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To address issues such as inadequate fault tolerance, long computation time, and limited universality in fault location for active distribution networks, this paper proposes a fault location method that combines Petri nets with an improved particle swarm optimization (PSO) algorithm. This method enhances the efficiency of fault location in distribution networks with distributed power sources, demonstrating good applicability and convergence, especially in complex network scenarios. The results from two test functions and simulation analyses of two types of node distribution networks show that (1) in the single-point fault simulation, the improved algorithm successfully located the fault in the ninth iteration, outperforming the 14th iteration result of the standard PSO algorithm. (2) In networks with randomly interconnected distributed power sources, the algorithm accurately located both single and multiple faults. (3) Experimental verification further supports the simulation results, proving the effectiveness of this method in practical applications. [ABSTRACT FROM AUTHOR]

This paper introduces a virtual consensus‐based wide area differential protection method through cooperative control concepts and graph theory. Using multi‐agent systems eliminates the need for a direct telecommunication connection between the protective relays to implement the proposed differential protection. In addition, applying telecommunication subgraphs facilitates the establishment of numerous differential protection areas. Collaboration between protected areas is facilitated by common agents, establishing a wide‐area cooperative protection network. The capability of the network operator to define various protection areas and the collaboration between these areas ensure the versatility of the proposed method for various protection purposes. The present paper primarily represents the application of the proposed protection system as a wide‐area supervisor protection for distance relays. Performance evaluations on an IEEE 39‐bus test system illustrate the method's effectiveness in various scenarios. The results show enhanced power system stability and resilience, particularly when traditional methods struggle to detect power swings with high impedance variation rates. [ABSTRACT FROM AUTHOR]

Previous research investigating relations between general intelligence and graph-theoretical properties of the brain's intrinsic functional network has yielded contradictory results. A promising approach to tackle such mixed findings is multi-center analysis. For this study, we analyzed data from four independent data sets (total N > 2000) to identify robust associations amongst samples between g factor scores and global as well as node-specific graph metrics. On the global level, g showed no significant associations with global efficiency or small-world propensity in any sample, but significant positive associations with global clustering coefficient in two samples. On the node-specific level, elastic-net regressions for nodal efficiency and local clustering yielded no brain areas that exhibited consistent associations amongst data sets. Using the areas identified via elastic-net regression in one sample to predict g in other samples was not successful for local clustering and only led to one significant, one-way prediction across data sets for nodal efficiency. Thus, using conventional graph theoretical measures based on resting-state imaging did not result in replicable associations between functional connectivity and general intelligence. [ABSTRACT FROM AUTHOR]

The reconfiguration framework models the concept of transformation of combinatorial objects under a variety of operations and constraints. When it comes to reconfiguration challenges, the questions of importance are connectivity, diameter and distance, which can be considered and restrained in many ways. This work focuses on the Token Swap problem, a reconfiguration problem with variations that even precede the systematic study of the reconfiguration framework. In this problem, the goal is to convert an initial token placement on the vertices of a graph into a target token placement with the minimum number of swap operations. The main result of this paper is the construction of a polynomial algorithm for threshold graphs and subsequently cographs. [ABSTRACT FROM AUTHOR]

Tether-nets are one of the most promising approaches for active removal of space debris. This paper investigated the collision dynamics of flexible nets with different configurations, the focus is on the selection of an optimal configuration with respect to collision dynamics. Firstly, the design method of net configuration is proposed based on undirected graph theory, and five flexible nets with different configurations are designed, including quadrilateral, pentagon, octagon, dodecagon and circle. Secondly, the collision dynamics model is presented and its effectiveness is verified via numerical simulations and ground experiments. Finally, collision dynamics of the five flexible nets are simulated based on the verified model and the differences of these nets are compared and analyzed. Comparison results show that the flexible net with octagon configuration has better collision dynamics than others according to the maximum deformation, stress, and energy dissipation during the collision process, which provided an optimal configuration of flexible nets for space debris removal. • A design method of net configuration based on undirected graph is proposed. • The collision dynamics model of flexible nets is proposed and verified. • The octagonal net has the best dynamic characteristics. [ABSTRACT FROM AUTHOR]

Certificates are integral to the security of today's Internet. Protocols like BlockVoke allow secure, timely and efficient revocation of certificates that need to be invalidated. ACME, a scheme used by the non-profit Let's Encrypt Certificate Authority to handle most parts of the certificate lifecycle, allows automatic and seamless certificate issuance. In this work, we bring together both protocols by describing and formalizing an extension of the ACME protocol to support BlockVoke, combining the benefits of ACME's certificate lifecycle management and BlockVoke's timely and secure revocations. We then formally verify this extension through formal methods such as Colored Petri Nets (CPNs) and conduct a risk and threat analysis of the ACME/BlockVoke extension using the ISSRM domain model. Identified risks and threats are mitigated to secure our novel extension. Furthermore, a proof-of-concept implementation of the ACME/BlockVoke extension is provided, bridging the gap towards deployment in the real world. [ABSTRACT FROM AUTHOR]

This paper studies the verification and enforcement of deadlock-freeness and liveness in partially controllable Petri nets. First, we introduce a particular type of basis reachability graphs called conflict-free-control-explicit basis reachability graphs (CFCE-BRGs), in which the firings of all structurally conflicting transitions and all controllable ones are explicitly encoded. We propose two sufficient and necessary conditions for verifying deadlock-freeness and liveness of a Petri net; both can be verified by inspecting a CFCE-BRG using graph theory. Moreover, we develop two maximally permissive deadlock-freeness and liveness enforcing supervisors based on the trimming of CFCE-BRGs. The developed approaches are applicable to arbitrary bounded Petri nets, without an exhaustive reachability space enumeration. [ABSTRACT FROM AUTHOR]

Temporal networks and network-structured systems are gaining ground in daily life. Such net-works are Vehicular Ad-hoc NETworks (VANET) and Mobile Ad-hoc NETworks (MANET), in fact, Industry 4.0 requires similar local networks. During mathematical model-based analysis of real temporal systems, it is vital to determine the existence and frequency of accessibility between components. Graph theory is a well-known mathematical tool used for studying accessibility of network components. In previous publications, the author proposed an easy-usable algorithm for determining the existence of interconnection between system-components. The Monte-Carlo Simulation can model the temporality of systems. The aim of this paper is to propose a Monte-Carlo Simulation-based method that estimates symmetry or asymmetry and the frequency of accessibilities between the components of temporal network-structured systems. [ABSTRACT FROM AUTHOR]

To reveal the influence on system performance by the logistic model of reconfigurable manufacturing system (RMS), the generalised stochastic Petri nets (GSPN) modular modelling approach is presented in this paper. It is based upon the characteristics of a bottleneck service. According to this approach, the bottleneck service in the production process is found first. By corresponding different resources in the service to different modules of the GSPN, the module is reconfigured. The analysis of the model using the Markov chain is hereby presented, as is the average utilisation factor of RMS. Following this, the production capacity of different products and the average productivity of reconfigurable manufacturing cells (RMCs) are discussed. [ABSTRACT FROM PUBLISHER]

Deadlock prevention can be achieved by configuring proper initial markings to obtain a live Petri net model. For a class of Petri nets called finite-capacity Systems of Simple Sequential Processes with Resources (S3PR), an algorithm is proposed to find the minimal initial markings of resource places ensuring its liveness. First, conditions on initial markings of resource places are computed under which the strict minimal siphons (SMS) can never be emptied. Then, the minimal initial markings of resource places are computed to ensure liveness of the net. By the proposed algorithm, a live net can be obtained without changing the structure of the original model. The main practical implication of our work is that it can lower the facility cost. A simple example is used to illustrate the application of the algorithm. [ABSTRACT FROM AUTHOR]

This paper develops a deadlock prevention policy for a class of Petri nets that can model flexible manufacturing systems with assembly and disassembly operations. Siphons in a plant Petri net model are divided into elementary and dependent siphons according to the linear dependency of their characteristic T-vectors. The proposed approach is to make every siphon satisfy the controlled-siphon property (the cs-property), i.e., at any reachable marking, any siphon is max-marked, so that no deadlock states can be reached. The satisfiability of the cs-property is achieved by explicitly adding a monitor for each elementary siphon. The max-controllability of a dependent siphon is ensured by properly supervising its elementary siphons. More permissive behaviour of the non-blocking supervisor is obtained through the rearrangement of the output arcs of the monitors. Compared with existing policies reported in the literature, the advantage of the present method is that a small number of monitors are added and the iterative computing process is accordingly avoided. Finally, the application of the proposed method to an FMS example is presented. [ABSTRACT FROM AUTHOR]

In this paper, we propose a Lagrangian relaxation method for solving routing problems for multiple AGVs by decomposition of timed Petri nets. The AGV routing problem is represented by an optimal transition firing sequence problem for timed Petri nets. The timed Petri net is decomposed into several subnets in which the subproblem for each subnet can be easily solved by Dijkstra's algorithm. We show that each subproblem generated by each subnet is polynomially solvable. The optimality of the solution can be evaluated by the duality gap derived by the Lagrangian relaxation method. The performance of the proposed method is compared with a conventional optimisation algorithm with the penalty function method. The effectiveness of the proposed method is demonstrated. [ABSTRACT FROM AUTHOR]

This paper deals with the study of the behaviour of a large class of Petri net: weighted T-systems (WTS). We recall recent results which propose to linearize WTS on a marked graph (MG), in order to obtain a model which can be analysed using tropical algebra like (max,+) or (min,+). In the last part, we present a transformation to extend the previous results. The idea is to introduce synchronization in the model; this kind of transition enriches the model and gives the opportunity to apply the different results. [ABSTRACT FROM AUTHOR]

This paper addresses the deadlock avoidance problem in track systems in semiconductor fabrication. For the system without buffer space in it, the existing deadlock avoidance policies tend to be too conservative. Routing flexibility provides a chance to develop better ones, but makes their computation more complex. This paper models a track system using coloured resource-oriented Petri net (CROPN). Based on the model, a sufficient condition for deadlock-free operation and the corresponding control law are presented. This proposed policy is shown computationally efficient and less conservative than existing methods. An example is presented to demonstrate its application. [ABSTRACT FROM AUTHOR]

In this paper we use First-Order Hybrid Petri nets (FOHPN), an hybrid model that combines fluid and discrete event dynamics, to model the concurrent activities of manufacturing systems. In particular we consider an existing mineral water bottling plant and we show how the FOHPN model is extremely suited to describe the high-throughput production lines, that are one of the main components in the considered plant. Some variations with respect to the previous definition of the FOHPN model are also introduced here to better describe the behavior of the conveyor lines. Finally, we show that, thanks to the fluid approximation of some discrete-event dynamics, the considered plant may also be efficiently simulated using FOHPN. This also enabled us to identify, among the most commonly used configurations of the plant, which are the optimal working conditions in terms of maximal throughput and net profit. [ABSTRACT FROM AUTHOR]

In addition to the graphic-editing facilities, the software tool Tina proposes the construction of a number of representations for the behaviour of Petri nets or Time Petri nets. Various techniques are used to extract views of the behaviour of nets, preserving certain classes of properties of their state spaces. For Petri nets, these abstractions help prevent combinatorial explosion, relying on so-called partial order techniques such as covering steps and/or persistent sets. For Time Petri nets, which have, in general, infinite state spaces, they provide a finite symbolic representation of their behaviour in terms of state classes. [ABSTRACT FROM AUTHOR]

Because of competitiveness, the problem of product and production system developments is becoming increasingly current. From the point of view of products and production systems, companies must have tools to redesign, analyse, choose and manage their developments. After analysing which tools and methods exist in the scientific literature, we present in this paper a general method for assessing the impact of product development on the company. This method can be applied for each criterion that the company wants to analyse (delay, cost, organization, resources, quality, etc); we choose here the delay criterion. The method features four steps. The first step aims to characterize the case study by representing it with generic parameters. The second step offers the construction of a matrix model (called a static model) in order to categorize the product developments. The third step proposes the construction of a Temporized Coloured Petri Net model (called a dynamic model) and the fourth step simulates this model in order to obtain the expected result: the assessment of impact of the product development. At the end of the paper, we propose a case study on a roller tapered bearing manufacturer--the Timken company. [ABSTRACT FROM AUTHOR]

The generation of a set of optimal or near-optimal disassembly sequences is an important task associated with the study of disassembly planning. This task encapsulates actions at the required disassembly depth to reach maximum net revenue while satisfying economic constraints. The Petri net modelling, combined with heuristic search procedures developed in this study, offers an efficient procedure for disassembly sequence generation. The heuristic generates and searches a partial reachability graph to arrive at an optimal or near-optimal disassembly sequence based on the firing sequence of transitions of the Petri net model. The proposed methodology reduces the search space in two areas: (1) pruning the disassembly tree (DT) and, (2) selective tracking of the reachability graph. The efficacy of the proposed methodology is demonstrated by using two examples from the literature. [ABSTRACT FROM AUTHOR]

In Petri nets (PN), because all the input places of a transition are connected to each other with Logical AND to enable the transition, Logical OR connections amongst its input places cannot be modelled. In the case there are k alternatives (Logical ORs) to perform a task, e.g. assembly of a product, k transitions are required for modelling these k alternatives in a PN model, each transition representing each alternative. This inflates the number of transitions in the PN when the number of alternatives increases. This paper introduces CARPN to model the same k alternatives with fewer transitions and places. The similarities between PN and CARPN are discussed, and based on these similarities formal analysis methods are introduced, as well as a new type of graphical representation. Because the elements of the incidence matrix of a CARPN are integers, the current techniques to obtain the invariants of PN can also be applied to CARPN. In the case of systems having similar structures, the reduction of the incidence matrix, keeping its elements integers, is also discussed. [ABSTRACT FROM AUTHOR]

One of the difficulties in modelling dynamic production systems is the representation of changes to the system along time. Coloured Petri nets with changeable structure (CPN-CS) are capable of modelling systems subject to change. However, this is restricted to functionality modelling of the system. In this paper, we extend CPN-CSs into temporized CPN-CS (TCPN-CS). The extension is carried out by associating relevant modelling elements with time parameters and modifying the mechanism for structure change of the CPN-CS model. TCPN-CS makes it possible to model a dynamic production system considering both functionality and performance. A case study is provided to show that TCPN-CS is effective for modelling dynamic production systems. [ABSTRACT FROM AUTHOR]

To understand long‐term ecosystem dynamics, several concepts have been recently proposed that consider 'basins of attraction' to express resilience and 'tipping points' that express sharp change in an ecosystem's behaviour. However, these temporal features remain difficult to identify and quantify because current models usually focus only on a part of the whole ecosystem behaviour, whereas a holistic approach should be preferred.We propose an original family of models based on discrete systems and designed to comprehensively characterize ecosystem dynamics holistically and over the long term. We developed a qualitative model based on Petri nets, made up of a relational graph (interaction network) that was then rigorously handled using transition rules. Unlike traditional modelling and graph theory approaches, transition rules can strongly modify the graph structure (i.e. a dynamic topology occurs).We examined the value of Petri nets when applied to the simple ecosystem of a termite colony. A termite colony comprises of abiotic and biotic components and processes that we explored along all of their possible trajectories.Several temporal features, such as basins of attraction (i.e. strongly connected states), tipping points (critical transitions along trajectories) and various kinds of collapses (functioning systems whose structures were nevertheless fixed), were easily detected and quantified. We propose that Petri nets developed for more complex ecosystems will provide original insights into their holistic behaviour. [ABSTRACT FROM AUTHOR]

Highlights • Full automated PN generation taking as input a topology diagram as used in industry. • Direct transformation of a UML AD of a system/process to the corresponding PN. • Handling and efficiently modelling systems/processes with dependencies and loops. • Providing generic applicability, without targeting specific domains. [ABSTRACT FROM AUTHOR]

Highlights • A parameterized SILs verification approach is proposed on baseline of IEC61508. • Fully correctness proving is done by implementing and comparing with IEC61508-6. • Parametric features facilitate model reuse in large-scale, complex systems. • PFH relies on the balance between CCF and the number of the redundancy channels. • Systems with static components can be simulated by this approach. Abstract The paper proposed an approach of verifying the Safety Integrity Level (SIL) for the high demand safety system. This approach is based on the Stochastic Petri Nets models and Monte Carlo simulation (SPN-MC) and follows the requirements of IEC61508, which is a commonly accepted standard in the domain of functional safety of programmable electronic and control engineering systems. The paper provides a comparative analysis of the SIL with the application of SPN-MC and the Reliability Block Diagram (RBD) method given by EN61508 to prove the correctness and feasibility of the SPN-MC approach. Additionally, a typical large scaled complex system was adopted to apply the novel approach, which is hard for classical analytical methods. [ABSTRACT FROM AUTHOR]

Chemical reaction networks (CRNs) model the behavior of chemical reactions in well-mixed solutions and they can be designed to perform computations. In this tutorial we give an overview of various computational models for CRNs. Moreover, we discuss a method to implement arbitrary (abstract) CRNs in a test tube using DNA. Finally, we discuss relationships between CRNs and other models of computation. [ABSTRACT FROM AUTHOR]

Highlights • The model has incorporated self-concurrent transitions, which has simplified the model, removing many parallel subnets that were performing the same function previously. • Instead of using instantaneous transitions with small delays to settle firing disputes, instantaneous transitions with priority parameters are used instead. • Stocking was moved to a primary task, able to be completed by all staff, rather than only by pharmacists, which mirrors real practice more closely. • After the model was updated with these improvements, simulations were re-run and new results generated for all tables and figures. • Further explanation of the modelling technique, theory on Petri nets, derivation of results, and more, have been included at various points within the paper, to address oversights pointed out by reviewers. Abstract It has been estimated that European customers visit community pharmacies to access essential primary healthcare around 46 million times every day. Studies of dispensing error rates in community pharmacies have reported error rates of between 0.08% and 3.3% per item dispensed. While severe cases of dispensing inaccuracies often garner a high level of media coverage, less significant errors are also causing inefficiencies in primary healthcare delivery. If a variety of dispensing protocols and their consequences could be analysed using a modelling tool, the results would form the evidence for decisions on best practice guidelines in order to improve patient safety and pharmacy efficiency. This paper presents a Coloured Petri Net (CPN) modelling technique for analysing the reliability and efficiency of a community pharmacy dispensing process. The proposed approach is a novel method for considering reliability and efficiency in a single simulation based model. The CPN model represents how a team of practitioners work together to complete a set of tasks carried out in community pharmacies. It describes a close-to-reality dispensing process, which evaluates pharmacy performance over a number of key performance indicators of process reliability and efficiency, and records how staff distribute their time between tasks. Where possible, results are validated against published studies of community pharmacies. [ABSTRACT FROM AUTHOR]

This paper deals with the identification problem of faulty behavior in a discrete event system, assuming that the fault-free model of a system is given in terms of Petri nets, where the set of transitions is divided into two disjoint subsets: 1) observable and 2) unobservable ones. The observed system output is defined as a transition-marking sequence, i.e., each transition is followed by a marking. First, a nonlinear integer programming model that characterizes the faults modeled by fault transitions is built according to the abnormal behavior extracted from the observed sequence. Then, it is converted into an integer linear programming (ILP) problem and a faulty net that preserves the structure of the fault-free one is obtained by solving this ILP model. In addition, an algorithm is developed to ensure acyclicity of the resulting unobservable subnet whose transition set is composed of the unobservable transitions of the fault-free net and the identified fault transitions. [ABSTRACT FROM AUTHOR]

We present a novel framework called geoexpression for representing geographic process concurrency and discuss its implications for geographic dynamic modeling. Unapt representations of geographic process concurrency can lead to non‐deterministic geographic dynamic modeling outcomes, excessive cognitive burdens when reasoning about how concurrent processes interact, and even inconsistent results. After demonstrating the importance of geographic process concurrency, we examine how the characteristics of geographic process concurrency are missing from other state‐of‐the‐art geographic process representations. The geoexpression framework adopts Petri networks to allow researchers to understand how to relate geographic process concurrency to observed modeling patterns. Of interest are the real‐world geographic patterns formed by concurrent geographic processes. [ABSTRACT FROM AUTHOR]

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A loading problem in a modern FMS is the allocation of a job from the job pool maintaining the flexibility of the system, reducing the system imbalance and thereby maximizing the throughput. In this context a heuristic has been developed. Ten sample problems have been tested with the proposed heuristic. A comparison has been made with the existing methods and it is found that the results are encouraging and indicate significant improvement. The Petri net model for the problem attempted by the proposed heuristic has been constructed to delineate its graphical representation and subsequent validation. [ABSTRACT FROM AUTHOR]

In this paper we propose Management Petri Nets (MPN), an extension of classical Petri nets for modelling management systems. MPN have three kinds of places: status places, resource places and information places, and two kinds of transitions: AND transitions and XOR transitions. A hierarchical approach is utilized in the modelling of management systems with MPN. The integration of MPN models with the Information Technology support of management tasks through a common database is also proposed. [ABSTRACT FROM AUTHOR]

This paper shows Petri nets (PNs) as a powerful tool to investigate the problem often encountered in manufacturing systems management, namely comparing the performance of a flexible factory automated system (FFAS) operating under push and pull paradigms. The difficulty in solving this type of problems is compounded by many parameters such as processing times at work cells, number of automated guided vehicles and their routeings, lot sizes, and setup times. The PN method to solve such a problem is illustrated by considering an FFAS. Its PN models are formulated and then analysed to compare the performance of FFAS with 'push and 'pull' paradigms. The results show that for the particular FFAS and operational parameters. the 'push' paradigm outperforms the 'pull' one. It is concluded that PNs are a suitable tool to conduct performance analysis before adopting the 'push' or 'pull' paradigm. [ABSTRACT FROM AUTHOR]

Three graphical method families are investigated and compared in terms of their representability in production control problems. The confrontation put PERT networks and their extensions in GANs before the same comparison basis as Petri nets and the neat GRAI nets suggested by one of the authors. [ABSTRACT FROM AUTHOR]

Abstract The verification of safety properties for concurrent systems often reduces to the coverability problem for Petri nets. This problem was shown to be ExpSpace -complete forty years ago. Driven by the concurrency revolution, it has regained a lot of interest over the last decade. In this paper, we propose a generic and simple approach to solve this problem. Our method is inspired from the recent approach of Blondin, Finkel, Haase and Haddad presented at TACAS in 2016. Basically, we combine forward invariant generation techniques for Petri nets with backward reachability for well-structured transition systems. An experimental evaluation demonstrates the efficiency of our approach. [ABSTRACT FROM AUTHOR]

Abstract This paper describes two results within the context of Petri net synthesis from labelled transition systems. We consider a set of structural properties of transition systems, and we show that, given such properties, it is possible to re-engineer a Petri net realisation into one which lies inside the set of marked graphs, a well-understood and useful class of Petri nets. The first result originates from Petri net based workflow specifications, where it is desirable that k customers can share a system without mutual interferences. In a Petri net representation of a workflow, the presence of k customers can be modelled by an initial k -marking, in which the number of tokens on each place is a multiple of k. For any initial k -marking with k ≥ 2 , we show that other desirable assumptions such as reversibility and persistence suffice to guarantee marked graph realisability. For the case that k = 1 , we show that the existence of certain cycles, along with other properties such as reversibility and persistence, again suffices to guarantee marked graph realisability. [ABSTRACT FROM AUTHOR]

As information technology advances dramatically and the stock market in Taiwan turns out to be active, the management of financial investment has already become very important. To facilitate the rapid development of the stock market, the application of information technology to financial investment becomes a hot issue. In this paper, a support vector regression (SVR) machine for stock prices in Taiwan is adopted to simulate the approximate trading trend by using the daily data sets. Then the learned data model is used to analyze technical indices, to draw a trend diagram, and to make a prediction. Finally, the business behavior of financial investment systems has been modeled by using a high-level fuzzy Petri net (HLFPN) for the purpose of making a decision on appropriate investment. Based on the HLFPN model, the proposed approach provides each investor with relevant information to understand the investment trend. As a result, a practical market stock prediction system is presented to enhance the investment benefits and help investors achieve the desired investment goal. [ABSTRACT FROM AUTHOR]

This paper presents a modeling method by stochastic Petri net for reliability analysis of phased mission system (PMS) with phase backup. The model consisting of petri nets, depicts the system behaviors of unit level, system logic level and phase level. Guard functions of petri nets are used to avoid modeling complexity and make the model flexible to different reliability logical structures. It was shown that the time redundancy within phase and from phase backup for PMS can both be described by use of the proposed model. [ABSTRACT FROM AUTHOR]

Systems-Theoretic Accident Modeling and Process (STAMP) is a novel accident causality model and has been used in various areas. Most of the STAMP based hazard analysis methods are ad-hoc without rigorous procedures, and the process model used in STAMP is too simple to identify the hazardous control actions as the causes. Petri nets, which have been used to graphically model computer-controlled systems and resolve system safety issues, can make the hazard analysis with STAMP more effective. To identify the hazardous control actions in the STAMP-based hazard analysis, extended Petri nets are proposed in this paper to model the control processes in the system control structure. The runtime control action failures are considered in the reachability graph for the hazard analysis. Furthermore, the types of hazardous control actions are studied and analyzed in the extended reachability graph. [ABSTRACT FROM AUTHOR]

Systems Biology Graphical Notation (SBGN) is a standard graphical language for representing biological and biochemical processes and interactions. Even that SBGN Process Description-an SBGN sub-language-facilitates biological systems representation, it allows only qualitative descriptions of metabolic pathways and does not provide quantitative analytic environment. However such descriptions are essential for behavioural analysis. This analysis can be possible using computational formalisms such as Hybrid Functional Petri Net (HFPN) which is a Petri net extension dedicated to study and verify biopathways. However, biologists use generally graphical notations such as SBGN. To address this paradox, we propose, in this paper, an SBGN-PD to HFPN transformation based on Model Driven Engineering (MDE). Furthermore, we illustrate this transformation on the Glycolysis pathway and verify the transformation resulting HFPN model by comparing it with the existing HFPN model through simulation. [ABSTRACT FROM AUTHOR]

Time Petri nets (TPNs) have been widely used for modeling discrete event systems such as manufacturing, supply chain, and military systems. However, TPNs still have many drawbacks in some scenarios where an operation or process is associated with probability, and also lack appropriate simulation algorithms for analyzing different types of systems. In this paper, we address these two issues by proposing a class of extended time Petri nets (ETPNs) and presenting an appropriate simulation algorithm. We illustrate and validate our approach using a hypothetic command and control system, which shows that this approach could be a powerful tool for modeling and analyzing discrete event systems. [ABSTRACT FROM AUTHOR]

Petri net synthesis deals with the problem whether, given a labelled transition system TS, one can find a Petri net N with an initial marking M0 such that the reachability graph of (N;M0) is isomorphic to TS. This may be preceded by a pre-synthesis phase that will quickly reject ill-formed transition systems (and give structural reasons for the failure) and otherwise build data structures needed by the proper synthesis. The last phase proceeds by solving systems of linear inequalities, and may still fail but for less transparent reasons. In this paper, we consider an extended problem. A finite set of transition systems {TS1,....,TSm} shall be called simultaneously Petri net solvable if there is a single Petri net N with several initial markings {M01,....,M0m}, such that for every i = 1,....,m, the reachability graph of (N;M0i) is isomorphic to TSi. The focus will be on choice-free nets, that is, nets without structural choices, and we explore how previously published eficient algorithms for the pre-synthesis and proper synthesis of bounded and choice-free Petri nets can be generalised for the simultaneous pre-synthesis and synthesis of such multi-marked nets. At the same time, the choice-free pre-synthesis of a single transition system shall be strengthened by introducing new structural checks. [ABSTRACT FROM AUTHOR]

It is well-known that the reachability graph of a sum of disjoint Petri nets is the disjoint product of the reachability graphs of the components. We shall consider here the converse problem, i.e., determine when and how a transition system may be decomposed in non-trivial concurrent factors, and extend the theory to more general labelled transition systems. Meanwhile, we shall develop interesting algebraic properties of disjoint products. The present paper is an extended version of Devillers (in: Desel, Yakovlev (eds) Proceedings 16th international conference on application of concurrency to system design (ACSD 2016), 2016). [ABSTRACT FROM AUTHOR]

Interval semantics of elementary Petri nets with inhibitor arcs is discussed. First an operational semantics in terms of interval orders is provided, and next the concept of interval process is introduced, discussed, and used to describe concurrent histories of such nets. It is shown that the interval process semantics is equivalent to recently proposed interval traces semantics. It is also proven that if operational semantics is restricted to stratified orders (i.e. step sequences) the proposed model is equivalent to models based on step processes and comtraces. [ABSTRACT FROM AUTHOR]