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Final Sentential Forms and Their Applications
Kožár, Tomáš ; Kövári, Adam (oponent) ; Meduna, Alexandr (vedoucí práce)
Context-free grammars are one of the most used formal models in formal language theory. They have many useful applications, but for many applications, they lack expressive power. We introduce a final language F . When a sentential form of the context-free grammar G belongs to the F , it becomes a final sentential form. By the erasion of the nonterminals from the final sentential forms, we receive a language of G finalized by F , L(G,F) . We prove that for each recursively enumerable language L , there exists context-free grammar G , such that L = L(G,F) , with F = { w#reversal(w) | w is from {0,1}*}, where reversal(w) is a reversal of w . When a regular language is used as F , no increase in generative power compared to context-free grammars is achieved. We show multiple applications of the final sentential forms in the fields of the linguistics and bioinformatics.
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Final Sentential Forms and Their Applications
Kožár, Tomáš ; Kövári, Adam (oponent) ; Meduna, Alexandr (vedoucí práce)
Context-free grammars are one of the most used formal models in formal language theory. They have many useful applications, but for many applications, they lack expressive power. We introduce a final language F . When a sentential form of the context-free grammar G belongs to the F , it becomes a final sentential form. By the erasion of the nonterminals from the final sentential forms, we receive a language of G finalized by F , L(G,F) . We prove that for each recursively enumerable language L , there exists context-free grammar G , such that L = L(G,F) , with F = { w#reversal(w) | w is from {0,1}*}, where reversal(w) is a reversal of w . When a regular language is used as F , no increase in generative power compared to context-free grammars is achieved. We show multiple applications of the final sentential forms in the fields of the linguistics and bioinformatics.
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