I am a Senior AI Researcher at Samsung Research America, where my research focuses on advancing multimodal understanding, editing, and generation for edge devices. My research aims to push the boundaries of AI by optimizing performance in resource-constrained environments.
I earned my PhD in Computer Science from Johns Hopkins University under the supervision of
Bloomberg Distinguished Professor Rama Chellappa.
Prior to that, I completed my Master’s degree at the University of Maryland, College Park.
Throughout my research, I collaborated closely with Tom Goldstein,
Micah Goldblum, and Soheil Feizi at the University of Maryland, as well as Andrew Gordon Wilson
and Yann LeCun from NYU and Meta.
Sept-2024: I joined Samsung Research America as a Senior AI Researcher!
Sept-2024: I successfully defended my PhD dissertation!
July-2024:GDP has been selected for oral presentation at the NextGenAISafety workshop at ICML 2024.
June-2024: One paper accepted to ICML 2024 Workshop on the Next Generation of AI Safety.
Jan-2024: One paper accepted to IEEE ICASSP 2024.
Sept-2023: One paper accepted to NeurIPS 2023.
June-2023: One paper accepted to TPAMI.
May-2023: One papers accepted to AAAI/ACM Conference on AI, Ethics, and Society 2023.
Sept-2022: Two papers accepted to NeurIPS
2022.
July-2022: Three papers accepted to ICML 2022 Workshops.
June-2022: One paper accepted to IEEE TIFS.
Jan-2022: One paper accepted to ICLR 2022.
Nov-2020: One oral paper accepted to IEEE FG 2020 with best paper (Honorable
Mention) award.
Research
My primary research focuses on Multimodal and generative AI.
Previously, I have worked on areas such as adversarial robustness, diffusion models, GANs, vision-language models, object detection and segmentation, as well as data poisoning and backdoor attacks.
In this work, we use guided diffusion
to synthesize base samples from scratch that lead to significantly more potent
poisons and backdoors than previous state-of-the-art attacks. Our Guided Diffusion Poisoning (GDP) base samples can be combined with any downstream
poisoning or backdoor attack to boost its effectiveness.
The adversarial attack literature contains a myriad of algorithms for
crafting perturbations which yield pathological behavior in neural networks.
In many cases, multiple algorithms target the same tasks and even enforce the
same constraints. In this work, we show that different attack algorithms produce
adversarial examples which are distinct not only in their effectiveness but also
in how they qualitatively affect their victims.
Battle of the Backbones (BoB) is a large-scale comparison of pretrained vision backbones
including SSL, vision-language models, and CNNs vs ViTs across diverse downstream tasks
including classification, object detection, segmentation, out-of-distribution (OOD) generalization,
and image retrieval.
In this paper, we propose a novel threat model called
Joint Space Threat Model (JSTM), which can serve as a
special case of the neural perceptual threat model that does
not require additional relaxation to craft the corresponding adversarial attacks.
We also propose Intepolated Joint Space Adversarial Training
(IJSAT), which applies Robust Mixup strategy and trains
the model with JSA samples.
In this paper, we explore the effects of each kind of
imbalance possible in face identification, and discuss other factors which may impact bias in this
setting.
Typical backdoor attacks insert the trigger directly into the training data, although the presence
of such an attack may be visible upon inspection.
We develop a new hidden trigger attack, Sleeper Agent, which employs gradient matching, data
selection, and target model re-training during the crafting process.
Sleeper Agent is the first hidden trigger backdoor attack to be effective against neural networks
trained from scratch.
We demonstrate its effectiveness on ImageNet and in black-box settings.
Our Bayesian transfer learning framework transfers knowledge from pre-training
to downstream tasks. To up-weight parameter settings consistent with a
pre-training loss function, we fit a probability distribution over the
parameters of feature extractors to a pre-training loss function and rescale
it as a prior.
In this paper, we discuss the close relationship between contrastive learning and meta-learning
under a certain task distribution. We complement
this observation by showing that established meta-learning methods,
such as Prototypical Networks, achieve comparable performance to SimCLR
when paired with this task distribution.
In this paper, we propose mutual adversarial training (MAT), in which multiple models are trained
together and share the knowledge of adversarial examples to achieve improved robustness.
MAT allows robust models to explore a larger space of adversarial samples, and
find more robust feature spaces and decision boundaries.
GANs often suffer from the mode collapse issue where the generator fails to capture all existing
modes of the input distribution.
To tackle this issue, we take an information-theoretic approach and maximize a variational lower
bound on the entropy of the generated samples to increase their diversity.
We call this approach GANs with Variational Entropy Regularizers (GAN+VER).
A novel approach called "Adversarial Gender De-biasing (AGD)" to help
mitigate gender bias in face recognition by reducing
the strength of gender information in face recognition features.
In this work we propose a generative single frame restoration algorithm which disentangles the blur
and deformation due to turbulence and reconstructs a restored image.