Learning Module D: Information Technology Systems

I. IT Systems What are Five Components of Information Systems? - Hardware: equipment, devices - Software: programs - a set of instructions that

controls hardware - Data: files, database - People: technical personnel, users - Procedures: documents that help people use and

manage MIS (manuals, data dictionary, system operation manuals, …

1. Data

• Data: facts about objects

• Store data in computer:

– binary data

– bits

– bytes

• Five types of data

What are Five Types of Data and What is Multimedia?

• Number (.txt, .xls)• Text (.txt, .xls)• Image (.bmp)• Sound (.wav)• Video (.avi)

• Multimedia

How are the Five Types of Data Represented in IT Systems?

• Number: Base 2 numbers (binary)• Text: character set

– ASCII (American Standard Code for Information Interchange), e.g., A 65, B 66.

– EBCDIC (Extended Binary Coded Decimal Interchange Code), for IBM Mainframe.

– Different countries may use different character set.

• Picture: 2 formats– Pixel format (.bmp, .jpg, paintbrush)

• binary number -> dot for color• resolution - dpi (dots per inch) & storage

space – Vector format (autocad)

• Engineering drawings• Mathematical description -> less storage

space

• Sound:– two components of sound: volume and pitch– digitize sound

• Sampling: take observations of two values (volume and pitch) several times per second (.wav)

• Video:– Tremendous amount of data (100 CD’s for

one-hour movie)– Data compression

2. Hardware Components of Computer System

What are Components of Computer Systems?

• Input

• Output

• Processor

• Secondary Storage

• Input – Keyboard– Pointing devices: mouse, light pen, touch

screen– Scanner– Pen-based systems: pen & software for

converting handwriting to text– Sound: microphone and sampler– Voice recognition (expensive)– Video capture board: digitize video

• Output – Monitor

• resolution: # of pixels & colors• video card & video RAM

– Printer• laser• ink-jet• dot-matrix

• Process System – Processor: CPU (Central Processing Unit):

carries out instructions; Control Unit + Arithmetic Logic Unit

– RAM (Random Access Memory)– Speed vs. Internal Clock

• Speed: MIPS• Internal clock: 100MHz, 450MHz• Speed clock speed (# of clock cycles per

instruction, 486D50 is slower than Pentium 50)• Comparable only for the same manufacturer

and the same family

– Speed depends on other components• Data bus• Access time and capacity of RAM• Parallel processors

– Price differential• PC - the lowest $/MIPS• Use for different purposes (e.g., IBM

Mainframe for multiple users)

• Secondary Storage – hard drive– floppy disk drive– tapes (backup)– optical drive

• CD-ROM (650 megabytes)• WORM (Write Once Read Many)• Erasable• DVD (Digital Video Disk)

– Solid State/RAM (keep data when power is off)

3. Software

Programs• Systems software

– Operating systems– Utilities– Language translators

• Applications (Personal Productivity Software)

What are Operating Systems?

• A program that acts as an intermediary between users and hardware

• Three functions of OS– allocation and assignment of resources– scheduling of jobs– monitoring activities (security, usage)

• Specific operating systems– VMS (DEC VAX)– MVS (IBM Mainframe)– UNIX (machine-independent)– OS/2 (IBM PC, robust and memory-

intensive)– Windows 98 (PC) – Windows NT (workstation, network server)– Windows 2000 (Peer-to-Peer)

• GUI (Graphical User Interface)

• Multitasking– Users can run more than one job at the same

time– OS rotates jobs, not exactly run them at the

same time– Reduce total processing time (OS

coordinates all components of computer system)

– Prevent users from changing data at the same time (concurrency problem).

What Are Examples of Application Software?

• DBMS: Access• Calculation: Excel• Writing: Word• Presentation: PowerPoint• Communication: Email (Outlook Express)• Scheduling: Microsoft Outlook

II. Information in an Organization

Three Levels of Management Decision• Operation Level:

– day-to-day operations– follow rules (structured decision)– transaction for collecting data

• Tactical Level:– managers’ specialization– structured and unstructured decisions– short-term to middle-term– without major changes to organization’s structure

(continued)

• Strategic Level:– top management– unstructured decision– long-term– with major changes to organization’s structure

1. What are the five categories of information-processing task? (p.12)– Capture information– Present information in useful form– Create new information– Store information– Sending information to other people

2. Why Point of origin or point of sales (POS)?• Capture data at the point of origin (the sales register

is a computer terminal connected to a central computer).

• Keyboard (gas station)• Bar code scanner (supermarket)• Optical character recognition (OCR) read

handwritten zip code• Magnetic ink character recognition (MICR) - more

accurate than OCR• Error detection, computations and immediate update• Avoid - rekey data, lost data, duplicate data,

inaccuracies, long time, fail to identify error.

3. How is TPS Used for Manufacturing?

Process Control

• Manufacturing machines are connected to computers or have built-in computers.

• Monitor production levels.

• Monitor quality.

• Monitor uptime or downtime.

• Problems

– standard for various machines

– an enormous amount of data: how to use, how to store, how to transmit.

4. What is Electronic data interchange (EDI)?• The direct computer-to-computer exchange

between two firms of standard business transaction documents (invoices, bills, purchase orders) or send documents through a third-party EDI provider.

• Cut lead time and improve quality control• Lock in customers (easier for customers or

distributors to order)• Standard: software and hardware, data

definitions, format of documents

5. Web Database Applications

Why do business on the Internet?– Expanded reach– Corporate image enhancement– Improved customer service– Follow-up sales/marketing material– New product/service delivery channel– Reduced operating expenses possibly– Test marketing (new products, new services,

new market campaigns)