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PRESENTED BY:
 GANESH PAUL
    TT – IT(02)
What is Soft Computing?
Soft computing is an emerging approach to computing
 which parallel the remarkable ability of the human
 mind to reason and learn in a environment of
 uncertainty and imprecision.
Some of it’s principle components includes:
Neural Network(NN)
Fuzzy Logic(FL)
Genetic Algorithm(GA)
These methodologies form the core of soft computing.
GOALS OF SOFT COMPUTING
The main goal of soft computing is to develop
 intelligent machines to provide solutions to real world
 problems, which are not modeled, or too difficult to
 model mathematically.
It’s aim is to exploit the tolerance for
 Approximation, Uncertainty, Imprecision, and Partial
 Truth in order to achieve close resemblance with
 human like decision making.
SOFT COMPUTING -
DEVELOPMENT HISTORY
Soft      = Evolutionary +      Neural +         Fuzzy
Computing   Computing           Network          Logic
Zadeh       Rechenberg          McCulloch        Zadeh
1981        1960                1943            1965



Evolutionary = Genetic    + Evolution +   Evolutionary + Genetic
Computing      Programming Strategies     programming Algorithms
Rechenberg Koza             Rechenberg    Fogel          Holland
1960           1992         1965          1962            1970
NEURAL NETWORKS
An NN, in general, is a highly interconnected network of
 a large number of processing elements called neurons
 in an architecture inspired by the brain.
NN Characteristics are:-
Mapping Capabilities / Pattern Association
Generalisation
Robustness
Fault Tolerance
Parallel and High speed information processing
Neuron
                             Biological neuron




Model of a neuron
          6
ANN ARCHITECTURES
             X1              y1                   X1                   z1

                                                             y1


            X2               y2
                                                 X2
                                                                       z2

                                                             y2
            X3               y3
                                                 X3                    z3

     Input Layer   Output Layer             Input Layer Hidden Layer Output Layer
1.Single Layer Feedforward Network       2.Multilayer Feedforward Network
                                         Xi - Input Neuron
       X1                         z1

                    y1                   Yi - Hidden /Output Neuron
       X2                         z2
                    y2

                                  z3
                                         Zi - Output Neuron
       X3


 Input Layer Hidden Layer Output Layer   i = 1,2,3,4…..
3.Recurrent Networks
LEARNING METHODS OF ANN
                           NN Learning
                            algorithms


SSupervised                Unsupervised     Reinforced
 Learning                    Learning        Learning


  Error
Correction    Stochastic          Hebbian    Competitive



Least Mean
  Square          Backpropagation
FUZZY LOGIC
Fuzzy set theory proposed in 1965 by A. Zadeh is a
  generalization of classical set theory.
In classical set theory, an element either belong to or
  does not belong to a set and hence, such set are
  termed as crisp set. But in fuzzy set, many degrees of
  membership (between o/1) are allowed
FUZZY VERSES CRISP
FUZZY                           CRISP
IS R AM HONEST ?
                                IS WATER COLORLESS ?
                   Extremely
                   Honest(1)                    YES!(1)

                  Very
 FUZZY         Honest(0.8)        CRISP

                   Honest at
                   Times(0.4)                   NO!(0)


                Extremely
               Dishonest(0)
OPERTIONS
CRISP            FUZZY
1.Union          1.Union
2.Intersection   2.Intersection
3.Complement     3.Complement
4.Difference     4.Equality
                 5.Difference
                 6.Disjunctive Sum
PROPERTIES
CRISP                          FUZZY
 Commutativity                 Commutativity
 Associativity                 Associativity
 Distributivity                Distributivity
 Idempotence                   Idempotence
 Identity                      Identity
 Law Of Absorption             Law Of Absorption
 Transitivity                  Transitivity
 Involution                    Involution
 De Morgan’s Law               De Morgan’s Law
 Law Of the Excluded Middle
 Law Of Contradiction
GENETIC ALGORITHM
Genetic Algorithms initiated and developed in the early
 1970’s by John Holland are unorthodox search and
 optimization algorithms, which mimic some of the
 process of natural evolution. Gas perform directed
 random search through a given set of alternative with
 the aim of finding the best alternative with respect tp
 the given criteria of goodness. These criteria are
 required to be expressed in terms of an object
 function which is usually referred to as a fitness
 function.
BIOLOGICAL BACKGROUND
All living organism consist of cell. In each cell, there is a set
  of chromosomes which are strings of DNA and serves as a
  model of the organism. A chromosomes consist of genes
  of blocks of DNA. Each gene encodes a particular pattern.
  Basically, it can be said that each gene encodes a traits.

                                                         A
Fig.                 A
                                                 G
                             G              C
Genome                           T

consisting                            A
                                             A
Of                       T   C
                                  G
                                                     T       C
chromosomes.
ENCODING
There are many ways of representing individual genes.

Binary Encoding
Octal Encoding
Hexadecimal Encoding
Permutation Encoding
Value Encoding
Tree Encoding
BENEFITS OF GENETIC ALGORITHM
Easy to understand.
We always get an answer and the answer gets better
 with time.
Good for noisy environment.
Flexible in forming building blocks for hybrid
 application.
Has substantial history and range of use.
Supports multi-objective optimization.
Modular, separate from application.
APPLICATION OF SOFT
COMPUTING
Consumer appliance like
 AC, Refrigerators, Heaters, Washing machine.
Robotics like Emotional Pet robots.
Food preparation appliances like Rice cookers and
 Microwave.
Game playing like Poker, checker etc.
FUTURE SCOPE
Soft Computing can be extended to include bio-
 informatics aspects.
Fuzzy system can be applied to the construction of
 more advanced intelligent industrial systems.
Soft computing is very effective when it’s applied to
 real world problems that are not able to solved by
 traditional hard computing.
Soft computing enables industrial to be innovative due
 to the characteristics of soft computing:
 tractability, low cost and high machine intelligent
 quotient.
REFERENCES
 Neural Networks, Fuzzy Logic, and Genetic Algorithms Synthesis and
  Application by S. Rajasekaran and G.A. Vijayalakshmi Patel
 L. A. Zadeh, “Fuzzy logic, neural networks and soft computing,” in
  Proc. IEEE Int. Workshop Neuro Fuzzy Control, Muroran, Japan, 1993.
 T. Nitta, “Application of neural networks to home appliances,” in Proc.
  IEEE Int. Joint Conf. Neural Networks, Nagoya, Japan, 1993.
 P.J. Werbos, “Neuro-control and elastic fuzzy logic:
  Capabilities, concepts and application,” IEEE Trans. Ind. Electron., Vol.
  40. 1993.
 Y. Dote and R.G. Hoft, Intelligent Control-Power Electronics Systems.
  Oxford, U.K.: Oxford Univ. Press, 1998.
 L. A. Zadeh, “From computing with numbers to computing with
  words-From manipulation of measurements to manipulation of
  perception,” IEEE Trans. Circuit Syst., Vol. 45, Jan 1999.
Any Questions