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6.3 What is the main requirement for regional government? Is it a shared identity?

If we compare the UK with other Western democracies such as Spain, Italy or Germany – all endowed with decentralised structures allowing various degrees of political autonomy for their regions – we discover that strong regional identity, as in Catalonia, the Veneto and Bavaria, is always a very important feature. However, some newly created regions such as La Rioja and Madrid in Spain also exercise devolved powers. What unites them is a common interest; the belief that regional government
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5.1 The UK model of devolution

In its programme of devolution, the Labour government had to decide whether to adopt a symmetric decentralisation model, which would confer an equal degree of devolution to the UK's constituent nations, or to implement an asymmetric decentralisation model, which would grant differing degrees of autonomy to Scotland, Wales and Northern Ireland. They opted for the second model in an attempt to respond to different claims about self-determination and to react to different degrees o
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1.2 Key ideas

  1. Labour market disadvantage can be manifested in a number of differences between the labour market experiences of different groups: differences of pay, of likelihood of unemployment, and differences due to occupational segregation.

  2. Labour market disadvantage and discrimination are not the same thing. Discrimination refers only to those differences between groups of workers that do not correspond to objective characteristics that affect the prod
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The database development life cycle
No idea how relational database systems are constructed? Did you know that they underpin the majority of the managed data storage in computer systems? This free course, The database development life cycle, has been designed to give you an overview of the developmental lifecycle for a database system, explaining the importance of data analysis and highlighting how database development differs from traditional software development.Author(s): Creator not set

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Except for third party materials and otherwise stated (see http://www.open.ac.uk/conditions terms and conditions), this content is made available under a http://creativecommons.org/licenses/by-nc-sa/2

Processes that can be applied to data

Having looked at some forms of data, we now turn our attention to processes that can be applied to data. Each process that we consider in this section will input data of a specified form, and will result in a corresponding value. For example, one process, which we will call ASC, takes a character as input, and has as its resulting value the integer giving the ASCII code of the input character (as listed in Author(s): The Open University

3.4 Representing data in applications

Suppose that you are designing software for some application. You will be working with a programming language that enables you to communicate instructions to a computer. In this programming language, certain forms of data will already be represented electronically. These will include common forms of data, such as numbers, characters and sequences. In any particular application, you are likely also to be concerned with forms of data that are peculiar to that application. Having identified some
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3.5.1 IPv4 Addresses

The allocation of addresses on the Internet is controlled by the Internet Assigned Numbers Authority (IANA), although authority is delegated to several local registries. IPv4 addresses may be interpreted in two ways. Initially, they were divided into distinct ranges of addresses called classes, but this proved to be inflexible and now a more flexible scheme, called classless addressing, dominates IPv4 internetworks. I shall describe both ways of interpreting IPv4 addresses because the limitat
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2.4 Examples of layer functions

There are several functions that can be performed at one or more of the OSI layers. Some of the more common ones are discussed below.

Connection control

For connection-oriented services, a connection must be established between peer entities. A connection has three phases: connection set-up, data transfer and connection clear. If the peer protocol supports connections, each protocol data unit type corresponds to a primitive type; for instance, a connection request primiti
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1.1 Abbreviations used within this unit

While reading this subject you may come across the following abbreviations.

AAL – ATM adaptation layer

API – application program interface

ARP – address resolution protocol

ATM – asynchronous transfer mode

B-ISDN – broadband ISDN

CLP – cell loss priority

DNS – domain name system

FTP – file transfer protocol

HTTP – hypertext transfer protocol


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5.5.5 Summary

In this section I've briefly considered the very contentious question of what digital representations mean, but this debate must be left to another course. I have also described some of the devices that take digital information back into the analogue world of sight and sound, presenting it in a form that is meaningful to human eyes and ears.


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2.2.1 Positive integers: denary numbers

The number system which we all use in everyday life is called the denary representation, or sometimes the decimal representation, of numbers. In this system, the ten digits 0 to 9 are used, either singly or in ordered groups. The important point for you to grasp is that when the digits are used in ordered groups, each digit is understood to have a weighting. For example, consider the denary number 549. Here 5 has the weighting of hundreds, 4 has the weighting of tens and
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8 Computers

In sections 8–14, I am going to start by considering a stand-alone computer, which is a computer that is not connected to a network. In this type of ICT system, the key processes are the manipulation and storage of data. I'll be introducing some details about the way that a computer manipulates and stores data. Then I'll be discussing the processes that are carried out by computers when they are linked.


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4.1.1 The transmitter

The transmitter receives a message from User 1 and manipulates it into data which can be sent into the network. The transmitter may also store or retrieve data relating to the message.

In the mobile phone system, the transmitter, which is User l's mobile phone, receives a message from User 1 in the form of sound. It manipulates the incoming sound into a data format suitable for sending into the mobile phone network. Even basic models of mobile phone handsets can store names and telephon
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2.3 How to use text to good effect

Two aspects of the use of text are:

  • How to ensure that your text is legible.

  • How to write text that suits the medium.

We consider the first of these in this section. We do not cover how to write English that is appropriate for your particular readers here. However, it is important to ensure that your text does not contain words or expressions that may be unclear to your readers. You must select text that is meaningful to
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7.4 Using flowcharts to describe a task (contd)

Now consider what happens when you are weighing, for example, flour on a set of scales. You slowly add more flour to the scalepan until you reach the desired weight. As you do this the display constantly changes, showing the weight increasing as you add more flour. To do this, the scales’ computer must repeatedly examine the input and update the display each time it does so. The flowcharts in figures Author(s): The Open University

6 A look to the future

So what will computers do for you next? Perhaps they will be the key to solving transport problems. Driverless cars, controlled by computers, are under development. If these ever come to fruition perhaps they could help to reduce the number of road traffic accidents by automatically reducing their speed when they come too close to another car. Or perhaps journeys could be made faster and less frustrating because cars will use communicating computers to analyse traffic density and move along t
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5.4 Conclusion

You have seen that although the three products you have looked at are very different types of computer, they all embody the same basic functionality and a version of Figure 3 can be drawn for each product to illustrate this.

One feature of the PC is the range of forms of secondary memory it can use, and also the vari
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5.3 Digital camera

The last computer I am going to look at is the embedded computer in a digital camera.

Figure 10 shows a picture of a digital camera. The screen of the camera is displaying a picture that has previously been stored in a memory card within the camera. This memory card is not the camera computer's main memory, nor is it the secondary memory used to hold the computer's program; it is a form of removable secondary memory where the computer stores the images taken. Next to the camera in Figur
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5.2 Electronic kitchen scales

A set of electronic kitchen scales is shown in Figure 7. Their basic operation is relatively simple. When they are switched on and, for example, a 500-gram object is placed in the scalepan, the display shows the digits 500 and the letter g.

3.1 Processor statistics

In Sections 3.1 and 3.2 you are going to find out a little more about one of the key components of a computer: the processor, which manipulates data according to a list of instructions called a program.

Here is a mini-quiz which explores some facts about processors.

Question 1


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