diff --git a/app/algorithms/burst_location/similarity_calculator.py b/app/algorithms/burst_location/similarity_calculator.py
index ff42828..330e88f 100644
--- a/app/algorithms/burst_location/similarity_calculator.py
+++ b/app/algorithms/burst_location/similarity_calculator.py
@@ -583,12 +583,12 @@ def cal_similarity_all_cos_dis(
     monitor_new.iloc[0] = monitor_p
     add_m_leak_pressure = [pressure_leak, monitor_p]
     add_m_leak_pressure = pd.concat(add_m_leak_pressure)
-    pressure_leak_std = np.std(add_m_leak_pressure, ddof=1)
+    pressure_leak_std = add_m_leak_pressure.std(axis=0, ddof=1)
     pressure_leak_std = pd.Series(pressure_leak_std, index=pressure_leak.columns)
 
     add_m_leak_pressure_all = [pressure_leak_all, monitor_p_all]
     add_m_leak_pressure_all = pd.concat(add_m_leak_pressure_all)
-    pressure_leak_std_all = np.std(add_m_leak_pressure_all, ddof=1)
+    pressure_leak_std_all = add_m_leak_pressure_all.std(axis=0, ddof=1)
     pressure_leak_std_all = pd.Series(
         pressure_leak_std_all, index=pressure_leak.columns
     )