α	Fractal channel aspect ratio
p	Interspace of conical column structure
d	Tip size of conical column structure
h	Height of conical column structure
Dw	Departure diameter of droplet
ρw	Density of droplet
s+	Dimensionless spacing of groove
h+	Dimensionless height of groove
a+	Dimensionless amplitude of sinusoidal groove
λ+	Dimensionless wavelength of sinusoidal groove
dc	Depth of concave structure
s	Spacing of concave structure
CAD	Computer aided design
SEM	Scanning electron microscope
UV	Ultraviolet
PDMS	Polydimethylsiloxane
MTEOS	Methyltriethoxysilane
PMMA	Polymethyl methacrylate
SMP	Shape-memory polymer