| slovo | definícia |
entropy
(encz) | entropy,entropie [eko.] RNDr. Pavel Piskač |
entropy
(encz) | entropy,střední množství informace web |
Entropy
(gcide) | Entropy \En"tro*py\, n. [Gr. ? a turning in; ? in + ? a turn,
fr. ? to turn.] (Thermodynamics)
A certain property of a body, expressed as a measurable
quantity, such that when there is no communication of heat
the quantity remains constant, but when heat enters or leaves
the body the quantity increases or diminishes. If a small
amount, h, of heat enters the body when its temperature is t
in the thermodynamic scale the entropy of the body is
increased by h / t. The entropy is regarded as measured from
some standard temperature and pressure. Sometimes called the
thermodynamic function.
[1913 Webster]
The entropy of the universe tends towards a maximum.
--Clausius.
[1913 Webster] |
entropy
(gcide) | Heat \Heat\ (h[=e]t), n. [OE. hete, h[ae]te, AS. h[=ae]tu,
h[=ae]to, fr. h[=a]t hot; akin to OHG. heizi heat, Dan. hede,
Sw. hetta. See Hot.]
1. A force in nature which is recognized in various effects,
but especially in the phenomena of fusion and evaporation,
and which, as manifested in fire, the sun's rays,
mechanical action, chemical combination, etc., becomes
directly known to us through the sense of feeling. In its
nature heat is a mode of motion, being in general a form
of molecular disturbance or vibration. It was formerly
supposed to be a subtile, imponderable fluid, to which was
given the name caloric.
[1913 Webster]
Note: As affecting the human body, heat produces different
sensations, which are called by different names, as
heat or sensible heat, warmth, cold, etc., according to
its degree or amount relatively to the normal
temperature of the body.
[1913 Webster]
2. The sensation caused by the force or influence of heat
when excessive, or above that which is normal to the human
body; the bodily feeling experienced on exposure to fire,
the sun's rays, etc.; the reverse of cold.
[1913 Webster]
3. High temperature, as distinguished from low temperature,
or cold; as, the heat of summer and the cold of winter;
heat of the skin or body in fever, etc.
[1913 Webster]
Else how had the world . . .
Avoided pinching cold and scorching heat! --Milton.
[1913 Webster]
4. Indication of high temperature; appearance, condition, or
color of a body, as indicating its temperature; redness;
high color; flush; degree of temperature to which
something is heated, as indicated by appearance,
condition, or otherwise.
[1913 Webster]
It has raised . . . heats in their faces. --Addison.
[1913 Webster]
The heats smiths take of their iron are a blood-red
heat, a white-flame heat, and a sparkling or welding
heat. --Moxon.
[1913 Webster]
5. A single complete operation of heating, as at a forge or
in a furnace; as, to make a horseshoe in a certain number
of heats.
[1913 Webster]
6. A violent action unintermitted; a single effort; a single
course in a race that consists of two or more courses; as,
he won two heats out of three.
[1913 Webster]
Many causes . . . for refreshment betwixt the heats.
--Dryden.
[1913 Webster]
[He] struck off at one heat the matchless tale of
"Tam o' Shanter." --J. C.
Shairp.
[1913 Webster]
7. Utmost violence; rage; vehemence; as, the heat of battle
or party. "The heat of their division." --Shak.
[1913 Webster]
8. Agitation of mind; inflammation or excitement;
exasperation. "The heat and hurry of his rage." --South.
[1913 Webster]
9. Animation, as in discourse; ardor; fervency; as, in the
heat of argument.
[1913 Webster]
With all the strength and heat of eloquence.
--Addison.
[1913 Webster]
10. (Zool.) Sexual excitement in animals; readiness for
sexual activity; estrus or rut.
[1913 Webster +PJC]
11. Fermentation.
[1913 Webster]
12. Strong psychological pressure, as in a police
investigation; as, when they turned up the heat, he took
it on the lam. [slang]
[PJC]
Animal heat, Blood heat, Capacity for heat, etc. See
under Animal, Blood, etc.
Atomic heat (Chem.), the product obtained by multiplying
the atomic weight of any element by its specific heat. The
atomic heat of all solid elements is nearly a constant,
the mean value being 6.4.
Dynamical theory of heat, that theory of heat which assumes
it to be, not a peculiar kind of matter, but a peculiar
motion of the ultimate particles of matter.
Heat engine, any apparatus by which a heated substance, as
a heated fluid, is made to perform work by giving motion
to mechanism, as a hot-air engine, or a steam engine.
Heat producers. (Physiol.) See under Food.
Heat rays, a term formerly applied to the rays near the red
end of the spectrum, whether within or beyond the visible
spectrum.
Heat weight (Mech.), the product of any quantity of heat by
the mechanical equivalent of heat divided by the absolute
temperature; -- called also thermodynamic function, and
entropy.
Mechanical equivalent of heat. See under Equivalent.
Specific heat of a substance (at any temperature), the
number of units of heat required to raise the temperature
of a unit mass of the substance at that temperature one
degree.
Unit of heat, the quantity of heat required to raise, by
one degree, the temperature of a unit mass of water,
initially at a certain standard temperature. The
temperature usually employed is that of 0[deg] Centigrade,
or 32[deg] Fahrenheit.
[1913 Webster] |
entropy
(wn) | entropy
n 1: (communication theory) a numerical measure of the
uncertainty of an outcome; "the signal contained thousands
of bits of information" [syn: information, {selective
information}, entropy]
2: (thermodynamics) a thermodynamic quantity representing the
amount of energy in a system that is no longer available for
doing mechanical work; "entropy increases as matter and
energy in the universe degrade to an ultimate state of inert
uniformity" [syn: randomness, entropy, S] |
entropy
(foldoc) | entropy
A measure of the disorder of a system. Systems tend
to go from a state of order (low entropy) to a state of
maximum disorder (high entropy).
The entropy of a system is related to the amount of
information it contains. A highly ordered system can be
described using fewer bits of information than a disordered
one. For example, a string containing one million "0"s can be
described using run-length encoding as [("0", 1000000)]
whereas a string of random symbols (e.g. bits, or characters)
will be much harder, if not impossible, to compress in this
way.
Shannon's formula gives the entropy H(M) of a message M in
bits:
H(M) = -log2 p(M)
Where p(M) is the probability of message M.
(1998-11-23)
|
| | podobné slovo | definícia |
conformational entropy
(encz) | conformational entropy, n: |
Entropy
(gcide) | Entropy \En"tro*py\, n. [Gr. ? a turning in; ? in + ? a turn,
fr. ? to turn.] (Thermodynamics)
A certain property of a body, expressed as a measurable
quantity, such that when there is no communication of heat
the quantity remains constant, but when heat enters or leaves
the body the quantity increases or diminishes. If a small
amount, h, of heat enters the body when its temperature is t
in the thermodynamic scale the entropy of the body is
increased by h / t. The entropy is regarded as measured from
some standard temperature and pressure. Sometimes called the
thermodynamic function.
[1913 Webster]
The entropy of the universe tends towards a maximum.
--Clausius.
[1913 Webster]Heat \Heat\ (h[=e]t), n. [OE. hete, h[ae]te, AS. h[=ae]tu,
h[=ae]to, fr. h[=a]t hot; akin to OHG. heizi heat, Dan. hede,
Sw. hetta. See Hot.]
1. A force in nature which is recognized in various effects,
but especially in the phenomena of fusion and evaporation,
and which, as manifested in fire, the sun's rays,
mechanical action, chemical combination, etc., becomes
directly known to us through the sense of feeling. In its
nature heat is a mode of motion, being in general a form
of molecular disturbance or vibration. It was formerly
supposed to be a subtile, imponderable fluid, to which was
given the name caloric.
[1913 Webster]
Note: As affecting the human body, heat produces different
sensations, which are called by different names, as
heat or sensible heat, warmth, cold, etc., according to
its degree or amount relatively to the normal
temperature of the body.
[1913 Webster]
2. The sensation caused by the force or influence of heat
when excessive, or above that which is normal to the human
body; the bodily feeling experienced on exposure to fire,
the sun's rays, etc.; the reverse of cold.
[1913 Webster]
3. High temperature, as distinguished from low temperature,
or cold; as, the heat of summer and the cold of winter;
heat of the skin or body in fever, etc.
[1913 Webster]
Else how had the world . . .
Avoided pinching cold and scorching heat! --Milton.
[1913 Webster]
4. Indication of high temperature; appearance, condition, or
color of a body, as indicating its temperature; redness;
high color; flush; degree of temperature to which
something is heated, as indicated by appearance,
condition, or otherwise.
[1913 Webster]
It has raised . . . heats in their faces. --Addison.
[1913 Webster]
The heats smiths take of their iron are a blood-red
heat, a white-flame heat, and a sparkling or welding
heat. --Moxon.
[1913 Webster]
5. A single complete operation of heating, as at a forge or
in a furnace; as, to make a horseshoe in a certain number
of heats.
[1913 Webster]
6. A violent action unintermitted; a single effort; a single
course in a race that consists of two or more courses; as,
he won two heats out of three.
[1913 Webster]
Many causes . . . for refreshment betwixt the heats.
--Dryden.
[1913 Webster]
[He] struck off at one heat the matchless tale of
"Tam o' Shanter." --J. C.
Shairp.
[1913 Webster]
7. Utmost violence; rage; vehemence; as, the heat of battle
or party. "The heat of their division." --Shak.
[1913 Webster]
8. Agitation of mind; inflammation or excitement;
exasperation. "The heat and hurry of his rage." --South.
[1913 Webster]
9. Animation, as in discourse; ardor; fervency; as, in the
heat of argument.
[1913 Webster]
With all the strength and heat of eloquence.
--Addison.
[1913 Webster]
10. (Zool.) Sexual excitement in animals; readiness for
sexual activity; estrus or rut.
[1913 Webster +PJC]
11. Fermentation.
[1913 Webster]
12. Strong psychological pressure, as in a police
investigation; as, when they turned up the heat, he took
it on the lam. [slang]
[PJC]
Animal heat, Blood heat, Capacity for heat, etc. See
under Animal, Blood, etc.
Atomic heat (Chem.), the product obtained by multiplying
the atomic weight of any element by its specific heat. The
atomic heat of all solid elements is nearly a constant,
the mean value being 6.4.
Dynamical theory of heat, that theory of heat which assumes
it to be, not a peculiar kind of matter, but a peculiar
motion of the ultimate particles of matter.
Heat engine, any apparatus by which a heated substance, as
a heated fluid, is made to perform work by giving motion
to mechanism, as a hot-air engine, or a steam engine.
Heat producers. (Physiol.) See under Food.
Heat rays, a term formerly applied to the rays near the red
end of the spectrum, whether within or beyond the visible
spectrum.
Heat weight (Mech.), the product of any quantity of heat by
the mechanical equivalent of heat divided by the absolute
temperature; -- called also thermodynamic function, and
entropy.
Mechanical equivalent of heat. See under Equivalent.
Specific heat of a substance (at any temperature), the
number of units of heat required to raise the temperature
of a unit mass of the substance at that temperature one
degree.
Unit of heat, the quantity of heat required to raise, by
one degree, the temperature of a unit mass of water,
initially at a certain standard temperature. The
temperature usually employed is that of 0[deg] Centigrade,
or 32[deg] Fahrenheit.
[1913 Webster] |
conformational entropy
(wn) | conformational entropy
n 1: entropy calculated from the probability that a state could
be reached by chance alone |
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