  The experimental data taken from both Drell-Yan and deep-inelastic scattering
(DIS) experiments suggest a sign-change in $\bar d(x) - \bar u(x)$ flavor
asymmetry in the proton at large values of momentum fraction $x$. In this work,
we present a phenomenological study of $\bar d(x) - \bar u(x)$ flavor
asymmetry. First, we extract the $\bar d(x)-\bar u(x)$ distribution using the
more recent data from the BONuS experiment at Jefferson Lab on the ratio of
neutron to proton structure functions, $F_2^n/F_2^p$, and show that it
undergoes a sing-change and becomes negative at large values of momentum
fraction $x$, as expected. The stability and reliability of our obtained
results have been examined by including target mass corrections (TMCs) as well
as higher twist (HT) terms which are particularly important at the large-$x$
region at low Q$^2$. Then, we calculate the $\bar d(x) - \bar u(x)$
distribution using the Brodsky, Hoyer, Peterson, and Sakai (BHPS) model and
show that if one chooses a mass for the down quark smaller than the one for the
up quark it leads to a better description for the Fermilab E866 data. In order
to prove this claim, we determine the masses of down and up sea quarks by
fitting to the available and up-to-date experimental data for the $\bar
d(x)-\bar u(x)$ distribution. In this respect, unlike the previous performed
theoretical studies, we have shown that this distribution has a sign-change at
$x>0.3$ after evolution to the scale of available experimental data.
