Online educational systems running on smart devices have the advantage of allowing users to learn online regardless of the location of the users. In particular, data synchronization enables users to cooperate on contents in real time anywhere by sharing their files via cloud storage. However, users cannot collaborate by simultaneously modifying files that are shared with each other. In this paper, we propose a content collaboration method and a history management technique that are based on distributed system structure and can synchronize data shared in the cloud for multiple users and multiple devices.

翻译：使用智能设备运行的在线教育系统的优势在于允许用户在线学习,而不论用户的所在地。 特别是,数据同步使用户能够通过云存储共享文件,在任何地方实时合作处理内容。 然而,用户无法同时修改彼此共享的文件,同时修改彼此共享的文件。 在本文中,我们提出了一个内容协作方法和历史管理技术,该方法基于分布式系统结构,可以同步多个用户和多个设备共享的云中数据。