Search results for " math"
showing 10 items of 11183 documents
Abstracts from the CECAM workshop on computer simulations of cellular automata
1989
On the Coefficients of Multiple Series with Respect to Vilenkin System
2017
Abstract We give a sufficient condition for coefficients of double series Σ Σ n,m an,m χ n,m with respect to Vilenkin system to be convergent to zero when n + m → ∞. This result can be applied to the problem of recovering coefficients of a Vilenkin series from its sum.
Inverse estimation of model parameters for newborn brain cooling process simulations
2019
In this work, a three-dimensional simplified computational model was built to simulate the passive thermo-physiological response of part of a newborn’s head for neonate’s selective brain cooling. Both metabolicheat generation and blood perfusion were considered. The set of model parameters was selected anda sensitivity study was carried out. Analysis of dimensionless sensitivity coefficients showed that the mostimportant are: the contact thermal resistance between the cool-cap and skin, the thermal resistance ofthe plastic wall material, and deep (arterial) blood temperature. The function specification method wasapplied to estimate the value of the contact resistance. Two, four and six comp…
Voronovskaya type results and operators fixing two functions
2021
The present paper deals with positive linear operators which fix two functions. The transfer of a given sequence (Ln) of positive linear operators to a new sequence (Kn) is investigated. A general procedure to construct sequences of positive linear operators fixing two functions which form an Extended Complete Chebyshev system is described. The Voronovskaya type formula corresponding to the new sequence which is strongly influenced by the nature of the fixed functions is obtained. In the last section our results are compared with other results existing in literature.
Inverse problems for $p$-Laplace type equations under monotonicity assumptions
2016
We consider inverse problems for $p$-Laplace type equations under monotonicity assumptions. In two dimensions, we show that any two conductivities satisfying $\sigma_1 \geq \sigma_2$ and having the same nonlinear Dirichlet-to-Neumann map must be identical. The proof is based on a monotonicity inequality and the unique continuation principle for $p$-Laplace type equations. In higher dimensions, where unique continuation is not known, we obtain a similar result for conductivities close to constant.
Аппроксимации по мере: задача Дирихле, универсальность и гипотеза Римана
2021
Аппроксимации по мере используются для решения асимптотической задачи Дирихле на произвольных открытых множествах, а также для демонстрации того обстоятельства, что многие функции, в том числе дзета-функция Римана, универсальны в смысле сходимости по мере. Выдвигается предположение о связи этих результатов с гипотезой Римана. Библиография: 12 наименований.
Anwendung der elliptischen Funktionen auf Probleme der Elektrostatik
1949
Vorausgesetzt wird im folgenden eine Verteilung des elektrostatischen Feldes, die von einer der drei rechtwinkligen Koordinaten x, y, z, beispielsweise von z unabhangig ist. Das heist alle vorhandenen Leiter sind unendlich lange Zylinder beliebigen Querschnitts, deren Mantellinien parallel der z-Achse gerichtet sind. Es genugt daher den Feldverlauf in der xy-Ebene zu untersuchen. Unter dieser Voraussetzung lautet die Differentialgleichung fur das elektrostatische Potential φ =φ (x, y) XXX
Elliptische Integrale, Thetafunktionen und elliptische Funktionen
1948
Es bedeute W die Quadratwurzel aus einem Polynom dritten oder vierten Grades in einer Veranderlichen z mit lauter verschiedenen Nullstellen, und R (z, W) eine rationale Funktion von z und W. Das unbestimmte Integral von R als Funktion von z heist dann ein elliptisches Integial, falls es sich nicht auf elementare Funktionen reduzieren last.
Efficient generation of restricted growth words
2013
A length n restricted growth word is a word w=w"1w"2...w"n over the set of integers where w"1=0 and each w"i, i>1, lies between 0 and the value of a word statistics of the prefix w"1w"2...w"i"-"1 of w, plus one. Restricted growth words simultaneously generalize combinatorial objects as restricted growth functions, staircase words and ascent or binary sequences. Here we give a generic generating algorithm for restricted growth words. It produces a Gray code and runs in constant average time provided that the corresponding statistics has some local properties.
p −1-Linear Maps in Algebra and Geometry
2012
At least since Habousch’s proof of Kempf’s vanishing theorem, Frobenius splitting techniques have played a crucial role in geometric representation theory and algebraic geometry over a field of positive characteristic. In this article we survey some recent developments which grew out of the confluence of Frobenius splitting techniques and tight closure theory and which provide a framework for higher dimension geometry in positive characteristic. We focus on local properties, i.e. singularities, test ideals, and local cohomology on the one hand and global geometric applicatioms to vanishing theorems and lifting of sections on the other.