### Literature Review on Available Solutions
\begin{table}
\begin{tabular}{c c c} \hline \hline
**Reference** & **Main Characteristics** & **Limitations** \\ \hline \multirow{5}{*}{[28]} & DECATASTROPHIZE (a.k.a., DECAT) platform that aims at managing disasters or multiple and/or simultaneous natural and man-made hazards by means of a Geospatial Early-warning Decision Support System (GE-DSS) that allows early warning, decision making, rapid mapping, impacts assessment and mitigation, and geospatial data/information dissemination. & Does not consider overcrowding. \\ \hline \multirow{5}{*}{[29]} & A web platform developed by the Emergency and Security Coordinating Centre to improve the decision making process of the Canary Islands’ Authorities, which provides a geographical and temporal incident distribution and which is able to forecast and classify incidents. & Emergency and security incident distribution only. \\ \cline{2-3}  & A Building Information Modeling (BIM)-based platform that was designed for building fire emergency management in a dynamic way, i.e., using building users’ behavior decisions (e.g., escape, wait for rescue, and fire extinguishing) and both fire and users’ positions, which plans action routes and provides visual route guidance. & Buildings only; Fire emergency only; Does not consider not consider overcrowding. \\ \hline \multirow{5}{*}{[31]} & A smartphone-based platform for city-wide crowd management (through a “heat map-like” system for a real-time overview of the spatiotemporal distribution of crowds in given areas and through specific messaging for real-time, smart, adaptive emergency response and evacuation strategies), which aims at having smart crowds in smart cities and which was used in at least three European countries (UK, Netherlands, Switzerland). & Smartphones as sensors; Does not consider emergency detection. \\ \hline \multirow{5}{*}{[32]} & A cloud-based architecture for emergency management and first-responders localization (landmark-based and landmark-free), which aims at supporting coordinated emergency management in smart cities based on the localization of first responders during crisis events. & Localization of first responders only. \\ \hline \multirow{5}{*}{[33]} & Smart disaster management system for transportation applications in smart cities, which gathers information from multiple sources and locations (using VAENTS, i.e., Vehicular Ad hoc Networks, such as Vehicle-to-Vehicle, V2V, Vehicle-to-Infrastructure, V2I, or smartphones or other technologies), detects the point of incidence, makes strategies and decisions (using, e.g., high-performance computing, HPC), and propagates the information to vehicles and other nodes in real time. & Traffic incident only. \\ \cline{1-1} \cline{2-3}  & Traffic incident only. \\ \hline \hline \end{tabular}
\end{table} 
Table 2: _Cont._architecture, optimized in real time, to obtain smart buildings [43]; 3) a recommendation system based on the concept of Social IoT (SIoT), i.e., use and reuse data generated by various IoT applications, and adapt the services provided by the single IoT system, to improve the user experience [44]. Based on the literature, different strategies can be adopted to derive/recognize safe routes and assembly points. Traditionally, the problems above can be solved using Shortest Path Finding (SPF) algorithms that belong to the mathematical field of Combinatorial Optimization. Noteworthy examples are: (1) [PERSON]'s algorithm, which can be used to derive the Minimum Spanning Tree (MST; i.e., a tree diagram without circles) [45]; and (2) the [PERSON]'s and the A* algorithms, which allow one to derive the shortest path between two points [46]. In the Matlab environment, it is possible to find different tools (e.g., \"shortestpath\" and \"digraph\") that allow one to solve this problem [47]. This study also refers to a bidirectional exchange of information between a platform and its users, which can be satisfied using NFC technology [48].