1.3 Nick Ut's 1972 Vietnam war photograph

Figure 1 Huynh Cong (Nick) Ut, 1972.
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Acknowledgements

This free course is an adapted extract from the course DD203 Power, dissent, equality, which is currently out of presentation

This chapter is taken from Living Political Ideas (eds) Geoff Andrews and Micheal Saward published in association with Edinburgh University Press (2005) as part of a series of books which forms part of the course DD203 Power, Dissent, Equality: Understanding Contemporary Politics.

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5.4 Devolution in Northern Ireland: a particular case

Devolution in Northern Ireland has been an integral part of the post-1994 peace process, which aims to share power between the two divergent communities, the Unionist-Protestant majority and the Republican-Catholic minority. All-party talks, chaired by the former US Senator George Mitchell, followed the 1997 renewal of a paramilitary ceasefire. The decommissioning of arms by paramilitary groups was made a condition of the talks, but no specific date for its accomplishment was ever given. This
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Take your teaching online
In this free course, Take your teaching online, you will gain  knowledge fundamental to delivering effective teaching online. You will hear about the experiences of real educators, be introduced to cutting edge research, and understand the ideas and tools that shape how we teach and learn online. You will also learn useful methods that will guide you to test out these new ideas in your own practice. Author(s): Creator not set

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Objectives for Section 1

After studying this section you should be able to do the following.

  • Recognise the terminology: character; string; integer; sequence; element (of a sequence); variable; identifier (of a variable); state (of a variable).

  • Use and interpret the notational conventions:

    • single inverted commas to show a character;

    • double inverted commas to show a string (sequence of characters);
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4.11.2 Scanners (again)

In Subsection 4.2.5, scanners came up as devices that can convert text into digital form. They do this by making a digital image of the page and then passing this image to an OCR system to distinguish the various characters. However, they are more often used to take images such as photographs and printed
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4.11.1 Digital still cameras and camcorders

These devices are now widely and (fairly) cheaply available. There is no film. You point your camera, take your shot and get a compressed digital image that can be transferred straight onto a computer, where it can be edited or printed. Digital still cameras usually compress their images into JPEG format and store them on a tiny, removable memory card inside the camera; the latest digital camcorders can record in MPEG format, stored on a special tape. Both devices work by means of an electron
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4.2.3 Text capture devices

Practically, how can we take text across the boundary?

SAQ 8

What are the main devices for transforming text into digital form inside the computer?


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3.10 A final word – analogue and digital worlds

So there we have it. On the one hand is our world, an analogue world – a world of light and sound, of taste and touch. On the other side of the boundary is the computer's digital world – a bleak world of binary numbers.

Before I leave the topic, though, I should point out that some of the points I've made may be controversial.

For a start, it's not entirely clear whether the world we inhabit is fundamentally analogue. Quantum theory tells us, for instance, that quantiti
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3.3.2 Enhancing the perceptual system

Magnificently evolved though it is, our sensory system is nothing special. We do not see as well as birds; our hearing is feeble compared to that of bats and some forest-dwelling mammals. Our sense of smell can't compare with that of dogs or pigs. There are many things we don't detect at all – radio waves, for instance.

In one capacity, though, humans are supreme: we have learned to enhance our perceptual systems with instruments. For example, the human eye has only a limited p
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3.1 Ghosts of departed quantities

They are neither finite quantities, or quantities infinitely small, nor yet nothing. May we not call them the ghosts of departed quantities?

(Bishop G. Berkeley, The Analyst)

This section follows up the ideas presented in and aims to:

  • define the terms analogue, discrete and digital;

  • look briefly at the human perceptual system, which e
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2.5: Crossing the boundary

So computers are used to acquire, store and present, exchange, and manipulate interesting characteristics of the world. But this raises a serious problem: the world we inhabit and know so well and the world inside the computer are very different in kind. We live in an analogue world. The world of the computer is digital. The exact meaning of these terms may not be very clear to you at the moment. I will define them both in the next section. For the moment, the only point
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Keep on learning

Study another free course

There are more than 800 courses on OpenLearn for you to
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8.4 The OR operation

The OR operation (occasionally called the inclusive-OR operation to distinguish it more clearly from the exclusive-OR operation which I shall be introducing shortly) combines binary words bit by bit according to the rules:

  • 0 OR 0 = 0

  • 0 OR 1 = 1

  • 1 OR 0 = 1

  • 1 OR 1 = 1

In other words, the result is 1 when either bit is 1 or when both bits are 1; alternativel
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6.2 Working with bits

You may have met the term bit, perhaps in connection with computers. The term 'bit' is also important in communication systems. It is an abbreviation for 'binary digit'. A binary digit can have just one of two values: it can be either 1 or 0. Pulses can be represented by 1s and 0s, that is, as bits, and so it is convenient to think of streams of 1s and 0s being conveyed along the communications link.

The rate at which the 1s and 0s are conveyed is known as the data rate or
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6.1 Networks

Next I'll be looking more closely at the 'network' block in Figure 8, and in particular at the links that must be present before communication can take place. I'll introduce you to just a few of the forms that these links can take; links may be physical ones, such as cables, or they may be wireless, such as radio links. I'll also d
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2 Conclusion

The versatile tiny transistor is now at the heart of the electronics industry. In the video clips you have seen the history of the incredible shrinking chip, its Scottish connections, and an explanation of the physics that make chips work as well as a reconstruction of making a transistor using the crude techniques of yesteryear.


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Conclusion

This free course provided an introduction to studying Computing & IT. It took you through a series of exercises designed to develop your approach to study and learning at a distance, and helped to improve your confidence as an independent learner.


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6.2.11 Dynamic pricing

The dynamic pricing model is one which has a number of different instantiations. Basically, such models treat the price of a product or service (primarily a product) as variable and open to negotiation.

The name-your-price instantiation of this model is where the customer of a site offers the price that he or she thinks is reasonable for a product or service. The administrator of the website will pass on this bid to the provider of the product or service who will decide whether t
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