<p>This is called "Squeeze-and-Excitation" or "SE" block (see the <a href="https://arxiv.org/pdf/1709.01507.pdf" rel="nofollow noreferrer">paper</a> by Hu et. al). The target of this block is to weight the channels of the previous layer, based on some "global" understanding of each channel's importance and dependencies between channels. See the following figure (from the paper):</p>

<p><a href="https://i.stack.imgur.com/df63P.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/df63P.png" alt="figure 1 from the &quot;Squeeze-and-Excitation&quot; paper"></a></p>

<p>and in details, the difference between residual connection and "SE" connection is (again, figure from the paper):</p>

<p><a href="https://i.stack.imgur.com/6uGDc.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/6uGDc.png" alt="figure 3 from the &quot;Squeeze-and-Excitation&quot; paper"></a></p>

<p>Specifically in the grpah you sent, it seems that they use 1x1 pointwize convolutions instead of a fully-connected layers, but the idea is similar.</p>
What is this kind of mapping reffered as?
<p>I know about the residual mapping proposed by <a href="https://arxiv.org/pdf/1512.03385.pdf" rel="nofollow noreferrer">He et al.</a> But recently I came across this kind of mapping in the EfficientNetB0 architecture, 
<a href="https://i.stack.imgur.com/h5NDO.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/h5NDO.png" alt="enter image description here"></a></p>

<p>The residual units add the previous mapping to the processed block, but here they're multiplying. Could someone explain the significance of this operation and what this mapping is called? Can you link a few papers which describe this?</p>