An Effect of Sharing Damaged Road Information via Heterogeneous DTN on Evacuation

Abstract

Sharing the information on damaged roads is a critical matter in disaster evacuation. We aim to develop a heterogeneous DTN based-disaster information sharing system, which uses both short-range wideband media (e.g., Wi-Fi) and long-range narrowband media (e.g., LoRa) to share disaster information even if communication infrastructures are damaged. In the system, evacuees carry a Wi-Fi mobile device, and fixed relay nodes and devices at disaster headquarters are equipped with Wi-Fi and LoRa. We investigated the influence of the DTN on evacuees’ behavior by using the cellular automaton-based mobility and communication simulation model. The results show that “leaving behind phenomena”, in which evacuees who hold the damaged road information (early comers) leave the damaged road before evacuees who have not obtained the damaged road information (latecomers) come to the vicinity of the damaged road occur. We also derived a strategy for the effective placement of fixed relay nodes to avoid leaving behind phenomena based on the simulation results and confirmed the strategy’s effectiveness.