I'm Hangdong, a CS Ph.D. at University of Wisconsin-Madison, advised by Prof. Paraschos Koutris. I'm a member of the UW-Madison Database Group. I have broad interests in Database Systems. So far, my work has been focusing on theory and practice of query optimization.

Previously, I got my B.Sc. in Mathematics from the National University of Singapore in 2020. I was fortunate to work with Prof. Jonathan Scarlett on neural architecture search.

---

Publications (* - alphabetical authorship following the norm of theoretical papers)

• Conjunctive Queries with Negation and Aggregation: A Linear Time Characterization [to appear]
  Hangdong Zhao, Austen Z. Fan, Xiating Ouyang and Paraschos Koutris
  PODS'24 @ Santiago, Chile

• *The Fine-Grained Complexity of Boolean Conjunctive Queries and Sum-Product Problems [slides]
  Austen Z. Fan, Paraschos Koutris, Hangdong Zhao
  ICALP'23 @ Paderborn, Germany

• Space-Time Tradeoffs for Conjunctive Queries with Access Patterns [slides]
  Hangdong Zhao, Shaleen Deep, Paraschos Koutris
  PODS'23 @ Seattle, WA
  Distinguished Paper Award

• On Architecture Selection for Linear Inverse Problems with Untrained Neural Networks
  Yang Sun, Hangdong Zhao, Jonathan Scarlett
  Entropy, 23(11), 1481 @ Basel, Switzerland

---

Work Experience

• National University of Singapore (Jun 2020 - Aug 2021)
  Research Assistant @ Singapore

---

Teaching

• [TA] CS 577 Intro to Algorithms: Spring 2022, Fall 2021

• [TA] CS 544 Intro to Big Data Systems: Fall 2023