diff --git a/mcdc/src/surface/plane.py b/mcdc/src/surface/plane.py
index b4c5048b..19fdf94b 100644
--- a/mcdc/src/surface/plane.py
+++ b/mcdc/src/surface/plane.py
@@ -58,9 +58,9 @@ def _evaluate_moving(particle, surface):
     idx = common._get_move_idx(particle["t"], surface)
 
     # Translation velocity
-    Vx = surface["move_velocities"][idx][0]
-    Vy = surface["move_velocities"][idx][1]
-    Vz = surface["move_velocities"][idx][2]
+    Vx = surface["move_velocities"][idx, 0]
+    Vy = surface["move_velocities"][idx, 1]
+    Vz = surface["move_velocities"][idx, 2]
 
     # Translated position
     t_local = particle["t"] - surface["move_time_grid"][idx]
@@ -134,9 +134,9 @@ def _get_normal_component_moving(particle, speed, surface):
     idx = common._get_move_idx(particle["t"], surface)
 
     # Translation velocity
-    Vx = surface["move_velocities"][idx][0]
-    Vy = surface["move_velocities"][idx][1]
-    Vz = surface["move_velocities"][idx][2]
+    Vx = surface["move_velocities"][idx, 0]
+    Vy = surface["move_velocities"][idx, 1]
+    Vz = surface["move_velocities"][idx, 2]
 
     # Relative direction
     rVx = particle["ux"] - Vx / speed
@@ -198,9 +198,9 @@ def _get_distance_moving(particle, speed, surface):
     # Evaluate the current and the subsequent intervals until intersecting
     while idx < surface["N_move"]:
         # Apply translation velocity
-        Vx = surface["move_velocities"][idx][0]
-        Vy = surface["move_velocities"][idx][1]
-        Vz = surface["move_velocities"][idx][2]
+        Vx = surface["move_velocities"][idx, 0]
+        Vy = surface["move_velocities"][idx, 1]
+        Vz = surface["move_velocities"][idx, 2]
         particle["ux"] -= Vx / speed
         particle["uy"] -= Vy / speed
         particle["uz"] -= Vz / speed
diff --git a/mcdc/src/surface/plane_x.py b/mcdc/src/surface/plane_x.py
index f7d5f1c0..f9a1ace1 100644
--- a/mcdc/src/surface/plane_x.py
+++ b/mcdc/src/surface/plane_x.py
@@ -37,7 +37,7 @@ def _evaluate_moving(particle, surface):
     idx = common._get_move_idx(particle["t"], surface)
 
     # Translation velocity
-    Vx = surface["move_velocities"][idx][0]
+    Vx = surface["move_velocities"][idx, 0]
 
     # Translated position
     t_local = particle["t"] - surface["move_time_grid"][idx]
@@ -80,7 +80,7 @@ def _get_normal_component_moving(particle, speed, surface):
     idx = common._get_move_idx(particle["t"], surface)
 
     # Translation velocity
-    Vx = surface["move_velocities"][idx][0]
+    Vx = surface["move_velocities"][idx, 0]
 
     # Return relative direction
     return particle["ux"] - Vx / speed
@@ -134,7 +134,7 @@ def _get_distance_moving(particle, speed, surface):
     # Evaluate the current and the subsequent intervals until intersecting
     while idx < surface["N_move"]:
         # Apply translation velocity
-        Vx = surface["move_velocities"][idx][0]
+        Vx = surface["move_velocities"][idx, 0]
         particle["ux"] -= Vx / speed
 
         # Get distance
diff --git a/mcdc/src/surface/plane_y.py b/mcdc/src/surface/plane_y.py
index 9dbfec44..6aebe589 100644
--- a/mcdc/src/surface/plane_y.py
+++ b/mcdc/src/surface/plane_y.py
@@ -37,7 +37,7 @@ def _evaluate_moving(particle, surface):
     idx = common._get_move_idx(particle["t"], surface)
 
     # Translation velocity
-    Vy = surface["move_velocities"][idx][1]
+    Vy = surface["move_velocities"][idx, 1]
 
     # Translated position
     t_local = particle["t"] - surface["move_time_grid"][idx]
@@ -80,7 +80,7 @@ def _get_normal_component_moving(particle, speed, surface):
     idx = common._get_move_idx(particle["t"], surface)
 
     # Translation velocity
-    Vy = surface["move_velocities"][idx][1]
+    Vy = surface["move_velocities"][idx, 1]
 
     # Return relative direction
     return particle["uy"] - Vy / speed
@@ -134,7 +134,7 @@ def _get_distance_moving(particle, speed, surface):
     # Evaluate the current and the subsequent intervals until intersecting
     while idx < surface["N_move"]:
         # Apply translation velocity
-        Vy = surface["move_velocities"][idx][1]
+        Vy = surface["move_velocities"][idx, 1]
         particle["uy"] -= Vy / speed
 
         # Get distance
diff --git a/mcdc/src/surface/plane_z.py b/mcdc/src/surface/plane_z.py
index c1cc7216..bcede79b 100644
--- a/mcdc/src/surface/plane_z.py
+++ b/mcdc/src/surface/plane_z.py
@@ -37,7 +37,7 @@ def _evaluate_moving(particle, surface):
     idx = common._get_move_idx(particle["t"], surface)
 
     # Translation velocity
-    Vz = surface["move_velocities"][idx][2]
+    Vz = surface["move_velocities"][idx, 2]
 
     # Translated position
     t_local = particle["t"] - surface["move_time_grid"][idx]
@@ -80,7 +80,7 @@ def _get_normal_component_moving(particle, speed, surface):
     idx = common._get_move_idx(particle["t"], surface)
 
     # Translation velocity
-    Vz = surface["move_velocities"][idx][2]
+    Vz = surface["move_velocities"][idx, 2]
 
     # Return relative direction
     return particle["uz"] - Vz / speed
@@ -134,7 +134,7 @@ def _get_distance_moving(particle, speed, surface):
     # Evaluate the current and the subsequent intervals until intersecting
     while idx < surface["N_move"]:
         # Apply translation velocity
-        Vz = surface["move_velocities"][idx][2]
+        Vz = surface["move_velocities"][idx, 2]
         particle["uz"] -= Vz / speed
 
         # Get distance