  We investigate how to protect quantum correlations for two qubits each
locally interacting with its own non-Markovian environment by making use of
bang-bang pulses. It is shown that the quantum discord dynamics presents the
phenomenon of sudden change for some certain initial states. We also find that
the amount of quantum correlation between two qubits can be improved by
applying a train of pulses and protected more effectively with shorter interval
pulses or longer reservoir correlation time.
