As with any computer system, the performance of supercomputers depends upon the workloads that serve as their input. Unfortunately, however, there are many important aspects of the supercomputer workloads that have not been modeled, or that have being modeled only incipiently. This paper attacks this problem by considering requested time (and its relation with execution time) and the possibilit...

A new comprehensive reflectance model is presented. The model accounts for both surface and subsurface local light scattering. The model combines, for the first time, highly-efficient wave optics components and rigorous empirical components. The model displays a wide range of directional and non-directional light scattering phenomena and compares favorably against extensive, detailed reflectanc...

We propose a conceptual model of groupware functionality. It distinguishes four basic functions a groupware application can provide to its users: support for conferences, for cooperation, for conversation and for coordination. We identify the main parameters of these basic functions. We demonstrate the application of the model by describing various categories of groupware applications in terms ...