What are computer Input Technologies?
- Pointing Devices
- Pen-Based Computing
- Speech Recognition Systems
- Optical Scanning
Types of Input Technologies (Pointing Devices)
- Electronic Mouse – Moving mouse on pad moves cursor on screen. Pressing buttons on mouse activates activities represented by selected icons.
- Trackball – Stationary device with a roller ball on top used to move cursor on screen.
- Pointing Stick – Small button-like device which moves cursor in direction of pressure placed on stick.
- Touchpad – Small rectangular touch-sensitive surface which moves the cursor in the direction of finger moves on the pad.
- Touch Screen – Video display screen that emits a grid of infrared beams, sound waves, or a slight electric current that is broken when the screen is touched.
Other Input Technologies
- Pen-based Computing: Pressure-sensitive layer under slate-like liquid crystal display screen and software that digitizes handwriting, hand printing, and hand drawing Optical Scanning: Devices that read text or graphics and convert them into digital input for your computer
- Optical Character Recognition (OCR): The machine identification of printed characters through the use of light-sensitive devices
- Speech Recognition Systems:
- Discrete – user must pause between each spoken word
- Continuous – software can recognize conversationally - paced speech
- Magnetic Stripe – devices that read data stored in the magnetic stripe on the back of cards
- Smart Cards – devices that read a microprocessor chip embedded in a card
- Digital cameras – devices that allow you to capture, store, and download still photos and full motion pictures
- Magnetic Ink Recognition (MICR) – devices that can read characters printed on source documents with an iron oxide-based ink
- Video Output:
- Cathode Ray Tube (CRT) – similar to vacuum tubes in television
- Liquid Crystal Display (LCD) – electronic visual displays that form characters by applying an electrical charge to selected silicon crystals
- Printed Output:
- Inkjet Printers – spray ink onto the page
- Laser Printers – use an electrostatic process similar to a photocopying machine
What computer system technologies and functions are included in self-service kiosks?
- video touch screens as the primary user interface
- Magnetic stripe card reader
- Wireless links with PDAs, PCs, cellphones
- Speech recognition/ pen-based handwriting
- Image recognition, identification recognition
- Processing - networked special-purpose microcomputer terminals, etc.
- Output - built-in, high-speed thermal printer
What is the customer value of self-service kiosks for airline check-ins? What other services should be provided?
Reduced waiting time. Reduced cost for Airlines and better CRM.
What is the business value of self-service kiosk in the airline industry? Do self-service kiosks give airlines a competitive advantage? Why or why not?
- Business Value
- Reduce business costs
- Improve Customer relationships (CRM)
- Parity with competitors kiosk following Sept. 11
- Competitive necessity since most airlines have this
Computer Storage - Trade-Offs
- Cost/speed/capacity trade-offs as one moves from semiconductor memories to magnetic media, to optical disks.
- High-speed storage media cost more per byte and provide lower capacities.
- Large capacity storage media cost less per byte but slower
- Semiconductor memories used mainly for primary storage
- Magnetic disk/tape & optical disk devices used as secondary storage devices to greatly enlarge storage capacity.
- Primary storage circuits use RAM (random access memory) chips, which lose their contents when electrical power is interrupted (i.e. RAM is volatile)
- Secondary storage devices provide a more permanent (i.e. non-volatile) type of storage media for storage of data and programs
- Difference between Direct vs. Sequential Access
- Direct (or Random) Access – Each storage position has a unique address. Each storage position can be individually accessed without having to search through other storage positions.
- Sequential Access – Data are recorded one after another in a predetermined sequence. Locating an individual item of data requires searching the recorded data until the desired item is located.
- Used for Primary Storage:
- Small, Fast, Shock Resistant, Temperature Resistant
- Volatile – contents of memory is lost when power is interrupted
RAM vs. ROM:
- Random Access Memory (RAM) – each memory position can be both sensed and changed
- Read Only Memory (ROM) – can be read but not erased or overwritten eg. Used for Firmware
- Types of Magnetic Media
- Used for Secondary Storage: Fast, Large, Reasonably Priced,
- Floppy Disks – single disk inside a protective jacket
- Hard Disk Drives – several disks, access arms and read/write heads in a sealed module
- Redundant Arrays of Independent Disks (RAID) - disk arrays of interconnected microcomputer hard disk drives
- Magnetic Tapes - Read/write heads of magnetic tape drives record data in the form of magnetized spots on the iron oxide coating of the plastic tape.
What are the Business Applications of Optical Disks?
- Long-term archival storage of historical files of document images
- Publishing medium for fast access to reference materials in a convenient compact form
What is Radio Frequency Identification (RFID)?
- Newest and most rapidly growing storage cum identification technologies
- Small hardware called RFID chips (Passive and Active RFID chips)
- When reader within range, RFID chip responds with stored information
- Privacy concerns due to “invisible” nature of the transmission of data
How is Software Developed?
- Custom Software – software applications that are developed within an organization for use by that organization
- Commercial Off-the-shelf (COTS) Software – software that is developed by a software developer with the intention of selling the software in multiple copies
What are Application Software Alternatives?
- Purchase Commercial Off-The-Shelf Software
- Application Service Providers – companies that own, operate, and maintain application software and the computer system resources required to offer the use of the application software for a fee as a service over the Internet
- Purchasing the right to use specific software under the terms of the software licensing agreement
- Protects the vendor’s intellectual property right
What is System Software?
System Management Programs – programs that manage the hardware, software, network, and data resources of computer systems during the execution of various information processing jobs of end users
What are System Development Programs
They are programs that help users develop information system programs and procedures and prepare user programs for computer processing.
What is an Operating System?
- An integrated system of programs that:
- Manages the operations of the CPU
- Controls the input/output
- Storage resources/activities
- Provides various support services
- Primary purpose is to:
- Maximise productivity of a computer system
- Minimise amount of human intervention required during processing
- Assist application programs to perform common operations such as accessing a network, entering data, saving and retrieving files and printing or displaying output
Popular Operating Systems
- MS-DOS / Microsoft Windows
- Mac OS X
- Performance Monitors –monitor & adjust performance and usage of one or more computer systems to keep them running efficiently
- Security Monitors –monitor & control use of computer systems and provide warning messages and record evidence of unauthorized use of computer resources
- Application Servers - provides an interface between an operating system and application programs of users
- Middleware – helps diverse software applications and networked computer systems exchange data and work together more efficiently
What are the business benefits of adopting open-source software?
- Cost: Open source software licenses are free.
- Functionality: Developers around the world work continually to improve the software's features.
- Time: Open source software users can quickly identify bugs and developers can quickly fix this bugs – often before these problems become widely known.
- However, there exists a significant difference between licensing costs (free) and total cost of ownership (TCO). TCO includes installation, user training, and maintenance. In fact, licensing costs represent a very small percentage of overall costs.
- Organizations adopting open-source applications need to monitor, evaluate, and implement fixes and enhancements to open source software. Implementing these changes may become tricky if the organization has modified the software to meet internal needs.
What are the risks associates with open-source software? How can these risks be addressed?
- An open-source application may lose popularity and, therefore, community support. In short, all the "free" maintenance and upgrades might trickle to a halt.
- "Free" software comes with a few catches. Eg, organizations that use and adapt open source software to meet new business needs are commonly prohibited from repackaging and selling this code. What starts as open source must remain open source, and pulling apart open-source code from custom code is no simple matter. The thought of "free" software may cloud purchasing manager's judgment. He should consider the TCO when evaluating a package. However, a business manager may fail to appreciate the long-term cost savings a commercial package might have over a free package.
- Security remains one of the most commonly cited risks associated with open-source software but this is not a major problem. While it is true that a programmer could insert malicious code into an otherwise useful application, where would they release it? If the programmer releases this application through an active developer forum, other programmers would quickly spot and fix the problem. If an organization acquires its open-source software through some back-water channel, well, that's just plain careless.
What are the four levels of programming languages
- Machine Language:
- All program instructions written in binary codes unique to each computer.
- Programmers knowledgeable of internal operations of the specific type of CPU.
- Assembler Language:
- Alphabetic abbreviations/symbols used to represent operation codes & storage locations.
- High Level Language:
- Instructions use brief statements or arithmetic expressions.
- Each statement generates several machine instructions when translated by compilers or interpreters.
- Fourth Generation Language:
- Nonprocedural – programmers specify results while computer determines sequence of instructions to accomplish those results.
- Natural Language – very close to human language.
- Ties together data element and the procedures or actions that will be performed upon them
- Examples are Visual Basic, Turbo C++, C++, Object C++, and Java.
- Advantages include:
- OOP languages are easier to use and more efficient for programming GUI required by many applications
- Programmed objects are reusable
Web Languages & Services
- HTML – a page description language that creates hypertext or hypermedia documents
- XML – describes the contents of Web pages by applying identifying tags or contextual labels to the data in Web documents
- Java – an object-oriented programming language that is simple, secure and platform independent
- Assembler – translates symbolic instruction codes of programs written in an assembler language into machine language instructions
- Compiler – translates high-level language statements
- Interpreter – compiler that translates & executes each statement in a program one at a time
- Graphical Programming Interfaces
- Programming Editors
- CASE tools
- Definition of Data Resource Management
- A managerial activity that applies information systems technologies to the task of managing an organization’s data resources to meet the information needs of their business stakeholders
Definition of Traditional File Processing
Data are organized, stored, and processed in independent files of data records
Problems of File Processing
- Data Redundancy – duplicate data requires an update to be made to all files storing that data
- Lack of Data Integration – data stored in separate files require special programs for output making ad hoc reporting difficult
- Data Dependence – programs must include information about how the data is stored so a change in storage format requires a change in programs
- Other Problems
Definition of Database Management Approach
- Consolidates data records into one database that can be accessed by many different application programs.
- Software interface between users and databases
- Data definition is stored once, separately from application programs
Definition of Database Management Software (DBMS)
Software that controls the creation, maintenance, and use of databases.
- Database Development
- Most personal/SME databases use COTS packages like Microsoft Access, etc…
- Large enterprise-wide database and its development are controlled by Database Administrators (DBA) Data definition language (DDL) are used by DBA to determine:
- What data definition to be included
- What structure/relationships among the data elements
- Above info. Is catalogued/stored in DDL called Data dictionary – a catalog or directory containing metadata
- Metadata – data about data
- Some data dictionaries enforce standard data element definitions for end users and application programs
Definition of Database Interrogation
- Capability of a DBMS to report information from the database in response to end users’ requests
- Query Language – allows easy, immediate access to ad hoc data requests
- Report Generator - allows quick, easy specification of a report format for information users have requested
Definition of Database Maintenance
- Updating a database continually to reflect new business transactions and other events
- Updating a database to correct data and ensure accuracy of the data
Types of Databases
- Operational – store detailed data needed to support the business processes and operations of a company
- Distributed – databases that are replicated and distributed in whole or in part to network servers at a variety of sites
- External – contain a wealth of information available from commercial online services and from many sources on the World Wide Web
- Hypermedia – consist of hyperlinked pages of multimedia
Definition Data Warehouse System
Large database that stores data that have been extracted from the various operational, external, and other databases of an organization
Definition of Data Mart
Databases that hold subsets of data from a data warehouse that focus on specific aspects of a company, such as a department or a business process
Definition of Data Mining
- Analyzing the data in a data warehouse to reveal hidden patterns and trends in historical business activity Perform “market-basket analysis” to identify new product bundles.
- Find root causes to quality or manufacturing problems.
- Prevent customer attrition and acquire new customers.
- Cross-sell to existing customers.
- Profile customers with more accuracy.
- Definition of Internet
- A network made up of millions of smaller private networks each with ability to operate independent of, or in harmony with, all the other millions of networks, all connected together
Business Value of the Internet
- Possible cost savings because applications that use Internet, intranets and/or extranets are less expensive to develop, operate, and maintain than traditional systems.
- Attract new customers with innovative marketing and product offerings.
- Retaining present customers with improved customer service and support.
- Generating revenue through eCommerce applications.
A network inside an organization that uses Internet technologies to provide an Internet-like environment within the enterprise for information sharing, communications, collaboration, and the support of business processes
Network links that use Internet technologies to interconnect the intranet of a business with the intranets of its customers, suppliers, or other business partners
Telecommunications Network Components
- Terminals – any input/output device that uses telecommunications networks to transmit or receive data
- Telecommunications Processors– devices that perform control and support functions
- Telecommunications Channels & Media – media over which data are transmitted and received
- Computers – all sizes and types (refer section 2A)
- Telecommunications Control Software – programs that control telecommunications activities
Telecoms Components & Alternatives
- Types of Telecommunications Networks
- Wide Area Network (WAN) – network that covers a large geographic area
- Local Area Network (LAN) – network connecting information processing devices within a limited physical area
- Virtual Private Network (VPN) – secure network that uses the Internet as its main backbone network, but relies on network firewalls, encryption, and other security features of its Internet and intranet connections and those of participating organizations
- Client/Server – PCs and workstations, called clients are interconnected by local area networks and share application processing with network servers
- Network Computing – Thin clients provide a browser-based user interface for processing small application programs
- Peer-to-Peer – file-sharing software connects each PC to a central server or to another online user’s PC
- Cellular and PCS Systems – a geographic area divided into cells with one low-power transmitter device per cell used to relay calls from one cell to another
- Wireless LANs –high- or low-frequency radio technology installed in an office or building (infrared included)
- Wireless Web – wireless, Web-enabled information appliances accessing the Internet, intranets and extranets. Encourage use of :
- PDA, smart phones which are very thin clients Wireless Application Protocol (WAP) for web services 3G wireless technologies for better speed & apps
- Modems – convert digital signals from a computer into analog frequencies that can be transmitted over ordinary telephone lines
- Multiplexers – allows a single communications channel to carry simultaneous data transmissions from many terminals
- Switch – makes connections between telecommunications circuits in a network
- Router – intelligent communications processor that interconnects networks based on different protocols
- Hub – a port switching communications processor
- Gateway – connects networks using different communications architectures
Network Architectures & Protocols
- Protocol – standard set of rules and procedures for the control of communications in a network
- Network Architecture – the use of standard protocols, standard communications hardware and software interfaces and the design of a standard multilevel interface between end users and computer systems with the goal of promoting an open, simple, flexible, and efficient telecommunications environment
Telecoms Control Software
- Traffic Management – manage network resources and traffic to avoid congestion and optimize telecomss service levels to users Security – provide authentication, encryption, firewall, auditing and enforcement
- Network Monitoring – troubleshoot and watch over the network, informing network administrators of potential problems before they occur
- Capacity Planning – survey network resources and traffic patterns and users’ needs to determine how best to accommodate the needs of the network as it grows and changes