SAC Flow: Sample-Efficient Reinforcement Learning of Flow-Based Policies via Velocity-Reparameterized Sequential Modeling - Zhang, Yixian; Yu, Shu-ang; Zhang, Tonghe; Guang, Mo; Hui, Haojia; Long, Kaiwen; Wang, Yu; Yu, Chao; Ding, Wenbo (International Conference on Learning Representations, 2026)