“…To mitigate this harmful effect, lifelong learning (or continual learning) has been explored, in which the network is updated to adapt to a new task (e.g., a new set of classes and a new instance) without forgetting the results of past learning. Major methods can be categorized into memory-replay-based [Rebuffi et al, 2017;Lopez-Paz and Ranzato, 2017], parameterfreezing-based [Mallya and Lazebnik, 2018;Mallya et al, 2018], and regularization-based [Kirkpatrick et al, 2017;Li and Hoiem, 2017;Zenke et al, 2017;Aljundi et al, 2018] approaches. Most existing methods have been designed to learn a highly expressive model for the new task while preserving all of the knowledge for the previous tasks.…”