The following papers describe how CP-nets and the CPN tools were used to design and validate a security system and an access control system. For the access control system the implementation was done by a fully automatic extraction of the CPN code used in the CPN simulator.
The first of the two projects is also described in Chapter 1 of:
This paper presents a model-based approach to requirements engineering for reactive systems, and more specifically to controllers. The approach suggests the creation of a CPN model based on several diagrams, for validating the functional requirements of the system under development. The paper proposes a generic structure for the CPN model to address the modelling of the controller, the physical entities which the controller interacts with, and the human users that operate the system. The CPN modules for modelling the behaviour of the human users and the controller are instances of a generic module that is able to interpret scenario descriptions specified in CPN ML.
The following paper deals with the modelling and analysis of a simple mechatronic, hybrid system at the research laboratories of Peugeot-Citroën, France. The long term goal of this line of research is to be able to use CP-nets for dependability analysis of car systems, such as automatic gear boxes, active suspensions, and ABS brakes. The kind of problems encountered during this project is typical for the area of rare events simulation. The paper presents three different models. The first CPN model is easy to understand and close to the concepts used by the designers of the system. It updates the system state with very short intervals, calculating the new values of the system variables from the old ones by means of a set of mathematical formulas describing the physical properties of the continuous parts of the hybrid system. The second CPN model is much more abstract. It describes the system state by specifying a start situation and the way in which the state is progressing. This means that it is sufficient to recalculate the state when certain discrete events occur, e.g., when a certain threshold is reached. Hence, the simulations become much more efficient. The third model is a stand-alone program in the functional language Standard ML. It is a recursive function obtained from the abstract CPN model in a semi-automatic way by reusing the data structures and the functions in the CPN model. All three models were investigated by means of lengthy simulations. Moreover, state spaces were used to investigate the different ways in which failures can lead to feared events.
The following paper describes how CP-nets and the CPN tools were used to model parts of the new European train control system. The work was done at the Institute for Control and Automation Engineering at the Technical University of Braunschweig, Germany within a project for the German railways.
The following paper describes how CP-nets and the CPN tools have been used to model the communication mechanisms used in a flowmeter system produced by Danfoss, which is one of the largest Danish industrial companies.
The following paper describes how CP-nets and the CPN tools were used to design and visualise the behaviour of a traffic control systems.
The following paper presents a method for the description and validation of control procedures for multipurpose chemical batch plants (which in many respects are similar to flexible manufacturing systems). The method is based on the use of recipes, which is a standardised concept used by the big chemical companies. The recipes and plant description are transformed into CP-nets, which are investigated by simulation and by state space analysis to find desired or critical behaviour, e.g., resource conflicts and deadlocks.
The project is also described in Chapter 18 of:
The following paper describes the design of a CPN model for a rather complex model train system. The purpose is to teach graduate computer science students net modelling and analysis techniques, and the systematic conversion of non-trivial net models into fully operational real systems.
The following papers describes a teaching experience with a group of twenty graduate students, during their second year in engineer school. The purpose is to teach the application of specification and validation techniques in a control system for a model railway. Design/CPN is one of the tools used by the students.
The following paper describes how CPN can be used to enhance a traditional software specifications document for an elevator controller. Based on the given specification a CPN model is built, which is a coherent description that ties together different pieces of the given specification. The CPN model is used to argue for the correctness of the specification. Using simulation, a number of scenarios are investigated. For each scenario, it is checked that if a controller is implemented in compliance with the specification, it will ensure the desired effects in the subject domain.
