Results 21 to 30 of about 22,150,955 (299)
Modelling of ionospheric time delays based on adjusted spherical harmonic analysis
Aviation, 2016 The ionosphere is the region of the upper atmosphere and the study of the upper atmosphere has a significant role in monitoring, modeling and forecasting for satellite based navigation services.
J R K Kumar Dabbakuti +2 more
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IEEE Access, 2019 Recently, a modeling method for head-related transfer functions (HRTFs) in the spatial domain is proposed based on spherical wavelets. Because spherical wavelets are local functions on the sphere, HRTF local features can be efficiently represented by ...
Huaping Liu, Yong Fang, Qinghua Huang
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Spherical harmonic analysis in the presence of high harmonics.
Journal of geomagnetism and geoelectricity, 1981 Spherical harmonic analysis of the geomagnetic field is usually done by using the method of least squares in conjunction with a truncated spherical harmonic series. The results obtained are very dependent on the weighting used, the distribution of the observational data and the degree of truncation, especially for shallow sources that give rise to high
ALLDREDGE, L. R., KAWASAKI, Koji
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Discrete spherical means of directional derivatives and Veronese maps [PDF]
, 2011 We describe and study geometric properties of discrete circular and spherical means of directional derivatives of functions, as well as discrete approximations of higher order differential operators.
Alexander Belyaev +8 more
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3D time series analysis of cell shape using Laplacian approaches [PDF]
, 2013 Background: Fundamental cellular processes such as cell movement, division or food uptake critically depend on cells being able to change shape. Fast acquisition of three-dimensional image time series has now become possible, but we lack efficient tools
Stephens, Len R. +7 more
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Magnetospheric contributions to geomagnetic daily variations [PDF]
Annales Geophysicae, 1996 The contribution of magnetospheric current systems to geomagnetic daily variations is analyzed by means of a spherical harmonic analysis (SHA) using elementary models as well as the Tsyganenko model of the magnetosphere.
N. Olsen
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Dirichlet and Neumann Boundary Value Problems for Dunkl Polyharmonic Equations
Mathematics, 2023 Dunkl operators are a family of commuting differential–difference operators associated with a finite reflection group. These operators play a key role in the area of harmonic analysis and theory of spherical functions.
Hongfen Yuan, Valery Karachik
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RECOVERING THE LAPLACIAN FROM CENTERED MEANS ON BALLS AND SPHERES OF FIXED RADIUS
Проблемы анализа, 2023 Various issues related to restrictions on radii in meanvalue formulas are well-known in the theory of harmonic functions. In particular, using the Brown-Schreiber-Taylor theorem on spectral synthesis for motion-invariant subspaces in 𝐶(R^𝑛), one can ...
N. P. Volchkova, Vit. V. Volchkov
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Harmonic analysis on certain spherical varieties
Journal of the European Mathematical Society, 2023 Braverman and Kazhdan proposed a conjecture, later refined by Ngô and broadened to the framework of spherical varieties by Sakellaridis, that asserts that affine spherical varieties admit Schwartz spaces, Fourier transforms, and Poisson summation formulae. The first author in joint work with B.
Getz, Jayce R. +2 more
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Research on MRI Gradient Coil Magnetic Field Induced Eddy Current Method
Zhongguo yiliao qixie zazhiAfter the production of the gradient coil of the magnetic resonance imaging system, electromagnetic field testing is required to verify whether the assembly accuracy meets the electromagnetic field requirements.
Xiaotao ZHANG +5 more
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