Chapter 1

parisfawnAI and Robotics

Nov 17, 2013 (3 years and 6 months ago)

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Chapter 3

Computer Hardware

2

II. A Brief History of Computer

Hardware

Without computers many technological
achievements would not have been
possible:


Counting with fingers/toes


Blaise Pascal, 1642


invented the first
mechanical adding machine


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A Brief History of Computer Hardware


Herman Hollerith


Hollerith’s Punch Card
system to record
census data in late
1880’s; 1911


merged
with competitor to
form IBM



ENIAC (Electronic
Numerical Integrator
and Calculator), 1946


the world’s first
electronic digital
computer


4

II. A Brief History of Computer

Hardware


1950’s


Transistors were invented
and replaced tubes



1958


Integrated Circuit (“chip”) was
invented



1970’s


1980’s


Further miniaturization of circuits


Apple Computer and IBM PC

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III. Types of Computer Systems


Computers come in a variety of sizes,
shapes, and computing capabilities




Mainframes



Midrange (obsolete due to powerful
microcomputers)



Microcomputers

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IV. Microcomputer Systems

(Personal Computer)

The most important category for
businesses and consumers, exceeds the
power of many mainframes


Workstations


support mathematical and
graphical demands



Network Servers


support
telecommunications and resource sharing



Computer Terminals


any device that
allows access to a computer


7

IV. Microcomputer Systems (Personal

Computer)


Network Computers


designed specifically
for use with networks and the Internet; low
TCO (total cost of ownership)



Information Appliances


Web
-
enabled
devices for accessing information from
anywhere


cell phones, PDAs, handheld
PCs


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Corporate PC Criteria


Why laptops instead of desktops?



Why would a change in OS be
disruptive?



What are the strengths vs. risks of
cabled vs. wireless PCs?


9

V. Midrange, Mainframe, and

Supercomputer Systems


Midrange Systems


popular as Network
Servers; disappearing due to
microcomputers



Mainframe Systems


large, fast, and
powerful, used for high transaction
processing and complex computations; used
by corporations and government agencies



Supercomputers


extremely powerful,
extremely high speeds and massive numeric
computations


10

V. Midrange, Mainframe, and

Supercomputer Systems


The Next Wave of Computing


minisupercomputers; connecting all the
power of unused desktops in an
organization


Distributed (Grid) Computing


parallel
computing over a network


Advantages


purchase nodes as a commodity,
economies of scale


Disadvantages


untrustworthy calculations, lack of
centralized control


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The Computer System

12

VII. Moore’s Law


Moore’s Law 1965


the
number of transistors on
a chip will double every
18
-
24 months


essentially, the power or
speed of a computer will
double every 18
-
24
months


The Price would halve in
that same time, which
has also proven to be
true


Recent statistics indicate
this time has decreased
to 12 months


13

Section 2

Computer Peripherals: Input, Output, and
Storage Technologies

Peripheral
-

a generic name for all input,
output, and secondary storage devices not
part of the CPU (basically, what is
connected to the
outside

of the computer)

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II. Input technologies


Input Devices


keyboards, mice, light
pens, trackballs, touch screens


Speech Recognition Systems


understands spoken commands/words


Discrete Speech Recognition


speak each word
separately


Continuous Speech Recognition


recognizes
conversationally
-
paced speech


Speaker
-
Independent Voice Recognition


understands speech from a voice it has never
heard before

15

II. Input technologies


Optical Scanning


converts text or
graphics to digital input for direct entry
of source documents


Other Input Technologies


Magnetic Stripe


on credit cards


Smart Cards


contain an embedded chip


Digital Cameras


Magnetic Ink Character Recognition (MICR)


used in banking industry

16

Forget the ATM: Deposit Checks Without
Leaving Home


What does federal Check 21 Act allow?



What is the concern of consumers
remotely depositing checks?



What basic security is provided?



What limits/restrictions are placed on
the consumers?


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IV. Storage Tradeoffs

18

IV. Storage Tradeoffs


Direct and Sequential Access


Direct Access and Random Access are the same
concept; locate an address on the storage
device and go directly to that location for data
access


Sequential Access


All tape devices are
accessed serially


device must be read one
record at a time from the data until the desired
data is found

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VI. Magnetic Disks


Hard drives are the
most common form of secondary storage



RAID (Redundant Arrays of Independent Disks)
Storage


interconnected groups of hard drives
-

fast speeds and fault tolerant (redundant
backups)

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V. Semiconductor Memory


RAM (Random Access Memory)


volatile, may
be read and over
-
written



ROM (Read Only Memory)


non
-
volatile, may
be read but not over
-
written or erased; PROM
and EPROM may be reprogrammed



Flash (Jump) Drives


solid
-
state memory

21

IV. Storage Tradeoffs


Computer Storage Fundamentals


Binary Representation


Two
-
state, on/off, +/
-
,
0/1


Bit


Binary digit, 0/1


Byte


Grouping of bits (typically 8 bits/byte),
represents a single character


ASCII


formalized code determining what byte
values represent which character


Storage capacities


kilobytes (KB), megabytes
(MB), gigabytes (GB), terabytes (TB)

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Representing characters in bytes

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VII & VIII. Magnetic Tape & Optical Disks



Magnetic Tape


slow speeds, but
inexpensive for large amounts of
backups



Optical Disks


CD
-
ROM, CD
-
R, DVD
-
R
(cannot be erased or re
-
written); CD
-
RW,
DVD
-
RW (may be erased or re
-
written)

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VII. Radio Frequency Identification (RFID)


RFID


for tagging and identifying mobile objects
(store merchandise, postal objects, sometimes
living organisms); provides information to a
reader when requested


Passive


no power source, derives power from the

reader signal



Active


self
-
powered, do not need to be close to the

reader



RFID Privacy Issues


may be used as spychips; gathers

sensitive information about an individual without

consent