Update object_detection.md

docs/train/object_detection.md

@@ -12,7 +12,7 @@ PaddleX目前提供了FasterRCNN和YOLOv3两种检测结构，多种backbone模
 | :----------------  | :------- | :------- | :---------  | :---------  | :-----    |
 | [YOLOv3-MobileNetV1](https://github.com/PaddlePaddle/PaddleX/blob/develop/tutorials/train/object_detection/yolov3_mobilenetv1.py) |  29.3%  |  99.2MB  |  15.442ms   | -  |  模型小，预测速度快，适用于低性能或移动端设备   |
 | [YOLOv3-MobileNetV3](https://github.com/PaddlePaddle/PaddleX/blob/develop/tutorials/train/object_detection/yolov3_mobilenetv3.py)        | 31.6%  | 100.7MB   |  143.322ms  | -  |  模型小，移动端上预测速度有优势   |
-| [YOLOv3-DarkNet53](https://github.com/PaddlePaddle/PaddleX/blob/develop/tutorials/train/object_detection/yolov3_darknet53.py)     | 38.9  | 249.2MB   | 42.672ms   | -  |  模型较大，预测速度快，适用于服务端   |
+| [YOLOv3-DarkNet53](https://github.com/PaddlePaddle/PaddleX/blob/develop/tutorials/train/object_detection/yolov3_darknet53.py)     | 38.9%  | 249.2MB   | 42.672ms   | -  |  模型较大，预测速度快，适用于服务端   |
 | [FasterRCNN-ResNet50-FPN](https://github.com/PaddlePaddle/PaddleX/blob/develop/tutorials/train/object_detection/faster_rcnn_r50_fpn.py)   |  37.2%   |   167.7MB    |  197.715ms       |   -    | 模型精度高，适用于服务端部署   |
 | [FasterRCNN-ResNet18-FPN](https://github.com/PaddlePaddle/PaddleX/blob/develop/tutorials/train/object_detection/faster_rcnn_r18_fpn.py)   |  32.6%   |   173.2MB    |  -       |   -    | 模型精度高，适用于服务端部署   |
 | [FasterRCNN-HRNet-FPN](https://github.com/PaddlePaddle/PaddleX/blob/develop/tutorials/train/object_detection/faster_rcnn_hrnet_fpn.py)   |  36.0%   |   115.MB    |  81.592ms       |   -    | 模型精度高，预测速度快，适用于服务端部署   |