Results 1 to 10 of about 17,908 (220)
A Method for Mounting Space Telescope Optical Systems Based on the Sensitivity Matrix of Intrinsic Coefficients. [PDF]
Sensors (Basel)Aperture space telescopes are widely used in space debris size information detection and celestial body detection work. For the problem of limited space inside the optical system of large aperture telescopes, a space telescope mounting method based on ...
Hou H, Ding H, Dong K, Cao G, Wang B.
europepmc +2 more sources
A method of generating a random optical field using the Karhunen-Loeve expansion to simulate atmospheric turbulence [PDF]
Компьютерная оптика, 2020 It is proposed to use the random field generation in the numerical simulation of the propagation of radiation through a random medium using method based on the Karhunen–Loeve expansion with various types of correlation operators to describe turbulence ...
Svetlana Khonina +2 more
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Comparison of Direct and Adjoint k and α-Eigenfunctions
Journal of Nuclear Engineering, 2021 Modal expansions based on k-eigenvalues and α-eigenvalues are commonly used in order to investigate the reactor behaviour, each with a distinct point of view: the former is related to fission generations, whereas the latter is related to time. Well-known
Vito Vitali +4 more
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An estimation of the eigenfunctions of periodic Sturm-Liouville problems
Arab Journal of Basic and Applied Sciences, 2021 In this paper, the numerical estimations for the eigenfunctions corresponding to the eigenvalues of Sturm-Liouville problem with periodic and semi-periodic boundary conditions are considered.
Seza Dinibutun
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The quantization of gravity: The quantization of the full Einstein equations [PDF]
Symmetry 15, 1599, 2023, 2023 We quantized the full Einstein equations in a globally hyperbolic spacetime $N=N^{n+1}$, $n\ge 3$, and found solutions of the resulting hyperbolic equation in a fiber bundle $E$ which can be expressed as a product of spatial eigenfunctions (eigendistributions) and temporal eigenfunctions.
arxiv +1 more source
Concentration of symmetric eigenfunctions [PDF]
Nonlinear Analysis: Theory, Methods & Applications, 2010 8 ...
Azagra Rueda, Daniel +1 more
openaire +5 more sources
AIMS Mathematics, 2022 The existence of solutions for a Sturm-Liouville boundary value problem of a nonlinear differential inclusion with nonlocal integral condition is studied. The maximal and minimal solutions will be studied.
Ahmed M.A. El-Sayed +2 more
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Solvability of Mixed Problems for a Fourth-Order Equation with Involution and Fractional Derivative
Fractal and Fractional, 2023 In the present work, two-dimensional mixed problems with the Caputo fractional order differential operator are studied using the Fourier method of separation of variables.
Mokhtar Kirane, Abdissalam A. Sarsenbi
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Mathematics, 2020 The history of boundary value problems for differential equations starts with the well-known studies of D. Bernoulli, J. D’Alambert, C. Sturm, J. Liouville, L. Euler, G. Birkhoff and V. Steklov.
Oktay Sh. Mukhtarov, Merve Yücel
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Variational characterizations for eigenfunctions of analytic self-adjoint operator functions [PDF]
Opuscula Mathematica, 2013 In this paper we consider Rellich's diagonalization theorem for analytic self-adjoint operator functions and investigate variational principles for their eigenfunctions and interlacing statements.
Georgios Katsouleas, John Maroulas
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