## 7 Disaster Management  
SDG 11.5 indicates that \"By 2030, significantly reduce the number of deaths and the number of people affected and substantially decrease the direct economic losses relative to global gross domestic product caused by disasters, including water-related disasters, with a focus on protecting the poor and people in vulnerable situations\" ([[https://sdgs.un.org/goals/goal11#targets_and_indicators](https://sdgs.un.org/goals/goal11#targets_and_indicators)]([https://sdgs.un.org/goals/goal11#targets_and_indicators](https://sdgs.un.org/goals/goal11#targets_and_indicators)), accessed on 10 February 2024). The primary function of the IoT in urban disaster management is predisaster prediction.  
In predisaster monitoring, people use IoT systems for structural health monitoring and crowd monitoring. [PERSON] et al. [101] discussed two IoT structural monitoring systems in the Prague Metro and London Underground. They used crackmeters (i.e., linear potentiometric displacement transducers), inclinometers (Model: SCA103T-D04), and humidity and temperature sensors (Model: Sensirion SHT11). They used the Crossbow MIB600 (XMesh routing protocol) as a gateway to collect the sensor-generated data and then transmit them to a single computer board through an Ethernet cable. The single computer board then transmits the data to a database through GPRS. [PERSON] et al. [102] deployed an IoT-based structural health monitoring system for the new headquarters of the Shenzhen Stock Exchange in Shenzhen City. Since this building is one of the largest cantilever structures worldwide, it is important to measure the strain and deflection of the cantilever structure. The sensors in the system included a vibrating-wire strain gauge, temperature sensor, and accelerometer. The system also had a vision-based displacement tracking system. The communication technology is WLAN. [PERSON] et al. [103] used a vibrating-wire strain and temperature sensor, a three-axis digital output linear accelerometer (i.e., Model LLS3 LV02 DQ), a wind speed sensor, and a displacement sensor to develop an IoT-based structural health monitoring system for the National Stadium in China. The vibrating-wire strain and temperature sensor integrated a digital temperature chip (i.e., Model DS18B20). They used IEEE 802.15.4/ZigBee for communication. [PERSON] et al. [104] proposed a structural health monitoring IoT system to monitor section convergence, joint tensioning, and water seepage in the segmental lining of shield tunnels with light-emitting diodes to indicate different risk levels for workers on site, and finally, an elasticity-based analytical model for designing rehabilitation strategies. Their IoT system included a tilt sensor, crack sensor, and seepage sensor. They used Zigbee and WiFi as communication protocols. [PERSON] [105] deployed an IoT-based structural health monitoring system in at a concrete bridge in Bangkok City. The system is on a Microstrain platform. This system used an applied strain gauge as a sensor to measure bending strain. The communication protocol is Lossless Extended Range Synchronized. They adopted real-time stream processing and artificial neural network techniques in data analysis. For an excepted structural health monitoring system, [PERSON] [106] used a deep learning algorithm to process crowd data and predict the number of people at Castelldefels Beach in Barcelona City, which is important for rescue operations at the beach. The crowd data are generated by cameras. They used \"CountThings\" as image recognition software. In addition, [PERSON] et al. [107] proposed a blockchain-based IoT system for structural health that provides verification of monitoring privileges, generates anomaly alerts, ensures data invariance, resists attacks, and allows for traceability queries.