Fuzzy Logic and its ApplicationsBySwaroop.M.R2SD07CS106Under the Guidance ofTGS
ContentsIntroduction to Fuzzy LogicDefinition , Description with example. Fuzzy Logic  - RepresentationMembership Functions : ExamplesFuzzy Sets  Information Flow in Fuzzy SystemsApplications Benefits ConclusionReferences
1.IntroductionIn this seminar the presentation includes the definition ,essence and application of Fuzzy Logic .Fuzzy logic is a main tool for designing a intelligent / ubiquitous /context aware systems.Fuzzy logic can represent multiple states of a given entity like temperature (low, medium, normal, high, very high, etc)
1a.Fuzzy Logic – A DefinitionFuzzy logic provides a method to formalize reasoning when dealing with vague terms. Traditional computing requires finite precision which is not always possible in real world scenarios.  Not every decision is either true or false, or as with Boolean logic either 0 or 1.  Fuzzy logic allows for membership functions, or degrees of truthfulness and falsehoods.  Or as with Boolean logic, not only 0 and 1 but all the numbers that fall in between.
 WHAT IS FUZZY LOGIC?Definition of fuzzy
Fuzzy – “not clear, distinct, or precise; blurred”
Definition of fuzzy logic
A form of knowledge representation suitable for notions that cannot be defined precisely, but which depend upon their contexts.        1b.   FUZZY LOGIC REPRESENTATIONSlowestFor every problem must represent in terms of fuzzy sets.[ 0.0 – 0.25 ]Slow[ 0.25 – 0.50 ]Fast[ 0.50 – 0.75 ]Fastest[ 0.75 – 1.00 ]
                FUZZY LOGIC REPRESENTATION CONT.SlowestFastestSlowFastfloat speed; get the speed if ((speed >= 0.0)&&(speed < 0.25)) {	//  speed is slowest} else if ((speed >= 0.25)&&(speed < 0.5)) {	//  speed is slow}else if ((speed >= 0.5)&&(speed < 0.75)) {	//  speed is fast}else // speed >= 0.75 && speed < 1.0 {	//  speed is fastest}
2.Membership Functions (MFs)Linguistic terms – Fuzzy Terms called as Linguistic Terms.Definition-These are the input or output variables of the system whose values are words or sentences from a natural language instead of numerical values.Characteristics of MFs:Subjective measuresNot probability functions
Membership FunctionsDefinition-Membership functions are used in the fuzzification and defuzzification steps of a given statement, to map the non-fuzzy input values to fuzzy linguistic terms and vice-versa.A membership function is used to qualify a linguistic term.
Types of Membership FunctionsSingleton Functions. – Only for 2 possibility		Ex- inside , outsideTrapezoidal Function.- More than 2 possibility		Ex – Low , Medium ,High
3.Fuzzy SetsFormal definition:A fuzzy set A in X is expressed as a set of ordered pairs:A = {(x, Ma (x)) , x ϵX }Membershipfunction(MF)Universe oruniverse of discourseFuzzy setA fuzzy set is totally characterized by amembership function (MF).
Fuzzy Set OperationsMax – OR  ( ex – Max (1 ,2) =2 )Min  – AND ( ex – Min (1,2) = 1 )PROD  – AND  ( ex – PROD (1,2) = 1)
4.Information flow in Fuzzy System
ExampleINPUTFuzzificationRule AssociationDefuzzificationTemp = 10 CTemp = LowTemp = HighTemp = 25
Fuzzy SetsSets with fuzzy boundariesA = Set of tall peopleXXFuzzy set ACrisp set AMembershipfunction1.01.00.90.5YY5.105.10HeightHeight6.2
              6.BENEFITS OF USING FUZZY LOGIC
FUZZY LOGIC IN OTHER FIELDS  Business
  Hybrid Modelling
  Expert SystemsHow is Fuzzy Logic Used?Fuzzy MathematicsFuzzy Numbers – almost 5, or more than 50
Fuzzy Geometry – Almost Straight Lines
Fuzzy Algebra – Not quite a parabola
Fuzzy Calculus
Fuzzy Graphs – based on fuzzy pointsGeneralFuzzified ApplicationsQuality AssuranceError DiagnosticsControl TheoryPattern Recognition

Swaroop.m.r

  • 1.
    Fuzzy Logic andits ApplicationsBySwaroop.M.R2SD07CS106Under the Guidance ofTGS
  • 2.
    ContentsIntroduction to FuzzyLogicDefinition , Description with example. Fuzzy Logic - RepresentationMembership Functions : ExamplesFuzzy Sets Information Flow in Fuzzy SystemsApplications Benefits ConclusionReferences
  • 3.
    1.IntroductionIn this seminarthe presentation includes the definition ,essence and application of Fuzzy Logic .Fuzzy logic is a main tool for designing a intelligent / ubiquitous /context aware systems.Fuzzy logic can represent multiple states of a given entity like temperature (low, medium, normal, high, very high, etc)
  • 4.
    1a.Fuzzy Logic –A DefinitionFuzzy logic provides a method to formalize reasoning when dealing with vague terms. Traditional computing requires finite precision which is not always possible in real world scenarios. Not every decision is either true or false, or as with Boolean logic either 0 or 1. Fuzzy logic allows for membership functions, or degrees of truthfulness and falsehoods. Or as with Boolean logic, not only 0 and 1 but all the numbers that fall in between.
  • 5.
    WHAT ISFUZZY LOGIC?Definition of fuzzy
  • 6.
    Fuzzy – “notclear, distinct, or precise; blurred”
  • 7.
  • 8.
    A form ofknowledge representation suitable for notions that cannot be defined precisely, but which depend upon their contexts. 1b. FUZZY LOGIC REPRESENTATIONSlowestFor every problem must represent in terms of fuzzy sets.[ 0.0 – 0.25 ]Slow[ 0.25 – 0.50 ]Fast[ 0.50 – 0.75 ]Fastest[ 0.75 – 1.00 ]
  • 9.
    FUZZY LOGIC REPRESENTATION CONT.SlowestFastestSlowFastfloat speed; get the speed if ((speed >= 0.0)&&(speed < 0.25)) { // speed is slowest} else if ((speed >= 0.25)&&(speed < 0.5)) { // speed is slow}else if ((speed >= 0.5)&&(speed < 0.75)) { // speed is fast}else // speed >= 0.75 && speed < 1.0 { // speed is fastest}
  • 10.
    2.Membership Functions (MFs)Linguisticterms – Fuzzy Terms called as Linguistic Terms.Definition-These are the input or output variables of the system whose values are words or sentences from a natural language instead of numerical values.Characteristics of MFs:Subjective measuresNot probability functions
  • 11.
    Membership FunctionsDefinition-Membership functionsare used in the fuzzification and defuzzification steps of a given statement, to map the non-fuzzy input values to fuzzy linguistic terms and vice-versa.A membership function is used to qualify a linguistic term.
  • 12.
    Types of MembershipFunctionsSingleton Functions. – Only for 2 possibility Ex- inside , outsideTrapezoidal Function.- More than 2 possibility Ex – Low , Medium ,High
  • 13.
    3.Fuzzy SetsFormal definition:Afuzzy set A in X is expressed as a set of ordered pairs:A = {(x, Ma (x)) , x ϵX }Membershipfunction(MF)Universe oruniverse of discourseFuzzy setA fuzzy set is totally characterized by amembership function (MF).
  • 14.
    Fuzzy Set OperationsMax– OR ( ex – Max (1 ,2) =2 )Min – AND ( ex – Min (1,2) = 1 )PROD – AND ( ex – PROD (1,2) = 1)
  • 15.
  • 16.
  • 17.
    Fuzzy SetsSets withfuzzy boundariesA = Set of tall peopleXXFuzzy set ACrisp set AMembershipfunction1.01.00.90.5YY5.105.10HeightHeight6.2
  • 18.
    6.BENEFITS OF USING FUZZY LOGIC
  • 19.
    FUZZY LOGIC INOTHER FIELDS Business
  • 20.
    HybridModelling
  • 21.
    ExpertSystemsHow is Fuzzy Logic Used?Fuzzy MathematicsFuzzy Numbers – almost 5, or more than 50
  • 22.
    Fuzzy Geometry –Almost Straight Lines
  • 23.
    Fuzzy Algebra –Not quite a parabola
  • 24.
  • 25.
    Fuzzy Graphs –based on fuzzy pointsGeneralFuzzified ApplicationsQuality AssuranceError DiagnosticsControl TheoryPattern Recognition