Qingsong Liu

Postdoctoral Research Associate
Manning College of Information and Computer Sciences (CICS)
University of Massachusetts Amherst (UMass)
Email: thulqs15@gmail.com

About Me

I am currently a Postdoctoral Research Associate at the University of Massachusetts Amherst, working with Prof. Mohammad Hajiesmaili since October 2024. Before joining UMass, I received my Ph.D. in July 2024 from the Institute for Interdisciplinary Information Sciences (IIIS), Tsinghua University, where I was supervised by Prof. Zhixuan Fang. Prior to that, I achieved my Bachelor's degree in July 2019 at the Department of Electronic Engineering of Tsinghua University and worked with Prof. Wenfei Wu.

Research Interests

Constrained Online Optimization and Learning
Performance Modeling and Optimization in Computer Systems and Communication Networks

Conference Papers

Q. Liu and M. Hajiesmaili, "A Unified Framework for Online Combinatorial Allocation of Reusable Resources under Endogenous Deterioration," ACM SIGMETRICS, 2026.
A. Joshi*, Q. Liu*, and M. Hajiesmaili, "Learning to Allocate Reusable Resources under Stochastic Rewards and Durations," ACM SIGMETRICS, 2026.
A. Zeynali, M. Sahebdel, Q. Liu, R. Sitaraman, and M. Hajiesmaili, "Smoothed Online Optimization for Target Tracking: Robust and Learning-Augmented Algorithms," ALT, 2026.
S. Fang, Q. Liu, Y. Xu, W. Gao, J. Nie, and W. Wu, "TurboTSS: A Packet Classifier with Fast Rule Lookup and Update for the Cloud," IEEE INFOCOM, 2026.
Z. Jia, H. Fan, X. Gu, B. Li, W. Wang, and Q. Liu, "AoI-Constrained Scheduling for Information Freshness over Unreliable Channels," IEEE/ACM IWQoS, 2025.
Z. Jia*, Q. Liu*, H. Fan, X. Gu, B. Li, and W. Wang, "Learning to Optimize Resource Utilization with QoS Guarantees," IEEE INFOCOM, 2025.
Q. Liu and M. Hajiesmaili, "Online Fair Allocation of Reusable Resources," ACM SIGMETRICS, 2025.
Y. Huang*, Q. Liu*, and J. Xu, "Adversarial Combinatorial Bandits with Switching Cost and Arm Selection Constraints," IEEE INFOCOM, 2024.
Q. Liu, W. Xu, and Z. Fang, "Learning-based Scheduling for Information Gathering with QoS Constraints," IEEE INFOCOM, 2024.
Q. Liu and Z. Fang, "Learning the Optimal Control for Evolving Systems with Converging Dynamics," ACM SIGMETRICS, 2024.
Q. Liu and Z. Fang, "Decentralized Scheduling with QoS Constraints: Achieving O(1) QoS regret," AAAI, 2024.
Q. Liu and Z. Fang, "Learning to Schedule Tasks with Deadline and Throughput Constraints," IEEE INFOCOM, 2023.
Q. Liu*, W. Xu*, S. Wang, and Z. Fang, "Combinatorial Bandits with Linear Constraints: Beyond Knapsacks and Fairness," NeurIPS, 2022.
Q. Liu, Z. Li, and Z. Fang, "Online Convex Optimization with Switching Costs: Algorithms and Performance," IEEE WiOpt, 2022.
Q. Liu, W. Wu, L. Huang, and Z. Fang, "Simultaneously Achieving Sublinear Regret and Constraint Violations for Online Convex Optimization with Time-varying Constraints," IFIP Performance, 2021.

Journal Papers

Q. Liu, Z. Li, and Z. Fang, "Smoothed Online Decision Making in Communication: Algorithms and Applications," IEEE/ACM Transactions on Networking, 2024.
Z. Jia*, Q. Liu*, J. Zhou, X. Gu, Y. Zhang, B. Li, and W. Wang, "Optimal Caching for Partial-observation Regime and Beyond," IEEE Transactions on Services Computing, 2024.
Q. Liu and Z. Fang, "Online Task Scheduling and Termination with Throughput Constraint," IEEE/ACM Transactions on Networking, 2024.
Y. Zhang, Q. Liu, J. Sun, and C. Wu, "The Optimal Dynamic Regret for Smoothed Online Convex Optimization with Squared Norm Switching Costs," Journal of the Franklin Institute, 2023.
Q. Liu, W. Wu, L. Huang, and Z. Fang, "Simultaneously Achieving Sublinear Regret and Constraint Violations for Online Convex Optimization with Time-varying Constraints," Elsevier's Performance Evaluation (PEVA), volume 152, 2021.

Academic Service

Program Committee Member/Conference Reviewer:

AISTATS (2023, 2024, 2025), NeurIPS (2023, 2024, 2025, 2026), ICML (2024, 2025, 2026), ICLR (2024, 2025, 2026), ACM SIGMETRICS (2026)

Journal Reviewer:

IEEE TMC, IEEE TNNLS, ACM TOMPECS, IEEE/ACM TON

Teaching