Copyright © 2010 by the Mc. Graw-Hill Companies, Inc. All rights reserved. Chapter 3 Computer Hardware Mc. Graw-Hill/Irwin
Learning Objectives l Understand the history and evolution of computer hardware l Identify the major types and uses of microcomputer, midrange, and mainframe computer systems l Outline the major technologies and uses of computer peripherals for input, output, and storage 3 -2
Learning Objectives l Identify and give examples of the components and functions of a computer system l Identify the computer systems and peripherals you would acquire or recommend for a business of your choice, and explain the reasons for your selection 3 -3
Case 1: IBM, Wachovia, and Paypal l Researchers at the Cancer Institute use grid computing technology to convert images of cancerous tissues and cells into digital images – The grid checks digitized images for accuracy to ensure the bits/bytes translate into diagnoses – IBM, researchers, and doctors are building an image database to help oncologists diagnose and treat cancer patients faster and better l Grid computing technologies avoid the need for expensive, dedicated hardware – The processing load is distributed among commoditypriced equipment 3 -4
Case Study Questions l Applications for grid computing in this case include medical diagnosis and financial transaction processing – What other areas would be well suited to the use of grid computing, and why? l Provide examples from organizations other than those included in the case 3 -5
Case Study Questions l The joint effort by IBM and the Cancer Center of New Jersey works by digitalizing medical diagnoses on the World Community Grid – What are the advantages & disadvantages of relying on a volunteer-based network? 3 -6
Case Study Questions l IBM, Wachovia, and Paypal are arguably large organizations. However, several vendors have started offering computing power for rent to smaller companies, using the principles underlying grid computing – How could small and medium companies benefit from these technologies? 3 -7
Pre-Computer Calculations l Counting on fingers and toes l Stone or bead abacus l 1642: first mechanical adding machine l Age of industrialization – Calculate comes from calculus, the Latin word for small stone – Invented by Blaise Pascal, wheels moved counters – Modified in 1674 by Von Leibnitz – Mechanical loom used punch cards 3 -8
Early Computing l 19 th Century – Charles Babbage proposed the Analytical Engine, which could calculate, store values in memory, perform logical comparisons – Never built due to of lack of electronics l 1880 s – Hollerith’s punched cards used to record census data using On/Off patterns – The holes turned sensors On or Off when run through tabulating machine – This company became the foundation for IBM 3 -9
Electronic Computers l 1946 - First Generation Computer – ENIAC – Programmable – 5000 calculations per second – Used vacuum tubes – Drawbacks were size and processing ability l 1950 s – ENIAC replaced by UNIVAC 1, then IBM 704 – Calculations jumped to 100, 000 per second 3 -10
Waves of Computing l Late 1950 s - Second Generation – Transistors replaced vacuum tubes – 200, 000 to 250, 000 calculations per second l Mid-1960 s - Third Generation – Integrated circuitry and miniaturization l 1971 - Fourth Generation – Further miniaturization, multiprogramming, virtual storage l 1980 s - Fifth Generation – Millions of calculations per second 3 -11
Microcomputers l 1975 – ALTAIR, programmed by flicking switches l 1977 – Commodore & Radio Shack produce PCs l 1979 – Apple computer, the fastest selling PC thus far l 1982 – IBM introduced the PC, which changed the market 3 -12
Categories of Computer Systems 3 -13
Microcomputer Systems Called a personal computer or PC Computing power now exceeds that of the mainframes of previous generations Relatively inexpensive Networked professional workstations used by businesses Hand-held, notebook, laptop, tablet, portable, desktop, and floor-standing 3 -14
Recommended PC Features 3 -15
Microcomputer Uses Workstations Network Servers Supports heavy mathematical computer and graphics display demands More powerful than workstations CAD, investment, and portfolio analysis Coordinates telecommunications and resource sharing Supports small networks and Internet or intranet websites 3 -16
Microcomputer Uses l Terminals – Any device that allows access to a computer l Types – Dumb – Intelligent (Windows or Internet) – Transaction 3 -17
Corporate PC Criteria Solid performance at a reasonable price l Operating system ready l Connectivity l Security-equipped l 3 -18
Information Appliances l Hand-held microcomputer devices l Known as personal digital assistants (PDAs) – Web-enabled PDAs use touch screens, handwriting recognition, or keypads – Mobile workers use to access email or the Web, exchange data with desktop PCs or servers – Latest entrant is the Black. Berry l PDAs include – Video-game consoles – Cellular and PCS phones – Telephone-based home email appliances 3 -19
Midrange Systems l High-end network servers that handle large-scale processing of business applications – Not as powerful as mainframes – Less expensive to buy, operate, maintain l Often used to manage – Large Internet websites, intranets, extranets – Integrated, enterprise-wide applications – First became popular as minicomputers l Used as front-end servers – Assists mainframes with telecommunications and networks 3 -20
Mainframe Computer Systems l Large, fast, powerful computer systems – Large primary storage capacity – High transaction processing – Handles complex computations l Widely used as superservers for… – Large client/server networks – High-volume Internet websites l Becoming a popular computing platform for… – Data mining, warehousing, electronic commerce applications 3 -21
Supercomputer Systems l Extremely powerful systems designed for… – Scientific, engineering, and business applications – Massive numeric computations l Markets include… – Government research agencies – Large universities – Major corporations l Uses parallel processing – Billions to trillions of operations per second (gigaflops and teraflops) 3 -22
The Next Wave of Computing Harnessing the infinite amount of unused computing power Desktops and laptops within an organization Distributed or grid computing Parallel computing that relies on complete computers connected to a network Harnesses the unused CPU power in all connected computers, even between organizations 3 -23
Computer System Concept Input System of hardware devices organized by function Processing Control Storage Output 3 -24
Computer System Concept 3 -25
Computer Processing Speeds l Early computers – Milliseconds (thousandths of a second) – Microseconds (millionths of a second) l Current computers – Nanoseconds (billionth of a second) – Picoseconds (trillionth of a second) l Program instruction processing speeds – Megahertz (millions of cycles per second) – Gigahertz (billions of cycles per second) l Commonly called “clock speed” 3 -26
Computer Processing Speeds l Throughput – Ability to perform useful computation or data processing assignments during a given period l Speed is dependant on… – Size of circuitry paths (buses) that interconnect microprocessor components – Capacity of instruction processing registers – Use of high-speed cache memory – Use of specialized microprocessors, such as math coprocessor 3 -27
Moore’s Law Doubling of the number of transistors per integrated circuit every 18 to 24 months 3 -28
Case 2: Apple, Microsoft, IBM, and Others l WIMP – Windows, icons, menus, and pointing devices have dominated computing for 15 years – New human interface technologies will revolutionize the way we interact with computers l Microsoft is working with Starwood Hotels & Resorts to introduce surface computing – Hotel guests use a virtual concierge to manipulate maps, photos, restaurant menus… l A logical extension of touch technology is gesture recognition – Hand or finger movements across a screen, or close to it, without requiring an actual touch 3 -29
Case Study Questions l What benefits may Starwood Hotels derive from the introduction of touch-screen technology, as noted in the case? – What possible disruptions may occur as a result? 3 -30
Case Study Questions l Bill Buxton of Microsoft stated that “Touch now may be where the mouse was in about 1983” – What do you make of his comments, and what do you think it would take for touch technology to displace the WIMP interface? l Advanced touch-screen technology is really a solution in search of a problem – Do you agree with this statement? 3 -31
Peripherals Peripheral Generic name for all input, output, and secondary storage devices Parts of the computer system (not the CPU) All online devices Online Devices Separate from the CPU, but electronically connected to (and controlled by) it Offline Devices Separate from, and not under the control of, the CPU 3 -32
Peripherals Advice 3 -33
Input Technologies l Common input devices – Keyboard – Graphical User Interface (GUI) – Electronic mouse and trackball – Pointing stick – Touchpad – Touchscreen 3 -34
Pen-Based Computing l Used in Tablet PCs and PDAs – Pressure-sensitive layer, similar to touch screen, under liquid crystal display screen – Software digitizes handwriting, hand printing, and hand drawing 3 -35
Speech Recognition Systems l Speech may be the future of data entry – Easiest, most natural means of human communication l Recognizing speech patterns – Discrete, requires pauses between each word – Continuous speech recognition software (CSR) recognizes continuous, conversationally paced speech 3 -36
Speech Recognition Software l Speech recognition systems digitize, analyze, and classify speech and sound patterns – Compares to a database of sound patterns – Passes recognized words to software – Typically requires voice recognition training l Speaker-independent systems – Allow computers to recognize words from a voice never heard before – Typically used in voice-messaging computers 3 -37
Optical Scanning l Devices read text or graphics and convert them into digital computer input – Enables direct entry of data from source documents l Document management library system – Scans documents, then organizes and stores them for easy reference or retrieval 3 -38
Optical Scanning Scanners Compact desktop models are popular for low cost and ease of use Larger, more expensive flatbed scanners are faster, offer high-resolution color scanning Optical Character Recognition (OCR) Software that reads characters and codes Used to read merchandise tags, sort mail, score tests, read bar codes 3 -39
Other Input Technologies Magnetic Stripe Smart Cards Digital Cameras Magnetic Ink Character Recognition (MICR) 3 -40
Output Technologies Voice Response Increasingly found along with video displays in business applications Video Displays Cathode-ray tube (CRT) Liquid crystal display (LCD) Plasma displays (TVs, flat-panel monitors) Printed Output Inkjet and laser 3 -41
Storage Tradeoffs 3 -42
Computer Storage Fundamentals Uses two-state (binary) data representation Bit Byte On (1) or Off (2) Data processed & stored in computer systems through On/Off signals Smallest element of data Either zero or one Group of eight bits, which operate as a single unit Represents one character or number 3 -43
Representing Characters in Bytes 3 -44
Using Binary Code to Calculate 3 -45
Storage Capacity Measurement Kilobyte (KB) One thousand bytes Megabyte (MB) One million bytes Gigabyte (GB) One billion bytes Terabyte (TB) One trillion bytes Petabyte (PB) One quadrillion bytes 3 -46
Direct (Random) and Sequential Access 3 -47
Semiconductor Memory l Microelectronic semiconductor memory chips are used for primary storage – Advantages: small size, fast, shock and temperature resistance – Disadvantages: volatility; must have uninterrupted electric power or loses memory 3 -48
Types of Semiconductor Memory Random Access Memory (RAM) Read-Only Memory (ROM) 1. Most widely used primary storage medium 1. Permanent storage 2. Volatile memory 3. Frequently used programs burnt into chips during manufacturing 3. Read/write memory 2. Can be read, but not overwritten 4. Called firmware 3 -49
Flash Drives l Sometimes called a jump drive – Uses a small chip containing thousands of transistors – Can store data for virtually unlimited periods without power – Easily transported – Highly durable – Storage capacity of up to 20 GB – Plugs into any USB port 3 -50
Magnetic Disks Hard Disk Drives & Floppy Disks (diskettes) l Used for secondary storage – Fast access and high capacity – Reasonable cost 3 -51
RAID Storage l Redundant Arrays of Independent Disks – Provides virtually unlimited online storage – 6 to more than 100 hard disk drives are combined into a single unit – Data is accessed in parallel, over multiple paths, from many disks – Redundant storage of data on several disks provides fault-tolerant capacity l Storage area networks can interconnect many RAID units 3 -52
Magnetic Tape l Secondary storage – Tape reels, cassettes, and cartridges – Used in robotic, automated drive assemblies – Archival and backup storage – Lower-cost storage solution 3 -53
Optical Disks 3 -54
Uses of Optical Disks Image Processing Long-term storage of historical image files Storage of scanned documents Publishing Medium Allows fast access to reference materials Catalogs, directories, and so on Interactive Multimedia Applications Video games, educational videos, and so on 3 -55
Radio Frequency Identification (RFID) l One of the newest, fastest growing storage technologies – System for tagging and identifying mobile objects – Used with store merchandise, postal packages, casino chips, pets – Special reader allows objects to be tracked as they move from place to place – Chips half the size of a grain of sand l Passive chips derive power from reader signal – Active chips are self-powered 3 -56
RFID Versus Bar Coding Scans from greater distance RFID Can store data More information can be tracked Privacy Concerns Invisible nature of the system Capacity to transmit fairly sophisticated messages 3 -57
Case 3: Kimberly-Clark & Daisy Brand Kimberly-Clark Almost $20 billion in sales in 37 countries Wants to evolve into a demand-driven supply network Uses SAP forecast-to-stock and order-to-cash processes Has been redesigning business processes and finding a way for technology to support those processes RFID helps trace trailers and raw materials 3 -58
Case 3: Kimberly-Clark & Daisy Brands Sells perishable products through Wal-Mart RFID helps manage flow of product and ensures marketing promotions proceed as planned Lets customers track their orders Knows when pallets of product arrive, and when they’re unpacked Can dispatch people to investigate anomalies 3 -59
Case Study Questions l Kimberly-Clark and Daisy Brands were two of the earliest adopters of RFID through their relationship with Wal-Mart – How has that initiative fared since it was announced? l Go online and research the most recent developments – Prepare a report to highlight any successes and failures in the advancement toward a fully RFID-enabled supply chain for the giant retailer 3 -60
Case Study Questions l What is the value of having access to realtime (or near real time) information about sales and inventory? – Are there any dangers to having this capability, such as overreacting to short-term trends? 3 -61
Скачать презентацию Copyright 2010 by the Mc Graw-Hill Companies
5f96926ce57b92531454345a15b7c0aa.ppt