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Remarks on multihead pushdown automata and multihead stack automata

Satoru Miyano
1983 Journal of computer and system sciences (Print)  
.MIMt =7 + ii' aJaqM '7 a%ntausl uoletuolnt? (~3~1s .dSaJ) umopysnd peaq!llnm kt?M-atI0 XUOS JOJ 7 + se uall!JM aq ue3 qJ!qM Qxaldmoz aDeds pue arug )sapJeq aq] q]!M a%tXd?LK?~ e s!  ...  wauu%a Ouguno3 aql pue Jamod uop!u%oc3a.I aql sask?aKXI! ptFaq yndu! p~~og!ppe ue v3ql allold 01 ew.uouIe LT?M -0~1 JOJ pasn s! luaun&E uoy~z~~auo%e~p aq1 'Qt3nsn wtrurow yws peaq!ynw put?  ...  ACKNOWLEDGMENTS The author is grateful to Setsuo Arikawa and Takeshi Hayashi for many inspiring conversations about hardest languages and to an anonymous referee for his suggestions on the proof of Theorem  ... 
doi:10.1016/0022-0000(83)90032-6 fatcat:c7w5x2kvmfd3dc2dqcg3qepa7u

Page 2949 of Mathematical Reviews Vol. , Issue 83h [page]

1983 Mathematical Reviews  
We also investigate closure properties of the class of rebound automata.” 83g:68117 Miyano, Satoru 83g:68118 A hierarchy theorem for multihead stack-counter automata.  ...  As a corollary, we show that k+ | heads are better than k for one-way multihead stack-counter automata.” Nasyrov, L. R. 83g:68119 A reduction theorem for automata over trees.  ... 

One-reversal counter machines and multihead automata: Revisited

Ehsan Chiniforooshan, Mark Daley, Oscar H. Ibarra, Lila Kari, Shinnosuke Seki
2012 Theoretical Computer Science  
Non-deterministic counter machines with a pushdown stack are then compared with multihead finite automata.  ...  ) and one-way multihead finite automata (finite automata with multiple one-way input heads) as a language acceptor.  ...  Acknowledgments We wish to thank anonymous referees for their critical comments and suggestions on the earlier version of this paper.  ... 
doi:10.1016/j.tcs.2012.04.002 fatcat:fbw7imfcqbe7np5d4k4o4wr4m4

Page 5145 of Mathematical Reviews Vol. , Issue 85k [page]

1985 Mathematical Reviews  
A hierarchy for one-way multihead automata follows from the known hierarchy theorems for two-way devices. The author also describes “hardest” sets for multihead two-way automata families.  ...  {For the entire collection see MR 85e:68003. } Miyano, Satoru (J-KYUS) 85k:68027 Remarks on multihead pushdown automata and multihead stack automata. J. Comput. System Sci. 27 (1983), no. 1, 116-124.  ... 

Hierarchies of one-way multihead automata languages

Marek Chrobak
1986 Theoretical Computer Science  
The main result of this paper is that, for every k > 0, DPDA(k ) ~ DPDA(k + 1) and DPDA(k ) ~ NPDA(k).  ...  Let DPDA(k) (respectively NPDA(k)) be the class of languages recognized by one-way k-head deterministic (respectively nondeterministic) pushdown automata.  ...  Hierarchies for finite and counter automata Theorem 7.1. For every k > 0, 1 t> 0, DPDA(k, l) c~ B2 G DPDA(k + 1, I) n B2. Proof.  ... 
doi:10.1016/0304-3975(86)90093-9 fatcat:mwo4ha3f25ahjf4dxe5epdfnd4

Page 5113 of Mathematical Reviews Vol. , Issue 83m [page]

1983 Mathematical Reviews  
Authors’ summary: “The two main results of the paper are: (1) a refinement of the hierarchy of reversal-bounded counter machine languages due to T. H.  ...  The 2npda(k) A is said to be H(n) stack bounded if for every word accepted by A there is an accepting computation of A in which the height of the stack does not exceed H(n).  ... 

Stack versus sensitivity for one-way automata

Mirosław Kutyłowski
1993 Theoretical Computer Science  
M., Stack versus sensitivity for one-way automata, Theoretical Computer Science 119 (1993) 2-33-245.  ...  We consider one-way multihead automata recognizing 2-bounded languages, i.e., languages L such that Ls 1*2*.  ...  Some problems have the same solutions for bounded and not-bounded languages, but the proof techniques involved are quite different (see the hierarchy problem for one-way multihead finite automata [ 1,  ... 
doi:10.1016/0304-3975(93)90158-p fatcat:cb7xlggrefepdam4ajeqroltqq

Synchronized finite automata and 2DFA reductions

Oscar H. Ibarra, Nicholas Q. Trân
1993 Theoretical Computer Science  
In fact, even under the severe restriction of the pushdown store to a counter making only one reversal, synchronized pushdown automata still recognize all recursively enumerable languages.  ...  We establish a tight hierarchy of two-way synchronized finite automata with only universal states on the number of allowed processes (Y(ZSUFA(k-proc)) c Y(ZSUFA((k+ 1)-proc))) by studying the reduction  ...  Acknowledgment We thank Tao Jiang for a very careful reading of a preliminary version of this paper. Valuable discussion with him led to the proof of Theorem 5.10.  ... 
doi:10.1016/0304-3975(93)90119-e fatcat:modntx754za6jdaf6hypcngyvu

One-Reversal Counter Machines and Multihead Automata: Revisited [chapter]

Ehsan Chiniforooshan, Mark Daley, Oscar H. Ibarra, Lila Kari, Shinnosuke Seki
2011 Lecture Notes in Computer Science  
automata with multiple counters, where each counter can only "reverse" once, i.e., once a counter decrements, it can no longer increment).  ...  Among the many models of language acceptors that have been studied in the literature are multihead finite automata (finite automata with multiple one-way input heads) and 1-reversal counter machines (finite  ...  From Corollary 1 and Theorem 2, we have: Counter Machines and Multihead Automata A (non-deterministic) multihead finite automaton (NMHFA) M with k heads (written as NMHFA(k)) is a machine with k one-way  ... 
doi:10.1007/978-3-642-18381-2_14 fatcat:wqv5lj22grc6hgjq2emfdcdhpy

The Power of Centralized PC Systems of Pushdown Automata [chapter]

Holger Petersen
2013 Lecture Notes in Computer Science  
A claimed converse simulation for returning mode (Balan 2009) turned out to be incomplete (Otto 2012) and a language was suggested for separating these PCPA of degree two (number of pushdown automata)  ...  Finally PCPAs are restricted in such a way that a simulation by multi-head automata is possible.  ...  Discussion We have settled the open problem about the power of centralized PC systems of pushdown automata (PCPA) working in returning mode from [7] .  ... 
doi:10.1007/978-3-642-39310-5_23 fatcat:rgsqeqzjs5hiziiy4igebr2bg4

Page 2175 of Mathematical Reviews Vol. , Issue 82e [page]

1982 Mathematical Reviews  
In this paper we show under the same condition that L, cannot be recognized by any one-way k-head stack-counter automaton and we obtain a hierarchy theorem.”  ...  Anisimov (Kiev) Miyano, Satoru 82e:68091 k+ 1 heads are better than k for one-way multihead stack-counter automata. Res. Inst. Fund. Inform. Sci. Res. Rep. No. 98 (1980), ii+7 pp.  ... 

Iterated stack automata and complexity classes

Joost Engelfriet
1991 Information and Computation  
ITERATED STACK AUTOMATA The results of this section can be stated in one sentence: for 2-way multihead automata and for auxiliary SPACE(s(n)) automata, a stack has the same power as a pushdown of pushdowns  ...  counter.  ... 
doi:10.1016/0890-5401(91)90015-t fatcat:o5cnyhrwz5eerkvulkrkjuw5sa

Stateless multicounter 5′ → 3′ Watson–Crick automata: the deterministic case

László Hegedüs, Benedek Nagy, Ömer Eğecioğlu
2011 Natural Computing  
A counter machine is k-reversal if each counter makes at most k alternations between increasing mode and decreasing mode on any computation, and reversal bounded if it is k-reversal for some k.  ...  We give examples and establish hierarchies with respect to counters and reversals.  ...  prove the hierarchy results with respect to realtime stateless multicounter WK-automata as given in Theorem 9.  ... 
doi:10.1007/s11047-011-9290-9 fatcat:gnq635x66nbtxnafp7nklwf3vm

A Survey of Neural Networks and Formal Languages [article]

Joshua Ackerman, George Cybenko
2020 arXiv   pre-print
This report is a survey of the relationships between various state-of-the-art neural network architectures and formal languages as, for example, structured by the Chomsky Language Hierarchy.  ...  Of particular interest are the abilities of a neural architecture to represent, recognize and generate words from a specific language by learning from samples of the language.  ...  Accordingly, counter machines are simply finite automata which have access to a finite number of counting devices [15] .  ... 
arXiv:2006.01338v1 fatcat:wo6qeg6jvnccpbhoiogkhnw364

Cyclic automata

Max Garzon
1987 Theoretical Computer Science  
There is an infinite hierarchy of cyclic graph languages and although most decision problems are decidab' for l-pebble cyclic automata, they are recursively unsolvable for 2-pebble automata.  ...  A cyclic graph language is accepted by a Cayley automston [2 3 with pebbles if and only if their orders can be recognized in logspace by an ordinary Turing machine.  ...  unsolvable for deterministio at a 2-60 ter e The present re uction of 7TO-members roblem of 2-counter finite automata consists in exhibiting an 2-pebble deterministic cyclic aton from a given 2-counter  ... 
doi:10.1016/0304-3975(87)90071-5 fatcat:4wm4idedebcztg6y7df7fxhvbq
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