Content deleted Content added
No edit summary |
No edit summary |
||
Line 3:
'''Distributed Artificial Intelligence (DAI)''' is a subfield of [[artificial intelligence]] research dedicated to the development of distributed solutions for complex problems regarded as requiring intelligence. DAI is closely related to and a predecessor of the field of [[Multi-agent system|Multi-Agent Systems]].
==
Distributed Artificial Intelligence (DAI) is an approach to solving complex learning, planning, and decision making problems. It is embarrassingly parallel, thus able to exploit large scale computation and spatial distribution of computing resources. These properties allow it to solve problems that require the processing of very large data sets. DAI systems consist of autonomous learning processing nodes ([[Intelligent_agent|agents]]), that are distributed, often at a very large scale. DAI nodes can act independently and partial solutions are integrated by communication between nodes, often asynchronously. By virtue of their scale, DAI systems are robust and elastic, and by necessity, loosely coupled. Furthermore, DAI systems are built to be adaptive to changes in the problem definition or underlying data sets due to the scale and difficulty in redeployment.
DAI systems do not require all the relevant data to be aggregated in a single ___location, in contrast to monolithic or centralized Artificial Intelligence systems which have tightly coupled and geographically close processing nodes. Therefore, DAI systems often operate on sub-samples or hashed impressions of very large datasets. In addition, the source dataset may change or be updated during the course of the execution of a DAI system.
==Goals==
There are many reasons for wanting to distribute intelligence or cope with multi-agent systems. Mainstreams in DAI research include the following:
* Parallel problem solving: mainly deals with how classic artificial intelligence concepts can be modified, so that [[multiprocessor]] systems and clusters of computers can be used to speed up calculation.
* Distributed problem solving (DPS): the concept of [[Intelligent agent|agent]], autonomous entities that can communicate with each other, was developed to serve as an [[abstraction]] for developing DPS systems. See below for further details.
* Multi-Agent Based Simulation (MABS): a branch of DAI that builds the foundation for simulations that need to analyze not only phenomena at [[macroscopic|macro]] level but also at [[microscopic scale|micro]] level, as it is in many [[social simulation]] scenarios.
The objectives of Distributed Artificial Intelligence are to solve the reasoning, planning, learning and perception problems of [[Artificial_intelligence|Artificial Intelligence]], especially if they require large data, by distributing the problem to autonomous processing nodes (agents). To reach the objective DAI require:
* A [[Distributed_computing|distributed system]] with robust and elastic computation on unreliable and failing resources that are loosely coupled
* Coordination of the actions and communication of the nodes
* Subsamples of large data sets and [[Online_machine_learning|online machine learning]]
==History==
In the 1970 distributed artificial intelligence emerged as a subfield of artificial intelligence that dealt with interaction of intelligent agents[2]. Distributed artificial intelligence systems were conceived as a group of intelligent entities, called agents, that interacted by cooperation, by coexistence or by competition. DAI is categorized into Multi-agent systems and distributed problem solving [1]. In [[Multi-agent_system|Multi-agent systems]] the main focus is how agents coordinate their knowledge and activities. For distributed problem solving the major focus is how the problem is decomposed and the solutions are synthesized.
==Examples==
Multi-agent systems and distributed problem solving are the two main DAI approaches. There are numerous applications
and tools.
==Approaches==
Two types of DAI has emerged:
* In [[Multi-agent_system|Multi-agent systems]] agents coordinate their knowledge and activities and reason about the processes of coordination. Agents are physical or virtual entities that can act, perceive its environment and communicate with other agents. The agent is autonomous and has skills to achieve goals. The agents change the state of their environment by their actions. There is a number of different coordination techniques[3].
* In distributed problem solving the work is divided among nodes and the knowledge is shared. The main concerns are
task decomposition and synthesis of the knowledge and solutions.
DAI can apply a bottom-up approach to AI, similar to the [[Subsumption_architecture|subsumption architecture]] as well as the traditional top-down
approach of AI. In addition, DAI can also be a vehicle for [[Emergence|emergence]].
==Applications==
Areas where DAI have been applied are:
* Electronic commerce, e.g. for [[Trading_strategy|trading strategies]] the DAI system learns financial trading rules from subsamples of very large samples of financial data
* Networks, e.g. In [[Telecommunication|telecommunications]] the DAI system controls the cooperative resources in a WLAN network http://dair.uncc.edu/projects/past-projects/wlan-resource
* [[Scheduling_(production_processes)|Routing]], e.g. model veichle flow in transport networks
* [[Scheduling_(production_processes)|Scheduling]], e.g. [[Flow_shop_scheduling|flow shop schedueling]] where the resource managment entity ensures local optimization and cooperation
for global and local consistency[4]
* Multi-Agent systems, e.g. [[Artificial_life|Artificial Life]], the study of simulated life
==Tools==
* [http://groups.csail.mit.edu/EVO-DesignOpt/groupWebSite/index.php?n=Site.BP#ECStar-fig ECStar], a distributed rule-based learning system
==Agents and Multi-agent systems==
Line 14 ⟶ 52:
Notion of Multi-Agents:Multi-Agent system is defined as a network of agents which are loosely coupled working as a single entity like society for problem solving that an individual agent cannot solve.
==
The key concept used in DPS and MABS is the abstraction called [[software agent]]s. An agent is a virtual (or physical) [[Wiktionary:autonomy|autonomous]] entity that has an understanding of its environment and acts upon it. An agent is usually able to communicate with other agents in the same system to achieve a common goal, that one agent alone could not achieve. This communicate system uses an [[agent communication language]].
Line 29 ⟶ 67:
* [[Soar (cognitive architecture)|Soar]] (a rule-based approach)
==
The Basic Problems of Distributed AI are:
Line 53 ⟶ 91:
== References ==
{{Reflist}}
<!--- After listing your sources please cite them using inline citations and place them after the information they cite. Please see http://en.wikipedia.org/wiki/Wikipedia:REFB for instructions on how to add citations. --->
*[1] A. Bond and L. Gasser. Readings in Distributed Artificial Intelligence. Morgan Kaufman, San Mateo, CA, 1988.
*[2] Brahim Chaib-Draa, Bernard Moulin, René Mandiau, and P Millot. Trends in distributed artificial intelligence.
Artificial Intelligence Review, 6(1):35-66, 1992.
*[3] Nick R Jennings. Coordination techniques for distributed artificial intelligence. Foundations of distributed artificial
intelligence, pages 187-210, 1996.
*[4] Damien Trentesaux, Philippe Pesin, and Christian Tahon. Distributed artificial intelligence for fms scheduling, control
and design support. Journal of Intelligent Manufacturing, 11(6):573-589, 2000.
== Further reading ==
* Hewitt, Carl; and Jeff Inman (November/December 1991). "DAI Betwixt and Between: From 'Intelligent Agents' to Open Systems Science" ''IEEE Transactions on Systems, Man, and Cybernetics''. Volume: 21 Issue: 6, pps. 1409–1419. ISSN 0018-9472
| |||