Table schema:
CREATE TABLE table_name_31 (english_name VARCHAR, provider_national_government_ VARCHAR, abbreviation VARCHAR)

Question: What is the english name of the ministry of defense with an abbreviation of nda bōei-dai(防衛大)?
SQL: SELECT english_name FROM table_name_31 WHERE provider_national_government_ = "ministry of defense" AND abbreviation = "nda bōei-dai(防衛大)"