# Theoretical Framework (Module) for Short-Sea Shipping System Evaluation
## 2 SSS Situation and Analysis of the Literature  
Short-sea shipping is an important part of the transport system and is mostly focused on cargo transportation between ports, with the aim of optimizing the legal framework between countries and minimizing the optimization of ship and cargo procedures in ports [1]. Due to the fact that there are no economic borders in the European Union, there is an opportunity to minimize the number of documents and procedures for vehicles and cargo transported between different places in the EU [1; 2; 3]. The International Maritime Organization (IMO) Convention on Procedures provides for the main ship and cargo documents [8], and the legal hurdles of SSS can be resolved using these conventions. At the same time, using different modes of transport allows one to search for optimal solutions depending on the conditions of cargo transportation and various restrictions [9]. In most cases, cargo is transported between the main regions of the world economy by ocean routes between the main ports (hubs), and then feeder or tramp transportation is most often used between the main and final or so-called feeder ports, using the recognized legal basis of the FAL Convention [8]. It is also necessary to note that some countries have enacted additional legal acts, which sometimes differ significantly from the system adopted by the FAL Convention; therefore, one of the main goals of the SSS system is to unify different legal bases for cargo transportation of countries, regardless of whether there are economic borders between the ports of cargo transportation or not, as, for example, in the EU area [2; 9]. The SSS system is one of the essential ways to optimize cargo transportation and achieve sustainability of transportation [3]. SSS is analyzed in various sources which study various elements of the transport chain to adapt them to the development of new transport systems [9; 10]. The main goal of transport systems, including SSS, is fast, safe delivery of goods between ports, while optimizing transportation costs [11]. Fast delivery of goods between ports is associated with the ability to use the advantages of linear shipping if there are shipping lines between ports [12; 13; 14]. If there are no shipping lines between specific ports, then it is very important to compare the possibilities of transporting goods by different modes of transport, using tramp shipping by ships and other transport systems [14]. In the SSS system, ports occupy a special place, and loading and other logistics operations are carried out there to minimize the time of ship-loading operations, since with relatively short transportation distances, the passage of ships between ports takes relatively little time, and in some cases, loading operations in ports are carried out in close proximity to ship navigation; i.e., the efficiency of transportation by ships decreases. Optimization of port operations by minimizing the time of ship processing in ports is one of the essential ways to increase the efficiency of transport and logistics chains [2; 4; 7; 14]. By minimizing the handling of ship formalities in ports through using the capabilities of the SSS system, conditions arise to better concentrate on cargo assembly in port terminals, similar to logistics centers [5; 7], since the SSS system is associated with linear shipping, i.e., the creation and adherence to specific ship sailing schedules and the publication of basic transportation prices [11]. By optimizing transportation processes based on SSS, energy costs for transporting the same amount of cargo are reduced, and environmental impact is reduced [15; 16; 17; 18]. Short-sea shipping has a significant impact on various regions of the world by improving cargo and passenger service [13; 19; 20; 21].