Lecture Notes

History of the Development of Computers

Personal Computer History

Early Computer System Development

http://personalpages.manchester.ac.uk/staff/m.dodge/cybergeography//atlas/historical.html

Introduction to Computer Architecture

Hardware

Internet & WWW 2011

Internet 2012

Major Domain Census http://blog.icann.org/2009/03/tld-census/

Size, Structure & Growth Rate of the Internet

· http://www.technologyreview.com/Infotech/18944/?a=f

· http://upload.wikimedia.org/wikipedia/commons/d/d2/Internet_map_1024.jpg

· http://www.physorg.com/news151162452.html

· http://www.lk.cs.ucla.edu/internet_history.html

· http://en.wikipedia.org/wiki/History_of_the_Internet

· http://en.wikipedia.org/wiki/History_of_the_World_Wide_Web

Flash Drives

· http://en.wikipedia.org/wiki/USB_flash_drive

· http://en.wikipedia.org/wiki/Solid-state_%28electronics%29

· silicon dioxide cells – frontend ≈ EEPROM technology

· read unit – byte size

· write unit, i.e., erase unit – large blocks

· embedded processor rewrites blocks

· silicon dioxide cells suffer from deterioration due to repeated usage (write/erase)

Gates & Flip-Flops

· Part 1

Mass Storage Systems

· File -- group of logical records

· Logical Record -- group of data items concerning a specific entity

· Field – specific data categories in a logical record

· Key Field

· Physical Record -- block of data, usually multiple files, records or portions of records,

conforming to the specific characteristics of a particular storage device

· Buffers

Data Representation

· dictionary encoding

· bitmap – collection of pixels

·

Human Hearing

Frequency == Sound Pressure

can be measured in mmHg

image representation – geometric structures – zoom ability

o JPEG

§ http://en.wikipedia.org/wiki/Luminance

§ http://en.wikipedia.org/wiki/Chrominance

· sound

o sampling rate

musical CD’s

44,100 samples/second x-axis

each sample 32 bits y-axis 32 divisions

one second of music requires > 1,000,000 bits

§ Sound is a traveling longitudinal wave which is an oscillation of pressure. Humans perceive frequency of sound waves as pitch. Each musical note corresponds to a particular frequency which can be measured in hertz. An infant's ear is able to perceive frequencies ranging from 20 Hz to 20,000 Hz; the average adult human can hear sounds between 20 Hz and 16,000 Hz.^[7] The range of ultrasound, high-intensity infrasound and other physical vibrations such as molecular vibrations extends into the megahertz range and well beyond. -- Wikipedia

Musical instrument Digital Interface (MIDI)

<instrument, musical note, start time, end time>

one second of music requires 3 bits