Generated .pdf file.

Change-Id: I19eb53cd64e19db54f5ae44885e7d5cd33365432
diff --git a/intro.tex b/intro.tex
index db91a84..4f2932e 100644
--- a/intro.tex
+++ b/intro.tex
@@ -62,7 +62,7 @@
 
 \begin{figure}
 \center
-\includegraphics[width=\linewidth]{figures/system-interaction}
+\includegraphics[width=\linewidth]{figures/system-interaction.pdf}
 \caption{Simplified Diagram of the Actions of NLSR's Modules}
 \label{fig:system-interaction}
 \end{figure}