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\name{max_twa_parent}
\alias{max_twa_parent}
\alias{max_twa_sfo}
\alias{max_twa_fomc}
\alias{max_twa_dfop}
\alias{max_twa_hs}
\title{
Function to calculate maximum time weighted average concentrations from kinetic models fitted with mkinfit
}
\description{
This function calculates maximum moving window time weighted average concentrations
(TWAs) for kinetic models fitted with \code{\link{mkinfit}}. Currently, only
calculations for the parent are implemented for the SFO, FOMC, DFOP and HS models,
using the analytical formulas given in the PEC soil section of the FOCUS
guidance.}
\usage{
max_twa_parent(fit, windows)
max_twa_sfo(M0 = 1, k, t)
max_twa_fomc(M0 = 1, alpha, beta, t)
max_twa_dfop(M0 = 1, k1, k2, g, t)
max_twa_hs(M0 = 1, k1, k2, tb, t)
}
\arguments{
\item{fit}{
An object of class \code{\link{mkinfit}}.
}
\item{windows}{
The width of the time windows for which the TWAs should be calculated.
}
\item{M0}{
The initial concentration for which the maximum time weighted
average over the decline curve should be calculated. The default
is to use a value of 1, which means that a relative maximum time
weighted average factor (f_twa) is calculated.
}
\item{k}{
The rate constant in the case of SFO kinetics.
}
\item{t}{
The width of the time window.
}
\item{alpha}{
Parameter of the FOMC model.
}
\item{beta}{
Parameter of the FOMC model.
}
\item{k1}{
The first rate constant of the DFOP or the HS kinetics.
}
\item{k2}{
The second rate constant of the DFOP or the HS kinetics.
}
\item{g}{
Parameter of the DFOP model.
}
\item{tb}{
Parameter of the HS model.
}
}
\value{
For \code{max_twa_parent}, a numeric vector, named using the \code{windows} argument.
For the other functions, a numeric vector of length one (also known as 'a
number').
}
\examples{
fit <- mkinfit("FOMC", FOCUS_2006_C, quiet = TRUE)
max_twa_parent(fit, c(7, 21))
}
\references{
FOCUS (2006) \dQuote{Guidance Document on Estimating Persistence and
Degradation Kinetics from Environmental Fate Studies on Pesticides in EU
Registration} Report of the FOCUS Work Group on Degradation Kinetics,
EC Document Reference Sanco/10058/2005 version 2.0, 434 pp,
\url{http://esdac.jrc.ec.europa.eu/projects/degradation-kinetics}
}
\author{
Johannes Ranke
}
\keyword{ manip }
|
