**3. Knowledge crystallisation**

190 New Research on Knowledge Management Technology

In this phase, descriptions (documents about some topic) may be added to the system both by the members of the steering committee and by other users that are considered as collaborators. However, only the members of the steering committee have the complete capability of voting on the documents, and thus in deciding which documents crystallise. Collaborators may have limited capability of voting, if the steering committee

*It is created a new knowledge area.* 

tree of the knowledge area.

*based on "virtual communities".* 

community members again.

*contributions arrive.*

Eventually, the steering committee may decide to advance the area of knowledge to the "active" mode, possibly when a critical mass of participants and interactions is achieved. In this moment there should be a single tree structure for the area, decided by consensus. Then the steering committee is dissolved and the subsequent crystallisation of the knowledge is

During the "active" phase, when one user contribution crystallises, s/he receives a certain amount of "votes" that s/he may apply for the crystallisation of other documents (of other authors) in the virtual community where her/his crystallised document is located. As in the previous phase the descriptions may be added both by experts and collaborators; in fact all users start using the system as collaborators and when a document of a user crystallises s/he becomes an expert in related communities of the topic where the

The other aspect of knowledge crystallisation is the evolution of the structure of the knowledge tree. If a member of a virtual community proposes to add a new subject to a topic, remove a subject from a topic or move a subject from one topic to another topic, then a minimum quorum of positive votes from other members of the community will be

*There is a "steering committee" in charge of many of the decisions that is distributed in later phases. For example, they* 

The community may decide to return to supervised stage to engage in a process of re-structuration the knowledge

*There is a lot of activity about the contents of the knowledge area, that is, new knowledge in form of fragments or descriptions of topics is arrived. Knowledge Crystallisation is* 

Contributions rate increases. There are many active

*There are few changes. Most of activity is consultation and few* 

*will decide on the way knowledge is structured.* 

decides so.

*NEW KNOWLEDGE AREA* 

*SUPERVISED PHASE*  The steering committee may decide to promote the knowledge area to the Active stage, when the knowledge tree of the knowledge area is created.

*ACTIVE PHASE* 

*STABLE PHASE* 

active.

After some time, many of the members of the original community cease to be

based on virtual communities.

necessary for the change to be made.

document is located.

Fig. 3. Knowledge evolution of a knowledge area

A central concept in this work is the "Knowledge Crystallisation" mechanism. With this mechanism it could be possible to have, in each moment, the best knowledge elements in a knowledge area, in opinion of the user community.

The mentioned KnowCat knowledge elements –documents, notes, version documents, topics– are produced by the users and their lifetime depends on the patterns of their usage. Any of these elements will stay longer in the knowledge area if it is frequently used and receive favourable opinions from other users. In that case, its crystallisation degree will rise, and thus its probability to stay in the knowledge area. However, if one knowledge element is not used or it doesn't receive favourable opinions by the users, then it will eventually disappear from the knowledge area as a consequence of its crystallisation degree going down. This mechanism is called Knowledge Crystallisation.

Firstly, it is shown in the next section the crystallisation of documents. Secondly, it is shown the crystallisation of annotations, and version documents. Finally, it is shown the crystallisation of the structure.
