1) Of a curve, free from bumps or abrupt irregularities.
2) To modify a sequential set of numerical data by reducing the differences
in magnitude between adjacent values.

O.E. smoð "free from roughness, not harsh," of unknown origin.

Hamvâr "level, equal, an even place or thing," from
ham- "same, equally, even; together, with"
(Mid.Pers. ham-, like L. com-
and Gk. syn- with neither of which it is cognate. O.Pers./Av.
ham-, Skt. sam-; also O.Pers./Av. hama-
"one and the same," Skt. sama-, Gk. homos-;
originally identical with PIE numeral *sam-
"one," from *som-. The Av. ham- appears in various forms:
han- (before gutturals, palatals, dentals) and also hem-,
hen-) + -vâr similarity suffix.

smooth curve

خم ِ هموار

xam-e hamvâr

Fr.: courbe lisse

1) A curve which is free from abrupt fluctuations.
2) A curve if it has tangents at all points and the angle of inclination of the
tangent is a continuous function of the arc length.

A numerical method for modeling → compressible
hydrodynamic flows, which
uses particles to simulate a continuous fluid flow. Because the system of hydrodynamical
basic equations can be analytically solved only for few exceptional cases, the SPH
method provides a numerical algorithm to solve systems of coupled
→ partial differential equations
for continuous field quantities. The main advantage of the method is
that it does not require a computational grid to calculate spatial
→ derivatives and that it is a Lagrangian method, which automatically
focuses attention on fluid elements. The equations of motion and
continuity are expressed in terms of ordinary differential equations
where the body forces become classical forces between particles. This
method was first independently developed by Lucy (1977, AJ 82, 1013)
and Gingold & Monaghan (1977, MNRAS 181, 375).

Smoothed Particle Hydrodynamics, first used by Gingold & Monaghan (1977);
→ smooth; → particle;
→ hydrodynamics.

smoothed sunspot number (SSN)

شمار ِ همواریدهی ِ هورلکها

šomâr-e hamvâride-ye hurlakhâ

Fr.: nombre de taches solaires lissé

An average of 13 monthly → sunspot numbers,
centered on the month of concern.
The 1st and 13th months are given a weight of 0.5.

A low-pass filter designed to reduce the amplitude of a ripple while freely passing
the direct current obtained from a rectifier or direct-current generator.
Also known as smoothing filter.