The main characteristics of straddle carrier direct system and straddle carrier relay system are stated and factors affecting the economics of this two handling systems are also studied. A cost function model is proposed to make the comparison. It includes land cost, equipment cost, transportation cost between quayside and storage yard, annual throughput, handling efficiency, labor cost and their constituent factors. A "handling cost comparison indicator" (RD) is also submitted to determine the preferred system. For RD > 1 scenario, straddle carrier direct system is preferred, and on the contrary, straddle carrier relay system is preferred, if RD < 1.
Huang, Wen-Chih and Chu, Chin-Yuan
"Cost Comparison of Straddle Carrier Direct and Relay Systems in Container Terminals,"
Journal of Marine Science and Technology: Vol. 11
, Article 3.
Available at: https://jmstt.ntou.edu.tw/journal/vol11/iss4/3