Cache and prefetch mechanisms for improving symbol usage in symbol based applications

Symbol based applications are aimed for alternative and augmentative communication and education of persons with complex communication needs. Since available symbol galleries typically contain huge number of symbols that are graphical representations of words, and since one of the favorable user requirements is that application supports multiple symbol galleries, a problem of presenting a subset of the most commonly used symbols on graphical interface occurs along with the dilemma where to place galleries - locally on the device or on server side, which then requires Internet connection. Paper discusses three known mechanisms for predicting the content that user needs based on single user behaviour, multiple user behavior, content structure and their combination that could be applied in symbol based applications. Implementation of cache and prefetch mechanisms is presented for case study of symbol usage in primary school English learning materials.