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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

Second-order Sliding Mode Approaches for the Control of a Class of Underactuated Systems

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International Journal of Automation and computing 2015年第2期12卷 134-141页

作者： sonia Mahjoub Faical Mnif Nabil Derbel Advanced Control and Energy Management Laboratory University of SfaxSfax Engineering School Department of Electrical and Computer Engineering Sultan Qaboos University

In this paper, first-order and second-order sliding mode controllers for underactuated manipulators are proposed. Sliding mode control(SMC) is considered as an effective tool in different studies for control systems. However, the associated chattering phenomenon degrades the system performance. To overcome this phenomenon and track a desired trajectory, a twisting, a supertwisting and a modified super-twisting algorithms are presented respectively. The stability analysis is performed using a Lyapunov function for the proposed controllers. Further, the four different controllers are compared with each other. As an illustration, an example of an inverted pendulum is considered. Simulation results are given to demonstrate the effectiveness of the proposed approaches.

关键词： Underactuated manipulator sliding mode control twisting algorithm super-twisting algorithm inverted pendulum.

Divergent foraging behavior in a hybrid zone： Darwin＇s tree finches （Camarhynchus spp.） on Floreana Island

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Current Zoology 2015年第1期61卷 181-190页

作者： Katharina J. PETERS sonia KLEINDORFER School of Biological Sciences Flinders University GPO Box 2100 Adelaide 5001 Australia

Hybrid speciation is increasingly recognized as a mechanism for novel evolutionary trajectories. However, we know very little about the ecology of a contact zone that has arisen in sympatry. This study examines the foraging behavior and fitness of two species of Darwin＇s tree finches （Camarhynchus parvulus, C pauper） and hybrid offspring on Floreana Island. Previous study showed that the percentage of hybrids in the tree finch population increased from 19% in 2005 to 41% in 2010, and their body and beak size increased by -5% （parental phenotype did not change）. In 2005-2006, all three tree finch groups （two paren- tal species and hybrid birds） used the same foraging substrate, technique, and height. By 2010-2013, the small tree finch C. par- vulus had changed its foraging technique and the medium tree finch C. pauper had changed its foraging height. Both parental species had higher body condition when foraging at （divergent） mean foraging heights per species but hybrid birds did not. We discuss the implications of conserving forest to facilitate vertical niche expansion and the role of hybridization for genetic persis- tence [Current Zoology 61 （1）： 181-190, 2015].

关键词： Hybridization Speciation Adaptive radiation Conservation Scalesia Ecological niche

A Symbolic-Numeric Approach for Parametrizing Ruled Surfaces

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Journal of Systems Science & Complexity 2020年第3期33卷 799-820页

作者： PÉREZ-DÍAZ sonia SHEN Li-Yong Dpto.de Física y Matemáticas Universidad de Alcalá28871-Alcaláde HenaresMadridSpain School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China

This paper presents symbolic algorithms to determine whether a given surface(implicitly or parametrically defined)is a rational ruled surface and find a proper parametrization of the ruled ***,in practical applications,one has to deal with numerical objects that are given approximately,probably because they proceed from an exact data that has been perturbed under some previous measuring process or *** these numerical objects,the authors adapt the symbolic algorithms presented by means of the use of numerical *** authors develop numeric algorithms that allow to determine ruled surfaces"close"to an input(not necessarily ruled)surface,and the distance between the input and the output surface is computed.

关键词： Implicit representation numeric algorithm ruled surface standard parametrization

DeepWalk Based Influence Maximization (DWIM): Influence Maximization Using Deep Learning

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Intelligent Automation & Soft Computing 2023年第1期35卷 1087-1101页

作者： sonia Kapil Sharma Monika Bajaj Department of Information Technology Delhi Technological UniversityNew Delhi110039India Department of Computer Science University of DelhiNew Delhi110007India

Big Data and artificial intelligence are used to transform *** networking sites have given a new dimension to online *** media platforms help gather massive amounts of data to reach a wide variety of customers using influence maximization technique for innovative ideas,products and *** paper aims to develop a deep learning method that can identify the influential users in a *** method combines the various aspects of a user into a single *** a social network,the most influential user is the most trusted *** significant users are used for viral marketing as the seeds to influence other users in the *** proposed method combines both topical and topological aspects of a user in the network using *** proposed method is DeepWalk based Influence Maximization(DWIM).The proposed method was able tofind k influential nodes with computable time using the *** experiments are performed to assess the proposed algorithm,and centrality measures are used to compare the *** results reveal its performance that the proposed method canfind k influential nodes in computable *** can identify influential users,which helps viral marketing,outlier detection,and recommendations for different products and *** applying the proposed methodology,the set of seed nodes gives maximum influence measured with respect to different centrality measures in an increased computable time.

关键词： Deep learning inﬂuence maximization graph embedding deepwalk

Noise-induced hippocampal damage:potential mechanisms

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Neural Regeneration Research 2022年第3期17卷 563-564页

作者： sonia Jazmín Molina Laura Ruth Guelman Universidad de Buenos Aires Consejo Nacional de Investigaciones Científicas y TécnicasCentro de Estudios Farmacológicos y Botánicos(CEFyBOUBA-CONICET)Facultad de MedicinaBuenos AiresArgentina Universidad de Buenos Aires Facultad de Medicina1^(a) Cátedra de FarmacologíaBuenos AiresArgentina

Exposure to noise of high intensities(> 80 dB) is considered a stressful event and might produce both auditory and extra-auditory damage,including different central nervous system(CNS) *** the CNS,the hippocampus(HC),a structure related to several cognitive functions,has shown to be particularly susceptible to the effects of noise.

关键词： damage auditory injuries

Forest Biodiversity Assessment in Peruvian Andean Montane Cloud Forest

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Journal of Mountain Science 2012年第3期9卷 372-384页

作者： Alicia Ledo sonia Condés Iciar Alberdi Universidad Politécnica de Madrid.Escuela Técnica Superior de Ingenieros de Montes.Ciudad Universitaria sn.28040MadridSpain CIFOR-INIA Ctra.de La Corua Km 7.5 28040MadridSpain

Cloud forests are unusual and fragile habitats, being one of the least studied and least understood ecosystems. The tropical Andean dominion is considered one of the most significant places in the world as regards biological diversity, with a very high level of endemism. The biodiversity was analysed in an isolated remnant area of a tropical montane cloud forest known as the "Bosque de Neblina de Cuyas", in the North of the Peruvian Andean range. Composition, structure and dead wood were measured or estimated. The values obtained were compared with other cloud forests. The study revealed a high level of forest biodiversity, although the level of biodiversity differs from one area to another: in the inner areas, where human pressure is almost inexistent, the biodiversity values increase. The high species richness and the low dominance among species bear testimony to this montane cloud forest as a real enclave of biodiversity.

关键词： Andean Range Biodiversity Dead wood Montane forest Species composition Stand structure Tropical forest

A Survey of the Representations of Rational Ruled Surfaces

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Journal of Systems Science & Complexity 2021年第6期34卷 2357-2377页

作者： YUAN Chun-Ming PEREZ-DIAZ sonia SHEN Li-Yong KLMM Academy of Mathematics and Systems SciencesChinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China Grupo ASYNACS Dpto.de Fisica y MatematicasUniversidad de Alcala28871-Alcala de HenaresMadridSpain

The rational ruled surface is a typical modeling surface in computer aided geometric design.A rational ruled surface may have different representations with respective advantages and *** this paper,the authors revisit the representations of ruled surfaces including the parametric form,algebraic form,homogenous form and Plucker ***,the transformations between these representations are proposed such as parametrization for an algebraic form,implicitization for a parametric form,proper reparametrization of an improper one and standardized reparametrization for a general *** on these transformation algorithms,one can give a complete interchange graph for the different representations of a rational ruled *** rational surfaces given in algebraic form or parametric form not in the standard form of ruled surfaces,the characterization methods are recalled to identify the ruled surfaces from them.

关键词： Birational transformation characterization implicitization parametrization rational ruled surface reparametrization

Antioxidant effects of D-004, a lipid extract from the Roystonea regia fruit, on the plasma of healthy men

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Asian Journal of Andrology 2009年第3期11卷 385-392页

作者： Emesto lopez Vivian Molina Jose Illnait Ambar Oyarzfibal Lilia C. Femandez Rosa Mas Rafael Gamez Julio C. Fernandez sonia Jimenez Meilis Mesa Ivon Hollands Sarahi Mendoza Medical Surgical Research Centre Havana 6990 Cuba Centre of Natural Products from the National Centre for Scientific Research Havana 6880 Cuba

The aim of thisstudy was to conduct a randomized, double-blind and placebo-controlled study to investigate the effects of D-004, a lipid extract of the Roystonea regia fruit that prevents testosterone- and phenylepinephrine- induced prostate hyperplasia in rodents, on plasma oxidative markers in healthy men. We enrolled male volunteers （20-55 years） in good health and without lower urinary tract symptoms. Thirty-four eligible participants were randomized to placebo or D-004 （320 mg） capsules administered daily for 6 weeks. An interim check-up and a final visit were conducted after 3 and 6 weeks of therapy, respectively. Physical examinations were performed at each visit, and laboratory tests were performed at baseline and at treatment completion. Oxidative variables included plasma malondialdehyde （MDA）, total hydroxyperoxides （TOH）, sulphydryl （SH） groups and total antioxidant status （TAS）. We assessed treatment compliance and addressed adverse experiences （AEs） at weeks 3 and 6. At week 6, with D-004, the mean reductions of plasma MDA （26.7%）, TOH （18.8%） and SH groups （31.6%）, and the mean increase of TAS （35.3%） were significantly different from those of placebo （P 〈 0.001 for plasma TAS, P 〈 0.0001 for all other comparisons）. D-004 did not differ from the placebo in safety indicators. There were two withdrawals （both in the D-004 group）, with one due to dyspepsia （the only AE during the trial）. In conclusion, D-004 displayed antioxidant effects on plasma oxidative markers in healthy men, which was consistent with findings from laboratory experimental studies.

关键词： antioxidant benign prostate hyperplasia D-004 lipid peroxidation Roystonea regia