diff --git a/brep2sdf/networks/network.py b/brep2sdf/networks/network.py
index 0d82a43..babdddb 100644
--- a/brep2sdf/networks/network.py
+++ b/brep2sdf/networks/network.py
@@ -101,11 +101,11 @@ class Net(nn.Module):
 
         # 对 operator == 0 的样本取最大值
         if mask_concave.any():
-            output[mask_concave] = torch.max(padded_f_i[mask_concave], dim=1).values
+            output[mask_concave] = torch.min(padded_f_i[mask_concave], dim=1).values
 
         # 对 operator == 1 的样本取最小值
         if mask_convex.any():
-            output[mask_convex] = torch.min(padded_f_i[mask_convex], dim=1).values
+            output[mask_convex] = torch.max(padded_f_i[mask_convex], dim=1).values
 
         #logger.gpu_memory_stats("combine后")
         return output
@@ -187,6 +187,19 @@ class Net(nn.Module):
         return f_i.squeeze()
 
 
+    def freeze_stage1(self):
+        self.encoder.freeze_stage1()
+
+    def freeze_stage2(self):
+        self.encoder.freeze_stage2()
+        for param in self.decoder.parameters():
+            param.requires_grad = False
+
+    def unfreeze(self):
+        self.encoder.unfreeze()
+        for param in self.decoder.parameters():
+            param.requires_grad = True
+