01-9501	simulation
app01-9501	type
app01-9501	vehicles
app01-9501	model
app01-9501	consequences
app01-9501	research
app01-9501	impact
app01-9501	cars
app01-9501	transport