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Learning Module D: Information Technology SystemsI. 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)