1.1 Getting an overview This section starts with an article from a technical journal – the sort that is read by academics and professionals working in a related technical field. It sets the scene for some of the technologies and issues that you will be encountering later in this unit. We're not going to ask you to read the entire article, but we would like you to get an idea of the article's contents, the kind of points the author is making, and the range of issues that it throws up. With this aim in mind, w
Learning outcomes When you have completed your study of this unit, you should be able to: understand and use correctly terms introduced in this unit in relation to communication networks; understand general principles involved in data exchange between ICT devices; work with numbers expressed in scientific notation, and use the Windows calculator to perform calculations on these numbers.
Acknowledgements The content acknowledged below is Proprietary (see terms and conditions). This content is made available under a Creative Commons Attribution-NonCommercial-ShareAlike 2.0 Licence
Grateful acknowledgement is made to the following sources for permission to reproduce material in this unit:
Author(s):
2 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.
1 1 The incredible shrinking chip Two Scottish computer engineers with little or no physics knowledge set out to make a semiconductor transistor. This was 50 years ago, and their efforts gained them the Nobel Prize. The versatility of that transistor is now at the heart of the electronics industry. Millions of transistor switches are shrunk down into the microprocessors that are found in computers, mobile phones and almost everything else electrical. The first transistor took years to plan and make; today more are made
Introduction This unit focuses on the creation of a semiconductor transistor – a versatile tiny transistor that is now at the heart of the electronics industry. In the video clips, the history of the incredible shrinking chip, its Scottish connections and an explanation of the physics that make chips work are accompanied by a reconstruction of making a transistor using the crude techniques of yesteryear.
7.1 Introduction Earlier on I indicated that in order for a processor to perform a defined function it needs to be supplied with a list of instructions called a program. In this section I shall explore this idea a little further. Software can be split into two categories, application software and operating systems. Application software is the name given to programs which enable a computer to perform specific tasks. The program that processes the image in the digital camera is one example; a word
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
Introduction There is more to computers and processors than simply PCs. In fact computers are ubiquitous in everyday life. This unit challenges how we view computers through the examples of processors in kitchen scales and digital cameras, as well as a work of art that, at heart, is a computer. This unit is from our archive and is an adapted extract from Computers and processors (T224) which is no longer taught by The Open University. If you want to study formally with us, you may wish to explore ot
Acknowledgements The content acknowledged below is Proprietary (seeterms and conditions) and is used under licence. This content is made available under a Creative Commons Attribution-NonCommercial-ShareAlike 2.0 Licence All materials included in this unit are derived from content originated at the Open University.
Acknowledgements The content acknowledged below is Proprietary (see terms and conditions) and is used under licence. Grateful acknowledgement is made to the following sources for permission to reproduce material within this unit. Figure 6 NanoElectronics Japan Figure 30 The Cottingley Fairies © Science and Society Picture Library
Figures
Author(s):
6.2 Authority and the variety of information sources Technology has massively increased the number and variety of news sources that we have access to. We still have printed books, magazines and newspapers, while digital techniques have increased the number of broadcast radio and TV channels that we can get. On the Web we have access to online versions of many of these. This allows us access to media that previously would have been inaccessible. With traditional news sources such as these, we have some understanding of the authority that t
5.1 Transmission of electrical signals on wires In the discussions of newsgathering in the Taylor and Higgins papers, you saw the significance of the development of systems that allowed long-distance transmission of electronic signals. Initially transmission used metallic wires (remember Taylor's reference to the importance of the ‘lines infrastructure’ and his mention of the ‘wire picture’) and later wireless transmission (terrestrial and satellite microwave) became important. In this section I shall look at some aspects of the tr
2.6 New media
Taylor now describes the era when film was replaced with analogue electrical video. 2.4 Comparing early sources of news
Taylor compares the merits of radio and newsreels, as sources of news, with those of newspapers. 2.3 Newsgathering and newspapers
Taylor now discusses some early information and communication technologies and the extent to which they had an impact upon newspapers. Introduction This unit is from our archive and it is an adapted extract from Networked living: exploring information and communication technologies (T175) which is no longer in presentation. If you wish to study formally at The Open University, you may wish to explore the courses we offer in this curriculum area. This unit looks at the technologies used to acquire information about 6.9 Alternatives to the main success scenario If a use case incorporates a scenario that is significantly different from the main success scenario, you may decide to create a new subsidiary use case. There may even be a need to create more than one subsidiary, depending on what happens in different circumstances. For example, when making a reservation in a typical hotel the receptionist would first determine whether the guest was already known to the hotel (among other advantages, this would speed up the reservation process since re-ente 6.8 Sharing behaviour between use cases For each use case there may be more than one scenario. In the process of requirements elicitation and specification, you may find a certain amount of common behaviour in two or more of your use cases. You may even find that an existing component can provide part or all of that common or shared behaviour. Indeed, if you do find such an existing component, this is an example of reusing requirements which is discussed more fully in MRP. You can record the shared behaviour in 6.5 More about actors In the hotel example, you saw two actors in the use case diagram shown in Figure 3 (reproduced below). Why is the actor Guest associated with the use case for making a reservation but not associated with the use cases for checking in and out? The answer comes from an understanding of what happens when someone, a guest, arrives at a hotel. Hotels are service oriented. That is to say, they offer certain services to their guests with the intention of earning money for the business. A hote
From film to videotape
Radio and newsreels
Newspapers
