＜正＞ Suppose X = （Xr, Fr, t ∈ R+） be an optional reward process with （ Fr） satisfying usual conditions. In this paper, we correct the proof of existence about Snell envelope in [4] and the proof of an important lemma （Lemma 4. 6） in [5], and give a proof of existence about Snell envelope under certain conditions, i. e. EZx- ＜ ∞ and Z is upper-semi-continuous on the right （USCR） or there is a stopping rule （SR）τ ≤σ such that EZx-∞ for any stopping rule σ . At the same time, we prove a four-repeated limit theorem when Z is continuous on the right. The character and the uniqueness of the optimal stopping time （OST） or optimal stopping rule （OSR） are discussed.
展开▼
机译：Screening of Dhase/Dcase-producing Strain and its Optimal Fermentation Process for the Production of D-HydroxyphenylglycineAU Luo, Maochun (150391768@qq.com) Wu, Yaohui Wang, Yongle Lin, Biaosheng
