Binary Representation of Information

1. chapter8 Binary Representation of Information bit: 0 byte: 0110 11000 "word": 01011100 11101111 00010000 11110000

2. Digital Information (Binary) There are 10 different kinds of people in the world: those who know binary and those who don't. --Anon

3. Digital Information (Binary) Von Neumann Architecture A. CPU; B. RAM; C. I/O; D. Bus What Can Computers Do? • I/O operations • Storage ops. (RAM, disk, disc, ...) • Arithmetic ops. (+, -, *, /, %, ^, ...) • Logic ops. (<, <=, ==, !=, >=, >, AND, OR, ...) ==> Computers are technologically complex but conceptually simple

4. Digital Information (Binary) Pictures of the Tinker Toy computer.How the Tinker Toy computer works.

5. Digital Information Processing Performance Speeds How Fast Are Computers? Two measures of throughput MIPS: 2 ^ 3 ==> 8 FLOPS: 3.14159 ^ 2.718 = 22.45186162Supercomputers: MFLOPS; GFLOPS; TFLOPS; PFLOPS.The Prefixes of the S.I.

6. Digital Information Processing Performance Speeds Q: If a supercomputer can execute 1 GFLOPS, one instruction requires how much time to execute?A: 1 nanosecond. Q: If a supercomputer can execute 1 PFLOPS, one instruction requires how much time to execute?A: ???

7. Information Processing Speeds People MFLOPS: recite 1..1M; 2 sec/recitation; 2Msec = 33,333 min. == 23 days GFLOPS: recite 1..1G; 3 sec/recitation; 3Gsec = 50M min. == 34K days = 100 yrs TFLOPS: recite 1..1T; 6 sec/recitation; 6Tsec = 200K yrs

8. Neurobiology 1011 neurons, each connected to 104 others Switching Speed: 10-3 sec. vs.computer: 10-10 sec. Yet humans are able to make surprisingly complex decisions, surprisingly quickly. (eg) 10-1 sec. for infant to visually recognize its mother

9. Neurobiology the information-processing abilities of biological systems must follow from highly parallel processes distributed over many neurons  Artificial Neural Networks

10. Artificial Intelligence Research: Basic Premise Genus: Information Processing System (IPS) / \ Species: Biological Computers Systems  Both species governed by same principles

11. AI Research Scientific MetaphorsThe heart is a pump The brain is a computer (IPS) Metaphor  “The heart has its reasons of which reason knows nothing.” -- Blaise Pascal

12. Digeratus: Alan Turing During WWII Turing worked at Bletchley Park, Britain's codebreaking centre, & was responsible for German naval cryptanalysis. He devised a number of techniques for breaking German ciphers, including the method of the bombe, an electromechanical machine that could find settings for the Enigma machine.

13. The Turing Test for Intelligence: "Computing machinery and intelligence." (1950) The Turing test is a proposal for a test of a machine's capability to demonstrate intelligence: A human judge engages in a natural language conversation with one human and one machine, each of which try to appear human; if the judge cannot reliably tell which is which, then the machine is said to pass the test.

15. Five Categories of Information • Rover photos of Mars. Category: ? • 100 Kdigits of PI. Category: ? • Clerk's Prolog, Canterbury Tales. Category: ? • Prelude & Fugue in C, J.S. Bach. Category: ? • A statement in a computer program.Category: ?

16. Five Categories of Information Q: Which of the 5 categories is this? 01011100 11101111 00010000 11110000 A: It could be any one of the 5 (eg) How bit maps are used to represent images in computers.

17. Why Do Computers Use Binary? Nine Rungs of the Computer Inferno 1. Physics level. 2. Device Level: Transistors 3. Gate Level: AND, OR PandA = TandF (p. 212) “Logic is the foundation of reasoning, and the foundation of computing. By associating true with presence & False with Absence, we can use the physical world to implement the logical world. This produces Information Technology.”

18. Why Do Computers Use Binary? 4. Machine Level: full adder a water adder flip-flop (stores one bit)