7.3.4 Physical vapour deposition (PVD), sputtering An ion hitting a metal surface after acceleration through more than 100 V will not stick or bounce off but will burrow into the surface, splashing atoms outwards. This is known as sputtering and provides a versatile alternative to thermal evaporation for metal-vapour deposition: more controllable, with adjustable uniformity, able to cope with alloys and high-melting-point metals and suitable for production-line automation. Given these advantages, it is also worth the effort to heat the
7.3.3 Plasmas More control can be achieved in vapour deposition if a plasma is generated. A plasma is simply a gas where a proportion of the molecules have been ionised. The ions remain in an uneasy equilibrium with the electrons they have released, prevented from recombining only because the electrons are hot and fast-moving, and so are difficult to trap. Plasmas are widely used in materials processing, with pressure ranging from 10−3 mbar to 1 mbar and typically up to 1% of the molecul
Introduction Pictures speak louder than words. But how can you use diagrams to help you? This unit looks at how diagrams can be used to represent information and ideas about complex situations. You will learn how to read, draw and present diagrams to help illustrate how ideas or processes are connected.
This unit is from our archive and is an adapted extract from Systems thinking and practice: diagramming (T552) which is no longer taught by The Open University. If you want to study formally with us
Learning outcomes After studying this unit you should be able to: describe the operation and mechanisms of the hydrological cycle; list and describe the major physical, chemical and biological characteristics of clean fresh water, and explain their effects on aquatic organisms; explain the mode by which potable water is produced through the processes of screening, microstraining, aeration, coagulation and flocculation, sedimentation, flotation, filtration and disinf
4.4 Unravelling sentences In the following passage, mark as many subjects, verbs and objects as you can. James was to drive them. The first day we travelled thirty-two m 2.9 Painterly techniques A sensuous use of colour subverted the neoclassical aesthetic, in which moral and intellectual messages – or, at the very least, a concept of ‘noble form’ – were intended to dominate. In the case of Delacroix, this attention to the effects of colour is heightened by a concern with the textural qualities of paint. In order to produce a matt but bright surface, he applied thin layers of oil glaze to an initial lay-in of distemper (see ten-Doesschate Chu, 2001, p.102). It is thoug Acknowledgements Prepared for the Course Team by Simon Buckingham Shum Except for third party materials and otherwise stated (see terms and conditions), this content is made available under a Creative Commons Attribution-NonCommercial-ShareAlike 2.0 Licence Tables 3.1 and 4.16.1 Ontologies + the Web = the Semantic Web Tim Berners-Lee, the inventor of the World Wide Web, has defined a vision of the Web's evolution into the Semantic Web:
The Semantic Web is not a separate Web but an extension of the current one, in which information is given well-defined meaning, better enabling computers and people to work in cooperation. The first steps in weaving the Semantic Web into the structure of the existing Web are already under way. 4.13 Technologies and explicit knowledge Knowledge-based systems have the ability to analyse specific kinds of information in order to take action. Since we have earlier defined knowledge as arising out of the interpretation of information as mediated by representations, we can claim that in a limited sense such systems can ‘know’ things: they have a representation of part of the world, and they have some rules that allow them to analyse that representation, from which they can decide on a course of action. In that sense, they h 3.4.1 Integrating memory systems into the flow of work There has been a substantial amount of research interest over the last decade in group/organisational memory systems. For example, software researchers have investigated the possibility of capturing design rationale, the key reasoning that underpins design decisions (Moran and Carroll, 1996). However, time and again projects have failed. A given information codification scheme encourages particular ways of thinking about information and the problem at hand: typically, information must 3.3.1 Metaphors for organisational memory systems Section 2 argued for a model of knowledge deriving from the situated interpretation of abstract representations. There is an active process by which different interpretations may result from a given information source. This is in contrast to the popular notion that knowledge can be unproblematically encoded and digitally stored and accessed. Bannon and Kuutti (1996) argue that the term ‘organizational memory’ is widely used to mean a repository based on an implicit ‘memory as bin 1 Overview The unit begins by looking at how it can be difficult for a manager in the process of recruitment and selection to maintain objectivity. Drawing up clear criteria to use throughout recruitment and selection can help the process. It then addresses the difference between the person–job and person–organisation approaches to recruitment. Subsequent sections review the different tasks to be completed and the different methods which can be used by the manager in this important process. Learning outcomes After studying this unit you should be able to: explain the relationship between research on national cultures and the development of the culture perspective in business studies; describe some of the problems of working in, and doing business with, businesses in other countries; offer a definition of organisational culture; recognise the factors that constitute or influence the culture of a business. Acknowledgements Except for third party materials and otherwise stated (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: 4.2.1 Defining the problem It is vital that the problem is identified correctly. If the risk management system is working properly, the problem should not have hit you completely out of the blue, and you should already have some idea what it is about. But, although there is often a temptation to skip the definition phase and go straight to causes and solutions, it is important to be as clear as possible about the nature of the problem as seen from different perspectives, by answering questions such as those below. 2.2 Basic principles Whatever resource you choose to use to find information on the internet, many of the same principles apply. Each source that you use will probably look quite different from the one you tried before, but you'll notice that there are always features that are similar – a box to type your search terms in, for instance, or a clickable help button. Different resources refer to the same functions using different terminology, but the principles behind them are exactly the same. The trick is to chec 3.2 Utility theory Utility theory is based on this assumption of rationality and describes all decision outcomes (financial and otherwise) in terms of the utility (or value) placed on them by individuals. Within this framework, decisions can be understood in terms of rationally ordered levels of utility attached to different outcomes. Bazerman (2001, pp.3–4), for example, describes a formally rational decision process for arriving at a decision with the greatest expected utility in the following terms:< 7.1 Sharing the project As we have seen, the execution of a project may depend on the involvement and co-operation of several departments or functions within an organisation. If this is the case, then, for it to succeed, they must be prepared to share ownership of the project, be willing to work together to help the project achieve its objectives and be happy to release adequate resources when appropriate. The project manager and their team therefore have to create and maintain good relationships with all interested 5.6 The history of medicine: a Scottish perspective This unit looks at how historians seek to understand past diseases and epidemics. These had social, political and medical implications as they inevitably damaged the economic resources of a community. An example based in the Edinburgh Royal Infirmary is used to illustrate how changes in medical delivery affected the local population. In addition there is a description of the work of the eminent Scot William Cullen, professor of medicine at Edinburgh University (1752), who described the Acknowledgements Except for third party materials and otherwise stated (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 Child Poverty Action Group (CPAG) for permission to use the book which has been adapted for Op
Activity 10
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