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ADVANCED INTELLIGENT SYSTEMS

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Title: ADVANCED INTELLIGENT SYSTEMS


1
Chapter 13
  • ADVANCED INTELLIGENT SYSTEMS

2
Learning Objectives
  • Understand machine-learning concepts
  • Learn the concepts and applications of case-based
    systems
  • Understand the concepts and applications of
    genetic algorithms
  • Understand fuzzy set theories and their
    applications in designing intelligent systems

3
Learning Objectives
  • Understand the concepts and applications of
    natural language processing (NLP)
  • Learn the concepts, advantages, and limitations
    of voice technologies
  • Learn about integrated intelligent support systems

4
Machine-Learning Techniques
  • Machine-learning concepts and definitions
  • Machine learning
  • The process by which a computer learns from
    experience (e.g., using programs that can learn
    from historical cases)

5
Machine-Learning Techniques
  • Human learning is a combination of many
    complicated cognitive processes including
  • Induction
  • Deduction
  • Analogy
  • Other special procedures related to observing or
    analyzing examples

6
Machine-Learning Techniques
  • How learning relates to intelligent systems
  • Learning systems demonstrate interesting learning
    behaviors
  • AI is not able to learn as well as humans or in
    the same way that humans
  • Machine learning cannot be applied in a creative
    way, although such systems can handle cases to
    which they have never been exposed
  • It is not clear why learning systems succeed or
    fail
  • A common thread running through most AI
    approaches to learning is the manipulation of
    symbols rather than numeric information

7
Machine-Learning Techniques
  • Machine-learning methods
  • Supervised learning
  • A method of training artificial neural networks
    in which sample cases are shown to the network as
    input and the weights are adjusted to minimize
    the error in its outputs
  • Unsupervised learning
  • A method of training artificial neural networks
    in which only input stimuli are shown to the
    network, which is self-organizing

8
Machine-Learning Techniques
9
Machine-Learning Techniques
Machine-learning methods and algorithms
  • Inductive learning
  • Case-based reasoning
  • Neural computing
  • Genetic algorithms
  • Natural language processing (NLP)
  • Cluster analysis
  • Statistical methods
  • Explanation-based learning
  • A machine learning approach that assumes that
    there is enough existing theory to rationalize
    why one instance is or is not a prototypical
    member of a class

10
Case-Based Reasoning (CBR)
  • Case-based reasoning (CBR)
  • A methodology in which knowledge and/or
    inferences are derived from historical cases

11
Case-Based Reasoning (CBR)
  • Analogical reasoning
  • Determining the outcome of a problem with the
    use of analogies. A procedure for drawing
    conclusions about a problem by using past
    experience
  • Inductive learning
  • A machine learning approach in which rules are
    inferred from facts or data

12
Case-Based Reasoning (CBR)
  • The basic idea and process of CBR
  • Four-step process
  • Retrieve
  • Reuse
  • Revise
  • Retain

13
Case-Based Reasoning (CBR)
  • Definition and concepts of cases in CBR
  • Ossified cases
  • Cases that have been analyzed and have no
    further value
  • Paradigmatic cases
  • A case that is unique that can be maintained to
    derive new knowledge for the future

14
Case-Based Reasoning (CBR)
  • Definition and concepts of cases in CBR
  • Stories
  • Cases with rich information and episodes.
    Lessons may be derived from this kind of cases in
    a case base

15
Case-Based Reasoning (CBR)
16
Case-Based Reasoning (CBR)
  • Benefits and usability of CBR
  • CBR makes learning much easier and the
    recommendation more sensible

17
Case-Based Reasoning (CBR)
  • Advantages of using CBR
  • Knowledge acquisition is improved.
  • System development time is faster
  • Existing data and knowledge are leveraged
  • Complete formalized domain knowledge is not
    required
  • Experts feel better discussing concrete cases
  • Explanation becomes easier
  • Acquisition of new cases is easy
  • Learning can occur from both successes and
    failures

18
Case-Based Reasoning (CBR)
19
Case-Based Reasoning (CBR)
  • Uses, issues, and applications of CBR
  • Applications
  • CBR in electronic commerce
  • WWW and information search
  • Planning and control
  • Design
  • Reuse
  • Diagnosis
  • Reasoning

20
Case-Based Reasoning (CBR)
  • Uses, issues, and applications of CBR
  • Implementation issues for designers
  • What makes up a case? How can we represent case
    memory?
  • Automatic case-adaptation rules can be very
    complex
  • How is memory organized? What are the indexing
    rules?
  • The quality of the results is heavily dependent
    on the indexes used

21
Case-Based Reasoning (CBR)
  • Implementation issues for designers
  • How does memory function in relevant information
    retrieval?
  • How can we perform efficient searching (i.e.,
    knowledge navigation) of the cases?
  • How can we organize the cases?
  • How can we design the distributed storage of
    cases?
  • How can we adapt old solutions to new problems?
    Can we simply adapt the memory for efficient
    querying, depending on context? What are the
    similarity metrics and the modification rules?

22
Case-Based Reasoning (CBR)
  • Implementation issues for designers
  • How can we factor errors out of the original
    cases?
  • How can we learn from mistakes? That is, how can
    we repair and update the case base?
  • The case base may need to be expanded as the
    domain model evolves, yet much analysis of the
    domain may be postponed.
  • How can we integrate CBR with other knowledge
    representations and inferencing mechanisms?
  • Are there better pattern-matching methods than
    the ones we currently use?
  • Are there alternative retrieval systems that
    match the CBR schema?

23
Case-Based Reasoning (CBR)
  • Success factors for CBR systems
  • Determine specific business objectives
  • Understand your end users and customers
  • Design the system appropriately
  • Plan an ongoing knowledge-management process
  • Establish achievable returns on investment (ROI)
    and measurable metrics
  • Plan and execute a customer-access strategy
  • Expand knowledge generation and access across the
    enterprise

24
Genetic Algorithm Fundamentals
  • Genetic algorithms (GAs)
  • Software programs that learn in an evolutionary
    manner similar to the way biological systems
    evolve

25
Genetic Algorithm Fundamentals
  • Genetic algorithm process and terminology
  • Chromosome
  • A candidate solution for a genetic algorithm
  • Reproduction
  • The creation of new generations of improved
    solutions with the use of a genetic algorithm

26
Genetic Algorithm Fundamentals
  • Genetic algorithm process and terminology
  • Crossover
  • The combining of parts of two superior solutions
    by a genetic algorithm in an attempt to produce
    an even better solution
  • Mutation
  • A genetic operator that causes a random change
    in a potential solution

27
Genetic Algorithm Fundamentals
28
Genetic Algorithm Fundamentals
29
Genetic Algorithm Fundamentals
  • A few parameters must be set for the genetic
    algorithm
  • Number of initial solutions to generate
  • Number of offspring to generate
  • Number of parents and offspring to keep for the
    next generation
  • Mutation probability (very low)
  • Probability distribution of crossover point
    occurrence

30
Genetic Algorithm Fundamentals
  • Limitations of genetic algorithms
  • Not all problems can be framed in the
    mathematical manner that genetic algorithms
    demand
  • Development of a genetic algorithm and
    interpretation of the results requires an expert
    who has both the programming and
    statistical/mathematical skills demanded by the
    genetic algorithm technology in use
  • In some situations, the genes from a few
    comparatively highly fit (but not optimal)
    individuals may come to dominate the population,
    causing it to converge on a local maximum

31
Genetic Algorithm Fundamentals
  • Limitations of genetic algorithms
  • Most genetic algorithms rely on random number
    generators that produce different results each
    time the model runs
  • Locating good variables that work for a
    particular problem is difficult
  • Selecting methods by which to evolve the system
    requires thought and evaluation

32
Developing Genetic Algorithm Applications
  • GAs are a type of machine learning for
    representing and solving complex problems

33
Developing Genetic Algorithm Applications
Applications of GAs include
  • Dynamic process control
  • Induction of optimization of rules
  • Discovery of new connectivity topologies (e.g.,
    neural computing connections, i.e., neural
    network design)
  • Simulation of biological models of behavior and
    evolution
  • Complex design of engineering structures
  • Pattern recognition
  • Scheduling
  • Transportation and routing
  • Layout and circuit design
  • Telecommunication
  • Graph-based problems

34
Fuzzy Logic Fundamentals
  • Fuzzy logic
  • Logically consistent ways of reasoning that can
    cope with uncertain or partial information
    characteristic of human thinking and many expert
    systems.
  • Fuzzy sets
  • A set theory approach in which set membership is
    less precise than having objects strictly in or
    out of the set

35
Fuzzy Logic Fundamentals
  • Fuzzy Set for a Tall Person
  • If we survey people to define the minimum height
    a person must attain before being a tall man, the
    answer could be ranged from 5 to 7 feet(1 foot
    is about 30cm, 1 inch is about 2.54cm). The
    distribution of answers might look like this

Height Proportion voted for
510 0.05
511 0.10
6 0.60
6.1 0.15
6.2 0.10
36
Fuzzy Logic Fundamentals
  • Fuzzy Set for a Tall Person
  • Suppose Jacks height is 6 feet. From probability
    theory, we can use the cumulative probability
    distribution and say there is a 75 chance that
    Jack is tall.
  • In fuzzy logic, we say that Jacks degree of
    membership in the set of tall people is 0.75.
  • The difference in probability term, Jack is
    perceived as either tall or not tall. But we
    could not completely sure whether he is tall. In
    fuzzy logic, we agree that Jack is more or less
    tall. We can assign a membership function to show
    the relationship of Jack to the set of tall
    people (ie. The fuzzy logic set)
  • ltJack, 0.75 Tallgt
  • This can be repressed in a knowledge-based
    systems as Jack is tall (CF0.75).
  • An important difference from probability theory
    is that related memberships in fuzzy sets do not
    have to total 1.

37
Fuzzy Logic Fundamentals
  • Fuzzy Set for a Tall Person
  • The statement Jack is short (CF0.1) indicate
    that the combination is only 0.90. In probability
    theory, if the probability that Jack is tall is
    0.75, then the probability that he is not tall
    (i.e., if only two events, he is short) must be
    0.25.
  • In contrast to certainty factors that includes
    two values (e.g., the degree of belief or
    disbelief), fuzzy sets use a spectrum of possible
    values called belief functions. We express our
    belief that a particular item belongs to a set
    through a membership function, as shown in Figure
    13.7.
  • At a height of 69 inches, a person starts to be
    considered tall, and at 74 inches, he or she is
    definitely tall. Between 69 and 74 inches, the
    persons membership function value varies from 0
    to 1. Likewise, a person has a membership
    function value in the set of short people and
    medium-height people, depending on his or her
    height. The medium range spans both the short and
    tall ranges, so a person has a belief of
    potentially being a member of more than one fuzzy
    set at a time.
  • This is a critical strength of fuzzy sets no
    crispness.

38
Fuzzy Logic Fundamentals
39
Fuzzy Logic Fundamentals
  • Fuzzy logic applications in manufacturing and
    management
  • Selection of stocks to purchase (e.g., the
    Japanese Nikkei stock exchange)
  • Retrieval of data (because fuzzy logic can find
    data quickly)
  • Inspection of beverage cans for printing defects
  • Matching of golf clubs to customers swings
  • Risk assessment
  • Control of the amount of oxygen in cement kilns
  • Accuracy and speed increases in industrial
    quality-control applications
  • Sorting problems in multidimensional spaces

40
Fuzzy Logic Fundamentals
  • Fuzzy logic applications in manufacturing and
    management
  • Enhancement of models involving queuing (i.e.,
    waiting lines)
  • Managerial decision support applications
  • Project selection
  • Environmental control building
  • Control of the motion of trains
  • Paper mill automation
  • Space shuttle vehicle orbiting
  • Regulation of water temperature in shower heads

41
Natural Language Processing (NLP)
  • Natural language processing (NLP)  
  • Using a natural language processor to interface
    with a computer-based system
  • Two types of NLP
  • Natural language understanding
  • Natural language generation

42
Natural Language Processing (NLP)
  • Some problems that make NLP difficult
  • Word boundary detection
  • Word sense disambiguation
  • Syntactic ambiguity
  • Imperfect or irregular input
  • Speech acts and plans

43
Natural Language Processing (NLP)
  • The current NLP technology
  • Search and information retrieval
  • A person enters a certain phrase, word, or
    sentence on which to search the Internet or some
    database, and NLP is then used to construct the
    best query possible

44
Natural Language Processing (NLP)
  • Applications of NLP
  • Humancomputer interfaces
  • Abstracting and summarizing text
  • Analyzing grammar
  • Understanding speech

45
Natural Language Processing (NLP)
  • Applications of NLP
  • Front ends for other software packagesquerying a
    database that allows the user to operate the
    applications programs with everyday language
  • Text mining
  • FAQs and query answering

46
Natural Language Processing (NLP)
  • Machine translation
  • Translation of content to other languages
  • Criteria used to assess machine translation
  • Intelligibility
  • Accuracy
  • Speed

47
Voice Technologies
  • Voice technologies fall into three broad
    categories
  • Voice (or speech) recognition
  • Voice (or speech) understanding
  • Text-to-voice (or voice synthesis)

48
Voice Technologies
  • Voice (speech) recognition
  • Translation of the human voice into individual
    words and sentences understandable by a computer
  • Speech understanding
  • An area of AI research that attempts to allow
    computers to recognize words or phrases of human
    speech

49
Voice Technologies
  • Advantages of voice technologies
  • Ease of access
  • Speed
  • Manual freedom
  • Remote access
  • Accuracy
  • Communicating while driving
  • Quick selection
  • Security
  • Cost benefit

50
Voice Technologies
  • Limitations of speech recognition and
    understanding
  • Inability to recognize long sentences, or the
    excessive length of time needed to accomplish
    that understanding
  • High cost
  • Speech may need to be combined with keyboard
    entry, which slows communication

51
Voice Technologies
  • Voice synthesis
  • The technology by which computers convert
    text-to-voice (speak)
  • A text-to-speech system is composed of two parts
  • Front end takes input in the form of text and
    outputs a symbolic linguistic representation
  • Back end takes the symbolic linguistic
    representation as input and outputs the
    synthesized speech waveform

52
Voice Technologies
  • Voice technology applications
  • Call center
  • Contact of customer care center
  • Computer/telephone integration (CTI)
  • Interactive voice response (IVR)
  • Voice portal
  • Voice over IP (VoIP)

53
Voice Technologies
  • Voice portals
  • Web sites, usually portals, with audio interfaces

54
Intelligent Systems over the Internet
  • Web-Based Intelligent Systems

55
Intelligent Systems over the Internet
  • Web-Based Intelligent Systems
  • Small systems that perform very specific tasks
    are often called agents
  • Information agent take a request and navigate to
    the appropriate page on a Web site, locate the
    required information, and return it as an XML
    document for processing by another agent
  • Monitoring agents are built on top of the
    information agent to keep track of previously
    returned results
  • Recommender or recommendation agents assist in
    customization and personalization services that
    are critical to maintaining good customer
    relationships

56
Intelligent Systems over the Internet
  • Intelligent Agents An Overview
  • Intelligent agent (IA) An expert or
    knowledge-based system embedded in computer-based
    information systems (or their components) to make
    them smarter
  • The term agent is derived from the concept of
    agency, referring to employing someone to act on
    your behalf
  • Types of agents
  • Software agents
  • Wizards
  • Software daemons
  • Softbots Intelligent software agents an
    abbreviation of robots. Usually used as part of
    another term, as in knowbots, softbots, or
    shopbots

57
Intelligent Systems over the Internet
  • Intelligent Agents An Overview
  • Features of intelligent agents
  • Reactivity Agents perceive their environment and
    respond in a timely fashion to changes that occur
    in it
  • Proactiveness Agents are able to exhibit
    goal-directed behavior by taking initiative
  • Social ability
  • Autonomy
  • Intelligence levels
  • Level 0Agents retrieve documents for a user
    under straight orders
  • Level 1Agents provide a user-initiated searching
    facility for finding relevant Web pages
  • Level 2Agents maintain users profiles
  • Level 3Agents have a learning and deductive
    component to help a user who cannot formalize a
    query or specify a target for a search

58
Intelligent Systems over the Internet
  • Intelligent Agents An Overview
  • Components of an agent
  • Owner
  • Author
  • Owner
  • Goal
  • Subject description
  • Creation and duration
  • Background
  • Intelligent subsystem

59
Intelligent Systems over the Internet
  • Classification and Types of Intelligent Agents

60
Intelligent Systems over the Internet
  • DSS Agents and Multiagents
  • Five types of DSS agents
  • Data monitoring
  • Data gathering
  • Modeling
  • Domain managing
  • Preference learning
  • Multiagent system
  • A system with multiple cooperating software
    agents
  • Distributed artificial intelligence (DAI)
  • A multiple-agent system for problem solving.
    Splitting of a problem into multiple cooperating
    systems in deriving a solution

61
Intelligent Systems over the Internet
  • DSS Agents and Multiagents

62
Intelligent Systems over the Internet
  • The Semantic Web Representing Knowledge for
    Intelligent Agents

63
Intelligent Systems over the Internet
  • Web-Based Recommendation Systems
  • A major application of intelligent systems in
    e-commerce is to recommend products to customers
  • The major motivation for using recommendation
    agents is that personalization is a major trend
    in marketing and customer services
  • Recommendation systems (agents)
  • A computer system that can suggest new items to a
    user based on his revealed preference. It may be
    content-based or collaborative filtering to
    suggest items that match the preference of the
    user. An example is that Amazon.com's function of
    Other people bought this book also bought . . .
    function
  • Collaborative filtering A method for generating
    recommendations from user profile. It uses
    preferences of other users of similar behavior to
    predict the preference of the particular user.

64
Intelligent Systems over the Internet
  • Web-Based Recommendation Systems
  • Content-based filtering A method that recommends
    items for the user based on the description of
    previously evaluated items and information
    available from the content (such as keywords)
  • Demographic filtering
  • A method that uses the demographic data of the
    user to determine which item may be appropriate
    for recommendation.

65
Intelligent Systems over the Internet
  • Web-Based Recommendation Systems

66
Intelligent Systems over the Internet
  • Web-Based Recommendation Systems

67
Developing Integrated Advanced Systems
  • Fuzzy neural networks
  • Fuzzification
  • A process that converts an accurate number into
    a fuzzy description, such as converting from an
    exact age into young or old
  • Defuzzification
  • Creating a crisp solution from a fuzzy logic
    solution

68
Developing Integrated Advanced Systems
69
Developing Integrated Advanced Systems
70
Developing Integrated Advanced Systems
  • Genetic algorithms and neural networks
  • The genetic learning method can perform rule
    discovery in large databases, with the rules fed
    into a conventional ES or some other intelligent
    system
  • To integrate genetic algorithms with neural
    network models use a genetic algorithm to search
    for potential weights associated with network
    connections
  • A good genetic learning method can significantly
    reduce the time and effort needed to find the
    optimal neural network model
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