www.ijecs.in International Journal Of Engineering And Computer Science ISSN:2319-7242 Volume 2. Issue 10 October 2013 Page No. 3015-3018 Swarm Intelligence and Knowledge Acquisition 1 Nivedita Joshi,2Pooja Singh 1 Student, B.Tech (IT), Dronacharya College of Engineering, Maharishi Dayanand University Gurgaon, Haryana,India Nivedita.joshi92@yahoo.co.in 2 Student, B.Tech (IT), Dronacharya College of Engineering, Maharishi Dayanand University Gurgaon, Haryana,India Poojasingh.8dec@gmail.com ABSTRACT Computing is rapidly moving away from traditional computers. Programs in the future will run on collections of mobile processors that interact with the physical world and communicate over ad hoc networks. We can view such collections as swarms. As with natural swarms, such as a beehive or ant colony, the behavior of a computational swarm emerges from the behaviors of its individual members. This research paper focuses on swarm techniques for creating, understanding and validating properties of programs that execute on swarms of computing devices.The paper strives on identifying and understanding about swarm practices in principled ways and investigates the technique based on both experimental and analytical approaches. Keywords: Self-Organization, Stigmergy, Data Mining, Ant Colonization, Particle Swarm Organization (PSO). 1. Introduction Swarm intelligence is a collection of decentralized and selforganized, artificial or natural agents forming an intelligent network.Gerardo Beni and Jing Wang first introduced the term “SWARM INTELLIGENCE” in 1989 in the context of cellular robotic systems.These agents,artificial or natural,are interacting locally with each other as well as their surrounding environment without a centralized plan. The inspiration comes from nature such as ants foraging,bees, and social insects.These agents follow very simple protocols without involving a detailed structure and still each individual agent is aware of behaving and performing intelligently.The interactions occurring between the agents lead to an intelligent global behavior unknown to individual agents. Examples of natural agents of SI include ant colonies, bird flocking, animal herding, bacterial growth, and fish schooling. ‘Self-organization is a set of dynamical mechanisms whereby structures appear at the global level of a system from interactions of its lower-level components.’ (Bonabeau et al, in Swarm Intelligence, 1999) 2.2.1 Ant Foraging A colony of ants is able to forage to the nearest and most promising food source. The other foragers of the same colony are recruited by pheromone trails. A successful ant returns to the nest leaving behind a "smell" on the ground. This smell guides the movements of other foragers. When the latter foragers also find a food source at the end of the pheromone trail they reinforce the earlier trail by leaving behind new pheromone marks. Thus a network of pheromone trail is constructed in a selforganized manner.So the foragers are able to adapt to different food sources,thus avoiding over-recruitment. The features of such resulting distribution are behavior updating,adaptive patterns and trail following.The models of adaptive foraging form the basis for algorithms that can be applied to routing in communication networks. 2. Principal Mechanism of Swarm Intelligence 2.2 Self-Organization 1 These algorithms are applied to problems like the Travelling Salesman and related network-based problems. Nivedita Joshi, IJECS Volume 2. Issue 10 October 2013 Page No.3015-3018 Page 3015 Reinforcement of edges that are rated as good is combined with a mechanism for pheromone decay leading an optimal solution. Fig. 1 Pheromone Trail Fig. 2 Nest Building Features of self-organization: 2.2.2 Division of Labour 1. Multiple interactions A colony of ant adjusts to its allocated task. Even if a large partition of specialized workers are artificially removed, it still maintains its functions.This type of adaptation occurs without any evaluation of the global situation, any direct communication or centralized control.Such models are based on self-organization and deals with response thresholds.Every ant in the colony is able to make out the need for fulfillment of some task such as storing the incoming food, brood care etc. If this spur is strong enough, the ant has a higher chance of getting involved in the task associated with the spur(stimulus).The ant adapts its threshold for the task it completes successfully. The strengthening of such task, which the ant has done often, leads to specification in a colony of identical workers. Such model can be used for task allocation mechanism in an artificial multi-agent system. 2. Strengthening activities by positive feedback 3. Balancing activities by negative feedback 4. Strengthening random variations 2.3 Stigmergy The term Stigmergy is derived from the Greek word stigma (sign) + ergon (work). It is the indirect interaction between agents and captures the notion that an agent’s action leave signs in the environment, which the other agents sense that stimulate their subsequent actions.In this way the subsequent actions of the agents tend to reinforce, leading to modification of the environment. The agents are extremely simple, lacks any memory or intelligence and are unaware of each other. 2.2.3 Cemetery Organization In ant colonies, distributed objects are loaded and stored in clusters, such as collecting corpses or larval sorting, without any central plan as where to load the items.A simple agent based model explains this phenomenon. The agent carrying an object drops it when it finds similar objects and picks up an item when the surrounding objects are of different kind. Such models can be used for data analysis or graph partitioning in a two-dimensional space or implemented in swarm of robots moving around and picking pucks. 2.2.4 Nest Building The social insects construct complex nest architectures without any global representation. This can be explained by the framework of micro-rules such as the configuration of bricks for example surrounding a simulated wasp indicating that whether agent should deposit a new brick or move on. Such rules can be used to examine random space filling activities (eggs are likely to be layered in the neighborhood of brood)and to determine the behavior of single entity(random movement of queen over the combs). 1 Fig. 3 Mechanism 2.3.1 Termite Mound Initially termites wander around randomly carrying mud and depositing it at random places. The deposits are created in a haphazard manner, which tends to stimulate the other insects to add more mud in the same place. The small heaps grow into large complex columns that eventually come together to form intricate cathedral of arches. That is the traces left in the environment by an agent or action incites the performance of a next action. The partially executed work of the ones provides information to the others about where to make their own contribution. Features of Stigmergy: Nivedita Joshi, IJECS Volume 2. Issue 10 October 2013 Page No.3015-3018 Page 3016 1. Planning: the agent needs to know the current state of their activity; the next step or result is irrelevant for their present work. 2. Memory: the agents lack any memory or intelligence; no information about the last state of the work needs to be stored except in the medium. 3. Communication: there is no need for the agents to know who does what that is no information needs to be transferred between the agents. 4. Mutual awareness: each agent works independently 5. Simultaneous presence: there is no need for the agents to be present at the same time or at the same place; tasks are registered in the medium. 6. Imposed sequence: actions are not started until right conditions are in place. Workflow emerges spontaneously. Completion of one task triggers the initiation of further tasks. 7. Commitment: agents do not need to commit to a particular task. When an agent becomes unavailable or quits, another one automatically replaces it. 8. Centralized control: there is no centralized control; global organization emerges from local interactions. 3. Knowledge Discovery Data mining, also known as information discovery, knowledge extraction; is a process of extraction of information from a data set and transforming it into an understandable structure for further use. Steps in knowledge discovery: 1. Understanding the application data and classifying the goals of KDD process. 2. Creating target data set 3. Data preprocessing by performing operations such as removal of noise, identifying and handling missing data fields etc. 4. Using data reduction and transformation methods to reduce the effective number of variables and finding useful features for representing the data. 5. Achieving the goals of knowledge discovery through data mining methods like clustering, summation, classification etc. Fig. 4 Steps in Knowledge Discovery Swarm intelligence based methods such as Ant Colony Optimization and Particle Swarm Optimization (PSO) can be used for discovering patterns in large data sets. Such methods can be used in KDD(Knowledge Discovery in Databases) process. Deneubourg et al first introduced the ant colony based clustering algorithms by imitating the naturally occurring phenomena. In ant colonies, the items are loaded in heaps such as clusters of corpses and cemeteries without any central plan. The basis of this mechanism is the attraction between dead items mediated by the ant workers. This positive & auto- catalytic feedback leads to formation of larger clusters. Lumer and Faieta proposed an algorithm based on a response threshold function. The behavior of ants associated with loading and unloading of objects use a combination of different thresholds. The general idea of data clustering is that isolated objects should be picked up and dropped at a location where more such items are present. Abraham and Ramos proposed an algorithm to discover Web usage patterns. Web usage mining has become very important for effective web site management, personalization, business and support services, network traffic flow analysis etc. Particle Swarm Optimization (PSO) method can be used for recognizing patterns and image processing. PSO is a population based search method that optimizes a problem by iteratively improving a candidate solution. In PSO each particle is associated with velocity. The particles are moved in search space according to some mathematical formulae until it is guided towards the bestknown positions in the search space. Particle swarm intelligence combined with classical optimization methods can be used for Visual data mining. Visual data mining becomes difficult when applied to massive data sets due to limits of both screen resolution, human visual system resolution as well as the limits of available computational resources. 4. Conclusion 1 Nivedita Joshi, IJECS Volume 2. Issue 10 October 2013 Page No.3015-3018 Page 3017 Swarm intelligence is a computational intelligence technique to solve complex real-world problems. It involves the study of collective behavior of individuals in a population who interact locally with one another and with their environment in a decentralized control system. Through this research paper we introduced the basic concept of swarm intelligence: self-organization where the agents perform tasks without any centralized plan; Stigmergy where the agent’s (unaware of each other) actionleave signs in the environment, which the other agents sense and incite their subsequent actions. . We then described the knowledge discovery terminologies and also illustrated the ongoing works of swarm intelligence in knowledge discovery with an emphasis on ant colony optimization and particle swarm optimization. References [1] Bernstein, Jeremy. "Project Swarm" technology inspired by swarms in nature. [2]Karaboga, Dervis (2010) algorithm" Scholarpedia 5. "Artificial Report on bee colony [3] Engelbrecht, Andries “Fundamentals of Computational Swarm Intelligence”. [4]Miller, Peter (July 2007), "Swarm Theory", National Geographic Magazine [5]C Grosan, Abraham, M Chis - Swarm Intelligence in Data Mining, 2006 - Springer [6]Marsh, L. &Onof, C. (2007) "Stigmergic epistemology, stigmergic cognition." [7]Ant Colony Optimization by M acroDoriga and Thomas Stutzle, MIT Press [8]Shell, D., &Mataric, M. (2003). On the use of the term “Stigmergy.” In Proceedings of the second international workshop on the mathematics and algorithms of social insects 1 Nivedita Joshi, IJECS Volume 2. Issue 10 October 2013 Page No.3015-3018 Page 3018