trí tuệ nhân tạo cao hoàng trứ chương ter1 introduction sinhvienzone com

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Introduction

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• A brief history of AI

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• The foundations of AI

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• What is AI?

• The state of the art

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• Introductory problems

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What is AI?

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What is AI?

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• Intelligence: “ability to learn, understand and think”

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(Oxford dictionary)

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What is AI?

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Acting rationally

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Acting humanly

Thinking rationally

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Thinking humanly

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Acting Humanly: The Turing Test

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• Alan Mathison Turing (1912-1954)

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Turing Award

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• A.M. Turing Award

ACM's most prestigious technical award is accompanied by a

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prize of $250,000. It is given to an individual selected for

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contributions of a technical nature made to the computing

community. The contributions should be of lasting and major

technical importance to the computer field. Financial support of

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the Turing Award is provided by the Intel Corporation and
Google Inc.

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Turing Award
2000 Yao, Andrew Chi-Chih

1988 Sutherland, Ivan

1999 Brooks, Frederick P.

1987 Cocke, John

2006 Allen, Frances E

1998 Gray, Jim

1986 Hopcroft, John E
1986 Tarjan, Robert E

2004 Cerf, Vinton
2004 Kahn, Robert E

1995 Blum, Manuel

2002 Adleman, Leonard M.
2002 Rivest, Ronald L.
2002 Shamir, Adi
2001 Dahl, Ole-Johan
2001 Nygaard, Kristen

1994 Feigenbaum, Edward

199 Reddy, Raj

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2003 Kay, Alan

1993 Hartmanis, Juris
1993 Stearns, Richard E

1992 Lampson, Butler W.

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1991 Milner, A J

1990 Corbato, Fernando J.
1989 Kahan, William

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1985 Karp, Richard M

1974 Knuth, Donald E.

1984 Wirth, Niklaus E

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1996 Pnueli, Amir

1975 Newell, Allen
1975 Simon, Herbert A.

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1997 Engelbart, Douglas

1976 Rabin, Michael O.
1976 Scott, Dana S

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2005 Naur, Peter

1977 Backus, John

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2007 Clarke, Edmund M
2007 Emerson, E Allen
2007 Sifakis, Joseph

1983 Ritchie, Dennis M.
1983 Thompson, Kenneth Lane
1982 Cook, Stephen A
1981 Codd, Edgar F.

1980 Hoare, C. Antony R.
1979 Iverson, Kenneth E.
1978 Floyd, Robert W

1973 Bachman, Charles W.
1972 Dijkstra, E. W.
1971 McCarthy, John
1970 Wilkinson, J. H.
1969 Minsky, Marvin
1968 Hamming, Richard
1967 Wilkes, Maurice V.
1966 Perlis, A. J.

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Acting Humanly: The Turing Test

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• “Computing Machinery and Intelligence” (1950)

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Acting Humanly: The Turing Test

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Imitation Game

AI System

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Human Interrogator

Human

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Acting Humanly: The Turing Test

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• Predicted that by 2000, a machine might have a 30%

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chance of fooling a lay person for 5 minutes.

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following 50 years.

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• Anticipated all major arguments against AI in
• Suggested major components of AI: knowledge,

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reasoning, language, understanding, learning.

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Thinking Humanly: Cognitive Modelling

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• Not content to have a program correctly solving a

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problem.

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More concerned with comparing its reasoning steps
to traces of human solving the same problem.

• Requires testable theories of the workings of the

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human mind: cognitive science.

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Thinking Rationally: Laws of Thought

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• Aristotle was one of the first to attempt to codify “right

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thinking”, i.e., irrefutable reasoning processes.

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• Formal logic provides a precise notation and rules for
• Obstacles:

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representing and reasoning with all kinds of things in
the world.

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− Representation of informal knowledge.

− Computational complexity and resources.
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Acting Rationally

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• Acting so as to achieve one’s goals, given one’s

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beliefs.

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• Does not necessarily involve thinking.
• Advantages:

− More general than the “laws of thought” approach.

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− More amenable to scientific development than humanbased approaches.

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• Philosophy (423 BC − present):

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The Foundations of AI

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− Logic, methods of reasoning.

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− Mind as a physical system.
− Foundations of learning, language, and rationality.

• Mathematics (c.800 − present):

− Formal representation and proof.

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− Algorithms, computation, decidability, tractability.
− Probability.

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• Psychology (1879 − present):

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The Foundations of AI

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− Adaptation.

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− Phenomena of perception and motor control.
− Experimental techniques.

• Linguistics (1957 − present):
− Knowledge representation.

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− Grammar.

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A Brief History of AI

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• The gestation of AI (1943 − 1956):

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− 1943: McCulloch & Pitts: Boolean circuit model of brain.

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− 1950: Turing’s “Computing Machinery and Intelligence”.
− 1956: McCarthy’s name “Artificial Intelligence” adopted.

• Early enthusiasm, great expectations (1952 − 1969):

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− Early successful AI programs: Samuel’s checkers,
Newell & Simon’s Logic Theorist, Gelernter’s Geometry
Theorem Prover.
− Robinson’s complete algorithm for logical reasoning.

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• A dose of reality (1966 − 1974):

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A Brief History of AI

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− AI discovered computational complexity.

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− Neural network research almost disappeared after
Minsky & Papert’s book in 1969.

• Knowledge-based systems (1969 − 1979):
− 1969: DENDRAL by Buchanan et al..

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− 1976: MYCIN by Shortliffle.
− 1979: PROSPECTOR by Duda et al..

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CSE Faculty - HCMUT

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A Brief History of AI

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• AI becomes an industry (1980 − 1988):

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− Expert systems industry booms.

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− 1981: Japan’s 10-year Fifth Generation project.

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• The return of NNs and novel AI (1986 − present):

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− Mid 80’s: Back-propagation learning algorithm reinvented.
− Expert systems industry busts.
− 1988: Resurgence of probability.
− 1988: Novel AI (ALife, GAs, Soft Computing, …).
− 1995: Agents everywhere.
− 2003: Human-level AI back on the agenda.

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The State of the Art

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Expert system controls a spacecraft.

Robot can walk on stairs and hold a cup of water.
Language translation for webpages.

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recognition.

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• Computer beats human in a chess game.
• Computer-human conversation using speech

Home appliances use fuzzy logic.
......

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CSE Faculty - HCMUT
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Introductory Problem: Tic-Tac-Toe

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Introductory Problem: Tic-Tac-Toe

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Program 1:

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1. View the vector as a ternary number. Convert it to a
decimal number.
2. Use the computed number as an index into
Move-Table and access the vector stored there.

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3. Set the new board to that vector.

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CSE Faculty - HCMUT
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Introductory Problem: Tic-Tac-Toe

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Comments:

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1. A lot of space to store the Move-Table.

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2. A lot of work to specify all the entries in the
Move-Table.

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3. Difficult to extend.

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Introductory Problem: Tic-Tac-Toe

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1 2 3
4 5 6
7 8 9

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Introductory Problem: Tic-Tac-Toe
Go(1)
If Board[5] is blank, Go(5), else Go(1)
If Board[9] is blank, Go(9), else Go(3)
If Posswin(X) ≠ 0, then Go(Posswin(X))

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Turn = 1
Turn = 2
Turn = 3
Turn = 4
.......

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Program 2:

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Introductory Problem: Tic-Tac-Toe

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Comments:

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1. Not efficient in time, as it has to check several
conditions before making each move.
2. Easier to understand the program’s strategy.

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3. Hard to generalize.

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