id	keyword
fis-2503	crack
fis-2503	stress
fis-2503	tip
fis-2503	elasticity
fis-2503	strain
fis-2503	gradient
fis-2503	doi
fis-2503	fracture
fis-2503	sget
fis-2503	crack tip
fis-2503	model
fis-2503	solution