diff --git a/bachelor-thesis.pdf b/bachelor-thesis.pdf
index df518d4..624e451 100644
Binary files a/bachelor-thesis.pdf and b/bachelor-thesis.pdf differ
diff --git a/data/chap04.tex b/data/chap04.tex
index 4b75963..abe832f 100644
--- a/data/chap04.tex
+++ b/data/chap04.tex
@@ -116,9 +116,10 @@ FEC解码器按编码组为单位批量恢复和交付数据包。当一个编
\begin{figure}[htbp]
\centering
- \fbox{\parbox{0.85\textwidth}{\centering\small\vspace{1.5em}%
- 图片内容：Pacer控制模型框图。左侧"数据包输入"（来自FEC解码器，标注"突发式到达"）→ 进入"输出缓冲区"（buffer）→ 受控输出paced数据包（标注"匀速输出"）。缓冲区下方有一个"PI控制器"模块，输入为error = depth - target，输出为pacing rate。%
- \vspace{1.5em}}}
+ % \fbox{\parbox{0.85\textwidth}{\centering\small\vspace{1.5em}%
+ % 图片内容：Pacer控制模型框图。左侧"数据包输入"（来自FEC解码器，标注"突发式到达"）→ 进入"输出缓冲区"（buffer）→ 受控输出paced数据包（标注"匀速输出"）。缓冲区下方有一个"PI控制器"模块，输入为error = depth - target，输出为pacing rate。%
+ % \vspace{1.5em}}}
+ \includegraphics[width=\linewidth]{pacer_design.drawio.pdf}
\caption{Pacer控制模型}
\label{fig:pacer控制模型}
\end{figure}
diff --git a/figures/pacer_design.drawio b/figures/pacer_design.drawio
index b025fbc..475726b 100644
--- a/figures/pacer_design.drawio
+++ b/figures/pacer_design.drawio
@@ -1 +1,141 @@
-
\ No newline at end of file
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
diff --git a/figures/pacer_design.drawio.pdf b/figures/pacer_design.drawio.pdf
new file mode 100644
index 0000000..f69aac5
Binary files /dev/null and b/figures/pacer_design.drawio.pdf differ
diff --git a/figures/pacer_design.drawio.svg b/figures/pacer_design.drawio.svg
new file mode 100644
index 0000000..fce3a68
--- /dev/null
+++ b/figures/pacer_design.drawio.svg
@@ -0,0 +1,4 @@
+
+
+
+
\ No newline at end of file