## 2 Literature Review  
Virtual reality and augmented reality have the advantage of creating a sense of reality based on a high level of immersion in a virtual space with mixed environments. Based on the size of the VR/AR market in 2021, it is predicted to grow up to 40 times by 2030 [14]. VR/AR has a wide range of applications and high potential for educative purposes. Currently, VR education is partially applied in fields that require hands-on experience because learners can safely and repeatedly practice complex and difficult tasks in virtual environments [15]. In VR, users can immerse themselves in a virtual environment [16] and interact with virtual objects in it. VR provides visual education to make it easier to understand complex content while improving communication efficiency [17]. VR can be subdivided into two types: non-immersive and immersive. Non-immersive VR involves the user partially inserting themselves into a virtual environment by means of a monitor, while immersive VR allows the user to completely insert themselves into the virtual environment using a head-mounted display (HMD) [18]. This study focuses primarily on immersive VR. An HMD blocks out any view of the user's surroundings, which provides the feeling of complete immersion in the virtual environment. The HMD's motion sensor tracks the user's head rotation, allowing them to observe the environment at 360\({}^{\circ}\)[19]. Users can be greatly immersed in the virtual environment in terms of visualization and motion [20]. Given these advantages, research is being conducted to apply safe simulations in fields including building safety education, earthquake education, stroke rehabilitation training, assembly simulation, manufacturing training, and surgical training [21; 22; 23; 24; 25; 26]. VR is also being used in fields that include aerospace, construction, and the military [27]. VR has been proposed as a tool for communication and collaboration during the COVID-19 pandemic, as it enhances the experience of shared remote presence [28, 29]. According to a study by [PERSON] et al., 70% of 298 people surveyed about VR owned a VR device and 60.9% had purchased the device during the pandemic. In addition, 46.0% and 37.2% of the respondents who used VR for work and education, respectively, were identified as using it in addition to watching games and movies [30]. Owing to the communication difficulties involved with COVID-19, the use of immersive technology such as virtual reality for education and training is necessary and has the advantages of flexible hours and training locations [31]. In VR education, students are motivated by their initiative because they learn based on experience [32]. VR training can also avoid problems and accidents that may occur in real training and potentially reduce costs, such as maintenance [33, 34]. Although VR is efficient, as it allows educators to place students in educational environments that are difficult to experience in practice, the adoption of VR education has been limited by the cost of equipment and complexity of implementation [35]. Another major problem is that relatively few classrooms are equipped with VR devices, so there is a lack of educational content that can be utilized. Therefore, educators must create appropriate VR resources and design virtual tools [36, 37]. To construct a VR education environment, it must be integrated well with existing education, and a great deal of effort is required on the part of educators. We investigated other studies using VR in education and observed its positive effects. A study on cardiac anatomy education was conducted by dividing groups into paper, PC, and VR learning methods. As a result, the percentage of correct answers was significantly higher in the VR group, and it was analyzed that VR affected the motivation of the participants [38]. In another study combining engineering and VR education, participants were assigned to a video group and a VR group with a focus on construction education.