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In the vibration cast‐rolling process, the metal material is in the state of sub‐rapid solidification. Based on the principle of solidification and random theory, the relation between the vibrating process with sub‐rapid solidification and the number of new crystal nuclei was deduced. The theoretical analysis, numerical simulations and experiments of sub‐rapid solidification under vibration were performed. The results show that the modified Cellular Automaton‐Finite Element model can predict the solidified microstructure and size of crystal grains. The results also show that vibration with chilling can effectively promote the production of free crystal nuclei. With a higher frequency of vibration, the area of the equiaxed zone can increase, and the grains can be smaller.

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Immersive virtual reality technology (IVR) can create contextualized learning environments that learners cannot easily access. It is widely used in education. More and more researchers are paying attention to IVR's influencing factors. However, most of these researches focus on the aspects of technology and environment, ignoring the aspects of learners themselves. Therefore, this paper explores the impact of learners' attention level (AL) and learning style (LS) on learning behavior in IVR. Firstly, the AL data monitored by EEG equipment allows correlation and difference analysis to explore the relationship among AL, LS and learning performance (LP). Then, according to the video-recorded learning behavior data, the lag sequence analysis method is used to analyze the learning behavior sequence transformation of the high-concentration group and low-concentration group so that it can explore the problem learning behaviors of learners with different concentrations. The results show that: in the virtual learning environment (Vir-LE), there is a strong positive correlation between AL and LP. There is no significant difference in LP with different LS, but the AL of visual learners is higher than that of verbal learners. Through this experiment, it is helpful to eliminate the interference factors in the range of human subjective perception and improve the accuracy of the measurement of learning effect.

Immersive virtual reality technology has been widely used in teaching and learning scenarios because of its unique visual and interactive experiences that bring learners a sense of immersive reality. However, how to better apply immersive virtual reality technology to learning environments to promote learning effectiveness is a direction that has been studied and explored by many scholars. Although a growing number of studies have concluded that immersive virtual reality technology can enhance learners’ attention in teaching and learning, few studies have directly linked both learning behaviors and attention to investigate the differences in behavioral performance across attention. In this study, attention data monitored by EEG physiological brainwaves and a large number of videos recorded during learning were used to explore the differences in the sequence of high attention behaviors across performance levels in an immersive virtual reality environment using behavioral data mining techniques. The results found that there was a strong correlation between attention and performance in immersive virtual reality, that thinking and looking may be more conducive to learners’ concentration, and that high concentration behaviors in the high-performing group accompanied the test and appeared after the monitoring, while the action continued to be repeated after the high concentration behaviors in the low-performing group. Based on this, this study provides a reference method for the analysis of the learning process in this environment, and provides a theoretical basis and practical guidance for the improvement of participants’ attention and learning effectiveness.