IDEOGRAPH VARIANT FORMS AND USAGE CONTROL IN NACSIS-CAT.

The article provides information on the character set usage control in NACSIS-CAT cataloging system, a shared cataloging system used by the Council of East Asian Libraries. The NACSIS-CAT is a shared cataloging system, similar to the Online Computer Library Catalog and Research Library Information Network cataloging systems, operated by the National Institute of Informatics Japan. It is developed by the Center for Bibliographic Information at the University of Tokyo to provide information resources for research activities. The NACSIS-CAT has a mechanism of character set usage control that limits the usage of certain characters in the character set and unify then with other characters in the set.