In VHDL, "Transmission delay" and "inertia delay"

The transmission delay is the easiest to understand the delay between the input change and the output change. The corresponding syntax is transport
For example B <= transport a after 20ns

Inertia delay takes into account the capacitive effect, that is, if the input is a (relatively) narrow pulse, it will be ignored and will not react to the output.
For example z<= X after 20ns
If x has a pulse less than 20ns (i.e. continuous rollover within 20ns) Z will remain constant or it will reflect the pulse (or a single flip) that is not less than 20ns after 20ns.

In VHDL, "Transmission delay" and "inertia delay"