Database lectures Part 4
Database lectures Part 4 - Kenneth Thomas Keywords:UNSPECIFIED
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01.12.2012 – Langsam gesprochene Nachrichten
Trainiere dein Hörverstehen mit den Nachrichten der Deutschen Welle von Samstag – als Text und als verständlich gesprochene Audio-Datei. *** Die US-Ratingagentur Moody's hat den europäischen Rettungsschirmen ihre Spitzen-Bonität entzogen. Sowohl die Bewertung des permanenten Euro-Rettungsschirms ESM als auch die des provisorischen Hilfsfonds EFSF seien um eine Stufe gesenkt worden, teilte Moody's in Frankfurt am Main mit. Der Ausblick für beide Rettungsschirme bleibt negativ. Grund fü
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How can content teachers use literature to promote social justice and social action?
Interview with Deborah MacPhee (dmacphe@IllinoisState.edu), Curriculum & Instruction Department, about how to use literature focused on characters with disabilities to promote awareness and social action. MacPhee, D., & Lintner, T. (2012) From social studies to social action for a disability inclusive world. Social Studies Research & Practice, 7(2), 1-19.
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Sea-based attack drone readied for first carrier trials
Nov. 29 - The US Navy's first sea-based, unmanned attack aircraft is being prepared for its maiden test flight from an aircraft carrier. The Northrop Grumman X-47 B arrived for duty aboard the USS Harry Truman on Monday (November 26) with the Navy expected to begin the first ever sea tests of a pilotless drone next month. Rob Muir has more.
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5.2 Summary of Section 5

  1. The structural formulae of organic molecules can be divided into the carbon-hydrogen framework or skeleton, and the functional group(s). In the first approximation, the functional groups are the sites where reaction occurs, the framework remaining unreactive.

  2. This approximation works best when the framework consists of saturated carbon atoms.

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Learning outcomes

After studying this unit you should be able to:

  • create simple models, given a clear statement of the problem;

  • write down the simplifying assumptions that underpin a model;

  • identify the key variables and the parameters of a model;

  • apply the input–output principle to obtain a mathematical model, where appropriate;

  • obtain mathematical relationships between variables, based on or linking back to the simplifying assumption
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5.1 Arithmetic with real numbers

At the end of Section 1, we discussed the decimals and asked whether it is possible to add and multiply these numbers to obtain another real number. We now explain how this can be done using the Least Upper Bound Property of Author(s): The Open University

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Learning outcomes

After studying this unit you should:

  • be able to solve homogeneous second-order equations;

  • know a general method for constructing solutions to inhomogeneous linear constant-coefficient second-order equations;

  • know about initial and boundary conditions to obtain particular values of constants in the general solution of second-order differential equations.


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1 Modelling with Fourier series

The main teaching text of this unit is provided in the workbook below. The answers to the exercises that you'll find throughout the workbook are given in the answer book. You can access it by clicking on the link under the workbook.

Click 'View document' to open the workbook (PDF, 0.6 MB).

1.3 Designing alternative programmes and curricula

Assuming that both the content of mathematics and the processes need to be included in programmes and curricula, the problem becomes one of how a suitable curriculum can be structured. One possibility is to construct a very specific curriculum with clearly defined objectives for both content and processes separately, and possibly with suggested learning activities. However, content and process are two complementary ways of viewing the subject.

An alternative is to see the curriculum in
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1.5 ‘Radiative forcing’ as an agent of climate change

Since its first major report in 1990, the IPCC has used the concept of ‘radiative forcing’ as a simple measure of the importance of a potential climate change mechanism. The basic idea is straightforward. Any factor that disturbs the radiation balance at the top of the atmosphere has the potential to ‘force’ the global climate to change: it will either warm up or cool down until a balance is restored. The perturbation to the energy balance of the whole Earth-atmosphere system i
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Introduction

This unit explores different understandings of nature and environment and the significance these may have for developing responsibility. The problems of connecting human and non-human nature are presented here as being a challenge peculiar to the concerns of environmental responsibility. They provide the impetus for exploring the idea of ‘conversation’ as a metaphor for what matters in environmental responsibility. Using a reading by Stephen Talbott as a foundation, the conversation me
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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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4.2 Shifting ground

In Section 3 and in Section 4 so far, we have begun with the questions of how and why humans found their way to oceanic islands, and how other living
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8.3.3 Reactive ion etching: chlorine/argon plasma etching of aluminium

In a reactive ion etch (RIE), a chemical reaction is used to weaken the bonding of the surface of the material and assist the sputtering process. This combines the high rate and selectivity of a gas-phase etch with the directionality of a sputter etch.

For example, consider aluminium etched anisotropically by a Cl2/Ar mixed-gas plasma, which etches at up to 1 μm min−1:

  • Power pumped into the plasma breaks the gases up, rel
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1.5 Photocapacitors as pixels

Perhaps you can also imagine an image-capturing array made up of MOS photocapacitor pixels. It's well within the scope of microelectronics to fabricate such an array of virtually identical, isolated MOS structures that would translate the pattern of light intensity falling on it into a pattern of charge. There's more to it than that, though, because:

  • each capacitor must be simultaneously connected to a power supply that provides the reverse bias

    <
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1.3 The capacity of an MOS structure to store charge

Figure 1 shows a schematic section through an MOS structure and sets up a colour scheme that distinguishes the different layers. In this case the M-layer is provided by heavily doped polysilicon and the semiconductor base material is p-type silicon.


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1.1 Conductor–insulator–semiconductor structures

A forensic examination of the inside of any silicon chip would reveal a miniature network of metal tracks criss-crossing on several levels, separated by insulating layers of silicon dioxide and periodically stitched down to the underlying tracks and the underlying silicon. Down in the silicon proper there is an intricate pattern of islands of p-type material in pockets of n-type material and vice versa. The precision and regularity of the patterns of different materials tells of a highly soph
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References

Collins, S., Ghey, J. and Mills, G. (1989) The Professional Engineer in Society, London: Jessica Kingsley Publishers.
Foster, J., with Corby, L. (illustrator) (1996) How to Get Ideas, San Francisco: Berrett-Koehler Publishers, Inc.
Haaland, J., Wingert, J. and Olson, B. A. (1963) ‘Force required to activate switches, maximum finger pushing force, and coeffici
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8 Summary

We have seen how a solution falls into one of three categories (innovation by context, innovation by development, and routine solution) according to the need that drives it. Furthermore, the need is shown to be the point of reference that should be kept in sight throughout the process of finding solutions. Unless the need is accurately stated, the ideal solution cannot be obtained – a case of ‘garbage in, garbage out’.

We have examined the process of finding a solution step by ste
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