Analysis on Port and Maritime Transport System Researches

Table 1

Process of the material collection.

		Search results
Step1	Search keywords	81,126
	port OR shipping OR maritime OR marine OR terminal OR ship OR liner OR seaport OR
	(water ) OR (ocean freight) OR container OR (waterway )
Step2	Exclusion keywords	78,482
	AND NOT
	highway OR intersection OR helmet OR pedestrian OR fish OR guardrail OR aviation
	OR airport OR airline OR fishery
Step3	Remove the irrelevant subject areas	12,279
Step4	Manual refinement of the search results	5,534