Timothy Ng

I'm an Associate Instructional Professor in the Department of Computer Science at the University of Chicago.

Mail
Department of Computer Science
University of Chicago
5730 S. Ellis Ave.
Chicago, IL 60637
Office
JCL 156
E-mail
timng@uchicago.edu

As an instructional professor, I'm a member of the teaching faculty in the department. My main teaching interests are in the mathematical foundations of computer science. I teach courses in the introductory and theory sequences for the Computer Science major in the College and have taught various theory courses for master's programs offered by the Department of Computer Science.

I am not currently active in research. I'm a theoretical computer scientist by training. Previously, I did research in formal languages and automata theory. I was a postdoctoral fellow in the Cheriton School of Computer Science at the University of Waterloo working with Lila Kari. I completed my PhD at Queen's University, under the supervision of Kai Salomaa and David Rappaport.

Teaching

Currently

Spring 2026
CMSC 28000: Introduction to Formal Languages (×2)

Previously

CMSC 14100
Introduction to Computer Science I
CMSC 15100
Introduction to Computer Science I
CMSC 27100
Discrete Mathematics
CMSC 27200
Theory of Algorithms
CMSC 28000
Introduction to Formal Languages
CAPP 30271
Mathematics for Computer Science and Data Analysis
MPCS 50103
Mathematics for Computer Science: Discrete Mathematics
MPCS 55001
Algorithms
Other

Research

A list of my publications has also been reproduced (to varying degrees of completeness) at DBLP, ORCID, and Google Scholar. My Erdős Number is 2, via [17].

Journal articles

  1. F. Bellamoli, G. Franco, L. Kari, S. Lampis, T. Ng, and Z. Wang. Conjugate word blending: formal model and experimental implementation by XPCR. Natural Computing 20, 647–658, 2021.
  2. L. Kari and T. Ng. Descriptional Complexity of Semi-Simple Splicing Systems. International Journal of Foundations of Computer Science 32(06), 685–711, 2021.
  3. Y.-S. Han, S.-K. Ko, T. Ng, and K. Salomaa. Consensus String Problem for Multiple Regular Languages. Information and Computation 279, 104615, 2021.
  4. Y.-S. Han, S.-K. Ko, T. Ng, and K. Salomaa. Closest Substring Problems for Regular Languages. Theoretical Computer Science 862, 144–154, 2021.
  5. S.K. Enaganti, L. Kari, T. Ng, and Z. Wang. Word blending in formal languages. Fundamenta Informaticae 171(1–4), 151–173, 2020.
  6. T. Ng, D. Rappaport, and K. Salomaa. State Complexity of Suffix Distance. International Journal of Foundations of Computer Science 30(06&07), 203–214, 2019.
  7. T. Ng, D. Rappaport, and K. Salomaa. State Complexity of Neighbourhoods and Approximate Pattern Matching. International Journal of Foundations of Computer Science 29(02), 315–329, 2018.
  8. D.-J. Cho, Y.-S. Han, T. Ng, and K. Salomaa. Outfix-Guided Insertion. Theoretical Computer Science 701, 70–84, 2017.
  9. D.-J. Cho, Y.-S. Han, T. Ng, and K. Salomaa. Pseudoknot-Generating Operation. Theoretical Computer Science 696, 52–64, 2017.
  10. T. Ng, D. Rappaport, and K. Salomaa. State Complexity of Prefix Distance of Subregular Languages. Journal of Languages, Automata, and Combinatorics 22(1–3), 169–188, 2017.
  11. T. Ng, D. Rappaport, and K. Salomaa. State Complexity of Prefix Distance. Theoretical Computer Science 679, 107–117, 2017.
  12. Y.-S. Han, S.-K. Ko, T. Ng, and K. Salomaa. State Complexity of Insertion. International Journal of Foundations of Computer Science 27(07), 863–878, 2016.

Conference articles

  1. R.E. Dougherty, T. Randolph, T.-Y. Chen, J. Erickson, M. Ferland, D. Komm, J. Liu, T. Ng, S. Sandu, M. Shindler, E. Talmage, and T. Zeume. A Survey of Undergraduate Theory of Computation Curricula in the United States. In: SIGCSE Virtual 2024.
  2. L. Kari and T. Ng. Descriptional Complexity of Semi-Simple Splicing Systems. In: Developments in Language Theory (DLT 2020), LNCS 12086, 150–163.
  3. T. Ng, P. Ochem, N. Rampersad, and J. Shallit. New results on pseudosquare avoidance. In: WORDS 2019: Combinatorics on Words, LNCS 11682, 264–274.
  4. L. Kari and T. Ng. State Complexity of Simple Splicing. In: Descriptional Complexity of Formal Systems (DCFS 2019), LNCS 11612, 197–209.
  5. L. Kari and T. Ng. State Complexity of Pseudocatenation. In: Language and Automata Theory and Applications (LATA 2019), LNCS 11417, 203–214.
  6. Y.-S. Han, S.-K. Ko, T. Ng, and K. Salomaa. Closest Substring Problems for Regular Languages. In: Developments in Language Theory (DLT 2018), LNCS 11088, 392–403.
  7. S.K. Enaganti, L. Kari, T. Ng, and Z. Wang. Word blending in formal languages: The Brangelina effect. In: Unconventional Computation and Natural Computation (UCNC 2018), LNCS 10867, 72–85.
  8. T. Ng, D. Rappaport, and K. Salomaa. Relative Prefix Distance Between Languages. In: Developments in Language Theory (DLT 2017), LNCS 10396, 284–295.
  9. T. Ng, D. Rappaport, and K. Salomaa. State Complexity of Suffix Distance. In: Descriptional Complexity of Formal Systems (DCFS 2017), LNCS 10316, 287–298.
  10. Y.-S. Han, S.-K. Ko, T. Ng, and K. Salomaa. Consensus String Problem for Multiple Regular Languages. In: Language and Automata Theory and Applications (LATA 2017), LNCS 10168, 196–207.
  11. D.-J. Cho, Y.-S. Han, T. Ng, and K. Salomaa. Outfix-Guided Insertion. In: Developments in Language Theory (DLT 2016), LNCS 9840, 102–113.
  12. T. Ng. Prefix Distance Between Regular Languages. In: Implementation and Applications of Automata (CIAA 2016), LNCS 9705, 224–235.
  13. T. Ng, D. Rappaport, and K. Salomaa. State Complexity of Prefix Distance of Subregular Languages. In: Descriptional Complexity of Formal Systems (DCFS 2016), LNCS 9777, 192–204.
  14. D.-J. Cho, Y.-S. Han, T. Ng, and K. Salomaa. Pseudoknot-Generating Operation. In: SOFSEM 2016: Theory and Practice of Computer Science, LNCS 9587, 241–252.
  15. T. Ng, D. Rappaport, and K. Salomaa. State Complexity of Prefix Distance. In: Implementation and Applications of Automata (CIAA 2015), LNCS 9223, 238–249.
  16. T. Ng, D. Rappaport, and K. Salomaa. State Complexity of Neighbourhoods and Approximate Pattern Matching. In: Developments in Language Theory (DLT 2015), LNCS 9168, 389–400.
  17. T. Ng, D. Rappaport, and K. Salomaa. Quasi-distances and Weighted Finite Automata. In: Descriptional Complexity of Formal Systems (DCFS 2015), LNCS 9118, 209–219.

Non-refereed articles

  1. T. Ng, D. Rappaport, and K. Salomaa. Quasi-Distances and Weighted Finite Automata. In: The Role of Theory in Computer Science: Essays Dedicated to Janusz Brzozowski. World Scientific, 2017, 135–151.
  2. T. Ng, D. Rappaport, and K. Salomaa. Descriptional Complexity of Error Detection. In: Emergent Computation: A Festschrift for Selim G. Akl. Springer, 2017, 101–119.

Service

Miscellaneous

Keeping the tradition of academics leaving miscellaneous notes buried on their webpages alive.

  1. A coffee post ()
  2. Restaurant notes ()
  3. Simple recursive structures with Python ()
  4. About lecture notes ()
  5. CMSC 28000 Winter 2021 Playlist ()

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