## 2 Related Works
### Blood Bank Systems  
Through literature studies, some researchers considered how the lack of blood bank automated management systems and a paper file management system make the retrieval and processing of data slow [31]. This results in a longer wait time, especially in organ donation cases, most often involving the heart, liver, and kidney, with organs going unused owing to mismanagement or because the organ has outlived its practical shelf life; this delay may lead to death [6]. There is no database of blood donors for use in a crisis because Excel is used as a database in medical centers, resulting in a lack of credibility. There is an absence of public awareness regarding blood donation because of the lack of technology for communication about donation [32; 33]. In addition, poor management leads to poor communication between the donors and medical centers, leading to lost blood bags and scarcity of specific blood groups [4]. Some people have lost their relatives or friends because blood bank systems do not exist in rural areas [21]. The research in [3] utilized a smartphone app to find and locate a particular blood group. The mobile app connects donors and persons in need via Android Studio, Kotlin, and the Firebase Realtime Time Database by giving detailed information that enables the needy to select the nearest and most appropriate donor. The authors of [21] used a cloud-based blood bank system to provide blood in times of need with an Android app and GPS to track nearby hospitals or blood banks, and NoSQL was used to build and implement the databases since it provides a technique for data storage and retrieval. Some researchers proposed both Web- and mobile-based applications for improved and more efficient blood bank information handling and to establish a direct connection between the donor and the beneficiary [31; 33]. However, despite the efforts made to design applications based on smartphones, the Web, and other technologies, these studies did not involve Internet of Things technologies in the development of the blood bank, monitoring, and tracking systems. The Internet of Things (IoT) has attracted the interest of researchers and engineers worldwide as a vital component of the next generation of intelligent information technology [34] which can contribute to improving people's lives. It can also help to save time and money by making suitable decisions quickly [25]. The medical sector is a fundamental area in which to implement IoT technologies, and it is the most popular area for IoT-enabled applications [35]. IoT devices are shared via a Web server, and various sensors, which are easily customizable and have a low cost, are used to collect data, as well as the IoT system, which can be linked to mobile applications [18]. Smartphones and other IoT devices are critical for extending and utilizing this new IoT domain [35]. To enhance blood bank systems, a practical method for an intelligent blood management system was introduced in [36] based on new IoT techniques, Web services, and mobile apps that improve the communication between different blood banks and attempt to solve the weaknesses in management and awareness, especially in traditional systems. The study in [37] provided a total solution by designing an intelligent system that improves automation via the IoT and connects blood banks, donors, and patients when donating and supplying blood. It can be used to alert the nearest blood banks in emergencies to ensure the availability of safe blood for the needy with minimal effort via GPS data technics. In [32], a smart, IoT-based network and an intelligent app for blood banks, MOH hospitals, and donors were improved. The system includes Web and mobile apps. Future Internet of Things technology will provide smart devices with environmental sensors and reinforce next-generation networking and radio frequency identification technology (RFID).