Mathematical modeling of transport and logistics infrastructure for the post-war reconstruction of Ukraine

The paper is dedicated to addressing the scientific and practical task of expanding the utilization of inland water transport and increasing the variety of transport and logistic alternatives with the aim of creating a more efficient and resilient logistics system in Ukraine.Based on the analysis of the state of river ports, unloading terminals, and docks within the overall river infrastructure of Ukraine and their connectivity to land transport networks, ports were selected that could be used for establishing logistic zones based on them. An assessment of the level of transport accessibility of ports in the Dnipro, Danube, and Southern Bug river basins was carried out, and the corresponding graph was constructed. The Gephi software, which has open-source code for visualizing and analyzing graphs of large networks, was used to construct the graph. Assessments of the accessibility level of the port network were also conducted using the Kenig number and relative indicators: Bavelash and Boshe indexes.The research results have shown that in conditions of a state of war, occupation of maritime space, and destruction of a significant amount of the country's infrastructure, there is a necessity to create a network model of transport logistics using navigable sections of the Dnipro and Southern Bug rivers and the "Danube – Black Sea" navigation route to ensure national security and sustainable functioning of Ukraine's economy. There is a need to expand this system further and connect it to the Rhine-Danube corridor. To address security challenges, it is necessary to establish a transport-logistics system that simultaneously utilizes inland waterways, railway, and road transport infrastructure.