We propose an estimator for the mean of random variables in separable real Banach spaces using empirical characteristic function. Assuming that covariance operator variable is bounded a precise sense, we show proposed achieves optimal sub-Gaussian rate, except faster decaying mean-dependent term. Under mild condition, iterative refinement procedure can essentially eliminate term and provide shi...

The work aims to study the change rule of surface properties aluminum (Al) alloy after shot peening (SP), and obtain corresponding relationship between material characteristics SP parameters. Firstly, Finite Element Model (FEM) multi-projectile impact Al specimen was established by ANSYS/LS-DYNA (Version: Ansys15.0). Box-Benhnken design method (BBD) used 3-level 3-factor experiment with pressur...