The researchers studied how to mine at a large angle underground while keeping the support stable and recovering coal effectively. They looked at how the support structure needs to be strong to handle the rock around it and reduce accidents. By testing loose particles, they found the best way to mine and collect the coal. They discovered that using a specific mining technique called "upward sequence and double-openings double-rounds" works well for this type of mining. This research will help make mining thick seams at a steep angle safer and more efficient.