Learn2Perturb: an End-to-end Feature Perturbation Learning to Improve Adversarial Robustness

TL;DR

Learn2Perturb enhances adversarial robustness through end-to-end feature perturbation learning, achieving 4-7% improvement on CIFAR-10.

cs.CV 🔴 Advanced 2020-03-03 33 views
Ahmadreza Jeddi Mohammad Javad Shafiee Michelle Karg Christian Scharfenberger Alexander Wong
adversarial attacks deep learning robustness feature perturbation machine learning

Key Findings

Methodology

Learn2Perturb introduces perturbation-injection modules at each layer to perturb the feature space and increase network uncertainty. An alternating back-propagation algorithm inspired by Expectation-Maximization is used to train network and noise parameters iteratively.

Key Results

  • On CIFAR-10 and CIFAR-100 datasets, Learn2Perturb improves deep neural networks' robustness by 4-7% against l∞ FGSM and PDG adversarial attacks.
  • Significantly outperforms state-of-the-art methods against l2 C&W attack and various black-box attacks.
  • Ablation studies confirm the effectiveness of perturbation-injection modules.

Significance

This study significantly enhances the adversarial robustness of deep neural networks by introducing dynamic feature perturbations, addressing the limitations of fixed perturbation methods, and providing more reliable solutions for safety-critical applications.

Technical Contribution

Introduces a novel end-to-end feature perturbation learning framework combined with an alternating back-propagation strategy, effectively enhancing network adversarial robustness, surpassing existing random noise injection techniques.

Novelty

First to introduce feature perturbation modules during both training and inference, dynamically adjusting noise distributions to enhance robustness, offering significant innovation over traditional fixed perturbation methods.

Limitations

  • Performance on high-dimensional datasets remains unverified, potentially posing scalability issues.
  • Further optimization of noise parameter convergence is needed.

Future Work

Future research could explore applications on larger-scale datasets and optimize the dynamic adjustment mechanism for noise parameters.

AI Executive Summary

Deep neural networks excel in many applications, but their vulnerability to adversarial attacks limits their deployment in safety-critical areas. Existing methods often rely on fixed perturbations, making them hard to generalize.

Learn2Perturb enhances adversarial robustness through end-to-end feature perturbation learning. It introduces novel perturbation-injection modules at each layer to increase network uncertainty. An alternating back-propagation algorithm inspired by Expectation-Maximization is used to iteratively train network and noise parameters.

Experimental results show that Learn2Perturb significantly improves adversarial robustness on CIFAR-10 and CIFAR-100 datasets, especially achieving a 4-7% improvement against l∞ FGSM and PDG attacks. The method also excels in l2 C&W and various black-box attacks, offering new possibilities for enhancing the security of deep neural networks.

Deep Analysis

Background

Deep neural networks have made significant advances in image recognition, natural language processing, and more. However, their vulnerability to adversarial attacks poses a barrier to widespread application. Adversarial attacks subtly alter inputs to cause incorrect model outputs. Existing defenses like adversarial training and feature denoising, while effective, have limitations.

Core Problem

Deep neural networks are susceptible to adversarial attacks, especially in safety-critical applications. Existing methods often rely on fixed perturbations, requiring extensive hyperparameter tuning, making them hard to generalize.

Innovation

Learn2Perturb introduces dynamic perturbation-injection modules at each layer to increase network uncertainty. It employs an alternating back-propagation strategy inspired by Expectation-Maximization to iteratively optimize network and noise parameters.

Methodology

  • �� Introduce perturbation-injection modules at each layer to perturb feature space.
  • �� Use an alternating back-propagation algorithm inspired by Expectation-Maximization.
  • �� Apply perturbations during both training and inference.
  • �� Combine with PGD adversarial training to enhance robustness.

Experiments

Experiments conducted on CIFAR-10 and CIFAR-100 datasets, with baselines including PGD adversarial training models. Evaluation metrics include robustness against l∞ FGSM, PDG, and l2 C&W attacks. Ablation studies verify module effectiveness.

Results

Learn2Perturb improves robustness by 4-7% against l∞ FGSM and PDG attacks on CIFAR-10 and CIFAR-100 datasets. It excels in l2 C&W attacks, significantly outperforming state-of-the-art methods.

Applications

The method can enhance the robustness of deep neural networks in safety-critical applications, such as autonomous driving and medical diagnostics.

Limitations & Outlook

Current method's performance on high-dimensional datasets remains unverified, potentially posing scalability issues. Noise parameter convergence needs further optimization.

Plain Language Accessible to non-experts

Imagine a factory where machines process different materials. Some materials have defects, causing machines to make errors. Learn2Perturb acts like a smart sensor on each machine, detecting material changes in real-time and adjusting machine operations accordingly. This dynamic adjustment allows the factory to operate smoothly even with defective materials, improving overall efficiency.

ELI14 Explained like you're 14

Imagine playing a game where enemies constantly try to find your weaknesses. Learn2Perturb is like equipping your character with smart armor that senses attacks and automatically adjusts defense strategies. This makes you harder to beat in the game, keeping you ahead!

Glossary

Adversarial Attack

An adversarial attack subtly alters inputs to cause incorrect model outputs.

Used in the study to test model robustness.

Perturbation Injection Module

A component introduced in network layers to perturb the feature space.

Introduced at each layer to increase network uncertainty.

Alternating Back-Propagation

A training strategy that alternately optimizes network and noise parameters.

Used to iteratively optimize the Learn2Perturb framework.

Expectation-Maximization

A statistical method for finding maximum likelihood estimates in models with latent variables.

Inspiration for the alternating back-propagation algorithm.

CIFAR-10

A commonly used image classification dataset with 10 classes of natural images.

Used to evaluate Learn2Perturb's robustness.

Open Questions Unanswered questions from this research

  • 1 How to verify Learn2Perturb's effectiveness on high-dimensional datasets? Current methods may face scalability issues.
  • 2 How to optimize the dynamic adjustment mechanism for noise parameters to improve convergence?

Applications

Immediate Applications

Autonomous Driving

Enhance the robustness of autonomous driving systems against environmental changes, reducing security risks from adversarial attacks.

Long-term Vision

Medical Diagnostics

Enhance the robustness of medical diagnostic systems, ensuring accurate diagnoses even under adversarial attacks.

Abstract

While deep neural networks have been achieving state-of-the-art performance across a wide variety of applications, their vulnerability to adversarial attacks limits their widespread deployment for safety-critical applications. Alongside other adversarial defense approaches being investigated, there has been a very recent interest in improving adversarial robustness in deep neural networks through the introduction of perturbations during the training process. However, such methods leverage fixed, pre-defined perturbations and require significant hyper-parameter tuning that makes them very difficult to leverage in a general fashion. In this study, we introduce Learn2Perturb, an end-to-end feature perturbation learning approach for improving the adversarial robustness of deep neural networks. More specifically, we introduce novel perturbation-injection modules that are incorporated at each layer to perturb the feature space and increase uncertainty in the network. This feature perturbation is performed at both the training and the inference stages. Furthermore, inspired by the Expectation-Maximization, an alternating back-propagation training algorithm is introduced to train the network and noise parameters consecutively. Experimental results on CIFAR-10 and CIFAR-100 datasets show that the proposed Learn2Perturb method can result in deep neural networks which are $4-7\%$ more robust on $l_{\infty}$ FGSM and PDG adversarial attacks and significantly outperforms the state-of-the-art against $l_2$ $C\&W$ attack and a wide range of well-known black-box attacks.

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