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The paper investigates the features of emissions and fuel consumption (EFC) in a car-following (CF) platoon based on two experimental datasets. Four classical EFC models are employed and a universal concave growth pattern of the EFC along a platoon has been demonstrated. A general framework of coupling EFC and CF models is tested by calibrating and simulating three classical CF models. This work first demonstrates that, at vehicle-pair level, all models perform well on EFC prediction. The intelligent driver model outperforms the other CF models on calibration accuracy, but this is not true on EFC prediction. Second, at platoon level, the predicted EFC is nearly constant along the platoon which qualitatively differs from the experimental observation. The investigation highlights that accurate estimations at vehicle level may be insufficient for analysis at platoon level due to the significant role of oscillation growth and evolution in EFC estimation.

Over the years many shipping lines have established terminal operation companies, with some set up as independent firms. However, port authorities and local governments have not always welcomed external investment and control with open arms. The economic implications and each stakeholder’s best strategies remain unclear. This study develops an analytical model in order to study the effects of vertical integration, with a focus on shipping lines’ investment in ports’ capacity. Modelling results suggest that vertical integration between terminal operator and a shipping line leads to higher port capacity, port charge, market output and consumer surplus. It also reduces delay costs. All these results suggest that vertical integration can be an important source of synergy for the maritime industry. Although vertical integration increases the participating carrier’s output at the expenses of non-integrating rival shipping firms, the overall social welfare is still improved, which is indicated through the numerical analysis. Therefore, port authorities and government regulators should carefully review the market competition status as well as port expansion plans.

This paper presents a dynamic congestion charging framework that includes a dynamic user equilibrium (DUE) network model to optimize a tolling scheme, whose objective(s) may be determined by the transport planner. The framework presented may be utilised to evaluate potential charging regimes; this paper concentrates on the feasibility of extending the concept of minimal-revenue tolls from the static to time-varying environment. We discuss the limitations in the transference of this optimisation objective and propose a pragmatic approach designed to allow the planner to balance the effect of extracting additional toll revenue against achievable network benefit. We investigate the ability of this framework to incorporate various tolling scenarios and to illustrate the production of low-revenue tolls. The numerical tests use a fixed toll across the entire time period for a range of demand scenarios and a fairly stable tolling solution is observed.

usc Refereed/Peer-reviewed The relationship between container location dispersion for a single loading and the efficiency of quay cranes (QCs) was investigated. For this purpose, a discrete-event-based simulation model was developed to capture the container handling process at a transshipment container terminal. A series of experiments were conducted to illustrate the effects of container location dispersion on the long-term performance of QCs and container allocation. These experiments showed that the container location dispersion has a significant effect on the distribution of loading containers. An optimal choice of container location dispersions can improve the efficiency of the QC and help to manage uncertainty at a lower cost. It is suggested that yard managers consider the workload of each berth when deciding on the location dispersion for a loading service. In addition, it was found that optimal container allocation dispersion reduces the congestion caused by time window conflicts and insufficient available equipment.