Research

Publications

Naomi Graham, Nicholas Richardson, Michael P. Friedlander, and Joel Saylor. Tracing Sedimentary Origins in Multivariate Geochronology via Constrained Tensor Factorization. Mathematical Geosciences, Feb. 2025. PDF code web tool

Michael L. Waite and Nicholas Richardson. Potential Vorticity Generation in Breaking Gravity Waves. Atmosphere, 14(5):881, 2023. PDF

Nicholas Richardson, Hayden Schaeffer, and Giang Tran. SRMD: Sparse Random Mode Decomposition. Communications on Applied Mathematics and Computation, 2023. PDF

Lam Si Tung Ho, Nicholas Richardson, and Giang Tran. Adaptive group Lasso neural network models for functions of few variables and time-dependent data. Sampling Theory, Signal Processing, and Data Analysis, 21(2):28, 2023.

Nicholas Richardson. A Sparse Random Feature Model for Signal Decomposition. UWSpace, 2022. (Master’s Thesis). link PDF

In progress

Joel Saylor, Nicholas Richardson, Naomi Graham, Robert Lee, and Michael P. Friedlander. Tracking cu-fertile sediment sources via multivariate petrochronological mixture modelling of detrital zircons. (in review).

Nicholas Richardson, Noah Marusenko, and Michael P. Friedlander. Multiple Scale Methods for Optimization of Discretized Continuous Functions. (in preparation).

Presentations

Conferences

30 Jul 2025: BlockTensorDecomposition.jl: An Optimization Framework for Constrained Tensor Factorization, Joint SIAM/CAIMS Annual Meetings 2025, Montréal, QC. slides

14 Jul 2025: Unsupervised Signal Demixing with Tensor Factorization, Vision and Learning Workshop at ICML 2025, Vancouver, BC. poster

02 Dec 2024: Density Separation with Tensor Factorization, 2024 CMS Winter Meeting, Richmond, BC. slides

20 Oct 2024: Density Separation with Tensor Factorization, 2024 INFORMS Annual Meeting, Seattle, WA. slides

21 Sep 2024: Density Separation with Tensor Factorization, West Coast Optimization Meeting 2024, Vancouver, BC. slides

08 Jul 2024: Density Separation with Tensor Factorization, 2024 SIAM Annual Meeting, Spokane, WA. slides

14 Oct 2023: Non-negative Tensor Decompositions for Unsupervised Learning, 4th Biennial Meeting of SIAM Pacific Northwest Section, Bellingham, WA. slides

01 Jul 2021: Sparse Random Wavelet Representation & Decomposition, Canadian Applied and Industrial Mathematics Society (CAIMS), Waterloo, ON. Runner up in annual poster competition poster slides website

Other Talks

11 Apr 2025: Discretizing Constraints at Multiple Scales, 2025 Institute of Applied Math Retreat, Vancouver, BC. slides

04 Mar 2025: Learning Gaussian Mixtures Using the Wasserstein-Fisher-Rao Gradient Flow, Machine Learning Reading Group, Vancouver, BC. slides original paper

18 Feb 2025: Mathematics of Music: Connections from harmonics to tuning, Math Graduate Seminar, Vancouver BC. notes

15 Apr 2024: Approximate Matrix Rank, 2024 Institute of Applied Math Retreat, Vancouver, BC. slides

10 Oct 2023: Tensor Decompositions, Optimization & Applications, Math Graduate Seminar, Vancouver BC.

Notes

Course notes, projects, and other write-ups.

Expected Error and Residuals for Least Squares with Gaussian Matrices University of British Columbia MATH 555: High Dimensional Probability, final project. 13 April 2023.

Low-rank Decompositions of Musical STFT Tensors University of British Columbia MATH 605D: Tensor Decompositions, final project. 15 December 2022.

The Water Bottle Resonator University of Waterloo SYDE 750: Acoustics, final project. 8 April 2021. slides code

Nyquist-Shannon Sampling Theorem and Whittaker-Shannon Interpolation University of Waterloo AMATH 731: Functional Analysis, final presentation. 9 December 2020.