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UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS
                               General Certificate of Education
                               Advanced Subsidiary Level and Advanced Level



               COMPUTING                                                                                              9691/01
               Paper 1                                                                             October/November 2007
                                                                                                        2 hours 30 minutes
               Additional Materials:     Answer Booklet/Paper
*7683472067*




               READ THESE INSTRUCTIONS FIRST

               If you have been given an Answer Booklet, follow the instructions on the front cover of the Booklet.
               Write your Centre number, candidate number and name on all the work you hand in.
               Write in dark blue or black pen.
               You may use a soft pencil for any diagrams, graphs or rough working.
               Do not use staples, paper clips, highlighters, glue or correction fluid.

               Answer all questions.

               At the end of the examination, fasten all your work securely together.
               The number of marks is given in brackets [ ] at the end of each question or part question.




                                                This document consists of 4 printed pages.

               IB07 11_9691_01/5RP
               © UCLES 2007                                                                                       [Turn over




                                               www.xtremepapers.net
2

1   (a) (i) Describe a GUI (Graphical User Interface).                                           [2]

        (ii) Describe a form-based computer interface.                                           [2]


    (b) (i) State a computer application for which a GUI would be suitable. Justify your answer. [2]

        (ii) State a computer application for which a form-based interface would be suitable.
             Justify your choice.                                                                [2]


    (c) A computerised information system is set up in a busy town centre.
        The system gives details of transport, shops, sales of goods, places to eat and hotels.
        Describe the hardware and the software of the HCI (Human Computer Interface) giving
        reasons for your answers.                                                               [4]


2   A variety of goods are stored in a warehouse.
    All goods enter and leave the warehouse at a specific point.
    All goods are bar coded.

    (a) The number of each item in the warehouse is stored as a binary number.
        Change 83 into a binary number stored in an 8 bit byte.                                  [2]

    (b) The warehouse uses stock control software.
        Explain how this software maintains stock levels in the warehouse.                       [5]


3   (a) State one difference between random access memory (RAM) and read only memory (ROM).
                                                                                        [1]


    (b) State three types of data stored in RAM.                                                 [3]


    (c) An embedded processor contains all the software needed to control an automatic washing
        machine.

         (i) State why the software is stored on ROM.                                            [1]

        (ii) Explain why it is important that ROM has some of the characteristics of RAM.        [2]


4   (a) Give four points that need to be considered when a systems analyst produces a feasibility
        study.                                                                               [4]


    (b) Describe what is involved in the analysis stage of the systems development life cycle.   [6]


5   Explain why personal data, held about members of the public on computer systems, needs to be
    protected. State measures which can be used to protect this data.                         [6]




© UCLES 2007                                 9691/01/O/N/07



                              www.xtremepapers.net
3

6   A washing machine is computer controlled.
    The full cycle consists of
       •      Check the door is shut
       •      Heat water with heater (H) to 80 degrees if hot wash has been selected, 40 degrees if a
              cool wash has been selected
       •      Run wash motor (M) for 20 minutes, checking water every 5 minutes to see if heater (H)
              should be turned on again
       •      Sound buzzer to signify that wash cycle is complete.
    Note: M can be set to “on” or “off”.

    Write an algorithm, in whatever form, to show the working of the washing machine.                 [7]


                   The remaining questions refer to the following information.

    A company specialises in surveying land for oil companies.
    Part of their work involves using radar and other scientific procedures to search underground for
    likely oil-bearing formations. The results of the surveys are stored numerically, ready for
    processing.


7   Data collected during the search is input to a knowledge based (expert) system.

    (a) Describe three parts of a knowledge based system.                                             [6]

    (b) Explain how this knowledge based system was set up and how it is used.                        [5]


8   Data collected at the survey site is sent, electronically, to the head office of the company for
    processing.

    (a) Describe the hardware necessary to enable this communication.                                 [3]

    (b) (i) The results of the analysis of the data are often output on a plotter.
            Give two advantages of outputting this data to a plotter.                                 [2]

        (ii) Apart from the output to the plotter, the system produces many other output formats.
             State two forms of output which would be produced by this application and explain why
             each is appropriate.                                                               [4]


9   (a) Describe what is meant by taking

         (i) a backup of data,                                                                        [2]

        (ii) an archive of data.                                                                      [2]

    (b) The data collected by the survey teams and the results of the processing are both backed up
        and archived.

         (i) Explain why it would be important to take a back up of the results of a survey.          [2]

        (ii) Explain why it would be important to archive the results of a survey.                    [2]




© UCLES 2007                                  9691/01/O/N/07                                   [Turn over


                              www.xtremepapers.net
4

10 (a) Much of the processing of the data is carried out using a spreadsheet.
       Explain why the features of spreadsheet software would be useful for processing this data. [3]

      (b) The results of surveys carried out must be presented to the oil company that has
          commissioned them. This is normally done at a special meeting with the managers of the
          company.
          Explain the features of presentation software which make it appropriate for use in this
          situation.                                                                          [2]


11 The data which is transmitted between survey sites and head office is liable to errors. Data which
   is received is checked for errors.

      (a) One method of checking for errors is to use parity checks.
          The following four bytes have been received:

                                        01101001            10111100             10101010            00100100

             (i) One of the bytes contains an error. State which byte.                                                                                   [1]

            (ii) Explain your choice of answer in (i).                                                                                                   [2]

           (iii) Explain why a byte may still be in error even if it passes the parity test.                                                             [1]

      (b) A second method of checking for errors is to use check sums.
          Explain how check sums are used to check data for transmission errors.                                                                         [4]




Permission to reproduce items where third-party owned material protected by copyright is included has been sought and cleared where possible. Every
reasonable effort has been made by the publisher (UCLES) to trace copyright holders, but if any items requiring clearance have unwittingly been included, the
publisher will be pleased to make amends at the earliest possible opportunity.

University of Cambridge International Examinations is part of the Cambridge Assessment Group. Cambridge Assessment is the brand name of University of
Cambridge Local Examinations Syndicate (UCLES), which is itself a department of the University of Cambridge.

© UCLES 2007                                                         9691/01/O/N/07



                                              www.xtremepapers.net

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Nov 07 P1

  • 1. UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS General Certificate of Education Advanced Subsidiary Level and Advanced Level COMPUTING 9691/01 Paper 1 October/November 2007 2 hours 30 minutes Additional Materials: Answer Booklet/Paper *7683472067* READ THESE INSTRUCTIONS FIRST If you have been given an Answer Booklet, follow the instructions on the front cover of the Booklet. Write your Centre number, candidate number and name on all the work you hand in. Write in dark blue or black pen. You may use a soft pencil for any diagrams, graphs or rough working. Do not use staples, paper clips, highlighters, glue or correction fluid. Answer all questions. At the end of the examination, fasten all your work securely together. The number of marks is given in brackets [ ] at the end of each question or part question. This document consists of 4 printed pages. IB07 11_9691_01/5RP © UCLES 2007 [Turn over www.xtremepapers.net
  • 2. 2 1 (a) (i) Describe a GUI (Graphical User Interface). [2] (ii) Describe a form-based computer interface. [2] (b) (i) State a computer application for which a GUI would be suitable. Justify your answer. [2] (ii) State a computer application for which a form-based interface would be suitable. Justify your choice. [2] (c) A computerised information system is set up in a busy town centre. The system gives details of transport, shops, sales of goods, places to eat and hotels. Describe the hardware and the software of the HCI (Human Computer Interface) giving reasons for your answers. [4] 2 A variety of goods are stored in a warehouse. All goods enter and leave the warehouse at a specific point. All goods are bar coded. (a) The number of each item in the warehouse is stored as a binary number. Change 83 into a binary number stored in an 8 bit byte. [2] (b) The warehouse uses stock control software. Explain how this software maintains stock levels in the warehouse. [5] 3 (a) State one difference between random access memory (RAM) and read only memory (ROM). [1] (b) State three types of data stored in RAM. [3] (c) An embedded processor contains all the software needed to control an automatic washing machine. (i) State why the software is stored on ROM. [1] (ii) Explain why it is important that ROM has some of the characteristics of RAM. [2] 4 (a) Give four points that need to be considered when a systems analyst produces a feasibility study. [4] (b) Describe what is involved in the analysis stage of the systems development life cycle. [6] 5 Explain why personal data, held about members of the public on computer systems, needs to be protected. State measures which can be used to protect this data. [6] © UCLES 2007 9691/01/O/N/07 www.xtremepapers.net
  • 3. 3 6 A washing machine is computer controlled. The full cycle consists of • Check the door is shut • Heat water with heater (H) to 80 degrees if hot wash has been selected, 40 degrees if a cool wash has been selected • Run wash motor (M) for 20 minutes, checking water every 5 minutes to see if heater (H) should be turned on again • Sound buzzer to signify that wash cycle is complete. Note: M can be set to “on” or “off”. Write an algorithm, in whatever form, to show the working of the washing machine. [7] The remaining questions refer to the following information. A company specialises in surveying land for oil companies. Part of their work involves using radar and other scientific procedures to search underground for likely oil-bearing formations. The results of the surveys are stored numerically, ready for processing. 7 Data collected during the search is input to a knowledge based (expert) system. (a) Describe three parts of a knowledge based system. [6] (b) Explain how this knowledge based system was set up and how it is used. [5] 8 Data collected at the survey site is sent, electronically, to the head office of the company for processing. (a) Describe the hardware necessary to enable this communication. [3] (b) (i) The results of the analysis of the data are often output on a plotter. Give two advantages of outputting this data to a plotter. [2] (ii) Apart from the output to the plotter, the system produces many other output formats. State two forms of output which would be produced by this application and explain why each is appropriate. [4] 9 (a) Describe what is meant by taking (i) a backup of data, [2] (ii) an archive of data. [2] (b) The data collected by the survey teams and the results of the processing are both backed up and archived. (i) Explain why it would be important to take a back up of the results of a survey. [2] (ii) Explain why it would be important to archive the results of a survey. [2] © UCLES 2007 9691/01/O/N/07 [Turn over www.xtremepapers.net
  • 4. 4 10 (a) Much of the processing of the data is carried out using a spreadsheet. Explain why the features of spreadsheet software would be useful for processing this data. [3] (b) The results of surveys carried out must be presented to the oil company that has commissioned them. This is normally done at a special meeting with the managers of the company. Explain the features of presentation software which make it appropriate for use in this situation. [2] 11 The data which is transmitted between survey sites and head office is liable to errors. Data which is received is checked for errors. (a) One method of checking for errors is to use parity checks. The following four bytes have been received: 01101001 10111100 10101010 00100100 (i) One of the bytes contains an error. State which byte. [1] (ii) Explain your choice of answer in (i). [2] (iii) Explain why a byte may still be in error even if it passes the parity test. [1] (b) A second method of checking for errors is to use check sums. Explain how check sums are used to check data for transmission errors. [4] Permission to reproduce items where third-party owned material protected by copyright is included has been sought and cleared where possible. Every reasonable effort has been made by the publisher (UCLES) to trace copyright holders, but if any items requiring clearance have unwittingly been included, the publisher will be pleased to make amends at the earliest possible opportunity. University of Cambridge International Examinations is part of the Cambridge Assessment Group. Cambridge Assessment is the brand name of University of Cambridge Local Examinations Syndicate (UCLES), which is itself a department of the University of Cambridge. © UCLES 2007 9691/01/O/N/07 www.xtremepapers.net