**4.2 Element 2: functionalities**

Functionalities, in the context of this study, refer to the features that libraries receive through the adoption and use of IoT-based seat occupancy and reservation


#### **Table 4.** *Library seat occupancy and reservation systems benefits and functionalities.*

*A Systematic Review on IoT-Based Smart Technologies for Seat Occupancy and Reservation… DOI: http://dx.doi.org/10.5772/intechopen.113329*

systems. The systems allow library users to check the status of the library anywhere and at any time, utilizing their mobile phones or any device with Internet access reducing manual efforts. They ensure that reserved seats in the library study area are secured and that users can reserve seat according to their preference. Everyone is allowed to view the library status and check the availability of seats, but only registered students are allowed to reserve their library seats [3, 9, 53]. These systems act as a medium between the library users and the library staff (librarian). The library staff would have the ability register new library users, view seat occupancy status and produce detailed reports (see **Table 4**).

#### **4.3 Element 3: methodologies**

The IoT-based seat occupation and reservation systems are discussed in detail in this Chapter, illustrating various IoT-based seat occupation and reservation systems using different IoT technologies. These IoT methodologies include LBPH face recognition algorithm, Thing Speak channel, Up-squared board, ultrasonic sensor, Thing Speak cloud, SQLite Studio database, Python, RFID, FSR, Raspberry-Pi, Wi-Fi Module, Node MCU, PHP API and capacitance sensor chip. To establish the seat occupancy and rank the options, some approaches used a single procedure, such as the capacitance sensor technology. A combination of methods, including RFID and FSR, were used by other authors to identify the seat occupancy. To find out how many seats were occupied, researchers used a face recognition system, an ultrasonic sensor, and other tools. The gap in the literature is discussed and the shortcomings of these IoT-based reservation and seat occupation systems are highlighted. The adoption of mixed methods enhances performance. Other studies employed RFID and FSR. While FSR detects seat occupancy and transmits the information to the network layer, RFID is responsible for identifying authorized users who made a specific seat reservation (**Table 5**).
