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6.5 Military and humanitarian interventionism

While the ICC may be the most radical cosmopolitan effort at global justice institution-building so far, it is not the only one. The move towards cosmopolitan global institutions that extend beyond the UN's original goals and values has speeded up during the 1990s. Cosmopolitans would contend that international institution-building does not necessarily lead to more interventionism. Communitarians such as Chandler see as significant that in the field of international human rights interventioni
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6.4 International retributive justice

A further difference between communitarians and cosmopolitans arises over the question of retributive justice. Communitarians think that it is the responsibility of each state to uphold justice. Collectively, states can pursue international justice through the auspices of the UN, and are answerable to each other, to public opinion and to NGOs. However, there is no basis for claims to universal jurisdiction, and to deal with matters not found in specific states (such as piracy), or that cross
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4.2 Social and political justice

A particularly important set of debates arises in relation to different notions of distributive justice. Do notions of distributive justice apply to the rights of individuals and the acts that they commit, or do they also apply to states of affairs, to the pattern of the results arising from those actions? In the former case, an outcome is just or unjust if it arises from just or unjust actions; whereas in the latter, the principles of justice apply to the pattern of outcomes. This latter not
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Keep on learning

Study another free course

There are more than 800 courses on OpenLearn for you to
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Approaches to software development
This free course, Approaches to software development, presents an engineering approach to the development of software systems – a software engineering approach. The course pays particular attention to issues of software quality, in terms of both product (what is built) and process (how we build it). First published on Mon, 18 Jun 2018 as Author(s): Creator not set

5.4.2 Leadership expectations

  • Largely because of expectations created in childhood (our 'inner child of the past'), we have many unconscious expectations of leaders, and may well harbour resentments, anxieties, suspicions, subservience, passive resistances and attitudes to leadership that have little relationship to current adult realities.

  • The leader needs to be able to manage these feelings and his or her own responses to them.

  • Leaders will tend to emerge
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3.2.4 Functional and team roles

When individuals are being selected for membership of a team, the choice is usually made on the basis of task-related issues, such as their prior skills, knowledge, and experience. However, team effectiveness is equally dependent on the personal qualities and attributes of individual team members. It is just as important to select for these as well.

When we work with other people in a group or team we each bring two types of role to that relationship. The first, and more obvious, is our
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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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4 Excitation

For a player to be able to sound a musical instrument, there must be a means of inputting energy to set up the vibration. This energy may be introduced in a short, sharp burst or continuously over a period of time.

In the case of brass instruments such as the trumpet and trombone, and woodwind instruments such as the flute and oboe, the player feeds in energy by blowing air into the instrument. The energy can be supplied in a short burst – in which case short-lived ‘staccato’ note
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5.4 Sedimentation

When water has little or no movement, suspended solids sink to the bottom under the force of gravity and form a sediment. You will recall that we discussed a similar process in estuaries, with solids separating from the water. This process is called sedimentation. In water treatment it is used to remove solids from waters which are high in sediment content, and also to remove particles rendered settleable by coagulation and flocculation.

The theory of sedimentation would
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5.3 Coagulation and flocculation

Coagulation is always considered along with flocculation and is used to remove particles which cannot be removed by sedimentation or filtration alone. These particles are usually less than 1 μm in size and are termed colloids. They have poor settling characteristics and are responsible for the colour and turbidity of water. They include clays, metal oxides, proteins, micro-organisms and organic substances such as those that give the brown coloration to water from 'peaty' catc
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5.2 Preliminary treatment

The abstracted water is first screened to remove suspended and floating debris, such as leaves or branches, which could interfere with the operation of machinery in the treatment works. The water may then enter a preliminary settlement tank or storage reservoir. It then passes through screens again and goes to the treatment works. Screens may be classified by the size of their openings as coarse or fine, and may be in the forms of bars or continuous belts. Coarse screens are u
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5.1 Introduction

Water for public supply can be obtained from underground sources by wells sunk into aquifers, or from surface sources such as purpose-built reservoirs or lakes (collecting rainwater run-off or water from streams) and rivers. The safety of the water is of utmost concern – several million people die each year after consuming contaminated water. The primary aim in water treatment is the elimination of any pathogenic micro-organisms present. All the above-mentioned sources can be subject to pol
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4.7 Summary

Water in its 'natural' state supports a complex, yet fragile, ecosystem. The ability of natural watercourses to sustain aquatic life depends on a variety of physical, chemical and biological conditions. Biodegradable compounds, nutrients and dissolved oxygen must be available for the metabolic activities of the algae, fungi, bacteria and protozoa which are at the lowest level of the food chain. In addition, plant and animal growth cannot occur outside narrow ranges of temperature and pH. Susp
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4.6 Tidal rivers and estuaries

Most of the major cities and harbours in the world are located on estuaries. The estuarine ecosystem is a unique intermediate between the sea, the land and fresh water.

A rather precise definition of an estuary is 'a semi-enclosed coastal body of water, which has a free connection with the open sea, and within which sea water is measurably diluted with fresh water derived from land drainage'. This excludes large bays with little or no freshwater flow, and large brackish seas and inland
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3.5.5 Biological indicators

A great many biological species and individuals occur in normal streams. These often differ markedly in their sensitivity to environmental factors, and likewise the tolerances of various species to different types of pollution vary considerably. The major groups of organisms that have been used as indicators of environmental pollution include bacteria, fungi, protozoa, algae, higher plants, macroinvertebrates and fish. The benthic 'bottom living' macroinvertebrates are particularly suitable a
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3.5.4 Fungi

Fungi (e.g. species such as Penicillium which are used for manufacture of antibiotics, and yeast) are generally unicellular non-photosynthetic organisms which can tolerate acid conditions. They are capable of degrading highly complex organic compounds. They utilise much the same food sources as bacteria but they require less nitrogen since their protein content is lower. Fungi play an important role in sewage treatment.

In polluted water, particularly near to a se
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3.5.3 Protozoa

Protozoa are microscopic single cell animals. They utilise solid substances and bacteria as a food source. They can only function aerobically, and in a stream which contains little organic degradable matter they can become a predominant microbial type. They play an important part in sewage treatment where they remove free-swimming bacteria and help to produce a clear effluent.

In an aquatic environment, there are three main types of protozoa:

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3.5.2 Bacteria

Bacteria are organisms of special significance to the study of clean and polluted waters because they break down organic matter. While most of them are not harmful to humans, some bacteria (e.g. Clostridium) are pathogenic. Most bacteria are retained on a filter of pore size 0.45 μm and all bacteria are trapped on a filter of 0.22 μm. They are important in sewage treatment, and in solid waste disposal. They are extremely abundant in almost all parts of the aquatic env
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3.5.1 Algae

Algae are photosynthetic organisms that are generally aquatic; they are primary producers. Many freshwater algae are of microscopic size, but when amassed can be seen as a green, brown or blue-green scum. Blue-green algae are capable of producing toxins and these have caused the death of wild animals, farm livestock and domestic pets which have consumed the contaminated water. The toxins can produce a painful rash on human skin. The extract below shows what happened off the west coast
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