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To analyze the influence of the distance between tunnels at the bridge-tunnel junction in the mountainous area on the driving safety under crosswind, a vehicle dynamics model is established by Carsim software. Under the conditions of different driving speeds (60km/h, 80km/h and 100km/h), different wind scales (level 6-9) and three alignment combinations of the tunnels (tunnel-straight road-tunnel, tunnel-curving road-tunnel, tunnel-the combination of straight and curves road-tunnel), the vehicle's lateral offset and lateral force coefficient are used as evaluation indexes to study the influence of distance between tunnels on driving safety. When the distance is small, the lateral offset and lateral force coefficient of vehicle driving on the bridge-tunnel junction increase firstly and then decrease as the distance increases. But the changes of the lateral offset and lateral force coefficient are not synchronized, and the peak value of the lateral force coefficient occurs earlier than the lateral offset. Finally, the minimum safety spacing of each condition and speed limits for different distances are proposed. Under the condition of the straight-tunnel, 20m distance between tunnels cannot ensure the driving safety when the wind scale reaches level 9, and the road should be closed. Under the conditions of the curve and the combination of straights and curves, driving safety cannot be maintained at each spacing at wind scale level 8 and 9, and the road should be closed. However, when the wind speed is level 6 or 7, speed limits can be adopted to ensure driving safety. The results suggest that vehicles' lateral offset and lateral force coefficient can be effectively reduced by reducing the driving speed or increasing the distance between tunnels, so the risk of accidents caused by the crosswind can be reduced.

Low temperature high-speed motors can achieve low temperature and high viscosity fluid media efficient transmission, meanwhile, excessive friction loss and temperature rise issues are addressed. In this paper, a 30kw low-temperature and high-speed permanent magnet motor prototype is implemented as the research object. Three stator axial cooling structures are proposed to effectively control the motor temperature rise. First, the discussion focuses on the friction loss in the air gap and its related influencing factors; at the same time, the effect of different axial cooling structures on the friction loss in the air gap is also considered. Secondly, a calculation method of axial viscous friction loss based on the principle of fluid force equilibrium is proposed in the paper, the variation law of the structure size influence on axial friction loss is also given. Based on the quantitative calculation of axial friction loss, the final structure size is determined by synthesizing the variation of different size structures stator iron loss. Finally, the physical model of the three-dimensional fluid-thermal coupling calculation on the analysis object is established by means of finite element analysis, and the stator temperature rise distribution is calculated.

Color harmony is the hotspot of many researchers in the fields of art and design which is widely used in various artworks and design activities. As for psychology, color harmony is closely related to human’s perception and cognition, although, the research of its generation process has not been fully focused on. With experimental psychology with artificial intelligence technology combined together, our aim is to investigate the factors affecting color harmony on the basis of the generation process from perception to cognition, and construct a mathematical model to predict its degree, so as to realize the quantitatively analysis and measurement of color harmony. We classify the factors affecting color harmony into objective and subjective ones. Among them, the objective factors are constructed based on the three principle elements of color with a total of 21-dimensional color-pair objective physical features extracted. And the subjective factors are divided into direct psychological effects and indirect psychological effects. 180 two-color combinations were evaluated by 30 subjects based on color harmony and its subjective factors on discrete scales ranging from −2 to 2. Correlation analysis reveals that color harmony is not only affected by objective factors, but also by subjective factors which has a stronger correlation than that of the objective ones. Finally, machine learning algorithms were adopted to construct a mathematical model, which has been proved that the linear relationship can well explain the generation mechanism of color harmony.