A high-fidelity, machine-learning enhanced queueing network simulationmodel for hospital ultrasound operations - Pan, Yihan; Xu, Zhenghang; Guang, Jin; Sun, Jingjing; Wang, Chengwenjian; Zhang, Xuanming; Chen, Xinyun; Dai, Jiangang; Ding, Yichuan Daniel; Shi, Pengyi; Pan, Hongxin; Yang, Kai; et al. (Proceedings of the Winter Simulation Conference 2021, 2021)