collaborators

8 papers

q-bio.QM2026

A curvature-based criterion for harmonic circadian waveforms

Yusuke Yamada, Yutaro Kabata, Ryoya Fukasaku +1

Experimental and theoretical studies of circadian rhythms have focused largely on the period, on mutants that alter it and on phase shifts, and this focus has driven the identifica…

math.ST2026

At least seven modes in a heteroscedastic three-component bivariate Gaussian mixture

Yutaro Kabata, Hirotaka Matsumoto, Akifumi Okuno

A Gaussian mixture density can have more modes than components. It has been conjectured that the maximum number of modes of a -variate -component Gaussian mixture density is…

math.ST2026

On Mixtures of Three Homoscedastic Gaussian Densities: An Unconditional Sharper Bound on the Number of Modes

Akifumi Okuno, Yutaro Kabata

It is known that a mixture of three homoscedastic multivariate Gaussian densities whose centers form an equilateral triangle can have four modes, owing to the emergence of a ``ghos…

math.DG2026

Shapes of light: singularities of slant functions and the Gauss map of a surface

Shuhei Honda, Yutaro Kabata

The slant function on a regular surface in three-space, introduced by Koenderink, is the inner product of a fixed light direction with the unit normal; under the standard Lambertia…

stat.ML2025

Algebraic Approach to Ridge-Regularized Mean Squared Error Minimization in Minimal ReLU Neural Network

Ryoya Fukasaku, Yutaro Kabata, Akifumi Okuno

This paper investigates a perceptron, a simple neural network model, with ReLU activation and a ridge-regularized mean squared error (RR-MSE). Our approach leverages the fact that…

math.DG2025

Visualization of curvature on curve and surface by tangential angle parametrization

Yutaro Kabata, Shigeki Matsutani, Yuta Ogata

We propose a unified method to visualize curvature on planar curves and surfaces of revolution using the tangential angle parameter. For plane curves, placing markers at equal incr…