A type of → algorithm that dynamically achieves high
→ resolution in localized regions of multidimensional
→ numerical simulations.
AMR provides a higher → accuracy solution at
lower costs, through an automatically → optimal
distribution of → grid points for the
computation region. It relies on locally refined mesh or mesh
patches to increase the resolution of an underlying
coarse mesh only where needed.
It can alleviate some of the complexities of the generation of high
quality grid and reduce the number of → iterations of
"trial-and-error" between the grid generation and solution
required for tailoring the grid to the specification of a
problem. Thus, it can offer orders of magnitude saving in
computational and storage costs over an equivalent uniformly refined
mesh. AMR was originally developed for → inviscid,
→ compressible flow (Berger et al., 1984,
Adaptive Mesh Refinement for Hyperbolic Partial Differential
Equations. J. Comp. Phy., 53, 484). It
has been extended to solve → Navier-Stokes equations,
time dependent problems and more. Several
AMR techniques have been developed and applied to compressible flow fields to capture
characteristics at the strong gradient or discontinuous regions requiring higher space resolution,
such as regions involving → shock waves,
vortices (→ vortex), and
→ wakes
(see, e.g., Qingluan Xue, "Development of Adaptive Mesh Refinement Scheme and
Conjugate Heat Transfer Model for Engine Simulations" (2009), Iowa State Univ., Graduate
Theses and Dissertations, Paper 10678).
See also → Smoothed Particle Hydrodynamics.

A set → if and only if (iff)
for any two points in the → set,
the line through them is contained in the set. In other words, for any two points in
the set, their → affine combinations
are in the set itself.

General: The act of confining; the state of being confined.
Physics:
A property of quantum electrodynamics whereby quarks cannot exist as free
particles, but are forever bound into protons, neutrons, etc.

1) To state or set forth the meaning of (a word, concept, etc.).
2) To explain or identify the nature or essential qualities of.
3) To fix or mark the boundaries or extent of.

From O.Fr. définir "to end, determine," from L. definire
"to limit, determine, explain," from → de- + finire
"to bound, limit," from finis "boundary."

Hedâridan, infinitive from Semnâni hedâr "boundary (between pieces of
lands)," Tabari hedâri "boundary, border," may be related to
Av. haêtav- "dam, dike," Skt. setu- "a ridge of earth, bank, dike, dam,
bridge."

defined

هداریده

hedâridé

Fr.: défini

1) Clearly characterized or fixed.
2) Showing clearly the outline or profile or boundary.
3) Computer science: A variable having received a value prior to a given point in
a program.

M.E. fin, from O.Fr. fin "perfected, of highest quality," from
L. finis "end, limit."

Nâzok "thin, slender, subtle,"
from Mid.Pers. nâzuk "tender, gentle," variant nâzik, from
nâz "joy, pride, glory" + → -ik.

fine dust

ریزگرد، غبار ِ نازک

rizgard, qobâr-e nâzok

Fr.: poussière fine

Meteorology: An → inhomogeneous
→ mixture of tiny, part → solid,
part → liquid or → gaseous
→ particles that are, in average, smaller than ten
→ microns. The constituents are soot, heavy metals,
organic substances, and dioxins. The smaller
these dust particles, the deeper they penetrate into the
lung.
Larger particles are
intercepted by mucous membrane in nose, mouth, and throat but
smaller particles can penetrate the smallest lung bronchioles
and may cause severe damage (various respiratory disorders, lung cancer)
→ particulate matter.

Closely spaced components seen at high resolution in a
→ spectral line. The phenomenon is explained by the fact
that instead of a single → energy level corresponding to a
given value of the → quantum numbern,
there are actually a number of energy levels lying close to one another.
→ fine-structure constant,
→ fine-structure line.

In spectroscopy, the → splitting of a spectral line into a
number of very thin components. It results from a small perturbation in the
energy levels of atoms or molecules due to the magnetic dipole-dipole
interaction arising from the interaction of the nuclear
→ magnetic moment with the
→ spin of the electron. It can be observed
only at high spectral dispersion. → fine structure.