Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: You Only Propagate Once: Accelerating Adversarial Training via Maximal
  Principle   Deep learning achieves state-of-the-art results in many tasks in computer
vision and natural language processing. However, recent works have shown that
deep networks can be vulnerable to adversarial perturbations, which raised a
serious robustness issue of deep networks. Adversarial training, typically
formulated as a robust optimization problem, is an effective way of improving
the robustness of deep networks. A major drawback of existing adversarial
training algorithms is the computational overhead of the generation of
adversarial examples, typically far greater than that of the network training.
This leads to the unbearable overall computational cost of adversarial
training. In this paper, we show that adversarial training can be cast as a
discrete time differential game. Through analyzing the Pontryagin's Maximal
Principle (PMP) of the problem, we observe that the adversary update is only
coupled with the parameters of the first layer of the network. This inspires us
to restrict most of the forward and back propagation within the first layer of
the network during adversary updates. This effectively reduces the total number
of full forward and backward propagation to only one for each group of
adversary updates. Therefore, we refer to this algorithm YOPO (You Only
Propagate Once). Numerical experiments demonstrate that YOPO can achieve
comparable defense accuracy with approximately 1/5 ~ 1/4 GPU time of the
projected gradient descent (PGD) algorithm. Our codes are available at
https://https://github.com/a1600012888/YOPO-You-Only-Propagate-Once.

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The categories of this paper are: alg-geom
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The categories of this paper are: comp-gas
35
The categories of this paper are: mtrl-th
15
The categories of this paper are: nucl-ex
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The categories of this paper are: chem-ph
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The categories of this paper are: solv-int
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The categories of this paper are: hep-lat
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The categories of this paper are: hep-ex
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The categories of this paper are: eess
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The categories of this paper are: quant-ph
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The categories of this paper are: patt-sol
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The categories of this paper are: astro-ph
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The categories of this paper are: nlin
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The categories of this paper are: q-bio
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The categories of this paper are: q-fin
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The categories of this paper are: q-alg