Add information. How to refine the mesh further.

21_distributed-memory.tex

@@ -392,19 +392,19 @@ metric if you switch this feature on (\texttt{hotspot}, e.g.).
 
 \subsection{Meshes for weak and strong scaling}
 
-ExaHyPE distributes work by decomposing the tripartitioned spacetree into
+\exahype distributes work by decomposing the tripartitioned spacetree into
 subtrees that are deployed to worker processes.
 Only subtrees that overlap with the computational domain are deployed.
 This constraint can be used to steer work distribution.
 
-ExaHyPE can scale the bounding box such that \texttt{outside\_cells\_left} and/or \texttt{outside\_cells\_right} cells are placed outside of the 
+\exahype can scale the bounding box such that \texttt{outside\_cells\_left} and/or \texttt{outside\_cells\_right} cells are placed outside of the 
 domain while the latter is still resolved as accurately as specified in the spec file.
 
 Furthermore, there is an option to place exactly \texttt{ranks\_per\_dimension" on the coarse grid}. 
 (Note: This overrules \texttt{outside\_cells\_right} but not \texttt{outside\_cells\_left}. 
 This feature is particular interesting for weak scaling experiments as it can scale the number of cells per dimension
 of a mesh by arbitrary integers.
-An example is given below:
+An example is given in Fig. \ref{fig:weak-scaling}:
 
 \begin{figure}[h]
 \begin{center}
@@ -416,23 +416,25 @@ An example is given below:
   \includegraphics[width=0.4\textwidth]{sketches/weak-scaling-8.pdf}
 \end{center} 
 \caption{Weak scaling experiment growing the domain by factors $1$, $2^d$, $4^d$, and $8^d$. \texttt{ranks\_per\_dimension} is chosen 1,2,4,8.}
-}
+\label{fig:weak-scaling}
 \end{figure}
 
 The bounding box scaling controls can be used to create interesting meshes as 
-the $36^d$ cell mesh given below. This mesh was created with 9 outside cells
+the $36^d$ cell mesh shown in Fig. \ref{fig:strong-scaling}. This mesh was created with 9 outside cells
 on the left side and 12 ranks per dimension. The mesh
 is interesting since it can be perfectly distributed among
 $2^d$, $4^d$, and $12^d$ processes.
 
+The same mesh refined by a factor $3^i$, $i \leq 1$ can be constructed if $3^i \times 9$ bounding box outside cells
+are placed to the left of the domain.
+
 \begin{figure}[h]
 \begin{center}
   \includegraphics[width=0.5\textwidth]{sketches/strong-scaling-grid-223.pdf}
 \end{center} 
-\caption{%
-  A grid with $36^d$ cells on the coarse grid which allows to use $1$, $2^d$, $4^d$, and $12^d$ ranks
-  to uniformly distribute the load.
-}
+\caption{A grid with $36^d$ cells on the coarse grid which allows to use $1$, $2^d$, $4^d$, and $12^d$ ranks
+to uniformly distribute the load.}
+\label{fig:strong-scaling}
 \end{figure}
 
 \section{MPI troubleshooting and inefficiency patterns}