Difference between revisions of "CSC103: DT's Notes 1"
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So, in summary, we start seeing that computing, at least the medium chosen for where the computation takes place can be varied, and does not have to be silicon. Indeed, there exist many examples of computation devices that do not use electronics in silicon and can perform quite complex computation. In consequence, we should also be ready to find that new computers in ten, twenty or thirty years will not use semiconductors made of silicon, and may not use electrons to carry information that is controlled by transistors. In fact, it is highly probable that they won't [http://en.wikipedia.org/wiki/Predictions_made_by_Ray_Kurzweil]. | So, in summary, we start seeing that computing, at least the medium chosen for where the computation takes place can be varied, and does not have to be silicon. Indeed, there exist many examples of computation devices that do not use electronics in silicon and can perform quite complex computation. In consequence, we should also be ready to find that new computers in ten, twenty or thirty years will not use semiconductors made of silicon, and may not use electrons to carry information that is controlled by transistors. In fact, it is highly probable that they won't [http://en.wikipedia.org/wiki/Predictions_made_by_Ray_Kurzweil]. | ||
| − | === | + | ===Boolean Algebra=== |
While the technology used in creating today's computer is the result of an evolution and choices driven by economic factors and scientific discoveries, among others, one thing we can be sure of is that whatever computing machine we devise and use to perform calculations, that machine will have to use rules of mathematics. It does not matter what technology we use to compute 2 + 2. The computer must follow strict rules and implement basic mathematical rules in the way it treats information. | While the technology used in creating today's computer is the result of an evolution and choices driven by economic factors and scientific discoveries, among others, one thing we can be sure of is that whatever computing machine we devise and use to perform calculations, that machine will have to use rules of mathematics. It does not matter what technology we use to compute 2 + 2. The computer must follow strict rules and implement basic mathematical rules in the way it treats information. | ||
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Below are some questions for you to figure out: | Below are some questions for you to figure out: | ||
;Question 1 | ;Question 1 | ||
| − | : Which row of the table would | + | : Which row of the table would corresponds to a container of Ben and Jerry's vanilla ice cream? Would our friend like it? |
;Question 2 | ;Question 2 | ||
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;Question 3 | ;Question 3 | ||
| − | : Assume that our friend has a younger brother with a different boolean equation for ice cream. His equation is ( ('''not''' choc) '''and''' ''fruit'') and ( ''HG'' or ( not ''HG'' ) ). Give an example of several ice cream flavors and makers the brother will like. | + | : Assume that our friend has a younger brother with a different boolean equation for ice cream. His equation is ( ('''not''' choc) '''and''' ''fruit'') and ( ''HG'' or ( not ''HG'' ) ). Give an example of several ice cream flavors and makers of ice cream the young brother will like. |
;Question 4 (challenging) | ;Question 4 (challenging) | ||
: Can you find an ice cream flavor and maker that both our friend and his/her younger brother will like? | : Can you find an ice cream flavor and maker that both our friend and his/her younger brother will like? | ||
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| − | + | ===Shannon's MIT Master's Thesis: the missing link=== | |
| − | + | We are now coming to Shannon, who's influence on the field of computer science is quite remarkable, and whose contribution of possibly greatest influence was his Master's thesis at MIT, written in 1948. | |
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| + | Shannon knew of the need the military had for calculators (human beings or machines) that would compute tables of possible trajectories for shells fired from canons. He also knew of efforts by various groups in universities to build calculating machines using electricity and vacuum tubes (which had replaced relays). Because the machines used electricity and switches, the binary system with only two values, 0 and 1, was an interesting system to consider and exploit. But there was still an engineering gap in figuring out how to create circuits that would perform arithmetic operations on binary numbers in an efficient way. | ||
| + | In his thesis, Shannon presented the missing link, the bridge that would allow electrical/electronic computers to perform arithmetic computation. He demonstrated that arithmetic operations on binary numbers could be simply perform by electrical circuits that implemented the '''and''', '''or''' and '''not''' operators of Boole's algebra! | ||
Revision as of 21:54, 30 January 2012
--© D. Thiebaut 08:10, 30 January 2012 (EST)
