DDJ has the feature of assembling the multi-element and the function of treating the master-slave relation between structure nodes and there are equipped with the data-base softwares for the structures and loads. DDJ程序具有多种单元组装能力和处理节点变位主从关系的功能,并配有对描述结构本身特点原始数据的管理软件和载荷数据管理软件。