subsection

paper/paper.md

@@ -36,7 +36,7 @@ from other seismic networks such as F-net, S-net, V-net, and more. The NIED Hi-n
 renowned for its invaluable contributions to seismological research.
 
 
-# Challenges in accessing NIED Hi-net data
+## Challenges in accessing NIED Hi-net data
 
 To access Hi-net data, users need to register an Hinet account. This registration process
 is necessary to ensure data security and adherence to Hi-net's data usage policies.
@@ -58,7 +58,7 @@ the request, wait for data preparation (which may take a few minutes), and then
 another request. After downloading all the files, we then need to combine these data
 into a single one.
 
-# Challenges in processing NIED Hi-net data
+## Challenges in processing NIED Hi-net data
 
 This format is not widely supported by standard seismology data formats such as miniSEED,
 StationXML, and QuakeML, making it difficult to exchange data with other seismograph