MLC shape matrix decomposition without tongue-and-groove underdosage
نویسندگان
چکیده
Leaf sequencing is an important step in IMRT treatment planning. A given fluence matrix has to be decomposed into a sum of binary matrices corresponding to fields deliverable with a multileaf collimator. We consider the problem to find such a decomposition with minimal delivery time. It is shown how the network flow formulation from [4] can be modified to take tongue-and-groove underdosage effects into account. In addition, we present a lower bound and a heuristic approach to the problem. Finally, we compare the heuristic results on randomly generated test instances with the exact solutions obtained with the MIP solver SCIP [1].
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تاریخ انتشار 2008