Semi-definite programming based approaches for real-time tractor localization in port container terminals

In order to effectively manage and deploy internal tractors in a port container marine terminal, real-time information concerning the location of the tractors is required so that timely scheduling and planning of tractors control and dispatching can be derived. This paper propose a wireless sensor network-based Truck Flow Management System (TFMS) to help tracking the real-time location of internal tractors in a container terminal so as to streamline the management of the terminal operation. Focusing on the real-time localization, the semi-definite programming (SDP) based approaches are employed by introducing the terminal context information, including prior known road constraints and available time-serial data recorded in the network, into the traditional SDP formulation. Experimental results are presented to show that the proposed formulation and treatments to the problem can greatly decrease the estimated errors compared to the traditional formulation.