Membrane Systems and Petri Net Synthesis

Automated synthesis from behavioural specifications is an attractive and powerful way of constructing concurrent systems. Here we focus on the problem of synthesising a membrane system from a behavioural specification given in the form of a transition system which specifies the desired state space of the system to be constructed. We demonstrate how a Petri net solution to this problem, based on the notion of region of a transition system, yields a method of automated synthesis of membrane systems from state spaces.Comment: In Proceedings MeCBIC 2012, arXiv:1211.347

Recent advances in petri nets and concurrency

CEUR Workshop Proceeding

Synthesis of Petri Nets with Localities

Automated synthesis from behavioural specifications is an attractive way of constructing computational systems. In this paper, we look at a specific instance of this approach which aims at constructing GALS (globally asynchronous locally synchronous) systems. GALS systems are represented by Petri nets with localities, each locality defining a set of co-located actions, and specifications are given in terms of transition systems with arcs labelled by steps of executed actions. The proposed synthesis procedures are based on the regions of transition systems, and work without knowing which actions are to be co-located. We consider two basic classes of Petri nets, viz. Elementary Net System with Localities (ENL-system) and Place/Transition nets with localities (PTL-nets). In particular, we discuss ENL-systems where there is no conflict between events coming from different localities. In such a case, the synthesis problem reduces to checking just one co-location relation. This result is then extended to PTL-nets

Adding A/Sync Places to the Synthesis Procedure for Whole-Place Operations Nets with Localities

Algorithms and the Foundations of Software technolog

Petri Nets for Biologically Motivated Computing

Petri nets are a general and well-established model of concurrent and distributed computation and behaviour, including that taking place in biological systems. In this survey paper, we are concerned with intrinsic relationships between Petri nets and two formal models inspired by aspects of the functioning of the living cell: membrane systems and reaction systems. In particular, we are interested in the benefits that can result from establishing strong semantical links between Petri nets and membrane systems and reaction systems. We first discuss Petri nets with localities reflecting the compartmentalisation modelled in membrane systems. Then special attention is given to set-nets, a new Petri net model for reaction systems and their qualitative approach to the investigation of the processes carried out by biochemical reactions taking place in the living cell

Nested-unit Petri nets

International audiencePetri nets can express concurrency and nondeterminism but neither locality nor hierarchy. This article presents an extension of Petri nets, in which places can be grouped into so-called "units" expressing sequential components. Units can be recursively nested to reflect both the concurrent and hierarchical nature of complex systems. This model called NUPN (Nested-Unit Petri Nets) was originally developed for translating process calculi to Petri nets, but later found also useful beyond this setting. It allows significant savings in the memory representation of markings for both explicit-state and symbolic verification. Thirteen software tools already implement the NUPN model, which has also been adopted for the benchmarks of the Model Checking Contest (MCC) and the parallel problems of the Rigorous Examination of Reactive Systems (RERS) challenges

Modelling gradients using petri nets

Computer Systems, Imagery and MediaAlgorithms and the Foundations of Software technolog

Signal set tissue systems and overlapping localities

Algorithms and the Foundations of Software technolog

Petri net model decomposition - a model based approach supporting distributed execution

Dissertação apresentada para obtenção do Grau de Doutor em Engenharia Electrotécnica, Especialidade de Sistemas Digitais, pela Universidade Nova de Lisboa, Faculdade de Ciências e TecnologiaModel-based systems development has contributed to reducing the enormous difference between the continuous increase of systems complexity and the improvement of methods and methodologies available to support systems development. The choice of the modeling formalism is an important factor for success-fully increasing productivity. Petri nets proved to be a suitable candidate for being chosen as a system specification language due to their natural support of modeling processes with concurrency, synchronization and resource sharing, as well as the mechanisms of composition and decomposition. Also having a formal representation reinforces the choice, given that the use of verification tools is fundamental for complex systems development. This work proposes a method for partitioning Petri net models into concurrent sub-models, supporting their distributed implementation. The IOPT class (Input-Output Place Transition) is used as a reference class. It is extended by directed synchronous communication channels, enabling the com- munication between the generated sub-models. Three rules are proposed to perform the partition, and restrictions of the proposed partition method are identified. It is possible to directly compose models which result from the partitioning operation, through an operation of model addition. This allows the re-use of previously obtained models, as well as the easy modification of the intended system functionalities. The algorithms associated with the implementation of the partition operation are presented, as well as its rules and other procedures. The proposed methods are validated through several case studies emphasizing control components of automation systems

The development of object oriented Bayesian networks to evaluate the social, economic and environmental impacts of solar PV

Domestic and community low carbon technologies are widely heralded as valuable means for delivering sustainability outcomes in the form of social, economic and environmental (SEE) policy objectives. To accelerate their diffusion they have benefited from a significant number and variety of subsidies worldwide. Considerable aleatory and epistemic uncertainties exist, however, both with regard to their net energy contribution and their SEE impacts. Furthermore the socio-economic contexts themselves exhibit enormous variability, and commensurate uncertainties in their parameterisation. This represents a significant risk for policy makers and technology adopters. This work describes an approach to these problems using Bayesian Network models. These are utilised to integrate extant knowledge from a variety of disciplines to quantify SEE impacts and endogenise uncertainties. A large-scale Object Oriented Bayesian network has been developed to model the specific case of solar photovoltaics (PV) installed on UK domestic roofs. Three specific model components have been developed. The PV component characterises the yield of UK systems, the building energy component characterises the energy consumption of the dwellings and their occupants and a third component characterises the building stock in four English urban communities. Three representative SEE indicators, fuel affordability, carbon emission reduction and discounted cash flow are integrated and used to test the model s ability to yield meaningful outputs in response to varying inputs. The variability in the percentage of the three indicators is highly responsive to the dwellings built form, age and orientation, but is not just due to building and solar physics but also to socio-economic factors. The model can accept observations or evidence in order to create scenarios which facilitate deliberative decision making. The BN methodology contributes to the synthesis of new knowledge from extant knowledge located between disciplines . As well as insights into the impacts of high PV penetration, an epistemic contribution has been made to transdisciplinary building energy modelling which can be replicated with a variety of low carbon interventions