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R S Kalawsky

Publications and source records attributed to R S Kalawsky.

3 recordsLinked to original sources

Improving scientists' interaction with complex computational-visualization environments based on a distributed grid infrastructure.

The grid has the potential to transform collaborative scientific investigations through the use of closely coupled computational and visualization resources, which may be geographically distributed, in order to harness greater power than is available at a single site. Scientific applications to benefit from the grid include visualization, computational science, environmental modelling and medical imaging. Unfortunately, the diversity, scale and location of the required resources can present a dilemma for the scientific worker because of the complexity of the underlying technology. As the scale of the scientific problem under investigation increases so does the nature of the scientist's interaction with the supporting infrastructure. The increased distribution of people and resources within a grid-based environment can make resource sharing and collaborative interaction a critical factor to their success. Unless the technological barriers affecting user accessibility are reduced, there is a danger that the only scientists to benefit will be those with reasonably high levels of computer literacy. This paper examines a number of important human factors of user interaction with the grid and expresses this in the context of the science undertaken by RealityGrid, a project funded by the UK e-Science programme. Critical user interaction issues will also be highlighted by comparing grid computational steering with supervisory control systems for local and remote access to the scientific environment. Finally, implications for future grid developers will be discussed with a particular emphasis on how to improve the scientists' access to what will be an increasingly important resource.

Computer Graphics↗

A grid-enabled lightweight computational steering client: a .NET PDA implementation.

The grid has been developed to support large-scale computer simulations in a diverse range of scientific and engineering fields. Consequently, the increasing availability of powerful distributed computing resources is changing how scientists undertake large-scale modelling/simulation. Instead of being limited to local computing resources, scientists are now able to make use of supercomputing facilities around the world. These grid resources comprise specialized distributed three-dimensional visualization environments through to massive computational systems. The scientist usually accesses these resources from reasonably high-end desktop computers. Even though most modern desktop computers are provided with reasonably powerful three-dimensional graphical hardware, not all scientific applications require high-end three-dimensional visualization because the data of interest is essentially numerical or two-dimensional graphical data. For these applications, a much simpler two-dimensional graphical displays can be used. Since large jobs can take many hours to complete the scientist needs access to a technology that will allow them to still monitor and control their job while away from their desks. This paper describes an effective method of monitoring and controlling a set of chained computer simulations by means of a lightweight steering client based on a small personal digital assistant (PDA). The concept of using a PDA to steer a series of computational jobs across a supercomputing resource may seem strange at first but when scientists realize they can use these devices to connect to their computation wherever there is a wireless network (or cellular phone network) the concept becomes very compelling. Apart from providing a much needed easy-to-use interface, the PDA-based steering client has the benefit of freeing the scientist from the desktop. It is during this monitoring stage that the hand-held PDA client is of particular value as it gives the application scientist greater freedom to leave his or her desk but still communicate with their simulation, with the proviso that they remain within the range of a wireless network.

Computer Graphics↗

VRUSE--a computerised diagnostic tool: for usability evaluation of virtual/synthetic environment systems.

A special questionnaire (VRUSE) has been designed to measure the usability of a VR system according to the attitude and perception of its users. Important aspects of VR systems were carefully derived to produce key usability factors for the questionnaire. Unlike questionnaires designed for generic interfaces VRUSE is specifically designed to cater for evaluating virtual environments, being a diagnostic tool providing a wealth of information about a user's viewpoint of the interface. VRUSE can be used to great effect with other evaluation techniques to pinpoint problematical areas of a VR interface. Other applications include bench-marking of competitor VR systems.

Consumer Behavior↗