Specimen Paper Computing

1(a)	Computer systems are used in most supermarkets to run the stock control system.
(i)	Describe in detail why computer systems are useful in this context.	[5]
	stock levels are automatically adjusted when items are sold. re-orders of items with low stock levels can be automatically done by the computer system. special offers on certain items can be easily administered. statistical information can be produced - items with most sales etc. theft of goods can be detected because the stock level would not match the number of items on the shelf.	(make sure you have at least five different points)
(ii)	Describe two ways in which computing developments in the last two decades have favoured this type of application.	[2]
	more powerful computers mean faster speed of processing and larger storage capacities. hardware and software costs have decreased
(b)	Most stock control systems use databases.
(i)	One advantage of using a database rather than a traditional file system is that it reduces data duplication. Give two reasons why data duplication is undesirable.	[2]
	inconsistency of data may arise. ie two versions of the same data may not be identical. it is a waste of storage space.
(ii)	Database applications can be more secure than traditional file systems. Give two reasons why this is the case.	[2]
	different permissions may be granted to different users read-only access may be given to prevent accidental data corruption.

2.	A new light railway system is to use driverless trains. A computer system will control the movement of trains between stations and will include comprehensive safety systems. For instance, the trains will not move if any door is open and will stop if an obstruction is sensed on the line ahead.
(i)	State two inputs which will be required to the control system of the train.	[1]
	input from sensor on the doors which indicates whether the doors are open. input from a sensor which detects whether an obstruction is on the line
(ii)	Describe two outputs which will be required from the control system of the train.	[2]
	output signal to the brakes to operate output signals to the computer system indicating position and speed of the train.

3.	Explain the terms:
(i)	serial file organisation;
	Records are stored in the file in the order in which they arise. Eg sales transactions for a mail order catalogue company.
(i)	sequential file organisation;
	Records are sorted in order of a key field. Eg sales transactions may be sorted in order of item code.
(b)	Explain the difference between fixed length and variable length records. State one advantage of each type of record.
	Fixed length - each field has the same length ie number of bytes of storage. Advantage - greater speed of processing eg finding a record. Variable length - each field is separated from the next by a terminator. Advantage - saves storage space

4(a)	Modern word processors contain many features. State the function of each of the following features. giving an example of its use in each case.
(i)	thesaurus	[2]
	gives alternative words with the same meaning Eg good gives capable,worthy, excellent,...
(ii)	header/footer	[2]
	text which can be placed at the top (header) or at the bottom (footer) of every page of a document. Eg : Title as a header; Page numbers as a footer
(b)	A criticism of word processing systems is that they often result in paper being wasted. Explain why this may happen.	[1]
	Documents may be printed, and then edited and re-printed many times.
(c)	A spreadsheet is used to calculate the wages of the employees in a small company.
(i)	Describe two features of a spreadsheet which make it useful in this application.	[2]
	formulae may be used to perform calculations graphs and statistical information may be provided.
(ii)	Most spreadsheet packages contain a macro feature. Explain the term macro, giving an example from the wages application.	[2]
	a single instruction which replaces a number of pre-defined instructions. Eg : a macro could be defined for setting the colour, font and alignment of a single cell.
(d)	Apart from job losses which may result from the use of word processing and spreadsheet facilities, state two areas of employment which have been considerably affected by the widespread use of these facilities, and explain how each has been affected.	[2]
	the nature of jobs has changed - less boring, repetitive tasks for secretaries - eg no need to type multiple copies of the same document. management would find spreadsheets useful for budgeting without the need for repetitive and complex calculations.

5.(a) (i)	Describe two important features of an operating system in a personal computer.	[2]
	controls input and output from peripherals. allocates memory to applications.
(ii)	Describe two additional features which the operating system of a mainframe computer might include, which would not normally be found on a personal computer.	[2]
	control of a multi-programming environment administration of job priorities
(b)	Explain the term on-line processing.
	the user controls the computer which is processing the job.
(c)	The phrase real-time processing can apply to two quite different computing environments. An example of the first environment is a real-time airline booking system. An example of the second environment is a real-time control system used to fly the aircraft. Explain the term real-time processing, making clear the difference between these two environments.	[2]
	data is input and processed so fast that the results can affect the source of the data. a real-time control system needs very fast response to processed data a real-time booking system processes transactions in the order in which it receives them but the response time is not so critical.
(d)	Give a detailed explanation of the term handshaking when used in connection with computer input or output devices. Give an example of handshaking as applied to the use of a printer.	[5]
	An exchange of signals between a computer and a peripheral device ...to find out if it is ready for transmitting or receiving data. A computer sends a signal to a printer to find out if it is ready to receive data, the printer responds with a signal of 'Ready or 'Not ready' if a 'Ready' signal is received by the computer, then data is sent.

6.(a)	Two computer workers, Matthew and Vicky, are discussing data security. "I always keep really valuable data on the hard disc of my personal computer," says Matthew. "I wouldn't keep it on a floppy disc." "I don't agree at all," replies Vicky. "I only ever keep valuable data on a floppy disc - I certainly wouldn't keep it on a hard disc." Describe how each of these points of view can be justified:
(i)	Matthew's point of view;	[1]
	floppy discs are more likely to be damaged by dust and become unusable - hard discs are sealed to protect them.
(ii)	Vicky's point of view	[1]
	the floppy disc can be removed and locked away in a safe place. You can also operate a write-protect tab.
	During this conversation, Rhiannon joins the other two, saying "Whichever you choose, it's always sensible to keep a paper back-up."
(iii)	Justify Rhiannon's viewpoint.	[1]
	Paper cannot become unusable because of hardware crashes or power cuts etc.
(b)	Optical storage devices which can be written to (usually known as writable CD-ROM drives) are increasingly available for storing valuable data. State one potential advantage and one potential disadvantage of this method compared with other methods named above.	[2]
	Advantage : unlikely to be damaged and it can be stored in a secure place. Disadvantage : the equipment and the CDs are quite expensive.

7(a)	Describe two advantages of an arrangement in which computers are networked, compared with standalone computers.	[2]
	hardware can be shared eg a printer data can be shared. All users on a network can access a database stored on a file server.
(b)	Describe one possible disadvantage of networking computers.	[1]
	there is a danger of hackers accessing sensitive data.
(c)(i)	Draw two diagrams which indicate the difference between a star network and a token ring network.	[1]

(ii)	Describe the operation of a star network.	[1]
	Each workstation is connected directly to the file server.
(d)	Describe the operation of a token ring network.	[3]
	Each workstation is linked to the next one tokens are sent around the ring network data packets are attached to these tokens containing the address of the receiving workstation, which collects it as it passes.
(d)	State the difference between a WAN (wide area network) and a LAN (local area network)	[1]
	WAN - computers connecte by teplephone and may be widely dispersed. LAN - computers on one site are connected directly with cable.
(e)	Many networks have some type of security system to prevent inappropriate access. Passwords are often used as a security measure to try to prevent unauthorised access. Describe three ways in which a password system can be made as secure as possible.	[3]
	passwords need to be changed at regular intervals passwords should not be too short - a minimum length should be specified passwords should not be obvious eg names, dates of birth, pet names etc

8(a)	State the meaning of the following two terms:
(i)	the internet;	[1]
	a world-wide network of connected smaller networks.
(ii)	an intranet.	[1]
	has the facilities of the internet but is based within one site on a LAN
	In the following part-question, additional credit will be gained if your answer demonstrates skill in written communication.
(b)	The internet can also be used to help people taking college courses. Course notes and examples are made available via the internet and students can communicate with their tutors via the internet. In addition to taking part in "distance learning", the students are able to use the internet for leisure and entertainmnt. Describe possible benefits and drawbacks of this distance learning arrangement ( to both students and staff) compared with a conventional course involving student attendance at the college. Also discuss the concern that many people have over the leisure use of the internet by young people.	[8]
	Staff and students will need to spend less time travelling. This is particularly important in a rural area, where they may live far from the college. There are educational advantages too, for instance, students may engage in on-screen discussion with other students and with staff. Course materials (including additional work for able students or remedial work for less able students) may be published electronically, thus saving paper. However the reduced face-to-face contact with both staff and students may hamper student progress. Many people are very concerned over easy access of young (and older) people to pornography, or material related to illegal drugs or other criminal information. There is also a concern about time-wasting, and that some people may suffer socially (and possibly physically) from spending too long in front of a computer screen. One of the major problems is that it is very difficult for governments to control access to the internet.