Spring til indhold.

Department of Computer Science

PhD Defence by Zhichen Lai

On Friday, March 14, Zhichen Lai will defend his PhD thesis: "Efficient Deep Learning for Correlated Time Series Analytics".

Room 0.2.13,
Selma Lagerløfs Vej 300,
9220 Aalborg Øst

  • 14.03.2025 Kl. 09:00 - 12:00

  • English

  • On location

Room 0.2.13,
Selma Lagerløfs Vej 300,
9220 Aalborg Øst

14.03.2025 Kl. 09:00 - 12:00

English

On location

Department of Computer Science

PhD Defence by Zhichen Lai

On Friday, March 14, Zhichen Lai will defend his PhD thesis: "Efficient Deep Learning for Correlated Time Series Analytics".

Room 0.2.13,
Selma Lagerløfs Vej 300,
9220 Aalborg Øst

  • 14.03.2025 Kl. 09:00 - 12:00

  • English

  • On location

Room 0.2.13,
Selma Lagerløfs Vej 300,
9220 Aalborg Øst

14.03.2025 Kl. 09:00 - 12:00

English

On location

Abstract

The extensive deployment of sensors in Cyber-Physical Systems (CPSs) enable continuous monitoring of physical processes, generating Correlated Time Series (CTS) data with both temporal and spatial correlations. Temporal correlations link consecutive measurements within a time series, such as heart rate fluctuations over time in healthcare monitoring. Spatial correlations connect multiple sensors, like wind speed and direction measurements across turbines in a wind farm.

However, existing deep learning-based methods struggle to balance accuracy and computational efficiency in CTS analytics, limiting their use in resource-constrained environments. This thesis addresses this challenge through five key contributions:

  1. LightCTS – an efficient CTS forecasting framework leveraging lightweight temporal and spatial modules, achieving state-of-the-art accuracy with reduced computational overhead.
  2. LightCTS⋆ – an extension incorporating model distillation to enhance efficiency without sacrificing accuracy.
  3. E2USD – an efficient CTS state detection framework using a compact embedding encoder for contrastive learning and adaptive thresholds for online streaming detection, validated on MCUs.
  4. ReCTSi – an efficient CTS imputation framework employing decoupled pattern learning for accurate imputation with minimal computational cost.
  5. AdaCTSi – an adaptive CTS imputation framework dynamically tailoring its operations to on-demand scenarios, achieving state-of-the-art performance in both imputation accuracy and resource adaptability.

Together, these contributions advance CTS analytics by introducing efficient, effective, and adaptive deep learning methods, addressing critical efficiency challenges in CTS processing.

All interested parties are welcome. After the defence the department will be hosting a small reception in cluster 3. 

Attendees

in the defence
Assessment committee
  • Professor Baltasar Beferull-Lozano from SIMULA
  • Metropolitan, Norway
  • Professor Yongluan Zhou from the University of Copenhagen,
  • Denmark
  • Associate Professor Andrés R. Masegosa (chair), Aalborg University,
  • Denmark
Moderator
  • Associate Professor Simonas Saltenis, Aalborg University, Denmark
PhD supervisor
  • Professor Christian S. Jensen, Aalborg University
Co-supervisors
  • Associate Professor Dalin Zhang, Aalborg University, Denmark (also
  • affiliated with Hangzhou Dianzi University, China)
  • Professor Huan Li, Zhejiang University, China (formerly at Aalborg University, Denmark)