Multi Agent System & Holonic Manufacturing System

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Some questions

o What are the appropriate control philosophies for

Complex Manufacturing systems?

Why????

Holonic Manufacturing system

o Is Object -Oriented and / or Entity relationship approach sufficient to establish a complex software engineering system?

o Are there any differences between Agent and Holon?

The Holonic concept

The Holonic idea is a new paradigm develop to organize activities and meet the agile, scalable ,robust and fault-tolerant requirements, overcomes many difficulties faced by existing convectional, rigid systems in manufacturing, offices etc.

Holonic idea or concept is not a method or a process but a philosophy. A guiding philosophy for effective and efficient way of getting a performance better than the traditional approaches in use today

This concept can be applied to our day to day life, activities as long as efficiency is needed to be measure. Holonic idea have been applied in offices, business, industry, university.

So, it becomes paramount for us to have a full understanding of this guiding philosophy for efficiency

HOLONIC PHILOSPHY

What are Holons?

 It is a combination of holos (a greek word meaning whole) and suffix on (meaning particles or part)

 A holon, as Koestler devised the term, is an identifiable part of a system that has a unique identity, yet is made up of subordinate parts and in turn is part of a larger whole.

 It is an autonomous and co-operative building block of a manufacturing system for transforming, transporting, storing and/or validating information and physical objects.

Holon’s Properties

 Autonomy: the capability of an entity to create and control the execution of its own plans and/or strategies

 Co-operation : a process whereby a set of entities develops mutually acceptable plans and executes these plans.

 A holon self-regulates and respond to the environmental changes by using flexible strategies, and the changes are fed back to the center of its controller to continuously adjusts its course of action. The essential attributes of holons includes autonomy and cooperativeness

Holonic Systems

 Holarchy: a system of holons that can cooperate to achieve a goal or objective. The holarchy defines the basic rules for cooperation of the holons and thereby limits their autonomy.

 Holonic manufacturing system: a holarchy that integrates the entire range of manufacturing activities from order booking through design, production, and marketing to realize the agile manufacturing enterprise

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HOLONIC SYSTEMS

Cooperative relationships among holons

Comparison of holonic with other systems

Agent

In terms of origin, the agent can be defined as the amount of sub-classes which their combination establish the upper-class .

To exemplify, In manufacturing ,shops’(agent) combination make a bigger unit which is called Factory.

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Agents have their roots in the computer science (artificial intelligence area) and the Holons in the computer integrated manufacturing domain, focusing on the problem associated with the flexible manufacturing systems

Agent

Agent

It perceives the world in which it is situated.

It has the capability of interacting with other agents.

It is pro-active in the sense that it may take the initiative and persistently pursues its own goals.

MAS : Multi-agent system

A collection of, possibly heterogeneous, computational entities, having their own problem solving capabilities and which are able to interact in order to reach an overall goal.

MAS is seen as a system revealing a kind of synergy that would not be expected from the sum of its component agent.

Agents’ behavior

Coordination protocol b/w agent is nearly always derived from

Contract Net (CNet)

Customer Agent

Task

Announcement

Bid Evaluation Bid Collection

Task offer construction

Task offer submission

Task Commitment

Server Agent

Task

Announcement monitoring

Bid construction

Bid Submission

Task offer reception

Task offer acceptance

Task offer evaluation

Agents’ behavior (2/2)

 Three classes of agent nodes.

 Service Manager Node

 Service Provider Node

 Contractor Node

Potential

Service Providers Service Providers

Manager

Contractor

Task Announcement Receive bids Award bids

Agent Technology

An intelligent agent is a software entity which exhibits, in some significant measure, autonomy, intelligence, and environmental awareness, and which interacts with its environment to achieve internal goals;

A multi-agent system (MAS) is a software system in which program modules (the individual agents) are given autonomy and intelligence and an underlining coordination mechanism (implementing rules for collaboration, like for holarchies) which enables collaboration between such modules (agents) to attain system objectives

Holons & Agent

The debate on clarifying the difference between holons and agents is an ongoing issue in the research communities.

Given the essentially different path on which each concept was developed the question itself is inappropriate.

In response to the need for modeling the complexity of interactions in large scale Holonic systems, agent technology has emerged as a paradigm for structuring, designing and building software systems that require complex interactions between autonomous distributed Holons.

Holons & Agent

The agent paradigm models systems focusing on the underlining dynamics defined by the interactions between their parts. In contrast to the passive way in which objects communicate by invoking methods in one another in a way controlled externally by the user (e.g., from a

‘main’ program), agents are capable to initiate communication and decide (like a human) when and how to respond to external stimuli

(e.g.,, manifested upon them as requests from other agents).

From this perspective the agent paradigm extends the object paradigm in that agents can be regarded as proactive objects that have an internal mechanism which governs their behavior enabling them to initiate action as well as to respond to the outside environment in an autonomous way.

Thank you for your attention

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