Pattern-Based Tool Design for Shared Knowledge Construction - Collaborative Technologies and Applications for Interactive Information Design - page 26

exPerienCes interact with developers in different iteration

types. OSDP proposes three different types of
iterations: Patterns are independent from programming

languages. They help educating developers
by providing well-known design insights and
thereby foster design reuse. Links between the
patterns point to other relevant issues and thereby
support a piecemeal growth of the application
under development. Finally, they improve the
communication between clients, end-users, and
developers, when used in a iterative development
process like OSDP.
In this section, we show how patterns for
computer-mediated interaction help to design
tools for shared knowledge construction. For this
purpose, we introduce a web-based collaborative
environment and some its extensions that foster
shared knowledge construction. When describing
the design of these tools we highlight and provide
thumbnails of the patterns 1 that were used to
implement the tools.

1. In conceptual iterations users envision the

scenarios of system usage.

2. In development iterations users and de-

velopers collaborate to build the required
groupware infrastructure.

3. In tailoring iterations users appropriate the

groupware system to changed needs.

In conceptual iterations, the end-users out-
line future scenarios of use. This is informed by
the use of high-level patterns that describe how
group interaction can be supported with tools for
computer-mediated interaction.
The scenarios are implemented during devel-
opment iterations. Here, the software developers
are the main actors. They translate the scenarios
to working solutions using low-level patterns as a
development guideline. End-users closely interact
with the developers by proposing the application of
patterns from the pattern language and identifying
conflicting forces in the current prototype.
As soon as the tool for computer-mediated
interaction can be used by the end-users, the
tailoring iterations start. End-users reflect on the
offered tool support. Whenever the support can
be improved, they either tailor the tool by using
high-level patterns or escalating the problem to
the developers who then start a new development
iteration.
As OSDP is an iterative approach, each iteration
may actually be performed multiple times: in fact,
developers and end-users may even choose to go
back to a previous iteration type. In all iteration
types, the patterns primarily communicate design
knowledge to the developers and the users. The
participants of the OSDP learn how conflicting
forces should be resolved instead of just using
pre-fabricated building-blocks. This empowers
them to create customized solutions that better
suit their requirements.

Cure in a nutshell

In this section, we introduce the web-based col-
laborative system CURE (J. M. Haake, Schümmer,
Haake, Bourimi, & Landgraf, 2004). CURE is
used for collaborative work and learning. Typical
collaborative learning scenarios are collaborative
exercises, tutor-guided groups with collaborative
exercises, collaborative exam preparation (Lu-
kosch & Schümmer, 2006b), virtual seminars,
and virtual labs (Schümmer, Lukosch, & Haake,
2005). When considering collaborative work
typical use cases include group formation, group
communication, document sharing, collaborative
writing, collaborative task management etc. All
these scenarios have in common that users interact
to create shared knowledge.
Users can structure their interaction in groups
that inhabit virtual R o o m s . Room metaphors
(Greenberg & Roseman, 2003; Pfister, Schuck-
mann, Beck-Wilson, & Wessner, 1998) have been
widely used to structure collaboration. Figure 2