Unit I


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Unit I

  1. 1. UNIT-I Computer Applications in Management Role of Computers • Computers are now affecting every sphere of human activity and are bringing about many changes in Industry, Government, Education, Medicine, Scientific / Business Research, Law, Social Sciences and even in arts like music and painting, etc. • The areas of applications of computers are confined only by limitations on human creativity and imagination. • It is essential, therefore, for every educated person to know about computers, their strengths, weaknesses, and their internal structure. Personal Benefits of Learning about Computers • Improved Employment Prospects: computer related skills have become essential in many careers. Knowledge of computers will make you marketable to prospective employers. • Skills that span different aspects of life: You will find your computer skills valuable regardless of the setting – at home, work, college, or play. • Greater Self Sufficiency: Computers are tools, and you can use them in several situations to become actually more self sufficient. • Foundation Knowledge for Life Time Learning: By mastering the fundamental concepts, you will develop a strong base that will support your learning for years to come. • Normally, we do not study computers in isolation. • In the age of convergence of technologies, it is more appropriate to consider a wider perspective of computers, viz., the Information Technology. • IT is a term that encompasses all forms of technology used to create, store, exchange, and use information in its various forms – Business data, Voice conversations, Still images, Motion Pictures, Multimedia presentations, and other forms, including those not yet conceived. • It is Information Technology that is driving what has often been called “The Information Revolution”. Influence of IT on Business Organizations • Modern business organizations today are facing extreme competitive pulls and need to develop systems to cope with such pressures: • Pressures – Globalization of Industry – Enlarged scope of Business
  2. 2. – Enlarged geographical spread. – Increasing competition – Increase in expectation of customers in terms of • Better quality, Lower costs, newer products, more variety, quicker deliveries. • Growing environmental demands: – Faster response to customer inquiries – Reduction in turnaround time – Faster design – Faster communication – Total Quality Management – Up-to-date information with all concerned. The Drivers of Change Business Pressures on an Organization that force change What is in IT for Me? As students of Management, it is important for you to know how computers or Information Technology is being applied in various management areas. ACCOUNTING • Data and Information are integral to the accounting function. • Information Systems capture, organize, analyze and disseminate data and information throughout modern organizations. • Virtually no companies in the modern business world handle their accounting without support from computers. • Accounting IS commonly integrates with other IS so that transactional information from a sales or marketing IS becomes input for the accounting IS. FINANCE
  3. 3. • The modern financial world turns on speed, volume, and accuracy of information flow, all facilitated by advanced information systems and telecommunications. • IS can monitor world financial markets, support financial decision making, e.g., for portfolio Management, provide quantitative analyses, e.g. for cash flow projections, and support a host of other financial functions. MARKETING • The Internet and the World Wide Web (WWW) have opened an entirely new channel for marketing from business to business and business to consumer. • They have also dramatically increased the amount of information available to customers, allowing rapid and thorough product and price comparisons. • The Internet also provides for much closer contact between the consumer and the supplier. • The e-commerce venue continues to grow in size and sophistication so that every one contemplating a career in marketing must be thoroughly trained in its unique technologies and techniques. • PRODUCTION / OPERATIONS MANAGEMENT • Every process in a product or service’s value chain can be enhanced by the use of computer-based IS. • In Manufacturing, these processes occur everywhere from supplier production and logistics, through the manufacturing process, through outbound logistics, and after the sale of the product. • The value chains in service industries are also a series of processes that benefit from IS support. • IS have transformed the competitive landscape by the use of IT from CAD and CIM, through Internet-based Order systems. Human Resources Management • HRM is changing radically with the use of IS. • Record Keeping has greatly improved in terms of speed, convenience and accuracy. • Dissemination of HR information throughout the company via private company intranets helps employees to handle much of their personal business (e.g. configuring their benefits) themselves, without direct intervention of the HR personnel. • The Internet makes a tremendous amount of information available to the job seeker, increasing the fluidity of the labor market. • IS skills are becoming imperative in many careers – HR professionals must have an understanding of these systems and skills to best support hiring, training, and retention. Trends & Importance of IT
  4. 4. • IT has become a major facilitator of business activities in the world today. • It is also a catalyst of fundamental changes in the structure, operations, and management of organizations. • The capabilities of IT support the following business objectives: – Improving Productivity – Reducing Costs – Improving Decision Making – Enhancing Customer Relationships and improved communication within the organization, and – Developing new strategic applications Impact of Convergence • Telecommunications networks are carrying signals for data, text, video, graphics, and voice • Many services are becoming accessible from home – Banking, Ordering, work at home, News, mail, On-line Education, Medical consultation, Voting. • Cultural impact will be visible – Telecommuting, Cashless Society, Very little town/city differences • E-commerce is emerging a very significant global economic element in the 21st Century • Networked computing is emerging as the standard computing environment in business, home, and Govt. Definition of a Computer “A computer is an electronic device, operating under the control of instructions stored in its own memory unit that can accept data (input); process data arithmetically and logically, produce information (output) from the processing done, and store the results for future use.” Components of Computer System What is the difference between the computer and computer system? Computer refers to the actual physical electronic device. Whereas the computer system includes following: 1. Software – data contained in the hardware, similar to songs in audio cassette. 2. Live ware (user) – the computer operator 3. Hardware – any physical component which we can touch/see. Five Generations of Computers Introduction  The history of computer development is often referred to in reference to the different generations of computing devices.
  5. 5.  Each generation of computer is characterized by a major technological development that fundamentally changed the way computers operate, resulting in increasingly smaller, cheaper, and more powerful and more efficient and reliable devices. First Generation: 1940 – 1956 – Vacuum Tubes  The first computers used vacuum tubes for circuitry, and magnetic drums for memory.  Were often enormous, taking up entire rooms.  Were very expensive to operate and in addition to using great deal of electricity, generated a lot of heat, which was often the cause of malfunctions.  Relied on machine language to perform operations, only one problem at a time.  Input was based on punched cards and paper tape, and output was displayed on printouts.  Very low memory capacities: 2KB – 10KB on magnetic drums.  The UNIVAC and ENIAC computers are examples of first generation computing devices.  The UNIVAC was the first commercial computer delivered to a business client, the U.S. Census Bureau in 1951. Second Generation: 1956 – 1963 – Transistors  Transistors replaced vacuum tubes and ushered in the second generation computers.  The transistor was invented in 1947 but did not see widespread use in computers until the late 1950s.  The transistor was far superior to the vacuum tube, allowing computers to become smaller, faster, cheaper, more energy-efficient and more reliable than their first- generation predecessors.  Though the transistor still generated a great deal of heat that subjected the computer to damage, it was a vast improvement over the vacuum tube.  Second generation computers still relied on punched cards for input and printouts for output.  Programming environment moved from the cryptic binary machine language to symbolic, or assembly language, which allowed the programmers to specify instructions in words and made their task much easier.  High level programming languages were also being developed at this time, such as early versions COBOL and FORTRAN.  The memory technology moved from a magnetic drum to magnetic core technology.  Memory size increased to an order of tens of thousands of Kilobytes.  The first computers of this generation were developed for the atomic energy industry.  Examples: IBM 1400 & 1600 series, Honeywell 400, and Burroughs 5000 series. Third Generation Computers – 1964 – 1971: Integrated Circuits  The development of the integrated circuit was the hallmark of the third generation of computers.
  6. 6.  Transistors were miniaturized and placed on silicon chips, called semiconductors, which drastically increased the speed and efficiency of computers.  Instead of punched cards and printouts, users interacted with third generation computers through keyboards and monitors and interacted with an operating system, which allowed the computer systems to run many different applications simultaneously.  Computers became smaller, faster, more reliable and cheaper. For the first time they became accessible to mass audiences.  Led to massive development of computer programs and application oriented packages.  Increased focus on aspects of data management.  Development of Database Management Systems (DBMS).  IBM 360, 370 series; Univac 1100, 9000 series. Fourth Generation: 1971 – Present Microprocessors  Technology based on VLSI  The Microprocessor brought the fourth generation of computers, as thousands of integrated circuits were built onto a single silicon chip.  What in the first generation filled an entire room could now fit in the palm of the hand.  The Intel 4004 chip, developed in 1971, located all the components of the computer – from the central processing unit and memory to input/output controls on a single chip.  Have massive memory capacity and still growing.  PC computing became available to business community and home users since 1981 with the introduction of PC by IBM. Apple introduced the Macintosh in 1984.  Microprocessors also entered several other areas of life as more and more everyday products began to use them resulting in the convergence of computers and telecommunications.  Computer networks eventually led to the development of Internet.  Development of GUIs, the mouse, and handheld devices.  Web based software development for business and other applications Fifth Generation – Present and Beyond: Artificial Intelligence  Fifth generation computing devices, based on artificial intelligence, are still in development.  Some applications, such as, Voice Recognition, however, are being used today.  The use of Parallel Processing and superconductors is helping to make artificial intelligence a reality.  The goal of fifth-generation computing is to develop devices that respond to natural language input and are capable of learning and self-organization.  Highly networked and parallel architecture based computers.  Focus on Internet and Intranets.  Technology based on VLSI.  Speed reaching billions of instructions per second.  Memory reaching billions of characters in capacity.
  7. 7.  Non-procedural programming environment. Introduction to Computer Hardware • Hardware vs Software Hardware is everything you can touch and see Examples: Monitor, hard drive, CD-ROM, computer cables, keyboard, mouse, modem, printer, etc. Software • Software is a set of instructions that makes the computer perform tasks. • A set of instructions that drive a computer to perform specific tasks is called a program. • These instructions tell the machine’s physical components what to do; without the instructions, a computer could not do anything at all. • When a computer uses a particular program, it is said to be running or executing that program. • Some programs exist primarily for the computer’s use to help it perform tasks and manage its own resources. • Other types of programs exist for the user, enabling him / her to perform tasks such as creating documents or spreadsheets, etc. • Thousands of different software programs are available for use on personal computers. • Most software falls into three major categories: • System Software, Programming Software, and Application Software System Software System Software is the class of programs that control and support a computer system and its information processing activities. It also facilitates the programming, testing and debugging of computer programs. It includes Operating Systems, Compilers, Device Drivers, Diagnostic Tools, Servers, etc. • The purpose of systems software is to insulate the applications programmer as much as possible from the details of the particular computer system being used. There are three major categories of Systems Software: Operating System: An OS supervises the overall operation of the host computer system, including starting the computer, monitoring its status, scheduling operations, and managing all its resources. • An OS is essential for any computer, because it acts as an interpreter between the hardware, application programs, and the user. • Examples include Windows, Linux, Unix, Mac OS A Network Operating System (NOS): It allows computers to communicate and share data across a network while controlling network operations and overseeing the network’s security. Utility: A utility is a program that makes the computer system easier to use or perform highly specialized functions.
  8. 8. • Utilities are used to manage disks, troubleshoot hardware problems, and perform other tasks that the OS itself may not be able to do. Programming Software • It usually provides tools to assist a programmer in writing computer programs and software using different programming languages in a more convenient way. • The tools include – Text editors, Compilers, Interpreters, Linkers, Debuggers, and so on. • An Integrated Development Environment (IDE) merges these tools into a software bundle. IDE generally provides an advanced Graphical User Interface (GUI) facilitating a user to perform his tasks efficiently. Application Software • Application Software tells the computer how to accomplish specific tasks, such as word processing or other applications. • Thousands of applications are available for many purposes and for people of all ages. Some major categories of these applications include: – Word Processing: for creating text based documents. – Spreadsheets: for creating numeric based documents such as budgets or balance sheets. – Database Management Software: for building and manipulating large sets of data. – Presentation Programs: for creating and presenting electronic slide shows. – Graphics Programs: for designing illustrations or manipulating photographs, movies or animations. – Multimedia authoring applications: for building digital movies that incorporate sound, video, animation, and interaction features. – Entertainment and Educational Software: many of which are interactive multimedia events. – Web Design Tools and Web Browsers and other Internet applications such as e-mail programs. – Games: some of which are for a single player and many of which can be played by several people over a network or the Internet. – Industrial Automation, Business Software and Medical Software – Businesses are the biggest users of application software, but almost every field of human activity now uses some form of application software. Components of a Computer • There are four components to a computer – Input Devices – Processor Unit – Output Devices – Auxiliary Storage Devices Input Devices • Input Devices enable the user to enter data into memory • Examples of input devices:
  9. 9. – Keyboard – Mouse – Scanner – Touch Screen Input – OCR The Processor Unit • The Processor Unit is comprised of two components: – Central Processing Unit (CPU) – Memory The Control Process Unit (CPU) • Interprets instructions to the computer • Performs logical and arithmetic operations • Causes the input and output operations to occur • A Pentium Pro Microprocessor can perform approximately 250 million instructions per second (MIPS) CPU TYPES • Intel, Advanced Micro Devices (AMD), Motorola, Cyrix • X86 family of processors: 8080, 8086, 8088, 80286, 80386, 80486, Pentium (P5), Pentium Pro, Pentium II, Pentium IV • MMX - additions to the CPU programming that allow for better and faster multimedia tasks like graphics and sound. Computer Memory • RAM - Random Access Memory – Computer’s primary storage of data to be processed – Silicon chips that store data and instructions as electronic currents – CPU can manipulate electrical currents – Contents of RAM will be lost when power is turned off • Usually measured in MB or KB (e.g.: 8 MB of RAM) • 1000 KB approximately = 1 MB • 1 MB contains approximately 500 pages of text information. • More RAM = faster processing rate • Applications determine how much RAM needed ROM - Read Only Memory – Instructions and data are hard coded on the silicon chips – Examples: BIOS (Basic Input-Output System) • Gives computer the initial instructions to get it started once computer is turned on. Cache • Temporary holding area where the system stores frequently accessed information • Allows the processor to operate faster • Size measured in KB (e.g. 256K or 512 K) • Cache associated with the terms L1 or L2
  10. 10. • L1 is internal to the microprocessor • L2 is separate from the microprocessor Output Devices • Output Devices make the information resulting from processing available for use • Examples of Output Devices: – Printers – Computer Screens – Speakers Computer Screens • Also called monitor or Cathode Ray Tube (CRT) • Flat panel screens - LCD (Liquid Crystal Display) • Screen is made up of pixels Auxiliary Devices • Also know as Secondary Storage Devices • Examples of Auxiliary Devices: – Floppy Disks – Hard Drives – CD-ROM – Tape Backup Drives – ZIP Drives Floppy Disks • Two Types of floppy drives – 1.2 MB 5.25” – 1.44 MB 3.5” • Advantages – Inexpensive – Portable • Disadvantages – Slow access time – Low capacity • Access time is measured in milliseconds (ms) • Formatting and protecting floppy disks Hard Disks • Secondary Storage Device • Able to store large amounts of data • Internal vs External • Storage measured in MB’s or GB’s • Access time measured in milliseconds (9-28 ms) • Compression programs are used to save storage space CD-ROM
  11. 11. • Compact disk read-only memory disks are used to store large amounts of prerecorded information • Since programs are getting bigger, it is a good medium for storage of programs • Drive Speeds: 4X, 6X, 8X, 10X, 16X, 20X, 24X • Read-Write CD’s are now available Monitor • Measured diagonally in inches • Actual viewable area is less • Monochrome – Black and white display • Color Monitors – SVGA, VGA, EGA, CGA: • Image consists of small dots or pixels • More pixels = clearer image • Monitor needs monitor controller (Video/Monitor card) to function – Memory on monitor controller accelerates display on image – Accelerator chip speeds up display as well End-user computing End User Computing (EUC) is a group of approaches to computing that aim at better integrating end users into the computing environment or that attempt to realize the potential for high-end computing to perform in a trustworthy manner in problem solving of the highest order. The EUC Ranges section describes two types of approaches that are at different ends of a spectrum. A simple example of these two extremes can use theSQL context. and php The first approach would have canned queries and reports that for the most part would be invoked with buttons and/or simple commands. In this approach, a computing group would keep these canned routines up to date through the normal development/maintenance methods. For the second approach, SQL administration would allow for end-user involvement at several levels including administration itself. Users would also define queries though the supporting mechanism may be constrained in order to reduce the likelihood of run-away conditions that would have negative influence on other users. We see this already in some business intelligence methods which build SQL, including new databases, on the fly. Rules might help dampen effects that can occur with the open-ended environment. The process would expect, and accommodate, the possibility of long run times, inconclusive results and such. These types of unknowns are undecidable 'before the fact'; the need to do 'after the fact' evaluation of results is a prime factor of many higher-order computational situations but cannot (will not) be tolerated by an end user in the normal production mode.
  12. 12. Structured Program Development Introduction • Before writing a program: – Have a thorough understanding of the problem – Carefully plan an approach for solving it • While writing a program: – Know what “building blocks” are available – Use good programming principles Algorithms • Computing problems – All can be solved by executing a series of actions in a specific order • Algorithm: procedure in terms of – Actions to be executed – The order in which these actions are to be executed • Program control – Specify order in which statements are to executed Pseudocode • Pseudocode – Artificial, informal language that helps us develop algorithms – Similar to everyday English – Not actually executed on computers – Helps us “think out” a program before writing it • Easy to convert into a corresponding C++ program • Consists only of executable statements Control Structures • Sequential execution – Statements executed one after the other in the order written • Transfer of control – When the next statement executed is not the next one in sequence – Overuse of goto statements led to many problems • Bohm and Jacopini – All programs written in terms of 3 control structures • Sequence structures: Built into C. Programs executed sequentially by default • Selection structures: C has three types: if, if/else, and switch • Repetition structures: C has three types: while, do/while and for • Flowchart – Graphical representation of an algorithm – Drawn using certain special-purpose symbols connected by arrows called flowlines – Rectangle symbol (action symbol): • Indicates any type of action – Oval symbol: • Indicates the beginning or end of a program or a section of code
  13. 13. • Single-entry/single-exit control structures – Connect exit point of one control structure to entry point of the next (control-structure stacking) – Makes programs easy to build The if Selection Structure • Selection structure: – Used to choose among alternative courses of action – Pseudocode: If student’s grade is greater than or equal to 60 Print “Passed” • If condition true – Print statement executed and program goes on to next statement – If false, print statement is ignored and the program goes onto the next statement – Indenting makes programs easier to read • C ignores whitespace characters • Pseudocode statement in C: if ( grade >= 60 ) printf( "Passedn" ); – C code corresponds closely to the pseudocode • Diamond symbol (decision symbol) – Indicates decision is to be made – Contains an expression that can be true or false – Test the condition. • if – Only performs an action if the condition is true • if/else – Specifies an action to be performed both when the condition is true and when it is false • Psuedocode: If student’s grade is greater than or equal to 60 Print “Passed” else Print “Failed” – Note spacing/indentation conventions • C code: if ( grade >= 60 ) printf( "Passedn"); else printf( "Failedn"); • Ternary conditional operator (?:) – Takes three arguments (condition, value if true, value if false) – Our pseudocode could be written:
  14. 14. printf( "%sn", grade >= 60 ? "Passed" : "Failed" ); – Or it could have been written: grade >= 60 ? printf( “Passedn” ) : printf( “Failedn” ); The while Repetition Structure • Repetition structure – Programmer specifies an action to be repeated while some condition remains true – Psuedocode: While there are more items on my shopping list Purchase next item and cross it off my list – while loop repeated until condition becomes false • Counter-controlled repetition – Loop repeated until counter reaches a certain value – Definite repetition: number of repetitions is known – Example: A class of ten students took a quiz. The grades (integers in the range 0 to 100) for this quiz are available to you. Determine the class average on the quiz – Pseudocode: Set total to zero Set grade counter to one While grade counter is less than or equal to ten Input the next grade Add the grade into the total Add one to the grade counter Set the class average to the total divided by ten Print the class average Problem becomes: Develop a class-averaging program that will process an arbitrary number of grades each time the program is run. – Unknown number of students – How will the program know to end? Use sentinel value – Also called signal value, dummy value, or flag value – Indicates “end of data entry.” – Loop ends when user inputs the sentinel value – Sentinel value chosen so it cannot be confused with a regular input (such as -1 in this case) • Top-down, stepwise refinement – Begin with a pseudocode representation of the top: Determine the class average for the quiz – Divide top into smaller tasks and list them in order:
  15. 15. Initialize variables Input, sum and count the quiz grades Calculate and print the class average • Many programs have three phases: – Initialization: initializes the program variables – Processing: inputs data values and adjusts program variables accordingly – Termination: calculates and prints the final results • Refine the initialization phase from Initialize variables to: Initialize total to zero Initialize counter to zero • Refine Input, sum and count the quiz grades to Input the first grade (possibly the sentinel) While the user has not as yet entered the sentinel Add this grade into the running total Add one to the grade counter Input the next grade (possibly the sentinel) • Refine Calculate and print the class average to If the counter is not equal to zero Set the average to the total divided by the counter Print the average else Print “No grades were entered” Nested control structures: • Problem – A college has a list of test results (1 = pass, 2 = fail) for 10 students – Write a program that analyzes the results • If more than 8 students pass, print "Raise Tuition" • Notice that – The program must process 10 test results • Counter-controlled loop will be used – Two counters can be used • One for number of passes, one for number of fails – Each test result is a number—either a 1 or a 2 • If the number is not a 1, we assume that it is a 2 • Top level outline Analyze exam results and decide if tuition should be raised • First Refinement Initialize variables Input the ten quiz grades and count passes and failures Print a summary of the exam results and decide if tuition should be raised • Refine Initialize variables to Initialize passes to zero Initialize failures to zero Initialize student counter to one
  16. 16. • Refine Input the ten quiz grades and count passes and failures to While student counter is less than or equal to ten Input the next exam result If the student passed Add one to passes else Add one to failures Add one to student counter • Refine Print a summary of the exam results and decide if tuition should be raised to Print the number of passes Print the number of failures If more than eight students passed Print “Raise tuition” Assignment Operators: • Assignment operators abbreviate assignment expressions c = c + 3; can be abbreviated as c += 3; using the addition assignment operator • Statements of the form variable = variable operator expression; can be rewritten as variable operator= expression; • Examples of other assignment operators: d -= 4 (d = d - 4) e *= 5 (e = e * 5) f /= 3 (f = f / 3) g %= 9 (g = g % 9) Increment and Decrement Operators: • If c equals 5, then printf( "%d", ++c ); – Prints 6 printf( "%d", c++ ); – Prints 5 – In either case, c now has the value of 6 • When variable not in an expression – Preincrementing and postincrementing have the same effect ++c; printf( “%d”, c ); – Has the same effect as c++;
  17. 17. printf( “%d”, c );