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A net presentation of Lithuanian sentences containing verbal forms with the grammatical suffix -dav-

100%
Roszko D., Roszko R.
Cognitive Studies
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2014
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issue 14
173-182
EN
In the article the authors make an attempt to present the meaning of Lithuanian sentences containing verbal forms with the grammatical suffix -dav- (the so-called iterative past tense forms) by means of Petri nets. The authors gradually develop the net to such complexity that it makes it possible to avoid interpretative similarities to other Lithuanian verbal forms.
2

Logics for Physarum Chips

88%
Schumann A., Pancerz K.
Studia Humana
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2016
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vol. 5
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issue 1
16-30
EN
The paper considers main features of two groups of logics for biological devices, called Physarum Chips, based on the plasmodium. Let us recall that the plasmodium is a single cell with many diploid nuclei. It propagates networks by growing pseudopodia to connect scattered nutrients (pieces of food). As a result, we deal with a kind of computing. The first group of logics for Physarum Chips formalizes the plasmodium behaviour under conditions of nutrient-poor substrate. This group can be defined as standard storage modification machines. The second group of logics for Physarum Chips covers the plasmodium computing under conditions of nutrient-rich substrate. In this case the plasmodium behaves in a massively parallel manner and propagates in all possible directions. The logics of the second group are unconventional and deal with non-well-founded data such as infinite streams.
3
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Control design for untimed Petri nets using Markov Decision Processes

88%
DAOUI C., LEFEBVRE D.
Operations Research and Decisions
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2017
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vol. 27
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issue 4
27-43
EN
Design of control sequences for discrete event systems (DESs) has been presented modelled by untimed Petri nets (PNs). PNs are well-known mathematical and graphical models that are widely used to describe distributed DESs, including choices, synchronizations and parallelisms. The domains of application include, but are not restricted to, manufacturing systems, computer science and transportation networks. We are motivated by the observation that such systems need to plan their production or services. The paper is more particularly concerned with control issues in uncertain environments when unexpected events occur or when control errors disturb the behaviour of the system. To deal with such uncertainties, a new approach based on discrete time Markov decision processes (MDPs) has been proposed that associates the modelling power of PNs with the planning power of MDPs. Finally, the simulation results illustrate the benefit of our method from the computational point of view.
4
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Constructing catalogue of temporal situations

75%
Koseska-Toszewa V., Mazurkiewicz A.
Cognitive Studies
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2010
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issue 10
EN
Constructing catalogue of temporal situationsThe paper is aiming to create a common basis for description, comparing, and analysis natural languages. As a subject of comparison we have chosen temporal structures of some languages. For such a choice there exists a perfect tool, describing basic temporal phenomena, namely an ordering of states and events in time, certainty and uncertainty, independency of histories of separate objects, necessity and possibility. This tool is supported by the Petri nets formalism, which seems to be well suited for expressing the above mentioned phenomena. Petri nets are built form three primitive notions: of states, of events that begin or end the states, and so-called flow relation indicating succession of states and events. This simple constituents give rise to many possibilities of representing temporal phenomena; it turns out that such representations are sufficient for many (clearly, not necessarily all) temporal situations appearing in natural languages.In description formalisms used till now there is no possibility of expressing such reality phenomena as temporal dependencies in compound statement, or combination of temporality and modality. Moreover, using these formalisms one cannot distinguish between two different sources of uncertainty of the speaker while describing the reality: one, due to the lack of knowledge of the speaker what is going on in outside world, the second, due to objective impossibility of foreseen ways in which some conflict situations will be (or already have been) resolved. Petri net formalism seems to be perfectly suited for such differentiations.There are two main description principles that encompassed this paper. First, that assigns meaning to names of grammatical structures in different languages may lead to misunderstanding. Two grammatical structures with apparently close names may describe different reality. Additionally, some grammatical terms used in one language may be absent and not understandable in the other. It leads to assign meanings to situations, rather than to linguistic forms used for their expression. The second principle is limit the discussed issues to such a piece of reality that can be possible for precise description. The third is to avoid introducing such information to the described reality that is not explicitly mentioned by linguistic means. The authors try to following these principles in the present paper.The paper is organized as follows. First, some samples of situations related to present tense are given together with examples of their expressions in four languages: English, (as a reference language) and three Slavic languages, representing South slavonic languages (Bulgarian), West slavonic languages (Polish), and East slavonic languages (Russian). Within the same framework the next parts of the paper are constructed, supplying samples of using Past tenses and, finally, future tenses and modalities.The formal tools for description purposes are introduced stepwise, according to needs caused be the described reality. There are mainly Petri nets, equipped additionally with inscriptions or labeling in order to keep proper assignations of description units to described objects.
5
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Semantics, contrastive linguistics and parallel corpora

75%
Koseska V.
Cognitive Studies
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2014
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issue 14
85-100
EN
In view of the ambiguity of the term “semantics”, the author shows the differences between the traditional lexical semantics and the contemporary semantics in the light of various semantic schools. She examines semantics differently in connection with contrastive studies where the description must necessary go from the meaning towards the linguistic form, whereas in traditional contrastive studies the description proceeded from the form towards the meaning. This requirement regarding theoretical contrastive studies necessitates construction of a semantic interlanguage, rather than only singling out universal semantic categories expressed with various language means. Such studies can be strongly supported by parallel corpora. However, in order to make them useful for linguists in manual and computer translations, as well as in the development of dictionaries, including online ones, we need not only formal, often automatic, annotation of texts, but also semantic annotation - which is unfortunately manual. In the article we focus on semantic annotation concerning time, aspect and quantification of names and predicates in the whole semantic structure of the sentence on the example of the “Polish-Bulgarian-Russian parallel corpus”.
6
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About Certain Semantic Annotation in Parallel Corpora

63%
Koseska-Toszewa V.
Cognitive Studies
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2013
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issue 13
EN
About Certain Semantic Annotation in Parallel CorporaThe semantic notation analyzed in this works is contained in the second stream of semantic theories presented here – in the direct approach semantics. We used this stream in our work on the Bulgarian-Polish Contrastive Grammar. Our semantic notation distinguishes quantificational meanings of names and predicates, and indicates aspectual and temporal meanings of verbs. It relies on logical scope-based quantification and on the contemporary theory of processes, known as “Petri nets”. Thanks to it, we can distinguish precisely between a language form and its contents, e.g. a perfective verb form has two meanings: an event or a sequence of events and states, finally ended with an event. An imperfective verb form also has two meanings: a state or a sequence of states and events, finally ended with a state. In turn, names are quantified universally or existentially when they are “undefined”, and uniquely (using the iota operator) when they are “defined”. A fact worth emphasizing is the possibility of quantifying not only names, but also the predicate, and then quantification concerns time and aspect.  This is a novum in elaborating sentence-level semantics in parallel corpora. For this reason, our semantic notation is manual. We are hoping that it will raise the interest of computer scientists working on automatic methods for processing the given natural languages. Semantic annotation defined like in this work will facilitate contrastive studies of natural languages, and this in turn will verify the results of those studies, and will certainly facilitate human and machine translations.
7
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Definiteness-indefiniteness category and logical quantification

63%
Koseska-Toszewa V.
Cognitive Studies
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2011
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issue 11
EN
Definiteness-indefiniteness category and logical quantificationThis work has been written within the “Logic and Language” project, realized under a cooperation agreement between the Institute of Slavic Studies of the Polish Academy of Sciences and the Institute of Bulgarian Language of the Bulgarian Academy of Sciences. The publication of a many-volume Bulgarian Polish Grammar (12 monographs), and of a Polish-Bulgarian Contrastive Grammar, from now on: Synthesis, is completed. Theories of mathematical logic are satisfied in perfect way in a natural language, which is shown by our understanding of the semantic definiteness / indefiniteness category as a system of scope-based quantification notions. A natural language complements and modifies logical theories. For example, understanding of the definiteness / indefiniteness category as a sentence category follows from the language material, especially in article languages. In such languages, quantification of the predicate is a necessary prerequisite for interpretation. Also introduction of the notions of strong and weak quantification meanings is motivated, for example, by the need to distinguish between the meanings of expressions like Pol. pewien x, jakiś x / Bulg. njakoj x, njakakyv x on the nominal phrase level, and by understanding of the ambiguity of quantification expressions like Bulg. vinagi, ponjakoga / Pol. zawsze, czasami. The fact of treating the definiteness / indefiniteness category as a sentence category expands understanding of the incomplete quantification notion also with respect to the verbal phrase, rather than, as in Ajdukiewicz’s approach, with respect to the nominal phrase only. Similarly, a proper name in a natural language is not a unique name, like in mathematical logic, but requires additional unique quantification. A network-based description of time is the first attempt at this type of description in the subject literature. In the present article, I stress that fact that quantification of states and events understood as in Petri net theory reveals the dependence between the aspectual and temporal meanings of verb, and proves that the information on time and aspect need not be dealt with separately.
8
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Modelowanie i symulacja pracy złożonych systemów technicznych

63%
KĘSY M.
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2015
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vol. 6
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issue 3
225-231
PL
Przedstawiono podstawowe informacje z zakresu modelowania systemów technicznych. Zaprezentowano możliwość modelowania złożonego systemu technicznego za pomocą modelu matematycznego – sieci Petriego, analizując ich praktyczną i dydaktyczną użyteczność.
EN
In the paper basic information regarding modelling of the technical systems has been presented. Modelling of the complex technical system was performed by Petri nets theory. Their professional and didactical useability has been analyzed.
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