1. INTRODUCTION
It is the goal of system designers goal to create useful and usable
solutions for customer problems based on appropriate technology.
As a first step towards this goal, designers learn about a problem
domain from appropriate domain experts while bringing to bear
their knowledge of technology [1]. To develop an understanding
of the requirements for a system, they can use any of the large
number of approaches and methods researchers and practitioners
in the fields of human-computer interaction (HCI) and software
engineering have developed, including user-centered design [7],
scenario analysis [2], and contextual inquiry [1]. Other methods
are available for supporting the subsequent work of evolving a
conceptual design into a prototype. These include rapid
prototyping, iterative design [4] and questions, options and
constraints (QOC) [7].