Results 1 to 10 of about 159,843 (190)

The Ellipsoid Factor for quantification of rods, plates and intermediate forms in 3D geometries [PDF]

Frontiers in Endocrinology, 2015
The Ellipsoid Factor (EF) is a method for the local determination of the rod- or plate-like nature of porous or spongy continua. EF at a point within a 3D structure is defined as the difference in axis ratios of the greatest ellipsoid which fits inside ...
Michael eDoube
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Functional Löwner Ellipsoids [PDF]

The Journal of Geometric Analysis, 2021
We extend the notion of the smallest volume ellipsoid containing a convex body in~$\mathbb{R}^{d}$ to the setting of logarithmically concave functions. We consider a vast class of logarithmically concave functions whose superlevel sets are concentric ellipsoids.
Ivanov, Grigory, Tsiutsiurupa, Igor
openaire   +3 more sources

Complexes of ellipsoids with indicatrices of coordinate vectors in the form of surfaces

Дифференциальная геометрия многообразий фигур, 2021
The study continues in a three-dimensional affine space of complexes of three-parameter families of ellipsoids, considered earlier in a number of works by the author.
M.V. Kretov
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Determination of coordinates of the earthquake hypocenter by the method of circles

Вестник Дагестанского государственного технического университета: Технические науки, 2021
Objective. The aim of the study is to develop a method for determining the coordinates of the earthquake hypocenter using various combinations of second and fourth order figures as a geo-locus of the hypocenter position points.Method.
G. K. Aslanov, T. G. Aslanov
doaj   +1 more source

Accurate Algorithms for Spatial Operations on the Spheroid in a Spatial Database Management System

Applied Sciences, 2021
Some of the most powerful spatial analysis software solutions (Oracle, Google Earth Engine, PostgreSQL + PostGIS, etc.) are currently performing geometric calculations directly on the ellipsoid (a quadratic surface that models the earth shape), with a ...
José Carlos Martínez-Llario, Sergio Baselga, Eloína Coll   +2 more
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Orlicz–Legendre Ellipsoids [PDF]

The Journal of Geometric Analysis, 2015
The Orlicz-Legendre ellipsoids, which are in the framework of emerging dual Orlicz Brunn-Minkowski theory, are introduced for the first time. They are in some sense dual to the recently found Orlicz-John ellipsoids, and have largely generalized the classical Legendre ellipsoid of inertia.
Zou, Du, Xiong, Ge
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Functional John ellipsoids [PDF]

Journal of Functional Analysis, 2022
Clean ...
Grigory Ivanov, Márton Naszódi
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Derivation of closed-form ellipsoidal X-ray mirror shapes from Fermat's principle

Journal of Synchrotron Radiation, 2022
Ellipsoidal and plane-elliptical surfaces are widely used as reflective, point-to-point focusing elements in many optical systems, including X-ray optics.
Kenneth A. Goldberg
doaj   +1 more source

Gravity data reduction, Bouguer anomaly, and gravity disturbance

Геофизический журнал, 2023
Each point on the earth has a gravity and gravity potential value. Surfaces formed by connecting points with equal gravity potential values are called equipotential surfaces or level surfaces.
Yi. Nazan
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High Fluid Velocity and Narrow Channels Enhance the Influences of Particle Shape on Colloid Retention in Saturated Groundwater Systems Under Favorable Deposition Conditions

Frontiers in Water, 2021
Many particulate pollutants in the environment exist in non-spherical shape, but the influences of particle shape on pollutant migration and removal in groundwater systems are not well-understood.
Ke Li, Huilian Ma
doaj   +1 more source