Qi, Q.; Jiang, Y., and Wang, D., 2020. Evaluation of port unified efficiency based on RAM-DEA model for port sustainable development. In: Guido Aldana, P.A. and Kantamaneni, K. (eds.), Advances in Water Resources, Coastal Management, and Marine Science Technology. Journal of Coastal Research, Special Issue No. 104, pp. 724–729. Coconut Creek (Florida), ISSN 0749-0208.

Unified efficiency is essential in evaluating the balance between operational performance and environment of port, since Green Port is becoming the core concept of port development. This research utilizes a Range Adjusted Measure - Data Envelopment Analysis (RAM-DEA) model with natural and managerial disposability to evaluate the port unified efficiency from two aspects of both operational performance and environment, and determine the types of returns to scale (RTS) and damages to scale (DTS). Statistical data from 10 ports along the Yangtze River in Jiangsu Province are empirically examined using the RAM-DEA model. The results indicate that the RAM-DEA model is a feasible approach for port unified efficiency evaluation. Moreover, combined with the exactly types of RTS and DTS, the RAM-DEA model can support port enterprise in choosing the suitable development direction for the sustainable development of port.