Dynamically activate Dataset, including multiple modeltarget and image

Hi,

    Situation is like this, my program include the dataset of image recognition and two modeltarget,The image-recognition dataset contains nine images,I dynamic activation was a success, no error, and can identify, but sometimes to activate a picture recognition occurs for a long time before, or simply cannot identify exit again into sometimes able to identify, I don't know what are the reasons for this to happen?

    The attachment is the code I loaded dynamically. I loaded it dynamically in a scene. When I quit identification, I will call DeactivateDateset.