This volume contains the proceedings of EXPRESS/SOS 2020: the Combined 27th International Workshop on Expressiveness in Concurrency and the 17th Workshop on Structural Operational Semantics, which was held online, as an affiliated workshop of CONCUR 2020, the 31st International Conference on Concurrency Theory. The EXPRESS/SOS workshop series aims at bringing together researchers interested in the formal semantics of systems and programming concepts, and in the expressiveness of computational models.

中文翻译：

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第 27 届并发表达性国际研讨会和第 17 届结构操作语义研讨会的论文集

本卷包含 EXPRESS/SOS 2020：第 27 届并发表达性国际研讨会和第 17 届结构操作语义联合研讨会的会议记录，该研讨会作为第 31 届并发理论国际会议 CONCUR 2020 的附属研讨会在线举行。EXPRESS/SOS 研讨会系列旨在汇集对系统和编程概念的形式语义以及计算模型的表达性感兴趣的研究人员。