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5.2 New Zealand's changing environment

In this study I want to explore some possible effects of this new trade on the environment of one of the countries involved. I've chosen New Zealand, partly because the developments we have just been discussing happened only a few decades after the first large-scale settlements of Europeans, and had a strong influence on the direction of its economy. Some background information will help to set the scene.

New Zealand consists of two mountainous islands with a total area similar to that
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4.5 Global climate change

I would like to turn now to the possible consequences of our use of energy for global climate change. Our pattern of energy use relies heavily on burning carbon-based fossil fuels, releasing carbon dioxide which spreads evenly around the globe and builds up slowly in the atmosphere. Carbon dioxide is a greenhouse gas, which means that it has the potential both to warm the atmosphere and to change our global climate. It is not the only greenhouse gas but is the most important of those e
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4.3 The UK experience: competing trends

But one striking example does not make an argument. To try to get a fuller and possibly fairer picture of energy use by domestic refrigerators I'd like also to look at the UK experience over the past few decades.

To start with it helps to have a feel for which parts of the UK economy use the most energy. The UK Department of Trade and Industry (DTI, 1998), identifies four main economic sectors: domestic (households), industry, services and transport.

In 2003 the domestic sector (h
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5 Conclusion

The issue of climate change draws attention to the power of human activity to transform the planet in its entirety, and it is brought into sharp focus by the predicament of low-lying islands like Tuvalu. As we have seen in this unit, the issue of rising sea level and other potential impacts of changing global climate also point to the transformations in the physical world that occur even without human influence. Oceanic islands provide a particularly cogent reminder that the living things wit
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4.1 Uniting the developing countries

Several attempts have been made to form a united front of developing countries to negotiate a better deal at the WTO. They have met with little success because there are substantial conflicts of interest between them, for example between agricultural importers and exporters, and between small countries and those larger developing countries that have been able individually to use the lure of opening their markets to get a better deal from developed countries. Conflicts of interest arise too be
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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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References

Alexander, G. (2002) eGaia: Growing a Peaceful, Sustainable Earth through Communications, Florida, Lighthouse Books.
Allinson, C.W. and Hayes, J. (1996) ‘The cognitive style index: a measure of intuition-analysis for or
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1.3 Activities

Activity 2A sets the scene by focusing on the ‘big picture’ where you will be asked to choose between four alternative visions of the future. This activity radically shifts the scale of investigation from the personal to the global. However, as with all systems, the emergent behaviour of societ
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1.1 Aim

This study unit introduces you to the proposition that our mental models change through learning, and
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6.3 Summary of Section 6

  • In trying to find solutions to the specific problem of the water-boiler, where the need was for a particular response to a certain temperature change, we have gone into the principles behind the three classes of temperature effect – gradual, accelerating and sudden. This has provided you with mathematical models that are of real use in putting definite numbers to the magnitudes of these effects in any designs that are proposed. The ability to do this is j
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5.4 Critical modelling

Critical phenomena are the simplest to model of the three classes of temperature-dependent changes we have been examining. We don't need a power series such as 1 + αT+ βT2+…, nor exponentials such as exp(−Ea/kT). Instead we can describe the behaviour with logical expressions like these:

if T < Tc, then property=subcritical value (or fu
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4.2 Energy distribution

Atoms without much thermal energy will not be doing very much. Consider fifty million million million (50 × 1018) silicon atoms, bonded into a single massive network; I've chosen silicon, but any elemental solid would do. It will be a speck just large enough to be seen without a microscope. You know that if it is heated it will expand, at some stage it will melt and then eventually it will vaporise – that is because thermal energy effectively ‘rattles it to bits’. Having the
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4.1 Characteristics of processes activated by thermal energy

This is a long section and needs to be studied carefully. Keep your eye on the overall goal of seeking useful thermal effects on which to base devices.

This section continues the discussion of heat at an atomic level. You will need this background to appreciate the characteristics of processes activated by thermal energy – for example, the softening of glass in a gas flame, the diffusion of atoms through solids, the electrical conductivity of ceramics, and many chemical reactions. Suc
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3.3 Thermal stresses

When the temperature of an object increases (say, by ΔT) it expands. According to the linear model of thermal expansion the length increase is described by

What if there is a temperature change, but some constraint prevents the proper thermal size changes? The constraint
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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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2.1 Defining ‘model’

The word ‘model’ has a range of colloquial and technical interpretations, so we need first to establish the way in which this unit uses the term. As a start, we might suggest that a model is a simplified representation of reality, but even that simple definition raises some quite significant philosophical questions. A profound question is ‘what is reality?’ and I will briefly mention the distinction between modern and postmodern views of this later as an aside. Without getting
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4.2 The use of systems analysis in public policy

The application of mathematical techniques to military operations was pioneered in Britain during the Second World War (see Box 7) and became known by a variety of names (Hoos, 1972, p. 42). At the end of the war, the United States Air Force sponsored the application of those techniques and methods to problems of US national security. Funds to investigate the effects of new weapons systems and for the exploration of defence policy issues were allocated to defence contractors. From one of thes
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Stage 7: Implement changes

Finally, the agreed changes are implemented.

Like the hard systems approach, soft systems methodology is not seen as a ‘one pass’ procedure, but as a learning process. Iteration is a feature of the methodology's application. Learning is achieved in both approaches by the use of models, although soft systems has subsequently been enhanced to include a specific analysis of the culture and politics of the problem situation, as shown in Author(s): The Open University

Stage 2: The situation analysed

The first step is to develop a picture (called in soft systems terminology a rich picture) that encapsulates all the elements that people think are involved in the problem. Once the rich picture has been drawn, the analyst will attempt to extract ‘issues’ and key tasks.

Issues are areas of contention within the problem situation. Key tasks are the essential jobs that must be undertaken within the problem situation.

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3.1 Introduction

The basic optical-fibre link consisted of the source (laser or LED), the fibre and the detector, as was shown in Figure 1. Improvements in these components can increase the data rate, but the system is still a point-to-point transmission link and all signal processing, such as routeing
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