Visual Verbs: Showing Change, Movement, Force and Action in Procedural Graphics
http://www.stc.org/ConfProceed/2005/PDFs/0070.pdf

Sharp, Michael V. and Robert Krull
STC Proceedings
2005

Abstract:

Procedural graphics can use several techniques to show changes over time. Arrows, before-and-after views, ghosting of objects and other static techniques can operate as visual verbs that imply dynamic processes. We suggest several means for reducing users' ambiguity in interpreting visual verbs.