Abstract: This paper considers a class of networked control systems subject to periodic pulsewidth-modulated (PWS) denial-of-service (DoS) attacks, the information of which is partially known. The DoS attack is considered under the assumption that it could be monitored and the period of the jammer and a uniform lower bound on the jammer's sleeping time are known. To reduce the release frequency of packets in NCSs, a novel memory-event-triggered novel scheme based on relative errors is first proposed. Compared with the traditional event-triggered scheme, the proposed scheme allows the event generator to compare the newest sampled packet with much more recent released packets by using buffers. In this way, the control performance can be improved. Next, by combining the DoS attacks with the memory-event-triggered scheme, a switched networked control system was constructed. The exponential stability criteria have been derived using the piecewise Lyapunov method.