Constraints
(16)–(19) ensure that if a nurse is assigned to a surgery case, (s)he will stay for the entire
duration of the case unless there is a greater need for that nurse elsewhere. Such a need may
arise, for example, when limits on under coverage or room assignments cannot be maintained
without reassigning the nurse to another case prior to the termination of his or her current case.
Also, by minimizing the maximum number of cases that a nurse can work, N CT , we limit
the movement of nurses between cases.