333 research outputs found
Recovering Differential Operators on Spatial Networks
We give a short review of results on inverse spectral problems for ordinary
differential operators on a spatial networks (geometrical graphs). We pay the
main attention to the most important nonlinear inverse problems of recovering
coefficients of differential equations from spectral characteristics provided
that the structure of the graph is known a priori. In the first half of the
review we provide results related to inverse Sturm-Liouville problems on
arbitrary compact graphs. Further, results on inverse problems for arbitrary
order differential operators on compact graphs are presented. At the end we
provide the main results on inverse problems on noncompact graphs.Comment: 35 pages, 4 figure
Recovering Differential Operators with Nonseparated Boundary Conditions in the Central Symmetric Case
Inverse spectral problems for Sturm-Liouville operators on a finite interval
with non-separated boundary conditions are studied in the central symmetric
case, when the potential is symmetric with respect to the middle of the
interval. We discuss statements of the problems, provide algorithms for their
solutions along with necessary and sufficient conditions for the solvability of
the inverse problems considered
On Quasi-periodic Differential Pencils with Jump Conditions Inside the Interval
Non-self-adjoint second-order differential pencils on a finite interval with
non-separated quasi-periodic boundary conditions and jump conditions are
studied. We establish properties of spectral characteristics and investigate
the inverse spectral problem of recovering the operator from its spectral data.
For this inverse problem we prove the corresponding uniqueness theorem and
provide an algorithm for constructing its solution.Comment: 7 page
Recovering First Order Integro-Differential Operators from Spectral Data
First order integro-differential operators on a finite interval are studied.
Properties of spectral characteristic are established, and the uniqueness
theorem is proved for the inverse problem of recovering operators from their
spectral data.Comment: 5 pages. arXiv admin note: text overlap with arXiv:1702.0078
Inverse Spectral Problems for Sturm-Liouville Operators on Hedgehog-type Graphs with General Matching Conditions
Boundary value problems on hedgehog-type graphs for Sturm-Liouville
differential operators with general matching conditions are studied. We
investigate inverse spectral problems of recovering the coefficients of the
differential equation from the spectral data. For this inverse problem we prove
a uniqueness theorem and provide a procedure for constructing its solution.Comment: 7 page
Recovering Variable Order Differential Operators with Regular Singularities on Graphs
We study inverse spectral problems for ordinary differential equations with
regular singularities on compact star-type graphs when differential equations
have different orders on diferent edges. As the main spectral characteristics
we introduce and study the so-called Weyl-type matrices which are
generalizations of the Weyl function for the classical Sturm-Liouville
operator. We provide a procedure for constructing the solution of the inverse
problem and prove its uniqueness.Comment: 10 pages. arXiv admin note: substantial text overlap with
arXiv:1410.2007; text overlap with arXiv:1309.5360 by other author
Inverse Problems for Systems of Variable Order Differential Equations with Singularities on Spatial Networks
Variable order differential equations with non-integrable singularities are
considered on spatial networks. Properties of the spectrum are established, and
the solution of the inverse spectral problem is obtained.Comment: 11 pages. arXiv admin note: substantial text overlap with
arXiv:1503.0175
File mapping Rule-based DBMS and Natural Language Processing
This paper describes the system of storage, extract and processing of
information structured similarly to the natural language. For recursive
inference the system uses the rules having the same representation, as the
data. The environment of storage of information is provided with the File
Mapping (SHM) mechanism of operating system. In the paper the main principles
of construction of dynamic data structure and language for record of the
inference rules are stated; the features of available implementation are
considered and the description of the application realizing semantic
information retrieval on the natural language is given.Comment: 17 pages, 3 figure
Recovering Dirac systems with singularities in interior points
We study the non-selfadjoint Dirac system on a finite interval having
non-integrable regular singularities in interior points with additional
matching conditions at these points. Properties of spectral characteristics are
established, and the inverse spectral problem is investigated. We provide a
constructive procedure for the solution of the inverse problem, and prove its
uniqueness. Moreover, necessary and sufficient conditions for the global
solvability of this nonlinear inverse problem are obtained.Comment: 22 page
On the dynamics of solitary wave solutions supported by the model of mutually penetrating continua
The model we deal with is the mathematical model for mutually penetrating
continua one of which is the carrying medium obeying the wave equation whereas
the other one is the oscillating inclusion described by the equation for
oscillators. These equations of motion are closed by the cubic constitutive
equation for the carrying medium. Studying the wave solutions we reduce this
model to a plane dynamical system of Hamiltonian type. This allows us to derive
the relation describing the homoclinic trajectory going through the origin and
obtain the solitary wave with infinite support. Moreover, there exist a
limiting solitary wave with finite support, i.e. compacton. To model the
solitary waves dynamics, we construct the three level finite-difference
numerical scheme and study its stability. We are interested in the interaction
of the pair of solitary waves. It turns out that the collisions of solitary
waves have non-elastic character but the shapes of waves after collisions are
preserved.Comment: "Dynamical systems: Mechatronics and Life Sciences", Vol.2, Eds.
J.Awrejcewicz et al., 2015 - PP. 453-460, 13-th International conference
Dynamical Systems - Theory and Applications 7-10 December 2015, Lodz, Polan
- …