SEMANTIC AGENT SYSTEMS

Towards a Reference Architecture for Semantic Agent Systems Applied to

Symposium Planning

Usman Ali

Fredericton, NB1

Outline

BackgroundOrganizationVirtual OrganizationOrganizational DesignsAgent ScenariosMulti Agent System FrameworksConclusion

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Semantic Web Vision

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Agent Scenario

Consider a Web-enabled method for saving the doomed crew of The Perfect Storm.

How could Web agents have helped?

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Organization

"An organization provides a framework for activity and interaction through the definition of roles, behavioural expectations and authorityrelationships (e.g. control)."

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Virtual Organization

"Virtual Organizations are a set of individuals and institutions that need to co-ordinate resources and services across institutional boundaries".

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Linked Data

Current Web

Documents

Semantic Web

Formal Ontologies

Middle way between formalism of Ontologies and information of documents.

Linked Data

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Software Personal Assistants

Software personal assistants (SPA) are an active research area that one day might change the face of our human organizations.

Organizational Structures

Star Ring Mixed/Random

Overload Speed

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Agent based Computing

Agent based computing merges two technologies, namely Artificial Intelligence (AI) and object-oriented distributed computing.In distributed object computing, objects can be located across a variety of platforms and in different processes and can communicate transparently with each other (by issuing method requests) as if they were located on a single machine.

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Importance of Agent oriented thinking

As real-world applications are becoming significantly more complex than before. Agent-oriented techniques provide a natural way for modelling complex systems, by decomposing its problem space into autonomous agents and their interactions.

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Agent Centered Versus Organisation Centered Approach

Agent Centered

States of an agent and of the relation between these states and its overall behaviour.

Organisation Centered

Concepts of ‘organizations’, ‘groups’, ‘communities’, ‘roles’, ‘functions’, etc. play an important role.

Classical New Approach

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Organization Design

In a distributed software architecture, sharing information or interaction has to be predefined which makes it a rigid distributed architecture environment.

Open Agent Architecture (OAA):

Flexible, dynamic communities of distributed software agents.Human users and software agents, in an OAA, express their requestsin terms of,“What will be done?”rather than "How will it be done?” Tools?

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Agent Oriented Modelling and Design

Scenario

A situation in a application involving actors and activities.

Structured Thinking

Agents start with an overall plan to solve the problem.

Unstructured Thinking

Actors can start from anywhere and build up a solution.

Actors can play roles based on their perception (mental states).

Agent oriented modelling and design.13

Multi Agent Frameworks

Academic World Business World

Presentation

SEARCHABLE14

EMERALD

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RULE RESPONDER

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Organizational Agent

The organizational agent represents the goals and strategies shared by each committee chair.

It contains rule sets that describe the policies and regulations of the RuleML Symposium.

Delegates incoming queries to the chair’s PAs.

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Personal Agent

• A personal agent assists a single chair

of the symposium, (semi-autonomously) acting

on his/her behalf.• Each personal agent contains a rule-base

FOAF-like profile.• It contains a FOAF*-like fact profile plus

FOAF-extending rules to encode selected

knowledge of its human owner.18

External Agent

• External agents exchange messages with the OA. They submit queries and receive answers.

• End users, as external agents, interact with the OA using a Web (HTTP) interface to the Symposium Planner.

• Support for simultaneous external agents Many EAs can communicate with the OA.

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Query Delegation

Publicity Chair

Agents

Sponsoring

Publicity Chair

.

..

Liaison Chair

General Chair

..

.

.

.

.

Challenge Chair

Challenge

Demos

Media Partners

Sponsors

Responsible

Accountable

Press Release

Challenge Chair

Liaison Chair

General Chair

Metatopics ...

.

..

.

..

Registration

Visa Letter

.

..

Program Chair

.

..

.

..

Program Chair

Submissions

Presentations...

Properties:20

Rule Engines

Prova: Prolog + Java

OO jDREW: Object Oriented java Deductive Reasoning Engine for the Web

OO jDREW is used to realize thepersonal agents of Rule Responder

It implements Hornlog RuleML for agent reasoning (Horn logic rules)Supports rules in two formats:

POSL: Positional Slotted presentation syntax

RuleML: XML interchange syntax

Prova is mainly used to realize the organizational agents of Rule Responder

It implements Reaction RuleML for agent interaction (event-condition-action rules)

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COMMUNICATION MIDDLEWARE

Mule Enterprise Service Bus (ESB)

Mule is used to create communication end points at each personal and organizational agent of Rule Responder

Mule supports various transport protocols(i.e. http, jms, soap)

Rule Responder uses http and jms as transport protocols

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MULE ENTERPRISE SERVICE BUS

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Reaction RuleML

Reaction RuleML is a branch of the RuleML family that supports actions and events.

When two agents want to communicate, each others’ Reaction RuleML messages are sent through the ESB.

The ESB carries RuleML queries (requests), answers (results), and rule bases to/from agents.

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RuleResponder versus Emerald

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Multi Agent System Interoperation

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REFERENCE ARCHITECTURE OF SYMPOSIUMPLANNER

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Online Use Case Demo

http://www.defeasible.org/ruleml2011ijcai/?q=node/25

http://de.dbpedia.org/redirects/ruleml/ACE2ReactionRuleML/index.jsp

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Conclusion

• The SymposiumPlanner and many other applications like it, can truly provide the basis for gradual transformation of our workplace into an efficient and productive environment.

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