As the educational environment is rapidly evolving due to the Fourth Industrial Revolution and COVID-19, online education, which formerly was mainly practiced in speci-alized schools such as cyber universities [1,2], is now being employed by many universities through a mix of in-person and non-face-to-face classes. This transition has notably af-fected nursing education, where the necessity for both the-oretical and practical learning is paramount; in particular, online courses have led to reduced learning outcomes due to less direct interaction and engagement between teachers and students [3-5]. In non-face-to-face online education in learner-centered environments, learning flow - perceiving learning as a meaningful challenge, believing in one's abilities, and being fully immersed and willing to engage in difficult tasks-is essential for learning outcomes [6,7]. Learning flow is critical because it increases motivation and the likelihood of success [8]. Similarly, learning motivation is essential for persistence in studies and influences performance-related factors, including initiation, continuation, goal setting, and outcomes [9]. In nursing education, self-motivation and autonomous learning are crucial, and they involve choosing one's learning path and self-directing behavior [10]. Self-determination and intrinsic motivation are linked to greater persistence and academic achievement [11]. Therefore, examining the relationship between learning flow and self-determined learning motivation is key to advancing academic achievement and nursing competency. In online learning, academic emotion regulation is vital as it helps learners manage their emotions, which vary in their effects on learning outcomes [12]. Positive emotions can enhance voluntary effort, while un-pleasant emotions may lead to motivational loss [13]. Effective emotion regulation is associated with better cognitive processing, task performance, and motivation control, pre-dicting academic success [12,14,15]. Therefore, learners’ emotional regulation is critical to the academic process [14]. Academic emotion regulation is closely related to high-level cognitive processing, task performance, and motivation control. It has a direct and indirect influence on academic achievement and is a predictor of successful academic performance [12]. Proficient students exhibit strong problem-solving abilities and accomplish their goals [15]. Therefore, challenges emerge in achieving learning outcomes due to reduced direct contact with instructors and lack of interaction owing to online classes [3,4]. In online classes, we aim to identify the mediating effect of academic emotion regulation to promote learners’ active participation and cognitive function so they can become more self-determined in class and experience learning flow in relation to motivation. Immersion is essential for online real-time classes to lead to learning outcomes. Learning immersion is a pleasant state in which one is completely in-volved in educational activities and feels challenged and accomplished in meeting difficult tasks, thereby improving outcomes [8]. Research shows that self-determined learning motivation directly influences learning flow and positively affects learning-related variables [11,16,17]. Academic emotion regulation also, directly and indirectly, impacts learning flow [18], with self-determined learning motivation mediating this relationship in the perceived teacher-stu-dent dynamic [19]. As the paradigm of nursing education is becoming performance-oriented and rapidly shifting to an online education environment, learning engagement has been studied as a critical variable. For example, learning engagement is examined as a mediator in the effects of online real-time classes on performance-oriented learning outcomes [20] and those of self-friendship among nursing students who take online classes [21]. However, the mediating effect of academic emotion regulation in self-de-termined learning motivation on engagement in nursing students, which is necessary for enhancing their learning capabilities and performance-based education, has not been studied. This study seeks to enhance nursing students’ learning capabilities and performance-based outcomes in online education by exploring the impact of self-determined learning motivation on learning flow and the mediating role of academic emotion regulation. The goal is to provide data to inform the development of teaching methods and educational strategies that foster self-de-termined learning motivation, emotion regulation skills, and improved learning outcomes. This study aims to identify nursing students’ self-determined learning motivation and flow. Furthermore, it examines the mediating effect of academic emotion regulation on the relationship between self-determined learning motivation and flow.

This study examined the degree of self-determined learning motivation and flow and academic emotion regulation in nursing students related to online teaching methods. It also investigated the mediating effect of academic emotion regulation on self-determined learning motivation and learning flow. The goal was to propose an educational plan to enhance students’ learning flow. In this study, the score for self-determined learning motivation was 2.91, which aligns with Lee and Han's research [27]. Their focus was on the academic adjustment of in-dividual nursing students, yielding an average score of 3.07. To enhance nursing students’ self-determined learning motivation, instructors must increase learners’ autonomy. This adjustment requires attitudes and stances that respect learners’ opinions and ideas concerning the learning environment and teaching methods. They should support learners’ autonomy as much as possible [24]. Therefore, based on continuous interaction with students, professors should enable students to be supporters and advi-sors for academic, career, and other issues, such as adjusting to the course and developing and applying comparative programs promoting self-control and autonomy. The academic emotion regulation score was 3.45 (79.59), com-pared to 3.37 in Noh and Kim's [28] study targeting nursing students and 80.64 in Tak and Cho's [29] research. There was no significant difference in academic emotion between Tak and Cho's [29] study and ours. We discovered that academic emotion regulation influences adaptation to college life [29]. Learners who concentrate on self-development, academic improvement, and understanding are more self-aware and better equipped to regulate their emotions [29]. Therefore, academic emotion regulation is a variable that enhances learning. Controlling academic emotions is necessary for nursing students who integrate theory and clinical practice. For this reason, various academic emotion regulation programs should be developed and included as part of courses and curricula. Nursing students, distinct from their counterparts in other departments, must navigate the stress and challenge of integrating theory with clinical practice. As such, academic emotion regulation can profoundly impact their learning progress and comprehension. Consequently, implementing support strategies that consider emotional aspects and enables nursing students to manage their academic emotions more effectively. To achieve this, developing and applying various programs for academic emotion regulation in extracurricular or curricular courses is necessary. These programs will empower learners to succeed by fostering positive attitudes toward learning. The learning flow score was 3.31, mirroring the findings of Kim and Park [30]. Learning commitment refers to the belief in one's ability to perform a task [11]. Consequently, during COVID-19, as many students were engaging in distance learning, implementing an educational program that promotes learning flow and enables nursing students to perform tasks independently was crucial. Significant findings were obtained for learning flow related to religion, department satisfaction, and GPA. The post-hoc analysis revealed that department satisfaction was above average. GPAs between 3.0 and 4.0 were more common than lower ones. Furthermore, GPAs of 4.0 were more common than those ranging from 3.0 to 4.0. Religion also influenced learning flow. However, additional research is necessary because no prior study has examined the relationship between religion and learning flow. Our post-hoc analysis showed similar results to Yu and Lee's study [10]. Therefore, enhancing course satisfaction to increase learning immersion in online classes is required. Furthermore, to increase course satisfaction, instructor-learner and learner-learner interactions should be actively promoted [20]. These goals are related to systematic curriculum, educational environment, and career direction [31]. Improving the educational environment so students can access various activities and experiences in the online environment through the development of an online curriculum is necessary to establish a customized online progress counseling system and set career direction. The correlation analysis revealed a positive correlation between self-determined learning motivation and stronger academic emotion regulation and immersion. This finding aligns with Kim and Kim's [32] study, which demonstrated a significant positive correlation between self-determined learning motivation and learning commitment. Similarly, Jeon and Yoo [2] found a significant correlation between academic emotion regulation and learning commitment among medical students in an online learning environment. A slight variation was ob-served in the participants’ major subjects, where their self-determined learning motivation, a cognitive factor, and academic emotion regulation were closely related, with immersion being optimized for the situation. This result suggests that the cognitive factor of self-determined learning motivation and the affective factor of academic emotion regulation are not independent. Consequently, academic emotion regulation necessitates that learners manage their emotions constructively according to the learning context. Moreover, the study's results corroborated that self-determined learning motivation directly influences learning flow and indirectly impacts by mediating academic emotion regulation. These findings are consistent with those in the broader literature. For example, Seo and Kim [33] found that academic emotion regulation indirectly affects learning strategies, which subsequently significantly impacts academic achievement. Similarly, Bang [34] discovered it directly influences academic emotion regulation and learning flow. This study confirmed that self-determined learning motivation and academic emotion regulation significantly impact nursing students’ learning flow. Therefore, academic emotion regulation variables, encompassing the learner's emotion awareness, goal-congruent behavior, positive reappraisal of emotions, and approach to emotion regulation strategies, are crucial parameters influencing the learning process and learning flow [10]. Therefore, educational programs to enhance self-determined learning motivation and academic emotional regulation are needed to increase nursing students’ learning engagement. These learners must combine theory and practice in an educational environment that combines non-face-to-face and virtual education. Self-de-termined learning motivation is critical for them. It can be a driving force for them to fulfill their studies and compen-sate for deficiencies independently and thus is an essential learning engagement variable. Therefore, various educational strategies for self-determined learning motivation and academic emotional regulation are necessary to improve competence through nursing students’ learning engagement. These changes will allow them to grow into future professional nurses

This study is significant because it confirmed the extent to which self-determined learning motivation, academic emotion regulation, and learning flow are present in nursing students and the mediating role of academic emotion regulation in the relationship between self-determined learning motivation and learning flow. Amidst the rapid transition to online education due to COVID-19 restrictions, academic emotion regulation, encompassing various emotional aspects, emerges as a crucial variable for enhancing learning flow and should be considered when developing appropriate educational programs.