Taskmaster: an interactive, graphical environment for task specification, execution and monitoring

This thesis presents Taskmaster, an interactive, graphical environment for task specification, execution and monitoring. Taskmaster is an integrated user environment that employs a unique blend of the principles of Visual Programming, Tool Composition, Structured Analysis and Data Flow Computing to support user task specifications. Problem solving in the Taskmaster environment consists of decomposing the problem task into a partially ordered set of high-level subtasks. This decomposition is depicted graphically as a network in which the nodes correspond to the subtasks and the arcs represent the directed data paths between the nodes. The subtasks are successively decomposed into lower level subtasks until, at the lowest level, each network node is “bound” to a pre-existing tool from a tools database. Execution of the resulting network of software tools provides a task solution. Some of the novel features of the Taskmaster environment include 1) guidance to the user in the task specification process through menu-based interaction; 2) facility to interactively monitor the task network execution; 3) support for structured data flow among tools; and 4) enhanced support for reusability by providing operations to functionally abstract and reuse sub-networks of tools.