# UAV-Enabled Mobile Edge-Computing for IoT Based on AI: A Comprehensive Review
## 2 UAV System Model
### UAV Applications  
Despite the strict restrictions on the civilian usage of drones, they play a promotional role in providing many facilities and enhancements in different application scenarios. Moreover, with the rapid development and emergence of new communication paradigms to achieve global connectivity, drones will positively facilitate many intelligent features. Table 3 shows a list of UAV applications in various domains, their advantages and disadvantages, and current research challenges. * Agriculture:  
Drones have been used to monitor large agricultural fields to detect specific diseases that threaten the quality of plants at an early stage. The implemented system can predict farm diseases in real-time by exploiting image processing and AI classification based on IoT architecture, using real-time data acquisition [39]. In ref. [40], the authors have proposed an architecture combining UAVs and wireless sensor networks (WSNs) with IoT approaches to provide precise ecological agriculture. Another architecture for crop mapping monitoring and disease assessment-based satellite imagery using the DL approach has been proposed to analyze the images acquired through UAV airborne multispectral sensors [41]. Additionally, UAVs can efficiently enhance the productivity of farming activities, as referenced in [42; 43; 44]. In addition, UAVs play an exciting role in crop monitoring by facilitating many tasks previously restricted to the laborer and farmer [45; 46; 47]. * Industry 4.0:  
The increasing demand for fast and low-cost productivity has encouraged the industrial and research communities to incorporate robotics into the industrial process. UAVs have recently attracted the attention of industrial solution providers in response to the increased need for productivity; for instance, the authors proposed an industrial IoT-based system that collects data by a UAV camera and sends it to a cloud server for processing [48]. The design aims to monitor the industrial zone to prevent undesirable incidents in the production process, relying on the robust intelligence of computer vision (CV) approaches [49; 50]. The mining industry has also increased the level of interest in drones for 3D mapping, mine safety, and mine management [51]. * Environment:  
UAVs are being adopted as a means to monitor and survey various environmental areas. They can be used for the monitoring and data aggregation of archeological sites. For example, the authors of [52] have reported that UAVs can present accurate and precise images of the studied archeological space, compared to terrestrial measurements. UAV  
Figure 3: UAV-enabled intelligent services in IoT. technologies can also be deployed in ecological monitoring systems to track wildlife in heterogeneous territories and topographically challenging areas as a supporting platform for traditional techniques [53]. Besides, this technology may facilitate geological researchers when collecting remote data about many species and animals [54]. Moreover, the authors of [55] proposed an intelligent model based on UAV, dedicated to monitoring several types of plants using the latest computer vision algorithms and cloud computing technologies. UAVs are also used to track wild animals over large areas [56]. * Health and emergency:  
Drones can offer several benefits for public health emergencies, for instance, tackling epidemics and contagious diseases such as COVID-19. For instance, during the COVID-19 pandemic, some governments and countries adopted drones to survey the rapid spread of the virus, diagnose patients, and then predict the mortality risk factor by applying AI approaches to the collected data. The drones have been used to observe crowds, broadcast critical public announcements and information, spray disinfectants, and carry out extensive temperature measurements in several residential areas [57]. Additionally, the lifeguard community uses UAVs for search and rescue missions requiring rapid intervention.