The core task of object detection is to extract features of various sizes by hierarchically stacking multi-scale feature maps. However. it is not easy to decide whether we should transmit semantic information to the low layers while reducing the loss of semantic information of the high-level features. In this paper. https://www.bekindtopets.com/flash-grab-Viqua-F4-Ultraviolet-Water-System-Powered-by-UVMax-36-gpm-top-savings/