closed system

详细解释:【计】 闭合系统
【化】 封闭系统
【经】 闭锁制度

例句：

The purpose of this seminar is to reform the old closed system so as to establish the new system of educational assessment.研讨会旨在改革旧的封闭式的评价制度，从而建立新的教育评价体系。