The necessity to move to full automation in freight logistics is higher than in passengers to limit the power force and costs and achieve better performance on time and numbers of deliveries. In the future, automation will represent the standard among all carriers
[7]. Consequently, autonomous commercial vehicles such as trucks are expected to be available before autonomous cars for individuals; therefore, autonomous driving in the maritime terminal is expected to materialize soon
[15]. Nevertheless, this expectation could be delayed, and approximation may suffer from different degrees of market penetration. The 100% full automation still represents a far-distant future. Till today, close to a mind-off transition period, concepts of integrating autonomous freight vehicles into traffic systems require separated traffic lines, free route choice or fixed paths in mixed traffic conditions
[16]. Furthermore, safety issues must be quoted as one of the most questioned spots regarding acceptance rates for connectivity. Ports, cities and authorities have a role in developing the context where autonomous and connected vehicles may operate. Then
[16], main challenges to be tackled concern infrastructural requirements, regulations, data protection and communication protocols.
The context of maritime terminals has interested many researchers who focused on several approaches to test and increase performance at the terminal. The approaches vary for the analytical method and the degree of granularity, however discrete-event simulation (DES), in general, has always represented a popular approach among researchers
[17], and many studies focus on its application in solving phenomena related to the management of maritime terminals. In the field of ro-ro terminals (albeit in a much smaller way), discrete-event simulation has been of interest to a wider audience of researchers who dealt with the management of landside and seaside arrivals; to optimize scheduling and allocations problems so long as in a ro-ro terminal, trailer trucks and vehicles cannot usually be stacked for limited spaces and due to the nature of the trips and freight on board. Preston et al.
[18] by means of DES, tested the residual capacity in the e-roll-on-roll-off ferry port located in Dover (UK). The simulation approach was used to organize what-if scenarios under the hypothesis of ordinary disruptions and increasing demand. As KPI, the author utilized both queue time at the gate and pollutant emissions. Iannone et al.
[19] assessed the impact of managerial decisions about loading, unloading and storage allocation. They conducted a discrete-event simulation assessing for each alternative the economic impact of each alternative and pollutant emissions. Kaceli
[20] used simulation in the contest of a ro-ro terminal to predict planning scenarios and determine the necessary infrastructural needs. Even more, as stated by Ozkan et al.
[21], ro-ro terminal operations specifically needed a focus on timetable coordination and scheduling, thus integrating different levels of communication. As a consequence of this, at least three variables of interest resulted: the number of trucks arriving at terminals, the distance between terminals and Ro-Ro ship capacity. Abourraja et al.
[22][23] discussed the problem of flexibility in decision-making in the context of a ro-ro terminal. In it, they proposed a generic framework to be used as a tool for specific decision support models at the terminal. The assessing method was addressed utilizing different KPIs, such as workload, time and distance. Park et al.
[24] proposed an automated solution with the use of Automatic Guided Vehicles (AVG) for a ro-ro terminal. The model analyzed the economic benefits of introducing AVGs, thus assessing the achieved level of productivity. Varying the number of available AVGs, the queue time was used as KPI to optimize the number of vehicles and average waiting time. Muravev et al.
[25] mainly focused on DES as an operative tool to test the effectiveness of the proposed solution. They modelled the operation for a ro-ro terminal using two different software packages (Arena and AnyLogic) and considered model scalability. Finally, Sharif et al.
[26] focused their work on environmental sustainability linked to the queuing time at the maritime port. The experimental analyses were carried out by means of an agent-based approach to reproduce daily activities in the terminal areas. Output stated that live information and operation coordination and routing info might reduce the effects of congestion. Parola and Sciomachen
[27] focused on logistics chain sustainability and evaluated the performance of a multimodal container port. The simulation problem was implemented with the aim of measuring congestion phenomena in the road and rail network. Coordination among the different stakeholders resulted in being the main goal to pursue to favour a modal re-equilibrium, whereas van Vianen et al.
[28], considering the case of intermodal transport, developed a DES model to schedule stackers’ operations (for example, assigning the stacker to a ship or to a train). Handling and operative time were used as KPI to assess the achieved performance with a specific layout solution.
On the other hand, container ports, in general, have always represented the most interesting field of application due to the higher level of transport demand and daily operation. In this sense, truck control arrivals and the management of yard slot allocations were widely debated among academics. For example, Jovanocic
[29] designed a TAS in the context of two container ports (Los Angels and Seattle (USA). A scheduling problem is defined in it, and the corresponding integer programming model is developed from the truck driver’s perspective to increase user satisfaction. Similarly, Azab et al.
[30] developed a TAS to achieve a higher level of workload. The proposed algorithm evaluated the best truck arrivals schedule to minimize the total costs of both the terminal and the trucking companies. Performances were tested by measuring truck turnaround time and length of queues. Furthermore, Neagoe et al.
[31] used a DES, developed in Python, to simulate and to assess the introduction of a TAS in a container port located in Australia. As output, the impacts of congestion (truck queue and emissions), also concerning the increasing of terminal activities, were measured. The performance indicators were multiple (truck turn-around times, waiting times, turnaround time reliability and engine idling emissions). Nadi et al.
[32] introduced an advisory-based time slot management system (TSMS) to control truck arrivals. In it, discrete choice modelling is used to analyze the expectations and preferences of the truck operating companies. Then stated preferences are used to shift track arrival in the off-peak period. The DES is applied to assess the effectiveness of the designed TSMS. Srisurin et al.
[33] simulated daily activities within the terminal area to assess terminal capacity in terms of handling, allocation and where house options. Performance was tested under six scenarios whose nature varies from tactical measures to planning policies and solutions. A further detail of granularity was of interest to Schoroer et al.
[34], who developed an Inter Terminal Transport system in the terminal of Rotterdam accounting for different solutions and machines. Both priority and first-in-first-out (FIFO) strategies were tested during the simulation, and mean delay per ride was used as KPI to test the effectiveness of the configuration.
Infrastructural planning and terminal capacity are crucial topics, and several researchers focused on productivity. Rusca et al.
[35] utilized discrete-event simulation for investigating performance in a container port through berthing capacity and for operative planning of logistic processes under different arrivals flows. Carteni and De Luca
[36] addressed port container performance through simulation of the handling activities. Results validation was carried out for short- and long-term planning horizons by evaluating local and global performance indicators. Cimpeanu et al.
[37] introduced DES to predict and evaluate long-term planning performance by assessing berth occupancy and financial costs of the investment for a container port in Ireland. Finally, Li et al.
[38] dealt with the disruption for both land and sea-side. The resilience of the terminal is addressed in terms of total truck waiting time and idling emissions. DES was conducted to test achieved performance in terms of sensitivity analysis, whereas Alvarez et al.
[39] obtained progressive planning and decisions on how to allocate berth space by assessing the potential benefits of new berthing policies. The DES was used to model the environment and subsystem characteristics, operations and performance indicators (for the land-side equipment, contractual agreements and associated penalties and berthing policies). Triska et al.
[40] also dealt with port capacity assessment. The simulation was carried out with the Monte Carlo technique and tested in a DES model. The authors studied economic and operational criteria for the port capacity (berths, storage slots and truck gates). The gate performance and the optimum number of the server were at the basis of the works developed by Guan and Liu
[41][42]. The paper applied a multi-server queuing model to analyze marine terminal gate congestion and an optimization model was developed to balance gate operation costs and truckers’ waiting time. The introduction for a truck appointment system resulted as the best option to introduce.
An agent-based approach at the basis of the planning and capacity of the system for both Assumma and Vitetta
[43] who simulated loading and unloading operations and Fleming et al.
[44] who focused on pooled queue strategies. Finally, concerning traffic at the maritime port, several researchers focus on TAS only simulating terminal process recurring to the Genetic Algorithm (GA) and the Queue theory
[45][46][47][48][49].
Table 1 synthetically reports main feature of the previous work concerning performance and simulation methods for both ro-ro and container terminals.