[en] Following scope of tasks are performed to establish the nuclear data base which is the infra structure for the nuclear related research and industry. - Upgrade of Table of Nuclides web service and addition of new feature to existing ENDF plotting services. - Establishment of nuclear structures data base. Reconstruction of nuclear structure (ENSDF) data base with up-to-date data. - Establishment of nuclear reaction data base. Collection of the experimental reaction database (EXFOR). Collection of the evaluated nuclear reaction data libraries. Development of data retrieval programs. - Group constant library generation and verification. Generation of MATXS group constant library for thermal reactor application and verification against U-235 cores. Improvement of the cross section library preparation system for the MCNP code. (author). 15 refs., 8 tabs., 8 figs