Internal change

PiperOrigin-RevId: 348063144

official/vision/beta/configs/experiments/video_classification/k400_3d-resnet50_tpu.yaml

 # 3D ResNet-50 video classification on Kinetics-400. 75.3% top-1 and 91.2% top-5 accuracy.
+#
+# --experiment_type=video_classification_kinetics400
+# Expected accuracy on TPU 8x8: 75.1%
+# Updated: 2020-12-16
 runtime:
   distribution_strategy: 'tpu'
   mixed_precision_dtype: 'bfloat16'
 task:
   model:
+    dropout_rate: 0.5
+    norm_activation:
+      use_sync_bn: false
     backbone:
       resnet_3d:
         block_specs: !!python/tuple
@@ -39,7 +46,6 @@ task:
         stem_conv_temporal_kernel_size: 5
         stem_conv_temporal_stride: 2
         stem_pool_temporal_stride: 2
-    dropout_rate: 0.5
   train_data:
     name: kinetics400
     global_batch_size: 1024
@@ -55,11 +61,11 @@ trainer:
     learning_rate:
       cosine:
         initial_learning_rate: 0.8
-        decay_steps: 42104
+        decay_steps: 42000
     warmup:
       linear:
-        warmup_steps: 1053
-  train_steps: 42104
+        warmup_steps: 1050
+  train_steps: 42000
   steps_per_loop: 500
   summary_interval: 500
   validation_interval: 500