IPOPT

Superiorization as a novel strategy for linearly constrained inverse radiotherapy treatment planning

  • Florian Barkmann
  • Yair Censor
  • Niklas Wahl
    • Categories Biomedical Applications, Constrained Nonlinear Optimization, Convex Optimization Tags , , , , , ,

    Objective: We apply the superiorization methodology to the intensity-modulated radiation therapy (IMRT) treatment planning problem. In superiorization, linear voxel dose inequality constraints are the fundamental modeling tool within which a feasibility-seeking projection algorithm will seek a feasible point. This algorithm is then perturbed with gradient descent steps to reduce a nonlinear objective function. Approach: Within … Read more

    Using an Analytical Computational-Geometry Library to Model Nonoverlap and Boundary-Distance Constraints and their Application to Packing Poly-Bézier Shapes

  • Paul Morton
    • Categories Applications - Science and Engineering, Bound-constrained Optimization, Optimization Software and Modeling Systems Tags , , , , , , , , , , ,

    In this paper we will show how to model nonoverlap as well as uniform and nonuniform boundary-distance constraints between poly-Bézier shapes using an analytical computational-geometry library. We then use this capability to develop, implement and analyze analytical-optimization solutions to minimum-area rectangular-boundary packing-problems as well as minimum-area one- and two-dimensional puzzle-piece packing-problems. In the process, we … Read more