Results 41 to 50 of about 103,519 (218)

Shape Derivatives of the Eigenvalues of the De Rham Complex for Lipschitz Deformations and Variable Coefficients: Part I

Mathematical Methods in the Applied Sciences, EarlyView.
ABSTRACT We study eigenvalue problems for the de Rham complex on varying three‐dimensional domains. Our analysis includes the Helmholtz equation as well as the Maxwell system with mixed boundary conditions and non‐constant coefficients. We provide Hadamard‐type formulas for the shape derivatives under weak regularity assumptions on the domain and its ...
Pier Domenico Lamberti, Dirk Pauly, Michele Zaccaron   +2 more
wiley   +1 more source

Asymptotics for the Spectrum of the Laplacian in Thin Bars with Varying Cross Sections

Mathematical Methods in the Applied Sciences, EarlyView.
ABSTRACT We consider spectral problems for the Laplace operator in 3D rod structures with a small cross section of diameter O(ε)$$ O\left(\varepsilon \right) $$, ε$$ \varepsilon $$ being a positive parameter. The boundary conditions are Dirichlet (Neumann, respectively) on the bases of this structure, and Neumann on the lateral boundary.
Pablo Benavent‐Ocejo, Delfina Gómez, Maria‐Eugenia Pérez‐Martínez   +2 more
wiley   +1 more source

Quasi-spectral decomposition of the heat potential

Electronic Journal of Differential Equations, 2016
In this article, by multiplying of the unitary operator $$ (Pf)(x,t)=f(x,T-t),\quad 0\leq t\leq T, $$ the heat potential turns into a self-adjoint operator.
Tynysbek Sh. Kal'menov, Gaukhar D. Arepova   +1 more
doaj  

The Linearized Inverse Boundary Value Problem in Strain Gradient Elasticity

Mathematical Methods in the Applied Sciences, EarlyView.
ABSTRACT In this paper we study the linearized version of the strain gradient elasticity equation in ℝ2$$ {\mathbb{R}}^2 $$ with constant coefficients and we prove that one can determine the two Lamé coefficients λ,μ$$ \lambda, \mu $$ as well as the internal strain gradient parameter g$$ g $$, as indicated by Mindlin in his revolutionary papers in 1963–
Antonios Katsampakos, Antonios Charalambopoulos   +1 more
wiley   +1 more source

2×2 operator matrix with real parameter and its spectrum [PDF]

E3S Web of Conferences
In the present paper we consider a linear bounded self-adjoint 2×2 block operator matrix Aμ (so called generalized Friedrichs model) with real parameter μ ∈ R.
Dilmurodov Elyor B., Tosheva Nargiza A., Turayeva Nabiya A., Karamatov Bolatbek T., Shokirova Durdona Sh.   +4 more
doaj   +1 more source

On the difference of spectral projections [PDF]

, 2015
For a semibounded self-adjoint operator $ T $ and a compact self-adjoint operator $ S $ acting on a complex separable Hilbert space of infinite dimension, we study the difference $ D(\lambda) := E_{(-\infty, \lambda)}(T+S) - E_{(-\infty, \lambda)}(T), \,
Uebersohn, Christoph
core  

Unbounded Products of Operators and Connections to Dirac-Type Operators

, 2013
Let $A$ and $B$ be two densely defined unbounded closeable operators in a Hilbert space such that their unbounded operator products $AB$ and $BA$ are also densely defined.
Gustafson, Karl, Mortad, Mohammed Hichem
core   +1 more source

Computing Bonds Between Formal Contexts

Mathematical Methods in the Applied Sciences, EarlyView.
ABSTRACT The notion of bond was introduced as a technique to aggregate information from multiple datasets without modifying the information already present in each of the datasets. This notion has been extended to several fuzzy frameworks, including the residuated lattice setting, which we also consider in this paper.
Roberto G. Aragón, Jesús Medina, Samuel Molina‐Ruiz   +2 more
wiley   +1 more source

Survey on differential estimators for 3d point clouds

Computer Graphics Forum, EarlyView.
Abstract Recent advancements in 3D scanning technologies, including LiDAR and photogrammetry, have enabled the precise digital replication of real‐world objects. These methods are widely used in fields such as GIS, robotics, and cultural heritage. However, the point clouds generated by such scans are often noisy and unstructured, posing challenges for ...
Léo Arnal–Anger, Thibault Lejemble, David Coeurjolly, Loïc Barthe, Nicolas Mellado   +4 more
wiley   +1 more source

Spectral analysis for the exceptional Xm-Jacobi equation

Electronic Journal of Differential Equations, 2015
We provide the mathematical foundation for the $X_m$-Jacobi spectral theory. Namely, we present a self-adjoint operator associated to the differential expression with the exceptional $X_m$-Jacobi orthogonal polynomials as eigenfunctions.
Constanze Liaw, Lance Littlejohn, Jessica Stewart Kelly   +2 more
doaj