Title: Quantum torus algebras and B(C) type Toda systems,
Abstract: In this paper, we construct a new even constrained B(C) type Toda hierarchy
and derive its B(C) type Block type additional symmetry. Also we generalize the
B(C) type Toda hierarchy to the $N$-component B(C) type Toda hierarchy which is
proved to have symmetries of a coupled $\bigotimes^NQT_+ $ algebra ( $N$-folds
direct product of the positive half of the quantum torus algebra $QT$).