Update model_zoo_overview.md

Author: LutaoChu

docs/model_zoo_overview.md

@@ -2,7 +2,7 @@ English | [简体中文](model_zoo_overview_cn.md)
 
 # PaddleSeg model zoo overview
 
-## model zoo
+## Model zoo
 ### CNN Series
 
 |Model\Backbone Network|ResNet50|ResNet101|HRNetw18|HRNetw48|
@@ -79,7 +79,7 @@ Based on the Cityscapes dataset, PaddleSeg supports 22+ series of segmentation a
 <img src=https://user-images.githubusercontent.com/30695251/140323107-02ce9de4-c8f4-4f18-88b2-59bd0055a70b.png //>
 </div>
 
-## Precision vs Params
+## Accuracy vs Params
 <div align="center">
 <img src=https://user-images.githubusercontent.com/30695251/140323131-ed03fbb1-a583-47f5-a7dd-f4ea3582c345.png //>
 </div>