With the rapid development of the global economy, transport safety and security have become the key issues in maritime transportation all over the world. In practical applications, the Automatic Identification System (AIS)-based measurement of similarities between different vessel trajectories plays an important role in improving maritime transportation, e.g., maritime navigation, maritime supervision and management. However, the received AIS datasets are usually composed of a large amount of redundant information which could significantly increase the computational complexity. To deal with this problem, a Douglas-Peucker (DP)-based calculation method is introduced in this paper to accurately compress the spatio-temporal AIS trajectories while preserving the main geometrical structures. Based on the compressed trajectories, it is able to accelerate the Dynamic Time Warping (DTW) algorithm for the measurement of similarities between different vessel trajectories. In particular, the combination of DP and DTW has the capacity of significantly reducing the computational cost and guaranteeing the accuracy of similarity measures. The experimental results have demonstrated the superior performance of the proposed method in terms of computational cost and accuracy of similarity measures.

Luxun, whose works are well-received in Japan, is regarded as a ‘national author’. In 1909, Japanese print media for the first time reported such a ‘thought warrior’ and ‘literature master’. Since then, scholars studying Luxun has made their effort to advertise Luxun. Even up to now, it is fair enough to say as an ‘advocate’ of Chinese national culture, Luxun is still boasting of his radiance, because his works are as mellow as wine, leading readers to meaningful afterthoughts. It is found both in China and Japan that language textbooks of primary and secondary school are seen as a medium to learn about Luxun. Interpreting and teaching Luxun’s works can not only render people more capable of using language, but spread literature knowledge and enrich spiritual wold. Separated by the East China Sea, Japan published the first translated work written by Luxun in 1920s and his articles in Japanese language textbooks were also translated by famous indigenous writers or translators. There are two benefits when we take a look at how many articles written by Luxun are collected into Japanese language textbooks, explore the collecting background, interpret textbooks and analyze exercises about his articles. One is that we can have a clear understanding of the popularity and acceptance of ‘Luxun Spirit’ in Japanese basic education. The other is that we can draw some important lessons for our teaching about Luxun in middle school, and the teaching and study of ‘ China-Japan comparative literature’ for Japanese major students.