Computational steering
Encyclopedia
Computational steering is the practice of manually intervening with an otherwise autonomous computational process, to change its outcome. The term is commonly used within the numerical simulation community, where it more specifically refers to the practice of interactively guiding a computational experiment into some region of interest.
Some real examples of computational steering are:
, where some or all of the feedback
is provided interactively by the operator.
All computational steering mechanisms have three fundamental components:
) refers to the following practice as interactive steering.
Examples
A simple, but contrived, example of computational steering is:- In a simulated chess match with two automated players: manually forcing a certain move at a particular time for one player, to change the evolution of the game.
Some real examples of computational steering are:
- In a population dynamicsPopulation dynamicsPopulation dynamics is the branch of life sciences that studies short-term and long-term changes in the size and age composition of populations, and the biological and environmental processes influencing those changes...
simulation: changing selection pressures exerted between hosts and parasites, to examine the effect on their coevolution.
- In a fluid dynamicsFluid dynamicsIn physics, fluid dynamics is a sub-discipline of fluid mechanics that deals with fluid flow—the natural science of fluids in motion. It has several subdisciplines itself, including aerodynamics and hydrodynamics...
simulation: resetting the phase state of an immiscible fluid, to speed the search for its critical separation temperature.
System design
Computational steering systems are a manner of feedback control systemControl system
A control system is a device, or set of devices to manage, command, direct or regulate the behavior of other devices or system.There are two common classes of control systems, with many variations and combinations: logic or sequential controls, and feedback or linear controls...
, where some or all of the feedback
Feedback
Feedback describes the situation when output from an event or phenomenon in the past will influence an occurrence or occurrences of the same Feedback describes the situation when output from (or information about the result of) an event or phenomenon in the past will influence an occurrence or...
is provided interactively by the operator.
All computational steering mechanisms have three fundamental components:
- A target system that is being studied
- A representation of the target system, typically a graphical visualization, that can be perceived by the investigator
- A set of controls that the investigator can use to provide feedback that modifies the state, behavior, or product of the system being studied
Disambiguation
There appears to be a distinction that the term computational steering is used only when referring to interaction with simulated systems, not operational ones. Further clarification on this point is needed. For example: Vetter (who is apparently well acquainted with the computational steering field) refers to the following practice as interactive steering.
- In a grid computingGrid computingGrid computing is a term referring to the combination of computer resources from multiple administrative domains to reach a common goal. The grid can be thought of as a distributed system with non-interactive workloads that involve a large number of files...
framework: adjusting the cache size of a computational process, to examine the effect on its performance.