2.4 Worlds in motion: the importance of flows

‘The sea had welled up suddenly through thousands of tiny holes in this atoll's bedrock of coral.’ Do you recall this passage in Lynas's (2003) account of his first days on Tuvalu in Reading 1A? For me, this gives an impression of the islands being quite literally porous, a solid ground that reveals itself, now and again, to be not so solid after all. Lynas offers this particularly striking example of the island's openness to the world around it as evidence of a growing vulnerability that
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2.1 Issues of responsibility

The aftermath of the 2004 Indian Ocean tsunami saw an unprecedented aid effort to assist the affected regions. In the early days after the disaster, pledges of financial assistance from overseas governments were often outstripped by the generosity of their own populaces. This was a case when ordinary people around the world saw and were moved by the tragic circumstances of others far away (Rose, 2006), and they responded with gifts of money and provisions, and even with offers of their own sk
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Learning outcomes

After studying this unit you should be able to:

  • identify the economic issues faced by developing countries in mutilateral trade negotiations;

  • describe these issues from a developing country perspective;

  • explain how the economic power of nations impinges upon the ability of states to negotiate settlements that are beneficial to them.


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2.2 The purpose of this activity

For these short video extracts we have chosen to focus on two main viewpoints. Try not to look beyond the outline of the debate, for we are not expecting you to come to a conclusion about who is right and who is wrong – the issues are far too intricate for that. All you need to do is to recognise what the issues are and to be able to identify what arguments each side puts forward in support of its case.

The key skill being developed is identifying the arguments used by various individ
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1.3 Activity 1

Activity 1

Before you read on, I would like you to dwell for just a moment on the significance of this shift from direct investment by Western firms to the establishment of subcontracting ties with overseas partners. Aside from outside
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1.1Aim

The aim of this section is to practise the use of diagramming techniques as part of a fundamental shift in interpreting issues – from an assembly of static objects to a network of dynamic relationships.


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2.6 Mathematical communication

When you looked at the title of this reading, did you experience unease? Most people shudder at the thought of dealing with anything mathematical, remembering the torturous lessons at school trying to grapple with calculus, statistics and logic. Yet most of us use mathematical com
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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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5.1 Sudden changes

The third category of thermal effects identified in Section 2 are those associated with sudden changes. Here are some technically important examples where things change suddenly at a particular temperature:

  • Pure water boils at 100 °C (at atmospheric pressure).<
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4.4 Summary of Section 4

  • Thermal energy is a random thing, so any group of particles possessing it will have a distribution of kinetic energies.

  • The fraction of particles with energy greater than an amount E1 is proportional to exp(−E1/kT).

  • Thermally activated rates follow Arrhenius's law and are characterised by an activation energy.

  • Diffusion in solids and electrical conduction i
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6.5 RSS

RSS (‘Really Simple Syndication’ or ‘Rich Site Summary’) newsfeeds supply headlines, links, and article summaries from various websites. By using RSS ‘feedreader’ software you can gather together a range of feeds and read them in one place: they come to you, rather than you having to go out and look for breaking news. The range of RSS feeds on offer is growing daily. There is probably a feed to cover all aspects of your life where you might need the latest information, and you may
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2.3.3 The matrix team

In a matrix team, staff report to different managers for different aspects of their work. Matrix structures are often, but not exclusively, found in projects. Staff will be responsible to the project manager for their work on the project while their functional line manager will be responsible for other aspects of their work such as appraisal, training and career development, and ‘routine’ tasks. This matrix project structure is represented in Figure 2.


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4.1 Understanding the polymerization process

Converting monomer to long chain polymer is the final step in the polymer manufacturing sequence. Polymerization is usually highly favourable in thermodynamic terms, mainly on energetic grounds because ordering molecules into linked chains is a process where the entropy is decreased. Heat is always given out during polymerization owing to the very favourable energetics of reaction, a point you may have noticed if you have ever made GRP parts for your car, for example!

Advances in cataly
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3.3 Petrochemical intermediates and monomers

About 80 per cent of all petrochemicals end up in polymers, the most important building blocks being ethylene, propylene, butadiene and benzene. The first three can be polymerized directly but an important slice of their production is used to create more complex monomers. Ethylene is the progenitor of most vinyl monomers (Figure 3
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Stage 4: Generation of routes to objectives (how could we get there?)

This stage explores the different ways of achieving the defined objectives. It is the most imaginative and free-thinking stage of the approach. The idea is initially to generate as many ideas as possible, then to whittle the list down to two or three ‘definite possibilities’ that can be carried further in the development stage.


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References

IEC 60793-2-10 (1992) International Standard 60793-2-10 Optical Fibres – Part 2-10: Product Specifications – Sectional specification for category A1 multimode fibres, International Electrotechnical Commission.
IEC 60793-2-50 (1992) International Standard 60793-2-10 Optical Fibres – Part 2-;50: Product Specifications – Sectional specification for category B single mode fibres, International Electr
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Appendix 1 Terminology

After studying this unit you should be able to explain the meaning of the following terms:

all-optical network

angle-polished convex connector

bandwidth-distance product

chirp

combiner

connector

continuous wave operation

dense wavelength division multiplexing

direct modulation directional coupler dispersion

dispersion compensation dispersion-shifted fibre electro-optic material excess loss external modulation extinction ratio four-wa
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3.2 Directional couplers

A simple yet valuable device is the directional coupler (Figure 19). A directional coupler can be constructed from two single-mode fibres by bringing them into close contact and heating so that the glass melts and the two fibres fuse. Light can then pass from one fibre to the ot
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2.4.2 Dispersion in single-mode fibre

Because there is only one mode in single-mode fibre, there is no multimode distortion but pulses are spread by dispersion.

Dispersion is the effect of different frequencies propagating at different speeds, and there are various mechanisms in optical fibre which mean that in general a fibre is dispersive. Given that dispersion takes place, a transmitted pulse will be spread because different frequency components in the pulse will take different lengths of time to propagate
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