IJPAM: Volume 59, No. 3 (2010)




Jeppiaar Nagar, Chennai-119, TN, INDIA
e-mail: shirley_gloria2976@yahoo.com

Women's Christian College
Chennai-6, TN, INDIA
e-mail: beulah.immanuel@gmail.com

Bharath University
Selaiyur, Chennai-73, TN, INDIA
e-mail: kr2210@hotmail.com
Abstract.Parallel context-free languages are generated by parallel context-free
grammars. We have proved that every parallel context free languages
can be generated by string-token Petri net. We have constructed string
token Petri nets to accept the union and concatenation of family of
parallel context-free languages. It is also proved that the family of
parallel context-free languages is contained in the family of context
sensitive languages.
Received: January 4, 2010
AMS Subject Classification: 03H10, 90A16, 26A33
Key Words and Phrases: string-token Petri net (STPN), context-free languages (CFL), parallel context free languages (PCL), linear bounded automaton (lba), context sensitive languages (CSL)
Source: International Journal of Pure and Applied Mathematics
ISSN: 1311-8080
Year: 2010
Volume: 59
Issue: 3