This article is based on the talk presented at the International Workshop on
Future Linear Colliders (LCWS13) which held during November 11-15, 2013 at
Tokyo, Japan. We present several analyses related to the Higgs total width
study at ILC based on the full detector simulation of ILD, which are \eevvH
followed by \Htobb and \HtoWW. The studies show that at \unit{250}{GeV} we
can determine the Higgs total width with a relative precision of 11% and the
HWW coupling with 4.8%, whereas at \unit{500}{GeV} the expected precision
can be significantly improved to 5% and 1.2% respectively, assuming the
baseline integrated luminosities of ILC, which are \unit{250}{fb^{-1}} @
\unit{250}{GeV}, \unit{500}{fb^{-1}} @ \unit{500}{GeV}, and a beam
polarization of P(e−,e+)=(−80. A new approach of removing
pile-up particles based on multivariate method developed during those analyses
is also presented.Comment: Talk presented at the International Workshop on Future Linear
Colliders (LCWS13), Tokyo, Japan, 11-15 November 2013; based on previous note
LC-REP-2013-02