\documentclass{article}
\usepackage{com.braju.graphicalmodels}

\catcode`\@=11%

\pagestyle{empty}

\begin{document}
\TeXtoEPS

\LARGE
\psset{unit=10mm,arrowscale=1.5,linewidth=1.5pt}
\begin{pspicture}(0,0)(8,8)%\showgrid
  \SpecialCoor

  \rput[bl](3,7){\ovalnode{Oil}{Oil}}
  \rput[bl](5,3){\dianode{Utility}{Utility}}
  \rput[bl](7,5){\rnode{Drill}{\psframebox[]{Drill}}}
  \rput[bl](6.5,7){\ovalnode{Sound}{Sound}}


  \ncline[arrows=->]{Oil}{Utility}
  \ncline[arrows=->]{Drill}{Utility}
  \ncline[arrows=->]{Oil}{Sound}
  \ncline[arrows=->]{Sound}{Drill}

\end{pspicture}

\endTeXtoEPS
\end{document}