exponential decay

(redirected from Exponential decline)
Also found in: Dictionary, Thesaurus.

exponential decay

[‚ek·spə′n en·chəl di′kā]
(physics)
The decrease of some physical quantity according to the exponential law N (t)= N0 e -t, where τ is a constant called the decay time.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
References in periodicals archive ?
If [C.sub.m] = 0 at large t because of drift with water flow, [C.sub.im] decreases as [C.sub.im] ~ [e.sup.-[beta]t] that is, an exponential decline.
Now let us discuss the transition time [T.sub.t] at which the decline of P(t) transits from a power-law form to an exponential decline form.
Withholding P fertiliser for 21-26 years on sheep-grazed pasture led to an exponential decline in exchangeable P despite expected zero or slightly positive P balances; on one of the two sites this was accompanied by a decrease in [P.sub.i] and increase in [P.sub.org], resulting in no change in TP.
Perhaps the onus of proof, in distinguishing between an exponential decline and a humped soil production function, rests with the former, because one cannot rule out a humped function without shallow or exposed saprolite erosion rates depicting an exponential decline in soil production.
Furthermore, field evidence from a number of authors supports the theory for the exponential decline in bedrock lowering at depths greater than that where soil production is maximised.
The rate of exponential decline in the relative proportions of female to male workers is given by [psi] [congruent] 0.6.
We can, however, test the prediction of an exponential decline in the relative proportion of women as one moves up the management hierarchy and estimate the impact of hierarchical discrimination on wages using the decomposition formula derived above.
Given exponential decline, constant pumping costs, and data on (1 - R) [P.sub.[T.sub.1]] [q.sub.[T.sub.1]] in the final period, we have an estimate of production costs per period.
With the assumption of exponential decline, we can write another expression for [q.sub.[T.sub.0]] as:
In general, rate of cross-fertilization in white maize population with distance to the pollen source was well represented by both exponential and modified exponential decline functions.
The exponential and modified exponential decline models for the data: Y = 27.67[e.sup.-0.4098X] or Y = 28.13[e.sup.-0.464X] + 0.52, both models with [R.sup.2] = 0.64, P < 0.01 for downwind; Y = 15.38[e.sup.-0.6468X] or Y = 14-17[e.sup.-0.5139X] + 0.33 with [R.sup.2] = 0.58, P < 0.01 for upwind directions.
Simplistic assumptions were made about exponential decline of emissions and dispersion over the first 10 days of the accident (13).