Symbol
${\mathrm{L}}_{\mathrm{WECPN}}$	Weighted equivalent continuous perceived noise level
R	The distance between the measurement point and the aircraft track
${\mathrm{L}}_{\mathrm{EPN}}$	Effective perceived noise level
${\bar{\mathrm{L}}}_{\mathrm{EPN} }$	Energy average of effective perceived noise level
${\mathrm{N}}_1$, ${\mathrm{N}}_2$, ${\mathrm{N}}_3$	The number of aircrafts during day (7:00∼19:00), evening (19:00∼22:00) and night (22:00∼7:00)
${\mathrm{R} }_{\mathrm{w}}$	Weighted sound reduction index
${\mathrm{L}}_{\mathrm{WECPN}\left(\mathrm{l}\right)}$	Noise limit of weighted equivalent continuous perceived noise level
${\mathrm{L}}_{\mathrm{A}(\mathrm{l} )}$	Noise limit of A-weighted maximum sound pressure level
Abbreviations
BIA	Guangzhou Baiyun International Airport
NPD	Noise–Power–Distance data
ANP	Aircraft noise and performance
EEC	Eurocontrol Experimental Centre