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\setlength{\headwidth}{\textwidth}
\fancyhead[R]{}%right empty
\fancyhead[L]{% left
   \includegraphics*[width=1.5cm]{rose}% irgendeine GrafikDatei
   \raisebox{5mm}{
      \begin{tabular}{l}
         \large Technical University of Berlin\\
         \small{Department of Computer Science}\\
       \end{tabular}
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}
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\begin{document}

\section{blah}
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\clearpage
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\section{blah}

\end{document} 
