Classically and Quantum Integrable Systems with Boundary
  We study two-dimensional classically integrable field theory with independent boundary condition on each end, and obtain three possible generating functions for integrals of motion when this model is an ultralocal one. Classically integrable boundary condition can be found in solving boundary $K_{\pm}$ equations. In quantum case, we also find that unitarity condition of quantum $R$- matrix is sufficient to construct commutative quantities with boundary, and its reflection equations are obtained. 
Yi-Xin Chen, Xu-Dong Luo and Ke Wu