Made fig_invariance_rect_lp.pdf and corresponding appendix figure.

Adjusted fig_invariance_log_hp.pdf with 2nd yaxis in dB.

Co-authored-by: Copilot <copilot@github.com>

main.tex

@@ -570,6 +570,37 @@ intensity variations. The two mechanisms each comprise a nonlinear signal
 transformation followed by a linear signal transformation but differ in the
 specific operations involved, as outlined in the following sections.
 
+\subsection{Full-wave rectification \& lowpass filtering}
+
+\begin{figure}[!ht]
+    \centering
+    \includegraphics[width=\textwidth]{figures/fig_invariance_rect_lp.pdf}
+    \caption{\textbf{Intensity invariance by logarithmic compression and
+                     adaptation is restricted by the noise floor.}
+                     Synthetic input $\filt(t)$ consists of song component
+                     $\soc(t)$ scaled by $\sca$ with (\figc{} and \figd) or
+                     without (\figa{} and \figb) additive noise component
+                     $\noc(t)$. Input $\filt(t)$ is transformed into envelope
+                     $\env(t)$, logarithmically compressed envelope $\db(t)$,
+                     and intensity-adapted envelope $\adapt(t)$.
+                     \textbf{Left}:~$\env(t)$, $\db(t)$, and $\adapt(t)$ for
+                     different scales $\sca$.
+                     \textbf{Right}:~Ratios of the standard deviation of
+                     $\env(t)$, $\db(t)$, and $\adapt(t)$ relative to the
+                     respective reference standard deviation $\sigma_{\eta}$
+                     for input $\filt(t)=\noc(t)$.
+                     \figa{} and \figb:~Ideally, if $\filt(t)=\sca\cdot\soc(t)$, then
+                     $\adapt(t)$ is intensity-invariant across all $\sca$.
+                     \figc{} and \figd:~In practice, if
+                     $\filt(t)=\sca\cdot\soc(t)+\noc(t)$, the intensity
+                     invariance of $\adapt(t)$ is limited to sufficiently large
+                     $\sca$. Shaded area indicates saturation of $\adapt(t)$ at
+                     $95\,\%$ curve span.
+                     }
+    \label{fig:inv_rect-lp}
+\end{figure}
+\FloatBarrier
+
 \subsection{Logarithmic compression \& spike-frequency adaptation}
 
 The first notable emergence of intensity invariance along the model pathway
@@ -899,6 +930,15 @@ initiation of one behavior over another is categorical (e.g. approach/stay)
 \end{figure}
 \FloatBarrier
 
+\begin{figure}[!ht]
+    \centering
+    \includegraphics[width=\textwidth]{figures/fig_invariance_rect-lp_appendix.pdf}
+    \caption{\textbf{}
+                     }
+    \label{}
+\end{figure}
+\FloatBarrier
+
 \begin{figure}[!ht]
     \centering
     \includegraphics[width=\textwidth]{figures/fig_invariance_log-hp_appendix.pdf}
@@ -935,4 +975,40 @@ initiation of one behavior over another is categorical (e.g. approach/stay)
 \end{figure}
 \FloatBarrier
 
+\begin{figure}[!ht]
+    \centering
+    \includegraphics[width=\textwidth]{figures/fig_kernel_sd_perc_thresh_lp_appendix.pdf}
+    \caption{\textbf{}
+                     }
+    \label{}
+\end{figure}
+\FloatBarrier
+
+\begin{figure}[!ht]
+    \centering
+    \includegraphics[width=\textwidth]{figures/fig_kernel_sd_perc_full_appendix.pdf}
+    \caption{\textbf{}
+                     }
+    \label{}
+\end{figure}
+\FloatBarrier
+
+\begin{figure}[!ht]
+    \centering
+    \includegraphics[width=\textwidth]{figures/fig_kernel_sd_perc_short_appendix.pdf}
+    \caption{\textbf{}
+                     }
+    \label{}
+\end{figure}
+\FloatBarrier
+
+\begin{figure}[!ht]
+    \centering
+    \includegraphics[width=\textwidth]{figures/fig_kernel_sd_perc_field_appendix.pdf}
+    \caption{\textbf{}
+                     }
+    \label{}
+\end{figure}
+\FloatBarrier
+
 \end{document}