4 papers
A Provably-Correct and Robust Convex Model for Smooth Separable NMF
Junjun Pan, Valentin Leplat, Michael Ng +1
Nonnegative matrix factorization (NMF) is a linear dimensionality reduction technique for nonnegative data, with applications such as hyperspectral unmixing and topic modeling. NMF…
Hermitian Quaternion Toeplitz Matrices by Quaternion-valued Generating Functions
Xue-lei Lin, Michael K. Ng, Junjun Pan
In this paper, we study Hermitian quaternion Toeplitz matrices generated by quaternion-valued functions. We show that such generating function must be the sum of a real-valued func…
QuatIca: Advanced Numerical Linear Algebra and Optimization for Quaternionic Matrices in Python
Valentin Leplat, Salman Ahmadi-Asl, Junjun Pan +2
Quaternion-valued representations provide a convenient way to model coupled multi-channel signals (e.g., RGB imagery, polarization data, vector fields, and multi-detector time seri…
Non-Negative Reduced Biquaternion Matrix Factorization with Applications in Color Face Recognition
Jifei Miao, Junjun Pan, Michael K. Ng
Reduced biquaternion (RB), as a four-dimensional algebra highly suitable for representing color pixels, has recently garnered significant attention from numerous scholars. In this…