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Explains how digital systems such as the computer represent numbers. Covers the basics of boolean algebra and binary math.

Computer architecture

To understand digital signal processing systems, we must understand a little about how computers compute. The moderndefinition of a computer is an electronic device that performs calculations on data, presenting theresults to humans or other computers in a variety of (hopefully useful) ways.

Organization of a simple computer

Generic computer hardware organization.

The generic computer contains input devices (keyboard, mouse, A/D (analog-to-digital) converter, etc.), a computational unit , and output devices (monitors, printers, D/A converters). Thecomputational unit is the computer's heart, and usually consists of a central processing unit (CPU), a memory , and an input/output (I/O) interface. What I/O devices might be present on a givencomputer vary greatly.

  • A simple computer operates fundamentally in discrete time. Computers are clocked devices, in which computational steps occur periodically according to ticksof a clock. This description belies clock speed: When you say "I have a 1 GHz computer," you mean that your computertakes 1 nanosecond to perform each step. That is incredibly fast! A "step" does not, unfortunately,necessarily mean a computation like an addition; computers break such computations down into several stages, whichmeans that the clock speed need not express the computational speed. Computational speed is expressed inunits of millions of instructions/second (Mips). Your 1 GHz computer (clock speed) may have a computational speedof 200 Mips.
  • Computers perform integer (discrete-valued) computations. Computer calculations can be numeric (obeying the laws of arithmetic), logical (obeyingthe laws of an algebra), or symbolic (obeying any law you like). An example of a symbolic computation is sorting a list of names. Each computer instruction that performs an elementary numeric calculation --- an addition, a multiplication, or adivision --- does so only for integers. The sum or product of two integers is also an integer, but the quotient oftwo integers is likely to not be an integer. How does a computer deal with numbers that have digits to the rightof the decimal point? This problem is addressed by using the so-called floating-point representation of real numbers. At its heart, however, this representation relies on integer-valued computations.

Representing numbers

Focusing on numbers, all numbers can represented by the positional notation system . Alternative number representation systems exist. For example, we could use stick figure counting orRoman numerals. These were useful in ancient times, but very limiting when it comes to arithmetic calculations: ever triedto divide two Roman numerals? The b -ary positional representation system uses the position of digits ranging from0 to b -1 to denote a number. The quantity b is known as the base of the number system. Mathematically, positional systems represent the positiveinteger n as

d k d k 0 b 1 n k 0 d k b k
and we succinctly express n in base- b as n b d N d N 1 d 0 . The number 25 in base 10 equals 2 10 1 5 10 0 , so that the digits representing this number are d 0 5 , d 1 2 , and all other d k equal zero. This same number in binary (base 2) equals 11001( 1 2 4 1 2 3 0 2 2 0 2 1 1 2 0 )and 19 in hexadecimal (base 16). Fractions between zero and one are represented the same way.
d k d k 0 b 1 f k -1 d k b k
All numbers can be represented by their sign, integer and fractional parts. Complex numbers can be thought of as two real numbers that obey special rules to manipulate them.

Questions & Answers

Discuss the differences between taste and flavor, including how other sensory inputs contribute to our  perception of flavor.
John Reply
taste refers to your understanding of the flavor . while flavor one The other hand is refers to sort of just a blend things.
Faith
While taste primarily relies on our taste buds, flavor involves a complex interplay between taste and aroma
Kamara
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omeprazole
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Omeprazole Cimetidine / Tagament For the complicated once ulcer - kit
Patrick
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Nency Reply
Not really sure
Eli
to drain extracellular fluid all over the body.
asegid
The lymphatic system plays several crucial roles in the human body, functioning as a key component of the immune system and contributing to the maintenance of fluid balance. Its main functions include: 1. Immune Response: The lymphatic system produces and transports lymphocytes, which are a type of
asegid
to transport fluids fats proteins and lymphocytes to the blood stream as lymph
Adama
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Oyindarmola Reply
Anatomy is the identification and description of the structures of living things
Kamara
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Oyerinde Reply
Anatomy is the study of the structure of the body, while physiology is the study of the function of the body. Anatomy looks at the body's organs and systems, while physiology looks at how those organs and systems work together to keep the body functioning.
AI-Robot
what is enzymes all about?
Mohammed Reply
Enzymes are proteins that help speed up chemical reactions in our bodies. Enzymes are essential for digestion, liver function and much more. Too much or too little of a certain enzyme can cause health problems
Kamara
yes
Prince
how does the stomach protect itself from the damaging effects of HCl
Wulku Reply
little girl okay how does the stomach protect itself from the damaging effect of HCL
Wulku
it is because of the enzyme that the stomach produce that help the stomach from the damaging effect of HCL
Kamara
function of digestive system
Ali Reply
function of digestive
Ali
the diagram of the lungs
Adaeze Reply
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Diya Reply
37 degrees selcius
Xolo
37°c
Stephanie
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Mark
36.5
Simon
37°c
Iyogho
the normal temperature is 37°c or 98.6 °Fahrenheit is important for maintaining the homeostasis in the body the body regular this temperature through the process called thermoregulation which involves brain skin muscle and other organ working together to maintain stable internal temperature
Stephanie
37A c
Wulku
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Diya Reply
anaemia is the decrease in RBC count hemoglobin count and PVC count
Eniola
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Diya Reply
how does Lysin attack pathogens
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acid
Mary
I information on anatomy position and digestive system and there enzyme
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anatomy of the female external genitalia
Muhammad Reply
Organ Systems Of The Human Body (Continued) Organ Systems Of The Human Body (Continued)
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what's lochia albra
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Source:  OpenStax, Fundamentals of electrical engineering i. OpenStax CNX. Aug 06, 2008 Download for free at http://legacy.cnx.org/content/col10040/1.9
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