Two years before the mist: experiences with Aquanet

Abstract

Aquanet is a collaborative hypertext tool that combines elements of frame-based knowledge representation and graphical presentation. In this paper, we examine the first major application of the tool in an analysis task, a two year long technology assessment that Rsulted in ahnost 2000 nodes and more than 20 representational types. First, we cover the implications of the representational resourees provided and representational deeisions that were made. Then we discuss how spatial layout was used in lieu of the complex relations Aquanet’s data model supports. Finally, we show how distinct regions emerged to refleet particular activities and how they were subsequently used as the basis for a later collaboration on a Similar task. 1 Overview: The tool and the task Aquanet is a collaborative hypertext tool designed to meet the needs of knowledge structuring tasks like analysis and argumentation. The tool combines elements of frame-based knowledge representation and graphical presentatio~ it has its roots in gIBIS [4], Germ [3], NoteCards [5], and IDE [15]. This paper examines how Aquanet was used in a large application, a multi-year assessment of a specific area of researeh and technology development. This type of analysis is common in business intelligence and other kinds of information-intensive interpretive processes. Permission to copy without fee all or part of this material is granted provided that copies are not made or distributed for direct commercial advantage, the ACM copyright notice and the title of the publication and its date appear, and notice is givem that copying is by permission of the Association for Computing Machinery. To copy otherwise, or to repubtish, requires a fee and/or specific permission. @1992 ACM 0-89791-547-X/92/OOll/O053/ $1.50 1.1 Hypertext to keep your knowledge in place Aquanet enables people to describe a domain of discourse in terms of basic objects and how they are interrelated (relations). For example, in an evaluation of a computer technology, one type of basic objeet might be a “system,” and another type might be a “developer.” These two elements might be connected by an “implemented” relation. Instances of these types can then be manipulated in a shared information space. The structures that may be built within any particular information space are specified by a schema, a collection of Aquanet basic object and relation types. [10] presents a more extensive description of the tool and its data model. Figure 1 shows a limited view of a much larger Aquanet information space. A user can zoom or scroll this view to see more of the space, which can extend in all directions. Objects shown in the primary view are drawn according to a user-specified graphic appearance that is associated with each type of basic object and relation. For example, the seleetion an instance of a System object is portrayed on the computer screen as purple rectangle that displays the object’s name, which in this ease is “Atlas.” As is apparent in the figure, objects may overlap, users can manipulate the stacking order to see obscured objects. In Figure 1, the view onto the information space is partially obscured by a separate scrollable window that shows the selected System’s internal structure, its slots. In this ease, the slots “Name,” “Commercial?: “Language-pairs,” and “Performance Data” and their values are visible in the smaller window. Like many other spatially-oriented systems, the Aquanet information space can contain multiple references to the same object. We call these references virtual copies. All of the copies share the same graphic appearance, and when one is selected, all visible copies are highlighted. This mechanism becomes important in our later discussion of informal relations. 54 ACM ECHT CONFERENCE Figure 1. A portion of an Aquanet main view with a separate window onto the contents of a node.