State four threats that compromise data integrity

• Human error
• natural disaster
• data transmission errors
• software bugs

How threats to data integrity can be minimised:

• Backup data preferably on an external storage media
• control access to data by enforcing security measures
• design user interfaces that minimise chances of invalid data entry
• using error detection and correction software when transmitting data over the network
• using devices that directly capture data from the source such as bar code readers, digtal cameras, and optical character readers

Shielded twisted pair cable:
A twisted pair cable is made up of four pairs of twisted copper wires, a shielded twisted pair cable applies a shield to each one of the pairs on a cable or to all of the pairs together. This shield can reduce EMI (electromagnetic interference), which would be emitted from heavy machinery. This increased data transmission quality in the workshop. STP can also reduce crosstalk.

• The number of FDE cycles run per given time/second
• the frequency that the clock ‘ticks’
• 3.8 billion cycles/instructions per second

• Editor: this allows a programmer to enter and edit source code
• Automatic formatting:  Correctly indents code
• Automatic colour coding:  Changes key words, literals and annotation to different colours
• Linker: this is a program which allows previously compiled code, from software libraries, to be linked together
• Loader: this is a program which loads previously compiled code into memory.
• Debugger: this is a program which helps locate, identify and rectify errors in a program
• Syntax error detection:  Highlighting syntax errors before code is translated
• Trace: this is a facility which displays the order in which the lines of a program are executed, and possibly the values of variables as the program is being run
• Break point: this is a facility which interrupts a program on a specific line of code, allowing the programmer to compare the values of variables against expected values.  The program code can then usually be executed one line at a time.  This is called single-stepping
• Variable watch: this is a facility which displays the current value of any variable.  The value can be 'watched' as the program code is single-stepped to see the effects of the code on the variable.  Alternatively a variable watch may be set, which will interrupt the program flow if the watched variable reaches a specified value
• Memory inspector: this is a facility which will display the contents of a section of memory
• Error diagnostics: these are used when a program fails to compile or to run.  Error messages are displayed to help the programmer diagnose what has gone wrong
• Emulator: will provide and emulator to run the code/app so no physical device required
• Context sensitive menu:  SDE suggests available options
• Statement completion:  SDE will complete a statement such as adding an ‘end if’ to an ‘if’ statement GUI creation:  Allows programmer to create a GUI by dragging and dropping controls (buttons, etc...) onto a form.
• Publisher: facility to package up and deploy program as an easy to install package

• To provide legal backing so that it is possible to seek redress if the rights are violated
• To observe copyright for those who create original works
• To protect the confidentiality of information kept  about an individual

• (Cache) Stores regularly accessed instructions/data
• Reduces the need to access instructions/data from the main memory
•  Makes up for the difference in speed of the CPU and main memory

 Control unit

• more accurate/improved stock control/recording system/automatic
• reordering/automatic updating of stock file
• less staff/wages needed
• sales statistics now available
• faster throughput
• itemised receipt
• records every transaction
• records staff work rates
• less pilfering by staff/easier to identify pilfering
• less errors
• faster calculations
• links to EFTPOS

• A barcode is one-dimensional while a QR code is two dimensional
• Barcodes are a set of vertical lines and QR code contains squares
• QR codes can be read from any angle . Barcode is only above or below and lined up horizontally

• It refers to a computer that controls other computers in a network and monitors user's access to the shared resources.

State four advantages for using a graphical user interface in loading programs and files

• User friendly
• No need to know command language as commands are executed by clicking on icons
• Allows multitasking as several programs open at the same time therefore easier to switch between applications
• Selecting an item using a mouse is easier and faster than entering commands

Or any other correct response

Advantage @ 1 Mark

Total = 4 X 1 Mark

= 4 Marks

A vehicle assembly company has introduced robots to replace the human workforce.  State two effects this would have on the workforce                

• Unemployment
• Need to retrain
• No longer need to do hazardous or tedious jobs
• Employment of skilled staff who will manipulate the robots

Or any other correct response

Effect @ 1 Mark

Total = 2 X 1 Mark

= 2 Marks

• Refers to the scrambling of data into unreadable form before transmission over a telecommunication media  OR
• transformation of data from plaintext to ciphertext

– faster communications now widely available
– safety reasons, e.g. increase in terrorist attacks on international flights
– reduced transportation/accommodation/hardware costs
– environmental issues, e.g. reduced carbon footprint
– increase in multinational working

• Real time  E.g. turning the wheel must turn the car immediately
• On line - Otherwise system cannot be real time

• deskilling – software has removed the need for some of the more traditional skills e.g. using CAD
• (re-)training – work practices have changed; need to learn how to use the new software/computer
• redundancy – new technology allows work to be completed by fewer staff/out-sourced to “cheaper” work forces in foreign countries
• work from home (etc.) – use of emails, VoIP, video conferencing, instant messaging, etc. allows working away from the office
• – nicer/safer workplace – quieter (no noisy typewriters) and safer (no heavy filing cabinets)
• – health (& safety) – RSI, headaches, backaches

• The preparation of a system proposal which lists the problem definition, objectives of the study, terms of reference of study, constraints, and expected benefits of the new system, in light of the user requirements

SECTION A (40 MARKS)

1.What is meant by

    a)Analogue data

     b)Digital data                           (4 mks)

2. Distinguish between transcription and transposition types of errors and give an example of each  (4mks)

3. a)What are peripheral devices?  (1mk)

   b)Give two examples of peripheral devices  (1mk)

4a)What meant by the term user-friendly as used in software development? (1mk)

  b)Distinguish between the terms single-tasking and multi-user as used in operating systems  (2mks)

5.What actions should be taken in case of a fire outbreak in the computer laboratory?  (4mks)

6a) What is an Internet Service Provider?    (1mk)

  b) An employee in a business company is charged with the responsibility of putting the company advertisements on the Internet.

 i) State the professional title of the employee. (1mk)

ii) Give an example of software used by this employee to carry out the above task.    (1mk)

7.Differentiate between COM ports and LPT ports     (2mks)

8.Explain two ways in which ICT can enhance commerce.  (2mks)

9. Explain the following software terms:

    a) Portability       (1 mk)

    b) Modularity      (1 mk)

10. a) State two application areas of desktop publishing software. (2mks)

     b) Explain the following graphic terms:                                                                                     

     i) Rotate (1 mk)

    ii) Crop  (1mk)

12. a)List two arithmetic operations that can be performed on a row of numeric data in a word processing table.    (1 mk)

     b) In each case of (a) above, write the expression used.  (2mks)

13. List two methods of gathering information during the system development process   (2mks)

14.Name three types of optical disks.(3mks)

15.The diagram below shows a formatted plate surface of a storage disk.

            Shade and label:

            a)         one sector                                                                                ( 1mk)

            b)         One block                                                                                (1mk)

SECTION B (60 MKS)

Answer question 16 and any other three questions from this section in the  space provided

16 a) List two examples of:

       i) Third generation languages    (2mks)

       ii) Object oriented languages    (2 mks)

b) Draw a flowchart to compare three non-equal numeric values A, B, C and prints the largest of the three. (11 mks)

17 a) One of the functions of an operating system is job scheduling.  Explain what is meant by job scheduling.   (1mk)

    b)List and explain three types of user interfaces.                      (6 mks)

    c)Describe the following categories of software:

       i) Firmware                 (1mk)

       ii) Proprietary software  (1mk)

     d) a new company XYZ intends to go into the business of desktop publishing. Advise the company on three computer hardware system specification features to consider as a measure of enhancing performance. (6 mks)

18. a) distinguish between the following sets of terms as used in spreadsheets.        (2mks)

     i)Worksheet and workbook

     ii) Filtering and sorting

     b) State one way in which a user may reverse the last action taken in a spreadsheet package.        (1 mk)

     c)The following is a sample of a payroll. The worksheet row and column headings are marked  1, 2, 3, .  and A, B, C.  respectively