DEEP RESIDUAL LEARNING FOR IMAGE RECOGNITION
KAIMINGHE, XIANGYUZHANG
SHAOQINGREN, JIANSUN
MICROSOFT RESEARCH
2017-08-17
신윤호
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KAIMINGHE
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CONTENTS
Motivation
Related Work
Deep Residual Learning
Experiments
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MOTIVATION
Network depth is of crucial importance,
but it is difficultto train deep neural networks
•There are vanishing/exploding gradients problems
•When deeper networks are able to start converging, a degradationproblem
has been exposed(not caused by overfitting)
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MOTIVATION
Proposed network address the degradationproblem by introducing a
‘deep residual learning’ framework
They show
1.A simple and clean framework of training ‘very’ deep nets
2.State-of-the-art performance for Image classification/Object
detection/Semantic segmentation/and more…
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RELATED WORK
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DEEP RESIDUAL LEARNING
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DEEP RESIDUAL LEARNING
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DEEP RESIDUAL LEARNING
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DEEP RESIDUAL LEARNINGxWxFy
i
}){,(
If identity mappings are optimal, the solvers drive the weights of
nonlinear layers toward zero
So if the optimal function is closer to an identity mapping, it
should be easier for the solver to find the perturbations
The shortcut connections introduce neither extra parameter nor
computation complexity
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DEEP RESIDUAL LEARNING
Network Architectures
•It is worth that this model
has fewer filters and lower
complexitythan VGG nets
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DEEP BOTTLENECK ARCHITECTURES
1 x 1 layers are responsible for reducing and then increasing
dimensions, leaving the 3 x 3 layer with smaller input/output
dimensions
Using this, the number of layers increases and enjoy significant
accuracy gains from increased depth
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EXPERIMENTS
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EXPERIMENT
Deeper layers don’t always work. Due to overfitting, the accuracy
rate at 1202 layers is lower than at 110 layers
ResNetshows good generalization performance on Object
Detection also