2006 HSC Paper - Section III

Section III of the 2006 HSC Paper consists of 4 option topic questions with sub-questions a, b and c, with a and b divided into sub-questions i and ii. Only two of these questions must be answered, the option topics covered here being Transaction Processing Systems and Multimedia Systems. This page provides answers to each question and a reference that can justify each answer (some questions do not have reference as references have not been located). As such, this page is best used in conjunction with the paper open in a separate window or tab.

References follow the following format:
 * [source] page number/url


 * [1] Refers to 'Information Processes and Technology HSC Course' by Peter Ware + Paul Cheleski + Bill Chivers
 * [2] Refers to 'Information Processes and Technology HSC Course' (2007), by Sam Davis
 * [3] Refers to 'Information Processes and Technology The Preliminary Course' (2004), by Sam Davis
 * [4] Refers to non-textbook resources such as websites.

Question 25a(i)

 * A transaction is where data is collected, stored, retrieved and modified. It can be an exchange of goods and services. A transaction can be an electronic transaction or a manual transaction.
 * An example of a transaction in a library is the borrowing of a book. The book is scanned (collected), the data is retrieved, the book is checked out to a student and the modified data is stored in the library’s database.
 * An example of a transaction in a library is the returning of a book. The book is scanned (collected), the data is retrieved, the book is checked as returned and the modified data is stored in the library’s database.
 * An example of a transaction in the library is the search for a book. The student inputs the name of the book, title or author, presses the ‘search’ button and the book(s) is displayed on the screen. While the data in the database has not been modified, the data on the screen has been modified.
 * An example of a transaction is the payment of money to the librarian to ‘top up’ a student’s card to allow photocopying.
 * An example of a transaction in the library is the deposit of money into a photocopier to obtain photocopies.
 * An example of a transaction in the library is the purchase of a book by exchanging money for the book.

Question 25a(ii)
Two features of an online form to enable data collection may include:
 * Text boxes where data is inputted by the user
 * A connection to an online database
 * Text boxes are connected to respective fields with an online database
 * Use of pull down menus to minimise input error. Data entry may be slower but the accuracy will be greater
 * Use of radio buttons to choose between two alternatives
 * Use of text to give directions to the user
 * Use of a submit button to transmit the collected data to the online database.
 * Use of range checks to minimise input error e.g. Checking the range of postcodes within Australia
 * Use of input masks to encourage the correct format of data e.g. Birthdate or phone numbers
 * Use of default values within a field.
 * Use of symbols that indicate a mandatory field

Question 25b(i)

 * Batch processing refers to the gathering of a group of transactions, over a period of time, and then processing these transactions at a designated time.
 * Real time processing refers to processing that takes place immediately.
 * 1) Real time processing takes place when the voter’s name is marked off the roll.
 * 2) Validation of the card is real time processing.
 * 3) The data entry of each field is real time processing. The collecting of all the fields may be considered as batch because the data is not transmitted until the voter confirms their choices.
 * 4) The confirmation of the second swipe of the card is real time processing.
 * 5) The transmitting of the vote to a virtual ballot box on the server is real time processing (but the fields were entered as a batch).
 * 6) The transmitting of all the ballot box servers to a central computer is batch processing.

Question 24b(ii)
Storing and retrieving involves saving data and information for use (storing) and obtaining data and information that has been previously saved (retrieving).

Some security measures that could be used in the EVACS system include:
 * Use of a firewall to restrict or close commonly used ports. This helps to prevent hackers from obtaining access to the system. This would have impact upon transmitting data and receiving data.
 * Use of encryption and decryption techniques during transmission eg. Asymmetrical encryption which requires a key for encryption and a key for decryption. A public key is used to encrypt, a private key is used to decrypt.
 * The data within the database could be encrypted as well. If hackers actually broke into the database, they would only read symbols that would not make sense.
 * The use of passwords would be another measure. Passwords would be assigned to authorised personnel that would allow different levels of access to the database. Supervisors may have partial access to the database while the Officer in Charge may have full access to the database.
 * Backing up the data could be another measure. One could use the Grandfather, father and son strategy, inferential or differential strategy to backup the database. One could mirror the database as well.
 * The backups should be stored off site in case of some disaster such as fire or flood. This would allow for easy restoration of the data.
 * The servers on which the databases are stored should be placed in a secure room where physical locks may exist or biometric devices are used to gain entry by authorised personnel.

Question 25c
Some of the issues that might arise if SMS were used for future parliamentary elections: The above points predict and explain many of the issues that need to be dealt with if SMS voting was to take place in future parliamentary elections.
 * The design of the interface. Different phones have different screen sizes and a different number of pixels. Some screens are mono whilst others are coloured. People with poor eyesight may have difficulty in seeing the screen. Perhaps larger fonts can be used for people with poor eyesight. A voting sheet normally has several choices offered. A phone screen at present could not hope to offer all choices on one screen. This means that more than one screen would have to be used, and the screen would have to be interactive.
 * As mentioned previously, people with poor eyesight may have difficulty seeing the screen. Many elderly people do not use mobile phones, hence, they could not use this system. Many elderly people may not be able to afford the costs of SMS messaging, especially if ‘interactiveness’ was required and a charge was incurred for every screen of data. Elderly people may need training in the use of SMS and voting.
 * A phone may be stolen and the thief may enter an incorrect vote.
 * Many people may vote from one phone, hence, each voter would have to be issued with a unique username and password, most probably through snail mail.
 * Since voting would take place during a tight time frame (e.g. 8 hours), the SMS network may become too congested and some SMS votes may never reach the appropriate destination.
 * Confirmation of a recorded vote would have to be sent back to the mobile SMS device so that the voter would be confident his / her vote was actually recorded.
 * SMS and mobile phones use wireless technology which is susceptible to hackers. Hackers could intercept the vote and change the vote before it was allowed to go onto its destination. Encryption and decryption may overcome this difficulty.
 * People under the age of 18 may vote illegally.
 * People from other countries may try to vote in future parliamentary elections. Again, the assignment of a username and password may overcome this predicted difficulty.
 * The mobile phone may run out of battery power whilst voting.
 * Perhaps specific SIMM cards can be assigned to each voter for the SMS voting process.
 * Mobile phones cannot access a mobile network in many country areas. The future voting system would need to make the signal available all over the country.

Question 28a(i)
A realistic simulation of an environment, including three-dimensional graphics, by a computer system using interactive software and hardware. Example: Heads up display (such as those found in Wii devices).

(Multimedia Systems) [1] 282

Question 28a(ii)
Flight simulators are an example of simulation use in education and training as they mimic the conditions felt whilst piloting a plane, allowing users to practice flying a plane in a controlled environment. The inside of the simulated plane resembles a real aircraft cockpit, allowing users to get a grasp of the controls and procedures in a plane without the risk of flying a real aircraft. (Multimedia Systems) [1] p282

Question 28b(i)
The main technologies used by Navmap for display include;
 * Colour LCD display to display graphical information. An LCD is required to reduce the physical size of the screen to a size suitable for a portable device.
 * Speakers so that voice directions and music can be heard.
 * Software to display the images on the screen and to send the audio to the speakers.
 * GPS telecommunication to collect information from satellites about the location of the car so that the device can provide the correct maps to display on the screen.

Question 28b(ii)
Images can be compressed using a lossless compression, such as gif, where the data is analysed and repeated data is replaced with code that is smaller than the original, but when it is displayed the original data is restored, providing no loss of quality. Images can also be compressed using a lossy technique, such as jpeg, that reduces the amount of data to be stored by removing changes in the data that the human eye wouldn’t be able to detect, such as variations in colour, and when it is displayed, there is a slight decrease in quality. The reduction in file size is important to the Navmap device because graphics file sizes can be very large and there would be limited storage ability in small devices. Compression could reduce the file size dramatically and this would also allow the Navmap device to load pictures more quickly. Similarly, sound files can be large and need to be compressed. Frequencies that are not able to be detected by the human ear are removed, thus reducing the amount of data to be stored. Other methods of reducing an audio file size may also be considered before a compression algorithm is used. Reducing the sample rate in recording, or recording in mono rather than stereo would also achieve a reduction in the file size.

Question 28c
Traditional maps and Navmap both provide the user with the ability to navigate and plan a trip; however the method of navigation and planning would be very different. To use traditional maps the user would require some map reading ability to locate where they are, where they are going and the most efficient route between them. Navmap on the other hand may eliminate most of the map reading skills such as locating positions on a map and finding a route between them, but some skill in reading the map, similar to a paper map, may be useful. The street directories and paper maps, which have been traditional navigational aids, may become redundant and in a small way this may be better for the environment.

The information provided to the user of Navmap will be similar to that provided by a traditional map and in many ways this information may be more useful. The Navmap will provide the user with directions, which eliminates the need for a second person to navigate or the driver to stop frequently to reorientate them and remember the next few steps in the journey. On the other hand, the driver may have local knowledge about traffic conditions or known traffic delays that the Navmap wouldn’t be aware of and this information may allow the driver to find a more efficient route using traditional maps in some circumstances.

The quality of the information provided by the Navmap should be similar to he traditional maps, as the Navmap is simply an electronic version of the traditional map. The advantages that Navmap will have over paper-based maps include the ability to have updated versions downloaded to the device, the voice directions to ensure correct navigation without missing turns or getting lost and the ability of the GPS function to always pinpoint their location so you don’t have to find where you are on a map. A person navigating using traditional maps has the ability to make detours from the planned route, they may wish to visit a tourist site they see marked on the map, but is not visible or obvious on the Navmap, as a traditional map provides the user with a wider overview of the area in which they are travelling. The traditional map would still be needed in areas where there is poor satellite coverage or if the communication link becomes inactive.

Navmap, which has all the maps for Australia installed, allows the user to travel anywhere in Australia without the need to purchase new maps or street directories, which may be an advantage for people undertaking long journeys. Overall, Navmap is likely to provide the user with more accurate information about their journey, provide detailed voice directions to ensure the user doesn’t get lost or miss a turn in busy traffic and allow the driver to navigate more easily. Perhaps a downside, as with many new technologies, is the willingness or ability of the older generations to embrace and learn how to use the new device, hence reducing their effectiveness in navigation using the Navmap.