37.2 DAGS 92 Sample Guided Tour

In a typical session, users can first get a quick overview of the contents of the CD-ROM. Then they can follow a talk on a particular topic that seems interesting by watching the movies of the transparencies and of the speaker. They can also get an overview of the talk by using the pop-up menu containing the section titles of the talk (by pressing the button "Jump to Highlights"), or by skimming through the transparencies. If, at some particular point, the speaker mentions a theorem without proof, as is usually the case in conferences, users can jump into the hypertext to read the omitted proof in detail. Then, they can go back to the talk or continue reading the hypertext bringing on the screen several windows containing relevant information. They can also do a search on some keyword to find out who else mentioned this keyword during the conference. Assuming that the search brought up several candidate sections of papers, users can jump into another paper and continue reading from there, or even jump into the video movie of the second speaker and see how the material was presented during that talk. That way they can, for example, compare opinions on the speaker's view on a particular topic, or simply see different presentation techniques on the same subject.

We will now describe a possible tour through the hypermedia document to give the reader an impression of the features of our system.

Figure IV.3 Table of contents screen

The system starts up with a title animation, and then presents a table of contents (figure IV.3) that gives users direct access to the eight invited talks. In this example the user decides to study the talk by Charles Leiserson about "The Network Architecture of the Connection Machine CM-5." The user clicks on the title of this talk on the contents screen and the system jumps to the speaker screen.

Figure IV.4 Speaker screen

On the speaker screen (figure IV.4) users can get background information about a particular talk by reading a short biography of the speaker, obtain a list of the talk's highlights, read the hypertext version of the paper related to the talk, or actually watch the talk. Another button can take them back to the previous "Table of Contents" screen. The user here decides to view the talk and clicks on the "View Talk" button.

Figure IV.5 Talk screen

The system now switches to the talk screen (figure IV.5) where users can watch the actual talk from the beginning by clicking the "Start Talk" button, or go back to the "Speaker" and "Contents" screen by clicking the appropriate buttons. They can also jump to any position within the talk using the slider controls on the left panel underneath the transparencies.

Figure IV.6 Highlights of the talk

Another useful feature is the option to jump directly to the beginning of a subsection within the talk using the "Jump to Highlight" button. Upon pressing that button, the user is presented with an ordered pop-up-list of the highlights of the talk (figure IV.6). In this example the user chooses to watch Charles Leiserson explain the "CM-5 Data Network."

Figure IV.7 Charles Leiserson talks about the CM-5 Data Network

When the user releases the mouse button, the system jumps directly to the "CM-5 Data Network" section within Charles Leiserson's talk (figure IV.7). After following the talk for a while, users might want to read the paper associated with the talk. They can do that by clicking at the "Gloor/Dynes Hypertext" button.

Figure IV.8 The hypertext version of the paper.

The system now jumps directly to the beginning of the paper associated with the talk. On the left of the article screen (figure IV.8) is a palette of tools that provide (from top to bottom)
Help
A map of the hypertext contents,
A table of contents
Bookmark facilities
A notebook
Marginal Notes
Below is the "navigation diamond" that marks the hypertext node level and its connections to other node levels.

On the right side is another palette with buttons that provide (from top to bottom)

A list of topics related to the current text node,
The ability to add hyperlinks between text nodes,
A history of the nodes visited by the user in this session
The ability to create a path through the nodes
(or to use a predefined one that takes them through the proceedings in a linear fashion)
A link to the Talk Screen
A button to the figures related to the current node (de-highlighted when there is none).
The button at the bottom returns the user to the node previously visited.

Figure IV.9 Figures, bibliographies and footnotes appear in separate windows

Following the level 2 nodes by clicking on the right arrow of the navigation diamond, the user brings up the next introductory node of the paper. A bibliographical reference or a figure mentioned in the paper can be opened by clicking on the word (figure IV.9). To get a feeling of the structure of this paper, the user can also bring up the overview map by clicking the "map" button.

Figure IV.10 Hypertext map

The system brings up the overview map that shows a graphical structure of the whole hypertext document in relation to the actual viewpoint of the user (figure IV.10). Users learn that they are on the section entitled "The CM-5 Data Network" of the "The Network Architecture of..." paper. Information about previous and next sections also appears, along with information about the subsections of the current section. Clicking on another box makes this box the new center of the map, by "option-clicking" a box, the user can jump to any node in the hypertext.

There are numerous other features in the system that can not be shown in this brief guided tour. The reader is referred to the user's manual of the Parallel Computation CD-ROM [Glo93b] for a more detailed description of the user interface.