A survey of computational steering environments

Computational steering is a powerful concept that allows scientists to interactively control a computational process during its execution. In this paper, a survey of computational steering environments for the on-line steering of ongoing scientific and engineering simulations is presented. These environments can be used to create steerable applications for model exploration, algorithm experimentation, or performance optimization. For each environment the scope is identified, the architecture is summarized, and the concepts of the user interface is described. The environments are compared and conclusions and future research issues are given

Steering programs via time travel

Despite years of research into human computer interaction (HCI), the environments programmers must use for problem-solving today—with separate modes and tools for writing, compiling, testing, visualizing, and debugging— derive their basic structure from historical accident, and take little advantage of HCI research into the cognitive issues of programming. Neglecting these issues is an impediment to the programmers' ability to produce reliable, maintainable software. In this paper, we describe a system in which programmers can modelessly steer as they specify, visualize, explore, and alter the behavior of a program while traveling through the program's logical time. This approach supports two often-neglected cognitive principles that programmers need for problemsolving.Keywords: Visual programming, Development tools, Debugging, Steering, Psychology of programming, Programming environmentsKeywords: Visual programming, Development tools, Debugging, Steering, Psychology of programming, Programming environment

Development of an Intelligent Monitoring and Control System for a Heterogeneous Numerical Propulsion System Simulation

The NASA Numerical Propulsion System Simulation (NPSS) project is exploring the use of computer simulation to facilitate the design of new jet engines. Several key issues raised in this research are being examined in an NPSS-related research project: zooming, monitoring and control, and support for heterogeneity. The design of a simulation executive that addresses each of these issues is described. In this work, the strategy of zooming, which allows codes that model at different levels of fidelity to be integrated within a single simulation, is applied to the fan component of a turbofan propulsion system. A prototype monitoring and control system has been designed for this simulation to support experimentation with expert system techniques for active control of the simulation. An interconnection system provides a transparent means of connecting the heterogeneous systems that comprise the prototype