Li Zhu, Ph.D.

Publications

45+ Publications | 15+ Patents

Google Scholar | Citations: 510 | h-index: 12 | i10-index: 15

Journal Publications

[J1] Atrial Fibrillation Detection and Atrial Fibrillation Burden Estimation via Wearables [Cover Feature]
Li Zhu, V. Nathan, J. Kuang, J. Kim, R. Avram, J. Olgin, J. Gao
IEEE Journal of Biomedical and Health Informatics, 26(5): 2063-2074 (2021) [Paper]
[J2] Validation of an algorithm for continuous monitoring of atrial fibrillation using a consumer smartwatch
R. Avram, M. Ramsis, A. Cristal, V. Nathan, Li Zhu, J. Kim, J. Kuang, A. Gao, et al.
Heart Rhythm 18.9 (2021): 1482-1490 [Paper]
[J3] Towards Early Detection and Burden Estimation of Atrial Fibrillation in an Ambulatory Free-living Environment
H. Zhang, Li Zhu, V. Nathan, J. Kuang, J. Kim, A. Gao, J. Olgin
ACM IMWUT/UbiComp 5.2 (2021): 1-19 [Paper]
[J4] On fractality of functional near-infrared spectroscopy signals: analysis and applications
Li Zhu, S. Haghani, L. Najafizadeh
Neurophotonics 7.2 (2020): 025001 [Paper]
[J5] Decoding Cortical Brain States from Widefield Transcranial Imaging Using Visibility Graph
Li Zhu, C. R. Lee, D. J. Margolis, L. Najafizadeh
Biomedical Optics Express, 9.7 (2018): 3017-3036 [Paper]
[J6] BiCMOS-Based Compensation: Towards Fully Temperature Corrected Bandgap Reference Circuits
Y. Huang, Li Zhu, F. Kong, C. Cheung, L. Najafizadeh
IEEE Trans. on Circuits and Systems-I, 65.4 (2018): 1210-1223 [Paper]
[J7] Dynamic Time Warping-based Averaging Framework for Functional Near-Infrared Spectroscopy Brain Imaging Studies
Li Zhu and L. Najafizadeh
Journal of Biomedical Optics, 22(6): 066011, June 2017 [Paper]

Conference Papers

[C1] Wavelet-Driven Masked Multiscale Reconstruction for PPG Foundation Models
M. Thukral, C. Tanade, S. Lee, J. Lee, H. Zhou, K. S. Chun, M. Gwak, Li Zhu, et al.
arXiv preprint arXiv:2601.12215, 2026 [Paper]
[C2] HiMAE: Hierarchical masked autoencoders discover resolution-specific structure in wearable time series
S. Lee, C. Tanade, H. Zhou, J. Lee, M. Thukral, M. Han, R. Choi, Li Zhu, et al.
arXiv preprint arXiv:2510.25785, 2025 [Paper]
[C3] Towards Cardiac Output Estimation Using Earbud Photoplethysmography Sensor
L. Zhang, M. M. Rahman, M. B. Morshed, Li Zhu, H. Zhou, J. O'Bryan, W. B. Mendes, J. Kuang
IEEE EMBC, 2025
[C4] Precise Opening Detection of Heart Aortic Valve Towards Noninvasive Continuous Blood Pressure Detection
Li Zhu, M. B. Morshed, J.-O. Hahn, M. M. Rahman, S. Desai
IEEE EMBC, 2025
[C5] Optimizing Biomarkers from Earbud Ballistocardiogram: Calibration and Calibration-Free Algorithms
Y. Li, M. M. Rahman, M. B. Morshed, M. S. Islam, H. Zhou, W. Wang, H. Ernst, Li Zhu, J. Kuang
IEEE ICASSP, 2025
[C6] Evaluation of Wearable Head BCG for PTT Measurement in Blood Pressure Intervention
W. Wang, Li Zhu, M. B. Morshed, M. M. Rahman, J. Bae, J. Kuang
IEEE ICASSP, 2025
[C7] Enhance Heart Rate Measurement from Remote PPG with Head Motion Awareness
J. Li, K. Vatanparvar, M. Gwak, Li Zhu, J. Kuang, A. Gao
IEEE EMBC, 2024 [Paper]
[C8] Multimodal breathing rate estimation using facial motion and rPPG from RGB camera
M. Gwak, K. Vatanparvar, Li Zhu, N. Rashid, M. Ahmed, J. Bae, J. Kuang, A. Gao
IEEE ICASSP, 2024 [Paper]
[C9] Freq2time: Weakly supervised learning of camera-based rPPG from heart rate
J. Speth, K. Vatanparvar, Li Zhu, J. Kuang, A. Gao
IEEE ICASSP, 2024 [Paper]
[C10] Heart rate variability estimation with dynamic fine filtering and global-local context outlier removal
R. K. Sah, M. M. Rahman, V. Nathan, Li Zhu, J. Bae, C. Rosa, W. B. Mendes, J. Kuang, A. Gao
IEEE ICASSP, 2024 [Paper]
[C11] Core body temperature and its role in detecting acute stress
M. B. Morshed, M. M. Rahman, V. Nathan, Li Zhu, J. Bae, C. Rosa, W. B. Mendes, J. Kuang, A. Gao
IEEE ICASSP, 2024 [Paper]
[C12] Ballistocardiogram-based heart rate variability estimation for stress monitoring using consumer earbuds
D. J. Lin, M. M. Rahman, Li Zhu, V. Nathan, J. Bae, C. Rosa, W. B. Mendes, J. Kuang, A. Gao
IEEE ICASSP, 2024 [Paper]
[C13] Normalization is all you need: Robust full-range contactless SpO2 estimation across users
Q. Shao, Li Zhu, M. Ahmed, K. Vatanparvar, M. Gwak, N. Rashid, J. Bae, J. Kuang, A. Gao
IEEE ICASSP, 2024 [Paper]
[C14] Advancements in Face Alignment Evaluation for Contact-less Vital Sign Detection
J. Li, R. L. Barmaki, Li Zhu, K. Vatanparvar, M. Gwak, J. Kuang, A. Gao
IEEE BSN, 2023 [Paper]
[C15] Estimating SpO2 with Deep Oxygen Desaturations from Facial Video
M. Chan, Li Zhu, K. Vatanparvar, M. Gwak, J. Kuang, A. Gao
IEEE EMBC, 2023 [Paper]
[C16] Contactless monitoring of respiratory rate and breathing absence from head movements
M. Gwak, K. Vatanparvar, Li Zhu, J. Kuang, A. Gao
IEEE EMBC, 2023 [Paper]
[C17] Enhanced Contactless Heart Rate Monitoring with Motion Artifact Removal
K. Vatanparvar, J. Li, M. Gwak, Li Zhu, J. Kuang, A. Gao
IEEE EMBC, 2023 [Paper]
[C18] Improving heart rate and heart rate variability estimation from video
M. Chan, Li Zhu, K. Vatanparvar, H. Jung, J. Kuang, A. Gao
IEEE ICASSP, 2023 [Paper]
[C19] Respiration rate estimation from remote PPG via camera
K. Vatanparvar, M. Gwak, Li Zhu, J. Kuang, A. Gao
IEEE BSN, 2022 [Paper]
[C20] Enhancement of remote PPG and heart rate estimation with optimal signal quality index
J. Li, K. Vatanparvar, Li Zhu, M. Gwak, J. Kuang, A. Gao
IEEE BSN, 2022 [Paper]
[C21] Contactless SpO2 Detection from Face Using Consumer Camera
Li Zhu, K. Vatanparvar, M. Gwak, J. Kuang, A. Gao
IEEE BSN, 2022 [Paper]
[C22] Remote photoplethysmography and heart rate estimation by dynamic region of interest tracking
W. Wei, K. Vatanparvar, Li Zhu, J. Kuang, A. Gao
IEEE EMBC, 2022 [Paper]
[C23] Device Invariant Deep Neural Networks for Pulmonary Audio Event Detection
M. Ahmed, Li Zhu, M. Rahman, T. Ahmed, J. Kuang, A. Gao
IEEE EMBC, 2021 [Paper]
[C24] Better Battery Life: Towards Energy-Efficient Smartwatch-Based Atrial Fibrillation Detection
H. Zhang, Li Zhu, V. Nathan, J. Kuang, J. Kim, A. Gao
IEEE BSN, 2021 [Paper]
[C25] Photoplethysmography-based blood pressure estimation using deep learning
W. Wang, Li Zhu, F. Marefat, P. Mohseni, K. Kilgore, L. Najafizadeh
54th Asilomar Conference, IEEE, 2020
[C26] Identifying task-related brain functional states via cortical networks
S. Salsabilian, Li Zhu, C. R. Lee, D. J. Margolis, L. Najafizadeh
IEEE ISCAS, 2020
[C27] Identifying Dynamics of Brain Function Via Boolean Matrix Factorization
A. Haddad, F. Shamsi, Li Zhu, L. Najafizadeh
52nd Asilomar Conference, IEEE, 2018
[C28] Spatiotemporal Characterization of Brain Function Via Multiplex Visibility Graph
Li Zhu, S. Haghani, L. Najafizadeh
OSA Technical Digest, Hollywood, FL, 2018
[C29] Probing the Dynamics of Resting-State Cortical Activities via Wide Field Ca+2 Imaging (Invited)
Li Zhu, C. Lee, D. Margolis, L. Najafizadeh
SPIE-Optics and Photonics, 2017
[C30] Predicting Behavior from Cortical Activity Recorded through Widefield Transcranial Imaging
Li Zhu, C. R. Lee, D. J. Margolis, L. Najafizadeh
CLEO, San Jose, CA, 2017
[C31] Assessing Optimal Electrode/Optode Arrangement in EEG-fNIRS Multi-Modal Imaging
Li Zhu, A. Haddad, T. Zeng, Y. Wang, L. Najafizadeh
OSA Technical Digest, Fort Lauderdale, FL, 2016
[C32] Temporal Dynamics of fNIRS-Recorded Signals Revealed Via Visibility Graph
Li Zhu and L. Najafizadeh
OSA Technical Digest, Fort Lauderdale, FL, 2016
[C33] On the Relationship Between Trial-to-Trial Response Time Variability and fNIRS-Based Functional Connectivity
T. Zeng, Li Zhu, Y. Wang, L. Najafizadeh
OSA Technical Digest, Fort Lauderdale, FL, 2016
[C34] Does brain functional connectivity alter across similar trials during imaging experiments?
Li Zhu and L. Najafizadeh
IEEE SPMB, Philadelphia, PA, 2014
[C35] A Low Temperature Coefficient Voltage Reference Utilizing BiCMOS Compensation Technique [Best Paper Runner-Up]
Y. Huang, Li Zhu, C. Cheung, L. Najafizadeh
IEEE ISCAS, Melbourne, 2014
[C36] A Curvature-Compensation Technique Based on the Difference of Si and SiGe Junction Voltages
Y. Huang, Li Zhu, C. Cheung, L. Najafizadeh
IEEE ISCAS, Melbourne, 2014
[C37] Towards Improving the 'Detection' Power of Brain Imaging Experiments Using fNIRS
Li Zhu, M. Peifer, L. Najafizadeh
OSA Technical Digest, Miami, FL, 2014
[C38] Real-time Classification of Finger Tapping vs Imaginary Finger Tapping Using NIRS Data
M. Peifer, Li Zhu, L. Najafizadeh
OSA Technical Digest, Miami, FL, 2014

Patents

Granted Patents

[P1] Multimodal contactless vital sign monitoring
K. Vatanparvar, W. Wei, Li Zhu, M. Gwak, J. Kuang, J. Gao
US Patent 12,414,696, Feb. 2025 [Patent]
[P2] Systems and methods for atrial fibrillation burden estimation, notification and management
V. Nathan, Li Zhu, M. M. Rahman, J. Kuang, J. Gao
US Patent 11,911,165, Feb. 2024 [Patent]
[P3] Non-invasive continuous heart rhythm monitoring based on wearable sensors
Li Zhu, V. Nathan, M. M. Rahman, J. Kuang, J. W. Kim, J. Gao, D. Mortara, J. Olgin
US Patent 11,564,613, Jan. 2023 [Patent]

Patent Applications

[P4] Extracting Biomarkers For Stress Monitoring Using Mobile Devices
Li Zhu, M. M. Rahman, V. Nathan, J. Kuang, A. Gao
US Patent App. 18/824,767 (2025)
[P5] Adaptable Camera-based Contactless SpO2 Detection
Li Zhu, M. Chan, K. Vatanparvar, J. Kuang, A. Gao
US Patent App. 18/759,674 (2025)
[P6] Enhanced vision-based vitals monitoring using multi-modal soft labels
Li Zhu, K. Vatanparvar, M. Gwak, J. Kuang, A. Gao
US Patent App. 18/814,096 (2025)
[P7] Face Alignment and Normalization For Enhanced Vision-Based Vitals Monitoring
K. Vatanparvar, J. Speth, J. Li, Li Zhu, N. Rashid, M. Gwak, J. Kuang, J. Gao
US Patent App. 18/677,228 (2024)
[P8] Contactless monitoring of respiratory rate and breathing absence using face video
Li Zhu, M. Gwak, K. Vatanparvar, J. Kuang, A. Gao
US Patent App. 18/432,599 (2024)
[P9] Determining Oxygen Levels From Images of Skin
Li Zhu, M. Chan, K. Vatanparvar, J. Kuang, A. Gao
US Patent App. 18/213,461 (2024)
[P10] Camera-Based Contactless Monitoring of Physiological Parameters
Li Zhu, K. Vatanparvar, M. Gwak, J. Kuang, A. Gao
US Patent App. 18/222,118 (2024)
[P11] Systems and methods to detect and characterize stress using physiological sensors
Li Zhu, M. M. Rahman, V. Nathan, J. Kuang, A. Gao
US Patent App. 18/156,292 (2023)
[P12] Energy efficient detection and management of atrial fibrillation
Li Zhu, V. Nathan, J. Kuang, J. Kim, A. Gao
US Patent App. 17/564,198 (2022)
[P13] Device-invariant, frequency-domain signal processing with machine learning
Li Zhu, M. Ahmed, J. Kuang, A. Gao
US Patent App. 17/245,951 (2022)
[P14] Wearable device for non-invasive continuous blood pressure monitoring
Li Zhu, W. Wang, L. Najafizadeh, P. Mohseni
US Patent App. 16/164,777 (2018)

Ph.D. Dissertation

Computational Methods for Predicting Behavior from Neuroimaging Data
Li Zhu
Ph.D. Dissertation, Rutgers University, 2018