Design of crystal-like lattices can be achieved by using some net operations. Hypothetical networks, thus obtained, can be characterized in their topology by various counting polynomials and topological indices derived from them. The networks herein presented are related to the Dyck graph and described in terms of Omega polynomial and PIv polynomials.

Cleaning pipeline networks is a routine operation in almost every chemical plant. Our aim is to develop a systematic strategy to generate the needed operating procedures with Petri-net models. Specifically, the proper materialtransfer routes are selected on the basis of the Petri-net representation of all possible paths. The equipment models are then attached to this path model according to net...

We present a Petri net model of a protocol for the distributed generation of id-based private keys. Those keys can then be used for secure communications. The components of the system are built as refinements of a common interface, by applying a formal operation based on a class of morphisms between Elementary Net Systems. It is then shown that we can derive behavioural properties of the compos...

In a seminal paper Montanari and Meseguer showed that an algebraic interpretation of Petri nets in terms of commutative monoids can be used to provide an elegant characterisation of the deterministic computations of a net, accounting for their sequential and parallel composition. Here we show that, along the same lines, by adding an (idempotent) operation and thus taking dioids (commutative sem...

To address some questions of usage of European airspace by United States Air Force aircraft, two simulation models are employed. The first model offers a wide array of functions to represent aircraft movement and management of aggregates or "flows" of aircraft. The second model uses a Petri net approach to represent the complexity of a flight planning/replanning operation, in order to estimate ...

Recent advances in Internet and e-commerce have led industry to reengineer their organizational structures and value chains. One of the most prominent trends in this change is to conduct work and operation in the distributed or virtual environments. A new kind of business model, termed as value-net, is emerging. In this paper, the business and system mode from the value-net system is studied an...

An ant colony algorithm is proposed to improve the net present values of resource-constrained projects since the net present value is a critical criterion for a project with a long time span and considerable cash flows. The algorithm adaptively adjusts the allocation of scarce resources according to the pheromone generated by artificial ants in the previous iterations so as to maximize the proj...