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In the wheel hub industry, the quality control of the product surface determines the subsequent processing, which can be realized through the hub defect image recognition based on deep learning. Although the existing methods based on deep learning have reached the level of human beings, they rely on large-scale training sets, however, these models are completely unable to cope with the situation without samples. Therefore, in this paper, a generalized zero-shot learning framework for hub defect image recognition was built. First, a reverse mapping strategy was adopted to reduce the hubness problem, then a domain adaptation measure was employed to alleviate the projection domain shift problem, and finally, a scaling calibration strategy was used to avoid the recognition preference of seen defects. The proposed model was validated using two data sets, VOC2007 and the self-built hub defect data set, and the results showed that the method performed better than the current popular methods.

Based on the analysis of the language policy patterns of the U.S.A., the article combs on its history of Chinese teaching. It’s proposed that the 130 years of history can be divided into four periods according to different policy patterns. These are nonintervention policy before the Second World War, priority policy during the war, containment- priority- diversity policies after the war, and priority policy in the 21st century. Based on these analyses, a revised policy pattern mode is provided for analyzing foreign language policy.

In order to accurately explore the droplets distribution characteristics on the ground and space during the aerial spray process, a single-pass application test based on the determination of effective swath by a Bell206L4 helicopter was carried out. The accurate effective swath width of the helicopter spray operation was obtained, and the cumulative and spatial drift characteristics of droplet deposition when the helicopter used different aerial nozzles under natural environment were systematically analyzed. The results showed that the average effective swath width of three different types of nozzle were 25.3 m (CP02), 29.7 m (CP03) and 29.3 m (CP04) with an average flight altitude of 11 m and velocity of 17 m/s. The average deposition volume in the effective swath area of each sampling line was in the range of 1.208-2.735 ?L/cm 2 . Most of the droplets in each application were concentrated near the route and the adjacent locations of the effective swath area. In addition, the droplets with small size were trend to drift, and the increased nozzle orifice size was beneficial to reduce drift. In terms of spatial drift distribution, small-sized droplets usually gathered in the upper space, larger-sized droplets were easy to gather in the middle space, and the medium-sized droplets were trend to gather in the lower space. The research results were helpful to optimize the spray plan and provide reference for precision aerial application. Keywords: aerial spray, droplet deposition, spatial drift, effective swath, helicopter, precision agricultural DOI: 10.33440/j.ijpaa.20210401.145 Citation: Yao W X, Guo S, Yu F H, Du W, Meng Y H, Wang J, Chen P C, et al. Droplet deposition and spatial drift distribution characteristics of aerial spraying based on the determination of effective swath. Int J Precis Agric Aviat, 2021; 4(1): 36–43.

At present, China is attaching importance to the issue of labor education for students, upgrading the traditional "four education" to "five education", that is, adding labor education on the basis of morality, intelligence, physical education and beauty. The relevant colleges and universities in China are exploring how to carry out the teaching of vocational labor education. As a relevant university in the labor field, the school where the author works is also actively exploring various issues concerning professional labor education, including exploring the curriculum setting of professional labor education, the proportion of class hours of relevant courses, the content of relevant courses, and how to carry out professional intercommunication teaching with relevant majors. This paper systematically divides the professional labor education curriculums obtained from the conference and discussion held by the relevant professors in the author's school, it means that the professional labor education curriculums are graded. Then by adopting the combination of qualitative and quantitative analytic hierarchy process (AHP) combined with multiple expert assessment of classifying labor education curriculum evaluation and determine the weight of each course in the professional labor education courses. So as to determine the importance of professional labor education courses for professional labor education teaching, to provide theoretical support for the development of professional labor education courses in the country. At the same time, it also provides technical support for introducing professional labor education into safety engineering teaching. Through the research of this paper, it is found that the application course of professional labor education is the most important part of professional labor education curriculum, and the setting of such courses should be strengthened. Simultaneously, the thoughts of labor and thought, labor and law, labor and safety, labor and economy in professional labor education courses can be introduced into the teaching of safety engineering courses.