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Statistical Shape Modeling (SSM) is a quantitative method for analyzing morphological variations in anatomical structures. These analyses often necessitate building models on targeted anatomical regions of interest to focus on specific…

Computer Vision and Pattern Recognition · Computer Science 2024-01-02 Hong Xu , Alan Morris , Shireen Y. Elhabian

We consider the motion of a particle on a surface which is a small perturbation of the standard sphere. One may qualitatively describe the motion by means of a precessing great circle of the sphere. The observation is employed to derive a…

Mathematical Physics · Physics 2007-05-23 V. L. Golo , D. O. Sinitsyn

We consider a simply supported plate with constant thickness, defined on an unknown multiply connected domain. We optimize its shape according to some given performance functional. Our method is of fixed domain type, easy to be implemented,…

Optimization and Control · Mathematics 2019-09-13 Dan Tiba , Cornel Marius Murea

We study the conformal type of surfaces spread over the sphere via random quasiconformal maps. Constructing a random Beltrami coefficient on the complex plane, we obtain a locally quasiconformal homeomorphism with prescribed dilatation that…

Complex Variables · Mathematics 2026-03-18 Michael Iofin

We investigate the reliability of mass estimators based on the observable velocity dispersion and half-light radius $R_\mathrm{h}$ for dispersion-supported galaxies. We show how to extend them to flattened systems and provide simple…

Astrophysics of Galaxies · Physics 2016-10-19 Jason L. Sanders , N. Wyn Evans

We propose estimators for the parameters of the Linnik L$(\alpha,\gamma)$ distribution. The estimators are derived from the moments of the log-transformed Linnik distributed random variable, and are shown to be asymptotically unbiased. The…

Methodology · Statistics 2017-03-27 Dexter Cahoy

For a sample of absolutely bounded i.i.d. random variables with a continuous density the cumulative distribution function of the sample variance is represented by a univariate integral over a Fourier series. If the density is a polynomial…

Statistics Theory · Mathematics 2008-10-10 T. Royen

The study of random surfaces, especially in the asymptotics of large genus, has been of increasing interest in recent years. Many geometrical questions have analogous formulations in the theory of random graphs with a large number of…

Geometric Topology · Mathematics 2026-01-05 Joffrey Mathien

By a real alphabeta-geometry we mean a four-dimensional manifold M equipped with a neutral metric h such that (M,h) admits both an integrable distribution of alpha-planes and an integrable distribution of beta-planes. We obtain a local…

Differential Geometry · Mathematics 2013-01-01 Peter R. Law , Yasuo Matsushita

Parameter estimation is one of the most important tasks in statistics, and is key to helping people understand the distribution behind a sample of observations. Traditionally parameter estimation is done either by closed-form solutions…

Machine Learning · Computer Science 2024-03-04 Xiaoxin Yin , David S. Yin

A method for drawing random samples of unit vectors $x$ in $R^p$ with density proportional to $x^TAx$ where $A$ is a symmetric, positive definite matrix. Includes an R function which implements the method.

Computation · Statistics 2018-12-31 Richard Arnold

Most of the work on checking spherical symmetry assumptions on the distribution of the $p$-dimensional random vector $Y$ has its focus on statistical tests for the null hypothesis of exact spherical symmetry. In this paper, we take a…

Methodology · Statistics 2026-01-26 Lujia Bai , Holger Dette

We consider polygonal tilings of certain regions and use these to give intuitive definitions of tiling-based perimeter and area. We apply these definitions to rhombic tilings of Elnitsky polygons, computing sharp bounds and average values…

Combinatorics · Mathematics 2020-04-30 Bridget Eileen Tenner

We propose a method to measure the subdiffusion parameter $\alpha$ and subdiffusion coefficient $D_{\alpha}$ which are defined by means of the relation $<x^2> =\frac{2D_\alpha} {\Gamma(1+\alpha)} t^\alpha$ where $<x^2>$ denotes a mean…

Statistical Mechanics · Physics 2009-11-11 T. Kosztolowicz , K. Dworecki , St. Mrowczynski

We prove new $L^p$- $L^q$ estimates for averages over dilates of the circle with respect to $\alpha$-dimensional fractal measure, which unify different types of maximal estimates for the circular average. Our results are consequences of…

Classical Analysis and ODEs · Mathematics 2022-08-08 Seheon Ham , Hyerim Ko , Sanghyuk Lee

The parameterization of open and closed anatomical surfaces is of fundamental importance in many biomedical applications. Spherical harmonics, a set of basis functions defined on the unit sphere, are widely used for anatomical shape…

Computational Geometry · Computer Science 2022-06-30 Gary P. T. Choi , Amita Giri , Lalan Kumar

The percolation threshold for flow or conduction through voids surrounding randomly placed spheres is rigorously calculated. With large scale Monte Carlo simulations, we give a rigorous continuum treatment to the geometry of the…

Disordered Systems and Neural Networks · Physics 2012-08-02 D. J. Priour

Series representations consisting of spherical harmonics are obtained for characteristic exponents and probability density functions of multivariate stable distributions under various conditions. A esult potentially applicable in a…

Probability · Mathematics 2021-10-18 Zhiyi Chi

In areas such as kernel smoothing and non-parametric regression there is emphasis on smooth interpolation and smooth statistical models. Splines are known to have optimal smoothness properties in one and higher dimensions. It is shown, with…

Computation · Statistics 2008-09-29 Ron A. Bates , Hugo Maruri-Aguilar , Henry P. Wynn

An angular distribution of received signals has a significant impact on their spectral and correlational properties. Most of angular dispersion models do not consider antenna patterns. The developed procedure for determining the propagation…

Information Theory · Computer Science 2025-03-25 Cezary Ziolkowski , Jan M. Kelner , Leszek Nowosielski , Marian Wnuk