On the Expressivity of Symmetry in Event Structures

We present a non-interleaving model for non deterministic concurrent processes that is based on labelled event structures. We define operators on labelled event structures like parallel composition, nondeterministic combination, choice, prefixing and hiding. These operators correspond to the operations of the “Theory of Communicating Sequential Processes” (TCSP). Infinite processes are defined using the metric approach. The dynamic behaviour of event structures is defined by a transition relation which describes the execution of partially ordered sets of actions, abstracting from internal events.

Download Full-text

Time and Duration in Noninterleaving Concurrency

Fundamenta Informaticae ◽

10.3233/fi-1993-193-410 ◽

1993 ◽

Vol 19 (3-4) ◽

pp. 403-416

Author(s):

David Murphy

Keyword(s):

Partial Order ◽

Independent Interest ◽

Underlying Event ◽

Strict Partial Order ◽

Event Structures ◽

Concurrency Theory ◽

Finite Structures

The purpose of this paper is to present a real-timed concurrency theory in the noninterleaving tradition. The theory is based on the occurrences of actions; each occurrence or event has a start and a finish. Causality is modelled by assigning a strict partial order to these starts and finishes, while timing is modelled by giving them reals. The theory is presented in some detail. All of the traditional notions found in concurrency theories (such as conflict, confusion, liveness, and so on) are found to be expressible. Four notions of causality arise naturally from the model, leading to notions of securing. Three of the notions give rise to underlying event structures, demonstrating that our model generalises Winskel’s. Infinite structures are then analysed: a poset of finite structures is defined and suitably completed to give one containing infinite structures. These infinite structures are characterised as just those arising as limits of finite ones. Our technique here, which relies on the structure of time, is of independent interest.

Download Full-text

Cognitive restructuring in the multilingual mind: language-specific effects on processing efficiency of caused motion events in Cantonese–English–Japanese speakers

Bilingualism Language and Cognition ◽

10.1017/s1366728921000018 ◽

2021 ◽

pp. 1-16

Author(s):

Yi Wang ◽

Li Wei

Keyword(s):

Decision Making ◽

Language Contact ◽

Cognitive Restructuring ◽

Target Language ◽

Decision Making Process ◽

Processing Efficiency ◽

Positive Evidence ◽

Specific Effects ◽

Event Structures ◽

Thinking For Speaking

Abstract The current study explores how multilingual speakers with three typologically different languages (satellite-framed, verb-framed and equipollent-framed) encode and gauge event similarity in the domain of caused motion. Specifically, it addresses whether, and to what extent, the acquisition of an L2-English and an L3-Japanese reconstructs the lexicalization and conceptualization patterns established in the L1-Cantonese when the target language is actively involved in the decision-making process. Results show that multilingual speakers demonstrated an ongoing process of cognitive restructuring towards the target language (L3) in both linguistic encoding (event structures and semantic representations) and non-linguistic conceptualization (reaction time). And the degree of the restructuring is modulated by the amount of language contact with the L2 and L3. The study suggests that learning a language means internalizing a new way of thinking and provides positive evidence for L3-biased cognitive restructuring within the framework of thinking-for-speaking.

Download Full-text

Transition-Systems, Event Structures, and Unfoldings

Information and Computation ◽

10.1006/inco.1995.1062 ◽

1995 ◽

Vol 118 (2) ◽

pp. 191-207 ◽

Cited By ~ 15

Author(s):

M. Nielsen ◽

G. Rozenberg ◽

P.S. Thiagarajan

Keyword(s):

Transition Systems ◽

Event Structures

Download Full-text

A Compositional Semantics for Timed Petri Nets1

Fundamenta Informaticae ◽

10.3233/fi-1990-13203 ◽

1990 ◽

Vol 13 (2) ◽

pp. 141-170

Author(s):

Andrea Maggiolo-Schettini ◽

Józef Winkowski

Keyword(s):

Petri Nets ◽

Compositional Semantics ◽

Timed Petri Nets ◽

Event Structures ◽

Configuration Systems

Timed Petri nets and their behaviours are considered. A concept of a seminet is introduced. which generalizes the concept of a net, and suitable operations on seminets are defined, which allow constructing seminets from atoms corresponding to places and transitions. The behaviours of seminets are given in the form of so called configuration systems, a notion close to labelled event structures. Such behaviours can be combined with the aid of operations corresponding to those on seminets. In particular, the behaviour of a compound seminet can be obtained by combining the behaviours of components.

Download Full-text

A Temporal Logic for Event Structures

Mathematical Logic ◽

10.1007/978-1-4613-0609-2_23 ◽

1990 ◽

pp. 327-338 ◽

Cited By ~ 3

Author(s):

Wojciech Penczek

Keyword(s):

Temporal Logic ◽

Event Structures

Download Full-text

Bisimulation from Open Maps

BRICS Report Series ◽

10.7146/brics.v1i7.21663 ◽

1994 ◽

Vol 1 (7) ◽

Cited By ~ 6

Author(s):

André Joyal ◽

Mogens Nielsen ◽

Glynn Winskel

Keyword(s):

Petri Nets ◽

Parallel Computation ◽

Transition Systems ◽

New Model ◽

Event Structures ◽

Uniform Definition ◽

Refinement Operators ◽

Definition Of ◽

Open Maps

An abstract definition of bisimulation is presented. It enables a uniform definition of bisimulation across a range of different models for parallel computation presented as categories. As examples, transition systems, synchronisation trees, transition systems with independence (an abstraction from Petri nets) and labelled event structures are considered. On transition systems the abstract definition readily specialises to Milner's strong bisimulation. On event structures it explains and leads to a revision of history-preserving bisimulation of Rabinovitch and Traktenbrot, Goltz and van Glabeek. A tie-up with open maps in a (pre)topos, as they appear in the work of Joyal and Moerdijk, brings to light a promising new model, presheaves on categories of pomsets, into which the usual category of labelled event structures embeds fully and faithfully. As an indication of its promise, this new presheaf model has ``refinement'' operators, though further work is required to justify their appropriateness and understand their relation to previous attempts. The general approach yields a logic, generalising Hennessy-Milner logic, which is characteristic for the generalised notion of bisimulation.

Download Full-text