The nanofriction properties of hexagonal boron nitride (h-BN) are vital for its application as a substrate for graphene devices and solid lubricants in micro- and nano-electromechanical devices. In this work, the nanofriction characteristics of h-BN on Si/SiO2 substrates with a bias voltage are explored using a conductive atomic force microscopy (AFM) tip sliding on the h-BN surface under different substrate bias voltages. The results show that the nanofriction on h-BN increases with an increase in the applied bias difference (Vt−s) between the conductive tip and the substrate. The nanofriction under negative Vt−s is larger than that under positive Vt−s. The variation in nanofriction is relevant to the electrostatic interaction caused by the charging effect. The electrostatic force between opposite charges localized on the conductive tip and at the SiO2/Si interface increases with an increase in Vt−s. Owing to the characteristics of p-type silicon, a positive Vt−s will first cause depletion of majority carriers, which results in a difference of nanofriction under positive and negative Vt−s. Our findings provide an approach for manipulating the nanofriction of 2D insulating material surfaces through an applied electric field, and are helpful for designing a substrate for graphene devices.

Apply digital coding technology and badminton men’s technical and tactical statistical analysis system to analyze men’s doubles competition data, provide statistical results of the position and line of the hitting technique, perform relevant analysis of technical and tactical applications between the opponent and the opponent, and analyze historical events. In addition, the use of computer coding technology to analyze the data, for the athletes to formulate the battle plan before the game, provide effective basis for timely and targeted adjustment of technical and tactics, and make a comprehensive summary after the game.

With the change of people’s parenting concept, Chinese residents tend to let children sit in daily life, which will lead to the continuous decline of children’s physical health. Therefore, the detection rate of obesity and overweight of children in China continues to rise, which requires kindergartens to choose a more efficient physical exercise method. Through scientific physical health education, we can guide children to pay attention to physical exercise, which will help them acquire lifelong sports awareness and ability. At the same time, physical health education can promote children’s health, which is also the most effective measure. Therefore, some kindergartens have formed children’s physical education curriculum with the help of modern information technology, which will help children better develop their physical quality. However, some kindergartens also have some problems when introducing physical fitness courses, such as lack of experience, lack of understanding of concepts, curriculum confusion, etc., which will be difficult to fully reflect the development of physical fitness. First of all, this paper analyzes the impact of physical training on children. Then, this paper analyzes the problems of modern information technology. Finally, some suggestions are put forward.

The ubiquitous rhythm in competitive sports activities not only affects athletes’ competitive style and performance, but also determines their performance to a certain extent. The research on the basic theory and empirical application of competition rhythm will help improve the athletes’ cognitive level of competition activities. The analysis and elaboration of the basic theoretical problems of badminton competition rhythm based on computer association rules mining can solve many practical problems such as the application and control of badminton competition rhythm in sports training and competition, and establish badminton competition rhythm theory. In addition, it also has important research significance and value for the practical application of badminton.

From 1982 to 2018, the Wed of Science core collection database included 2999 pieces of literature information on children’s physical activity research, and data cleaning and visualization analysis was carried out by Citespace V software. The purpose is to study the international research in this field in China. The integration of the rail provides information support. The study found that: At present, the main force of foreign children’s physical activity research is concentrated in the developed countries such as the United States, Britain, Canada, Australia; research focuses on “overweight and obesity, exercise behavior intervention, meditation behavior, nutrition and so on”. The research evolution has gone through three stages: “exploring the foundation, expanding the extension, and comprehensively sublimating”; “in the ecosystem theory” The construction and evaluation of the nested structure model of children’s physical activity is the frontier of research. The study believes that the frontier of children’s physical activity research is “construction and evaluation of the nested structure model of children's physical activity in ecosystem theory.”