Multi Agent and Holonic Manufacturing Control

Abstract

Future Manufacturing Systems 96 and intelligent ones, namely the agent-based and holonic manufacturing control system. In section 3, we present two case studied including real-time scheduling method for holonic manufacturing system and agent-based dynamic integrated process planning and scheduling in flexible manufacturing system. Finally, we briefly discuss about realizing the agent based manufacturing system by applying the ORiN (Open Robot Interface Network) architecture which recently has been developed for manufacturing automation. 2. Manufacturing control systems 2.1 Traditional approach to manufacturing control problem The manufacturing control is concerned with managing and controlling the physical activities in the factory aiming to execute the manufacturing plans, provided by the manufacturing planning activity, and to monitor the progress of the product as it is being processed, assembled, moved, and inspected in the factory. Algorithms at this level are used to decide what to produce, how much to produce, when production is to be finished, how and when to use the resources or make them available, when to release jobs into the factory, which jobs to release, job routing, and job/operation sequencing (Baker, 1998). Due to its complexity, especially the high number of interactions between the different components and the variety of functions executed, manufacturing control systems are traditionally implemented using centralized or hierarchical control approaches, comprising, the following main components: planning, scheduling, execution (i.e. dispatching, monitoring, diagnosis and error recovery) and machine/device control. Each one of these components operates in a specific temporal horizon, ranging from weeks at the strategic level to seconds at the shop floor. The traditional approach to manufacturing control systems based on centralized or hierarchical control structures, presents good characteristics in terms of productivity, essentially due to its intrinsic optimization capabilities. However, dynamic and adaptive response to change is, currently, the key to competitiveness, and the traditional approaches to manufacturing control typically fall into large monolithic and centralized software packages that are developed and adapted case by case, requiring a huge and expensive effort to implement, maintain or re-configure. In conclusion, they are not adequate because they do not support efficiently the current requirements imposed to manufacturing systems, namely in terms of flexibility, expansibility, agility and re-configurability. 2.2 Agent-based manufacturing control The multi-agent system paradigm derives from the distributed artificial intelligence (DAI) field, being characterized by decentralization and parallel execution of activities based on autonomous entities, called agents. The definition of agent concept is neither unique nor consensual (Russel & Norvig, 1995; Wooldridge & Jennings, 1995;Wooldridge, 2002). Despite some definitions and interpretations for agents, a suitable definition is: ...

Pharmaceutical policy and market in Iran: past experiences and future challenges

“…Some drugs not manufactured in Iran were designated by the Iranian Food and Drug Department as essential and could be only imported by two state owned companies, and prescribed by brand name. [11] These rationalisation measures reduced the numbers of drugs available (only around 1000 of the previously available drugs were included in the Iranian Drugs List -the other 3000 drugs were considered 'me-too' drugs, or simple duplication, and unnecessary [12] ) while increasing supply and often dramatically reducing the price; e.g. the price of a Mebendazole tablet decreased to one-eleventh of its previous level (Dr 02).…”

“…[14] From the industry perspective, the lack of market competition and guaranteed price regardless of quality led to unfair profit, and the bureaucratic barriers were major disincentives to innovation and change hindering development and growth. [9,11,14] From 1989, as a part of broader economic and social development programme in Iran, some market-oriented reforms were started in the pharmaceutical industries. The first was to transfer the state owned pharmaceutical industries to the private and semi-private sectors, which started from 1989 and was completed by 1994.…”