A scientific multimedia database system for polymer science experiments

This paper describes SciMMDB, a scientific multimedia database system designed for polymer science experiment data applications. SciMMDB maintains multimedia data types of video, test and picture (as well as other standard data types), and allows users to: form multimedia presentation streams about experiments; define a presentation which organizes a number of presentation streams for playout purposes; and control the playout of a presentation. To form video, text or picture streams, a presentation stream construction language is described. Queries in this language express spatial and temporal relationships involving content objects and efficient evaluation of such queries are facilitated by indexing structures. SciMMDB uses IB+trees for queries involving temporal intervals. In SciMMDB, presentation streams are formed into a presentation using the notion of presentation graphs. During the playout of a presentation, each presentation stream in the presentation is played out by a separate transaction, called an output agent. Such transactions communicate and synchronize with each other using the cooperative transaction model