TY - BOOK A1 - Bensch, Suna A1 - Boldt, Oliver A1 - Bordihn, Henning A1 - Jürgensen, Helmut T1 - Workshop "Formale Methoden der Linguistik" und "14. Theorietag Automaten und Formale Sprachen" T3 - Preprint / Universität Potsdam, Institut für Informatik Y1 - 2004 SN - 0946-7580 VL - 2004, 2 PB - Univ. CY - Potsdam ER - TY - JOUR A1 - Bensch, Suna A1 - Bordihn, Henning A1 - Holzer, Markus A1 - Kutrib, Martin T1 - On input-revolving deterministic and nondeterministic finite automata N2 - We introduce and investigate input-revolving finite automata, which are (nondeterministic) finite state automata with the additional ability to shift the remaining part of the input. Three different modes of shifting are considered, namely revolving to the left, revolving to the right, and circular-interchanging. We investigate the computational capacities of these three types of automata and their deterministic variants, comparing any of the six classes of automata with each other and with further classes of well-known automata. In particular, it is shown that nondeterminism is better than determinism, that is, for all three modes of shifting there is a language accepted by the nondeterministic model but not accepted by any deterministic automaton of the same type. Concerning the closure properties most of the deterministic language families studied are not closed under standard operations. For example, we show that the family of languages accepted by deterministic right-revolving finite automata is an anti-AFL which is not closed under reversal and intersection. Y1 - 2009 UR - http://www.sciencedirect.com/science/journal/08905401 U6 - https://doi.org/10.1016/J.Ic.2009.03.002 SN - 0890-5401 ER - TY - JOUR A1 - Bordihn, Henning T1 - On the number of components in cooperating distributed grammar systems N2 - It is proved that the number of components in context-free cooperating distributed (CD) grammar systems can be reduced to 3 when they are working in the so-called sf-mode of derivation, which is the cooperation protocol which has been considered first for CD grammar systems. In this derivation mode, a component continues the derivation until and unless there is a nonterminal in the sentential form which cannot be rewritten according to that component. Moreover, it is shown that CD grammar systems in sf-mode with only one component can generate only the context-free languages but they can generate non-context-free languages if two components are used. The sf-mode of derivation is compared with other well-known cooperation protocols with respect to the hierarchies induced by the number of components. (C) 2004 Elsevier B.V. All rights reserved Y1 - 2005 SN - 0304-3975 ER - TY - JOUR A1 - Bordihn, Henning T1 - Context-freeness of the power of context-free languages is undecidable N2 - The power of a language L is the set of all powers of the words in L. In this paper, the following decision problem is investigated. Given a context-free language L, is the power of L context-free? We show that this problem is decidable for languages over unary alphabets, but it is undecidable whenever languages over alphabets with at least two letters are considered. (C) 2003 Elsevier B.V. All rights reserved Y1 - 2004 SN - 0304-3975 ER - TY - THES A1 - Bordihn, Henning T1 - Contributions to the syntactical analysis beyond context-freeness T1 - Beiträge zur syntaktischen Analyse nicht-kontextfreier Sprachen N2 - Parsability approaches of several grammar formalisms generating also non-context-free languages are explored. Chomsky grammars, Lindenmayer systems, grammars with controlled derivations, and grammar systems are treated. Formal properties of these mechanisms are investigated, when they are used as language acceptors. Furthermore, cooperating distributed grammar systems are restricted so that efficient deterministic parsing without backtracking becomes possible. For this class of grammar systems, the parsing algorithm is presented and the feature of leftmost derivations is investigated in detail. N2 - Ansätze zum Parsing verschiedener Grammatikformalismen, die auch nicht-kontextfreie Sprachen erzeugen können, werden diskutiert. Chomsky-Grammatiken, Lindenmayer-Systeme, Grammatiken mit gesteuerten Ersetzungen und Grammatiksysteme werden behandelt. Formale Eigenschaften dieser Mechanismen als Akzeptoren von Sprachen werden untersucht. Weiterhin werden kooperierende verteilte (CD) Grammatiksysteme derart beschränkt, dass effizientes deterministisches Parsing ohne Backtracking möglich ist. Für diese Klasse von Grammatiksystemen wird der Parsingalgorithmus vorgestellt und die Rolle von Linksableitungen wird detailliert betrachtet. KW - Parsing KW - Akzeptierende Grammatiken KW - Gesteuerte Ableitungen KW - Grammatiksysteme KW - Linksableitungen KW - Parsing KW - Accepting Grammars KW - Controlled Derivations KW - Grammar Systems KW - Leftmost Derivations Y1 - 2011 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-59719 ER - TY - JOUR A1 - Bordihn, Henning T1 - Active symbols in grammars with valuations JF - Theoretical computer science N2 - Grammars with valuations are context-free rewriting mechanisms where the derivation process is controlled by a recursive function that evaluates strings. They have been introduced by Jurgen Dassow as models for the molecular replication process taking into account its selective character. A symbol is active in a grammar with valuation if it can be rewritten non-identically. This paper studies the effect of restricting the number of active symbols in grammars with valuations and several variants thereof to their generative power. It is investigated in which cases the number of active symbols induces infinite strict hierarchies and when the hierarchies collapse. The induced language families are compared among one another. (C) 2016 Elsevier B.V. All rights reserved. KW - Formal languages KW - Biologically inspired formal systems KW - Descriptional complexity Y1 - 2017 U6 - https://doi.org/10.1016/j.tcs.2016.11.008 SN - 0304-3975 SN - 1879-2294 VL - 682 SP - 42 EP - 48 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Bordihn, Henning A1 - Bottoni, Paolo A1 - Labella, Anna A1 - Mitrana, Victor T1 - Networks of picture processors as problem solvers JF - Soft Computing N2 - We propose a solution based on networks of picture processors to the problem of picture pattern matching. The network solving the problem can be informally described as follows: it consists of two subnetworks, one of them extracts at each step, simultaneously, all subpictures of identical (progressively decreasing) size from the input picture and sends them to the other subnetwork which checks whether any of the received pictures is identical to the pattern. We present an efficient solution based on networks with evolutionary processors only, for patterns with at most three rows or columns. Afterward, we present a solution based on networks containing both evolutionary and hiding processors running in O(n + m + kl) computational (processing and communication) steps, for any size (n, m) of the input pic-ture and (k, l) of the pattern. From the proofs of these results, we infer that any (k, l)-local language with 1 <= k <= 3 can be decided in O(n + m + l) computational steps by networks with evolutionary processors only, while any (k, l)-local language with arbitrary k, l can be decided in O(n + m + kl) computational steps by networks containing both evolutionary and hiding processors. KW - Picture KW - Picture processor KW - Hiding processor KW - Picture matching KW - (k,l)-Local language Y1 - 2016 U6 - https://doi.org/10.1007/s00500-016-2206-y SN - 1432-7643 SN - 1433-7479 VL - 21 SP - 5529 EP - 5541 PB - Springer CY - New York ER - TY - JOUR A1 - Bordihn, Henning A1 - Dassow, Juergen A1 - Holzer, Markus T1 - Extending regular expressions with homomorphic replacement N2 - We define H- and EH-expressions as extensions of regular expressions by adding homomorphic and iterated homomorphic replacement as new operations, resp. The definition is analogous to the extension given by Gruska in order to characterize context-free languages. We compare the families of languages obtained by these extensions with the families of regular, linear context-free, context-free, and EDT0L languages. Moreover, relations to language families based on patterns, multi-patterns, pattern expressions, H-systems and uniform substitutions are also investigated. Furthermore, we present their closure properties with respect to TRIO operations and discuss the decidability status and complexity of fixed and general membership, emptiness, and the equivalence problem. Y1 - 2010 UR - http://www.rairo-ita.org/ U6 - https://doi.org/10.1051/Ita/2010013 SN - 0988-3754 ER - TY - JOUR A1 - Bordihn, Henning A1 - Fernau, Henning A1 - Holzer, Markus A1 - Manca, Vincenzo A1 - Martin-Vide, Carlos T1 - Iterated sequential transducers as language generating devices JF - Theoretical computer science N2 - Iterated finite state sequential transducers are considered as language generating devices. The hierarchy induced by the size of the state alphabet is proved to collapse to the fourth level. The corresponding language families are related to the families of languages generated by Lindenmayer systems and Chomsky grammars. Finally, some results on deterministic and extended iterated finite state transducers are established. KW - finite state sequential transducers KW - state complexity KW - Lindenmayer systems Y1 - 2006 U6 - https://doi.org/10.1016/j.tcs.2006.07.059 SN - 0304-3975 VL - 369 IS - 1 SP - 67 EP - 81 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Bordihn, Henning A1 - Holzer, Markus T1 - Programmed grammars and their relation to the LBA problem JF - Acta informatica N2 - We consider generating and accepting programmed grammars with bounded degree of non-regulation, that is, the maximum number of elements in success or in failure fields of the underlying grammar. In particular, it is shown that this measure can be restricted to two without loss of descriptional capacity, regardless of whether arbitrary derivations or left-most derivations are considered. Moreover, in some cases, precise characterizations of the linear bounded automaton problem in terms of programmed grammars are obtained. Thus, the results presented in this paper shed new light on some longstanding open problem in the theory of computational complexity. KW - programmed grammars KW - accepting grammars KW - LBA problem KW - degree of non-regulation KW - leftmost derivations Y1 - 2006 U6 - https://doi.org/10.1007/s00236-006-0017-9 SN - 0001-5903 VL - 43 SP - 223 EP - 242 PB - Elsevier CY - New York ER -