  In most existing works on non-orthogonal multiple access (NOMA), the decoding
order of successive interference cancellation (SIC) is prefixed and based on
either the users' channel conditions or their quality of service (QoS)
requirements. A recent work on NOMA assisted semi-grant-free transmission
showed that the use of a more sophisticated hybrid SIC scheme can yield
significant performance improvements. This letter illustrates how the concept
of hybrid SIC can be generalized and applied to different NOMA applications. We
first use NOMA assisted mobile edge computing (MEC) as an example to illustrate
the benefits of hybrid SIC, where new results for delay and energy minimization
are presented. Then, future directions for generalizing hybrid SIC with
adaptive decoding order selection as well as its promising applications are
discussed.
