Optimization of Gantry Crane Scheduling in Container Sea-Rail Intermodal Transport Yard

Table 1

The definitions of symbols.

Symbol	Definition
	The set of task groups
	The number of tasks that are included in task group
	The set of gantry cranes that can be scheduled in the yard
	The set of blocks
	The number of tasks completed by gantry crane in block during the planned period
	Task overflow of task group during the planned period
	Task overflow in the block during the previous period
	The maximum working capacity of each gantry crane during the planned period
	The distance from block to block
	The time when gantry crane moves from block to block
	The time when gantry crane tires are rotated through 90 degrees once
	The moving speed of gantry cranes
	Average operating efficiency of gantry cranes
	The set of railway loading and unloading lines
	The moment when the gantry crane reaches loading and unloading line
	The moment when gantry crane departs loading and unloading line
	The moment when the pth container train reaches loading and unloading line
	The moment when the pth container train departs loading and unloading line
	A binary parameter satisfying , if block has task group ; and , otherwise
	A binary parameter satisfying , if gantry crane is placed in block in the initial state; and , otherwise
	A binary variable satisfying , if gantry crane handles task group during the planned period; and , otherwise
	A binary variable satisfying , if gantry crane moves from block to block ; and , otherwise