3.2 Systems concepts: system

The word ‘system’ is from the Greek word meaning a complex, organised whole. It has been used in this sense throughout history, and the Oxford English Dictionary records examples of usage dating from the early eighteenth century. Figure 24 shows a simplified diagram of a typical system. It indicates the boundary of the system,
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3.1 Introduction

As you would expect, since this unit deals with systems engineering, it embodies the principles and methods associated with a systems perspective. So it is important that you understand systems and the systems perspective at the beginning of the unit.

To have engineered a system successfully, all its features – the technology, control systems, people and related aspects of the physical environment – have to contribute to the achievement of its objectives. In other words, it h
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2.3 Summary and conclusions

This topic has addressed the question ‘What is modern engineering?’ The conclusion must be drawn that, until recently, engineers were content with fairly simplistic definitions of their profession, thinking that it consisted of little other than craft skills or practical experience grafted on to a knowledge of mathematics and appropriate natural sciences. It has been methodologically naive, and definitions of the processes of engineering either lack detail (Author(s): No creator set

2.2 A modern view

Modern attempts to define engineering recognise the importance of the resources identified by Sage, and that the subject can be divided into two components: engineering knowledge – the ‘know-what’, and engineering process – the ‘know-how’. Engineering knowledge is:

[…] the growing body of facts, experience and skills in science, engineering and technology disciplines; coupled to an unde
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2.1 The development of engineering

Engineering is one important component of systems engineering. In this topic I will examine the development of engineering before presenting a modern view of the subject. Section 3 will then pick up and discuss the idea of systems engineering.

William Shipley, a drawing master from Northampton, was instrumental in founding ‘the Society Instituted at London for the promotion of Arts, Manufactures and Commerce’ in 1754. This later became the Royal Society for the encouragement of
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1.9 Increasing complication, complexity and risk: summary

The three levels of change problem, simplicity, complication and complexity, can be associated with craft, engineering and systems engineering knowledge. The three categories of change problem represent different levels of uncertainty of what needs to be done and how to do it. The greater uncertainty brings increased risk. Although we tend to be risk averse we will take on greater risk if the returns are commensurate with doing so.

Human experience can be divided into three worlds. The
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1.8 Increasing complication, complexity and risk: are systems becoming more complex?

Figure 17 shows the evolution of two commonly encountered applications of systems – for personal transport and for the reproduction of recorded music. In both cases the degree of complexity of the systems application has increased over time. One of the main reasons for this is technology push. The importance of technology can be related to the stages of the product life cycle shown in Author(s): No creator set

1.7 Increasing complication, complexity and risk: a spectrum of systems intractability

Summarising the discussion in the previous two sections, Figure 12 shows what might be termed ‘a spectrum of systems intractability’. At one end of the scale are simple systems. These are easily understandable and their design and development (relatively) unproblematic. The way in which the various elements in the system fit and work together is clear. Outputs and behaviours are predictable. An example of a simple
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1.5 Increasing complication, complexity and risk: the underlying relationship

Figure 3 showed five commonly encountered problems of effecting different types of change. These are notionally located on a spectrum of change that ranges from no change at all, to complete revolution. The relationship suggested on the figure is that as the degree of change – represented by the different types of problem – increases so, too, do difficulty and risk. Each of the five problems of effecting change can be r
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1.4 Example 2: The Bridge of Sighs (and Wobbles)

The second example of a systems failure is the Millennium Bridge across the Thames linking the St Paul's area of the City of London on the north side of the river with a new cultural centre emerging in Southwark on the South Bank.

The bridge was to be solely for pedestrians, and was an idea first put forward by David Bell, who was at that time Editor of the influential Financial Times newspaper. The paper sponsored an international design competition which was won by a consortium
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1.3 Example 1 The Workcenter that didn't

Autodesk Inc. is the world's largest supplier of design and engineering software. It currently markets over thirty products but is most famous for its AutoCAD® two- and three-dimensional design and drafting software. The company is the market leader in this type of application, with over 4 million customers worldwide.

The Autodesk story began in 1982 with a group of programmers, centred on San Francisco, writing code for design software in their spare time. The group demonstrated a
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1.2 The Phoenix project

It is all too easy to dismiss problems like that being experienced with the tax credit system as being inherent in the design and implementation of computer-based systems. But they are not restricted to computer systems, as the example of the Phoenix project in Box 2 shows.

Box 2 Fly-away drones put robot air force off course


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1.1 Introduction: what is the problem?

In late June and early July 2005 a row erupted concerning the operation of a major flagship of government social policy, the tax credit system. Introduced in 2003, it was designed to help those on low incomes and whose social circumstances prevented them from working full-time (Citizens Advice Bureau, 2005). The article reprinted in Box 1 indicates the extent of the political unrest with a system that left families relying on food parcels, and that has been variously described as being ȁ
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Next steps
Visitors may gain an insight into the workings and material of the course. Visitors may experience for themselves how a few simple measurements can identify energy savings in their homes. Registered students can prepare on OpenLearn before the course website opens, in particular by starting their systematic monitoring of home energy usage.
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6.4 T152 monitor support
Visitors may gain an insight into the workings and material of the course. Visitors may experience for themselves how a few simple measurements can identify energy savings in their homes. Registered students can prepare on OpenLearn before the course website opens, in particular by starting their systematic monitoring of home energy usage.
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6.3 Using the monitor
Visitors may gain an insight into the workings and material of the course. Visitors may experience for themselves how a few simple measurements can identify energy savings in their homes. Registered students can prepare on OpenLearn before the course website opens, in particular by starting their systematic monitoring of home energy usage.
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6.2 Getting started
Visitors may gain an insight into the workings and material of the course. Visitors may experience for themselves how a few simple measurements can identify energy savings in their homes. Registered students can prepare on OpenLearn before the course website opens, in particular by starting their systematic monitoring of home energy usage.
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6.1 Introduction to the home monitor
Visitors may gain an insight into the workings and material of the course. Visitors may experience for themselves how a few simple measurements can identify energy savings in their homes. Registered students can prepare on OpenLearn before the course website opens, in particular by starting their systematic monitoring of home energy usage.
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5.4 Difficult appliances
Visitors may gain an insight into the workings and material of the course. Visitors may experience for themselves how a few simple measurements can identify energy savings in their homes. Registered students can prepare on OpenLearn before the course website opens, in particular by starting their systematic monitoring of home energy usage.
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5.3 Using the monitor
Visitors may gain an insight into the workings and material of the course. Visitors may experience for themselves how a few simple measurements can identify energy savings in their homes. Registered students can prepare on OpenLearn before the course website opens, in particular by starting their systematic monitoring of home energy usage.
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