Automated Case-Based Scheduling for Power Plant Boiler Erection: Use of Annotated Schedules

Contractors who repeatedly build the same kind of facilities accumulate experience in scheduling the needed construction work. When parts of a facility’s design are copied from one project to the next, the previously developed schedules could be refused to schedule future work. The aim of the presented research is to articulate project characteristics and describe associated schedules, to accomplish such reuse. This paper describes the need for annoting a schedule with constraints pertaining to the facility design and construction resources, in addition to providing traditional scheduling data. It also presents a case-based reasoning system, called CasePlan. CasePlan automates the generation of construction schedules for power plant boiler erection by reusing annotated schedules. Power plant boilers have a more or less standardized design, notwithstanding design variations to optimize combustion of the fuel used in each plant. A boiler product model serves as the basics for comparing designs and assessing their similarities, in order to select the associated construction schedules for reuse. This automated scheduler tries to mimic the scheduling activity of human planners which could learn from experience as people do through the use of cases. Case-based reasoning avoids the need to encode fundamental theories of physics and default logic that are otherwise required by automated schedulers that plan from scratch.