Contact Bio Areas Education Employment Memberships Awards & Honors Publications Talks Patents Funding Teaching Mentoring Service
Panagiotis Markopoulos, Ph.D.

Dr. Panagiotis Markopoulos

Associate Professor & Cloud Technology Endowed Fellow
Departments of Computer Engineering and Computer Science
College of AI, Cyber and Computing
The University of Texas at San Antonio

Contact

Brief Biography

Dr. Panagiotis (Panos) Markopoulos is an Associate Professor and Cloud Technology Endowed Fellow in the Departments of Computer Engineering and Computer Science at The University of Texas at San Antonio. He is the Founding Director of the Machine Learning Optimization and Systems (MILOS) Laboratory and serves as Thrust Lead for Trustworthy AI in The UTSA AI Consortium for Human Well-Being (MATRIX). His research interests include machine learning, signal processing, computer vision, remote sensing, wireless communications, quantum computing, numerical/stochastic optimization, and multilinear algebra, all with emphasis on solutions for high-stakes and resource-constrained applications in defense, healthcare, cybersecurity, and networked autonomous systems. He has authored more than 95 peer-reviewed journal and conference papers and has received research funding from the National Science Foundation, the Air Force Office of Scientific Research, the National Geospatial-Intelligence Agency, and other agencies. Dr. Markopoulos is a recipient of the AFOSR Young Investigator Program Award. He is an IEEE Senior Member and a member of SPIE and ASEE. He has been elected a member of IEEE-Eta Kappa Nu (IEEE-HKN), the Honor Society of IEEE, and Sigma Xi, The Scientific Research Honor Society. He received the Ph.D. degree in electrical engineering from the University at Buffalo in 2015 and the Diploma and M.Sc. degrees, both in Electronic and Computer Engineering, from the Technical University of Crete, Greece, in 2010 and 2012, respectively.

Research Areas

Technical Domains

Selected Application Domains

Education

Employment

Memberships

Professional Society Memberships

Honor Society Memberships (Elected)

Awards & Honors

Professional Honors and Major Awards

Paper Awards

Selected Advisee Distinctions

Publications

Publication metrics (as of June 10, 2026):

Journal Articles (Refereed)
Advisees are marked with (^\dag).

  1. P. Markopoulos, “Continual Learning in Cybersecurity: Failure Modes and a Case for Managed Adaptation,” IEEE Aerosp. Electron. Syst. Mag., submitted June. 2026. Under review.

  2. R. U. Haque^\dag, W.-M. Lin, and P. Markopoulos, “Federated Learning for Branch Prediction,” IEEE Trans. Comput., submitted Apr. 2026. Under review.

  3. R. U. Haque^\dag and P. Markopoulos, “FedAlign: Robust Federated Learning via Peer-Consensus Alignment,” IEEE Trans. Neural Net. Learn. Syst, submitted Jan. 2026. Under review.

  4. V. T. Nguyen^\dag and P. Markopoulos, “Quantum Adaptive Low-Rank CP Decomposition,” IEEE Trans. Quantum Eng., submitted Mar. 2026. Under review.

  5. M. Dhanaraj^\dag, V. T. Nguyen^\dag, and P. Markopoulos, “Adaptive Low-Rank Multilinear Transformations for Compact Convolutional Neural Networks,” IEEE Trans. Artif. Intell., submitted Jan. 2026. Under review.

  6. I. Tomeo^\dag, P. Markopoulos, and A. Savakis, “Quantum Annealing for Robust Principal Component Analysis,” IEEE Trans. Quantum Eng., pp. 1–11, Feb. 2026.
    DOI: 10.1109/TQE.2026.3661822

  7. R. U. Haque^\dag and P. Markopoulos, “Federated Learning With Automated Dual-Level Hyperparameter Tuning,” IEEE Open J. Signal Process., vol. 6, pp. 795–802, June 2025.
    DOI: 10.1109/OJSP.2025.3578273

  8. M. Sharma^\dag, J. Heard, E. Saber, and P. Markopoulos, “Convolutional Neural Network Compression via Dynamic Parameter Rank Pruning,” IEEE Access, vol. 13, pp. 18441–18456, 2025.
    DOI: 10.1109/ACCESS.2025.3533419

  9. S. Singh, E. Saber, P. Markopoulos, and J. Heard, “Regulating Modality Utilization within Multimodal Fusion Networks,” Sensors, vol. 24, no. 6054, Sept. 2024.
    DOI: 10.3390/s24186054

  10. S. Colonnese, G. Scarano, M. Marra, P. Markopoulos, and D. A. Pados, “Joint Analysis and Segmentation of Time-varying Data with Outliers,” Digital Signal Processing (Elsevier), vol. 145, no. 104338, Feb. 2024.
    DOI: 10.1016/j.dsp.2023.104338

  11. M. Dhanaraj^\dag and P. Markopoulos, “On the Asymptotic L1-PC of Elliptical Distributions,” IEEE Signal Process. Lett., vol. 29, pp. 2343–2347, Sept. 2022.
    DOI: 10.1109/LSP.2022.3205274

  12. S. Colonnese, P. Markopoulos, G. Scarano, and D. A. Pados, “FFT Calculation of the L1-norm Principal Component of a Data Matrix,” Signal Processing (Elsevier), vol. 189, no. 108286, Aug. 2021.
    DOI: 10.1016/j.sigpro.2021.108286

  13. D. G. Chachlakis^\dag, T. Zhou, F. Ahmad, and P. Markopoulos, “Minimum Mean-Squared-Error Autocorrelation Processing in Coprime Arrays,” Digital Signal Processing (Elsevier), vol. 114, no. 103034, July 2021.
    DOI: 10.1016/j.dsp.2021.103034

  14. D. G. Chachlakis^\dag, M. Dhanaraj^\dag, A. Prater-Bennette, and P. Markopoulos, “Dynamic L1-norm Tucker Tensor Decomposition,” IEEE J. Sel. Topics Signal Process., vol. 15, no. 3, pp. 587–602, Apr. 2021.
    DOI: 10.1109/JSTSP.2021.3058846

  15. D. G. Chachlakis^\dag and P. Markopoulos, “Structured Autocorrelation Matrix Estimation for Coprime Arrays,” Signal Processing (Elsevier), vol. 183, no. 107987, June 2021.
    DOI: 10.1016/j.sigpro.2021.107987

  16. M. Sharma^\dag, M. Dhanaraj^\dag, D. G. Chachlakis^\dag, S. Karam, R. Ptucha, P. Markopoulos, and E. Saber, “YOLOrs: Object Detection in Multimodal Remote Sensing Imagery,” IEEE J. Sel. Topics Appl. Earth Obs. Remote Sens., vol. 14, pp. 1497–1508, Nov. 2021.
    DOI: 10.1109/JSTARS.2020.3041316

  17. H. Kamrani, A. Zoghadr Asli, P. Markopoulos, M. Langberg, D. A. Pados, and G. N. Karystinos, “Reduced-Rank L1-Norm Principal-Component Analysis with Performance Guarantees,” IEEE Trans. Signal Process., vol. 69, pp. 240–255, Nov. 2020.
    DOI: 10.1109/TSP.2020.3039599

  18. S. A. Mamun, A. Ganguly, P. Markopoulos, M. Kwon, and A. Kwasinski, “NASCon: Network-Aware Server Consolidation for Server-Centric Wireless Datacenters,” Sustainable Computing: Informatics and Systems (Elsevier), vol. 29 (part A), no. 100452, Mar. 2021.
    DOI: 10.1016/j.suscom.2020.100452

  19. D. G. Chachlakis^\dag, P. Markopoulos, and A. Prater-Bennette, “L1-Norm Tucker Tensor Decomposition,” IEEE Access, vol. 7, pp. 178454–178465, Nov. 2019.
    DOI: 10.1109/ACCESS.2019.2955134

  20. Y. Liang, P. Markopoulos, and E. Saber, “Spatial-Spectral Segmentation of Hyperspectral Images for Subpixel Target Detection,” J. Appl. Remote Sens., vol. 13, no. 3, pp. 036502:1–036502:16, July 2019.
    DOI: 10.1117/1.JRS.13.036502

  21. P. Markopoulos, N. Tsagkarakis, D. A. Pados, and G. N. Karystinos, “Realified L1-PCA for Direction-of-Arrival Estimation: Theory and Algorithms,” EURASIP J. Adv. Signal Process., no. 30, June 2019.
    DOI: 10.1186/s13634-019-0625-5

  22. P. Markopoulos, S. Zlotnikov, and F. Ahmad, “Adaptive Radar-Based Human Activity Recognition with L1-norm Linear Discriminant Analysis,” IEEE J. Electromagn. RF Microw. Med. Biol., vol. 3, no. 2, pp. 120–126, June 2019.
    DOI: 10.1109/JERM.2019.2893587

  23. P. Markopoulos, M. Dhanaraj^\dag and A. Savakis, “Adaptive L1-Norm Principal-Component Analysis with Online Outlier Rejection,” IEEE J. Sel. Topics Signal Process., vol. 12, no. 6, pp. 1131–1143, Dec. 2018.
    DOI: 10.1109/JSTSP.2018.2874165

  24. N. Tsagkarakis, P. Markopoulos, and D. A. Pados, “L1-Norm Principal-Component Analysis of Complex Data,” IEEE Trans. Signal Process., vol. 66, no. 12, pp. 3256–3267, June 2018.
    DOI: 10.1109/TSP.2018.2821641

  25. P. Markopoulos, D. G. Chachlakis^\dag and E. E. Papalexakis, “The Exact Solution to Rank-1 L1-Norm TUCKER2 Decomposition,” IEEE Signal Process. Lett., vol. 25, no. 4, pp. 511–515, Apr. 2018.
    DOI: 10.1109/LSP.2018.2790901

  26. P. Markopoulos and G. N. Karystinos, “Noncoherent Alamouti Phase-Shift Keying with Full-Rate Encoding and Polynomial-Complexity Maximum-Likelihood Decoding,” IEEE Trans. Wireless Commun., vol. 16, no. 10, pp. 6688–6697, July 2017.
    DOI: 10.1109/TWC.2017.2728524

  27. P. Markopoulos, S. Kundu, S. Chamadia, and D. A. Pados, “Efficient L1-Norm Principal-Component Analysis via Bit Flipping,” IEEE Trans. Signal Process., vol. 65, no. 16, pp. 4252–4264, Aug. 2017.
    DOI: 10.1109/TSP.2017.2708023

  28. P. Markopoulos, G. N. Karystinos, and D. A. Pados, “Optimal Algorithms for L1-Subspace Signal Processing,” IEEE Trans. Signal Process., vol. 62, no. 19, pp. 5046–5058, Oct. 2014.
    DOI: 10.1109/TSP.2014.2338077

  29. P. Markopoulos, S. Kundu, and D. A. Pados, “Small-Sample-Support Suppression of Interference to PN-Masked Data,” IEEE Trans. Commun., vol. 61, no. 7, pp. 2979–2987, July 2013.
    DOI: 10.1109/TCOMM.2013.043013.120643

  30. A. Bletsas, A. Vlachaki, E. Kampianakis, G. Sklivanitis, J. Kimionis, K. Tountas, M. Asteris, and P. Markopoulos, “Building a Low-Cost Digital Garden as a Telecom Lab Exercise,” IEEE Pervasive Computing, vol. 12, no. 1, pp. 48–57, Jan. 2013.
    DOI: 10.1109/MPRV.2011.83

Conference Proceeding Articles (Refereed)
Advisees are marked with (^\dag). Presenter is marked with (^\ddag).

  1. E. Moncada, J. G. Perez-Blanco, L. G. Hernández-Rojas, P. Markopoulos, and J. M. Antelis, “Modality Utilization in EEG–EMG Multimodal Neural Networks for Movement Detection,” in Proc. Mexican International Conference on Artificial Intelligence (MICAI 2026), 2026. Under review.

  2. V. T. Nguyen,^{\dag,\ddag} and P. Markopoulos, “VQBR: Variational Quantum Bayesian Regression via Measurement-Based MAP Direction Recovery,” in Proc. IEEE Int. Conf. Quantum Comput. Eng. (QCE), 2026. Under review.

  3. V. T. Nguyen,^{\dag,\ddag}, M. Dhanaraj^\dag, and P. Markopoulos, “Depth- and Rank-Selective Multilinear Transformation Layers for Compact CNNs,” in Proc. 56th Asilomar Conf. Signals, Syst., Comput., 2026. Under review.

  4. R. U. Haque,^{\dag,\ddag} and P. Markopoulos, “Robust Federated Learning via Stable Cosine Similarity,” in Proc. 2025 IEEE Int. Carnahan Conf. Security Technol. (ICCST), 2025.
    DOI: 10.1109/ICCST63435.2025.11295691
    \star Distinguished Paper Award

  5. R. U. Haque^\dag and P. Markopoulos^\ddag, “LG-XLR: Loss-Guided Exponential Learning Rate Adaptation,” in Proc. 2025 IEEE Int. Conf. Digit. Signal Process. (DSP), pp. 1–5, 2025.
    DOI: 10.1109/DSP65409.2025.11075054

  6. I. Tomeo,^{\dag,\ddag}, P. Markopoulos, and A. Savakis, “Robust Interbattery Factor Analysis by Uniform Sample Contributions,” in Signal Process., Sensor/Information Fusion, and Target Recognition XXXIV, Proc. SPIE 13479, pp. 384–390, May 2025.
    DOI: 10.1117/12.3058624

  7. D. Velychko^\ddag, S. Singh, P. Markopoulos, E. Saber, and J. Heard, “Image Preprocessing and YOLO Architectures for Enhanced Small and Slow-Moving Object Detection,” in Proc. 2024 IEEE WNY Image Signal Process. Workshop (WNYISPW), pp. 1–4, Nov. 2024.
    DOI: 10.1109/WNYISPW63690.2024.10786503

  8. M. Krol, R. Hyder, M. Peechatt, A. Prater-Bennette, M. S. Asif, and P. Markopoulos^\ddag, “Continual Learning in Convolutional Neural Networks with Tensor Rank Updates,” in Proc. 2024 IEEE 13th Sensor Array Multichannel Signal Process. Workshop (SAM), pp. 1–5, 2024.
    DOI: 10.1109/SAM60225.2024.10636545

  9. I. Tomeo,^{\dag,\ddag}, P. Markopoulos, and A. Savakis, “L1-PCA with Quantum Annealing,” in Proc. SPIE 13036, Big Data VI: Learning, Analytics, and Applications, National Harbor, MD, Apr. 2024, p. 1303605.
    DOI: 10.1117/12.3015944

  10. J. A. Sanchez Viloria^\ddag, D. Stripelis, P. Markopoulos, G. Sklivanitis, and D. A. Pados, “Adaptive Federated Learning for Automatic Modulation Classification Under Class and Noise Imbalance,” in Proc. AAAI 2024 Spring Symp. Series, Stanford, CA, Mar. 2024, p. 309.
    DOI: 10.1609/aaaiss.v3i1.31223

  11. S. Singh^\ddag, P. Markopoulos, E. Saber, J. D. Lew, and J. Heard, “Measuring Modality Utilization in Multi-Modal Neural Networks,” in Proc. IEEE Conf. Artif. Intell. (IEEE CAI), Santa Clara, CA, Jun. 2023, pp. 11–14.
    DOI: 10.1109/CAI54212.2023.00014

  12. S. Singh, M. Sharma^\dag, J. Heard, J. D. Lew, E. Saber, and P. Markopoulos^{\ddag}, “Multimodal Aerial View Object Classification with Disjoint Unimodal Feature Extraction and Fully-Connected-Layer Fusion,” in Proc. SPIE 12522, Big Data V: Learning, Analytics, and Applications, Orlando, FL, Apr. 2023, p. 1252206.
    DOI: 10.1117/12.2664041

  13. I. Tomeo,^{\dag,\ddag} and P. Markopoulos, “HDA: An Iterative Hyperplane-Search Method for Discriminant Analysis,” in Proc. SPIE 12538, AI and Machine Learning for Multi-Domain Operations Applications V, Orlando, FL, Apr. 2023, p. 125381U.
    DOI: 10.1117/12.2664331

  14. D. H. Le^\ddag and P. Markopoulos, “Robust Singular Values Based on L1-norm PCA,” in Proc. IEEE Workshop Signal Process. Syst. (IEEE SiPS), Rennes, France, Nov. 2022, pp. 1–6.
    DOI: 10.1109/SiPS55645.2022.9919215

  15. M. Dhanaraj,^{\dag,\ddag} and P. Markopoulos, “Robust Stochastic Principal Component Analysis via Barron Loss,” in Proc. IEEE Asilomar Conf. Signals, Syst., Comput. (IEEE ACSSC), Pacific Grove, CA, Oct. 2022, pp. 1286–1290.
    DOI: 10.1109/IEEECONF56349.2022.10051902

  16. R. Hyder^\ddag, K. Shao, B. Hou, P. Markopoulos, A. Prater-Bennette, and M. S. Asif, “Incremental Task Learning with Incremental Rank Updates,” in Proc. Eur. Conf. Comput. Vision (ECCV), Tel Aviv, Israel, Oct. 2022, pp. 566–582.
    DOI: 10.1007978-3-031-20050-2_34

  17. M. Sharma^\dag, P. Markopoulos^\ddag, E. Saber, M. S. Asif, and A. Prater-Bennette, “Convolutional Auto-Encoder with Tensor-Train Factorization,” in Proc. Int. Conf. Comput. Vision (ICCV), Montreal, QC, Canada, Oct. 2021, pp. 198–206.
    DOI: 10.1109/ICCVW54120.2021.00027

  18. M. Mozaffari^\ddag, P. Markopoulos, and A. Prater-Bennette, “Improved L1-Tucker via L1-Fitting,” in Proc. Eur. Signal Process. Conf. (EUSIPCO), Dublin, Ireland, Aug. 2021, pp. 1075–1079.
    DOI: 10.23919/EUSIPCO54536.2021.9616014

  19. M. Mozaffari^\ddag and P. Markopoulos, “Robust Barron-Loss Tucker Tensor Decomposition,” in Proc. IEEE Asilomar Conf. Signals, Syst., Comput., Pacific Grove, CA, Oct. 2021, pp. 1651–1655.
    DOI: 10.1109/IEEECONF53345.2021.9723232

  20. M. Sharma^\dag, P. Markopoulos^\ddag, and E. Saber, “YOLOrs-LITE: A Lightweight CNN for Real-time Object Detection in Remote Sensing,” in Proc. IEEE Int. Geosci. Remote Sens. Symp. (IGARSS), Brussels, Belgium, Jul. 2021, pp. 2604–2607.
    DOI: 10.1109/IGARSS47720.2021.9554418

  21. D. G. Chachlakis^\dag and P. Markopoulos^\ddag, “Novel Algorithms for Lp-quasi-norm Principal-Component Analysis,” in Proc. Eur. Signal Process. Conf. (EUSIPCO), Amsterdam, Netherlands, Jan. 2021, pp. 1045–1049.
    DOI: 10.23919/Eusipco47968.2020.9287335

  22. G. Sklivanitis^\ddag, P. Markopoulos, D. A. Pados, and R. Diamant, “Robust Graph Localization for Underwater Acoustic Networks,” in Proc. IEEE Underwater Commun. Netw. Conf. (UComms), Lerici, Italy, Aug. 2021, pp. 1–5.
    DOI: 10.1109/UComms50339.2021.9598114

  23. S. A. Mamun^\ddag, A. Ganguly, P. Markopoulos, A. Kwasinski, and M. Kwon, “What Can Ail Thee: New and Old Security Vulnerabilities of Wireless Datacenters,” in Proc. IEEE Global Commun. Conf. (GLOBECOM), Taipei, Taiwan, Dec. 2020, pp. 1–7.
    DOI: 10.1109/GLOBECOM42002.2020.9322619

  24. Y. Tsitsikas^\ddag, D. G. Chachlakis^\dag, E. Papalexakis, and P. Markopoulos, “L1-Norm RESCAL Decomposition,” in Proc. IEEE Asilomar Conf. Signals, Syst., Comput., Pacific Grove, CA, Nov. 2020, pp. 940–944.
    DOI: 10.1109/IEEECONF51394.2020.9443401

  25. D. Chachlakis^\ddag, A. Prater-Bennette, and P. Markopoulos, “L1-Norm Higher-order Orthogonal Iterations for Robust Tensor Analysis,” in Proc. IEEE Int. Conf. Acoust., Speech, Signal Process. (ICASSP), Barcelona, Spain, May 2020, pp. 4826–4830.
    DOI: 10.1109/ICASSP40776.2020.9053701

  26. M. Dhanaraj,^{\dag,\ddag}, M. Sharma^\dag, T. Sarkar, S. Karnam, D. G. Chachlakis^\dag, R. Ptucha, P. Markopoulos, and E. Saber, “Vehicle Detection from Multi-modal Aerial Imagery Using YOLOv3 with Mid-level Fusion,” in Proc. SPIE 11395, Big Data II: Learning, Analytics, and Applications, Anaheim, CA, Apr. 2020, p. 1139506.
    DOI: 10.1117/12.2558115

  27. K. Tountas^\ddag, D. G. Chachlakis^\dag, P. Markopoulos, and D. A. Pados, “Iteratively Re-weighted L1-PCA of Tensor Data,” in Proc. IEEE Asilomar Conf. Signals, Syst., Comput., Pacific Grove, CA, Oct. 2019, pp. 1658–1661.
    DOI: 10.1109/IEEECONF44664.2019.9048775

  28. D. G. Chachlakis,^{\dag,\ddag} and P. Markopoulos, “Combinatorial Search for the Lp-Norm Principal Component of a Matrix,” in Proc. IEEE Asilomar Conf. Signals, Syst., Comput., Pacific Grove, CA, Oct. 2019, pp. 1611–1615.
    DOI: 10.1109/IEEECONF44664.2019.9048980

  29. S. A. Mamun^\ddag, A. Ganguly, M. Kwon, A. Kwasinski, and P. Markopoulos, “Network-Aware Server Consolidation for Wireless Data Centers,” in Proc. Int. Conf. Netw. Future (NoF), Rome, Italy, Oct. 2019, pp. 58–65.
    DOI: 10.1109/NoF47743.2019.9014979

  30. D. Chachlakis^\ddag, Y. Tsitsikas, E. Papalexakis, and P. Markopoulos, “Robust Multi-Relational Learning with Absolute Projection RESCAL,” in Proc. IEEE Global Conf. Signal Inf. Process. (GlobalSIP), Ottawa, ON, Canada, Nov. 2019, pp. 1–5.
    DOI: 10.1109/GlobalSIP45357.2019.8969097

  31. M. Dhanaraj,^{\dag,\ddag} and P. Markopoulos, “Stochastic Principal Component Analysis via Mean Absolute Projection Maximization,” in Proc. IEEE Global Conf. Signal Inf. Process. (GlobalSIP), Ottawa, ON, Canada, Nov. 2019, pp. 1–5.
    DOI: 10.1109/GlobalSIP45357.2019.8969411

  32. G. Orru^\ddag, T. Cattai, S. Colonnese, G. Scarano, F. De Vico Fallani, P. Markopoulos, and D. A. Pados, “Deep L1-PCA of Time-Variant Data with Application to Brain Connectivity Measurements,” in Proc. Eur. Signal Process. Conf. (EUSIPCO), A Coruna, Spain, Sep. 2019, pp. 1–5.
    DOI: 10.23919/EUSIPCO.2019.8903169

  33. D. G. Chachlakis,^{\dag,\ddag}, M. Dhanaraj^\dag, P. Markopoulos, and A. Prater-Bennette, “Options for Multimodal Classification Based on L1-Tucker Decomposition,” in Proc. SPIE 10989, Big Data: Learning, Analytics, and Applications, Baltimore, MD, Apr. 2019, 109890O.
    DOI: 10.1117/12.2520140

  34. S. Zlotnikov^\ddag, P. Markopoulos, and F. Ahmad, “Incremental L1-Norm Linear Discriminant Analysis for Indoor Human Activity Classification,” in Proc. IEEE Radar Conf. (RadarConf), Boston, MA, Apr. 2019, pp. 1–4.
    DOI: 10.1109/RADAR.2019.8835593

  35. P. Markopoulos^{\ddag}, D. G. Chachlakis^\dag, and A. Prater-Bennette, “L1-Norm Higher-Order Singular-Value Decomposition,” in Proc. IEEE Global Conf. Signal Inf. Process. (GlobalSIP), Anaheim, CA, Nov. 2018, pp. 1353–1357.
    DOI: 10.1109/GlobalSIP.2018.8646384

  36. K. Bichave^\ddag, O. Brewer, M. Gusinov, P. Markopoulos, and I. Puchades, “Gait Recognition Based on Tensor Analysis of Acceleration Data from Wearable Sensors,” in Proc. IEEE Western New York Image Signal Process. Workshop (WNYISPW), Rochester, NY, Oct. 2018, pp. 1–5.
    DOI: 10.1109/WNYIPW.2018.8576383
    \star Best Poster Award Runner-up

  37. M. Dhanaraj,^{\dag,\ddag}, D. G. Chachlakis^\dag, and P. Markopoulos, “Incremental Complex L1-PCA for Direction-of-Arrival Estimation,” in Proc. IEEE Western New York Image Signal Process. Workshop (WNYISPW), Rochester, NY, Oct. 2018, pp. 1–5.
    DOI: 10.1109/WNYIPW.2018.8576444

  38. A. Gannon^\ddag, G. Sklivanitis, P. Markopoulos, D. A. Pados, and S. N. Batalama, “Semi-Blind Signal Recovery in Impulsive Noise with L1-Norm PCA,” in Proc. IEEE Asilomar Conf. Signals, Syst., Comput., Pacific Grove, CA, Oct. 2018, pp. 477–481.
    DOI: 10.1109/ACSSC.2018.8645514

  39. M. Dhanaraj,^{\dag,\ddag} and P. Markopoulos, “Novel Algorithm for Incremental L1-Norm Principal-Component Analysis,” in Proc. Eur. Signal Process. Conf. (EUSIPCO), Rome, Italy, Sep. 2018, pp. 2020–2024.
    DOI: 10.23919/EUSIPCO.2018.8553234

  40. P. Markopoulos^{\ddag} and F. Ahmad, “Robust Radar-Based Human Motion Recognition with L1-Norm Linear Discriminant Analysis,” in Proc. IEEE Int. Microw. Biomed. Conf. (IMBioC), Philadelphia, PA, Jun. 2018, pp. 145–147.
    DOI: 10.1109/IMBIOC.2018.8428927

  41. D. G. Chachlakis,^{\dag,\ddag}, P. Markopoulos, and F. Ahmad, “MMSE-Based Autocorrelation Sampling for Coprime Arrays,” in Proc. IEEE Int. Conf. Acoust., Speech, Signal Process. (ICASSP), Calgary, AB, Canada, Apr. 2018, pp. 3474–3478.
    DOI: 10.1109/ICASSP.2018.8461676

  42. D. G. Chachlakis,^{\dag,\ddag} and P. Markopoulos, “Novel Algorithms for Exact and Efficient L1-Norm-Based TUCKER2 Decomposition,” in Proc. IEEE Int. Conf. Acoust., Speech, Signal Process. (ICASSP), Calgary, AB, Canada, Apr. 2018, pp. 6294–6298.
    DOI: 10.1109/ICASSP.2018.8461834

  43. D. G. Chachlakis,^{\dag,\ddag} and P. Markopoulos, “Robust Decomposition of 3-Way Tensors Based on L1-Norm,” in Proc. SPIE 10658, Compressive Sensing VII, Orlando, FL, Apr. 2018, p. 1065807.
    DOI: 10.1117/12.2307844

  44. S. Zlotnikov^\ddag, P. Somaru, P. Markopoulos, and F. Ahmad, “A Linear Discriminative Analysis Based Fall Motion Detector Using Radar,” in Proc. SPIE 10658, Compressive Sensing VII, Orlando, FL, Apr. 2018, p. 106580D.
    DOI: 10.1117/12.2311574

  45. D. G. Chachlakis,^{\dag,\ddag}, P. Markopoulos, and F. Ahmad, “The Mean-Squared-Error of Autocorrelation Sampling in Coprime Arrays,” in Proc. IEEE Int. Workshop Comput. Adv. Multi-Sensor Adapt. Process. (CAMSAP), Curacao, Dutch Antilles, Dec. 2017, pp. 1–5.
    DOI: 10.1109/CAMSAP.2017.8313121

  46. P. Markopoulos^{\ddag} and F. Ahmad, “Indoor Human Motion Classification by L1-Norm Subspaces of Micro-Doppler Signatures,” in Proc. IEEE Radar Conf. (RadarConf), Seattle, WA, May 2017, pp. 1807–1810.
    DOI: 10.1109/RADAR.2017.7944504

  47. P. Markopoulos^{\ddag}, D. A. Pados, G. N. Karystinos, and M. Langberg, “L1-Norm Principal-Component Analysis in L2-Norm-Reduced-Rank Data Subspaces,” in Proc. SPIE 10211, Compressive Sensing VI, Anaheim, CA, Apr. 2017, p. 1021104.
    DOI: 10.1117/12.2263733

  48. D. G. Chachlakis,^{\dag,\ddag}, P. Markopoulos, R. J. Muchhala, and A. Savakis, “Visual Tracking with L1-Grassmann Manifold Modeling,” in Proc. SPIE 10211, Compressive Sensing VI, Anaheim, CA, Apr. 2017, p. 1021102.
    DOI: 10.1117/12.2263691

  49. G. Sklivanitis^\ddag, P. Markopoulos, S. Batalama, and D. A. Pados, “Adaptive Sparse-Binary Waveform Design for All-Spectrum Channelization,” in Proc. SPIE 10211, Compressive Sensing VI, Anaheim, CA, Apr. 2017, p. 102110B.
    \star Student Travel Grant Award

  50. P. Markopoulos^{\ddag}, “Linear Discriminant Analysis with Few Training Data,” in Proc. IEEE Int. Conf. Acoust., Speech, Signal Process. (ICASSP), New Orleans, LA, Mar. 2017, pp. 4626–4630.
    DOI: 10.1109/ICASSP.2017.7953033

  51. G. Sklivanitis^\ddag, P. Markopoulos, S. Batalama, and D. A. Pados, “Sparse Waveform Design for All-Spectrum Channelization,” in Proc. IEEE Int. Conf. Acoust., Speech, Signal Process. (ICASSP), New Orleans, LA, Mar. 2017, pp. 3764–3768.
    DOI: 10.1109/ICASSP.2017.7952860

  52. N. Tsagkarakis^\ddag, P. Markopoulos, and D. A. Pados, “On the L1-norm Approximation of a Matrix by Another of Lower Rank,” in Proc. IEEE Int. Conf. Mach. Learn. Appl. (ICMLA), Anaheim, CA, Dec. 2016, pp. 768–773.
    DOI: 10.1109/ICMLA.2016.0137

  53. P. Markopoulos^{\ddag}, S. Kundu, S. Chamadia, and D. A. Pados, “L1-Norm Principal-Component Analysis via Bit Flipping,” in Proc. IEEE Int. Conf. Mach. Learn. Appl. (ICMLA), Anaheim, CA, Dec. 2016, pp. 326–332.
    DOI: 10.1109/ICMLA.2016.0060

  54. P. Markopoulos^{\ddag}, N. Tsagkarakis, D. A. Pados, and G. N. Karystinos, “Direction-of-Arrival Estimation from L1-Norm Principal Components,” in Proc. IEEE Int. Symp. Phased Array Syst. Technol. (PAST), Waltham, MA, Oct. 2016, pp. 1–6.
    DOI: 10.1109/ARRAY.2016.7832585

  55. Y. Liang^\ddag, P. Markopoulos, and E. Saber, “Subpixel Target Detection in Hyperspectral Images with Local Matched Filtering in SLIC Superpixels,” in Proc. IEEE Workshop Hyperspectral Image Signal Process. (WHISPERS), Los Angeles, CA, Aug. 2016, pp. 1–5.
    DOI: 10.1109/WHISPERS.2016.8071719

  56. P. Markopoulos^{\ddag}, “Reduced-Rank Filtering on L1-Norm Subspaces,” in Proc. IEEE Sensor Array Multichannel Signal Process. Workshop (SAM), Rio de Janeiro, Brazil, Jul. 2016, pp. 1–5.
    DOI: 10.1109/SAM.2016.7569743

  57. Y. Liang^\ddag, P. Markopoulos, and E. Saber, “Subpixel Target Detection in Hyperspectral Images from Superpixel Background Statistics,” in Proc. IEEE Int. Geosci. Remote Sens. Symp. (IGARSS), Beijing, China, Jul. 2016, pp. 7018–7021.
    DOI: 10.1109/IGARSS.2016.7730830

  58. P. Markopoulos^{\ddag}, S. Kundu, and D. A. Pados, “L1-Fusion: Robust Linear-Time Image Recovery from Few Severely Corrupted Copies,” in Proc. IEEE Int. Conf. Image Process. (ICIP), Quebec City, QC, Canada, Sep. 2015, pp. 1225–1229.
    DOI: 10.1109/ICIP.2015.7350995

  59. N. Tsagkarakis^\ddag, P. Markopoulos, and D. A. Pados, “Direction Finding by Complex L1-Principal Component Analysis,” in Proc. IEEE Int. Workshop Signal Process. Adv. Wireless Commun. (SPAWC), Stockholm, Sweden, Jun. 2015, pp. 475–479.
    DOI: 10.1109/SPAWC.2015.7227083

  60. P. Markopoulos^{\ddag}, N. Tsagkarakis, D. A. Pados, and G. N. Karystinos, “Direction Finding with L1-Norm Subspaces,” in Proc. SPIE 9109, Compressive Sensing III, Baltimore, MD, May 2014, p. 91090J.
    DOI: 10.1117/12.2053049
    \star Student Travel Grant Award

  61. S. Kundu^\ddag, P. Markopoulos, and D. A. Pados, “Fast Computation of the L1-Principal Component of Real-Valued Data,” in Proc. IEEE Int. Conf. Acoust., Speech, Signal Process. (ICASSP), Florence, Italy, May 2014, pp. 8028–8032.
    DOI: 10.1109/ICASSP.2014.6855164

  62. P. Markopoulos^{\ddag}, G. N. Karystinos, and D. A. Pados, “Some Options for L1-Subspace Signal Processing,” in Proc. IEEE Int. Symp. Wireless Commun. Syst. (ISWCS), Ilmenau, Germany, Aug. 2013, pp. 622–626.
    \star Best Paper Award in Physical Layer Communications

  63. P. Markopoulos^{\ddag} and G. N. Karystinos, “Novel Full-Rate Noncoherent Alamouti Encoding that Allows Polynomial-Complexity Optimal Decoding,” in Proc. IEEE Int. Conf. Acoust., Speech, Signal Process. (ICASSP), Vancouver, BC, Canada, May 2013, pp. 5075–5079.
    DOI: 10.1109/ICASSP.2013.6638628

  64. P. Markopoulos^{\ddag}, S. Kundu, and D. A. Pados, “Short-Data-Record Filtering of PN-Masked Data,” in Proc. IEEE Int. Conf. Acoust., Speech, Signal Process. (ICASSP), Vancouver, BC, Canada, May 2013, pp. 4559–4563.
    DOI: 10.1109/ICASSP.2013.6638523

  65. A. Bletsas, A. Vlachaki, E. Kampianakis^\ddag, G. Sklivanitis, J. Kimionis, K. Tountas, M. Asteris, and P. Markopoulos, “Towards Precision Agriculture: Building a Soil Wetness Multi-Hop WSN from First Principles,” in Proc. Int. Workshop Sensing Technol. Architecture, Forestry Environ. (ECOSENSE), Belgrade, Serbia, Apr. 2011, pp. 1–4. 7)

Book Chapters (Invited, Non-Refereed)

  1. D. G. Chachlakis^\dag, M. Dhanaraj^\dag, P. Markopoulos, and A. Prater-Bennette, “Dynamic and Robust Analysis of Tensor Data in the DDDAS Framework,” in Handbook of Dynamic Data-Driven Application Systems (Vol. III), E. P. Blasch, F. Darema, S. Ravela, and A. J. Aved, Eds. Springer, Cham, Jun. 2026.
    ISBN: 978-3-031-88573-0

  2. F. Ahmad and P. Markopoulos, “L1-Norm Principal Component and Discriminant Analyses of Micro-Doppler Signatures for Indoor Human Activity Recognition,” in Micro-Doppler Radar and its Applications, F. Fioranelli, M. Ritchie, A. Balleri, and H. Griffiths, Eds. IET Press, 2020.
    DOI: 10.1049/SBRA531E_ch11

  3. P. Markopoulos, S. Kundu, S. Chamadia, N. Tsagkarakis, and D. A. Pados, “Outlier-Resistant Data Processing with L1-norm Principal Component Analysis,” in Advances in Principal Component Analysis: Research and Development, G. R. Naik, Ed. Springer, 2018.
    DOI: 10.1007/978-981-10-6704-4_6

Talks & Tutorials

Refereed Conference Presentations
All presentations associated with refereed conference papers are listed in detail above, under subsection “Conference Proceeding Articles (Refereed)”, where the presenter is marked with (^\ddag).

Invited Talks

  1. P. Markopoulos, “Tensor Methods for Efficient, Robust, and Continual Machine Learning,” presented at GRDS-SPIE Seminar, Univ. of Texas at Rio Grande Valley, Apr. 2026.

  2. P. Markopoulos, “Towards Trustworthy and Privacy-Preserving Federated Learning: Methods, Challenges, and Applications,” presented at Biomedical Engineering (BME) Seminar Series, UT San Antonio, San Antonio, TX, Oct. 2025.

  3. P. Markopoulos, “Quantum Computing at The University of Texas at San Antonio,” presented at First Texas Quantum Summit, Texas A&M Univ., College Station, TX, Sept. 2025.

  4. P. Markopoulos, “Advances in Robust and Efficient Machine Learning for National Security,” presented at Dept. of Defense (16th Air Force / TD), Aug. 2023.

  5. P. Markopoulos, “Tensor Methods for Efficient, Robust, and Continual Machine Learning,” presented at MATRIX AI Seminar Series, UT San Antonio, San Antonio, TX, Sept. 2022.

  6. P. Markopoulos, “Advances in Robust Machine Learning,” presented at Intelligence Community Academic Research Symposium (ICARS), National Academies of Sciences, Engineering, and Medicine, Sept. 2022.

  7. P. Markopoulos, “Advances in Robust Machine Learning,” presented at ICARS, National Academies of Sciences, Engineering, and Medicine, Sept. 2021.

  8. P. Markopoulos, “L1-norm PCA: Algorithms and Applications,” presented at Graduate Seminar, RIT, Rochester, NY, May 2021.

  9. P. Markopoulos, “Tensor Methods for Imaging Science,” presented at Center for Imaging Science, RIT, Rochester, NY, Nov. 2020.

  10. P. Markopoulos, “Tensor Methods Based on Absolute Projections,” presented at Applied Mathematics Seminar, Syracuse Univ., Syracuse, NY, Oct. 2020.

  11. P. Markopoulos, “Improving CNNs Towards Real-Time Multi-Modal Object Detection in Remote Sensing Imagery,” presented at ICARS, National Academies of Sciences, Engineering, and Medicine, Sept. 2020.

  12. P. Markopoulos, “Tensor Methods for Image Processing,” presented at SIAM IS20, Tensor Methods for Image Processing Mini-Symposium, Toronto, Canada, July 2020.

  13. P. Markopoulos, “Improving CNNs Towards Real-Time Multi-Modal Object Detection in Remote Sensing Imagery,” presented at National Geospatial-Intelligence Agency (NGA), July 2020.

  14. P. Markopoulos, “Tensor Methods for Robust Machine Learning,” presented at U.S. Air Force Research Laboratory (AFRL/RI), Rome, NY, Apr. 2020.

  15. P. Markopoulos, “Robust Subspace Learning and Applications in Computer Vision,” presented at ICCV Workshop on Robust Subspace Learning, Seoul, Korea, Oct. 2019.

  16. P. Markopoulos, “L1-norm PCA: Algorithms and Applications,” presented at U.S. Air Force Research Laboratory (AFRL), Rome, NY, June 2018.

  17. P. Markopoulos, “Tensor Methods for Imaging and Sensing,” presented at Institute for Sensing and Embedded Network Systems Engineering (I-SENSE), Florida Atlantic Univ., Boca Raton, FL, May 2018.

  18. P. Markopoulos, “Robust Subspace Processing,” presented at MSEE Graduate Seminar, RIT, Rochester, NY, Apr. 2018.

  19. P. Markopoulos, “L1-norm Methods for Signal Processing and Machine Learning,” presented at Move78 / AI and Cognitive Technologies Speaker Series, RIT, Rochester, NY, Jan. 2018.

  20. P. Markopoulos, “Robust Subspace Processing and Machine Learning,” presented at Univ. of Rochester (IEEE Rochester Section, AES/COMSOC), Rochester, NY, Nov. 2016.

  21. P. Markopoulos, “L1-norm Tensor Methods Based on Absolute Projections,” presented at Dept. of Electrical and Microelectronic Engineering, RIT, Rochester, NY, Mar. 2015.

  22. P. Markopoulos, “Tensor Methods for Communications and Signal Processing,” presented at Dept. of Electrical and Computer Engineering, Northeastern Univ., Boston, MA, Oct. 2014.

Tutorials and Short Courses

  1. P. Markopoulos, “Federated Learning for Decentralized and Privacy-Preserving Machine Learning,” tutorial presented at SPIE DCS 2025, Machine Learning from Challenging Data Conf., Apr. 2025.

  2. P. Markopoulos, “Federated Learning in Healthcare: A Brief Review of Foundations, Applications, Challenges, and Opportunities,” tutorial presented at NSF AI Spring School, UT San Antonio, San Antonio, TX, Feb. 2025.

  3. P. Markopoulos, “Federated Learning: Introductory Tutorial,” tutorial presented at Dynamic Data-Driven Application Systems (DDDAS), Nov. 2024.

  4. P. Markopoulos, “Tensor Methods for Signal Processing and Machine Learning,” tutorial presented at Summer School on Data Science, Technical Univ. of Crete, Chania, Greece, Aug. 2020.

  5. P. Markopoulos, “L1-norm Principal Component Analysis of Multi-Modal Data,” tutorial presented at Summer School, Technical Univ. of Crete, Chania, Greece, July 2018.

Other Presentations

  1. P. Markopoulos, “L1-norm Methods for Communications and Signal Processing,” poster presented at IEEE North American School of Information Theory, Toronto, Canada, June 2014.

Patents

Funding

Pending Proposals Available upon request.

Current Grants

Previous Grants

Teaching

Career-wide teaching metrics (enrollment-weighted averages, as of June 10, 2026):

Below, “YYYY-T (E)” denotes year ‘YYYY’, term ‘T’, and enrollment (over all sections) ‘E’
Courses at UT San Antonio (2022–present)

Courses at RIT (2015–2022)

Courses at UB (before 2015, as Graduate Student)

Student Mentoring

Doctoral Advisees

Current

Graduated

M.S. and B.S. Advisees

Current

Graduated

Over 25 past M.S./B.S. advisees, working on theses, graduate papers, volunteering, funded research assistantships.

Thesis/Dissertation Committees

Over 30 graduate/doctoral thesis/dissertation committees.

Service

Leadership and Service at UT San Antonio

University Level

College Level (CAICC and KCEID)

Department Level (CE and ECE)

Academic Service at Rochester Institute of Technology

University Level

College Level

Department Level

Service at Federal Agencies

Leadership and Editorial Roles

Conference Organization

Conference Technical Program Committees

Paper Reviews

Outreach