Flexible Optimization of International Shipping Routes considering Carbon Emission Cost

Table 1

Variable declaration.

Symbol	Symbol meaning
	Total profit on routes excluding operating and capital costs (USD)
	Number of ports in routes
	Fuel price ($/ ton)
	Port and port
	The distance from port to port (nautical mile)
	The speed at which ships sail on the course (knot)
	Ship functional coefficient
	Port surcharge such as terminal charge
	Standard container handling charges (USD/TEU)
	Penalty coefficient for port skip, between 0 and 1
	Container volume from port to port
	Actual demand for container transport between port to port
	Standard container unit freight at port to port (USD/TEU)
	Carbon emission cost (USD/TEU)
	Pilotage time of container ships in ports and other time consumption other than loading and unloading time (h)
	Container handling speed (TEU/h)
	The cost of a ship at anchor (USD/TEU)
	The maximum time that the shipping company specifies at which the ship will travel on that route (hour)
	Maximum liner load
	Auxiliary coefficient