中文摘要：

使用过程中数字权利的动态描述一直都是DRM应用系统研究的热点。提出一种基于逻辑推理的数字权利动态描述模型，在定义好该模型的基本要素以后，利用逻辑推理工具Prolog深入探讨和分析该模型中数字证书逻辑推理过程，并给出了相应的应用实例。

英文摘要：

At all times, dynamic expression of digital rights during the usage is always the focus in DRM. This paper demonstrated a kind of model in dynamic expression of digital rights based logic reasoning. After defining the relcvent essential elements of this model, it deeply explored and analyzed logic reasoning process of the digital certificate in this model with Prolog. Finally,presented a pertinent application example.