We give a bosonization of the quantum affine superalgebra $U_q(widehat{sl}(N|1))$ for an arbitrary level $k in {bf C}$. The bosonization of level $k in {bf C}$ is completely different from those of level $k=1$. From this bosonization, we induce the W
akimoto realization whose character coincides with those of the Verma module. We give the screening that commute with $U_q(widehat{sl}(N|1))$. Using this screening, we propose the vertex operator that is the intertwiner among the Wakimoto realization and typical realization. We study non-vanishing property of the correlation function defined by a trace of the vertex operators.
We explicitly construct two classes of infinitly many commutative operators in terms of the deformed Virasoro algebra. We call one of them local integrals and the other nonlocal one, since they can be regarded as elliptic deformations of the local an
d nonlocal integrals of motion obtained by V.Bazhanov, S.Lukyanov and Al.Zamolodchikov.
We explicitly construct two classes of infinitly many commutative operators in terms of the deformed W-algebra $W_{qt}(sl_N^)$, and give proofs of the commutation relations of these operators. We call one of them local integrals of motion and the oth
er nonlocal one, since they can be regarded as elliptic deformation of local and nonlocal integrals of motion for the $W_N$ algebra.
