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Figure

Figure 2.1: Ashley Jonathan Clements courtesy Flickr Photo Sharing and Image Source/Rex Featu
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3.2 (2B): Developing a relational model of the Powerdown Show programme

In this activity you will be challenged to reinterpret the following programme extracted from the Powerdown Show DVD: Energy Descent Pathways. The reason this programme was selected, from the many audio-visual programmes currently available online that tackle environmental and social issues, was because it presents an "ecotopian" approach to tackling the converging social, economic and environmental crises. Your challen
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3.1 (2A): Exploring the global implications of different mindsets

In this activity the aim is to investigate the implications of different mindsets with regards to the future unfolding of events on a global scale.

Activity

So far, you have focused your attention on exploring your personal cognitive
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2.5 Visual communication

As discussed in Reading 2.4, written text has major limitations in representing relationships between things when they do not follow the linear structure of the text. Relationships can be extremely complex, even circular, as you will see in this block. In particular, the linear sequence of text is not able to clearly show context, elements, structure, processes and functions of
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2.1 Learning and culture

As discussed in Reading 1.6, the behaviour of all living organisms that determines their resource use is mostly controlled by a set of models encoded in their genetic material. Most significant changes in the behaviour of a particular species of organism are usually a result of genetic evolution.
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5.2 What's in a phase?

In an engineering and scientific context, a phase is an arrangement of atoms that is identifiable through its recurrence – the same pattern is found time and again. For instance, the compound of hydrogen and oxygen that we call water turns up all over the place in the same form as a runny, colourless liquid; this is a specific phase of the compound H2O. In water, the atoms apparently organise themselves according to what they are and the ambient conditions of temperature a
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4.2.3 The significance of the distribution of energies

Near room temperature (300 K), the average bundle of thermal energy associated with a particle is 0.026 eV (look back at Box 2 Temperature and energy). This is not going to do much damage to something stuck together with bonds that have an energy of a few eV – just as the average wage earne
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4.2.2 The significance of the average energy

The average thermal energy of the atoms in a solid indicates how much they are ‘rattling’ or vibrating around their mean positions. Since the atoms are close together, virtually touching, and because atoms are almost incompressible, they cannot get much closer. But they can get further apart. So, since thermal energy is manifested in the vibrations of the atoms, bigger vibrations mean that the atoms must spend more time further apart. On average then, there is a tendency for a solid to ex
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1 Temperature – problem or solution?

‘Have you taken the temperature effects into account?’ (Figure 1) is nearly always a valid question in any discussion about a proposed engineering solution. Everything has a temperature, and everything behaves differently at different temperatures. It therefore deserves its own special plac
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5.7 Bibliographic software

If you are considering taking your studies further you might like to consider using bibliographic software. Bibliographic software can be used to sort references, annotate them, manage quotations or create reading lists.

There are several software packages on the market. Some are listed below.

3.9 News sources

Many news sources are now available online. Searching an online version of a newspaper is easier, quicker and more effective than searching through printed indexes, microfilm or actual newspapers.

EurekAlert!A global gateway dealing with news and links to information in the fields of
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3.3.1 Ethylene, propylene and butadiene

Nowadays ethylene is the most important building block for the chemical industry, particularly as a monomer in its own right, as a co-monomer with other vinyls, and as a source of vinyl monomers. It is the prime source for ethylene oxide, which is another major source of polymers, glycols and ethers. They can also be used to build up more complex C4 molecules and aromatics.

Some of the ways in which the ethylene molecule is modified to create other chemicals and polymers are
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2.6.2 Splicing

The usual technique for splicing in the field is electric arc fusion splicing. This involves aligning the two fibre ends and then fusing them with an electric arc.

Figure 17
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3.3 Magnetic tape recorders

Experiments showed that the use of paper tape coated with iron oxide particles significantly improved the signal-to-noise ratio and enabled a lower tape speed to be used. A plastic-based version of this magnetic tape, developed by the German company BASF, led to the development of a commercial tape recorder with audio characteristics that could nearly match those of the gramophone record, but not at an economical price. Secret work on tape recorders was undertaken by the Germans throug
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2.1 The importance of sine waves

For much of the rest of this unit we shall be concerned with the properties of a type of sound wave that when represented as a graph has a characteristic shape known as a sine wave. Figure 1 shows you what a sine-wave graph looks like. For the moment you need not be concerned with what this grap
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5.5 Multiple-cause diagrams

Multiple-cause diagrams are another way of using interconnectedness to structure a complex situation. In this case, the interconnectedness is that of causation. Multiple-cause diagrams represent both sufficient and contributory cause, without making a distinction between them. Drawing multiple-cause diagrams allows for the identification of systems of causation. Such a system can be pictured as an interconnected group of events or effects; the effect is of a system that behaves
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9.4 Influence diagrams

I want to return to the definition of a system I used earlier: an assembly of components interconnected as if they had a purpose. In the last section, I used purpose as a way of structuring the complexity of the case study. In this section, and the sections that follow, I want to turn to the idea of interconnectedness as another way of structuring the complexity. In the case of influence diagrams, I search for interconnection in the form of influence to hold together a structure
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