We present a probabilistic framework for studying adversarial attacks on discrete data. Based on this framework, we derive a perturbation-based method, Greedy Attack, and a scalable learning-based method, Gumbel Attack, that illustrate various tradeoffs in the design of attacks. We demonstrate the effectiveness of these methods using both quantitative metrics and human evaluation on various stateof-the-art models for text classification, including a word-based CNN, a character-based CNN and an LSTM. As an example of our results, we show that the accuracy of character-based convolutional networks drops to the level of random selection by modifying only five characters through Greedy Attack.
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Photonic Crystal Enhanced Fluorescence with DNA-based Nano-gripper for Ultrasensitive SARS-CoV-2 Biosensing
DNA-origami based nano-grippers, integrated with aptamer-based nanoswitches, generate fluorescent signals when detecting SARS-CoV-2. The integration of Photonic Crystal Enhanced Fluorescence Microscope enables a 104-fold enhancement compared to a single fluorophore reporter on glass substrate, providing a promising tool for ultrasensitive detection and rapid diagnostics.
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- Award ID(s):
- 1900277
- PAR ID:
- 10532048
- Publisher / Repository:
- IEEE Photonics Conference
- Date Published:
- Format(s):
- Medium: X
- Location:
- Orlando, FL
- Sponsoring Org:
- National Science Foundation
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