Abstract: To realize the synergistic acquisition of knowledge units in the web2.0 environment, this paper discusses the knowledge unit representation in the web2.0 environment. On the basis of this, the group argumentation task is established by taking the attributes of a knowledge unit as its main body. By use of the consensus state model of group argumentation, the fusion of different knowledge unit versions derived from the knowledge unit is achieved, and then the synergistic acquisition of knowledge units is realized. The results show that taking knowledge units as the structured representation of knowledge is helpful to knowledge sharing, diffusion and problem solving support in the web2.0 environment; the quantitative and operable synergistic acquisition of knowledge units method proposed based on the group argumentation theory is beneficial to computer-aided synergistic knowledge acquisition in the web2.0 environment; applying the group argumentation theory in synergistic acquisition of knowledge units in the web2.0 environment contributes to group members expressing their views more conveniently and independently compared with the traditional group argumentation, which makes the acquired knowledge be more objective and comprehensive, and thus extends the application of the group argumentation theory to a certain extent.

Key words: knowledge unit, synergistic acquisition, Web2.0, group argumentation