NavalTrans Model

NavalTrans is an agent-based model, and it is developed on Eclipse, an open-source integrated development environment (IDE), using Repast J agent modelling toolkit. An instance of the model is composed of two main components; the model code, and the parameter file. The model code depicts the actions of the actors, relations between system elements, and general developments in the system. In other words, it depicts the structure of the model. The parameter file is a conventional MS Excel file, which contains the initial values of the model parameters that are needed to create an instance of the model. This architecture brings ease and flexibility to experimentation with NavalTrans: no programming skills are required in order to create different instances of the model and conduct experiments, since creating a new parameter file suffices for the task.

The model covers 2 naval transportation options (i.e. wind-powered sail-ships, and steam-powered steam-ships), and the behaviour of 9 actor groups. 7 of these groups are practitioner/user type of actors that constitute the demand-side of the transportation system. The remaining two actor groups represent the provision side of the system; i.e. provider-type actors.

In the following section, we will first introduce the objects, which are the basic pieces of the model. Following that, the behaviour of the overall model, as well as the objects will be discussed mainly using pseudocodes[1] and time-sequence diagrams[2]. When necessary, implemented functional relationships will be introduced in detail.