Yong Liu

刘勇

Lecturer · Mathematical Logic & Computability Theory

School of Information Engineering · Nanjing Xiaozhuang University

Emailliuyong@njxzc.edu.cn

Office

Room 612, South Engineering Building, Nanjing Xiaozhuang University

Address

3601 Hongjing Avenue, Jiangning District, Nanjing 211171, China

I was born in Nanjing. I studied at the High School Affiliated to Nanjing Normal University and Nanjing Normal University before pursuing graduate studies at the National University of Singapore, where I received my master’s and Ph.D. degrees. I subsequently held research positions at the National University of Singapore and Nanyang Technological University. After returning to China, I worked as a researcher in the Department of Mathematics (now the School of Mathematics) at Nanjing University. I am currently a lecturer in the School of Information Engineering at Nanjing Xiaozhuang University.

Research interests

Mathematical logic and computability theory, with a particular focus on computability-theoretic degree structures, the Ershov hierarchy, inductive strength, and priority methods.

Yiqun Liu, Yong Liu, Cheng Peng. “Isolated d.c.e. Degrees and Σ₁ Induction.” Annals of Pure and Applied Logic, 2026, 177(3): 103678. [doi:10.1016/j.apal.2025.103678]
Yong Liu, Cheng Peng, Mengzhou Sun. “Robinson Splitting Theorem and Σ₁ Induction.” Journal of Symbolic Logic, 2026. [doi:10.1017/jsl.2026.10244]
Yong Liu, Cheng Peng. “Weak Density and Nondensity among Transfinite Levels of the Ershov Hierarchy.” Notre Dame Journal of Formal Logic, 2020, 61(4): 521–536. [doi:10.1215/00294527-2020-0023]

All publications and academic activities

Teaching

Current courses: Combinatorics, Discrete Mathematics, Point-Set Topology, and Advanced Mathematics II. Previously taught: Calculus, Linear Algebra, and Probability and Mathematical Statistics.

Combinatorics

组合数学

Counting methods, recurrence relations, and generating functions.

Lecture notes (PDF)

Discrete Mathematics

离散数学

Propositional logic, an introduction to first-order logic, sets, and relations.

Lecture notes (PDF)

Point-Set Topology

点集拓扑

Metric spaces, topological spaces, continuous maps, connectedness, and compactness.

Lecture notes (PDF): forthcoming

Advanced Mathematics II

高等数学II

Multivariable calculus and an introduction to ordinary differential equations.