A two-sided extension of strictly locally testable languages is presented. In order to determine membership within a two-sided strictly locally testable language, the input must be scanned from both ends simultaneously, whereby it is synchronously checked that the factors read are correlated with respect to a given binary relation. The class of two-sided strictly locally testable languages is shown to be a proper subclass of the even linear languages that is incomparable to the regular languages with respect to inclusion. Furthermore, closure properties of the class of two-sided strictly locally testable languages and decision problems are studied. Finally, it is shown that two-sided strictly k-testable languages are learnable in the limit from positive data.

中文翻译：

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双向严格本地可测试的语言

提供了严格本地可测试语言的双向扩展。为了确定严格在本地可测试的双向语言中的成员资格，必须同时从两端扫描输入，从而同步检查所读取的因子是否与给定的二进制关系相关。双向严格本地可测试的语言类别显示为偶数线性语言的适当子类，就包容性而言，它们与常规语言无法比拟。此外，还研究了两类严格本地可测试语言的闭包性质和决策问题。最后，证明了从正数据角度来看，可以严格学习k检验的双面语言。