bluuebunny/crossref_metadata_2025 huggingface dataset:
Analysis of the dynamic relationship between income and expenditure of the Moscow budget (2013:01÷2023:03): Time-frequency approach
Authors: Karaev A. , Ponkratov V. , Gueva L.
Published: October 2023

The article conducts a study of the sustainability of the Moscow city budget, based on an analysis of the time-frequency relationship between its monthly expenses and income, for the period from December 2012 to March 2023, using the calculated values of wavelet coherence and the phase difference between the wavelets of expenses and income. Four main concepts concerning the correlation between government expenditures and income, including tax revenues, are considered — these are the hypotheses: “income-expenses”; “expenses-income”; fiscal synchronization and the institutional separation hypothesis. The results of the study show that in the case of the Moscow city budget, all four dynamic relationships between its income and expenses are observed, in different time periods, on different time scales, over the observation time interval (2013:01?2023:03), proposed by the theory. Assessing the dynamic relationship between income and expenditure of the budgets of the constituent entities of the Russian Federation is important for the development of fiscal policy aimed at increasing the sustainability of the budgets of the constituent entities of the Russian Federation.
Development of the social component as a guarantee of sustainable economic development of the organization
Authors: Trofimov O. , Kazakova T.
Published: October 2023

The uncertainty of the external environment significantly increases the risks of sustainable development of economic entities, pushes them to innovate. Among the variety of turbulence factors, the authors propose to focus on three drivers that are most significant in their impact: digitalization, geopolitics, ecology. The purpose of the study is to describe a transformational approach to the social component, the effectiveness of which is assessed by indicators of financial stability of an economic entity. The tasks of determining the key competencies of successful companies are solved, the main organizational components of the social component are substantiated, the use of the technology of implementing the proposed concept is demonstrated on the example of IT companies. The authors used general scientific methods of generalization, deduction, abstraction, theoretical approach of ascent from the abstract to the concrete; experimental methods of observation, modeling and comparison. According to the results of the approbation, it is proved that the development of the social component is the key to stable economic development of an economic entity.
Technological sovereignty as an imperative of national industrial policy
Authors: Vinslav Yu.
Published: October 2023

The strategically significant task of achieving technological sovereignty is considered in relation to the general state of Russian industry. The main industrial trends of recent years are characterized. The ways of improving the domestic practice of state regulation of industry are formulated. Including: fuller use of the best world practice of industrial policy (China, USA, South Korea, Japan, India); adjustment of domestic legislation on this issue; improvement of the system of strategic planning of industrial development. The national Industrial Policy is considered as a strategic course of the state for the sustainable functioning and progressive development of the industrial sphere, meeting the national interests and national security of the country. The content of objects and subjects of industrial policy, as well as the vision of the system of strategic planning of the industrial sphere with an emphasis on the needs of the domestic market are clarified. The key provisions of the Concept of Technological Development of the country until 2030, approved by the Government of Russia, are outlined. The basic principles of improving the mechanism of import substitution and the directions of its implementation at the macro level are proposed. It is recommended to concentrate import substitution efforts on industrial goods and complex technical systems that are strategically important from the point of view of national security. Pay special attention to the final types of industrial products containing difficult-to-replace (the most complex) components. To modernize the composition and interaction of technological chains of organizations producing strategic replacement products. In general, a course is needed to increase the strategic flexibility of Russian industry and accelerate the diversification of its scientific and production potential.
Directions of adjustment of national financial policies in the documents of international organizations and the possibility of their use in Russian practice
Authors: Shmigol N.
Published: October 2023

In order to achieve the national development goals of the Russian Federation until 2030 and maintain sustainable economic growth rates, considerable attention is paid to the state financial policy, its transformation taking into account global challenges and shocks. In this regard, the documents of international and intergovernmental organizations on the adjustment of national financial policies in the post-pandemic period are being analyzed as part of the search for universal tools to ensure inclusive and sustainable economic growth while unconditionally ensuring the effectiveness of public spending. The analysis allows to conclude that the scientific basis of transformation is the concept of "sustainable finance" now used in the public administration sector, strategic priorities for the development of national economies in the post-pandemic period are designed to be research and innovation, green economy and digital economy, ensuring economic and social sustainability, the revision of national financial policies will occur in accordance with these priorities. This study reveals the priority directions and tools for the transformation of national financial policies that can be taken into account in Russian practice.
An approach to forecasting macro indicators in Russia
Authors: Borisova O. , Yashchenko A.
Published: October 2023

Methods of forecasting macro indicators are studied in the work. Their diversity and groups of regressors used for prognostic purposes are shown. The influence of behavioral factors on the size of the predicted macro–indicator — GDP is substantiated. It is proved that the impact of the expectation of changes by business in the next three months and production costs on GDP. A regression model is proposed that allows us to promptly take into account business sentiment when forecasting GDP, which will allow us to more accurately predict the dynamics of its changes.
On a class of DIMSIMs methods
Authors: Coroian Iulian
Published: October 2023

Not available.
The acceleration of the convergence of certain approximant sequences of the solutions of certain equations in normed spaces
Authors: Diaconu Adrian
Published: October 2023

Not available.
Convexité au sens direct ou inverse et applications dans l'optimisation vectorielle
Authors: Popovici Nicolae
Published: October 2023

(in English) The aim of this paper is to study vector optimization poblems involving objective functions which are convex in some direct or inverse sense (i.e. a special class of cone-quasiconvex functions). In particular, it is shown that the image of the objective function is a cone-convex set, property which is important from the scalarization point of view in vector optimization.

(in French) Le but de cet article est d'etudier les problemes d'optimisation vectorielles ayant des fonctions objectifs convexes au sens direct ou inverse. Il s'agit notamment de donner des conditions suffisantes pour que l'image d'un ensemble convexe par des fonction objectifs cone-quasiconvexes soit un ensemble cone-convexe, propriete qui joue un role important dans la plupart des methodes de scalarisation utilisees dans l'optimisation vectorielle.
On the numerical evaluation of certain 2-D singular integrals
Authors: Gori Laura , Cascio Laura Lo , Santi Elisabetta
Published: October 2023

The problem of approximating certain two-dimensional Cauchy principal value integrals is here considered, product integration formulas with multiple nodes are presented and the behaviour of the remainder is analyzed. Next a particular class of cubature rules is generated, having the peculiar property that the set of the nodes holds fixed while their multiplicities vary. Some numerical examples of application of the latter rules are also provided.
Some sequences supplied by inequalities and their applications
Authors: Şoltuz Ştefan M.
Published: October 2023

In order to prove the convergence of Ishikawa and Mann iterations, the convergence of one type of sequences is needed. Our purpose, in this note, is to give a new proof of the convergence for one of them. We also give generalizations for the sequences.
An application of the fixed point theorem of Bohnenblust-Karlin to the Darboux problem for a multivalued inclusion
Authors: Teodoru Georgeta
Published: October 2023

Not available.
On the White's algorithm for fractional programming
Authors: Ţigan Ştefan
Published: October 2023

In this note we extend for fractional case a method due to White for solving a problem of maximizing over a finite set a function with some special "convexity" properties. Three algorithms applied to a transformation of the initial problem into a maximizing an auxilliary non-fractional function over a bi-product set are given.
On the flow of a viscous thin layer on an inclined plane driven by a constant surface tension gradient
Authors: Borşa Emilia , Gheorghiu Călin Ioan
Published: October 2023

Steady flow of a thin layer (trickle, rivulet) of viscous fluid down an

inclined surface is considered, via a thin-film approximation. The work extends

the study by Duffy and Moffatt [7] of gravity-driven thin trickle of viscous fluid

to include the effects of a surface tension gradient. It acts on the free surface of

the layer. At the same time the work tries an alternative analysis to our tradi-

tional approaches exposed in [6] and the papers quoted there. Asymptotic and

numerical results for several values of volume flux and surface tension gradients

are carried out.
Harmonic blending approximation
Authors: Delvos Franz-Jürgen
Published: October 2023

The concept of harmonic Hilbert space \(H_D({\mathbb R} ^n)\) was introduced in [2] as an extension of periodic Hilbert spaces [1], [2], [5], [6]. In [4] we introduced multivariate harmonic Hilbert spaces and studied approximation by exponential-type function in these spaces and derived error bounds in the uniform norm for special functions of exponential type which are defined by Fourier partial integrals \(S_b(f)\):

\[S_b(f)(x)=\int _{ {\mathbb R} ^n } \chi _{[-b,b]}(t) F(t) \exp(i(t,x)) dt,\]\([-b,b]=[-b_1,b_1]\times ... \times [-b_n ,b_n], \quadb_1>0,...,b_n>0\), where\(F(t)\sim \left( {\textstyle\frac 1{2\pi}}\right) ^n\ \int_{{\mathbbR} ^n}f(x) \exp (-i(x,t))dx \ \in L_2({\mathbb R} ^n) \capL_1({\mathbb R} ^n)\)is the Fourier transform of \(f \in L_2({\mathbb R} ^n) \capC_0({\mathbb R} ^n)\). In this paper we will investigate more general approximation operators \(S_\psi \) in harmonic Hilbert spaces of tensor product type.
Inequalities for some iterated linear operators and their applications in approximation theory
Authors: Knoop Hans-Bernd , Zhou Xinlong
Published: October 2023

Some inequalities for the ”derivatives” of iterated linear operators will be presented, which will be applied for the investigation of degrees of approximation.

Thus, with the application of the Laplacian we improve some classical results concerning the Jackson type estimate, the inverse theorem as well as the saturation phenomenon
On some Aitken-Steffensen-Halley-type methods for approximating the roots of scalar equations
Authors: Păvăloiu Ion
Published: October 2023

In this note we extend the Aitken-Steffensen method to the Halley transformation. Under some rather simple assumptions we obtain error bounds for each iteration step; moreover, the convergence order of the iterates is 3, i.e. higher than for the Aitken-Steffensen case.
Stancu Curves in CAGD
Authors: Hatvany Adalbert Csaba
Published: October 2023

Starting from the one-parameter dependent linear polynomial Stancu operator, we consider the related polynomial curve scheme with one scalar shape parameter. This scheme, called by us the Stancu curve scheme, generalizes in a suitable manner the classical Bernstein-Bézier scheme and provides more design flexibility by means of the shape parameter.
On the expansion schemes in trajectory reversing method
Authors: Măruşter Ştefan
Published: October 2023

The paper deals with certain expansion schemes in trajectory

reversing method for estimating asymptotic stability region of

nonlinear dynamical systems. The asymptotic behavior of the

sequence of estimates is investigated. Some numerical examples are

given.
Aitken-Steffensen type methods for nondifferentiable functions (I)
Authors: Păvăloiu Ion
Published: October 2023

We study the convergence of the Aitken-Steffensen method for solving a scalar equation \(f(x)=0\). Under reasonable conditions (without assuming the differentiability of \(f\)) we construct some auxilliary functions used in these iterations, which generate bilateral sequences approximating the solution of the considered equation.
Use of identity of A. Hurwitz for construction of a linear positive operator of approximation
Authors: Stancu Dimitrie D.
Published: October 2023

By using a general algebraic identity of Adolf Hurwitz [1], which generalizes an important identity of Abel, we construct a new operator \(S_m^{(\beta_1,\ldots,\beta_m)}\) approximating the functions. A special case of this is the operator \(Q_m^\beta\) of Cheney-Sharma.
We show that this new operator, applied to a function \(f\in C[0,1]\), is interpolatory at both sides of the interval \([0,1]\), and reproduces the linear functions.
We also give an integral representation of the remainder of the approximation formula of the function \(f\) by means of this operator. By applying a criterion of T. Popoviciu [2], is also given an expression of this remainder by means of divided
difference of second order.
Sequences of linear operators related to Cesàro-convergent sequences
Authors: Anisiu Mira-Cristiana , Anisiu Valeriu
Published: October 2023

Given a Cesàro-convergent sequence of real numbers\((a_{n})_{n\in \mathbb{N}}\), a sequence \((\varphi_{n})_{n\in\mathbb{N}}\) of operators is defined on the Banach space \(\mathcal{R}(I,F)\) of regular functions defined on \(I=[0,1]\) and having values in a Banach space \(F\), \[\varphi_{n}(f)=\frac{1}{n}\sum_{k=1}^{n}a_{k}f\left( \tfrac{k}{n}\right) .\]It is proved that if, in addition, the sequence \(\big( \frac{\left|a_{1}\right| +\ldots+\left| a_{n}\right| }{n}\big)_{n\in\mathbb{N}}\) is bounded, then \(\varphi_{n}(f)\) converges to \(a\cdot\int\nolimits_{0}^{1}f,\) where \(a=\lim_{n\rightarrow\infty}\frac{a_{1}+\ldots+a_{n}}{n}.\) The converse of this statement is also true. Another result is that the supplementary condition can be dropped if the operators are considered on the space \(\mathcal{C}^{1}(I,F)\).
Direct and indirect approximations to positive solution for a nonlinear reaction-diffusion problem. II. Indirect approximation
Authors: Gheorghiu Călin Ioan , Trif Damian
Published: October 2023

In this paper we continue the study initiated in our previous work [3] and design a projection-like algorithm to approximate a hyperbolic unstable "point''. This "point'' is in fact the positive solution of the reaction-diffusion problem considered in [3] and the algorithm modifies a finite difference (Euler)-finite elements scheme by incorporating the independence of the length of the domain condition. The numerical results are in good agreement with those obtained by direct methods as well as with those reported in [2], where the problem is solved in a Hamiltonian setting. At the same time we improve our previous results reported in [3].
Approximation of derivatives by nonlinear operators
Authors: Păltănea Radu
Published: October 2023

Two theorems on simultaneous approximation are obtained by using generalized convex operators.
On the convergence of a method for solving two point boundary value problems by optimal control
Authors: Scheiber Ernest
Published: October 2023

Using the idea of the least squares method, a nonlinear two point boundary value problem is transformed into an optimal control problem. For solving the optimal control problem the gradient method is used. The convergence of the method is investigated and numerical results are reported.
On stability conditions of vector \(l_\infty\)-extreme combinatorial problem with Pareto principle of optimality
Authors: Emelichev Vladimir A. , Leonovich Andrey M.
Published: October 2023

We consider the multicriteria problem of combinatorial optimization with partial criteria of the kind MINMAX MODUL. The parameters of criteria are subject to "small" independent perturbations. The class of problems for which new Pareto optima do not appear, but some trajectories may lose optimality under those perturbations, is distinguished.
On the Cauchy transform and complex cubic splines
Authors: Iancu Crăciun , Oproiu Tiberiu , Pop Alexandru , Pop Vasile
Published: October 2023

In this paper we approximate the Cauchy transform of a complex function on a simple closed curve, using an interpolation cubic spline function given by Iancu (1987).
Bases for shape preserving curves
Authors: Pitolli Francesca
Published: October 2023

The shape preserving properties of a curve in \(\mathbb{R}^2\) depend on the properties of the function basis we use in its representation. Both sign consistent and totally positive bases have shape preserving properties useful in Computer Aided Geometric Design. Some of the most useful properties are lightened and some examples of shape preserving bases are given.
On spline approximation for bivariate functions of increasing convex type
Authors: Denuit Michel , Lefèvre Claude , Mesfioui Mhamed
Published: October 2023

The motivation of the paper is to construct the largest and smallest families of functions that allow us to generate the bivariate continuous stochastic orderings of increasing convex type introduced recently in Denuit et al. (1999). The main step will consist in deriving a spline approximation for bivariate continuous increasing convex functions, which extends to the bivariate case a fundamental result obtained by Popoviciu (1941).
Solving discrete multiattribute problems under risk based on an approximation
Authors: Ríos-Insua Sixto , Mateos Alfonso , Jiménez Antonio
Published: October 2023

We consider the multiattribute decision making problem under risk with imprecise information on the decision maker's preferences, modelled by means of a vector utility function. We propose an interactive decision aid approach, which uses an idea of approximation to the utility efficient set and qualitative comparisons for the decision maker, to overcome the possible difficulty in generate it. An application to university selection illustrates the procedure.
On the convergence of iterates to fixed points of analytic operators
Authors: Argyros Ioannis K.
Published: October 2023

The results in this study deal with the question: given that an analytic operator has fixed point, when is it true that iterates (under the operator) of nearby points converge to the fixed point? We take advantage of the analyticity of the operator to show that it is possible to enlarge the convergence radius for the method of successive substitutions or Newton's method. A numerical example is finally given to show that under our conditions there exists a wider choice of initial guesses than before.
New Chebyshev type inequalities for sequences of real numbers
Authors: Dragomir S. S.
Published: October 2023

Some new inequalities of Chebyshev type for sequences of real numbers are pointed out.
Hermite bicubic spline collocation method for Poisson's equations
Authors: Puşcaş Mihaela
Published: October 2023

In this paper is presented a bicubic spline collocation method for

the numerical approximation of the solution of Dirichlet problem

for the Poisson's equation. The approximating solution is

effectively determined in a bicubic Hermite spline functions space

by using a suitable basis constructed as a tensorial product of

univariate spline spaces.
Bernstein-Schurer bivariate operators
Authors: Bărbosu Dan
Published: October 2023

The sequence of bivariate operators of Bernstein-Schurer is constructed and some approximation properties of this sequence are studied.
On a mean value theorem connected with Hermite-Hadamard's inequality
Authors: Pop Ovidiu T.
Published: October 2023

In this paper we prove a mean-value theorem for integral calculus, then we demonstrate properties of the mean point. In the end we give an extension of Hermite-Hadamard's inequality.
Biermann interpolation of Birkhoff type
Authors: Birou Marius
Published: October 2023

If \(P_{0},P_{1},...,P_{r}\) and \(Q_{0},Q_{1},...,Q_{r}\) are Birkhoff univariate projectors which form the chains\[P_{0}\le P_{1}\le\dots\le P_{r},\quad Q_{0}\le Q_{1}\le\dots\le Q_{r},\]we can define the Biermann operator of Birkhoff type\[B_{r}^{B}=P_{0}^{\prime}Q_{r}^{\prime\prime}\oplus P_{1}^{\prime}Q_{r-1}^{\prime\prime}\oplus\dots\oplus P_{r}^{\prime}Q_{0}^{\prime\prime},\]where \(P_{1}^{\prime},\dots,P_{r}^{\prime}\),\(Q_{1}^{\prime\prime},\dots ,Q_{r}^{\prime\prime}\) are the parametric extension. We give the representations of Biermann interpolant of Birkhoff type for two particular cases (Abel-Goncharov and Lidstone projectors) and we calculate the approximation order of Biermann interpolant in these cases.
Extensions of certain relations of the classical analysis
Authors: Halic Gheorghe , Halic Eduard
Published: October 2023

In this work we deal with certain integrals which are convergent for a set of values of a parameter but which become divergent for other values. We extend some relations involving such integrals, replacing them by neutralized ones.
An approximation operator of Stancu type
Authors: Toader Silvia
Published: October 2023

We study the behavior of Stancu-Goldman's operator on the second degree functions.
On the modified beta approximating operators of second kind
Authors: Miheşan Vasile
Published: October 2023

We shall define a general linear operator from which we obtain as particular case the modified beta second kind operator\[(T_{p,q}f)(x)=\frac{1}{B(p,q)}\int_0^\infty\tfrac{u^{p-1}}{(1+u)^{p+q}}f\left(\frac{B(p,q)}{B(p+a,q-a)}u^ax\right){\rm d}u.\] We consider here only the case \(a=1\). We obtain several positive linear operators as a particular case of this modified beta second kind operator.
Accelerating the convergence of the iterative methods of interpolatory type
Authors: Păvăloiu Ion
Published: October 2023

In this paper we deal with iterative methods of interpolatory type, for solving nonlinear equations in Banach spaces. We show that the convergence order of the iterations may considerably grow if the nodes are properly controlled.
Vector subdifferentials and tangent cones
Authors: Stamate Cristina
Published: October 2023

Following the Rockafellar's definition for the subdifferential of a real map we define a vector subdifferential using the normal cone to the epigraph of the function. For several kinds of normal cones we have different subdifferentials; we give properties, links between them, links with addapted directional derivatives and a genaralization for the Correa Joffré Thibault and for Zagrodny theorem from the real case.
On the boundedness of the associated sequence of Mann iteration for several operator classes with applications
Authors: Şoltuz Ştefan M.
Published: October 2023

We prove that the associated sequence of Mann iteration is decreasing and hence bounded provided that the operator satisfies minimal assumptions. In particular we obtain for a nonexpansive operator that the associated sequence of Ishikawa iteration is decreasing for a nonexpansive operator. Applications to the convergence of Mann iteration are given.
Interpolation par des fonctions entières
Authors: Groza Ghiocel , Pop Nicolae
Published: October 2023

In French.
Soit \(A\) une algèbre normè unifère commutative complète sur un corps commutatif à valeur absolue non triviale. L'article montre qu'il existe une fonction entière, ayant les coefficients en \(A\) qui donne une solution pour un problème d'interpolation infinie en \(A\).
In English.
Let \(A\) be a complete commutative uniferous norm algebra over a nontrivial absolute value commutative field. The article shows that there exists an integer function, having the coefficients in \(A\) that gives a solution for an infinite interpolation problem in \(A\).
About some mean-value theorems for B-differentiable functions
Authors: Pop Ovidiu T. , Farcaş Mircea
Published: October 2023

In this paper we shall demonstrate a general mean-value theorem for \(B\) -differentiable functions. By particularization, we obtain Pompeiu-type and Ivan-type theorems for \(B\)-differentiable functions.
Fixed points and integral inclusions
Authors: Petruşel Adrian
Published: October 2023

The aim of this paper is to present, as applications of some fixed point theorems, existence results for integral equations and inclusions.
The equivalence between the T-stabilities of modified Mann-Ishikawa and Mann-Ishikawa iterations
Authors: Şoltuz Ştefan M.
Published: October 2023

We show that all \(T\)-stabilities of Mann-Ishikawa iterations and modified Mann-Ishikawa iterations are equivalent.
A dual generalization of convex functions
Authors: Apetrii M.
Published: October 2023

As it is well known, the convexity property of a function may be described by the quasiconvexity property of all "the dual perturbations" of this function. If we consider the "dual perturbation" only in a subset \(M\subset X^{\ast}\) we obtain a general class of functions called \(M\)-convex. In this paper we establish some special properties and a continuity theorem of this new type of functions.
Approximation and geometric properties of some complex Bernstein-Stancu polynomials in compact disks
Authors: Gal Sorin G.
Published: October 2023

In this paper, the order of simultaneous approximation, convergence results of the iterates and shape preserving properties, for complex Bernstein-Stancu polynomials (depending on one parameter) attached to analytic functions on compact disks are obtained.
Unsteady boundary layer flow and heat transfer over a stretching sheet: heat flux case
Authors: Revnic Cornelia , Groşan Teodor , Pop Ioan
Published: October 2023

Unsteady two-dimensional boundary layer flow and heat transfer over a stretching flat plate in a viscous and incompressible fluid of uniform ambient temperature is investigated in this paper. It is assumed that the velocity of the stretching sheet and the heat flux from the surface of the plate vary inverse proportionally with time. Two equal and opposite forces are impulsively applied along the plate so that the plate is stretched keeping the origin fixed. Using appropriate similarity variables, the basic partial differential equations are transformed into a set of two ordinary differential equations. These equations are solved numerically for some values of the governing parameters using the Runge-Kutta method of fourth order. Flow and heat transfer characteristics are determined and represented in some tables and figures. It is found that the structure of the boundary layer depends on the ratio of the velocity of the potential flow near the stagnation point to that of the velocity of the stretching surface. In addition, it is shown that the heat transfer from the plate increases when the Prandtl number increases. The present results include also the steady situation as a special case considered by other authors. Comparison with known results is very good.
Numerical experiments with two smoothing type-algorithms for nonlinear complementarity problems
Authors: Achache M. , Boudiaf N. , Keraghel A.
Published: October 2023

In this paper we deal with the numerical experiments of two smoothing descent-type algorithms for solving nonlinear complementarity problems (NCP). The first algorithm is due to Kanzow and the second one is due to Peng. These algorithms are both based on the reformulation of (NCP) as unconstrained minimization problems by using some smoothing merit functions including the so-called (NCP)-functions. Under suitable conditions they both showed that any stationary point of these problems are solutions of (NCP). For their numerical performances many strategies are used. Finally, these algorithms are applied to some problems of (NCP) found in the literature.
Some cone separation results and applications
Authors: Durea M.
Published: October 2023

In this note we present some cone separation results in infinite dimensional spaces. Our approach is mainly based on two different types of cone outer approximation. Then we consider an application to vector optimization.
General convergence of the methods from Chebyshev-Halley family
Authors: Pomian Raluca Anamaria
Published: October 2023

In this paper we study the Chebyshev-Halley family (which contains, as particular cases, the Chebyshev method, Halley method, super-Halley method and the C-method). For Chebyshev and super-Halley methods we give a global theorem of convergence. In the end of the paper we study the basins of attraction of the roots of a polynomial with real coefficients. They are obtained when we apply to that polynomial the methods from the Chebyshev-Halley family methods.
The equivalence between T-stabilities of Krasnoselskij and Ishikawa iterations
Authors: Şoltuz Ştefan M.
Published: October 2023

We prove the equivalence between the \(T\)-stabilities of Krasnoselskij and Ishikawa iterations; a consequence is the equivalence with the \(T\)-stability of Picard-Banach iteration.
Extending Broyden's method to interaction problems
Authors: Haelterman Robby , Degroote Joris , Vierendeels Jan , Van heule Dirk
Published: October 2023

The solution of problems involving the interaction of different systems is a domain of ongoing research, although often a good solver already exists for each system separately. In this paper we draw our ideas from one of the best known all-round quasi-Newton methods: Broyden's rank-one update, which we extend to algorithms using 2 approximate Jacobians. A comparison is made with the iterative substructuring method and Aitken's acceleration method. It is shown that a Broyden method using only a single approximate Jacobian performs best.
Effect of the magnetic field and heat generation on the free convection flow in a tall cavity filled with a porous medium
Authors: Revnic Cornelia , Groşan Teodor , Pop Ioan
Published: October 2023

An analytical study of the steady magnetohydrodynamics (MHD) free convection in an tall cavity filled with a fluid-saturated porous medium and with internal heat generation has been performed. It is considered that the Darcy law model is used. It is assumed that a uniform magnetic field normal to the walls of the cavity is externally imposed. The values of the governing parameters are as follows: Hartmann number \(\operatorname{Ha}=0, 10\) and \(50\), Rayleigh number \(\operatorname{Ra} = 10^{3}\), and the aspect ratio \(a=0.01\). The velocity and temperature profile are determined. These profiles are presented graphically at the center line of the cavity. It is found that the analytical solution is in very good agreement with the numerical solution which is obtained by solving partial differential equations using a finite-difference method.
Finding good starting points for solving equations by Newton's method
Authors: Argyros Ioannis K.
Published: October 2023

We study the problem of finding good starting points for the semilocal convergence of Newton's method to a locally unique solution of an operator equation in a Banach space setting. Using a weakened version of the Newton-Kantorovich theorem we show that the procedure suggested by Kung [6] is improved in the sense that the number of Newton-steps required to compute a good starting point can be significantly reduced (under the same computational cost required in the Newton--Kantorovich theorem [3], [5]).
Some types of convex functions on networks
Authors: Marian Daniela
Published: October 2023

We present and study some kinds of convex functions defined on undirected networks. The relations between these concepts are also presented. We adopt the definition of network as metric space used by Dearing P. M. and Francis R. L. in 1974.
On the convergence of Steffensen-type methods using recurrent functions nonexpansive mappings
Authors: Argyros Ioannis K. , Hilout Saïd
Published: October 2023

We introduce the new idea of recurrent functions to provide a new semilocal convergence analysis for Steffensen-type methods (STM) in a Banach space setting. It turns out that our sufficient convergence conditions are weaker, and the error bounds are tighter than in earlier studies in many interesting cases[1]-[5], [12], [14]-[17], [23], [24], [26]. Applications and numerical examples, involving a nonlinear integral equation of Chandrasekhar-type, and a differential equation are also provided in this study.
Korovkin-type convergence results for multivariate Shepard formulae
Authors: Nowak Oliver
Published: October 2023

We present a new convergence proof for classic multivariate Shepard formulae within the context of Korovkin-type convergence results for positive operators on spaces of continuous real valued functions.
Continuity of the quenching time in a semilinear heat equation with Neumann boundary condition
Authors: N'gohisse Firmin K. , Boni Théodore K.
Published: October 2023

This paper concerns the study of a semilinear parabolic equation subject to Neumann boundary conditions and positive initial datum. Under some assumptions, we show that the solution of the above problem quenches in a finite time and estimate its quenching time. We also prove the continuity of the quenching time as a function of the initial datum. Finally, we give some numerical results to illustrate our analysis.
The convergence of the Euler's method
Authors: Sălăjan (Pomian) Raluca Anamaria
Published: October 2023

In this article we study the Euler's iterative method. For this method we give a global theorem of convergence. In the last section of the paper we give a numerical example which illustrates the result exposed in this work.
Local convergence of Newton's method using Kantorovich convex majorants
Authors: Argyros Ioannis K.
Published: October 2023

We are concerned with the problem of approximating a solution of an operator equation using Newton's method. Recently in the elegant work by Ferreira and Svaiter [6] a semilocal convergence analysis was provided which makes clear the relationship of the majorant function with the operator involved. However these results cannot provide information about the local convergence of Newton's method in their present form. Here we have rectified this problem by using two flexible majorant functions. The radius of convergence is also found. Finally, under the same computational cost, we show that our radius of convergence is larger, and the error estimates on the distances involved is finer than the corresponding ones [1], [11]-[13].
Durrmeyer-Stancu type operators
Authors: Pop Ovidiu T. , Bărbosu Dan
Published: October 2023

Considering two given real parameters \(\alpha, \beta\) satisfying the conditions \(0\leq\alpha\leq\beta\), D. D. Stancu [7] constructed and studied the linear positive operators \(P^{(\alpha,\beta)}_m:C([0,1])\to C([0,1])\), defined for any \(f\in C([0,1])\) and any positive integer \(m\) by (1). In this paper we are dealing with the Durrmeyer form of Stancu's operators. Some approximation properties of these Durrmeyer-Stancu operators are established. As a particular case, we retrieve approximation properties for the classical Durrmeyer operators [5].
The first absolute moment for some operators
Authors: Pop Ovidiu T. , Braica Petru I.
Published: October 2023

In this paper we will determinate the first absolute moments for Bernstein, Szász-Mirakjan, Bleimann-Butzer-Hahn, Meyer-König and Zeller operators. For the Szász-Mirakjan operators we give some properties with the absolute moment of high order.
Le château de Pocé en Anjou (Distré, Maine-et-Loire), vers 1200-vers 1400
Authors: Gaugain Lucie
Published: October 2023

Les parties subsistantes du château de Pocé à Distré, dans le Saumurois, ne conservent pas moins de huit phases principales de construction. Deux d’entre elles peuvent être attribuées à des hommes de guerre qui firent carrière dans le sillage de grandes figures politiques. La première campagne (vers 1200), attribuable à Olivier de Daon, fidèle du sénéchal d’Anjou Guillaume des Roches, concerne une grande tour couverte d’une étonnante voûte à l’angevine ayant en partie conservé son décor peint de fleurettes. La dernière campagne (vers 1390), attribuable à Pierre de la Rocherousse, proche du connétable Bertrand Du Guesclin, magnifie l’entrée de la place en intégrant la forteresse du début du xiiie siècle – déjà reprise au cours de phases intermédiaires – à un nouveau programme résidentiel et défensif. Le château qui en résulte s’avère étrangement homogène, en dépit de techniques de mise en oeuvre très différentes suivant les époques, que cet article s’attache également à caractériser.
Notre-Dame de Fribourg-en-Brisgau. La chute des anges et la Genèse au portail nord du choeur
Authors: Flum Thomas
Published: October 2023

Das Figurenportal auf der Nordseite des Freiburger Münsters ist ein ikonographischer Einzelfall : sein figürliches Programm gründet auf Szenen der Schöpfungsgeschichte und das Tympanon zeigt in seinem Zentrum einen Engelssturz. Der Beitrag hinterfragt diese ikonographische Wahl und ihre Inszenierung, die in der Bildhauerkunst des 12. Jahrhunderts kein Beispiel kennt und die nun, im 14. Jh. in genau dieser Kirche erscheint. Der Beitrag beantwortet diese Frage, indem er Parallelen zu mehreren zeitgenössischen Texten aufzeigt, die die Geschichte von Adam und Eva und des Engelssturzes ausschmücken, wie zum Beispiel das Speculum humanae savationis, die Weltchroniken oder die Bilderbibeln. Diese handgeschriebenen, mit Buchmalereien geschmückten und in der Volkssprache und manchmal in der Region selbst verfassten Texte zeugen von einem Wandel der theologischen und ikonographischen Prioritäten.
Hygrobiella laxifolia (Hook.) Spruce (Hygrobiellaceae) dans les Alpes françaises
Authors: Chavoutier Leica , Hugonnot Vincent , Blanc-Tailleur Isabelle
Published: October 2023

Hygrobiella laxifolia (Hook.) Spruce est une hépatique peu signalée en France, où elle est probablement très rare, mais peut-être également sous-estimée. La découverte d’une nouvelle population dans le massif du Beaufortain, Alpes françaises, est l’occasion d’examiner le microhabitat de l’espèce et de préciser les caractéristiques morphologiques permettant une reconnaissance sur le terrain et sa distinction par rapport aux espèces ressemblantes. La comparaison des spécimens alpiens avec des spécimens d’herbier collectés dans les Scandes ou en Écosse permet de mettre en évidence une certaine plasticité morphologique, probablement à mettre en relation avec le microhabitat très particulier de l’espèce. Seules des colonies constituées majoritairement d’axes flagelliformes ont été observées en France, ce qui est interprété comme une adaptation à la violence du courant. A la limite sud-ouest de son aire de répartition, Hygrobiella laxifolia semble strictement cantonnée à des berges de torrents pentus, biotopes permettant une imbibition permanente des colonies.
Analyse de la liste des membres de la Société botanique de France de son origine (1854) à 2003 (150 ans)
Authors: Charpin André , Malecot Valéry
Published: October 2023

La liste des membres de la Société botanique de France publiée en 2007 a été précisée et fait l''objet ici d'analyses globales, en particulier sur le nombre d'admissions par décade, le genre des admis et, pour certaines décades, la répartition des admis par classe d''âge.
Redécouverte botanique et typifications des noms Aymenea De Faugère et Aymenea topiaria H. Aymen (Boraginaceae, Ehretioideae).
Authors: Maddi Franck A.
Published: October 2023

Jean-Baptiste Aymen (1728-1784) était un éminent médecin français, réputé naturaliste et fervent linnéen. Il entretenait une correspondance suivie avec les savants naturalistes de son époque, dont Bernard de Jussieu et Carl von Linné. En 1754, sur la base d’un échantillon d’une plante procurée par Bernard de Jussieu, le genre Aymenea a été proposé à Linné pour publication. Ce taxon n’a pas été retenu et reste un témoignage posthume en l’honneur d’Aymen. Sur la base de la diagnose et de ses illustrations, en se fondant sur les descriptions de genres proches, nous proposons de rattacher le genre Aymenea en synomymie avec Bourreria P. Browne, et le spécimen de Jussieu à B. baccata Raf. Nous désignons aussi un épitype du nom Aymenea topiaria H. Aymen dont le type est une illustration avec analyse.
Complément à la connaissance de la flore vasculaire de l'île Gargalu (Réserve naturelle de Scàndula, Corse occidentale)
Authors: Médail Frédéric , Pavon Daniel
Published: October 2023

Cette contribution dresse la liste des végétaux vasculaires observés sur l''île Gargalu (Corse occidentale), site classé en réserve intégrale au sein de la Réserve naturelle de Scàndula, suite à une mission effectuée en octobre 2020. Onze taxons indigènes non signalés jusqu''alors sur l''île ont été découverts. En considérant le bilan floristique des deux dernières missions (2014 et 2020), 152 taxons indigènes (espèces et sous-espèces) ont été inventoriés récemment sur l''île dont 107 dans le cadre de la mission d''octobre 2020. À l''échelle du site du golfe de Porto inscrit au Patrimoine mondial de l''UNESCO, Gargalu est l''île la plus intéressante sur le plan phytogéographique, avec 19 taxons à distribution restreinte dont de nombreux endémiques corses et 12 autres espèces végétales rares ou localisées en Corse.
Notes nomenclaturales relatives aux Aspleniaceae (Pteridophyta)-I
Authors: Boudrie Michel , Viane Ronald
Published: October 2023

Un nom nouveau est donné pour Asplenium ×confluens (T. Moore ex E. J. Lowe) Lawalrée, combinaison s’étant avérée être illégitime.
Compte-rendu de la mini-session à Fontainebleau du 10 au 12 mai 2019
Authors: Précigout Pierre-Antoine , Thommen Patrick , Estival Émilie , Bock Christian
Published: October 2023

Compte-rendu des herborisations menées lors de la mini-session à Fontainebleau (mai 2019)
Les statères à la légende ΟΛYΝΠΙϘ/ΚΟΝ et le début du monnayage des Éléens
Authors: Wojan Franck
Published: October 2023

Les débuts du monnayage d’argent des Éléens (Élide, Péloponnèse) sont étudiés à partir d’une série singulière de statères au type de Zeus aétophore lanceur de foudre et à la légende ΟΛYΝΠΙϘ/ ΚΟΝ (Seltman no 37 ; nos 72-73). Après en avoir décrit les particularités, nous chercherons à déterminer la datation et les raisons qui poussèrent cette jeune cité à se lancer dans «l’aventure monétaire » , probablement dans les années 470-460 av. J.-C.
Panhellenic Sanctuaries and Monetary Reform: Elis and Epidauros’ Adoption of the Symmachic Weight Standard
Authors: Post Ruben
Published: October 2023

Mints associated with the sanctuaries of Olympia and Epidauros transitioned from striking silver coinage on the Aiginetan weight standard to the symmachic standard, ca. 16% lighter, in the 250s or 240s BC, decades before other states in southern Greece. The light weight of these new coins dissuaded foreign visitors from removing them when they departed, stabilising the local money supply, while their types advertised the prestige of the local penteteric festivals amid increased competition from new festivals of similar status throughout the Mediterranean. This is an example of how Panhellenic sanctuaries could exert influence over monetary trends in the Hellenistic period.
A Die Study of the Gold and Silver Coinage of Berenike II, with Numismatic and Historical Commentary
Authors: Sewell-Lasater Tara
Published: October 2023

Coinage produced bearing the image of Berenike II, an early queen of the Ptolemaic dynasty, has become a source of contention for modern historians and numismatists. This coinage included denominations that were much larger than those previously or subsequently produced by the Ptolemies, and, since its categorization by Svoronos in 1904, the question of why has remained unanswered. This article will explore the results of an extensive die study completed on the gold and silver denominations of the Berenike coinage. The study analyzed 127 gold and 45 silver coins, the largest corpus of her coins ever collected. The results of the study allow several pertinent questions surrounding the reign of Berenike II and Ptolemy III to finally be confidently addressed, including where the coins were minted, possible reasons why they were minted, and the volume of the mintage. The confusion surrounding which standard these coins were minted on, Attic or Ptolemaic, is also analyzed.
An Attalid Overstrike and its Implications
Authors: Meadows Andrew
Published: October 2023

Cette note publie une nouvelle surfrappe d’une pièce attalide de Pergame sur une pièce séleucide d’Antioche. Elle en explore les implications chronologiques et soutient que la surfrappe confirme l’introduction du monnayage cistophorique dans les années 160. Les implications pour d’autres monnaies sont également explorées.
Le mariage éphémère d’Hélios et de Koré à Sardes
Authors: Strasser Jean-Yves
Published: October 2023

Sardis obtained under Elagabalus his third neokoria and Greek games of the highest rank, of which a coin once revealed a name : the Elagabalia. When she was twice neokoros, Sardis had two major competitions, associated with these neokoriai, then a third under Caracalla, the Koraia for Kore. The title of three times neokoros appears on the reverse side of bronzes issued under Sulpicius Hermophilos, in charge in 221/ 222 ; it is certainly that year that the emperor granted the neokoria and the games, which a bronze conserved at Harvard designates as Haleia Elagabalia. It is actually Sol Elagabalus who is honored and Helios is probably the deity whose Sardis then became neokoros, and not the emperor. Coins attest to the worship of Helios / Sol at the end of the reign and especially its association with the main deity of the city, Kore. But the

damnatio memoriae of Elagabalus puts an end to the neokoria, to the Haleia Elagabalia but also to the Koraia.
Il tesoretto di Taurasi e il fenomeno della tesaurizzazione alla fine della guerra greco-gotica
Authors: Mammatto Alfonso
Published: October 2023

L’article propose l’analyse préliminaire d’un trésor de nummi de bronze du milieu du vie siècle apr. J.-C. découvert à Tarausi (Campanie, Italie du Sud). À cette époque, la Campanie semble connaître un phénomène de thésaurisation, en particulier de ces petites dénominations en bronze. L’article tente de relier la localisation et la composition de divers trésors aux événements militaires qui ont affecté la région à la fin du conflit gréco-gothique en se fondant notamment sur les écrits d’Agathias qui prolongent le récit de Procope de Césarée.
A Signet Ring of Basileios, Eparch of Constantinople, from Porto Cesareo (LE), and the Photian Schism
Authors: Arthur Paul
Published: October 2023

In 2014, I was able to secure a Byzantine gold ring for the Italian people. It was found by a fisherman, off the coast at Porto Cesareo, Puglia, southern Italy. Study has shown that it is a signet ring that belonged to Basileios, imperial protospatharios and eparch of Constantinople during the period of the Photian schism (863-867). This paper describes the ring and its discovery as well as suggesting how it may relate to Basileios taking part in an embassy to the Papal court in Rome on behalf of the emperor Basil I.