State-deterministic Finite Automata with Translucent Letters and Finite Automata with Nondeterministically Translucent Letters

Deterministic and nondeterministic finite automata with translucent letters were introduced by Nagy and Otto more than a decade ago as Cooperative Distributed systems of a kind of stateless restarting automata with window size one. These finite state machines have a surprisingly large expressive power: all commutative semi-linear languages and all rational trace languages can be accepted by them including various not context-free languages. While the nondeterministic variant defines a language class with nice closure properties, the deterministic variant is weaker, however it contains all regular languages, some non-regular context-free languages, as the Dyck language, and also some languages that are not even context-free. In all those models for each state, the letters of the alphabet could be in one of the following categories: the automaton cannot see the letter (it is translucent), there is a transition defined on the letter (maybe more than one transitions in nondeterministic case) or none of the above categories (the automaton gets stuck by seeing this letter at the given state and this computation is not accepting). State-deterministic automata are recent models, where the next state of the computation determined by the structure of the automata and it is independent of the processed letters. In this paper our aim is twofold, on the one hand, we investigate state-deterministic finite automata with translucent letters. These automata are specially restricted deterministic finite automata with translucent letters. In the other novel model we present, it is allowed that for a state the set of translucent letters and the set of letters for which transition is defined are not disjoint. One can interpret this fact that the automaton has a nondeterministic choice for each occurrence of such letters to see them (and then erase and make the transition) or not to see that occurrence at that time. Based on these semi-translucent letters, the expressive power of the automata increases, i.e., in this way a proper generalization of the previous models is obtained.Comment: In Proceedings AFL 2023, arXiv:2309.0112

26. Theorietag Automaten und Formale Sprachen 23. Jahrestagung Logik in der Informatik: Tagungsband

Der Theorietag ist die Jahrestagung der Fachgruppe Automaten und Formale Sprachen der Gesellschaft für Informatik und fand erstmals 1991 in Magdeburg statt. Seit dem Jahr 1996 wird der Theorietag von einem eintägigen Workshop mit eingeladenen Vorträgen begleitet. Die Jahrestagung der Fachgruppe Logik in der Informatik der Gesellschaft für Informatik fand erstmals 1993 in Leipzig statt. Im Laufe beider Jahrestagungen finden auch die jährliche Fachgruppensitzungen statt. In diesem Jahr wird der Theorietag der Fachgruppe Automaten und Formale Sprachen erstmalig zusammen mit der Jahrestagung der Fachgruppe Logik in der Informatik abgehalten. Organisiert wurde die gemeinsame Veranstaltung von der Arbeitsgruppe Zuverlässige Systeme des Instituts für Informatik an der Christian-Albrechts-Universität Kiel vom 4. bis 7. Oktober im Tagungshotel Tannenfelde bei Neumünster. Während des Tre↵ens wird ein Workshop für alle Interessierten statt finden. In Tannenfelde werden • Christoph Löding (Aachen) • Tomás Masopust (Dresden) • Henning Schnoor (Kiel) • Nicole Schweikardt (Berlin) • Georg Zetzsche (Paris) eingeladene Vorträge zu ihrer aktuellen Arbeit halten. Darüber hinaus werden 26 Vorträge von Teilnehmern und Teilnehmerinnen gehalten, 17 auf dem Theorietag Automaten und formale Sprachen und neun auf der Jahrestagung Logik in der Informatik. Der vorliegende Band enthält Kurzfassungen aller Beiträge. Wir danken der Gesellschaft für Informatik, der Christian-Albrechts-Universität zu Kiel und dem Tagungshotel Tannenfelde für die Unterstützung dieses Theorietags. Ein besonderer Dank geht an das Organisationsteam: Maike Bradler, Philipp Sieweck, Joel Day. Kiel, Oktober 2016 Florin Manea, Dirk Nowotka und Thomas Wilk

Proving the power of postselection

It is a widely believed, though unproven, conjecture that the capability of postselection increases the language recognition power of both probabilistic and quantum polynomial-time computers. It is also unknown whether polynomial-time quantum machines with postselection are more powerful than their probabilistic counterparts with the same resource restrictions. We approach these problems by imposing additional constraints on the resources to be used by the computer, and are able to prove for the first time that postselection does augment the computational power of both classical and quantum computers, and that quantum does outperform probabilistic in this context, under simultaneous time and space bounds in a certain range. We also look at postselected versions of space-bounded classes, as well as those corresponding to error-free and one-sided error recognition, and provide classical characterizations. It is shown that $\mathsf{NL}$ would equal $\mathsf{RL}$ if the randomized machines had the postselection capability.Comment: 26 pages. This is a heavily improved version of arXiv:1102.066

Tehokas sisäänpäindeterministisiin automaatteihin perustuva Constraint Grammar -jäsennin

Proceeding volume: 14 (2011)Pappret conceptualizes parsning med Constraint Grammar på ett nytt sätt som en process med två viktiga representationer. En representation innehåller lokala tvetydighet och den andra sammanfattar egenskaperna hos den lokala tvetydighet klasser. Båda representationer manipuleras med ren finite-state metoder, men deras samtrafik är en ad hoc -tillämpning av rationella potensserier. Den nya tolkningen av parsning systemet har flera praktiska fördelar, bland annat det inåt deterministiska sättet att beräkna, representera och räkna om alla potentiella tillämpningar av reglerna i meningen.Paperi uudelleenkonseptualisoi Constraint Grammarin sellaisena viitekehyksenä, jossa säännöt tarkentavat paikallisen ambiguiteetin tiivistä esitysmuotoa samalla kun sääntöjen ehdot sovitetaan piirrevektoreita vasten, jotka esittävät tiivistetyjen esitysmuotojen summia. Molemmat näkökulmat monitulkintaisuuteen käsitellään käyttäen puhtaita (pure) äärellistilaisia operaatioita. Tiivis esitysmuoto kuvataan piirrevektoreihin rationaalisten potenssisarjojen avulla. Tämä yhteys ei ole yhtään vähemmän puhdas kuin aikaisemmin vallalla ollut tulkinta, jonka edellyttää että leksikaalisen transduktorin tuottama sanan luentajoukko maagisesti linearisoidaan merkatuksi luentojen peräkkäinasetteluksi, joka syötetään puhtaille (äärellistilaisille) transduktoreille. Esitetyllä lähestymistavalla on useita käytännöllisiä etuja: mm. sisäänpäin deterministinen tapa laskea, esittää ja ylläpitää kaikki mahdolliset kohdat, joissa säännöt voivat soveltua virkkeeseen.The paper reconceptualizes Constraint Grammar as a framework where the rules refine the compact representations of local ambiguity while the rule conditions are matched against a string of feature vectors that summarize the compact representations. Both views to the ambiguity are processed with pure finite-state operations. The compact representations are mapped to feature vectors with the aid of a rational power series. This magical interconnection is not less pure than a prevalent interpretation that requires that the reading set provided by a lexical transducer is magically linearized to a marked concatenation of readings given to pure transducers. The current approach has several practical benefits, including the inward deterministic way to compute, represent and maintain all the applications of the rules in the sentence.Peer reviewe

Prostredie pre reštartovacie automaty

Reštartovacie automaty sú lingvisticky motivované modely automatov, ktoré môžu byť použité napríklad na kontrolu správnosti viet. Hlavným cieľom tejto práce je vytvoriť špecializovaný program, ktorý umožní jednoduchý interaktívny návrh a testovanie týchto automatov a poskytne špecializované nástroje určené na učenie konečných automatov a definovanie jazykov. Práca prezentuje teoretické základy a uvádza formálnu definíciu reštartovacieho automatu. Ďalej sú v práci diskutované možnosti implementácie takéhoto systému a je popísaná skutočná realizácia systému. K práci je priložená užívateľská príručka.Restarting automata are linguistically motivated models of automata that can be used e.g. in checking correctness of a sentence. The main subject of this work is to design a specialized program which allows an easy design and testing of these automata and provides specialized tools for learning finite automata and defining languages. The thesis presents theoretical background and gives formal definition of restarting automaton. Then the possibilities of implementation of such system are discussed and the actual implementation is described. The user guide is included in the thesis.Katedra softwaru a výuky informatikyDepartment of Software and Computer Science EducationFaculty of Mathematics and PhysicsMatematicko-fyzikální fakult

Clearing Restarting Automata

Restartovací automaty byly navrženy jako model pro redukční analýzu, která představuje lingvisticky motivovanou metodu pro kontrolu korektnosti věty. Cílem práce je studovat omezenější modely restartovacích automatů, které smí vymazat podřetězec nebo jej nahradit speciálním pomocným symbolem, jenom na základě omezeného lokálního kontextu tohoto podřetězce. Tyto restartovací automaty se nazývají clearing restarting automata. V práci jsou taktéž zkoumány uzávěrové vlastnosti těchto automatů, jejich vztah k Chomskeho hierarchii a možnosti učení těchto automatů na základě pozitivních a negativních příkladů.Restarting automata were introduced as a model for analysis by reduction which is a linguistically motivated method for checking correctness of a sentence. The goal of the thesis is to study more restricted models of restarting automata which based on a limited context can either delete a substring of the current content of its tape or replace a substring by a special symbol, which cannot be overwritten anymore, but it can be deleted later. Such restarting automata are called clearing restarting automata. The thesis investigates the properties of clearing restarting automata, their relation to Chomsky hierarchy and possibilities for machine learning of such automata from positive and negative samples.Department of Software and Computer Science EducationKatedra softwaru a výuky informatikyFaculty of Mathematics and PhysicsMatematicko-fyzikální fakult

Deterministic Receptive Processes are Kahn Processes

Deterministic asynchronous concurrent formalisms are valuable because determinism greatly simplifies the design and validation of such systems and most concurrent formalisms are nondeterministic. This paper connects two of the more successful deterministic asynchronous formalisms: Kahn's dataflow networks and Josephs's deterministic receptive processes. The main result: a divergence-free deterministic receptive process is a Kahn process in that it can be modeled by a continuous function from input to output sequences, thus verifying it is compositionally deterministic. This result provides a bridge between two communities, enabling results from the asynchronous digital hardware community to be used in the context of dataflow computation and vice versa

Parity and Streett Games with Costs

We consider two-player games played on finite graphs equipped with costs on edges and introduce two winning conditions, cost-parity and cost-Streett, which require bounds on the cost between requests and their responses. Both conditions generalize the corresponding classical omega-regular conditions and the corresponding finitary conditions. For parity games with costs we show that the first player has positional winning strategies and that determining the winner lies in NP and coNP. For Streett games with costs we show that the first player has finite-state winning strategies and that determining the winner is EXPTIME-complete. The second player might need infinite memory in both games. Both types of games with costs can be solved by solving linearly many instances of their classical variants.Comment: A preliminary version of this work appeared in FSTTCS 2012 under the name "Cost-parity and Cost-Streett Games". The research leading to these results has received funding from the European Union's Seventh Framework Programme (FP7/2007-2013) under grant agreements 259454 (GALE) and 239850 (SOSNA