Questions of the compatibility of Thesaurus and UDC.

In the documentation systems the effective search can be realised by the combination of UDC and Thesaurus. However, between the two classification systems there is no compatibility. A descriptor can be characteristic of several classes at the same time. One class may have several descriptors as characteristic feature.

Therefore the best user support is connecting the descriptors with the notations. The descriptors function as characteristics of the notations.

Some important problems appear.

The homonyms and the polysemes have to be treated with special attention. The same descriptor can be characteristic of several classes.

From different points of views the descriptor may have different meanings. It is not possible to assign characteristics to each class in simple forms.

Because of these two problems the traditional relation structure of the Thesaurus must be modified.

The Hungarian universal Thesaurus and the UDC is under the process of connection at present. Appropriate notations are assigned to each descriptor and non-descriptor.

Based on the accumulated experience thereby the universal characteristic of the Thesaurus is increased. The determination of new descriptors has high probability.