3 Method

Our proposed framework intends to locate insulator areas, determine if these insulators are faulty, and identify which categories these insulators belong to. It needs to be emphasized that the framework explores the feasibility of this task under the conditions that a portion of annotations are inaccessible and sample sizes of various classes are imbalanced. In detail, our framework is based on the Faster RCNN pipeline [27], illustrated in Figure 1. We improved the Faster RCNN by combining PU learning with Region Proposal Network (RPN) and incorporating focal loss into the Region Of Interest (ROI) Head.