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39702. Unicyclic graphs with bicyclic inverses
- Creator:
- Panda, Swarup Kumar
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- matematika, mathematics, adjacency matrix, unicyclic graph, bicyclic graph, inverse graph, perfect matching, 13, and 51
- Language:
- English
- Description:
- A graph is nonsingular if its adjacency matrix $A(G)$ is nonsingular. The inverse of a nonsingular graph $G$ is a graph whose adjacency matrix is similar to $A(G)^{-1}$ via a particular type of similarity. Let $\mathcal{H}$ denote the class of connected bipartite graphs with unique perfect matchings. Tifenbach and Kirkland (2009) characterized the unicyclic graphs in $\mathcal{H}$ which possess unicyclic inverses. We present a characterization of unicyclic graphs in $\mathcal{H}$ which possess bicyclic inverses., Swarup Kumar Panda., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
39703. Unification and the myth of purely reductive understanding
- Creator:
- Shaffer, Michael J.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- explanation, reduction, simplicity, scientific understanding, and unification
- Language:
- Slovak
- Description:
- In this paper significant challenges are raised with respect to the view that explanation essentially involves unification. These objections are raised specifically with respect to the well-known versions of unificationism developed and defended by Michael Friedman and Philip Kitcher. The objections involve the explanatory regress argument and the concepts of reduction and scientific understanding. Essentially, the contention made here is that these versions of unificationism wrongly assume that reduction secures understanding.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
39704. Uniform a priori estimates for discrete solution of nonlinear tensor diffusion equation in image processing
- Creator:
- Drblíková, Olga
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- funite volume method, diamond-cell method, image processing, nonlinear parabolic equation, and tensor diffusion
- Language:
- English
- Description:
- This paper concerns with the finite volume scheme for nonlinear tensor diffusion in image processing. First we provide some basic information on this type of diffusion including a construction of its diffusion tensor. Then we derive a semi-implicit scheme with the help of so-called diamond-cell method (see \cite{Coirier1} and \cite{Coirier2}). Further, we prove existence and uniqueness of a discrete solution given by our scheme. The proof is based on a gradient bound in the tangential direction by a gradient in normal direction. Moreover, the proofs of L2(Ω) - a priori estimates for our discrete solution are given. Finally we present our computational results.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
39705. Uniform controllability for the beam equation with vanishing structural damping
- Creator:
- Bugariu, Ioan Florin
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- beam equation, null-controllability, structural damping, moment problem, and biorthogonals
- Language:
- English
- Description:
- This paper is devoted to studying the effects of a vanishing structural damping on the controllability properties of the one dimensional linear beam equation. The vanishing term depends on a small parameter $\varepsilon \in (0,1)$. We study the boundary controllability properties of this perturbed equation and the behavior of its boundary controls $v_{\varepsilon }$ as $\varepsilon $ goes to zero. It is shown that for any time $T$ sufficiently large but independent of $\varepsilon $ and for each initial data in a suitable space there exists a uniformly bounded family of controls $(v_\varepsilon )_\varepsilon $ in $L^2(0, T)$ acting on the extremity $x = \pi $. Any weak limit of this family is a control for the beam equation. This analysis is based on Fourier expansion and explicit construction and evaluation of biorthogonal sequences. This method allows us to measure the magnitude of the control needed for each eigenfrequency and to show their uniform boundedness when the structural damping tends to zero.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
39706. Uniform convergence of double trigonometric series
- Creator:
- Kórus, Péter
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- sine series, cosine series, double sine series, sine-cosine series, double cosine series, uniform convergence, regular convergence, general monotone sequence, general monotone double sequence, and supremum bounded variation
- Language:
- English
- Description:
- It is a classical problem in Fourier analysis to give conditions for a single sine or cosine series to be uniformly convergent. Several authors gave conditions for this problem supposing that the coefficients are monotone, non-negative or more recently, general monotone. There are also results for the regular convergence of double sine series to be uniform in case the coefficients are monotone or general monotone double sequences. In this paper we give new sufficient conditions for the uniformity of the regular convergence of sine-cosine and double cosine series, which are necessary as well in case the coefficients are non-negative. The new results also bring necessary and sufficient conditions for the uniform regular convergence of double trigonometric series in complex form.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
39707. Uniform convergence of the generalized Bieberbach polynomials in regions with zero angles
- Creator:
- Abdullayev, F. G.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- conformal mapping, Quasiconformal curve, Bieberbach polynomials, and complex approximation
- Language:
- English
- Description:
- Let $C$ be the extended complex plane; $G\subset C$ a finite Jordan with $ 0\in G$; $w=\varphi (z)$ the conformal mapping of $G$ onto the disk $ B\left( {0;\rho _{0}}\right):={\left\rbrace {w\:{\left| {w}\right| }<\rho _{0}} \right\lbrace }$ normalized by $\varphi (0)=0$ and ${\varphi }^{\prime }(0)=1$. Let us set $\varphi _{p}(z):=\int _{0}^{z}{{\left[ {{\varphi } ^{\prime }(\zeta )}\right] }^{{2}/{p}}}\mathrm{d}\zeta $, and let $\pi _{n,p}(z)$ be the generalized Bieberbach polynomial of degree $n$ for the pair $(G,0)$, which minimizes the integral $ \iint \limits _{G}{{\left| {{\varphi }_{p}^{\prime }(z)-{P}_{n}^{\prime }(z)}\right| }}^{p}\mathrm{d}\sigma _{z}$ in the class of all polynomials of degree not exceeding $\le n$ with $P_{n}(0)=0$, ${P}_{n}^{\prime }(0)=1$. In this paper we study the uniform convergence of the generalized Bieberbach polynomials $\pi _{n,p}(z)$ to $\varphi _{p}(z)$ on $\overline{G}$ with interior and exterior zero angles and determine its dependence on the properties of boundary arcs and the degree of their tangency.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
39708. Uniform decay for a hyperbolic system with differential inclusion and nonlinear memory source term on the boundary
- Creator:
- Park, Jong Yeoul and Park, Sun Hye
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- existence of solution, differential inclusion, memory source term, and uniform decay
- Language:
- English
- Description:
- We prove the existence and uniform decay rates of global solutions for a hyperbolic system with a discontinuous and nonlinear multi-valued term and a nonlinear memory source term on the boundary.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
39709. Uniform exponential ergodicity of stochastic dissipative systems
- Creator:
- Goldys, Benjamin and Maslowski, Bohdan
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- dissipative system, compact semigroup, exponential ergodicity, and spectral gap
- Language:
- English
- Description:
- We study ergodic properties of stochastic dissipative systems with additive noise. We show that the system is uniformly exponentially ergodic provided the growth of nonlinearity at infinity is faster than linear. The abstract result is applied to the stochastic reaction diffusion equation in $\mathbb{R}^d$ with $d\le 3$.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
39710. Uniformita, či rozmanitost pohřebního ritu? Interpretace výsledků fosfátové půdní analýzy na pohřebišti únětické kultury v Praze 9 - Miškovicích
- Creator:
- Ernée, Michal and Majer, Antonín
- Type:
- article and TEXT
- Subject:
- starší doba bronzová, únětická kultura, hroby, fosfátová půdní analýza, Čechy, Early Bronze Age, Únětice culture, graves, phosphat soil analysis, and Bohemia
- Language:
- Czech and German
- Description:
- Na pohřebišti ze starší doby bronzové v Praze 9 – Miškovicích byla fosfátová analýza úspěšně použita jako doplněk archeologických a antropologických pozorování. S její pomocí se kromě „regulérních“ pohřbů s kompletně dochovanými kostrami v anatomické poloze podařilo prokázat některé doposud neznámé formy pohřbívání (ca 45 % ze všech odkrytých hrobů): A) Pohřbívání samotných kostí (někdy ve schránkách z organického materiálu) bez měkkých tkání, často s milodary, charakterizované kompletně nebo fragmentárně dochovanými kosterními pozůstatky rozptýlenými či uspořádanými na dně hrobové jámy, bez fosfátové anomálie. B) Tzv. kenotafy, prázdné jámy ležící mezi ostatními hroby, které se svým tvarem neliší od hrobových jam s pohřby, neobsahují však žádné kosterní pozůstatky ani předměty a nevykazují fosfátovou anomálii. U jednoho kenotafu byl zjištěn kamenný zával. C) „Hrobové“ jámy bez kosterních pozůstatků a bez nálezů, ale s výraznou fosfátovou anomálií respektující svým tvarem i velikostí půdorys jámy. and Burial rites: uniform or diverse? Interpretation of the results of phosphate soil analysis at the Únětice culture burial site in Prague 9 – Miškovice. Phosphate soil analysis was successfully used as a supplement to archaeological and anthropological observations at the Early Bronze Age burial site in Prague 9 – Miškovice. In addition to „regular“ burials with complete preserved skeletons resting in an anatomical position, the soil analysis was used to document heretofore unknown forms of burial (approximately 45 % of all uncovered graves): A) The burial of separate bones (in some cases in caskets made from organic material) without soft tissue, often with gifts and characterized by complete or fragmentary skeletal remains spread out or arranged in the bottom of the grave pit, without a phosphate anomaly. B) So-called „cenotaph“ (empty) graves situated between other graves. The shapes of cenotaph graves do not differ from other graves, but do not contain any bones or other objects. The cenotaph graves do not have a phosphate anomaly, but one of them has a stone packing. C) „Grave“ pits with neither skeletal remains nor finds, but with a distinct phosphate anomaly respecting the shape and even the size of the grave.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/