Binary Representation of...
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Digital Information (Binary)
Thereare10differentkindsofpeopleintheworld:thosewhoknowbinaryandthosewhodon't.--Anon
Digital Information (Binary)
Von Neumann Architecture A. CPU; B. RAM; C. I/O; D. Bus
What Can Computers Do?1. I/O operations2. Storage ops. (RAM, disk, disc, ...)3. Arithmetic ops. (+, -, *, /, %, ^, ...) 4. Logic ops. (<, <=, ==, !=, >=, >, AND, OR, ...)
==> Computers are technologically complex but conceptually simple
Digital Information (Binary)
Pictures of the Tinker Toy computer.
How the Tinker Toy computer works.
Digital Information Processing Performance Speeds
How Fast Are Computers?
Two measures of throughput
MIPS: 2 ^ 3 ==> 8FLOPS: 3.14159 ^ 2.718 =
22.45186162
Supercomputers: MFLOPS; GFLOPS; TFLOPS; PFLOPS.
The Prefixes of the S.I.
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: ???
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
Five Categories of Information
1. Rover photos of Mars. Category: ? 2. 100 Kdigits of PI. Category: ?3. Clerk's Prolog, Canterbury Tales.
Category: ?4. Prelude & Fugue in C, J.S. Bach.
Category: ?5. A statement in a computer program.
Category: ?
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.
Why Do Computers Use Binary?
Nine Rungs of the Computer Inferno
1. Physics level.2. Device Level: Transistors3. Gate Level: AND, OR
PandA = TandF
“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.”
Why Do Computers Use Binary?
4. Machine Level:
=> full adder
(eg) a water adder device-level components = ???
=> flip-flop (stores one bit)
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
Neurobiology
the information-processing abilities of biological systems must follow from highly parallel processes distributed over many neurons
Artificial Neural Networks
Artificial Intelligence Research: Basic Premise
Genus: Information Processing System (IPS) / \Species: Biological Computers Systems
Both species governed by same principles
AI Research
Scientific Metaphors
The heart is a pump
The brain is a computer (IPS)
Metaphor “The heart has its reasons of which reason knows nothing.”
-- Blaise Pascal
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.
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.
Turing Test for Intelligence:The Simulation Game
Alan Turing's 1950 paper “Computing Machinery and Intelligence” has become one of the most cited in philosophical literature.
In it, Turing described an 'imitation game:' a human interrogator using a computer terminal connected to two additional, unseen, terminals. At one of the "unseen" terminals is a human; at the other is a piece of computer software written to act and respond as if it were human.
The Imitation Game
If the interrogator can not distinguish them by questioning, then it is reasonable to call the computer intelligent
We judge other people's intelligence from external observation in just this way
The Imitation Game
1950: Turing predicted that within 50 years a computer would pass the test
1991: Hugh Loebner started the annual Loebner Prize Contest
Turing Test Questions
Bot or not?
CAPTCHA "Completely Automated Public Turing test to tell Computers and Humans Apart."
As a result, Alan Turing's name comes into an explanation by the Post Office of: Why do I have to type in a code...