标记辩论推理系统

A CUMULATIVE ARGUMENT SYSTEM

Lin提出的辩论推理系统为非单调推理形式提供了一种统一的基础，其推理机制由所谓的论点结构实现．由Lin的系统导出的非单调推理并不具有累加性，而该性质是衡量一个非单调推理关系的重要标志之一．利用Brewka的方法，本文提出标记辩论推理的概念，并且证明缺省逻辑CDL可以嵌入本系统，从而也间接地给出了标记辩论系统具有累加性的一种充分条件．为了彻底地恢复累加性，本文提出了强封闭论点结构的概念，且由标记辩论系统的强封闭论点结构定义的非单调推理具有累加性．

Lin and Shoham's argument system provides a unifying basis for various monotonic formalism, in which the inference is performed by the so-called argument structures. The authors observed, however, that the inference relation induced by their argument system is not cumulative in general. By employing a technique of Brewka's, this paper presents an ASA(argument system with assertions). Though this system is still not cumulative, prove that Brewka's cumulative default logic can be embedded into this system, which provides a sufficient condition for the cumulativity of ASA. To thoroughly retain the cumulativity of this system, the concept of SCAS(strongly closed argument structures) is introduced and it is proved that the inference relation induced by SCAS is cumulative in general.