Skocz do pozycji: 1.

Tytuł:

Determination of eigenvalues and eigenvectors by means of iterations of subspaces

Autorzy:

Pokrzywa, Andrzej

Powiązania:

https://bibliotekanauki.pl/articles/747613.pdf

Data publikacji:

1985

Wydawca:

Polskie Towarzystwo Matematyczne

Tematy:

Eigenvalues, eigenvectors
Singular values

Opis:

.
Let A be a compact linear operator in a Banach space X. The author investigates the iterations of a given subspace M of X. He formulates sufficient conditions for the convergence (in the sense of the gap between subspaces). This result is applied to the study of spectra of operators.

Źródło:

Mathematica Applicanda; 1985, 12, 24
1730-2668
2299-4009

Pojawia się w:

Mathematica Applicanda

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 2.

Tytuł:

Convergence of formal solutions of first order singular nonlinear partial differential equations in the complex domain

Autorzy:

Miyake, Masatake
Shirai, Akira

Powiązania:

https://bibliotekanauki.pl/articles/1207974.pdf

Data publikacji:

2000

Wydawca:

Polska Akademia Nauk. Instytut Matematyczny PAN

Tematy:

singular equation
formal solution

Opis:

We study the convergence or divergence of formal (power series) solutions of first order nonlinear partial differential equations
   (SE) f(x,u,D_x u) = 0 with u(0)=0.
Here the function f(x,u,ξ) is defined and holomorphic in a neighbourhood of a point $(0,0,ξ^{0}) ∈ ℂ^{n}_{x} × ℂ_{u} × ℂ^{n}_{ξ} (ξ^{0} = D_{x}u(0))$ and $f(0,0,ξ^{0}) = 0$. The equation (SE) is said to be singular if f(0,0,ξ) ≡ 0 $(ξ ∈ ℂ^{n})$. The criterion of convergence of a formal solution $u(x) = ∑_{|α| ≥ 1} u_{α}x^{α}$ of (SE) is given by a generalized form of the Poincaré condition which depends on each formal solution. In the case where the formal solution diverges a precise rate of divergence or the formal Gevrey order is specified which can be interpreted in terms of the Newton polygon as in the case of linear equations but for nonlinear equations it depends on the individual formal solution.

Źródło:

Annales Polonici Mathematici; 2000, 74, 1; 215-228
0066-2216

Pojawia się w:

Annales Polonici Mathematici

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 3.

Tytuł:

Signatura of magic and Latin integer squares: isentropic clans and indexing

Autorzy:

Cameron, Ian
Rogers, Adam
Loly, Peter

Powiązania:

https://bibliotekanauki.pl/articles/729830.pdf

Data publikacji:

2013

Wydawca:

Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii

Tematy:

Shannon entropy
magic square
Latin square
singular value decomposition
singular value clan

Opis:

The 2010 study of the Shannon entropy of order nine Sudoku and Latin square matrices by Newton and DeSalvo [Proc. Roy. Soc. A 2010] is extended to natural magic and Latin squares up to order nine. We demonstrate that decimal and integer measures of the Singular Value sets, here named SV clans, are a powerful way of comparing different integer squares.
Several complete sets of magic and Latin squares are included, including the order eight Franklin subset which is of direct relevance to magic square line patterns on chess boards. While early examples suggested that lower rank specimens had lower entropy, sufficient data is presented to show that some full rank cases with low entropy possess a set of singular values separating into a dominant group with the remainder much weaker. An effective rank measure helps understand these issues.
We also introduce a new measure for integer squares based on the sum of the fourth powers of the singular values which appears to give a useful method of indexing both Latin and magic squares. This can be used to begin cataloging a "library" of magical squares.
Based on a video presentation in celebration of George Styan's 75th at LINSTAT2012 and IWMS-21 on 19 July, 2012 at Będlewo, Poland.

Źródło:

Discussiones Mathematicae Probability and Statistics; 2013, 33, 1-2; 121-149
1509-9423

Pojawia się w:

Discussiones Mathematicae Probability and Statistics

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 4.

Tytuł:

Local Toeplitz operators based on wavelets: phase space patterns for rough wavelets

Autorzy:

Nowak, Krzysztof

Powiązania:

https://bibliotekanauki.pl/articles/1287604.pdf

Data publikacji:

1996

Wydawca:

Polska Akademia Nauk. Instytut Matematyczny PAN

Tematy:

singular values
time-frequency localization

Opis:

We consider two standard group representations: one acting on functions by translations and dilations, the other by translations and modulations, and we study local Toeplitz operators based on them. Local Toeplitz operators are the averages of projection-valued functions $g ↦ P_{g,ϕ}$, where for a fixed function ϕ, $P_{g,ϕ}$ denotes the one-dimensional orthogonal projection on the function $U_gϕ$, U is a group representation and g is an element of the group. They are defined as integrals $ʃ_W P_{g,ϕ} dg$, where W is an open, relatively compact subset of a group. Our main result is a characterization of function spaces corresponding to local Toeplitz operators with pth power summable eigenvalues, 0 < p ≤ ∞.

Źródło:

Studia Mathematica; 1996, 119, 1; 37-64
0039-3223

Pojawia się w:

Studia Mathematica

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 5.

Tytuł:

Weighted weak type (1,1) estimates for oscillatory singular integrals

Autorzy:

Sato, Shuichi

Powiązania:

https://bibliotekanauki.pl/articles/1206034.pdf

Data publikacji:

2000

Wydawca:

Polska Akademia Nauk. Instytut Matematyczny PAN

Tematy:

rough operators
oscillatory singular integrals

Opis:

We consider the $A_1$-weights and prove the weighted weak type (1,1) inequalities for certain oscillatory singular integrals.

Źródło:

Studia Mathematica; 2000, 141, 1; 1-24
0039-3223

Pojawia się w:

Studia Mathematica

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 6.

Tytuł:

Strictly singular operators and the invariant subspace problem

Autorzy:

Read, C.

Powiązania:

https://bibliotekanauki.pl/articles/1217278.pdf

Data publikacji:

1999

Wydawca:

Polska Akademia Nauk. Instytut Matematyczny PAN

Tematy:

operator
invariant subspace
strictly singular

Opis:

Properties of strictly singular operators have recently become of topical interest because the work of Gowers and Maurey in [GM1] and [GM2] gives (among many other brilliant and surprising results, such as those in [G1] and [G2]) Banach spaces on which every continuous operator is of form λ I + S, where S is strictly singular. So if strictly singular operators had invariant subspaces, such spaces would have the property that all operators on them had invariant subspaces. However, in this paper we exhibit examples of strictly singular operators without nontrivial closed invariant subspaces. So, though it may be true that operators on the spaces of Gowers and Maurey have invariant subspaces, yet this cannot be because of a general result about strictly singular operators. The general assertion about strictly singular operators is false.

Źródło:

Studia Mathematica; 1999, 132, 3; 203-226
0039-3223

Pojawia się w:

Studia Mathematica

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 7.

Tytuł:

Systems of Clairaut type

Autorzy:

Izumiya, Shyuichi

Powiązania:

https://bibliotekanauki.pl/articles/967256.pdf

Data publikacji:

1993

Wydawca:

Polska Akademia Nauk. Instytut Matematyczny PAN

Tematy:

singular solutions
complete solutions
Clairaut equation

Opis:

A characterization of systems of first order differential equations with (classical) complete solutions is given. Systems with (classical) complete solutions that consist of hyperplanes are also characterized.

Źródło:

Colloquium Mathematicum; 1993, 66, 2; 219-226
0010-1354

Pojawia się w:

Colloquium Mathematicum

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 8.

Tytuł:

Singular fractional discrete-time linear systems

Autorzy:

Kaczorek, T.

Powiązania:

https://bibliotekanauki.pl/articles/206067.pdf

Data publikacji:

2011

Wydawca:

Polska Akademia Nauk. Instytut Badań Systemowych PAN

Tematy:

decomposition
singular
fractional
linear system
solution

Opis:

A new class of singular fractional linear discretetime systems is introduced. Using the Weierstrass regular pencil decomposition the solution to the state equation of singular fractional linear systems is derived. The considerations are illustrated by numerical examples.

Źródło:

Control and Cybernetics; 2011, 40, 3; 753-761
0324-8569

Pojawia się w:

Control and Cybernetics

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 9.

Tytuł:

Computation of positive realizations of SISO singular hybrid linear systems

Autorzy:

Kaczorek, T.
Sajewski, Ł.

Powiązania:

https://bibliotekanauki.pl/articles/385061.pdf

Data publikacji:

2009

Wydawca:

Sieć Badawcza Łukasiewicz - Przemysłowy Instytut Automatyki i Pomiarów

Tematy:

hybrid linear systems
singular
positive
realization

Opis:

The realization problem for 2D positive singular linear hybrid systems is formulated, as well as a method based on the state variable diagram for finding a positive realization of a given improper transfer function is proposed. Sufficient conditions for the existence of a positive realization of a given improper transfer function are established. A procedure for computation of a positive realization is proposed and illustrated by a numerical example.

Źródło:

Journal of Automation Mobile Robotics and Intelligent Systems; 2009, 3, 2; 8-13
1897-8649
2080-2145

Pojawia się w:

Journal of Automation Mobile Robotics and Intelligent Systems

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 10.

Tytuł:

Topological properties of spaces of linear operators on non-locally convex Orlicz spaces

Autorzy:

Oelke, Agnieszka

Powiązania:

https://bibliotekanauki.pl/articles/745952.pdf

Data publikacji:

2010

Wydawca:

Polskie Towarzystwo Matematyczne

Tematy:

Orlicz spaces
linear operators
singular operators

Opis:

We study the topological properties of the space \(\mathcal{L}(L^\varphi, X)\) of all continuous linear operators from an Orlicz space \(L^\varphi\) (an Orlicz function \(\varphi\) is not necessarily convex) to a Banach space \(X\). We provide the space \(\mathcal{L}(L^\varphi ,X)\) with the Banach space structure. Moreover, we examine the space \(\mathcal{L}_s (L^\varphi, X)\) of all singular operators from \(L^\varphi\) to \(X\).

Źródło:

Commentationes Mathematicae; 2010, 50, 2
0373-8299

Pojawia się w:

Commentationes Mathematicae

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 11.

Tytuł:

On \(\ell_{q}\)-strictly singular operators on variable exponent spaces

Autorzy:

Buelga, Carlos
Hernandez, Francisco L.

Powiązania:

https://bibliotekanauki.pl/articles/746291.pdf

Data publikacji:

2015

Wydawca:

Polskie Towarzystwo Matematyczne

Tematy:

Variable exponent spaces, strictly singular operators

Opis:

Strictly singular operators on variable exponent (or Nakano) function spaces \(L^{p\left(\cdot\right)}\) are characterized in terms of being \(\ell_{q}\)-strictly singular for the values \(q\) in the essential range \(R_{p\left(\cdot\right)}\) of the exponent function. This extends a result of L. Weiss [On perturbations of Fredholm operators in \(L_{p}\)-spaces, Proc. Amer. Math. Soc. 67 (1977), 287-292] for \(L^{p}\)-spaces.

Źródło:

Commentationes Mathematicae; 2015, 55, 2
0373-8299

Pojawia się w:

Commentationes Mathematicae

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 12.

Tytuł:

Metamorphoses of resonance curves in systems of coupled oscillators

Autorzy:

Kyzioł, J.
Okniński, A.

Powiązania:

https://bibliotekanauki.pl/articles/279900.pdf

Data publikacji:

2016

Wydawca:

Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej

Tematy:

coupled oscillators
amplitude profiles
singular points

Opis:

We study dynamics of two coupled periodically driven oscillators in a general case and compare it with two simplified models. Periodic steady-state solutions to these system equations are determined within the Krylov-Bogoliubov-Mitropolsky approach. Amplitude profiles are computed. These two equations, each describing a surface, define a 3D curve – intersection of these surfaces. In the present paper, we analyse metamorphoses of amplitude profiles induced by changes of control parameters in three dynamical systems studied. It is shown that changes of the dynamics occur in the vicinity of singular points of these 3D curves.

Źródło:

Journal of Theoretical and Applied Mechanics; 2016, 54, 4; 1197-1204
1429-2955

Pojawia się w:

Journal of Theoretical and Applied Mechanics

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 13.

Tytuł:

Solutions of a class of singular linear systems of difference equations. Part 1

Autorzy:

Kanan, Asmaa M.

Powiązania:

https://bibliotekanauki.pl/articles/1030103.pdf

Data publikacji:

2020

Wydawca:

Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN

Tematy:

Drazin inverse
Rank
Singular difference equations

Opis:

We extend results of Campbell, Meyer, Jr. and Rose of applications of the Drazine inverse to linear systems of differential equations with singular constant coefficients to solutions of linear systems of difference equations A x_(n+1)+B x_n= f_n ,n≥0 when A and B are m×m complex matrices and may both singular, under conditions that rank(A)=1 and trace of A is not equal zero. f_n is an arbitrary function in C^m, and x_n∈C^m. We give a new closed form for all solutions of those systems when they are tractable, using the theory of the Drazin inverse, and a matrix K∈C^(m×m).

Źródło:

World Scientific News; 2020, 143; 53-66
2392-2192

Pojawia się w:

World Scientific News

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 14.

Tytuł:

Solution of linear systems of differential equations with singular constant coefficients by the Drazin inverse of matrices

Autorzy:

Kanan, Asmaa M.
Hassan, Khadija

Powiązania:

https://bibliotekanauki.pl/articles/1046563.pdf

Data publikacji:

2019

Wydawca:

Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN

Tematy:

Drazin inverse
Index
Singular differential equations

Opis:

Let A ,B be n×n matrices of complex numbers. Let G a vector-valued function of the real variable t. A and B may both be singular, rank(A) = 1, and the trac of A is not equal zero. The linear system of differential equations Ax^' (t)+Bx(t)=G(t) is studied using the Drazin inverse A^D of A, and a new matrix K∈C^(n×n). In this paper, we obtain a new closed form for the general solution of the differential system when the system is tractable.

Źródło:

World Scientific News; 2019, 137; 229-236
2392-2192

Pojawia się w:

World Scientific News

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 15.

Tytuł:

Ondelettes et poids de Muckenhoupt

Autorzy:

Gilles Lemarié-Rieusset, Pierre

Powiązania:

https://bibliotekanauki.pl/articles/1291171.pdf

Data publikacji:

1994

Wydawca:

Polska Akademia Nauk. Instytut Matematyczny PAN

Tematy:

singular integrals
wavelets
weighted Lebesgue spaces

Opis:

We study, for a basis of Hölderian compactly supported wavelets, the boundedness and convergence of the associated projectors $P_j$ on the space $L^p(dμ)$ for some p in ]1,∞[ and some nonnegative Borel measure μ on ℝ. We show that the convergence properties are related to the $A_p$ criterion of Muckenhoupt.

Źródło:

Studia Mathematica; 1994, 108, 2; 127-147
0039-3223

Pojawia się w:

Studia Mathematica

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 16.

Tytuł:

Positive solutions to nonlinear singular second order boundary value problems

Autorzy:

Bonanno, Gabriele

Powiązania:

https://bibliotekanauki.pl/articles/1310938.pdf

Data publikacji:

1996

Wydawca:

Polska Akademia Nauk. Instytut Matematyczny PAN

Tematy:

singular boundary value problem
positive solution

Opis:

Existence theorems of positive solutions to a class of singular second order boundary value problems of the form y'' + f(x,y,y') = 0, 0 < x < 1, are established. It is not required that the function (x,y,z) → f(x,y,z) be nonincreasing in y and/or z, as is generally assumed. However, when (x,y,z) → f(x,y,z) is nonincreasing in y and z, some of O'Regan's results [J. Differential Equations 84 (1990), 228-251] are improved. The proofs of the main theorems are based on a fixed point theorem for weakly sequentially continuous operators.

Źródło:

Annales Polonici Mathematici; 1996, 64, 3; 237-251
0066-2216

Pojawia się w:

Annales Polonici Mathematici

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 17.

Tytuł:

Pontryagin Maximum Principle for coupled slow and fast systems

Autorzy:

Artstein, Z.

Powiązania:

https://bibliotekanauki.pl/articles/970920.pdf

Data publikacji:

2009

Wydawca:

Polska Akademia Nauk. Instytut Badań Systemowych PAN

Tematy:

optimal control
singular perturbations
maximum principle

Opis:

When slow and fast controlled dynamics are coupled, the variational limit, as the ratio of time scales grows, is best depicted as a trajectory in a probability measures space. The effective control is then an invariant measure on the fast state-control space. The paper presents the form of the Pontryagin Maximum Principle for this variational limit and examines its relation to the Maximum Principle of the perturbed system.

Źródło:

Control and Cybernetics; 2009, 38, 4A; 1003-1019
0324-8569

Pojawia się w:

Control and Cybernetics

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 18.

Tytuł:

On discounted LQR control problem for disturbanced singular system

Autorzy:

Yulianti, Lyra
Nazra, Admi
-, Zulakmal
Bahar, Arifah
Muhafzan, Muhafzan

Powiązania:

https://bibliotekanauki.pl/articles/949817.pdf

Data publikacji:

2019

Wydawca:

Polska Akademia Nauk. Czytelnia Czasopism PAN

Tematy:

discounted LQR control
singular system
disturbance

Opis:

The LQR (linear quadratic regulator) control problem subject to singular system constitutes a optimization problem in which one must be find an optimal control that satisfy the singular system and simultaneously to optimize the quadratic objective functional. In this paper we establish a sufficient condition to obtain the optimal control of discounted LQR optimization problem subject to disturbanced singular system where the disturbance is time varying. The considered problem is solved by transforming the discounted LQR control problem subject to disturbanced singular system into the normal LQR control problem. Some available results in literatures of the normal LQR control problem be used to find the sufficient conditions for the existence of the optimal control for discounted LQR control problem subject to disturbanced singular system. The final result of this paper is in the form a method to find the optimal control of discounted LQR optimization problem subject to disturbanced singular system. The result shows that the disturbance is vanish with the passage of time.

Źródło:

Archives of Control Sciences; 2019, 29, 1; 147-156
1230-2384

Pojawia się w:

Archives of Control Sciences

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 19.

Tytuł:

Uniqueness for a class p-Laplacian problems when a parameter is large

Autorzy:

Alreshidi, B.
Hai, D. D.

Powiązania:

https://bibliotekanauki.pl/articles/29519620.pdf

Data publikacji:

2024

Wydawca:

Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH

Tematy:

singular p-Laplacian
uniqueness
positive solutions

Opis:

We prove uniqueness of positive solutions for the problem $ −Δ_p u = \lambda f(u) $ in $ \Omega, u = 0 $ on $ \delta \Omega $, where $ 1 < p < 2 $ and $ p $ is close to 2, $ \Omega $ is bounded domain in $ \mathbb{R}^n $ with smooth boundary $ ∂Ω, f : [0,∞) → [0,∞) $ with $ f(z) ∼ z \beta $ at $ \infty $ for some $ \beta ∈ (0, 1) $, and $ \lambda $ is a large parameter. The monotonicity assumption on $ f $ is not required even for $ u $ large.

Źródło:

Opuscula Mathematica; 2024, 44, 1; 5-17
1232-9274
2300-6919

Pojawia się w:

Opuscula Mathematica

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 20.

Tytuł:

Singular spectrum analysis as a smoothing method of load variability
Analiza widma szczególnego jako metoda wygładzania zmienności obciążenia

Autorzy:

Cempel, C.
Tabaszewski, M.

Powiązania:

https://bibliotekanauki.pl/articles/327782.pdf

Data publikacji:

2010

Wydawca:

Polska Akademia Nauk. Polskie Towarzystwo Diagnostyki Technicznej PAN

Tematy:

diagnostyka
rozkład na wartości szczególne
analiza widma szczególnego
condition monitoring
singular value decomposition
singular spectrum analysis

Opis:

Application of SVD to fault extraction from the machine symptom observation matrix (SOM) seems to be validated enough, especially by data taken from many real diagnostic cases. However, frequently we have situation of varying machine load during the production process, where by observed primary symptoms are influenced greatly. This concerns generalized symptoms too, so decision making process and forecasting is disturbed. But we can apply some new data smoothing procedure called singular spectrum analysis (SSA), to eliminate load influenced symptom fluctuation, and obtain the machine wear trend only. This seems to be true, as it was shown in the paper, but special care should be taken to choose smoothing approximation order properly.
Zastosowanie rozkładu SVD do wydobycia informacji o uszkodzeniu z symptomowej macierzy obserwacji (ang. SOM) wydaje się być wystarczająco uzasadnione, szczególnie dla danych pochodzących z wielu rzeczywistych przypadków diagnostycznych. Jednakże w wielu przypadkach mamy do czynienia z sytuacją zmiennych obciążeń maszyny podczas procesu produkcji, silnie wpływających na obserwowane symptomy. Dotyczy to także symptomów uogólnionych, co utrudnia proces podejmowania decyzji i prognozowania. Możemy jednak zastosować pewną nową procedurę wygładzania nazywaną analizą widma szczególnego (ang. SSA), aby wyeliminować obciążenia wpływające na fluktuacje symptomu i otrzymać tylko trend zużycia maszyny. Wydaje się to być prawdą, jak zostało pokazane w pracy, jednak z zachowaniem szczególnej uwagi w poprawnym wyborze rzędu przybliżenia w procedurze wygładzania.

Źródło:

Diagnostyka; 2010, 4(56); 3-8
1641-6414
2449-5220

Pojawia się w:

Diagnostyka

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 21.

Tytuł:

The Cayley variational principle for continuous-impact problems: a continuum mechanics based version in the presence of a singular surface
Zasada wariacyjna Cayley’a w zagadnieniu ciągło-uderzeniowym: wersja mechaniki kontinuum z obecnością powierzchni osobliwej

Autorzy:

Irschik, H.

Powiązania:

https://bibliotekanauki.pl/articles/280358.pdf

Data publikacji:

2012

Wydawca:

Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej

Tematy:

variable-mass systems
singular surface
falling chains

Opis:

In 1857, Arthur Cayley presented a variational principle for a class of dynamical problems, which he designated as continuous-impact problems. Cayley exemplified this class by means of a chain hanging over the edge of a table and being set into motion by its own weight. In the following, we present a continuum mechanics based version of the Cayley principle. The moving portion of the chain mentioned by Cayley represents a variable-mass system, and he assumed that the particles of the chain experience a jump in their velocity when being taken into connection with the moving part. We accordingly study a body containing a non-material region of transition, within which certain entities suffer considerable changes of their spatial distribution, and which we replace by equivalent surface growth terms at a singular surface, in order to derive our version of the principle. The falling chain mentioned by Cayley is used as an example problem.
W 1857 roku Arthur Cayley zaprezentował zasadę wariacyjną dla pewnej klasy zagadnień dynamicznych, którą nazwał ciągło-uderzeniową. Cayley zegzemplifikował tę klasę problemem łańcucha zwisającego z krawędzi stołu i wprowadzanego w ruch własnym ciężarem. W niniejszej pracy zasadę Cayley’a przedstawiono w wersji opartej na mechanice kontinuum. Dawny uczony opisał ruchomą część spadającego łańcucha układem o zmiennej masie i założył, że jego fragmenty spoczywające jeszcze na stole doświadczają skokowego przyrostu prędkości w momencie przyłączania się do części wprawionej już w ruch. Nawiązując do podejścia Cayley’a, w obecnym artykule przeprowadzono analizę ruchu ciała zawierającego niematerialny obszar przejściowy, w którym pewne wielkości podlegają znacznym zmianom konfiguracji przestrzennej i które wyrażono zastępczymi przyrostami na powierzchni osobliwej. Takie sformułowanie pozwoliło wyprowadzić własną wersję zasady Cayley’a, a spadający łańcuch posłużył jako przykład przedstawionej analizy.

Źródło:

Journal of Theoretical and Applied Mechanics; 2012, 50, 3; 717-727
1429-2955

Pojawia się w:

Journal of Theoretical and Applied Mechanics

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 22.

Tytuł:

Using Singular Value Decomposition (SVD) as a solution for search result clustering

Autorzy:

Abdulla, H. D.
Abdelrahman, A. S.
Snasel, V.

Powiązania:

https://bibliotekanauki.pl/articles/377259.pdf

Data publikacji:

2014

Wydawca:

Politechnika Poznańska. Wydawnictwo Politechniki Poznańskiej

Tematy:

singular value decomposition
clustering
self-organizing map

Opis:

There are many search engines in the web, but they return a long list of search results, ranked by their relevancies to the given query. Web users have to go through the list and examine the titles and (short) snippets sequentially to identify their required results. In this paper we present how usage of Singular Value Decomposition (SVD) as a very good solution for search results clustering. Results are presented by visualizing neural network. Neural network is responsive for reducing result dimension to two dimensional space and we are able to present result as a picture that we are able to analyze.

Źródło:

Poznan University of Technology Academic Journals. Electrical Engineering; 2014, 80; 71-78
1897-0737

Pojawia się w:

Poznan University of Technology Academic Journals. Electrical Engineering

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 23.

Tytuł:

Parametric Borel summability for some semilinear system of partial differential equations

Autorzy:

Yamazawa, H.
Yoshino, M.

Powiązania:

https://bibliotekanauki.pl/articles/254935.pdf

Data publikacji:

2015

Wydawca:

Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH

Tematy:

Borel summability
singular perturbation
Euler type operator

Opis:

In this paper we study the Borel summability of formal solutions with a parameter of first order semilinear system of partial differential equations with n independent variables. In [Singular perturbation of linear systems with a regular singularity, J. Dynam. Control. Syst. 8 (2002), 313-322], Balser and Kostov proved the Borel summability of formal solutions with respect to a singular perturbation parameter for a linear equation with one independent variable. We shall extend their results to a semilinear system of equations with general independent variables.

Źródło:

Opuscula Mathematica; 2015, 35, 5; 825-845
1232-9274
2300-6919

Pojawia się w:

Opuscula Mathematica

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 24.

Tytuł:

Investigating the numerical range and q-numerical range of non square matrices

Autorzy:

Aretaki, A
Maroulas, J.

Powiązania:

https://bibliotekanauki.pl/articles/255736.pdf

Data publikacji:

2011

Wydawca:

Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH

Tematy:

numerical range
projectors
matrix norms
singular values

Opis:

A presentation of numerical ranges for rectangular matrices is undertaken in this paper, introducing two different definitions and elaborating basic properties. Further, we extend to the q-numerical range.

Źródło:

Opuscula Mathematica; 2011, 31, 3; 303-315
1232-9274
2300-6919

Pojawia się w:

Opuscula Mathematica

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 25.

Tytuł:

Positive solutions of a singular fractional boundary value problem with a fractional boundary condition

Autorzy:

Lyons, J. W.
Neugebauer, J. T.

Powiązania:

https://bibliotekanauki.pl/articles/255965.pdf

Data publikacji:

2017

Wydawca:

Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH

Tematy:

fractional differential equation
singular problem
fixed point

Opis:

For α ∈ (1,2] the singular fractional boundary value problem [formula] satisfying the boundary conditions [formula] where β ∈ (0,α - 1], μ ∈ (0,α - 1], and [formula] are Riemann-Liouville derivatives of order α, β, and μ respectively, is considered. Here ƒ satisfies a local Carathéodory condition, and ƒ (t, x, y) may be singular at the value 0 in its space variable x. Using regularization and sequential techniques and Krasnosel’skii’s fixed point theorem, it is shown this boundary value problem has a positive solution. An example is given.

Źródło:

Opuscula Mathematica; 2017, 37, 3; 421-434
1232-9274
2300-6919

Pojawia się w:

Opuscula Mathematica

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

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Skocz do pozycji: 26.

Tytuł:

Checking of the positivity of descriptor linear systems with singular pencils

Autorzy:

Kaczorek, T.

Powiązania:

https://bibliotekanauki.pl/articles/229759.pdf

Data publikacji:

2012

Wydawca:

Polska Akademia Nauk. Czytelnia Czasopism PAN

Tematy:

checking
positivity
descriptor
linear systems
singular pencil

Opis:

A method for checking of the positivity of descriptor continuous-time and discrete-time linear systems with singular pencil is proposed. The method is based on elementary row and column operations on the matrices of descriptor systems. Necessary and sufficient conditions for the positivity of the descriptor systems are established.

Źródło:

Archives of Control Sciences; 2012, 22, 1; 77-86
1230-2384

Pojawia się w:

Archives of Control Sciences

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 27.

Tytuł:

A study of parallel techniques for dimensionality reduction and its impact on the quality of text processing algorithms

Autorzy:

Pietroń, M.
Wielgosz, M.
Karwatowski, M.
Wiatr, K.

Powiązania:

https://bibliotekanauki.pl/articles/114190.pdf

Data publikacji:

2015

Wydawca:

Stowarzyszenie Inżynierów i Techników Mechaników Polskich

Tematy:

singular value decomposition
vector space model
TFIDF

Opis:

The presented algorithms employ the Vector Space Model (VSM) and its enhancements such as TFIDF (Term Frequency Inverse Document Frequency) with Singular Value Decomposition (SVD). TFIDF were applied to emphasize the important features of documents and SVD was used to reduce the analysis space. Consequently, a series of experiments were conducted. They revealed important properties of the algorithms and their accuracy. The accuracy of the algorithms was estimated in terms of their ability to match the human classification of the subject. For unsupervised algorithms the entropy was used as a quality evaluation measure. The combination of VSM, TFIDF, and SVD came out to be the best performing unsupervised algorithm with entropy of 0.16.

Źródło:

Measurement Automation Monitoring; 2015, 61, 7; 352-353
2450-2855

Pojawia się w:

Measurement Automation Monitoring

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

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Skocz do pozycji: 28.

Tytuł:

Externally and internally positive singular discrete-time linear systems

Autorzy:

Kaczorek, T.

Powiązania:

https://bibliotekanauki.pl/articles/907996.pdf

Data publikacji:

2002

Wydawca:

Uniwersytet Zielonogórski. Oficyna Wydawnicza

Tematy:

elektrotechnika
externally
internally
positive
singular
linear
system

Opis:

Notions of externally and internally positive singular discrete-time linear systems are introduced. It is shown that a singular discrete-time linear system is externally positive if and only if its impulse response matrix is non-negative. Sufficient conditions are established under which a single-output singular discrete-time system with matrices in canonical forms is internally positive. It is shown that if a singular system is weakly positive (all matrices E, A, B, C are non-negative), then it is not internally positive.

Źródło:

International Journal of Applied Mathematics and Computer Science; 2002, 12, 2; 197-202
1641-876X
2083-8492

Pojawia się w:

International Journal of Applied Mathematics and Computer Science

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 29.

Tytuł:

Oscillatory singular integrals on weighted Hardy spaces

Autorzy:

Hu, Yue

Powiązania:

https://bibliotekanauki.pl/articles/1293188.pdf

Data publikacji:

1992

Wydawca:

Polska Akademia Nauk. Instytut Matematyczny PAN

Tematy:

oscillatory singular integrals
H¹ space
A₁ condition

Opis:

Let $Tf(x) = p.v. ʃ_{ℝ¹} e^{iP(x-y)} f(y)/(x-y) dy$, where P is a real polynomial on ℝ. It is proved that T is bounded on the weighted H¹(wdx) space with w ∈ A₁.

Źródło:

Studia Mathematica; 1992, 102, 2; 145-156
0039-3223

Pojawia się w:

Studia Mathematica

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 30.

Tytuł:

On 1-regular ordinary differential operators

Autorzy:

Łysik, Grzegorz

Powiązania:

https://bibliotekanauki.pl/articles/1207973.pdf

Data publikacji:

2000

Wydawca:

Polska Akademia Nauk. Instytut Matematyczny PAN

Tematy:

singular differential equations
Mellin transformation
Laplace integrals

Opis:

Solutions to singular linear ordinary differential equations with analytic coefficients are found in the form of Laplace type integrals.

Źródło:

Annales Polonici Mathematici; 2000, 74, 1; 201-214
0066-2216

Pojawia się w:

Annales Polonici Mathematici

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

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Skocz do pozycji: 31.

Tytuł:

Design of regular positive and stable descriptor systems via state-feedbacks for descriptor continuous-time linear systems with singular pencils

Autorzy:

Kaczorek, T.

Powiązania:

https://bibliotekanauki.pl/articles/229306.pdf

Data publikacji:

2014

Wydawca:

Polska Akademia Nauk. Czytelnia Czasopism PAN

Tematy:

design
positivity
descriptor
linear
system
singular pencil

Opis:

A new method is proposed of design of regular positive and asymptotically stable descriptor systems by the use of state-feedbacks for descriptor continuous-time linear systems with singular pencils. The method is based on the reduction of the descriptor system by elementary row and column operations to special form. A procedure for the design of the state-feedbacks gain matrix is presented and illustrated by a numerical example.

Źródło:

Archives of Control Sciences; 2014, 24, 3; 289-297
1230-2384

Pojawia się w:

Archives of Control Sciences

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 32.

Tytuł:

Singular Turán Numbers and Worm-Colorings

Autorzy:

Gerbner, Dániel
Patkós, Balázs
Vizer, Máté
Tuza, Zsolt

Powiązania:

https://bibliotekanauki.pl/articles/32222590.pdf

Data publikacji:

2022-11-01

Wydawca:

Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii

Tematy:

Turán number
WORM-coloring
singular Turán numbers

Opis:

A subgraph G of H is singular if the vertices of G either have the same degree in H or have pairwise distinct degrees in H. The largest number of edges of a graph on n vertices that does not contain a singular copy of G is denoted by T_S(n, G). Caro and Tuza in [Singular Ramsey and Turán numbers, Theory Appl. Graphs 6 (2019) 1–32] obtained the asymptotics of T_S(n, G) for every graph G, but determined the exact value of this function only in the case G = K₃ and n ≡ 2 (mod 4). We determine T_S(n, K3) for all n ≡ 0 (mod 4) and n ≡ 1 (mod 4), and also T_S(n, K_r+1) for large enough n that is divisible by r. We also explore the connection to the so-called G-WORM colorings (vertex colorings without rainbow or monochromatic copies of G) and obtain new results regarding the largest number of edges that a graph with a G-WORM coloring can have.

Źródło:

Discussiones Mathematicae Graph Theory; 2022, 42, 4; 1061-1074
2083-5892

Pojawia się w:

Discussiones Mathematicae Graph Theory

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 33.

Tytuł:

Forma dekretu poszczególnego w kanonicznym porządku prawnym (kan. 51 KPK)
The form of a singular decree in the canonical legal order (Can. 51 CIC)

Autorzy:

DZIERŻON, GINTER

Powiązania:

https://bibliotekanauki.pl/articles/661423.pdf

Data publikacji:

2015

Wydawca:

Uniwersytet Kardynała Stefana Wyszyńskiego w Warszawie

Tematy:

poszczególny dekret
forma poszczególnego dekretu
kanoniczny porządek prawny
singular decree
the form of a singular decree
canonical legal order

Opis:

The author of the presented article carried out a thorough interpretation of can. 51 CIC. e focus of his attention were 2 issues: the question of a writ- ten form of a decree and the problem of motivation behind it. According to his analysis, the obligation to issue a decree in writing is not obvious. The disposition included in can. 51 CICI does not accord with the criteria determined in can. 10 CIC which concerns invalidating and disqualifying laws. e author proved that the canonical legal order includes regulations concerning the written form of decrees which meet the conditions dened in can. 10 CIC. Such a legislative mechanism was used in can. 474 CIC according to which acts of the curia in order to have juridic eect must be signed by the ordinary. e author believes that the written form guaran- tees the validity and security of administrative acts and is necessary for evidential purposes. Another focus of the author’s attention was the question of motivation of a decree. As he believes, from the perspective of administrative practice, the most appropriate solution would be for every issued act to include its motivation. In consequence, the addressee of an act would learn about both legal and actual reasons behind a particular decision. The author proved that not meeting the requirement concerning the motivation of a decree does not result in its invalidity but makes it illegal since the norm included in can. 51 CIC does not meet the conditions codi- ed in can. 10 CIC. 
  W zaprezentowanym opracowaniu autor dokonał szczegółowej interpretacji kan. 51 KPK. Przedmiotem jego zainteresowania stały się dwa wątki: kwestia pisemności dekretu oraz problem motywacji tego aktu. Z przeprowadzonych analiz wynika, iż konieczność wydania dekretu w formie pisemnej nie jest oczywistością. Dyspozycja bowiem kan. 51 KPK nie spełnia kryterium określonego w kan. 10 KPK dotyczącego ustaw unieważniających i uniezdalniających. Autor wykazał, iż w kanonicznym porządku prawnym występują regulacje dotyczące pisemności aktów, które spełniają warunki określone w kan. 10 KPK. Taka technika legislacyjna została zastosowana w kan.  474 KPK, zgodnie z którym akta kurii diecezjalnej, aby uzyskać skuteczność prawną do ważności powinny być podpisane przez ordynariusza. W opinii Autora, forma pisemna aktu jest gwarantem pewności i bezpieczeństwa aktów administracyjnych, a także jest konieczna dla celów dowodowych. Obiektem uwagi Autora stał się również problem motywacji dekretu. Stoi on na stanowisku, iż punktu widzenia praktyki administracyjnej najbardziej stosowne byłoby przyjęcie rozwiązania, aby każdy wydawany dekret zawierałby motywację. Tym sposobem bowiem adresat aktu poznałby zarówno racje prawne, jak i faktyczne podjętej decyzji. Wykazał on, iż niewypełnienie wymogu co do motywacji nie skutkuje nieważnością dekretu, ale wiąże się z jego nielegalnością, ponieważ zapis kan. 51 KPK nie spełnia warunków, o których mowa w kan. 10 KPK.

Źródło:

Prawo Kanoniczne; 2015, 58, 2; 3-14
2353-8104

Pojawia się w:

Prawo Kanoniczne

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 34.

Tytuł:

Pseudo-phase mapping of speckle fields using 2D Hilbert transformation

Autorzy:

Zenkova, C. Y.
Gorsky, M. P.
Ryabiy, P. A.

Powiązania:

https://bibliotekanauki.pl/articles/174971.pdf

Data publikacji:

2016

Wydawca:

Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej

Tematy:

speckle field
singular points
saddle points
phase problem

Opis:

The use of a "window" 2D Hilbert transform for the reconstruction of the phase distribution of the intensity of a speckle field is proposed. It is shown that the advantage of this approach consists in the invariance of a phase map to a change of the position of the kernel of transformation and in the possibility to reconstruct the structure-forming elements of the skeleton of an optical field, including singular points and saddle points. We demonstrate the possibility to reconstruct the equi-phase lines within a narrow confidence interval, and introduce an additional algorithm for solving the phase problem for random 2D intensity distributions.

Źródło:

Optica Applicata; 2016, 46, 1; 153-162
0078-5466
1899-7015

Pojawia się w:

Optica Applicata

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 35.

Tytuł:

Noether and matrix methods to construct local symmetries of Lagrangians

Autorzy:

Lam-Estrada, P.
Ovando, G.
López-Bonilla, J.
López-Vázquez, R.
Vidal-Beltrán, S.

Powiązania:

https://bibliotekanauki.pl/articles/1177899.pdf

Data publikacji:

2018

Wydawca:

Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN

Tematy:

Gauge identities
Local symmetries
Noether theorem
Singular Lagrangians

Opis:

We exhibit an elementary presentation of matrix and Noether techniques to construct infinitesimal point symmetries of Lagrangians. Besides, we employ the Lanczos approach to Noether’s theorem to obtain the first integral associated with each symmetry. We show applications to several singular Lagrangians of interest in classical mechanics.

Źródło:

World Scientific News; 2018, 97; 51-68
2392-2192

Pojawia się w:

World Scientific News

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 36.

Tytuł:

Realization problem for singular positive continuous-time systems with delays

Autorzy:

Kaczorek, T.

Powiązania:

https://bibliotekanauki.pl/articles/969739.pdf

Data publikacji:

2007

Wydawca:

Polska Akademia Nauk. Instytut Badań Systemowych PAN

Tematy:

realization
positive
singular
continuous-time
system
existence
procedure

Opis:

The positive realization problem for a class of singular continuous-time linear SISO systems with delays in state and in output is addressed. The notions of canonical forms of matrices and of dual systems are extended for singular linear systems with delays. Necessary and sufficient conditions for positivity of SISO singular continuous-time systems with delays and sufficient conditions for the existence of a positive singular realization are established. A procedure for computation of a positive singular realization of a given transfer function is proposed and illustrated by a numerical example.

Źródło:

Control and Cybernetics; 2007, 36, 1; 47-57
0324-8569

Pojawia się w:

Control and Cybernetics

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 37.

Tytuł:

Singular controls and chattering arcs in optimal control problems arising in biomedicine

Autorzy:

Ledzewicz, U.
Schattler, H.

Powiązania:

https://bibliotekanauki.pl/articles/970774.pdf

Data publikacji:

2009

Wydawca:

Polska Akademia Nauk. Instytut Badań Systemowych PAN

Tematy:

optimal control
singular controls
biomedical models
anti-angiogenesis

Opis:

We consider an optimal control problem of the Mayer-type for a single-input, control affine, nonlinear system in small dimension. In this paper, we analyze effects that a modeling extension has on the optimality of singular controls when the control is replaced with the output of a first-order, time-invariant linear system driven by a new control. This analysis is motivated by an optimal control problem for a novel cancer treatment method, tumor anti-angiogenesis, when such a linear differential equation, which represents the pharmacokinetics of the therapeutic agent, is added to the model. We show that formulas that define a singular control of order 1 and its associated singular arc carry over verbatim under this model extension, albeit with a different interpretation. But the intrinsic order of the singular control increases to 2. As a, consequence, optimal concatenation sequences with the singular control change and the possibility of optimal chattering arcs arises.

Źródło:

Control and Cybernetics; 2009, 38, 4B; 1501-1523
0324-8569

Pojawia się w:

Control and Cybernetics

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 38.

Tytuł:

Symulacja singularnych liniowych układów ciągłych
Simulation of singular continous-time linear systems

Autorzy:

Rogowski, K.
Kaczorek, T.

Powiązania:

https://bibliotekanauki.pl/articles/151620.pdf

Data publikacji:

2008

Wydawca:

Stowarzyszenie Inżynierów i Techników Mechaników Polskich

Tematy:

symulacja
singularny
układ liniowy
simulation
singular
linear system

Opis:

Podano nową metodę symulacji singularnych liniowych układów ciągłych opartą na dekompozycji Weierstrassa-Kroneckera na trzy podukłady: standardowy, ściśle singularny i statyczny. Metoda została zilustrowana przykładem numerycznym i przebiegami czasowymi.
A new metod of singular continous-time linear systems simulation based on Weierstrass-Kronecker decomposition for three: standard, strictly singular and static subsystems is presented. Illustrating numerical example with simulations results are given.

Źródło:

Pomiary Automatyka Kontrola; 2008, R. 54, nr 9, 9; 620-622
0032-4140

Pojawia się w:

Pomiary Automatyka Kontrola

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 39.

Tytuł:

Eigenvalue asymptotics for the Sturm-Liouville operator with potential having a strong local negative singularity

Autorzy:

Nursultanov, M.
Rozenblum, G.

Powiązania:

https://bibliotekanauki.pl/articles/255426.pdf

Data publikacji:

2017

Wydawca:

Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH

Tematy:

Sturm-Liouville operator
singular potential
asymptotics of eigenvalues

Opis:

We find asymptotic formulas for the eigenvalues of the Sturm-Liouville operator on the finite interval, with potential having a strong negative singularity at one endpoint. This is the case of limit circle in H. Weyl sense. We establish that, unlike the case of an infinite interval, the asymptotics for positive eigenvalues does not depend on the potential and it is the same as in the regular case. The asymptotics of the negative eigenvalues may depend on the potential quite strongly, however there are always asymptotically fewer negative eigenvalues than positive ones. By unknown reasons this type of problems had not been studied previously.

Źródło:

Opuscula Mathematica; 2017, 37, 1; 109-139
1232-9274
2300-6919

Pojawia się w:

Opuscula Mathematica

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 40.

Tytuł:

Mellin analysis of partial differential equations in papers of B. Ziemian

Autorzy:

Kołakowski, Henryk

Powiązania:

https://bibliotekanauki.pl/articles/1207930.pdf

Data publikacji:

2000

Wydawca:

Polska Akademia Nauk. Instytut Matematyczny PAN

Tematy:

Mellin transformation
propagation of singularities
singular elliptic operators

Opis:

Existence and regularity theorems for Fuchsian type differential operators and the theory of second microlocalization are presented.

Źródło:

Annales Polonici Mathematici; 2000, 74, 1; 27-33
0066-2216

Pojawia się w:

Annales Polonici Mathematici

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 41.

Tytuł:

Distributional fractional powers of the Laplacean. Riesz potentials

Autorzy:

Martínez, Celso
Sanzi, Miguel
Periago, Francisco

Powiązania:

https://bibliotekanauki.pl/articles/1216946.pdf

Data publikacji:

1999

Wydawca:

Polska Akademia Nauk. Instytut Matematyczny PAN

Tematy:

fractional powers
Laplacean operator
Riesz potentials
singular integrals

Opis:

For different reasons it is very useful to have at one's disposal a duality formula for the fractional powers of the Laplacean, namely, $((-Δ)^α u,ϕ ) = (u,(-Δ)^α ϕ)$, α ∈ ℂ, for ϕ belonging to a suitable function space and u to its topological dual. Unfortunately, this formula makes no sense in the classical spaces of distributions. For this reason we introduce a new space of distributions where the above formula can be established. Finally, we apply this distributional point of view on the fractional powers of the Laplacean to obtain some properties of the Riesz potentials in a wide class of spaces which contains the $L^p$-spaces.

Źródło:

Studia Mathematica; 1999, 135, 3; 253-271
0039-3223

Pojawia się w:

Studia Mathematica

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 42.

Tytuł:

Singular extremals in multi-input time-optimal problems: a sufficient condition

Autorzy:

Chittaro, F. C.
Stefani, G.

Powiązania:

https://bibliotekanauki.pl/articles/970214.pdf

Data publikacji:

2010

Wydawca:

Polska Akademia Nauk. Instytut Badań Systemowych PAN

Tematy:

second variation
singular extremal
sufficient condition
Hamiltonian methods

Opis:

In this paper we study second order sufficient conditions for the strong-local optimality of singular Pontryagin extremals. In particular, we focus on the minimum-time problem for a control-affine system with vector inputs. We use Hamiltonian methods to prove that the coercivity of a suitably-defined second variation - plus an involutivity assumption on the distribution of the controlled fields - is a sufficient condition for the strong optimality of a candidate extremal.

Źródło:

Control and Cybernetics; 2010, 39, 4; 1029-1068
0324-8569

Pojawia się w:

Control and Cybernetics

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 43.

Tytuł:

Singular elliptic problems with Dirichlet or mixed Dirichlet-Neumann non-homogeneous boundary conditions

Autorzy:

Godoy, Tomas

Powiązania:

https://bibliotekanauki.pl/articles/29519241.pdf

Data publikacji:

2023

Wydawca:

Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH

Tematy:

singular elliptic problems
mixed boundary conditions
weak solutions

Opis:

Let Ω be a $ C^2 $ bounded domain in $ R^n $ such that $ ∂Ω = Γ_1 ∪ Γ_2 $, where $ Γ_1 $ and $ Γ_2 $ are disjoint closed subsets of ∂Ω, and consider the problem −Δu = g(·, u) in Ω, u = τ on $ Γ_1 $, $ \frac{∂u}{ ∂ν} = η $ on $ Γ_2 $, where $ 0 ≤ τ ∈ W^{\frac{1}{2} ,2 } (Γ_1),$ $ η ∈ (H_{0, Γ_1}^1 (Ω))^′ $, and $ g : Ω×(0,∞) → \mathbb{R} $ is a nonnegative Carathéodory function. Under suitable assumptions on g and η we prove the existence and uniqueness of a positive weak solution of this problem. Our assumptions allow g to be singular at s = 0 and also at $ x ∈ S $ for some suitable subsets S ⊂ Ω. The Dirichlet problem −Δu = g(·, u) in Ω, u = σ on ∂Ω is also studied in the case when $ 0 ≤ σ ∈ W^{\frac{1}{2} ,2} (Ω) $.

Źródło:

Opuscula Mathematica; 2023, 43, 1; 19-46
1232-9274
2300-6919

Pojawia się w:

Opuscula Mathematica

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 44.

Tytuł:

The first eigencurve for a Neumann boundary problem involving p-Laplacian with essentially bounded weights

Autorzy:

Sanhaji, Ahmed
Dakkak, Ahmed
Moussaoui, Mimoun

Powiązania:

https://bibliotekanauki.pl/articles/29519370.pdf

Data publikacji:

2023

Wydawca:

Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH

Tematy:

p-Laplacian
first eigencurve
singular weights
Neumann boundary conditions

Opis:

This article is intended to prove the existence and uniqueness of the first eigencurve, for a homogeneous Neumann problem with singular weights associated with the equation $ −\Delta_p u = \alpha m_1 |u|^{p−2} u + \beta m_2 |u|^{p−2} u $ in a bounded domain $ \Omega \subset \mathbb{R}^N $. We then establish many properties of this eigencurve, particularly the continuity, variational characterization, asymptotic behavior, concavity and the differentiability.

Źródło:

Opuscula Mathematica; 2023, 43, 4; 559-574
1232-9274
2300-6919

Pojawia się w:

Opuscula Mathematica

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

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Skocz do pozycji: 45.

Tytuł:

Generalized analytic functions of Bogdan Ziemian

Autorzy:

Łysik, Grzegorz

Powiązania:

https://bibliotekanauki.pl/articles/1207960.pdf

Data publikacji:

2000

Wydawca:

Polska Akademia Nauk. Instytut Matematyczny PAN

Tematy:

Mellin transformation
Laplace distributions
special functions
singular differential operators

Opis:

Definitions, properties, examples and applications of generalized analytic functions introduced by B. Ziemian are presented.

Źródło:

Annales Polonici Mathematici; 2000, 74, 1; 35-41
0066-2216

Pojawia się w:

Annales Polonici Mathematici

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 46.

Tytuł:

Robust soft variable structure control of perturbed singular systems with constrained input

Autorzy:

Asadinia, M. S.
Binazadeh, T.

Powiązania:

https://bibliotekanauki.pl/articles/205506.pdf

Data publikacji:

2017

Wydawca:

Polska Akademia Nauk. Instytut Badań Systemowych PAN

Tematy:

singular systems
robust stabilization
vanishing perturbation
non-vanishing perturbation

Opis:

This paper investigates the robust soft variable structure (RSVS) control technique for perturbed singular systems with constrained input control. The aim of the RSVS control law, in addition to achieving desirable control performance for the constrained input, is the robust stability of the closed-loop system in the presence of perturbation. In this paper, the RSVS control for perturbed singular systems is designed for two cases. First, it is assumed that the perturbation term vanishes at the origin. In this case, the proposed RSVS controller leads to asymptotic stabilization of the perturbed singular system. In the second case, the perturbed singular systems with non-vanishing perturbation are considered and the robustness of RSVS is also investigated. In this situation, the proposed controller guarantees practical stability of the perturbed singular system. Finally, computer simulations are provided for two examples to verify the theoretical results.

Źródło:

Control and Cybernetics; 2017, 46, 4; 345-360
0324-8569

Pojawia się w:

Control and Cybernetics

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 47.

Tytuł:

Asymptotic study of elastic half-plane with embedded punch
Analiza asymtotyczna zagadnienia kontaktowego stempla i półprzestrzeni sprężystej

Autorzy:

Andrianov, I. V.
Awrejcewicz, J.
Kirichek, Yu. A.
Koblik, S. G.

Powiązania:

https://bibliotekanauki.pl/articles/280842.pdf

Data publikacji:

2007

Wydawca:

Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej

Tematy:

mixed boundary value problem
singular asymptotics
complex variable theory

Opis:

A contact problem for an elastic half-plane and an embedded rigid punch is studied. The employed mathematical model describes the behavior of a soil with embedded foundation. The analytical solution geverning the stress field behaviour is derived. Singular perturbation and complex analysis techniques are used.
W pracy rozważono zagadnienie kontaktowe związane z oddziaływaniem sztywnego stempla i półprzestrzeni sprężystej. Analizowany problem może np. modelować fundamenty budowli usytuowane w podatnym gruncie. Sformułowano w postaci analitycznej pole naprężeń przy użyciu metody perturbacji osobliwych i techniki zmiennych zespolonych.

Źródło:

Journal of Theoretical and Applied Mechanics; 2007, 45, 1; 5-14
1429-2955

Pojawia się w:

Journal of Theoretical and Applied Mechanics

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

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Skocz do pozycji: 48.

Tytuł:

Approximate solutions of a singular integral equation with Cauchy kernels in the quarter plane

Autorzy:

Pylak, D.

Powiązania:

https://bibliotekanauki.pl/articles/255775.pdf

Data publikacji:

2008

Wydawca:

Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH

Tematy:

singular integral equation
Cauchy kernel
Chebyshev and Jacobi polynomials

Opis:

In the paper, we present explicit formulae for the solution of the singular integral equation with Cauchy kernels in the quarter plane. Next, Jacobi and Chebyshev polynomials are used to derive approximate solutions of this equation.

Źródło:

Opuscula Mathematica; 2008, 28, 2; 179-194
1232-9274
2300-6919

Pojawia się w:

Opuscula Mathematica

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

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Skocz do pozycji: 49.

Tytuł:

Weighted estimates for commutators of linear operators

Autorzy:

Alvarez, Josefina
Bagby, Richard
Kurtz, Douglas
Pérez, Carlos

Powiązania:

https://bibliotekanauki.pl/articles/1292924.pdf

Data publikacji:

1993

Wydawca:

Polska Akademia Nauk. Instytut Matematyczny PAN

Tematy:

bounded mean oscillation
singular integrals
maximal functions
weighted inequalities

Opis:

We study boundedness properties of commutators of general linear operators with real-valued BMO functions on weighted $L^p$ spaces. We then derive applications to particular important operators, such as Calderón-Zygmund type operators, pseudo-differential operators, multipliers, rough singular integrals and maximal type operators.

Źródło:

Studia Mathematica; 1993, 104, 2; 195-209
0039-3223

Pojawia się w:

Studia Mathematica

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 50.

Tytuł:

A multidimensional singular stochastic control problem on a finite time horizon

Autorzy:

Boryc, Marcin
Kruk, Łukasz

Powiązania:

https://bibliotekanauki.pl/articles/747102.pdf

Data publikacji:

2015

Wydawca:

Uniwersytet Marii Curie-Skłodowskiej. Wydawnictwo Uniwersytetu Marii Curie-Skłodowskiej

Tematy:

Singular stochastic control
generalized derivative
HJB equation
optimal control

Opis:

A singular stochastic control problem in n dimensions with timedependent coefficients on a finite time horizon is considered. We show that the value function for this problem is a generalized solution of the corresponding HJB equation with locally bounded second derivatives with respect to the space variables and the first derivative with respect to time. Moreover, we prove that an optimal control exists and is unique.

Źródło:

Annales Universitatis Mariae Curie-Skłodowska, sectio A – Mathematica; 2015, 69, 1
0365-1029
2083-7402

Pojawia się w:

Annales Universitatis Mariae Curie-Skłodowska, sectio A – Mathematica

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 51.

Tytuł:

Ochrona własności rolniczej w nawiązaniu do koncepcji własności rolniczej Profesora Andrzeja Stelmachowskiego
Protection of agricultural property in reference to the concept of agricultural property by professor Andrzej Stelmachowski

Autorzy:

Korzycka-Iwanow, Małgorzata

Powiązania:

https://bibliotekanauki.pl/articles/531116.pdf

Data publikacji:

2011

Wydawca:

Uniwersytet w Białymstoku. Wydawnictwo Temida 2

Tematy:

agricultural property
singular flexibility
function of property
agricultural holding

Opis:

The concept of agricultural property as proposed by A.Stelmachowski relies on the association of the original construction of property law with its specific object, i.e. the farmstead. According to this concept, agricultural property (specified in respect of the matter of ownership) is a complex of laws and obligations describing the legal standing of the subject – farm owner. The concept of agricultural property is an important element of the doctrinal accomplishment underlying the distinguishing of agricultural law as a new branch of legislation; it may also form – on the didactic level – an axis to organise the presentation of agricultural law institutions. Core ownership issues are obviously regulated by civil law. To describe the general features of property law, as a particular legal category, A.Stelmachowski indicates that property law 1) possesses the most comprehensive content as regards the relationship of the subject to the property attributed to him; 2) awards the owner exclusive right (a certain monopoly) as regards a specified object; 3) is characterized by a singular flexibility. All of these features can be referred to various kinds of ownership, regardless of its subject, including agricultural property. The originality of A. Stelmachowski’s approach to ownership arises from a proposed construction which is different to the classic, civil law model of ownership. This model has been inherited from Roman law (triad of ownership), which stressed the absolute rights of the owner. The owner had rights but no obligations towards the others, on the contrary, they are obligated to respect the rights of the owner. The protection of agricultural property is a continuation of the essential idea of the concept Author, and thus encompasses not only the substantive nature of agricultural law but property, that is a farmstead, itself. Important are both the subject and the scope (intensity) of protection. To protect the individual components civil regulations on property are applied, and to protect the farm, it is necessary to restrict the right to dispose of its components at will. When considering the subject of protection, one should take note of two elements: 1) what goods in various historical periods effected protection of the property law, and equally 2) whose interests were taken into account when awarding the protection, in other words, this will be a query regarding the function of property law. The interest (function) which brought about protection of agricultural property in the legal order currently in place in Poland could be described as execution by farmstead proprietors of European Union legislation on the use of agricultural holdings. Similarly as in the period of socialist economy in agriculture, the legal measures are rooted in a model of farming administration developed outside Poland, and introduced here.

Źródło:

Studia Iuridica Agraria; 2011, 9; 115-129
1642-0438

Pojawia się w:

Studia Iuridica Agraria

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 52.

Tytuł:

Positive fractional continuous-time linear systems with singular pencils

Autorzy:

Kaczorek, T.

Powiązania:

https://bibliotekanauki.pl/articles/201013.pdf

Data publikacji:

2012

Wydawca:

Polska Akademia Nauk. Czytelnia Czasopism PAN

Tematy:

positive
fractional
descriptor
continuous-time
linear
system
singular pencil

Opis:

A method for checking the positivity and finding the solution to the positive fractional descriptor continuous-time linear systems with singular pencils is proposed. The method is based on elementary row and column operations of the fractional descriptor systems to equivalent standard systems with some algebraic constraints on state variables and inputs. Necessary and sufficient conditions for the positivity of the fractional descriptor systems are established.

Źródło:

Bulletin of the Polish Academy of Sciences. Technical Sciences; 2012, 60, 1; 9-12
0239-7528

Pojawia się w:

Bulletin of the Polish Academy of Sciences. Technical Sciences

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 53.

Tytuł:

Statistical modelling and forecasting of wheat and meslin export from Ukraine using the singular spectral analysis

Autorzy:

Chala, Tetyana
Korepanov, Oleksiy
Lazebnyk, Iuliia
Chernenko, Daryna
Korepanov, Georgii

Powiązania:

https://bibliotekanauki.pl/articles/10184472.pdf

Data publikacji:

2023-02-24

Wydawca:

Główny Urząd Statystyczny

Tematy:

export
forecasting
singular spectrum analysis
Ukraine
wheat and meslin

Opis:

The article addresses the problems related to the functioning of the worldwide market of wheat and meslin. The authors identify the countries that over the past 17 years have been among the top 10 world leaders in terms of the value of export and import of wheat and meslin. The structure of wheat export by Ukrainian regions is analysed in comparison with the total export. The localisation coefficient is applied to measure the regional unevenness of the distribution of wheat export volumes and the total export by regions of the country. The modelling and forecasting of the volumes and prices of export of wheat and meslin from Ukraine are based on Singular Spectrum Analysis. The study particularly focuses on the individual components of time series, such as trend, annual, semi-annual, four-month, three-month seasonal components. The reliability of the forecast is confirmed by the calculation of the MAPE forecast error and Henry Theil’s inequality coefficient. The article proposes an algorithm for calculating the relative indicators of the structure for the individual components of the reconstructed time series, identified through the singular spectral analysis.

Źródło:

Statistics in Transition new series; 2023, 24, 1; 169-197
1234-7655

Pojawia się w:

Statistics in Transition new series

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

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Skocz do pozycji: 54.

Tytuł:

A simple trolley-like model in the presence of a nonlinear friction and a bounded fuel expenditure

Autorzy:

Dmitruk, Andrei
Samylovskiy, Ivan

Powiązania:

https://bibliotekanauki.pl/articles/729308.pdf

Data publikacji:

2013

Wydawca:

Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii

Tematy:

optimal control problem
Pontryagin Maximum Principle
extremals
singular arcs

Opis:

We consider a problem of maximization of the distance traveled by a material point in the presence of a nonlinear friction under a bounded thrust and fuel expenditure. Using the maximum principle we obtain the form of optimal control and establish conditions under which it contains a singular subarc. This problem seems to be the simplest one having a mechanical sense in which singular subarcs appear in a nontrivial way.

Źródło:

Discussiones Mathematicae, Differential Inclusions, Control and Optimization; 2013, 33, 2; 135-147
1509-9407

Pojawia się w:

Discussiones Mathematicae, Differential Inclusions, Control and Optimization

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

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Skocz do pozycji: 55.

Tytuł:

Controllability of degenerate and singular parabolic problems: the double strong case with Neumann boundary conditionsControllability of degenerate and singular parabolic problems: the double strong case with Neumann boundary conditions

Autorzy:

Fragnelli, Genni
Mugnai, Dimitri

Powiązania:

https://bibliotekanauki.pl/articles/952835.pdf

Data publikacji:

2019

Wydawca:

Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH

Tematy:

strongly singular/degenerate equations
non smooth coefficients
null controllability

Opis:

We prove a null controllability result for a parabolic problem with Neumann boundary conditions. We consider non smooth coefficients in presence of a strongly singular potential and a strongly degenerate coefficient, both vanishing at an interior point. This paper concludes the study of the Neumann case.

Źródło:

Opuscula Mathematica; 2019, 39, 2; 207-225
1232-9274
2300-6919

Pojawia się w:

Opuscula Mathematica

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 56.

Tytuł:

Spatial-Temporal Analysis of Rainfall West Java Indonesia Using Empirical Orthogonal Function based on Singular Value Decomposition

Autorzy:

Pribadi, Diantiny Mariam
Sumiati, Ira
Purwani, Sri

Powiązania:

https://bibliotekanauki.pl/articles/1031922.pdf

Data publikacji:

2020

Wydawca:

Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN

Tematy:

Empirical Orthogonal Function
Rainfall
Singular Value Decomposition
Spatial-Temporal

Opis:

Rainfall is one of the climate variables that have a significant influence, especially in supporting the activities of various sectors in tropical countries. Climate change is causing rainfall variability in Indonesia. However, the analysis of climate variable patterns is difficult because of the formation of a large matrix. Empirical Orthogonal Function (EOF) analysis can be used to reduce the dimensions of large data by maintaining as much variation as possible from the original data set. The method used in this study is through the Singular Value Decomposition (SVD) approach. The analysis shows that 98.50% of the total rainfall variance can be represented by four EOF modes. Analysis of the spatial pattern of EOF1 shows that rainfall is below average, while the other EOF modes show variations in rainfall.

Źródło:

World Scientific News; 2020, 140; 113-126
2392-2192

Pojawia się w:

World Scientific News

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 57.

Tytuł:

Multiple positive solutions to singular boundary value problems for superlinear second order FDEs

Autorzy:

Jiang, Daqing

Powiązania:

https://bibliotekanauki.pl/articles/1207893.pdf

Data publikacji:

2000

Wydawca:

Polska Akademia Nauk. Instytut Matematyczny PAN

Tematy:

superlinear
fixed point theorem
singular boundary value problem
existence

Opis:

We study the existence of positive solutions to the singular boundary value problem for a second-order FDE

⎧ u'' + q(t) f(t,u(w(t))) = 0, for almost all 0 < t < 1,
⎨ u(t) = ξ(t), a ≤ t ≤ 0,
⎩ u(t) = η(t), 1 ≤ t ≤ b,

where q(t) may be singular at t = 0 and t = 1, f(t,u) may be superlinear at u = ∞ and singular at u = 0.

Źródło:

Annales Polonici Mathematici; 2000, 75, 3; 257-270
0066-2216

Pojawia się w:

Annales Polonici Mathematici

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 58.

Tytuł:

A note on minimax rates of convergence in the Spektor-Lord-Willis problem

Autorzy:

Szkutnik, Z.

Powiązania:

https://bibliotekanauki.pl/articles/254773.pdf

Data publikacji:

2010

Wydawca:

Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH

Tematy:

poisson inverse problem
rate minimaxity
singular value decomposition
stereology

Opis:

In this note, attainable lower bounds are constructed for the convergence rates in a stereological problem of unfolding spheres size distribution from linear sections, which shows that a spectral type estimator is strictly rate minimax over some Sobolev-type classes of functions.

Źródło:

Opuscula Mathematica; 2010, 30, 2; 203-207
1232-9274
2300-6919

Pojawia się w:

Opuscula Mathematica

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

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Skocz do pozycji: 59.

Tytuł:

Singular continuous spectrum of half-line Schrodinger operators with point interactions on a sparse set

Autorzy:

Lotoreichik, V.

Powiązania:

https://bibliotekanauki.pl/articles/254871.pdf

Data publikacji:

2011

Wydawca:

Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH

Tematy:

half-line Schrodinger operators
delta-interactions
singular continuous spectrum

Opis:

We say that a discrete set X = {xn}n ∈ N0 on the half-line 0 = x0 < x1 < x2 < x3 < ⋅ ⋅ ⋅< xn < ⋅ ⋅ ⋅,< +∞ is sparse if the distances Δxn = xn+1-xn between neighbouring points satisfy the condition [formula]. In this paper half-line Schrödinger operators with point δ- and δ'- interactions on a sparse set are considered. Assuming that strengths of point interactions tend to ∞ we give simple sufficient conditions for such Schrödinger operators to have non-empty singular continuous spectrum and to have purely singular continuous spectrum, which coincides with R+.

Źródło:

Opuscula Mathematica; 2011, 31, 4; 615-628
1232-9274
2300-6919

Pojawia się w:

Opuscula Mathematica

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 60.

Tytuł:

Existence results for Kirchhoff type systems with singular nonlinearity

Autorzy:

Firouzjai, A.
Afrouzi, G. A.
Talebi, S.

Powiązania:

https://bibliotekanauki.pl/articles/254877.pdf

Data publikacji:

2018

Wydawca:

Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH

Tematy:

sub-supersolution
infinite semipositone systems
singular weights
Kirchhoff-type

Opis:

Using the method of sub-super solutions, we study the existence of positive solutions for a class of singular nonlinear semipositone systems involving nonlocal operator.

Źródło:

Opuscula Mathematica; 2018, 38, 2; 187-199
1232-9274
2300-6919

Pojawia się w:

Opuscula Mathematica

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 61.

Tytuł:

Generalized characteristic singular integral equation with Hilbert kernel

Autorzy:

Karczmarek, P.

Powiązania:

https://bibliotekanauki.pl/articles/255057.pdf

Data publikacji:

2008

Wydawca:

Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH

Tematy:

singular integral equation
characteristic equation
exact solution
Hilbert kernel

Opis:

In this paper an explicit solution of a generalized singular integral equation with a Hilbert kernel depending on indices of characteristic operators is presented.

Źródło:

Opuscula Mathematica; 2008, 28, 3; 287-294
1232-9274
2300-6919

Pojawia się w:

Opuscula Mathematica

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 62.

Tytuł:

Singular integral equation with a multiplicative Cauchy kernel in the half-plane

Autorzy:

Karczmarek, P.

Powiązania:

https://bibliotekanauki.pl/articles/255089.pdf

Data publikacji:

2008

Wydawca:

Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH

Tematy:

singular integral equation
exact solution
Cauchy kernel
multiplicative kernel

Opis:

In this paper the explicit solutions of singular integral equation with a multiplicative Cauchy kernel in the half-plane are presented.

Źródło:

Opuscula Mathematica; 2008, 28, 1; 63-72
1232-9274
2300-6919

Pojawia się w:

Opuscula Mathematica

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 63.

Tytuł:

A relation between the concepts of transposition, similarity, and symmetry, as well as matrix equations

Autorzy:

Kaczorek, Tadeusz

Powiązania:

https://bibliotekanauki.pl/articles/747820.pdf

Data publikacji:

2005

Wydawca:

Polskie Towarzystwo Matematyczne

Tematy:

Matrix equations and identities, Eigenvalues, singular values, and eigenvectors

Opis:

The author studies relationships among the notions of transpose, similarity, and symmetrization of matrices. It is shown that a square matrix is similar to its transpose, and that there exists a matrix that, simultaneously, carries this similarity transformation and symmetrizes the matrix. Furthermore, some equalities involving adjoint matrices are established as well. The proofs of the results are formulated for complex matrices, but they are valid also for other algebraically closed fields.

Źródło:

Mathematica Applicanda; 2005, 33, 47/06
1730-2668
2299-4009

Pojawia się w:

Mathematica Applicanda

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 64.

Tytuł:

Singular values of symptom observation matrix of a system in operation as indicators of system damage
Wartości szczególne symptomowej macierzy obserwacji eksploatowanego systemu mechanicznego jako wskaźniki zużycia

Autorzy:

Cempel, C.

Powiązania:

https://bibliotekanauki.pl/articles/328051.pdf

Data publikacji:

2011

Wydawca:

Polska Akademia Nauk. Polskie Towarzystwo Diagnostyki Technicznej PAN

Tematy:

stan maszyny
symptomowa macierz obserwacji
dekompozycja SVD
ewolucja wartości szczególnych
machine condition
symptom observation matrix
singular value decomposition
evolution of singular values

Opis:

The last paper of the present author [19] was concerned with multidimensional condition monitoring of the machines and the application of singular value decomposition (SVD). It was shown there, the immunity of singular values against uncontrolled load change, and they are also some measures of damage intensity. Following this, a simple model of singular value evolution has been proposed here and tested by means of three cases of real diagnostics in industry. It was found that postulated linear growth of singular value is good approximation of its real behavior and the same concerns the exponential growth of singular values product. Moreover this measures are sensitive to the redundancy of observation space and can depict clearly a lifetime when real damage in a monitored system starts. These properties seem to be much wanted in condition monitoring, so further investigations are planned.
Ostatnia praca autora [19] pokazuje zastosowanie rozkładu wartości szczególnych symptomowej macierzy obserwacji w diagnostyce maszyn. Pokazano tam, że ewolucja wartości szczególnych rozkładu w czasie życia maszyny jest niewrażliwa na wahania obciążenia roboczego systemu. Zatem w obecnej pracy zaproponowano liniowy model ewolucji wartości szczególnych i ekspotencjalny model dla ich iloczynu. Porównania tych modeli z rzeczywistym przebiegiem wartości szczególnych eksploatowanych maszyn pokazują, że dla przypadku liniowego zużycia jest to dobry model, natomiast często widać skoki poziomu w ewolucji wartości szczególnej. Może to świadczyć o pojawieniu się dodatkowego uszkodzenia, bądź o przejściu zużycia do bardziej intensywnej fazy rozwoju. Planuje się, zatem przeprowadzić dalsze badania celem wyjaśnienia szczegółowego zachowania wartości szczególnych.

Źródło:

Diagnostyka; 2011, 4(60); 27-38
1641-6414
2449-5220

Pojawia się w:

Diagnostyka

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 65.

Tytuł:

On 3D anticrack problem of thermoelectroelasticity

Autorzy:

Kaczyński, A.

Powiązania:

https://bibliotekanauki.pl/articles/387471.pdf

Data publikacji:

2018

Wydawca:

Politechnika Białostocka. Oficyna Wydawnicza Politechniki Białostockiej

Tematy:

thermoelectroelasticity
heat flow
anticrack
singular integral equation
thermal stress singularities

Opis:

A solution is presented for the static problem of thermoelectroelasticity involving a transversely isotropic space with a heat-insulated rigid sheet-like inclusion (anticrack) located in the isotropy plane. It is assumed that far from this defect the body is in a uniform heat flow perpendicular to the inclusion plane. Besides, considered is the case where the electric potential on the anticrack faces is equal to zero. Accurate results are obtained by constructing suitable potential solutions and reducing the thermoelectromechanical problem to its thermomechanical counterpart. The governing boundary integral equation for a planar anticrack of arbitrary shape is obtained in terms of a normal stress discontinuity. As an illustration, a closed-form solution is given and discussed for a circular rigid inclusion.

Źródło:

Acta Mechanica et Automatica; 2018, 12, 2; 109-114
1898-4088
2300-5319

Pojawia się w:

Acta Mechanica et Automatica

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 66.

Tytuł:

Doubly periodic cracks in the anisotropic medium with the account of contact of their faces

Autorzy:

Maksymovych, O.
Pasternak, I.
Sulym, H.
Kutsyk, S.

Powiązania:

https://bibliotekanauki.pl/articles/386627.pdf

Data publikacji:

2014

Wydawca:

Politechnika Białostocka. Oficyna Wydawnicza Politechniki Białostockiej

Tematy:

anisotropic
doubly periodic
singular integral equation
crack
anizotropia
dwuokresowość
pęknięcie

Opis:

The paper presents complex variable integral formulae and singular boundary integral equations for doubly periodic cracks in anisotropic elastic medium. It utilizes the numerical solution procedure, which accounts for the contact of crack faces and produce accurate results for SIF evaluation. It is shown that the account of contact effects significantly influence the SIF of doubly periodic curvilinear cracks both for isotropic and anisotropic materials.

Źródło:

Acta Mechanica et Automatica; 2014, 8, 3; 160-164
1898-4088
2300-5319

Pojawia się w:

Acta Mechanica et Automatica

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 67.

Tytuł:

Solution of a class of the first kind singular integral equation with multiplicative Cauchy kernel

Autorzy:

Wójcik, Paweł
Sheshko, Michail A.
Pylak, Dorota
Karczmarek, Paweł

Powiązania:

https://bibliotekanauki.pl/articles/747083.pdf

Data publikacji:

2012

Wydawca:

Uniwersytet Marii Curie-Skłodowskiej. Wydawnictwo Uniwersytetu Marii Curie-Skłodowskiej

Tematy:

Singular integral equations
Cauchy-type kernel
multiplicative kernel
logarithmic singularities

Opis:

In the present paper, we give the exact solutions of a singular equation with logarithmic singularities in two classes of functions and construct formulae for the approximate solutions.

Źródło:

Annales Universitatis Mariae Curie-Skłodowska, sectio A – Mathematica; 2012, 66, 2
0365-1029
2083-7402

Pojawia się w:

Annales Universitatis Mariae Curie-Skłodowska, sectio A – Mathematica

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 68.

Tytuł:

Stable or not stable? Recognizing surge based on the pressure signal

Autorzy:

Garcia, D.
Liśkiewicz, G.

Powiązania:

https://bibliotekanauki.pl/articles/175253.pdf

Data publikacji:

2016

Wydawca:

Polska Akademia Nauk. Czytelnia Czasopism PAN

Tematy:

singular spectrum analysis
nonlinear dynamics
statistical pattern recognition
compressor
surge

Opis:

The surge protection may be worth millions of dollars. This is typical price of a centrifugal compressor repair combined with additional cost of nonfunctionality of an industry employing it. This threat is normally secured by application of an antisurge systems. Typically they are activated at predefined working conditions when compressor mass flow rate approaches region affected by the surge. As a result those systems are vastly limiting its operational range usually by a desirable region where compressor attains large pressure ratio. Therefore, a modern antisurge systems are aiming at diminishing this tradeoff by reacting to the real pressure signal gathered at high frequency. This paper presents one of those methods employing singular spectrum analysis. This algorithm has not been widely used for this application, while it was shown herein that it may bring clear distinction between stable and nonstable working condition, even at presurge conditions. Hence in further perspective it may bring anti-surge protection quality, that was not met with another methods.

Źródło:

Transactions of the Institute of Fluid-Flow Machinery; 2016, 133; 55-68
0079-3205

Pojawia się w:

Transactions of the Institute of Fluid-Flow Machinery

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

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Skocz do pozycji: 69.

Tytuł:

Multi symptom condition monitoring of a critical mechanical systems as a first approach to design condition inference agent (CIA)

Autorzy:

Cempel, C.

Powiązania:

https://bibliotekanauki.pl/articles/328728.pdf

Data publikacji:

2004

Wydawca:

Polska Akademia Nauk. Polskie Towarzystwo Diagnostyki Technicznej PAN

Tematy:

machine condition monitoring
vibration
faults
singular values
condition inference agent

Opis:

The paper presents the introductory results in application to multi fault condition monitoring of mechanical systems in operation, in particular internal combustion engines. This generalization to multi dimensionality and multi fault condition monitoring is possible by utilizing transformed symptom observation matrix, and by successive application of singular value decomposition (SVD) and based on it principal component analysis (PCA). On this basis one can make full ex-traction of fault related information taken from symptom observation matrix, which can be created by traditional monitoring technology. Moreover, by SVD/PCA we can create some independent fault measures and indices, and of overall system condition. In another words, full utilization of SVD/PCA enable us to pass from multi dimensional - non orthogonal symptom space, to or-thogonal generalized fault space, of much reduced dimension. This seems to be important, as it can increase the scope and the reliability of condition monitoring of critical system in operation. It enables also to maximize the amount of condition related information, and to redesign the tradi-tional condition monitoring system. At the end of the paper some introductory consideration are presented leading to a design of Condition Inference Agent (CIA), which will enable to infer in real time on condition of critical objects in operation.

Źródło:

Diagnostyka; 2004, 30, T. 1; 91-96
1641-6414
2449-5220

Pojawia się w:

Diagnostyka

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 70.

Tytuł:

Dynamic Contraction Method approach to digital longitudinal aircraft flight controller design

Autorzy:

Czyba, Roman
Stajer, Lukasz

Powiązania:

https://bibliotekanauki.pl/articles/229293.pdf

Data publikacji:

2019

Wydawca:

Polska Akademia Nauk. Czytelnia Czasopism PAN

Tematy:

nonlinear systems
MIMO systems
aircraft control
digital controller
singular perturbation

Opis:

This paper presents the design of digital controller for longitudinal aircraft model basedon the Dynamic Contraction Method. The control task is formulated as a tracking problem of velocity and flight path angle, where decoupled output transients are accomplished in spite of incomplete information about varying parameters of the system and external disturbances. The design of digital controller based on the pseudo-continuous approach is presented, where the digital controller is the result of continuous-time controller discretization. A resulting output feedback controller has a simple form of a combination of low-order linear dynamical systems and a matrix whose entries depend nonlinearly on certain known process variables. Simulation results for an aircraft model confirm theoretical expectations.

Źródło:

Archives of Control Sciences; 2019, 29, 1; 97-109
1230-2384

Pojawia się w:

Archives of Control Sciences

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 71.

Tytuł:

Acoustic propagation in inhomogeneous fluids: regularization via the introduction of fine particles

Autorzy:

Jordan, P. M.

Powiązania:

https://bibliotekanauki.pl/articles/38440473.pdf

Data publikacji:

2020

Wydawca:

Instytut Podstawowych Problemów Techniki PAN

Tematy:

inhomogeneous fluids
Laplace transform
particle-laden flow
singular surface theory

Opis:

It is shown, using analytical methodologies, that the velocity field blow-up suffered by vertically ascending acoustic waves in an isothermal atmosphere can be eliminated via the introduction of fine particles. Assuming the inhomogeneous generalization of the particle-laden flow model known as the (linearized) Marble–Thompson model-1, it is established that bounded, exponentially decreasing, shock amplitudes can be obtained provided the mass fraction of particles exceeds a critical value, for which an exact expression is derived. Lastly, supporting numerical results are presented, special cases are discussed, and possible follow-on studies are noted.

Źródło:

Archives of Mechanics; 2020, 72, 1; 59-73
0373-2029

Pojawia się w:

Archives of Mechanics

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 72.

Tytuł:

Solutions of a class of singular linear systems of difference equations. Part 2

Autorzy:

Kanan, Asmaa M.

Powiązania:

https://bibliotekanauki.pl/articles/1030133.pdf

Data publikacji:

2020

Wydawca:

Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN

Tematy:

Drazin inverse
Moore-Penrose generalized inverse
Singular linear difference systems

Opis:

We extend results of Campbell of the linear systems of differential equations A x ̇+ Bx=f when A and B are rectangular, and results of Kanan of solution of a class of singular linear systems of difference equations A x_(n+1)+ Bx_n=f_n when A and B are square, to such systems of difference equations when A and B are rectangular. Explicit solutions of the last one are derived for several cases. One such is, when the matrix (λA+B) is one-to-one, another case is when such matrix is onto, for a scalar λ∈C. Also, explicit solutions are derived for the case that A is onto, and for the case that B is onto.

Źródło:

World Scientific News; 2020, 143; 127-138
2392-2192

Pojawia się w:

World Scientific News

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 73.

Tytuł:

On approach regions for the conjugate Poisson integral and singular integrals

Autorzy:

Ferrando, S.
Jones, R.
Reinhold, K.

Powiązania:

https://bibliotekanauki.pl/articles/1287340.pdf

Data publikacji:

1996

Wydawca:

Polska Akademia Nauk. Instytut Matematyczny PAN

Tematy:

cone condition
conjugate Poisson integral
singular integrals
ergodic Hilbert transform

Opis:

Let ũ denote the conjugate Poisson integral of a function $f ∈ L^{p}(ℝ)$. We give conditions on a region Ω so that $lim_{(v,ε)→(0,0)}_{(v,ε)∈Ω} ũ(x+v,ε) = Hf(x)$, the Hilbert transform of f at x, for a.e. x. We also consider more general Calderón-Zygmund singular integrals and give conditions on a set Ω so that $sup_{(v,r)∈Ω} |ʃ_{|t|>r} k(x+v-t)f(t)dt|$ is a bounded operator on $L^p$, 1 < p < ∞, and is weak (1,1).

Źródło:

Studia Mathematica; 1996, 120, 2; 169-182
0039-3223

Pojawia się w:

Studia Mathematica

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 74.

Tytuł:

A variant sharp estimate for multilinear singular integral operators

Autorzy:

Hu, Guoen
Yang, Dachun

Powiązania:

https://bibliotekanauki.pl/articles/1206036.pdf

Data publikacji:

2000

Wydawca:

Polska Akademia Nauk. Instytut Matematyczny PAN

Tematy:

multilinear singular integral operator
BMO
weighted norm inequality
sharp estimate

Opis:

We establish a variant sharp estimate for multilinear singular integral operators. As applications, we obtain the weighted norm inequalities on general weights and certain $Llog^{+}L$ type estimates for these multilinear operators.

Źródło:

Studia Mathematica; 2000, 141, 1; 25-22
0039-3223

Pojawia się w:

Studia Mathematica

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 75.

Tytuł:

Bang-bang controls in the singular perturbations limit

Autorzy:

Artstein, Z.

Powiązania:

https://bibliotekanauki.pl/articles/970546.pdf

Data publikacji:

2005

Wydawca:

Polska Akademia Nauk. Instytut Badań Systemowych PAN

Tematy:

zaburzenia osobliwe
miara Younga
bang-bang
singular perturbations
Young measures

Opis:

A general form of the dynamics obtained as a limit of trajectories of singularly perturbed linear control systems is presented. The limit trajectories are described in terms of probability measure-valued maps. This allows to determine the extent to which the bang-bang principle for linear control systems is carried over to the singular limit.

Źródło:

Control and Cybernetics; 2005, 34, 3; 645-663
0324-8569

Pojawia się w:

Control and Cybernetics

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 76.

Tytuł:

Improving the Consistency and Continuity of MODIS 8 Day Leaf Area Index Products

Autorzy:

Kandasamy, S.
Neveux, P.
Verger, A.
Buis, S.
Weiss, M.
Baret, F.

Powiązania:

https://bibliotekanauki.pl/articles/227345.pdf

Data publikacji:

2012

Wydawca:

Polska Akademia Nauk. Czytelnia Czasopism PAN

Tematy:

iterative caterpillar singular spectrum analysis
MODIS
LAI
gap-filling
smoothing

Opis:

Time Series Analysis of Leaf Area Index (LAI) is vital to the understanding of global vegetation dynamics. The LAI time series derived from satellite observations are usually not complete and noisy due to cloud contamination and uncertainties in the retrieval techniques. In this paper, the continuity and consistency of the MODIS 8 day LAI products are improved using a method based on Caterpillar Singular Spectrum Analysis. The proposed method is compared with other standard methods: Savitzky-Golay filter, Empirical Mode Decomposition, Low Pass filtering and Asymmetric Gaussian fitting. The experiment demonstrates the smoothing and gapfilling ability of the developed method, which is more robust across the biomes both in terms of root mean square error metrics and bias metrics as compared to the standard methods.

Źródło:

International Journal of Electronics and Telecommunications; 2012, 58, 2; 141-146
2300-1933

Pojawia się w:

International Journal of Electronics and Telecommunications

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 77.

Tytuł:

Nadzwyczajne formy notyfikacji dekretu poszczególnego (kan. 55–56 KPK)
Extraordinary forms of notification of singular decrees (cann. 55-56 CIC)

Autorzy:

Dzierżon, Ginter

Powiązania:

https://bibliotekanauki.pl/articles/502652.pdf

Data publikacji:

2016

Wydawca:

Wyższe Seminarium Duchowne w Łodzi

Tematy:

prawo kościelne
notyfikacja
dekret poszczególny
ecclesiastical law
notification
singular decree

Opis:

The author of the presented article carried out a thorough interpretation of cann. 55 and 56 CIC. His analyses show that the conditions specified in can. 55 CIC are required in order to make a decree fair but are not necessary to make it valid. The author claims that despite the nature of these requirements one should not treat them disrespectfully in their administrative practice. This is because the written form of a decree guarantees its justice and gives its addressees the right to defense. First and foremost, however, a written record is necessary for evidential purposes. The author believes that a form equivalent to a notification described in can. 56 CIC complements other forms codified in cann. 54 and 55 CIC. It is his opinion that introducing this kind of solutions based on mechanisms of fiction is justifiable since issuing decrees often generates tensions between the parties involved. He understands that the functioning of such solutions ensures the effectiveness of these administrative acts even in specific situations.

Źródło:

Łódzkie Studia Teologiczne; 2016, 25, 2; 71-78
1231-1634

Pojawia się w:

Łódzkie Studia Teologiczne

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 78.

Tytuł:

On the blowing up solutions of the 4-d general q-Kuramoto-Sivashinsky equation with exponentially “dominated” nonlinearity and singular weight

Autorzy:

Baraket, Sami
Mahdaoui, Safia
Ouni, Taieb

Powiązania:

https://bibliotekanauki.pl/articles/29519212.pdf

Data publikacji:

2023

Wydawca:

Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH

Tematy:

singular limits
Green’s function
nonlinearity
gradient
nonlinear domain decomposition method

Opis:

Let Ω be a bounded domain in $ \mathbb{R}^4 $ with smooth boundary and let $ x^1, x^2, . . . , x^m $ be m-points in Ω. We are concerned with the problem $ \Delta^2 u - H(x, u, D^k u)=\rho^4 \prod_{i=1}^n | x - p_i |^{4 \alpha_i } f(x)g(u), $ where the principal term is the bi-Laplacian operator, $ H(x, u, D^k u)$ is a functional which grows with respect to $ Du $ at most like $ |Du|^q, 1 ≤ q ≤ 4, f : Ω → [0,+∞[ $ is a smooth function satisfying f(pi) > 0 for any i = 1, . . . , n, $ α_i $ are positives numbers and $ g : \mathbb{R} → [0,+∞[ $ satisfy $ |g(u)| ≤ ce^u $. In this paper, we give sufficient conditions for existence of a family of positive weak solutions $ (u_ρ)_{ρ>0} $ in Ω under Navier boundary conditions u = Δu = 0 on ∂Ω. The solutions we constructed are singular as the parameters ρ tends to 0, when the set of concentration $ S = {x^1, . . . , x^m} ⊂ Ω $ and the set $ Λ := {p_1, . . . , p_n} ⊂ Ω $ are not necessarily disjoint. The proof is mainly based on nonlinear domain decomposition method.

Źródło:

Opuscula Mathematica; 2023, 43, 1; 5-18
1232-9274
2300-6919

Pojawia się w:

Opuscula Mathematica

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 79.

Tytuł:

Singular integral models for p-hyponormal operators and the Riemann-Hilbert problem

Autorzy:

Chō, Muneo
Huruya, Tadasi
Itoh, Masuo

Powiązania:

https://bibliotekanauki.pl/articles/1218219.pdf

Data publikacji:

1998

Wydawca:

Polska Akademia Nauk. Instytut Matematyczny PAN

Tematy:

Hilbert space
p-hyponormal operator
singular integral model
Riemann-Hilbert problem

Opis:

The purpose of this paper is to give singular integral models for p-hyponormal operators and apply them to the Riemann-Hilbert problem.

Źródło:

Studia Mathematica; 1998, 130, 3; 213-221
0039-3223

Pojawia się w:

Studia Mathematica

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 80.

Tytuł:

On singular arcs in nonsmooth optimal control

Autorzy:

Oberle, H. J.
Rosendahl, R.

Powiązania:

https://bibliotekanauki.pl/articles/969559.pdf

Data publikacji:

2008

Wydawca:

Polska Akademia Nauk. Instytut Badań Systemowych PAN

Tematy:

nonsmooth optimal control problems
necessary conditions
singular state subarcs
Zermelo's problem

Opis:

In this paper we consider general optimal control problems (OCP) which are characterized by a nonsmooth ordinary state differential equation. However, we allow only mild types of nonsmoothness. More precisely, we assume that the right-hand side of the state equation is piecewise smooth and that the switching points, which separate these pieces, are determined as points, where a state-and possibly control-dependent (smooth) switching function changes sign. For this kind of optimal control problems necessary optimality conditions are developed. Attention is paid to the situation when the switching function vanishes identically along a nontrivial subarc. Such subarcs, which we call singular state subarcs, are investigated with respect to necessary conditions and to junction conditions. In extension to earlier results of the authors, Oberle and Rosendhal (2006), in this paper nonsmooth OCPs are considered with respect to the order of the switching function. Especially, the case of a zero-order switching function is included and examples of order zero, one and two are treated.

Źródło:

Control and Cybernetics; 2008, 37, 2; 429-450
0324-8569

Pojawia się w:

Control and Cybernetics

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 81.

Tytuł:

Sufficient optimality conditions for a bang-singular extremal in the minimum time problem

Autorzy:

Poggiolini, L.
Stefani, G.

Powiązania:

https://bibliotekanauki.pl/articles/969613.pdf

Data publikacji:

2008

Wydawca:

Polska Akademia Nauk. Instytut Badań Systemowych PAN

Tematy:

minimum time
second order sufficient conditions
bang-singular arc
Hamiltonian formalism

Opis:

The paper gives second order sufficient conditions for the strong local optimality of a bang-singular extremal in a minimum time problem. The conditions are given in terms of regularity assumptions on the extremal and of the coercivity of the extended second variation associated to the minimum time problem with fixed end-points on the singular arc. The conditions are close to the necessary ones in the usual sense, namely we require strict inequalities where necessary conditions have mild inequalities.

Źródło:

Control and Cybernetics; 2008, 37, 2; 469-490
0324-8569

Pojawia się w:

Control and Cybernetics

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 82.

Tytuł:

Generalized powers and measures

Autorzy:

Burdak, Zbigniew
Kosiek, Marek
Pagacz, Patryk
Rudol, Krzysztof
Słociński, Marek

Powiązania:

https://bibliotekanauki.pl/articles/2048973.pdf

Data publikacji:

2021

Wydawca:

Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH

Tematy:

representing measures
Szegö-singular measure
compatible pair of isometries
spectral measure

Opis:

Using the winding of measures on torus in “rational directions” special classes of unitary operators and pairs of isometries are defined. This provides nontrivial examples of generalized powers. Operators related to winding Szegö-singular measures are shown to have specific properties of their invariant subspaces.

Źródło:

Opuscula Mathematica; 2021, 41, 6; 747-754
1232-9274
2300-6919

Pojawia się w:

Opuscula Mathematica

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

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Skocz do pozycji: 83.

Tytuł:

Study of the anti-plane problem of a Dugdale-Barenblatt crack in a welded strip using the integral equation method

Autorzy:

Chaouche, Amine Brick
Ferdjani, Hicheme
Tala-Ighil, Nacer

Powiązania:

https://bibliotekanauki.pl/articles/279531.pdf

Data publikacji:

2019

Wydawca:

Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej

Tematy:

crack
Dugdale-Barenblatt model
weld joint
singular integral equation
infinite strip

Opis:

The elasto-static anti-plane problem of a Dugdale-Barenblatt crack in a welded infinite strip is formulated in terms of a singular integral equation (SIE). The weld joint is modeled as a tri-material structure: the weld metal (WM), the base metal (BM) and the heat-affected zone (HAZ). The HAZ is modeled with an exponentially variable shear modulus. The SIE is solved using Tchebychev polynomials. The influence of the elastic mismatching (the ratio between the shear modulus of WM and BM) and width of the HAZ on the fracture load and on the crack propagation is investigated.

Źródło:

Journal of Theoretical and Applied Mechanics; 2019, 57, 2; 475-487
1429-2955

Pojawia się w:

Journal of Theoretical and Applied Mechanics

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 84.

Tytuł:

Interaction between a stratified elastic half-space and an irregular base allowing for the intercontact gas
Oddziaływanie sprężystej półprzestrzeni warstwowej na sztywną przeszkodę oddzielona szczeliną wypełnioną gazem

Autorzy:

Machyshyn, I.
Nagórko, W.

Powiązania:

https://bibliotekanauki.pl/articles/280251.pdf

Data publikacji:

2003

Wydawca:

Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej

Tematy:

contact problem
laminated half-space
gas
complex potentials
singular integral equations

Opis:

The paper is devoted to the investigation of contact interaction of a laminated half-space and a rigid body with a smooth cylindrical depression under conditions of plane deformation allowing for an intercontact ideal gas. To describe the homogenized model of the laminated body with microlocal parameters and to describe the behavior of the gas - equations of ideal gas state are used. Applying the method of comlex potentials the problem is reduced to the singular integral equation for the height of intercontact gap and its solution is obtained in a closed form. To find the lenght of the gap, its volume and the gas pressure a system of three equations is derived. With the aid of this system the dependence of the external loading and amount of the gas in the gap on the contact pressure and geometrical parameters of the gap is analyzed.
W pracy analizuje się oddziaływanie sprężystej półprzestrzeni warstwowo-niejednorodnej na ciało sztywne z walcową szczeliną wypełnioną gazem. Półprzestrzeń sprężystą poddaje się homogenizacji mikrolokalnej, a do rozwiązania otrzymanych równań modelowych stosuje się metodę potencjałów zespolonych. Analizowany problem sprowadza się do poszukiwania rozwiązania równania całkowego. W pracy uzyskuje się rozwiązania w postaci zamkniętej oraz przeprowadza analizę numeryczną zależności rozwartości szczeliny oraz jej objętości od obciążenia zewnętrznego.

Źródło:

Journal of Theoretical and Applied Mechanics; 2003, 41, 2; 271-288
1429-2955

Pojawia się w:

Journal of Theoretical and Applied Mechanics

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

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Skocz do pozycji: 85.

Tytuł:

The Relationship Between the Infinite Eigenvalue Assignment for Singular Systems and the Solvability of Polynomial Matrix Equations

Autorzy:

Kaczorek, T.

Powiązania:

https://bibliotekanauki.pl/articles/908199.pdf

Data publikacji:

2003

Wydawca:

Uniwersytet Zielonogórski. Oficyna Wydawnicza

Tematy:

automatyka
robotyka
assignment
infinite eigenvalue
singular
polynomial matrix equation
system
reliationship

Opis:

Two related problems, namely the problem of the infinite eigenvalue assignment and that of the solvability of polynomial matrix equations are considered. Necessary and sufficient conditions for the existence of solutions to both the problems are established. The relationships between the problems are discussed and some applications from the field of the perfect observer design for singular linear systems are presented.

Źródło:

International Journal of Applied Mathematics and Computer Science; 2003, 13, 2; 161-167
1641-876X
2083-8492

Pojawia się w:

International Journal of Applied Mathematics and Computer Science

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

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Skocz do pozycji: 86.

Tytuł:

Strong sequences and partition relations

Autorzy:

Jureczko, Joanna

Powiązania:

https://bibliotekanauki.pl/articles/744632.pdf

Data publikacji:

2017-12-01

Wydawca:

Uniwersytet Pedagogiczny im. Komisji Edukacji Narodowej w Krakowie

Tematy:

Strong sequences
Erdös-Rado theorem
partition relations
inaccessible cardinals
singular cardinals

Opis:

The first result in partition relations topic belongs to Ramsey (1930). Since that this topic has been still explored. Probably the most famous partition theorem is Erdös-Rado theorem (1956). On the other hand in 60’s of the last century Efimov introduced strong sequences method, which was used for proving some famous theorems in dyadic spaces. The aim of this paper is to generalize theorem on strong sequences and to show that it is equivalent to generalized version of well-known Erdös-Rado theorem. It will be also shown that this equivalence holds for singulars. Some applications and conclusions will be presented too.

Źródło:

Annales Universitatis Paedagogicae Cracoviensis. Studia Mathematica; 2017, 16
2300-133X

Pojawia się w:

Annales Universitatis Paedagogicae Cracoviensis. Studia Mathematica

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

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Skocz do pozycji: 87.

Tytuł:

Investigation of the dynamics of singular protected systems

Autorzy:

Naumeyko, I.
Alja'afreh, M.

Powiązania:

https://bibliotekanauki.pl/articles/411040.pdf

Data publikacji:

2016

Wydawca:

Polska Akademia Nauk. Oddział w Lublinie PAN

Tematy:

"Man-Machine-Environment" model
non-linear system
singular equations
asymptotic
linearization

Opis:

The analysis of asymptotic representations of the systems protected from harmful influences is carried out. Various types of general models of the "manmachineenvironment" with protection are considered. Each of them adequately describes some of the practically important qualities of the object, and they all together describe the object in terms of its safe operation. The dynamic properties of complex ergonomic systems, presented in the form of systems of differential equations with a small parameter at the derivative are investigated The methods of reducing the impact on the person of harmful factors are theoretically substantiated. The dynamic protection response speed is considered to be significantly greater than the harmful factor production rate. Numerical solution of the general problem and the analytical solution for autonomous case is obtained for harmful effects. By using asymptotic the system of equations has been solved in closed form not only for autonomous case, but also for parameters smoothly changing in time. The estimates of the cost of protection was obtained for the various cost-functionals and for different functions in the right-hand side of the equation describing the dynamics of protection. To assess the accuracy of model calculations and for graphic representation of the results mathematical package MAXIMA is used.

Źródło:

ECONTECHMOD : An International Quarterly Journal on Economics of Technology and Modelling Processes; 2016, 5, 4; 37-42
2084-5715

Pojawia się w:

ECONTECHMOD : An International Quarterly Journal on Economics of Technology and Modelling Processes

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

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Skocz do pozycji: 88.

Tytuł:

Singular Vectors in Acoustic Simulation Tests of St. Paul the Apostle Church in Bochnia

Autorzy:

Kosała, K.

Powiązania:

https://bibliotekanauki.pl/articles/177255.pdf

Data publikacji:

2012

Wydawca:

Polska Akademia Nauk. Czytelnia Czasopism PAN

Tematy:

acoustic quality
index method
churches
singular value decomposition (SVD)
acoustics adaptation

Opis:

A new approach to acoustic quality assessment of churches during simulation tests is proposed in the article. The numerical global index, based on four partial indices: reverberation, speech intelligibility, music sound index and a proposed new one – sound strength index, assesses the acoustic parameters of the model of the tested church in a complex manner. The global single number index was obtained from 17 simulations of acoustic adaptation options of the investigated church’s interior. The equation of the approximate global index has been obtained by means of singular vectors, obtained from Singular Value Decomposition (SVD) of the Index Observation Matrix of Simulation Variants (IOMSV). The weights of four partial indices and a universal equation of the global index have been calculated using the SVD technique to solve the problem of correlated acoustical parameters. The global index may be a helpful tool during simulation tests of acoustic quality assessment of churches. The proposed final equation of the global index does not require knowledge of the SVD technique and the values of acoustic parameters preferred for churches. Therefore the methodology proposed is easily applicable.

Źródło:

Archives of Acoustics; 2012, 37, 1; 23-30
0137-5075

Pojawia się w:

Archives of Acoustics

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

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Skocz do pozycji: 89.

Tytuł:

A Tikhonov-type theorem for abstract parabolic differential inclusions in Banach spaces

Autorzy:

Gudovich, Anastasie
Kamenski, Mikhail
Nistri, Paolo

Powiązania:

https://bibliotekanauki.pl/articles/729318.pdf

Data publikacji:

2001

Wydawca:

Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii

Tematy:

singular perturbations
differential inclusions
analytic semigroups
multivalued compact operators
Lipschitz selections

Opis:

We consider a class of singularly perturbed systems of semilinear parabolic differential inclusions in infinite dimensional spaces. For such a class we prove a Tikhonov-type theorem for a suitably defined subset of the set of all solutions for ε ≥ 0, where ε is the perturbation parameter. Specifically, assuming the existence of a Lipschitz selector of the involved multivalued maps we can define a nonempty subset $Z_L(ε)$ of the solution set of the singularly perturbed system. This subset is the set of the Hölder continuous solutions defined in [0,d], d > 0 with prescribed exponent and constant L. We show that $Z_L(ε)$ is uppersemicontinuous at ε = 0 in the C[0,d]×C[δ,d] topology for any δ ∈ (0,d].

Źródło:

Discussiones Mathematicae, Differential Inclusions, Control and Optimization; 2001, 21, 2; 207-234
1509-9407

Pojawia się w:

Discussiones Mathematicae, Differential Inclusions, Control and Optimization

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

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Skocz do pozycji: 90.

Tytuł:

Comparison of five SVD-based algorithms for calibration of spectrophotometric analyzers

Autorzy:

Wagner, J.
Morawski, R. Z.
Miękina, A.

Powiązania:

https://bibliotekanauki.pl/articles/220564.pdf

Data publikacji:

2014

Wydawca:

Polska Akademia Nauk. Czytelnia Czasopism PAN

Tematy:

spectrophotometry
chemometrics
singular value decomposition
regularisation
food analysis
edible oils analysis

Opis:

Spectrophotometry is an analytical technique of increasing importance for the food industry, applied i.a. in the quantitative assessment of the composition of mixtures. Since the absorbance data acquired by means of a spectrophotometer are highly correlated, the problem of calibration of a spectrophotometric analyzer is, as a rule, numerically ill-conditioned, and advanced data-processing methods must be frequently applied to attain an acceptable level of measurement uncertainty. This paper contains a description of four algorithms for calibration of spectrophotometric analyzers, based on the singular value decomposition (SVD) of matrices, as well as the results of their comparison - in terms of measurement uncertainty and computational complexity - with a reference algorithm based on the estimator of ordinary least squares. The comparison is carried out using an extensive collection of semi-synthetic data representative of trinary mixtures of edible oils. The results of that comparison show the superiority of an algorithm of calibration based on the truncated SVD combined with a signal-to-noise ratio used as a criterion for the selection of regularisation parameters - with respect to other SVD-based algorithms of calibration.

Źródło:

Metrology and Measurement Systems; 2014, 21, 2; 191-204
0860-8229

Pojawia się w:

Metrology and Measurement Systems

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 91.

Tytuł:

Admissibility tests for multidimensional singular fractional continuous-time models

Autorzy:

Benyettou, Kamel
Bouagada, Djillali

Powiązania:

https://bibliotekanauki.pl/articles/2175103.pdf

Data publikacji:

2022

Wydawca:

Polska Akademia Nauk. Czytelnia Czasopism PAN

Tematy:

singular Roesser model
fractional systems
multidimensional systems
linear matrix inequalities
admissibility

Opis:

In this paper we present and discuss a new class of singular fractional systems in a multidimensional state space described by the Roesser continuous-time models. The necessary and sufficient conditions for the asymptotic stability and admissibility by the use of linear matrix inequalities are established. All the obtained results are simulated by some numerical examples to show the applicability and accuracy of our approach.

Źródło:

Archives of Control Sciences; 2022, 32, 3; 607--625
1230-2384

Pojawia się w:

Archives of Control Sciences

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 92.

Tytuł:

The Number of P-Vertices of Singular Acyclic Matrices: An Inverse Problem

Autorzy:

Du, Zhibin
da Fonseca, Carlos M.

Powiązania:

https://bibliotekanauki.pl/articles/31804164.pdf

Data publikacji:

2020-05-01

Wydawca:

Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii

Tematy:

trees
acyclic matrices
singular
multiplicity of eigenvalues
P-set
P-vertices

Opis:

Let A be a real symmetric matrix. If after we delete a row and a column of the same index, the nullity increases by one, we call that index a P-vertex of A. When A is an n × n singular acyclic matrix, it is known that the maximum number of P-vertices is n − 2. If T is the underlying tree of A, we will show that for any integer number k ∈ {0, 1, . . ., n − 2}, there is a (singular) matrix whose graph is T and with k P-vertices. We will provide illustrative examples.

Źródło:

Discussiones Mathematicae Graph Theory; 2020, 40, 2; 525-532
2083-5892

Pojawia się w:

Discussiones Mathematicae Graph Theory

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

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Skocz do pozycji: 93.

Tytuł:

Stability analysis of variational inequalities for bang-singular-bang controls

Autorzy:

Felgenhauer, U.

Powiązania:

https://bibliotekanauki.pl/articles/206215.pdf

Data publikacji:

2013

Wydawca:

Polska Akademia Nauk. Instytut Badań Systemowych PAN

Tematy:

parametric optimal control problems bang-singular control structure
approximation of extremals

Opis:

The paper is related to parameter dependent optimal control problems for control-affine systems. The case of scalar reference control with bang-singular-bang structure is considered. The analysis starts from a variational inequality (VI) formulation of Pontryagin’s Maximum Principle. In a first step, under appropriate higher-order sufficient optimality conditions, the existence of solutions for the linearized problem (LVI) is proven. In a second step, for a certain class of right-hand side perturbation, it is show that the controls from LVI have bang-singular-bang structure and, in L₁ topology, depend Lipschitz continuously on the data. Applying finally a common fixed-point approach to VI, the results are brought together to obtain existence and structural stability results for extremals of the original control problem under parameter perturbation.

Źródło:

Control and Cybernetics; 2013, 42, 3; 557-592
0324-8569

Pojawia się w:

Control and Cybernetics

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 94.

Tytuł:

Mathematical modelling of stationary thermoelastic state for a plate with periodic system of inclusions and cracks

Autorzy:

Zelenyak, Volodymyr

Powiązania:

https://bibliotekanauki.pl/articles/387384.pdf

Data publikacji:

2019

Wydawca:

Politechnika Białostocka. Oficyna Wydawnicza Politechniki Białostockiej

Tematy:

stress intensity factor
singular integral equation
inclusion
heat conduction
thermoelasticity
crack

Opis:

Two-dimensional stationary problem of heat conduction and thermoelasticity for infinite elastic body containing periodic system of inclusions and cracks is considered. Solution of the problem is constructed using the method of singular integral equations (SIEs). The numerical solution of the system integral equations are obtained by the method of mechanical quadrature for a plate heated by a heat flow, containing periodic system elliptic inclusions and thermally insulated cracks. There are obtained graphic dependences of stress intensity factors (SIFs), which characterise the distribution of intensity of stresses at the tops of a crack, depending on the length of crack, elastic and thermoelastic characteristics inclusion, relative position of crack and inclusion.

Źródło:

Acta Mechanica et Automatica; 2019, 13, 1; 11-15
1898-4088
2300-5319

Pojawia się w:

Acta Mechanica et Automatica

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

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Skocz do pozycji: 95.

Tytuł:

Dynamic balance research of protected systems

Autorzy:

Naumeyko, I.
Alja'afreh, M.

Powiązania:

https://bibliotekanauki.pl/articles/411213.pdf

Data publikacji:

2015

Wydawca:

Polska Akademia Nauk. Oddział w Lublinie PAN

Tematy:

Non-linear system
singular points
eigenvalues
asymptotic behavior
first approximation
linearization

Opis:

The dynamic models of the complex ergatic objects' behavior, presented in the form of differentia equations and their systems were studied. The stability and other properties are researched. The methods of analysis and reduce of harmful factors and their impact on people were theoretically proved. The methods of analysis and critical points removal in dynamic models of hazards distribution are offered. The object of study is the system of the harmful external factors protection. Subject of research is the system of two nonlinear differential equations as a model of technical systems with protection. The object of protection is described by logistic equation. and defense system - by non-linear differential equation with a security functions of rather general form. This paper describes critical modes analysis and stationary states’ stability of protected systems with harmful influences. Numerical solution of general problem and also the analytical solution for the case of fixed expected harmful effects have been obtained. Various types of general models for "Man-machine-environment" systems were studied. Each of describes some kind of the practically important quality of object in an appropriate way. And All together they describe the object in terms of it’s safe operation. Their further detailing process results to either well-known, or some new subsystems’ models. Systems with "fast" protection at a relatively slow dynamics of the object were studied. This leads to the models with small parameter and asymptotic solutions of differentia equations. Some estimates for protection cost in different price-functional and for different functions in the right part of equation, which describes the dynamics of defense were obtained. For calculations, analysis and graphical representations some of mathematical packages was applied.

Źródło:

ECONTECHMOD : An International Quarterly Journal on Economics of Technology and Modelling Processes; 2015, 4, 3; 85-90
2084-5715

Pojawia się w:

ECONTECHMOD : An International Quarterly Journal on Economics of Technology and Modelling Processes

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

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Skocz do pozycji: 96.

Tytuł:

Constraints and gauge relations in the Lagrangian formalism

Autorzy:

Lam-Estrada, P.
López-Bonilla, J.
López-Vázquez, R.
Vidal-Beltrán, S.

Powiązania:

https://bibliotekanauki.pl/articles/1178075.pdf

Data publikacji:

2018

Wydawca:

Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN

Tematy:

Gauge identities
Genuine constraints
Local symmetries
Noether’s theorem
Singular Lagrangians

Opis:

For several Lagrangians we show that their local symmetries can be obtained from the associated Euler-Lagrange equations, and we exhibit the explicit presence of the genuine constraints into gauge identities. We also employ the Lanczos approach to Noether’s theorem to give connections between the genuine constraints and their time derivatives. Besides, it is evident that the Hamiltonian secondary and tertiary constraints have relationship with the genuine constraints.

Źródło:

World Scientific News; 2018, 95; 215-223
2392-2192

Pojawia się w:

World Scientific News

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 97.

Tytuł:

On solutions of integral equations with analytic kernels and rotations

Autorzy:

Nguyen, Mau
Nguyen, Tuan

Powiązania:

https://bibliotekanauki.pl/articles/1311183.pdf

Data publikacji:

1996

Wydawca:

Polska Akademia Nauk. Instytut Matematyczny PAN

Tematy:

integral operators
singular integral equations
algebraic operators
Riemann boundary value problems

Opis:

We deal with a class of integral equations on the unit circle in the complex plane with a regular part and with rotations of the form (*)     x(t) + a(t)(Tx)(t) = b(t), where $T = M_{n₁,k₁} ... M_{n_m,k_m}$ and $M_{n_j,k_j}$ are of the form (3) below. We prove that under some assumptions on analytic continuation of the given functions, (*) is a singular integral equation for m odd and is a Fredholm equation for m even. Further, we prove that T is an algebraic operator with characteristic polynomial $P_T(t) = t³ - t$. By means of the Riemann boundary value problems, we give an algebraic method to obtain all solutions of equation (*) in closed form.

Źródło:

Annales Polonici Mathematici; 1996, 63, 3; 293-300
0066-2216

Pojawia się w:

Annales Polonici Mathematici

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 98.

Tytuł:

A Bolza optimal synthesis problem for singular estimate control systems

Autorzy:

Lasiecka, I.
Tuffaha, A.

Powiązania:

https://bibliotekanauki.pl/articles/970760.pdf

Data publikacji:

2009

Wydawca:

Polska Akademia Nauk. Instytut Badań Systemowych PAN

Tematy:

Bolza problem
Riccati equation
singular estimate control systems
fluid-structure interaction

Opis:

Bolza problem governed by PDE control systems with unbounded controls is considered. The motivating example is fluid structure interaction model with boundary-interface controls. The aim of the work is to provide optimal feedback synthesis associated with well denned gain operator constructed from the Riccati equation. The dynamics considered is of mixed parabolic-hyperbolic type which prevents applicability of tools developed earlier for analytic semigroups. It is shown, however, that the control operator along with the generator of the semigroup under consideration satisfy singular estimate referred to as Revisited Singular Estimate (RSE). This estimate, which measures "unboundedness" of control actions, is a generalization and a weaker form of Singular Estimate (SE) treated in the past literature. The main result of the paper provides Riccati theory developed for this new class of control systems labeled as RSECS (Revisited Singular Estimate Control Systems). The important feature is that the gain operator, constructed via Riccati operator, is consistent with the optimal feedback synthesis. The gain operator, though unbounded, has a controlled algebraically singularity at the terminal point. This enables one to establish well-posedness of the Riccati solutions and of the optimal feedback representation. An application of the theoretical framework to boundary control of a fluid-structure interaction model is given.

Źródło:

Control and Cybernetics; 2009, 38, 4B; 1429-1460
0324-8569

Pojawia się w:

Control and Cybernetics

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 99.

Tytuł:

Existence and uniqueness results for fractional differential equations with boundary value conditions

Autorzy:

Lv, L.
Wang, J.
Wei, W.

Powiązania:

https://bibliotekanauki.pl/articles/254863.pdf

Data publikacji:

2011

Wydawca:

Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH

Tematy:

fractional differential equations
boundary value conditions
singular Gronwall inequality
existence
uniqueness

Opis:

In this paper, we study the existence and uniqueness of fractional differential equations with boundary value conditions. A new generalized singular type Gronwall inequality is given to obtain important a priori bounds. Existence and uniqueness results of solutions are established by virtue of fractional calculus and fixed point method under some weak conditions. An example is given to illustrate the results.

Źródło:

Opuscula Mathematica; 2011, 31, 4; 629-643
1232-9274
2300-6919

Pojawia się w:

Opuscula Mathematica

Dostawca treści:

Biblioteka Nauki

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Skocz do pozycji: 100.

Tytuł:

Unfolding spheres size distribution from linear sections with B-splines and EMDS algorithm

Autorzy:

Szkutnik, Z.

Powiązania:

https://bibliotekanauki.pl/articles/255515.pdf

Data publikacji:

2007

Wydawca:

Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH

Tematy:

inverse problem
singular value expansion
stereology
discretization
quasi-maximum likelihood estimator

Opis:

The stereological problem of unfolding spheres size distribution from linear sections is formulated as a problem of inverse estimation of a Poisson process intensity function. A singular value expansion of the corresponding integral operator is given. The theory of recently proposed B-spline sieved quasi-maximum likelihood estimators is modified to make it applicable to the current problem. Strong L2-consistency is proved and convergence rates are given. The estimators are implemented with the recently proposed EMDS algorithm. Promising performance of this new methodology in finite samples is illustrated with a numerical example. Data grouping effects are also discussed.

Źródło:

Opuscula Mathematica; 2007, 27, 1; 151-165
1232-9274
2300-6919

Pojawia się w:

Opuscula Mathematica

Dostawca treści:

Biblioteka Nauki

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