\setlength{\textwidth}{170mm}
\topmargin 30mm \advance  \topmargin -1in

\textheight 297mm
\advance\textheight -1in
\advance\textheight -\topmargin
\advance\textheight -\headheight
\advance\textheight -\headsep
\advance\textheight -26mm



\leftmargin 210mm \advance \leftmargin -\textwidth
\divide \leftmargin by 2 \advance \leftmargin -1in
\oddsidemargin \leftmargin \evensidemargin \leftmargin

\setlength{\parindent}{0pt} 
\addtolength{\parskip}{\baselineskip}

\def\institute#1{\gdef\@institute{#1}}
\gdef\@institute{no institute}

\def\@maketitle{%
  \newpage
  \null
  \vspace*{-8em}%
  \begin{center}%
    {\LARGE \bfseries \@title \par}%
    \vskip 2em%
    {\large
      \lineskip .5em%
      \begin{tabular}[t]{c}%
        \LARGE\@author
      \end{tabular}\par}%
    \vskip -0.9em%
    {\normalsize \@institute}%
  \end{center}%
  \par
  \vskip 2.5em}
  
  \renewenvironment{abstract}{
        %\begin{center}%
          {\itshape\bfseries \abstractname}\newline\itshape%
        %\end{center}%
     }
      {\vskip 1.9em}



\renewcommand\@seccntformat[1]{\csname the#1\endcsname. }

\renewcommand\section{\@startsection {section}{1}{\z@}%
                    {-0.2ex\@plus -0.2ex \@minus -.2ex}%
                    {0.2ex \@plus 0.2ex}%
                    {\normalfont\large\bfseries}}
\renewcommand\subsection{\@startsection{subsection}{2}{\z@}%
                    {-0.2ex\@plus -0.2ex \@minus -.2ex}%
                    {0.2ex \@plus 0.2ex}%
                    {\bfseries}}
\renewcommand\subsubsection{\@startsection{subsubsection}{3}{\z@}%
                    {-0.2ex\@plus -0.2ex \@minus -.2ex}%
                    {0.2ex \@plus 0.2ex}%
                    {\normalfont}}