Ovality

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In telecommunications and fiber optics, ovality or noncircularity is the degree of deviation from perfect circularity of the cross section of the core or cladding of the fiber.

The cross-sections of the core and cladding are assumed to a first approximation to be elliptical. Quantitatively, the ovality of either the core or cladding is expressed as \frac {2(a-b)} {a+b}, where a is the length of the major axis and b is the length of the minor axis. The dimensionless quantity so obtained may be multiplied by 100 to express ovality as a percentage. Alternatively, ovality of the core or cladding may be specified by a tolerance field consisting of two concentric circles, within which the cross section boundaries must lie.

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[edit] In chemistry

In computational chemistry, especially in QSAR[1] studies, ovality[2] refers to, a measure of how the shape of a molecule approaches a sphere (at one extreme) or a cigar shape (at the other). Ovality is described by a ratio of volume to area:

O = A/(4*pi*((3*V)/4*pi)^(2/3))

where:

A : Area V : Volume O : Ovality

The ovality of the He atom is 1.0 and HC24H (12 triple bonds) is ~1.7.

[edit] See also

[edit] External links

[edit] References

  1. ^ Leach, Andrew R. (2001). Molecular modelling: principles and applications. Englewood Cliffs, N.J: Prentice Hall. ISBN 0-582-38210-6. 
  2. ^ Hehre, Warren J.; William Sean Ohlinger (2008). Spartan'10 Tutorial and User's Guide. Irvine, CA: Wavefunction, Inc.. ISBN ISBN 1-890661-41-4. 
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