ANN	Artificial neural network
AEROS	Atmospheric environmental regional observation system
CART	Classification and regression tree
CO	Carbon monoxide
CO${}_2$	Carbon dioxide
CV	Cross-validation
DRNN	Deep recurrent neural networks
DTT	Dynamic pre-training
EELM	Ensemble extreme learning machine
FC	Fight controller
FPV	First person view
FRP	Fiber reinforced plastics
GBR	Gradient boosting regression
GBM	Gradient boosting machine
GPS	Global positioning system
GPIO	General-purpose input–output
GT	Ground truth
GUI	Graphical user interface
I2C	Inter-integrated circuit
IoT	Internet of things
IMU	Inertial measurement unit
INP	Ice nucleation particles
k-NN	k-nearest neighbor
LCS	Long-range wireless communication system
LiDAR	Light detection and ranging
LoRa	Long range
LPWA	Low power wide area
LPWAN	Low-power wide-area network
LSTM	Long short-term memory
MAE	Mean absolute error
MSS	Multi-sensor system
NBIoT	Narrow band-Internet of things
NDIR	Non-dispersive infrared
NO	Nitric oxide
NO${}_2$	Nitrogen dioxide
OS	Operating system
PM	Particulate matter
PP	Polypropylene
PWM	Pulse width modulation
RF	Random forest
RM	Receiver module
RNN	Recurrent neural network
RTC	Real-time clock
RVS	Real-time visualization system
SBC	Single board computer
SfM	Structure from motion
SGD	Stochastic gradient descent
SVR	support vector regression
SVM	Support vector machine
TEOM	Tapered element oscillating microbalance
TM	Transmitter module
3D	Three-dimensional
UAV	Unmanned aerial vehicles
UFP	Ultrafine particles
USB	Universal serial bus
UV	Ultraviolet