SN	Symbol	Description of the Symbols
1	$l_{CE}$	Cross Entropy-loss
2	m	Model used for segmentation in the total number of models M
3	n	Image scan number in total number N
4	${\overline{A}}_{ai}\left(m\right)$	Mean estimated lung area for all images using AI model ‘m’
5	$A_{ai}\left(m,n\right)$	Estimated Lung Area using AI model ‘m’ and image ‘n’
6	$A_{gt}\left(n\right)$	GT lung area for image ‘n’
7	${\overline{A}}_{gt}$	Mean ground truth area for all images N in the database
8	${\overline{LA}}_{ai}\left(m\right)$	Mean estimated lung long axis for all images using AI model ‘m’
9	$L{A}_{ai}\left(m,n\right)$	Estimated lung long axis using AI model ‘m’ and image ‘n’
10	$L{A}_{gt}\left(n\right)$	GT lung long axis for image ‘n’
11	${\overline{LA}}_{gt}$	Mean ground truth long axis for all images N in the database
12	$Fo{M}_A\left(m\right)$	Figure-of-Merit for segmentation model ‘m’
14	$Fo{M}_{LA}\left(m\right)$	Figure-of-Merit for long axis for model ‘m’
15	JI	Jaccard Index for a specific segmentation model
16	DSC	Dice Similarity Coefficient for a specific segmentation model
17	TP, TN	True Positive and True Negative
18	FP, FN	False Positive and False Negative
19	x i	GT label
20	pi	SoftMax classifier probability
21	Yp	Ground truth image
22	$\widehat{Y_p}$	Estimated image
23	P	Total no of pixels in an image in x, y-direction
24	K5	Cross-validation protocol with 80% training and 20% testing (5 folds)
Deep Learning Segmentation Architectures
25	PSP Net	SDL model for lung segmentation with pyramidal feature extraction
26	VGG-SegNet	HDL model designed by fusion of VGG-19 and SegNet architecture
27	ResNet-SegNet	HDL model designed by fusion of ResNet-50 and SegNet architecture