Kuroda Normal Form

In formal language theory, a grammar is in Kuroda normal form if, and only if, all production rules are of the form:

AB → CD or
A → BC or
A → B
A → α

where A, B, C and D are nonterminal symbols and α is a terminal symbol.

Every grammar in Kuroda normal form is monotonic, and therefore, generates a context-sensitive language. Conversely, every context-sensitive language which does not generate the empty string can be generated by a grammar in Kuroda normal form.

It is named for linguist S.-Y. Kuroda.

Famous quotes containing the words normal and/or form:

    “Insecurity, commonly regarded as a weakness in normal people, is the basic tool of the actor’s trade.”
    —Miranda Richardson (b. 1958)

    “Freedom is the essence of this faith. It has for its object simply to make men good and wise. Its institutions then should be as flexible as the wants of men. That form out of which the life and suitableness have departed should be as worthless in its eyes as the dead leaves that are falling around us.”
    —Ralph Waldo Emerson (1803–1882)