report: application: document "explore" tab in spark ui

doc/report/applications-screenshots.tex

+% https://tex.stackexchange.com/questions/196481/problem-on-subfigure-2x2
+
+\begin{figure*}
+    \centering
+    \begin{subfigure}[]{0.475\textwidth}
+        \centering
+        \shadowbox{\includegraphics[width=\textwidth]{figs/explore1.png}}
+        \caption{Listing of all contributors in the data set. Clicking
+          on a given author shows their individual contributions.}
+    \end{subfigure}
+    \hfill
+    \begin{subfigure}[]{0.475\textwidth}
+        \centering
+        \shadowbox{\includegraphics[width=\textwidth]{figs/explore2.png}}
+        \caption{Listing works a given contributor worked on.\\}
+    \end{subfigure}
+    \vskip\baselineskip{}
+    \begin{subfigure}[]{0.475\textwidth}
+        \centering
+        \shadowbox{\includegraphics[width=\textwidth]{figs/explore3.png}}
+        \caption{Examining a single node in the data set. From \texttt{ulo:sourceref}
+          we can infer the original URI of this object.}
+    \end{subfigure}
+    \hfill
+    \begin{subfigure}[]{0.475\textwidth}
+        \centering
+        \shadowbox{\includegraphics[width=\textwidth]{figs/explore4.png}}
+        \caption{The original source code for a given node in our data set.\\}\label{fig:isrc}
+    \end{subfigure}
+    \caption{Exploring the Isabelle~export~\cite{uloisabelle} with a rudimentary
+      web interface.}\label{fig:appss}
+\end{figure*}

doc/report/applications.tex

@@ -2,7 +2,7 @@
 
 With programming endpoints in place, we can now query the data set
 containing both Isabelle and Coq exports stored in {GraphDB}. We
-experimented with two kinds of applications that talk to a GraphDB
+experimented with the following applications that talk to a GraphDB
 endpoint.
 
 \begin{itemize}
@@ -11,6 +11,10 @@ endpoint.
       thirds of existing ULO predicates were not taken advantage of
       (Section~\ref{sec:expl}).
 
+    \item Providing an interactive interface for browsing the data
+      set. Our implementation is limited to listing basic
+      information about contributors and their work.
+
     \item We investigated queries that could be used to extend the
       system into a larger tetrapodal search system. While some
       organizational queries have obvious canonical solutions others
@@ -73,6 +77,44 @@ expect predicates to be evenly distributed in the data set. This is
 something to keep in mind especially as the number of ULO exports
 increases.
 
+\subsection{Interactive Exploration}
+
+Our second application wants to illustrate how to browse an ULO data
+set interactively. For this purpose, we developed a web front end that
+allows us to browse contributions by author. For this tool, we used
+the RDF4J Endpoint, the application itself is implemented in
+Java. Figure~\ref{fig:appss} shows four screenshots of the current
+version.  Once the user has selected a given contribution, we list
+some basic information about that object of formal knowledge, such as
+type (e.g.\ lemma or corollary) and references to other objects in the
+knowledge base.
+
+\input{applications-screenshots.tex}
+
+This application is interesting because similar approaches could be
+applied when designing IDE~integration for working with organizational
+knowledge. Given some object in a document identified by an URI, we
+can look at how that object is connected to other objects in the
+knowledge graph. We can also connect the dots back to the original
+source. In our case, we implemented translation from the
+\texttt{ulo:sourceref} predicate as used in the Isabelle
+export~\cite{uloisabelle} to the original Isabelle source
+(Figure~\ref{fig:isrc}). This is convenient for the user, but required
+some extra work for us as application implementors. The reason for
+this is that the format of \texttt{ulo:sourceref} is not well-defined,
+rather it is up to implementors of library exporters how to format
+source references. The consequence is that for each export, developers
+of front ends will need to write custom code for finding the original
+source. Maybe it would be a reasonable requirement for
+\texttt{ulo:sourceref} to have a well-defined format, ideally a
+``real'' URI on the open web, if that is applicable for a given
+library.
+
+In summary, while translating from \texttt{ulo:sourceref} to oriental
+URI introduced some extra work, implementing this application was easy
+and straight-forward. Implementing similar features for other environments
+should not be very difficult.
+
 \subsection{Querying for Tetrapodal Search}\label{sec:tetraq}
 
 Various queries for a tetrapodal search system were previously

doc/report/report.tex

 \documentclass[a4paper]{scrartcl}
 
-\usepackage{amsmath}
 \usepackage[american]{babel}
+\usepackage{amsmath}
 \usepackage{booktabs}
 \usepackage{caption}
 \usepackage{fancybox, graphicx}
@@ -12,6 +12,7 @@
 \usepackage{lipsum}
 \usepackage{listings}
 \usepackage{multicol}
+\usepackage{mwe}
 \usepackage{placeins}
 \usepackage{subcaption}
 \usepackage{subcaption}