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Universal automata with uniform bounds on simulation time

W. Menzel, V. Sperschneider
1982 Information and Control  
LOCAL SIMULATION WITH UNIFORM BOUNDS Definition For automata f and U, injective cr E R i and b E R 1, we say that U locally simulates f via a with time bound b iff for all z, z' E N: f(z) = z' ~ ~t[l  ...  Theorem 3 says that no globally universal automata exist with time bounds uniformly obtainable from the given automata f We conclude with some remarks regarding the literature and a comprehensive summary  ...  This, of course, implies that U is globally universal with fixed codings.  ... 
doi:10.1016/s0019-9958(82)80083-1 fatcat:usnxpb5k4rdgli54ikjehm22ca

Page 3362 of Mathematical Reviews Vol. , Issue 84h [page]

1984 Mathematical Reviews  
Next, global simulation with uniform bounds is defined, and it is shown that there is no uniform bound on the loss of time incurred when some universal automaton globally simulates another automaton.  ...  .; Sperschneider, V. 84h:68040 Universal automata with uniform bounds on simulation time. Inform. and Control 52 (1982), no. 1, 19-35. Following B. Buchberger and B. Roider [Internat. J. Gen.  ... 

Alternation on cellular automata

Martín Matamala
1997 Theoretical Computer Science  
It is proved that real time alternation in cellular automata is strictly more powerful than real time alternation in Turing machines, with only one read-write tape.  ...  In this paper we consider several notions of alternation in cellular automata: non-uniform, uniform and weak alternation. We study relations among these notions and with alternating Turing machines.  ...  It is easy to see that this simulation can be extended to uniform cellular automata and nonuniform ones. So, polynomial time restrictions are equivalent in all models.  ... 
doi:10.1016/s0304-3975(96)00214-9 fatcat:f4yorvpomfbrncb7sh6mgsbqki

Real-Time Language Recognition by Alternating Cellular Automata [chapter]

Thomas Buchholz, Andreas Klein, Martin Kutrib
2000 Lecture Notes in Computer Science  
Our investigations center on space bounded real-time com putations.  ...  Comparing ACAs with deter ministic CAs it is shown that real-time ACAs are strictly more powerful than real-time CAs.  ...  Acknowledgements The authors are grateful to Thomas Worsch for valuable comments on the proof of Theorem 8.  ... 
doi:10.1007/3-540-44929-9_17 fatcat:ybki742v6ves5n52zm4kx2ov64

On the complexity of two-dimensional signed majority cellular automata

Eric Goles, Pedro Montealegre, Kévin Perrot, Guillaume Theyssier
2018 Journal of computer and system sciences (Print)  
We use this to establish new bounds on their overall complexity, concretely: the uniform asymmetric and the non-uniform symmetric rules are Turing universal and have a P-complete prediction problem; the  ...  We show that, depending on their symmetry and uniformity, they can simulate different types of logical circuitry under different modes.  ...  He proved that in a bounded one-dimensional threshold automata every possible cycle has period less than four and in the two dimensional case there exists a bounded asymmetric threshold automaton with  ... 
doi:10.1016/j.jcss.2017.07.010 fatcat:74cf3zid3jdqhgyxyvsqeugvka


Matthew Cook, Turlough Neary
2019 Natural Computing  
,-volV) Publisher's Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.  ...  The paper ''Cellular Automata on Group Sets and the Uniform Curtis-Hedlund-Lyndon Theorem'' by Simon Wacker generalizes some well-known results to a more general setting.  ...  It is shown that the structure of the group of invertible cellular automata may be expressed as wreath products and in a related result a new lower bound on the number of aperiodic configurations is given  ... 
doi:10.1007/s11047-019-09744-8 fatcat:x24gzcllxzdsvf2hfu7it77g4i

Alternating and empty alternating auxiliary stack automata

Markus Holzer, Pierre McKenzie
2003 Theoretical Computer Science  
We consider variants of alternating auxiliary stack automata and characterize their computational power when the number of alternations is bounded by a constant or unlimited.  ...  In this way we get new characterizations of NP, the polynomial hierarchy, PSpace, and bounded query classes like co-DP =NL NP[1] and 2P =P NP[O(log n)] , in a uniform framework.  ...  Also thanks to an anonymous referee for his valuable comments on Section 4, including the observation that some of our earlier arguments (now corrected) did not apply to nonlogarithmic space bounds directly  ... 
doi:10.1016/s0304-3975(02)00326-2 fatcat:rsn7jmav2bg2ljt3u3jijrohqy

Properties of probabilistic pushdown automata

Ioan I. Macarie, Mitsunori Ogihara
1998 Theoretical Computer Science  
Also, complexity lower bounds are given for the classes of languages recognized by these automata with unlimited running time.  ...  Complete characterizations in terms of well-known complexity classes are given for the classes of languages recognized by polynomial time-bounded, logarithmic space-bounded auxiliary pushdown automata  ...  Acknowledgements The first author is grateful to Eric Allender for enjoyable discussions on this topic.  ... 
doi:10.1016/s0304-3975(98)00059-0 fatcat:wblsfvu4urfxhj4p2vz3pjopiy

Multi-head finite automata: data-independent versus data-dependent computations

Markus Holzer
2002 Theoretical Computer Science  
We develop a multi-head ÿnite automata framework suitable for a more detailed study of the relationship between parallel logarithmic time and sequential logarithmic space, in the uniform and nonuniform  ...  captured with data-dependent computations on multi-head ÿnite state machines.  ...  We also thank the unknown referees for making suggestions on the readability of the paper.  ... 
doi:10.1016/s0304-3975(01)00237-7 fatcat:ky2ry42ybrfbxbx3iyc5qk7dwi

On the Complexity of Intersecting Regular, Context-Free, and Tree Languages [chapter]

Joseph Swernofsky, Michael Wehar
2015 Lecture Notes in Computer Science  
Then, for every k, we reduce intersection non-emptiness for one PDA and 2 k DFA's to non-emptiness for multi-stack pushdown automata with k-phase switches to obtain a tight time complexity lower bound.  ...  We show that there exist constants c 1 and c 2 such that for every k, intersection non-emptiness for k tree automata is solvable in O(n c 1 k ) time, but is not solvable in O(n c 2 k ) time.  ...  We would especially like to thank Richard Lipton, Kenneth Regan, Atri Rudra, and all those from Carnegie Mellon University who were supportive of our research work while we were undergraduates.  ... 
doi:10.1007/978-3-662-47666-6_33 fatcat:mouw5gqgubbito6x5yfpdkrrdy

Multi-head finite automata: Data-independent versus data-dependent computations [chapter]

Markus Holzer
1997 Lecture Notes in Computer Science  
We develop a framework on multi-head nite automata that allows us to study the relation of parallel logarithmic time and sequential logarithmic space in a uniform and nonuniform setting in more detail.  ...  In both settings it turns out that NC 1 requires data-independent computations|the movement of the input-heads only depends on the length of the input|whereas logarithmic space is caught with datadependent  ...  Lange for valuable hints and comments on that topic. Also thanks to P. McKenzie for a discussion on that topic.  ... 
doi:10.1007/bfb0029973 fatcat:c4ilvb5zxndz5ffrzbxaisbhsy

Computability and Non-computability Issues in Amorphous Computing [chapter]

Jiří Wiedermann
2012 Lecture Notes in Computer Science  
We will argue that the amorphous systems belong among the simplest (non-uniform) universal computational devices.  ...  power with a high probability.  ...  Although the whole system can correctly simulate a RAM (with a bounded memory size) with arbitrary high probability, the simulation time cannot be bounded by any function.  ... 
doi:10.1007/978-3-642-33475-7_1 fatcat:jjfcqvhiizcvrolws2up2vz5si

How We Think of Computing Today [chapter]

Jiří Wiedermann, Jan van Leeuwen
2008 Lecture Notes in Computer Science  
We propose two models inspired from key mechanisms of current systems in both artificial and natural environments: evolving automata and interactive Turing machines with advice.  ...  , and the shift to computing systems that evolve in an unpredictable, non-uniform way.  ...  Running this machine on input M in parallel with the simulation of the w, I has an upper bound on the running time on w within which the machine must halt on its own description when it does.  ... 
doi:10.1007/978-3-540-69407-6_61 fatcat:5y34z2r6afbtjms3jor33i5hia

Page 4806 of Mathematical Reviews Vol. , Issue 86j [page]

1986 Mathematical Reviews  
Author summary: “Let Sp(dV) denote the class of spectra of first-order sentences with d universal quantifiers.  ...  Author summary: “We show that a probabilistic Turing acceptor or transducer running within space bound S can be simulated by a time S? parallel machine and therefore by a space S?  ... 

State equivalences for rectangular hybrid automata [chapter]

Thomas A. Henzinger, Peter W. Kopke
1996 Lecture Notes in Computer Science  
We characterize the time-abstract versions of these equivalence relations on the state spaces of rectangular hybrid automata (RHA), in which each continuous variable is a clock with bounded drift.  ...  When bounds on the number of equivalence classes are obtained, bounds on the running times of model checking and synthesis algorithms follow as corollaries.  ...  One-sided Timed Automata Let T be an (n + m)-dimensional one-sided timed automaton with n upper-bounded clocks and m lower-bounded clocks.  ... 
doi:10.1007/3-540-61604-7_74 fatcat:ky5jee7apferxmdc7ld3wfci4y
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