A knowledge-based approach for railway scheduling

Proposed a new problem solving architecture for knowledge-based integration of simulation and scheduling and describes two knowledge-based systems for railway scheduling using it: DIAPLAN and ESTRAC-III. For railway scheduling, the most important point in the problem solving processes of experts is that they integrate simulation with scheduling in an intelligent manner. To emulate these processes on a computer, the architecture consists of four major components-partial simulation, basic commands, tactical knowledge and strategic knowledge. The partial simulation and basic commands are used for simulation of train movements in a subsystem, and tactical knowledge is used for local scheduling. Strategic knowledge is used to emulate the reasoning processes by performing partial simulation and local scheduling repeatedly in a specific order. Since these components are defined independently and layered hierarchically in the architecture, one can develop a knowledge-based system in a step-by-step manner by defining the four components in the order given above