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Name Institution Title Abstract
Radulescu Ioana
USAMV Bucuresti
Chen invariants for Sasakian manifolds
Chen introduced a series of Riemannian invariants on Kaehler manifolds proved invariants for Kaehler submanifolds in complex space forms.
Simian Dana, Simian Corina University Lucian Blaga of Sibiu,
University of Chicago,
Characterization of a flexible Cubic Bezier Interpolation Scheme The aim of the paper is to introduce a cubic interpolation scheme using B´ezier curves which shape is controlled using two parameters. We make a geometric characterization of the interpolation curves and compare the results with the geometric characterization made by Stone and DeRose. Computation and graphic representations are made using MATLAB
Sprintu Iuliana Military Technical Academy New Mathematical Model for Composite thin Plates with Different Boundery Conditions In the context of composite materials technology increasingly present in the industry, this article covers a topic of great interest with theoretical and practical importance. Given the complex design of fiber-reinforced materials and their heterogeneous nature, mathematical modeling of the mechanical response under different external stress is very difficult to address in the absence of simplifying assumptions. In most structural applications, composite structures can be idealized as beams, plates or shells. The analysis is reduced from three-dimensional elasticity problem to a one-dimensional, or two-dimensional problem, based on certain simplifying assumptions that can be made because the structure is thin. This paper aims to validate a mathematical model illustrating how thin rectangular orthotropic plates respond to the actual load. Thus, from the theory of thin plates, new analytical solutions are proposed corresponding orthotropic rectangular plates having different boundary conditions. Proposed analytical solutions are considered both for solving equation orthotropic rectangular plates and for modal analysis.
Mishra Vishnu Narayan Sardar Vallabhbhai National Institute of Technology, Surat - (Gujarat), India Some approximation properties of Baskakov-Szasz-Stancu operators In this present paper, we estimate moments for these operators and obtain the recurrence relation for moments. Also, we study direct theorem, Voronovskaja type asymptotic formula for these operators and weighted approximation properties for these operators.
Cristea Valentin Gabriel Polytechnica University of Bucharest The volume of the unit n-dimensional ball. A review. The aim of this survey is to present recent research on the problem of estimating the volume of the unit n-dimensional ball. Some results from the theory of approximating the gamma function are used. Finally, some inequalities on the area of the unit n-dimensional ball are given.
Dumitrescu Sorinel Polytechnica University of Bucharest Ramanujan type formulas for approximating the gamma function. A survey. In this survey we discuss Ramanujan formula and related formulas for approximating the gamma function as many improvemements were presented in the recent past. In the final part some new inequalities are presented.
Baboş Alina Land Forces Academy "Nicolae Bălcescu" Sibiu Interpolation operators on a triangle with one curved side We construct Hermite and Birkhoff-type operators, which interpolate a given function and some of its derivatives on some interior lines of a triangle with one curved side. We consider the case when the interior line is a median. We also consider some of their product and Boolean sum operators. We study the interpolation properties and the degree of exactness of the constructed operators.
Mortici Cristinel Valahia University of Targoviste The Hyers-Ulam stability of a functional equation with bounded solutions It is the scope of this work to prove that some functional equation is Hyers-Ulam stable. Our results incorporate as a particular case a recent result of S.-M. Jung stated in [Functional equation f(x)=pf(x-1)-qf(x-2) and its Hyers-Ulam stability, J. Inequal. Appl., Volume 2009, Article ID 181678, 10 pages].
Dadarlat Marius Purdue University, West Lafayette, IN, USA Finite dimensional approximations of linear operators Quasidiagonality is an important finite dimensional approximation property of linear operators and operator algebras. Voiculescu has discovered that quasidiagonality of operator algebras is a homotopy invariant. We plan to give a quick introduction to the subject and discuss a number of basic results and open problems. If time allows, we will outline some fascinating connections with algebraic topology and noncommutative geometry.
Muraru Carmen Violeta,
Acu Ana Maria
"Vasile Alecsandri" University of Bacau, "Lucian Blaga" University of Sibiu Approximation properties of bivariate extension of q-Schurer-Kantorovich operator In this paper, we introduce a bivariate generalization of the Schurer –Kantorovich operators based on q−integers and get a Bohmann-Korovkin type approximation theorem of these operators. We also estimate the rate of convergence of the proposed operators, in the terms of first modulus of smoothness.
Rafiq Arif,
Ana Maria Acu,
Daniel Florin Sofonea
Lahore Leads University, Lahore, Pakistan,
"Lucian Blaga" University of Sibiu
Error bounds for a class of quadrature formulas A class of optimal quadrature formulas in sense of minimal error bounds are obtained. The estimations of remainder term will be given in terms of variety of norms, from an inequality point of view. Some improvements and generalizations of some results from literature will be considered.
Gavrea Bogdan Technical University of Cluj-Napoca A Newton-Monte Carlo method for solving scalar equation We present a simple modification of the Newthon-Raphson method for solving nonlinear scalar equations. The method can be used in a Monte-Carlo type setting which results in convergence for cases where the "standard" Newton method does not converge.
Nicusor Minculete,
Petrica Dicu,
Augusta Ratiu
University Transilvania from Brasov,
Lucian Blaga University of Sibiu,
Babes-Bolyai University, Cluj-Napoca,
Two reverse inequalities of Bullen's inequality and several applications In this article we present two reverse inequalities of Bullen's inequality and several applications about the arithmetic mean and the logarithmic mean.
Aral Ali,
Rașa Ioan,
Kirikkale University Turkey, Technical University of Cluj-Napoca, Kirikkale University Turkey, On The Generalized Bernstein-Durrmeyer Operators In the present paper we introduce new Bernstein-Durrmeyer type operators based on a function τ which has derivatives of all orders on [0,1], such that τ(0)=0, τ(1)=1 and τ'(x)>0 for x in [0,1]. Depending on the selection of τ, the rate of convergence of the new operators can be better than that of the classical Bernstein-Durrmeyer operators. We present an asymptotic formula and quantitative results concerning the convergence. Later we give comparisons with classical Bernstein-Durrmeyer operators. We obtain some direct results for the new operators in terms of the Ditzian-Totik modulus of smoothness. Finally a graphical example is presented.
Bascanbaz-Tunca Gulen Ankara University, Turkey A generalization of Post-Widder operators based on q-Integers In this talk, a q-generalization of the classical Post-Widder operators is introduced. The Voronovskaja-type approximation result and rate of the convergence is obtained. Approximation property of the q-Post-Widder operators in a weighted space is given and the rate of convergence is measured by means of the weighted modulus of continuity.
Pop Emilia Loredana Liceul Teologic Adventist "Maranatha" Cluj-Napoca Connections between vector optimization problems, their solutions and saddle points Considering a vector optimization problem, we attach to it the first order approximated vector optimization problem. We study the connections between the efficient solutions and saddle points of these two problems.
Acar Ozlem,
Altun Ishak
Kirikkale University, Kirikkale University Fixed Point Theorems for Weak Contractions In this talk, we present some fixed point results in partial metric space by new concepts which are the notion of (δ, L) weak contraction and (ϕ, L) weak contraction in the sense of Berinde.
Gavrea Ioan,
Ivan Mircea
Technical University of Cluj-Napoca Some inequalities on Legendre Polynomials We obtain some inequalities involving Legendre polynomials in connection with the sum of the squared Bernstein basis polynomials.
Aurelia Florea Universitatea din Craiova Some extensions of Fink’s inequality We establish some new inequalities of Fink type, in terms of the Steffensen-Popoviciu measure. We refer to a special class of convex-concave symmetric functions. By using the convexity on the co-ordinates, we extend our results from the one-dimensional case to the multidimensional case.
Tuncer Acar,
Ali Aral
Kirikkale University Turkey,
Kirikkale University Turkey,
A New Type Bernstein-Durrmeyer Operators The present paper deals with a new type of Bernstein-Durrmeyer operators on mobile interval. First, we represent the operators in terms of hypergeometric series. We also establish local and global approximation results for these operators in terms of modulus of continuity. We obtain an asymptotic formula for these operators and in the last section we present better error estimation for the operators using King type approach.
Antonio-Jesus Lopez-Moreno and Jose-Manuel Latorre-Palacios University of Jaen, Spain. Asymptotic properties of multivariate Durrmeyer type operators We present some extensions of preceding results of the authors that can be used to study the asymptotic behavior and localization properties for several Durrmeyer type operators in both the univariate and the multivariate case.
Paltanea Radu Transilvania University of Brasov Approximation of fractional derivatives We study the approximation of fractional derivatives, in diverse senses by means of positive linear operators. Quantitative aspects are also considered.
Marius Birou Tehnical University Cluj-Napoca, Romania About a linear positive operator which preserves test functions $e_0$ and $e_2$ In this paper we present an operator which preserves the test functions $e_0$ and $e^2$. We compare this operator with the classical Durrmeyer operator.
Adrian Girjoaba Lucian Blaga University of Sibiu, Romania Bernstein's theorem on minimal surfaces, a computer aided proof. The Bernstein's famous theorem on minimal surfaces is "proved" using MAPLE. Besides the interesting, in themselves", facts revealed by this soft, there is, again, opened the challenging debate about what is to be accepted or not, and how much, from the aide that computers are (more and more) able to give us in our study of abstract, fundamental, (not only) mathematical, phenomena.
Agratini Octavian Babes - Bolyai University, Cluj - Napoca Linear approximation processes of integral type We present classes of linear positive operators of integral type. Approximation properties are explored such as the rate of convergence, uniform approximation over unbounded intervals, convergence in some weighted spaces, statistical convergence. Special cases are highlighted.
Heiner Gonska University of Duisburg-Essen Grüss-Voronovskaya Estimates for Bernstein-type Operators We will present a combination of Voronovskaya- and Grüss-type results for certain Bernstein-type operators. These will be inequalities which cover all the operators on the "Păltănea scale" between the genuine Bernstein-Durrmeyer and the classical Bernstein operators. We will also briefly discuss the complex case. The talk is based on joint work with Sorin Gal.
Daniela Inoan,
Ioan Rasa
Technical University of Cluj-Napoca A de Casteljau type algorithm in matrix form We describe a de Casteljau type algorithm in matrix form for some linear operators that appear in Approximation Theory. Some monotonicity preserving properties of the operators are proved by using this algorithm.
Stan Gabriel Transilvania University, Brasov A Voronovskaya-type Result for a Generalized Baskakov- Durmeyer Operator In this article we give a generalization of the Baskakov- Durmeyer operator using Kantorovich method and we prove convergence properties and a Voronovskaj- type theorem for these new operators.
Margareta Heilmann University of Wuppertal, Germany k-th order Kantorovich type modification of the operators Un We study the k-th order Kantorovich type modi cation of the operators Un introduced and investigated by H. Gonska and R. Paltanea. The op- erators constitute a link between the classical Bernstein operators and the genuine Bernstein-Durrmeyer operators. We will present explicit formulas and recurrence relations for the images of monomials and for moments of arbritary order. The talk is based on joint work with Ioan Rasa.
Ioan Tincu Lucian Blaga University of Sibiu, Romania Characterization theorems of Jacobi and Laguerre polynomials In this paper we prove a property of the Jacobi polynomials and the Laguerre polynomials.
Emil C Popa Lucian Blaga University of Sibiu, Romania Some inequalities for the Landau constants Starting with some inequalities for the Wallis ratio and the Ramanujan type formulas for the Landau constants, we obtain new estimates for this constants.
Maria Daniela Rusu
Elena DORINA Stanila
University of Duisburg-Essen Chebyshev-Grüss-Type Inequalities for the Bernstein-Euler-Jacobi Operators The classical form of Grüss’ inequality gives an estimate of the difference between the integral of the product and the product of the integrals of two functions in C[a, b]. The aim of this talk is to present some Chebyshev-Grüss-type inequalities and apply them to the Bernstein-Euler-Jacobi (BEJ) operators of first and second kind. The first and second moments of the operators will be of great interest.
Eugen Constantinescu, Adrian Branga Lucian Blaga University of Sibiu, Romania Remarks on a class of quadrature formulas In this paper we propose to find a class of quadrature formulas with higher degree of exactness and moreover possess a Peano kernel that does not change the sign. We present a new method that allows us to study the remainder operator based on the properties of a set of linear and positive functionals.
Heiner Gonska University of Duisburg-Essen Academician Prof. Dr. D.D. Stancu (1927 - 2014): His Influence on my Mathematical Work An (incomplete) survey will be given on how Prof. Stancu's publications influenced the speaker's work. Some keywords: approximation by pseudopolynomials, Hermite-Fejér interpolation, simultaneous approximation, Schoenberg splines, algorithms of de Casteljau-type.
Voichita Adriana Radu Babes-Bolyai University, Cluj Napoca Academician Professor D.D. Stancu : a life time dedicated to the numerical analysis and theory of approximation This spring, on April 17, the mathematical community suffered a big loss: the decease of Academician Professor D.D. Stancu, a Romanian distinguish mathematician. He was an Emeritus member of American Mathematical Society and an Honorary member of the Romanian Academy. He was also a member of the German society “Gesellschaft fur Angewandte Mathematik und Mechanik”. His publication list about 160 items (papers and books) and more than 60 papers containing his name in their titles. The main contributions of research work of Professor D.D. Stancu fall into the following list of topics:  Approximation of functions by means of linear and positive operators, Representation of remainders in linear approximation procedures, Probabilistic methods for construction and investigation of linear positive operators,  Interpolation theory, Spline approximation, Numerical differentiation, Orthogonal polynomials, Numerical quadratures and cubatures, Taylor-type expansions, use of Interpolation and Calculus of finite differences in Probability theory and Mathematical statistics.
Andrei Vernescu Valahia University of Targoviste Acad. Prof. D. D. Stancu, a respectful remember and a deep homage The presentation consists in a remembering of the life and of the work of our beloved master Acad. Prof. D.D. Stancu.