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Peak Oil
Peak oil is the point in time when the maximum rate of global petroleum
extraction is reached, after which the rate of production enters terminal
decline. The concept is based on the observed production rates of individual
oil wells, and the combined production rate of a field of related oil wells.
The aggregate production rate from an oil field over time usually grows
exponentially until the rate peaks and then declines—sometimes rapidly—until
the field is depleted. This concept is derived from the Hubbert curve, and
has been shown to be applicable to the sum of a nation’s domestic production
rate, and is similarly applied to the global rate of petroleum production.
Peak oil is often confused with oil depletion; peak oil is the point of maximum
production while depletion refers to a period of falling reserves and supply.
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Global Warming
Global warming is the increase in the average temperature of the Earth's
near-surface air and oceans since the mid-20th century and its projected
continuation.
The Intergovernmental Panel on Climate Change (IPCC) concludes that most of
the observed temperature increase since the middle of the 20th century was
caused by increasing concentrations of greenhouse gases resulting from human
activity such as fossil fuel burning and deforestation. The IPCC also concludes
that variations in natural phenomena such as solar radiation and volcanoes
produced most of the warming from pre-industrial times to 1950 and had a small
cooling effect afterward. These basic conclusions have been endorsed by more
than 40 scientific societies and academies of science, including all of the
national academies of science of the major industrialized countries.
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A foreign language is a language not spoken by the people of a certain place:
for example, not only English but also Late Old Japanese is a foreign language
in Japan. It is also a language not spoken in the native country of the person
referred to, i.e. an English speaker living in Japan can say that Japanese is
a foreign language to him or her. These two characterizations do not exhaust
the possible definitions, however, and the label is occasionally applied in
ways that are variously misleading or factually inaccurate.
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Typography
Typography is the art and technique of arranging type, type design, and modifying
type glyphs. Type glyphs are created and modified using a variety of illustration
techniques. The arrangement of type involves the selection of typefaces, point size,
line length, leading (line spacing), adjusting the spaces between groups of letters
(tracking) and adjusting the space between pairs of letters (kerning).
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Color Theory
The most important problem has been a confusion between the behavior of light mixtures,
called additive color, and the behavior of paint or ink or dye or pigment mixtures,
called subtractive color. This problem arises because the absorption of light by material
substances follows different rules from the perception of light by the eye.
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Semantic Analysis
In linguistics, semantic analysis is the process of relating syntactic structures,
from the levels of phrases, clauses, sentences and paragraphs to the level of the
writing as a whole, to their language-independent meanings, removing features specific
to particular linguistic and cultural contexts, to the extent that such a project
is possible. The elements of idiom and figurative speech, being cultural, must
also be converted into relatively invariant meanings.
Latent semantic analysis (LSA) is a technique in natural language processing, in
particular in vectorial semantics, of analyzing relationships between a set of
documents and the terms they contain by producing a set of concepts related to the
documents and terms.
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