## 2 Materials and Methods  
### Materials  
#### 2.1.1 IoT: Definition and Evolution  
IoT was introduced in 1999 by [PERSON] and is the network that connects objects in the physical world of the Internet, allowing communication between them, collecting and exchanging data between them and people in order to achieve goals in different fields and applications [20]. Developed based on RFID technology by MIT's Auto-ID Center, IoT has received several definitions: (1) focusing on smart infrastructure with Radio Frequency Identification (RFID) technology [21], (2) ubiquitous connection [22], (3) dynamic global network infrastructure with the identification of physical and virtual things [23], (4) a network containing all smart devices with a kind of detection mechanism that can communicate via the Internet with other smart or cloud devices [24]. Smart devices are those devices that have built-in systems with Internet connectivity, being equipped with a microcontroller, sensors and actuators. The sensors receive the real-world data, the microcontroller processes this data and the actuators create the events based on them. These devices are self-configured and can be controlled remotely [25; 26; 27]. IoT components consist of: (1) sensors, RFID technology and near field communication (NFC) with short-term wireless data collection technologies, (2) wireless or wired Internet networks for data transmission, and (3) applications of services for processing, analyzing and managing transmitted data [28]. In other words, IoT is a vast computing network that connects wireless sensors to application services over the Internet. Whether we are talking about employees or managers, studies on the behavior of users of IoT solutions are limited in the academic literature and are still in an early stage [29]. Adopting new technology can bring benefits (convenience, speed in decision making) but also negative effects (anxiety or technological stress) to its users [30]. Thus, three types of paradoxes with double impact on users of computer products were identified: (1) control/chaos; (2) meeting needs/creating needs; (3) freedom enslavement [31; 32; 33]. The increase in the number of users (corporations, companies, SMEs, individuals) who use IoT can be explained by the many benefits it offers such as: (1) improving the customer experience; (2) improving efficiency; (3) access to data/collection of new data; (4) reduction of labor cost/actual costs; (5) connectivity; (6) saving time; (7) a new positioning at the business level [34]. Although the benefits to users of IoT applications are obvious, there are a number of concerns about: (1) complexity, (2) dependence on other IoT applications, (3) business models used, (4) society, (5) regulatory standards and (6) data security/protection (unauthorized access to personal information and risks of hacking on IoT applications) leading to positive factors that promote IoT use and negative factors that prevent IoT use [34; 35]. 1.2 Unified Theory for Acceptance and Use of Technology (UTAUT): Importance, Advantages and Limitations  
The clearest highlighting of the relationships between the degree of acceptance of information technology and IoT by employees, employers or managers and their intention to use information technology is achieved using the Unified Theory for Acceptance and Use of Technology (UTAUT). Based on the general model of technology adoption, the UTAUT model was developed as an integration of previous research models in the field of technology acceptance [36]. This model has incorporated several theories such as: rational action theory (TRA) [37], acceptance model technology (TAM) [38], TAM 2 [39], motivational model (MM) [40], planned behavioral theory [41], C-TAM-CTB model, computer use model (MPCU) [42], social cognitive theory (SCT) [43] and the theory of innovative diffusion (IDT) [44].