Navigation constellation availability research based on multi-echelon technique for recoverable item control theoryLingfeng ZHAO, Chaowei HUANG, Ruoyu LIN, Shasha HUANG, Xiaofeng XUE and Yunwen FENGJNWPU, 43 2 (2025) 222-232DOI: https://doi.org/10.1051/jnwpu/20254320222