Table 1.

Variables and symbols.

Symbol	Variable	Symbol	Variable
$v_e$	expected driving speed (km/h)	$a_{c2}$	acceleration of leading car (m/s2)
$d_e$	expected following distance (m)	$d$	relative distance between (m)
$v_1$	velocity of following car (km/h)	$\Delta v$	relative velocity (km/h)
$a_{c1}$	acceleration of following car (m/s2)	$\Delta a_c$	relative acceleration (m)
$v_2$	velocity of leading car (km/h)