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Inequalities for the Extended Best Polynomial Approximation Operator in Orlicz Spaces

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Acta Mathematica Sinica,English Series 2019年第2期35卷 185-203页

作者： Sonia ACINAS Sergio FAVIER Felipe ZO departamento de matemática Facultad de Ciencias y Exactas NaturalesUniversidad Nacional de La Pampa instituto de matemática aplicada san luis IMASLUniversidad Nacional de San Luis and CONICET departamento de matemática Universidad Nacional de San Luis

In this paper we pursue the study of the best approximation operator extended from L~Φ to L~φ, where φ denotes the derivative of the function Φ. We get pointwise convergence for the coefficients of the extended best approximation polynomials for a wide class of function f, closely related to the Calder′on–Zygmund class t_m^p(x) which had been introduced in 1961. We also obtain weak and strong type inequalities for a maximal operator related to the extended best polynomial approximation and a norm convergence result for the coefficients is derived. In most of these results, we have to consider Matuszewska–Orlicz indices for the function φ.

关键词： Orlicz spaces extended best polynomial approximation pointwise and norm convergence weak and strong type inequalities Orlicz indices

Stable Matchings in the Marriage Model with Indifferences

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Journal of the Operations Research Society of China 2021年第3期9卷 593-617页

作者： Noelia Juarez Jorge Oviedo instituto de matemática aplicada san luis IMASLUniversidad Nacional de San Luis and CONICETEjército de los Andes 950D5700HHW San LuisArgentina

For the marriage model with indifferences,we define an equivalence relation over the stable matching set.We identify a sufficient condition,the closing property,under which we can extend results of the classical model(without indifferences)to the equivalence classes of the stable matching set.This condition allows us to extend the lattice structure over classes of equivalences and the rural hospital theorem.

关键词： Stability Indifferences Lattice structure

Binary Operations for the Lattice Structure in a Many-to-Many MatchingModel

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Journal of the Operations Research Society of China 2021年第1期9卷 207-228页

作者： Paola Belén Manasero instituto de matemática aplicada san luis Universidad Nacional de San Luis and CONICETAv.Ejército de los andes 950D5700HHW San LuisArgentina

The lattice structure of the set of stable matchings in many-to-many matching model is well known in literature.If preferences of the agents are substitutable,this result can be obtained by fixed-point methods,for that purpose an algorithm for finding a fixed-point matching is defined.Since the fixed-point set equals the set of stable matchings,the latter has a lattice structure too.In this paper,we consider a many-to-many matching market where the preferences of firms satisfy substitutability and the law of aggregate demand,and workers have responsive preferences.In this many-to-many matching market,we explicitly compute for any pair of stable matchings the least upper bound and the greatest lower bound,without using fixed-point methods.

关键词： Many-to-many matching model Binary operations Lattice structure

Weighted Best Local Approximation

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Analysis in Theory and Applications 2016年第1期32卷 355-372页

作者： Segio Favier Claudia Ridolfi instituto de matematica aplicada san luis Conicet and Universidad Nacional de San Luis Ejercito de los Andes 950 San Luis Argentina

In this survey the notion of a balanced best multipoint local approximation is fully exposed since they were treated in the Lpspaces and recent results in Orlicz spaces. The notion of balanced point, introduced by Chu... 详细信息

关键词：最佳局部逼近 Orlicz空间加权 Lp空间平衡点

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Restabilization Process in Matching Markets with Workers Proposing

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Open Journal of Discrete Mathematics 2022年第4期12卷 101-112页

作者： Millán Beatriz instituto de matemática aplicada san luis IMASL Universidad Nacional de San Luis and CONICET San Luis Argentina departamento de matemática Universidad Nacional de San Juan San Juan Argentina

This paper is focused on the analysis, in the framework of lattice theory, of the matchings obtained from restabilization (after disruption) of stable matchings. When the disruption is due to entry workers or closure of firms the unemployed workers make offers to firms. The stable matching obtained is the firms-worst stable matching of the set of stable matchings that the firms weakly prefer to the initial stable matching (i.e., before being disrupted by changes in the population). More precisely, their position within the lattice of stable matchings is shown.

关键词： Stable Matchings Restabilization Lattice

Quasi-Optimal Convergence Rate of an AFEM for Quasi-Linear Problems of Monotone Type

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Numerical Mathematics(Theory,Methods and Applications) 2012年第2期5卷 131-156页

作者： Eduardo M.Garau Pedro Morin Carlos Zuppa departamento de matemática Facultad de Ingeniería Química and Instituto de Matemática Aplicada del Litoral(Universidad Nacional del Litoral and Consejo Nacional de Investigaciones Científicas y Técnicas).Güemes 3450.S3000GLN Santa FeArgentina departamento de matemática Facultad de Ciencias Físico Matemáticas y NaturalesUniversidad Nacional de San LuisChacabuco 918D5700BWT San LuisArgentina

We prove the quasi-optimal convergence of a standard adaptive finite element method(AFEM)for a class of nonlinear elliptic second-order equations of monotone type.The adaptive algorithm is based on residual-type a posteriori error estimators and Dörfler’s strategy is assumed for marking.We first prove a contraction property for a suitable definition of total error,analogous to the one used by Diening and Kreuzer(2008)and equivalent to the total error defined by Cascón et.al.(2008).This contraction implies linear convergence of the discrete solutions to the exact solution in the usual H1 Sobolev norm.Secondly,we use this contraction to derive the optimal complexity of the AFEM.The results are based on ideas from Diening and Kreuzer and extend the theory from Cascón et.***.to a class of nonlinear problems which stem from strongly monotone and Lipschitz operators.

关键词： quasilinear elliptic equations adaptive finite element methods optimality

Maximal Inequalities for the Best Approximation Operator and Simonenko Indices

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Analysis in Theory and Applications 2017年第3期33卷 253-266页

作者： Sonia Acinas Sergio Favier instituto de matematica aplicada san luis IMASLUniversidad Nacional de San Luis and CONICETEjercito de los Andes 950D5700HHW San LuisArgentina departamento de matematica Facultad de Ciencias Exactas y NaturalesUniversidad Nacional de La PampaL6300CLB Santa RosaLa PampaArgentina departamento de matematica Universidad Nacional de San LuisD5700HHW San LuisArgentina

In an abstract set up, we get strong type inequalities in L^p＋1 by assuming weak or extra-weak inequalities in Orlicz spaces. For some classes of functions, the number p is related to Simonenko indices. We apply the results to get strong inequal- ities for maximal functions associated to best Ф-approximation operators in an Orlicz space L^Ф.

关键词： Simonenko indices maximal inequalities best approximation.

PERTURBATION OF WAVELET AND GABOR FRAMES

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Analysis in Theory and Applications 2003年第3期19卷 238-254页

作者： Ivana Carrizo Sergio Favier Instituto de Matemática Aplicada San Luis Universidad Nacional de San Luis Instituto de Matemática Aplicada San Luis Universidad Nacional de San Luis Av.Ejército de Los Andes 950.5700 San LuisArgentinaAv.Ejército de Los Andes 950.5700 San LuisArgentina

In this work two aspects of theory of frames are presented: a side necessary condition on irregular wavelet frames is obtained, another perturbation of wavelet and Gabor frames is considered. Specifically, we present the results obtained on frame stability when one disturbs the mother of wavelet frame, or the parameter of dilatation, and in Gabor frames when the generating function or the parameter of translation are perturbed. In all cases we work without demanding compactness of the support, neither on the generating function, nor on its Fourier transform.

关键词： Riesz basis Gabor frame wavelet frame perturbation

Experimental approaches to select tree species for forest restoration:effects of light,water availability and interspecific competition in degraded areas

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Journal of Forestry Research 2022年第4期33卷 1197-1207页

作者： Johanna Croce Ernesto I.Badano Carolina B.Trigo Fernanda Martinez-Galvez Andrés Tálamo Laboratorio de Ecología aplicada a la Conservación Instituto de Bio y Geociencias del Noroeste ArgentinoConsejo de Investigaciones Científi cas y Técnicas-Universidad Nacional de SaltaAvenida Bolivia 51504400 SaltaArgentina IPICYT/División de Ciencias Ambientales Instituto Potosino de Investigación Científi ca y TecnológicaCamino a la Presa San José2055Colonia Lomas 4^(a)Sección78216 San Luis PotosíMéxico

Knowing what native trees can recr uit on degraded areas allows selecting the best species to restore these sites.However,as this information is not often available,experimentation is required before large-scale planting.This study used ex situ experiments to make these decisions on recruitment.Competition with r-strategist plants,excessive solar radiation and water shortage commonly impair tree recruitment in open habitats.The experiments focused on the interactions among these factors and were conducted with three pioneer species from seasonally dry forests of northwest Argentina,Anadenanthera colubrina,Ceiba chodatii and Jacaranda mimosifolia.Seeds of each species were sown at two light levels(sunlight/shade),two rainfall levels(full/reduced)and two levels of interspecific competition(with/without competitor)in a tree nursery.Seedling emergence and survival were monitored over a year and the results indicate that species differentially respond to varying levels of light and water.Seedlings of A.colubrina tolerated water shortages under elevated solar radiation,which are desirable features for forest restoration.Seedlings of C.chodatii tolerated shade and drought,suggesting that they require shading for establishing in open areas.However,J.mimosifolia seedlings neither tolerated full sunlight nor water shortages,suggesting that this species requires shading and regular watering if used in reforestation.Regardless of the effects of light and water,the survival of all species was reduced by interspecific competition.These results highlight the importance of experimentation for selecting the best species for forest restoration and can enhance the cost/benefit ratios of these actions.

关键词： Common-garden experiments Drought Ecological restoration Interspecific competition Seedling survival Shade