Reasearch center in scientific and technical information Cerist

1. Reasearch center in scientific and technical information Cerist A formalapproach of a self organizingprotocolinspired by bacateriacolony: Production system application Presented by: Hakima Mellah Bionetics 2009 Avignon, Dec 9-11

2. Plan

3. Introduction The coordination and the maintenance of connectivity in a network take from peer to peer systems (P2P). One of the major problems characterizing this type of systems is the establishment and the maintenance of the co-operation between nodes. However, this difficulty can arise in any communication network, ad hoc network, multi agents systems(for which the node will be regarded as an agent,),… New communication flowsemerge IS2 IS2 IS3’ IS1 IS1 IS2 IS2 IS3 IS1 IS1 IS3 IS4 IS4 IS4 IS4

4. Production Systems • What is? A production system is a set of resources realizing a productive activity. The production is the transformation of resources (machines and materials) leading to the creation of goods or services. The transformation is done by a succession of operations (tasks) that use resources (machines and operators), and modify the raw materials or components that enter into the PS in order to create outgoing finished products of this system and assigned to be consumed by customers. Systems Theory (i) Information and decision subsystem (ii) physical production subsystem

5. Machine E Machine B Task1 Task 4 Task 5 Task6 Task2 Machine A Machine C oroduct Machine F Ffinishedproduct Task 3 Task7 Transpor meant Machine D Product semi-finished Produit semi-finished stock Production Systems Production System Example Features

6. Production Systems • What? The critical and important problem to solve within PS is fault tolerance. The control system must provide very powerful mechanisms fault tolerance in order to ensure the continuous operations of PS that are detection, prevention and correction, • How? MULTI-AGENTS SYSTEMS production management ? Enterprise requirements Competitivity. Very high reliability constraints. Minimising dysfonctionning. What can offer a MAS decentralised control New manners to communicate.

7. Multi Agent Systems • MAS MAS iscomposed by autonomuousentities, called agents. Theyevolve in a commonenvironment, have a collective behaviour to reach a desiredfunction. • Communication protocols: ContractAcquaintances Net protocol Model • Organisation & self organisation • Organisation is the waythat a set isconstituted and the action to organise. • By SO, an agents organisation allows agents to adapt to changing situations. S P C P C P C P

8. The self organizing protocol The principal goal through this protocol is to ensure: (i) New bonds of communications (ii) an important co-operation between the agents of the same neighbourhood; (iii) a MAS self organization made concrete by the emergence of communication bonds, that make cooperate agents which are not directly connected; (iv) take decision to add/remove agents when it is necessary;

9. The self organizingprotocol • Concepts within BC Computational interpretation • Food Energie /information • Removing food source Destroy a link between sources, or the source itself. • Pattern communication structure (organisation) • Bacteria IS component • Chemotaxis Search direction • Gradient morphogen Distance compared to an IS; information of position • Inhibition & local competition Information on decision •  Local Control Failures detection

10. The self organizingprotocol Most important primitives Positioningprocess Election process Routingprocess Checkingprocess Groupingprocess

11. The self organizingprotocol Positioning process Morphogen Gradient and information of position: -More the morphogenisdiffused and more its concentration ishigher. -Each gradient morphogenimplies an activityassured by a bacteria group -morphogen concentration represents the distance between a bacteria and a source of food -Morphogenallows the bacteria to know whereitissituatedbetweentwodifferents sources Figure 3. Morphogen diffusion

12. The self organizingprotocol Election process • Local inhibition and competition • Within a group, cells differentiate to take a new role. one cell that decide to differentiate, diffuses a signal (morphogen) that inhibit others to differentiate.

13. The self organizingprotocol • Mathematical formulation of positioningprocess: • A position message: position(ai, role, posi), • i IN, aiA, the whole of agents positions with their identification are stored in a table. •  j  IN, aiA, if eij =1 aj aj is a direct neighbour of ai and can received ai messages. •  k  IN, akA / eik =1 • ak receives position(ai, role, posi), • ak receives position(ai, role, posi) for the first time Possrcposi ; poskpossrc +1;

14. MAS for Production system • Piloting ressource Agent(PRA) • User Agent (UA) • Interface Agent(IA) Setting production plan UA Dispatching tasks to PRA IA Realising piloting system functions PRA

15. MAS for Production system 1. Agent failure • (i)RA(breakdown) is the alone agent of another RA. • (ii)RA has severalneighbours. 2. Communication bond failure i)RA isolated or the system is broken down into two subsystems. (ii)Isolated RA is a neighbor of an agent RA belonging to a sub system. (iii)The two RA belong to the same subsystem. -Soft failure Agent in failure Communication bond destroyed

16. MAS for Production system -Hard failure -At least one RA can execute the tasks of the agent responsible for the breakdown resource -No agent can perform the tasks of the breakdown agent and in this case the operator has to intervene. t Fig. 2. Collaboration diagram of the system functioning

17. Conclusion Production system is able to be fault tolerant by: • Detecting and localizing a failure • finding a solution to each MAS situation • Minimizing operator intervention

18. Perspectives • Realize the study on a concrete case of production systems. • Considering a MAS in multi postes

19. Thanks THANK YOU FOR YOUR KIND ATTENTION Algiers by night

20. Université SAAD DAHLEB, Blida. USDB ADAPTATION ET MISE EN ŒUVRE D’UN PROTOCOLE AUTO-ORGANISABLE DANS LE CAS DE LA GESTION DE LA PRODUCTION Présenté par : RAIAH AHMED & TIGUMOUNINE AREZKI

21. Reasearch center in scientific and technical information Cerist A formalapproach of a self organizingprotocolinspired by bacateriacolony: Production system application Presented by: Hakima Mellah Bionetics 2009 Avignon, Dec 9-11