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4.5 M is for Method

Method is about the way in which a piece of information is produced. This is quite a complex area as different types of information are produced in different ways. These are a few suggestions to look out for:

Opinions – A lot of information is based on the opinion of individuals. They may or not be experts in their field (see P for Provenance) but the key message is to be clear that it is just an opinion and must be valued as such.

Research – You don’t have t
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4.3 R is for Relevance

Relevance is an important factor to consider when you are evaluating information. It isn’t so much a property of the information itself but of the relationship it has with your question or your ‘information need’. For example, if you are writing an essay about robotics a book or website about green energy would probably not be relevant. So there are a number of ways in which a piece of information may not be relevant to your query:

  • geographical
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4.2 P is for Presentation

By presentation, we mean, the way in which the information is communicated. You might want to ask yourself:

  • Is the language clear and easy to understand?

  • Is the information clearly laid out so that it is easy to read?

  • Are the fonts large enough and clear?

  • Are the colours effective? (e.g. white or yellow on black can be difficult to read)

  • If there are graphics or photos, do they help
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Introduction

The internet provides a world of information, but how do you find what you are looking for? This unit will help you discover the meaning of information quality and teach you how to evaluate the material you come across in your study of technology. You will learn how to plan your searches effectively and be able to experiment with some of the key resources in this area.

This unit is an adapted extract from the Open University course Author(s): The Open University

2.3.4 The contract team

The contract team is brought in from outside in order to do the project work. Here, the responsibility to deliver the project rests very firmly with the project manager. The client will find such a team harder to control directly. On the other hand, it is the client who will judge the success of the project, so the project manager has to keep an eye constantly on the physical outcomes of the project. A variant of this is the so-called ‘outsourced supply team’, which simply means that the
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5.6.3 Conformation and crystallinity

If there are key connections between the chain configuration and crystallisation, you might also expect some more subtle effects from rotation about chain bonds. After all, polymer chains must be able to twist into the regular conformation demanded for crystal structures (Figure 57(a)). And what influence will rotation have on
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4.3.4 Ionic polymerization

Free radicals are indiscriminate in the compounds they attack, and their non-selective nature in polymerization reactions leads to problems such as chain branching and transfer which affect the structure of the polymer produced. Anionic polymerization overcomes many of these problems.

A typical commercial (but also see Box 8
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2.3.1 Structural isomerism

In the saturated hydrocarbons, whose structural formulae are shown in Figure 16, it is not possible to form distinct isomers with just three or less carbon atoms linked together. There is only one way in which one carbon and four hydrogen atoms can be linked together, the single compound being methane, CH4. A simila
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6 Summary

This unit has covered the background to systems engineering. It began by addressing the question ‘Why is systems engineering important?’ Two reasons were discussed:

  • projects go wrong, and the increasing incorporation of software means that they go wrong more often now than in the past

  • complication, complexity and risk are all increasing and need to be managed.

In the second section I examined the development of en
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5.2 The aims and principles of system engineering

The aims of systems engineering can be divided into those to do with its outputs and those associated with the process itself. As far as its outputs are concerned, systems engineering aims to ensure that:

  • the requirements of all the stakeholders are taken into account in engineering the system

  • the system, as engineered and realised, meets the requirements of stakeholders

  • the system, while meeting the req
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5.1 Introduction: the general framework

The general framework of systems engineering adopted in the course consists of: a hierarchy of elements; aims associated within its outputs and process; a set of principles; a division into technical and managerial components of the process.

The lexicon of system engineering used in the course contains the hierarchy of elements:

  • strategy: meaning the accumulated decisions concerning the areas in which an organisation operates and its lon
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Stage 2: Analysis of the existing situation (where are we now?)

Having defined and agreed on the problem, it is necessary to decide on the system in which you consider it plays a part. In practice the two stages are closely linked and the analysis of the existing system nearly always means a redefinition or refinement of the problem or opportunity. Identifying and defining the problem and the system or systems that relate to it are critical for the success of subsequent analysis.


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3.4 Systems concepts: structure

As suggested earlier, the structure of a system is its functional or physical arrangement; the term that is often used in systems engineering is ‘architecture’. The architecture of a system can be deconstructed to reveal its constituent elements. I suggested in Section 1 that an existing knowledge base has an important bearing on the way in which a change problem is perceived. The way that this is conceived by one armaments system integrator is illustrated in
Author(s): The Open University

4.5.2 10 Gigabit Ethernet

The standard for 10 Gigabit Ethernet (IEEE 802.3ae, lOGbE) was approved in July 2002. The main use of lOGbE, initially at least, is for backbone networks which interconnect 10, 100 or 1000 Mbit/s Ethernet hubs. These hubs might be widely separated geographically, so the standard includes physical layer specifications specifically for WAN (wide area network) applications as well as LAN applications. The WAN specification is for operation at slightly under 10 Gbit/s, 9.95328 Gbit/s, so as to be
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2.4.1 Multimode distortion

With multimode fibre, the main cause of pulses spreading is the multiple paths that signals can traverse as they travel along the fibre. This phenomenon of multimode distortion is illustrated in Figure 5.


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6.1 Articulating your appreciation of complexity

I have organized the material in this section so that you can follow the activity route shown in Figure 6.

This section is primarily concerned with what can be understood by the term complexity, and how to compare it with the ideas of difficulty and mess. To do this, you are firs
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8.4 Stopping the etch

Just as important as being able to remove material is being able to stop doing so once the intended etch depth has been reached. Success or failure in this aspect of etching determines whether or not any of the benefits of parallel processing of thousands of devices will be obtained. Uniformity of result from device to device, and repeatability from wafer to wafer, are crucial to the economic viability of the whole exercise.

There are three broad categories of approach to this problem:<
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8.3.2 Sputter etching: argon ion etching of gold

One commercial process for cutting inkjet printer nozzles uses sandblasting. Not surprisingly, the surface finish is rather poor and there are issues with particles contaminating the devices. However, it is a physical process very like this that we need if we are to achieve a vertical etch profile.

The key is directed bombardment by highly energetic particles. When processing on the microscale, these particles are not sand grains but ions accelerated towards the surface by an electric f
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7.3 Depositing metals and alloys

Metal layers are used extensively in device fabrication: to carry current for both power and signals, to apply the voltages that control transistors and generate forces for MEMS, as mirrors and optical coatings, and in magnetic devices for recording media. Different applications might require a continuous film, a long track, multiple thin layers or a plug filling a ‘via hole’ through to a buried layer. The electrical properties resulting from micro structure and composition must be contro
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2.3 The fabrication process for a MEMS Pirani sensor

This section is fairly long, but is best read in one go. If you run out of time, reschedule your study to allow you to start again from here.

Thin layers of material are added to the surface by a variety of means, depending on the material to be deposited, and what is already on the wafer.

The sensor starts off, as so many microsensors do, with a silicon wafer, shown in cross section in Author(s): The Open University

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