Abstract—Time/cost trade-offs problems in the project
management is the important role. The project scheduling with
the traditional approach does not consider the difference
execution time on the unit period for all activities of project. In
this paper, firstly, it presents an introduction of the problem
description of time-switch constraints. Then, the project
scheduling with time-switch constraints under the resource
constraints is proposed. Time/cost trade-offs problems, it takes
the Max-NPV as the objective function. Moreover, we build the
mathematic model about the TCTPTSC from the view of the
contractor. Finally, it validates by adopting a numerical example.
The results show that time-switch constraints can change the
arrangements for project scheduling more closely to realistic
situation, with the view real returns by the NPV(Net present
value), so the contractor can carry out accurate decision-making
and project control.