An optimal control problem for a semilinear elliptic partial differential equation is discussed subject to pointwise control constraints on the control and the state. The main novelty of the paper is the presence of the L1-norm of the control as part of the objective functional that eventually leads to sparsity of the optimal control functions. Second-order sufficient optimality conditions are ...

We discuss error estimates for the numerical analysis of Neumann boundary control problems. We present some known results about piecewise constant approximations of the control and introduce some new results about continuous piecewise linear approximations. We obtain the rates of convergence in i ^ ( r ) . Error estimates in the uniform norm are also obtained. We also discuss the semidiscretiza...

In this article, we show the existence and uniqueness of smooth solutions for boundary-value problems of semilinear elliptic systems.