Concept of Linear Bounded Automata, Finite Automata with External Storage

Linear bounded automata (LBA):

The linear bounded automaton is a finite automaton with read or write access to a tape T of fixed length recognized by the input string w. M has a read or write head which can be moved left or right one square at a time, however can’t be moved off the tape. The name ‘linear bounded’ signifies to the fact that T’s storage capacity is a constant multiple of capacity needed to hold w.

M consists of a working alphabet B that contains A as a subset, and usually has additional characters utilized for scratch work and book-keeping. In the illustration of figure at left, A = {0, 1}, B = {0, 1, %, ...}. The tape of length L has a storage capacity of L log |B| bits that is a constant factor of log |B| / log |A| bigger than the storage capacity needed to store input strings over A of similar length L . This is convenient to think of M’s tape as comprising of several parallel tracks, as shown at right. The designated track comprises the input string to be processed, and may be read-only. The other tracks are read or write tracks employed for scratch work. In this model, M’s alphabet is the Cartesian product A x B’ x B” x ..of input alphabet A and other track alphabets B’, B”, ..

2474_linear bounded automata.jpg

A deterministic LBA has the components: M = (Q, A, B, f: Q x B -> Q x B x {L, R, H,..}, q0, F}.

Q: finite state space; A: input alphabet and B tape alphabet; f: transition function; q0: initial state; F: final states.

{L, R, H, ..}: tape actions: L = move left, R = move right, H = halt and Optional: “stay put”.

Problem: The word problem for LBAs is decidable.

Illustrate the decision procedure which, given an LBA M and a word w, decides whether M accepts w.

Latest technology based Theory of Computation Online Tutoring Assistance

Tutors, at the www.tutorsglobe.com, take pledge to provide full satisfaction and assurance in Theory of Computation help via online tutoring. Students are getting 100% satisfaction by online tutors across the globe. Here you can get homework help for Theory of Computation, project ideas and tutorials. We provide email based Theory of Computation help. You can join us to ask queries 24x7 with live, experienced and qualified online tutors specialized in Theory of Computation. Through Online Tutoring, you would be able to complete your homework or assignments at your home. Tutors at the TutorsGlobe are committed to provide the best quality online tutoring assistance for Theory of Computation Homework help and assignment help services. They use their experience, as they have solved thousands of the Theory of Computation assignments, which may help you to solve your complex issues of Theory of Computation. TutorsGlobe assure for the best quality compliance to your homework. Compromise with quality is not in our dictionary. If we feel that we are not able to provide the homework help as per the deadline or given instruction by the student, we refund the money of the student without any delay.

©TutorsGlobe All rights reserved 2022-2023.