OATAO is an open access repository that collects the work of Toulouse researchers and makes it freely available over the web where possible.Reactive scheduling using a multi-agent model: the SCEP framework B. Archimede*, T. CoudertLGP (Laboratoire G! enie de Production), ENIT ( ! Ecole Nationale d'Ing! enieurs de Tarbes), 47, Avenue d'Azereix, BP 1629, 65016 Tarbes, France AbstractMulti-agent systems have been successfully applied to the scheduling problem for some time. However, their use often leads to poorly unsatisfactory disappointing results. A new multi-agent model, called supervisor, customers, environment, producers (SCEP), is suggested in this paper. This model, developed for all types of planning activities, introduces a dialogue between two communities of agents leading to a high level of co-operation. Its two main interests are the following: first it provides a more efficient control of the consequences generated by the local decisions than usual systems to each agent, then the adopted architecture and behaviour permit an easy co-operation between the different SCEP models, which can represent different production functions such as manufacturing, supply management, maintenance or different workshops. As a consequence, the SCEP model can be adapted to a great variety of scheduling/planning problems. This model is applied to the basic scheduling problem of flexible manufacturing systems, and it permits a natural co-habitation between infinite capacity scheduling processes, performed by the manufacturing orders, and finite capacity scheduling processes, performed by the machines. It also provides a framework in order to react to the disturbances occurring at different levels of the workshop. r

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OATAO is an open access repository that collects the work of Toulouse researchers and makes it freely available over the web where possible.Production/maintenance cooperative scheduling using multi-agents and fuzzy logic Production/maintenance cooperative scheduling using multi-agents and fuzzy logic T. COUDERT y , B. GRABOT y * and B. ARCHIME Á DE y Within companies, production is directly concerned with the manufacturing schedule, but other services like sales, maintenance, purchasing or workforce management should also have an in¯uence on this schedule. These services often have together a hierarchical relationship, i.e. the leading function (most of the time sales or production) generates constraints de®ning the framework within which the other functions have to satisfy their own objectives. We show how the multiagent paradigm, often used in scheduling for its ability to distribute decisionmaking, can also provide a framework for making several functions cooperate in the schedule performance. Production and maintenance have been chosen as an example: having common resources (the machines), their activities are actually often con¯icting. We show how to use a fuzzy logic in order to model the temporal degrees of freedom of the two functions, and show that this approach may allow one to obtain a schedule that provides a better compromise between the satisfaction of the respective objectives of the two functions.

In the context of globalization and knowledge management, information technologies require an ample need of unprecedented levels of data exchange and sharing to allow collaboration between heterogeneous systems. Yet, understanding the semantics of the exchanged data is one of the major challenges. Semantic interoperability can be ensured by capturing knowledge from diverse sources by using ontologies and align these latter by using upper level ontologies to come up with a common shared vocabulary. In this paper, we aim in one hand to investigate the role of upper level ontologies as a mean for enabling the formalization and integration of heterogeneous sources of information and how it may support interoperability of systems. On the other hand, we present several upper level ontologies and how we chose and then used Basic Formal Ontology (BFO) as an upper level ontology and Common Core Ontology (CCO) as a mid-level ontology to develop a modular ontology that define emergency responders' knowledge starting from firefighters' module for a solution to the semantic interoperability problem in emergency management.

Nowadays, manufacturers have to share some of their resources with partners due to the competitive economic environment. The management of the availability periods of shared resources causes a problem because it is achieved by the scheduling systems, which assume a local environment where all resources are on the same site. Therefore, distributed scheduling with shared resources is an important research topic. In this communication, we introduce the architecture and behaviour of DSCEP framework (Distributed, Supervisor, Customer, Environment, and Producer) under shared resources situation with disturbances. We are using a simple example of manufacturing system to illustrate the ability of DSCEP framework to solve the shared resources scheduling problem in complex systems.

Throughout the history, the evolutions of the requirements for manufacturing equipments have depended on the changes in the customers' demands. Among the present trends in the requirements for new manufacturing equipments, there are more flexible and more reactive machines. In order to satisfy those requirements, this paper proposes a control and monitoring framework for machine tools based on smart sensor, on smart actuator and on agent concepts. The proposed control and monitoring framework achieves machine monitoring, process monitoring and adapting functions that are not usually provided by machine tool control systems. The proposed control and monitoring framework has been evaluated by the means of a simulated operative part of a machine tool. The communication between the agents is achieved thanks to an Ethernet network and CORBA protocol. The experiments (with and without cooperation between agents for accommodating) give encouraging results for implementing the proposed control framework to operational machines. Also, the cooperation between the agents of control and monitoring framework contributes to the improvement of reactivity by adapting cutting parameters to the machine and process states and to increase productivity.

Along with the rising concern of environmental performance, eco-labeling is becoming more and more popular. However, the complex process of eco-labeling is demotivating manufacturers and service providers to be certificated. The knowledge contained in eco-labeling criteria documents is not semantically exploitable to computers. Traditional knowledge base in relational data model is not interoperable, lacks inference support and is difficult to be reused. In our research, we propose a comprehensive knowledge base composed of interconnected OWL (Ontology Web Language) ontologies. This ontology based knowledge base allows reasoning and semantic query. In this paper, a modularization scheme about ontology development is introduced and it has been applied to EU Eco-label (European Union Eco-label) laundry detergent product criteria. This scheme separates entity knowledge and rule knowledge so that the ontology modules can be reused easily in other domains. Reasoning and inference based on SWRL (Semantic Web Rule Language) rules in favor of eco-labeling process is also presented.

Disaster response is a highly collaborative and critical process that requires the involvement of multiple government agencies and emergency responders (ERs) ideally working together under a unified command to enable a rapid and effective operational response. Following the 9/11 and 11/13 terrorist attacks, and the devastation of hurricanes Katrina and Rita, it is apparent that inadequate communication and a lack of interoperability among the ERs engaged on-site can adversely affect disaster response efforts. Within this context, we present a scenario-based terrorism case study to highlight the challenges of operational disaster command and response. In this work, which is based on the French emergency response doctrine, we introduce a semantics-based common operational command system that is designed to guarantee an efficient information flow among ERs. In particular, our focus is on offering to all ERs a real-time operational picture of the situation in order to enable multi-level coordination among firefighters, police, gendarmerie, healthcare units, public authorities, and other stakeholders. Our approach consolidates information in order to promote timely sharing among ERs. The proposed system is based on an ontology that has been developed to represent the different types of knowledge on the part of ERs, providing a shared vocabulary that covers a variety of interoperability concerns arising for example because data are collected in different formats, because the different functions of different stakeholders are not taken into account, and because there are failures of coordination among different groups of emergency responders.