The present balanced two-layer sample rotation system is applicable only to the monthly survey with two-stage sample designs and with small primary sampling units.

目前的平衡两层次样本轮换模式只适用于一级单元规模较小时的两阶段抽样月度调查。

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Two stage search and sample match are emphasized in the paper. Then the final BOM is created on base of product model by knowledge and rule base which may decrease plenty of redundant information i…

重点论述了两阶段搜索与简单匹配的配置过程，其特点是减少数据库中存储的大量事实信息，通过知识库、产品配置规则作用从而在产品模型的基础上实现产品的最终BOM（材料明细表）。

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