Partitioning has always been a challenge in the design of distributed applications. It allows optimizing the intercommunication between the system components and so increasing the lifetime of the network. Graph theory methods have often been used to perform partitioning in classic distributed systems but seem to be not efficient in ad hoc or wireless sensor networks (WSN). The main reason is related to the topology of these kinds of networks and the presence of multihop communication. In this paper, we propose a new self-organisation of the WSN based on the optimization of the number of jumps between any sensor and the sink. The network is based on a two-level hierarchy structure and organised as a set of clusters with one cluster-head by cluster and a super-leader for the entire network. The optimisation process has been performed and validated by introducing some parameters, baptized cohesion parameters. The simulation of our approach compared to existing and previously developed protocols shows the efficiency of the method. The results are very interesting and allow projecting several perspectives to improve performances by using other metrics.

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This paper proposes an approach to simulate the function of the control part of a Grafcet model, translating it into C code in a Unix environment. First, the Grafcet/C generation schemes are established. The Grafcet model, described in graphic or text form, is transformed in an internal form and then to C code by a generation algorithm based on the previously found diagrams. The result is a program that simulates the operation of the automation in question and makes it possible to validate the functional specifications of sequential automation. This validation can be used for educational purposes, such as the learning of the Grafcet formalism, or corrective or evolutionary maintenance. Once the configuration, testing, and validation of the program are complete, it is possible to implement the object code on the microcontroller of the control system.

The success of a business, especially a multi-site extended enterprise, depends on the good management of all its distributed resources. It is difficult for a company to be successful if it does not have a reliable and optimal management of resources by avoiding overstocking of certain resources on a site Sitem ∈ E, and at the same time, the sub-storing of the same resources on another site Sitep ∈ E. In both cases, there is a lack of profit. In this paper, we will try to resolve this situation, by the proposal of an architecture based on the cooperative multi-agent systems paradigm combined with the Contract-Net protocol. We bring in an intelligent agent whose role is to warn in advance and for each item itemi ∈ Sitem, the coming of breakdowns and stock excesses by balancing the level of inter-site availability by a flow of resources of the same itemi by calling on the other E sites whose levels are in over-storage or under-storage.