HCI (More)

2010-04-21T11:29:00.003+01:00

Good Human Computer Interfaces (HCIs) are designed so they have features suitable for the intended user.

(a) Graphical User Interfaces (GUIs) are suitable for the non-expert user.

Give two features of GUIs which make them suitable for the non-expert user. [2]

(b) Name a different suitable HCI for each of the following:

(i) A computer programmer; [1]

(ii) A person with special needs. [1]

Answer
(a)
Any two of
• Online help / help buttons / screen assistants
• Online tutorials
• Favourite settings
• Intuitive / easy to learn
• Interesting flashing symbols / colour (if justified)
• Do not have to learn commands
• WIMP (only 1 mark)

(b)

(i) DOS / command driven / DCL (direct command language) / CLI (command line interface)

(ii) Special devices

e.g. Braille keyboards
Voice input / speech recognition
Touch sensitive devices
Concept keyboard
Virtual reality

HCI Questions

2010-04-21T10:21:00.000+01:00

HCI

Jan 09
Several types of Human Computer Interfaces (HCIs) are used with computer systems. Each type of HCI provides specific benefits to the user.

(a) Describe a sensible use and benefit of the following types of HCI.

You should describe a different use and benefit in parts (i) and (ii).

(i) A touch sensitive screeen. [2]

(ii) A biometric device. [2]

(b) Name an application which uses a voice interface and discuss any disadvantages associated with the use of voice interfaces. [3]

1 mark Description of use
In museums to allow children to gather information / in shops to enter info at POS
/ mobile phones to dial / display information

1 mark Benefit
Saves having to type, easier for disabled people to .., no need for mouse and keyboard,
quicker to enter information,

1 mark Description of use
e.g. retina scan / iris recognition to gain access to room, thumbprints to take out a library
book / registration systems / for security /instead of or as well as passports

1 mark Benefit
Individual / difficult to copy / better security(but cannot get in both parts)
Accuracy
Can lose smart cards

1 mark example and 2 marks for two problems
Or 2 marks for two examples and one mark for problem
Need to be clear that candidates are discussing input Speech recognition systems

e.g. Voice control in car navigation systems - not brand name
Security systems
Control systems
Telephone ordering system

Disadvantages
Have to train computer to recognise voice which takes a long time
Delays in getting commands recognised / rural accents / similar sounding words or commands /
background noise / security as people can hear password

Natural language interfaces
E.g. Giving instruction / asking question such as in expert systems.

Networking (Answers to questions)

2010-04-19T10:43:00.002+01:00

Jun 09
Both LAN’s and WAN’s are widely used in health care. Using suitable examples describe the impact these different types of networks are having upon the working practices in the Health Service.

Either six distinct points or 3 well discussed.
To get more than 4 marks both concepts of LAN and WAN must be discussed.
X-rays and scan results are now available almost instantaneously across a hospitals LAN from radiography to a consultant’s room. This allows quicker and more efficient diagnosis, patients can also be shown the images when they are in their own beds.

Expert systems such as NHS direct are now available over the web, which allows patients to access information without having to leave their own home and saves doctors from having to deal with minor ailments.

Doctors’ surgeries can now access blood test results from hospital pathology labs across the web, allowing faster and more up to date results, hence allowing more accurate diagnosis.

Internal communications across a hospital LAN or to consult with an expert in another country quickly via email.

Videoconferencing from doctor’s surgery to a skin specialist for remote diagnosis.

Patient record keeping systems allowing better internal transfer of information.

Sharing of resources e.g. in the US there are four high-voltage electron microscopes.

Doctors can send samples for analysis and then view the results via a video link.
Intranet for internal notices such as job vacancies, forms, documents.

Automatic stock control of supplies and medicines.

(6)

Jan 07
A school has installed a new local area network (LAN) to help with its school administration.

(a) Describe how the school staff could use the LAN to help with administration. [4]

(b) Discuss two health and safety issues which the school should consider when designing the LAN. [2]

(c) Explain how the school can prevent:

(i) accidental loss of data; [3]

(ii) deliberate destruction of data. [3]

1 mark for each example x 4
(Credit can be given for fuller descriptions 2 x 2 or 1 mark each for naming two examples and 1 mark for third with extra mark for fuller description of a third)
• School record keeping such as pupil data to give form lists / year list
• Registration systems such as OMR or use of wireless systems, allow attendance information to be accessed from many points
• Examination entries can be done via the intranet facilitating easier updating
• Standard letters can be kept on file e.g. parents' evening letters
• Internal messaging leading to better communications

Note – four general answers may be credited with one mark in total.
Any reasonable answer
1 mark for each example x 2
Only 1 mark if list
• Screen filters should be used to reduce radiation hazard
• Adjustable chairs must be provided to avoid back strain
• Take regular breaks to avoid eye strain
• Use of wrist rests to avoid RSI
• Rooms should have ergonomic lighting to reduce eye strain.
• There should be no trailing cables to avoid risk of accident.

Note – cause or solution acceptable
Any reasonable answer
Accidental loss
1 mark for each measure x 3 (Max 2 marks if a list and not discussed)
• Regular back-ups should be made of the data on the system using suitable backup storage. The main method used to back-up network data is the Grandfather-Father-Son method.
• Back-up files should be kept secure – ideally in locked, fireproof rooms or safes in a different location to the network.
• Archiving means copying or moving files somewhere for long-term storage.
• Some software and files can be protected by asking user to confirm action (are you sure?)
• Restrict files to 'read only'

Note – do not accept 'backup' on its own
1 mark for each measure x 3 Could have two from one area
Deliberate destruction
Area
Prevent access to data Hierarchy of passwords / access rights
Encryption

Prevent access to rooms Smart cards
Retina scans
Thumbprint scans
Physical lock
Prevent destruction by viruses Virus detection and eradication progs. Firewalls

Jun 07

An organisation has decided that its ICT system needs upgrading and a network installed.

(a) With reference to appropriate examples, other than sharing peripherals and email, describe three benefits that networking would give the organisation in dealing with its administration needs. [3]

(b) The organisation also realises that it needs an Intranet. Define the term Intranet and describe one advantage to the organisation of having an Intranet. [2]

(a) Information can be shared and collected from a central pool [1]
IT manager can monitor what work staff are doing from central point [1]
IT manager can install software from central point without going around
each machine. [1]

 Backups can be centrally done.
 The user can work at a multitude of points.
 User security policies can be centrally administered.
 Pop up messages with important information.
 Web conferencing without leaving the desk.
 Easier to collect data from a number of stations to be stored centrally.

(b) A closed private network only accessible by certain users. [1]

Allows staff to access privileged work from home. [1]
Allows users access to information which outsiders cannot have.
Allows additional security to information as stays inside the organisation.

Jun 06
A large supermarket company has many shops throughout the country. The company uses both a Local Area Network (LAN) and a Wide Area Network (WAN).

(a) Explain the difference between a LAN and a WAN. [2]

(b) Describe a suitable role for a LAN in the supermarket stock control system. [2]

(c) Describe a suitable role for a WAN in the supermarket stock control system. [2]

(d) Discuss, using specific examples, the advantages of using LANs and WANs:

(i) for the supermarket customer; [3]

(ii) for the supermarket manager. [3]

Use distinctly different examples in each case.

A
1 mark each
LAN network restricted to one building / site / shop
WAN network across towns / cities / linking all shops
1 mark LAN controlling POS systems
1 mark Linked into shop server collecting daily sales
/ looking up prices / querying in-store stock, (not
querying stock on its own).

1 mark - WAN ordering and distribution from warehouses
/ suppliers / querying stock in another
store/warehouse (not querying stock on its own).
1 mark - Receiving sales / stock reports from each shop
and ordering stock from distribution centres to be
sent to shop.

B
Any 3 of
(i) To the customer
* faster and more efficient checkout services
* itemised till receipts
* products more tailored to their needs
* fresher goods due to low stock levels held by
supermarkets
* special offers
* benefits to the supermarket passed on in the way of
lower prices or increased customer services
* various methods of payment
* chilled or frozen food kept at the correct temperature
* loyalty card / points
* on-line shopping
* price checking
* checking goods’ availability

D
Any 3 of
(ii) To the supermarket and its management
* efficient stock control, less chance of goods being out of
stock
* more efficient checkouts, less chance of errors by staff
* ability to use sales forecasts and 'profiles', leading to
more efficient use of shelf space
* little warehouse space required in each supermarket due
to distribution system
* ability to monitor the performance of checkout staff
* shelf pricing more cost effective than labels on products
* ability to use electronic funds transfer improves cash
flow
* effective management of chilled and frozen goods
* accessing management information from many points
* easily compare data with other stores
* communicate with other stores, e.g. about active
shoplifters
* headquarters sending company related information, e.g.
targets
* the setting up of a fake website could affect the
reputation of the company
Do not give credit for general advantages of LANs such as
sharing of resources, information and communication
without reference to the supermarket context.
Candidates should not be credited for straightforward
repetition of the same point in different parts of the
question.

E
Any 2 of
Advantages
reach wider audience / more shoppers
offer alternatives if goods customer wants is out of
stock
ability to use electronic funds transfer improves cash
flow
collect data on customers to target products and special
offers
need less staff
carry less stock on shelves / need less space / just in
time
Any reasonable answer
Any 2 of
Disadvantages
development / maintenance costs of website
competitors can view prices and marketing techniques
destruction of data / site due to viruses or hacking
increased training needs

Any reasonable answer

AS Revision Blog for AS level ICT

2010-04-19T08:00:00.000+01:00

This Blog will be used to post up work and resources used in AS Level revision.