@article{betts_campbell_digirolamo_2021, title={EXAMINATION OF SOLVING OPTIMAL CONTROL PROBLEMS WITH DELAYS USING GPOPS-II}, volume={11}, ISSN={["2155-3297"]}, DOI={10.3934/naco.2020026}, abstractNote={There are a limited number of user-friendly, publicly available optimal control software packages that are designed to accommodate problems with delays. GPOPS-Ⅱ is a well developed MATLAB based optimal control code that was not originally designed to accommodate problems with delays. The use of GPOPS-Ⅱ on optimal control problems with delays is examined for the first time. The use of various formulations of delayed optimal control problems is also discussed. It is seen that GPOPS-Ⅱ finds a suboptimal solution when used as a direct transcription delayed optimal control problem solver but that it is often able to produce a good solution of the optimal control problem when used as a delayed boundary value solver of the necessary conditions.}, number={2}, journal={NUMERICAL ALGEBRA CONTROL AND OPTIMIZATION}, author={Betts, John T. and Campbell, Stephen and Digirolamo, Claire}, year={2021}, month={Jun}, pages={283–305} }
 @article{betts_campbell_digirolamo_2020, title={INITIAL GUESS SENSITIVITY IN COMPUTATIONAL OPTIMAL CONTROL PROBLEMS}, volume={10}, ISSN={["2155-3297"]}, DOI={10.3934/naco.2019031}, abstractNote={An optimal control problem is presented that exhibited unexpected initial guess dependence when being solved with direct transcription methods. This note presents that example and the cautionary tale it provides.}, number={1}, journal={NUMERICAL ALGEBRA CONTROL AND OPTIMIZATION}, author={Betts, John T. and Campbell, Stephen L. and Digirolamo, Claire}, year={2020}, month={Mar}, pages={39–43} }