## 2 State of the Art
### Operations in Ro-Ro Terminals  
Roll-on/Roll-off (Ro-Ro) operations, while efficient for transporting vehicles and heavy machinery, face numerous challenges due to logistical complexity and limitations in port infrastructure. These issues not only affect the efficiency of operations but also have broader economic and environmental implications. Below is a detailed analysis of the key operational challenges faced by Ro-Ro terminals. One of the most pressing issues in Ro-Ro terminals is vehicular congestion, which creates bottlenecks during loading and unloading operations. This congestion often arises from poor traffic management planning within the terminal and insufficient coordination among ships, transporters, and port personnel. The resulting delays significantly increase waiting times and operational costs, as noted by studies on port traffic management [21]. A lack of synchronization between ship schedules and vehicle movements frequently disrupts operations. The limited use of advanced technologies for real-time tracking and management exacerbates this issue. Moreover, poor communication between key stakeholders, including port operators, shipping lines, and transporters, leads to logistical delays and reduced efficiency [22]. This inefficiency undermines the competitive edge of Ro-Ro terminals in global logistics networks. The high density of vehicles and machinery in Ro-Ro terminals increases the likelihood of accidents, posing risks to personnel and equipment. Contributing factors include insufficient real-time monitoring systems, inadequate staff training, and a lack of clear signage or guidance systems. Studies have shown that improving safety protocols and integrating automation can significantly mitigate these risks [23]. Vehicles often experience prolonged waiting periods for embarkation or disembarkation. This issue is largely attributed to slow, manual processes for inventory and document management, as well as limited terminal capacity. Extended waiting times not only increase costs for transporters and operators but also lead to customer dissatisfaction, as highlighted in recent analyses of Ro-Ro operations [24]. Many Ro-Ro terminals struggle with space limitations for storing and organizing vehicles. The lack of optimized strategies for vehicle placement and infrastructure constraints reduces the operational capacity of the port. Effective use of space has been identified as a critical factor in enhancing the efficiency of Ro-Ro terminals [25]. Inefficient operations lead to increased costs associated with fuel consumption, labor, and maintenance. The continued reliance on manual processes and the limited adoption of automation or IoT technologies are major contributing factors. Addressing these inefficiencies is essential for improving the financial viability of Ro-Ro terminals [26]. Ro-Ro operations are significant contributors to CO\({}_{2}\) emissions due to prolonged waiting times with idling engines and the extensive use of machinery. The absence of sustainable strategies for managing operations further exacerbates this issue. Implementing eco-friendly practices and reducing idle times have been identified as key solutions for minimizing the environmental footprint of Ro-Ro terminals [27]. Despite the potential benefits, many Ro-Ro terminals have not yet implemented advanced technologies such as IoT or IoV. High initial investments and a lack of technical expertise often deter adoption. This technological gap places Ro-Ro terminals at a competitive disadvantage compared to more advanced ports [6]. Fluctuations in the volume of vehicles to be transported present significant planning challenges for Ro-Ro terminals. These fluctuations are driven by seasonal factors and changes in customer demand or trade routes. Addressing this variability requires flexible operational strategies and predictive planning models [6; 28]. Operational practices in Ro-Ro terminals vary significantly across countries and regions, complicating efforts to standardize processes.