<正>In this paper, we examine further annuity-due risk model presented by Cai (Probability in the Engineering and Informational Sciences, 16(2002), 309-324). We
<正>Due to its complexities in both mathematical formulations and applica- tions,universal co-kriging(UCK)has not been sufficiently discussed in literature.An e
<正> Let R be a ring.A right R-module M with S=End(MR)is called aquasi AP-injective module,if,for any s ∈ S,there exists a left ideal X_s of S such thatl_s(ker