| Article ID: | iaor2000350 |
| Country: | United States |
| Volume: | 101 |
| Issue: | 2 |
| Start Page Number: | 375 |
| End Page Number: | 402 |
| Publication Date: | May 1999 |
| Journal: | Journal of Optimization Theory and Applications |
| Authors: | Raymond J.P., Zidani H. |
We consider time-optimal control problems for semilinear parabolic equations with pointwise state constraints and unbounded controls. A Pontryagin's principle is obtained in nonqualified form without any qualification condition. The terminal time, which is a control variable, satisfies an optimality condition, which seems to be new in the context of control problems for partial differential equations.