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Acta Mathematicae Applicatae Sinica 2011年第4期27卷 561-568页

作者： Kuo-Shou CHIU Manuel PINTO departamento de matemótica Facultad de Ciencias BósicasUniversidad Metropolitana de Ciencias de la EducacinJ.P.Alessandri 774SantiagoChile departamento de matemóticas Facultad de CienciasUniversidad de ChileCasilla 653SantiagoChile

A variation of parameters formula and Gronwall type integral inequality are proved for a differential equation involving general piecewise alternately advanced and retarded argument.

关键词： variation of parameters formula Gronwall integral inequality alternately advanced and retarded argument

The ρ-variation of the Hermitian Riesz Transform

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Acta Mathematica Sinica,English Series 2010年第10期26卷 1827-1838页

作者： Raquel CRESCIMBENI Francisco Javier MARTíN-REYES Alberto de la TORRE José L.TORREA departamento de matemática Universidad Nacional del Comahue Facultad de Economía y Administración departamento de Análisis matemático Facultad de Ciencias Universidad de Málaga facultad de ciencias Universidad Autónoma de Madrid ICMAT-CSIC-UAM-UCM-UC3M

In this paper we prove the behaviour in weighted Lp spaces of the oscillation and variation of the Hilbert transform and the Riesz transform associated with the Hermite operator of dimension 1. We prove that this operator maps LP（R, w（x）dx） into itself when w is a weight in the Ap class for 1 〈 p 〈 ∞. For p = 1 we get weak type for the A1 class. Weighted estimated are also obtained in the extreme case p = ∞.

关键词： Oscillation-p-variation-singular integral-Hermite operator

A Sufficient Condition for Kernel Perfectness of a Digraph in Terms of Semikernels Modulo F

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Acta Mathematica Sinica,English Series 2012年第2期28卷 349-356页

作者： Camino BALBUENA Hortensia GALEANA-SNCHEZ Mucuy-kak GUEVARA departament de matematica Aplicada III Universitat Politècnica de Catalunya Instituto de matemáticas Universidad Nacional Autónoma de México rea de la Investigación Científica Circuito Exterior Ciudad Universitaria facultad de ciencias Universidad Nacional Autónoma de México Universidad 3000 Circuito Exterior s/n Ciudad Universitaria

A kernel of a directed graph is a set of vertices which is both independent and absorbent. And a digraph is said to be kernel perfect if and only if any induced subdigraph has a kernel. Given a set of arcs F, a semikernel S modulo F is an independent set such that if some Sz-arc is not in F, then there exists a zS-arc. A sufficient condition on the digraph is given in terms of semikernel modulo F in order to guarantee that a digraph is kernel perfect. To do that we give a characterization of kernel perfectness which is a generalization of a previous result given by Neumann-lara [Seminucleos de una digrafica. Anales del Instituto de matematicas 2, universidad Nacional autSnoma de Mexico, 1971]. And moreover, we show by means of an example that our result is independent of previous known sufficient conditions.

关键词： Digraphs. kernel kernel-nerfect semikernel

On generalized impulsive piecewise constant delay differential equations

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Science China Mathematics 2015年第9期58卷 1981-2002页

作者： CHIU Kuo-Shou departamento de matemtica Facultad de Ciencias Bsicas Universidad Metropolitana de Ciencias de la Educación

A variation of parameters formula with Green function type and Gronwall type integral inequality are proved for impulsive differential equations involving piecewise constant delay of generalized type. Some results for piecewise constant linear and nonlinear delay differential equations with impulsive effects are *** include existence and uniqueness theorems, a variation of parameters formula, integral inequalities, the oscillation property and some applications.

关键词： impulsive differential equation piecewise constant delay of generalized type variation of parameters formula Gronwall integral i

Some Mathematical and Physical Remarks on Surreal Numbers

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Journal of Modern Physics 2016年第15期7卷 2164-2176页

作者： Juan Antonio Nieto facultad de ciencias fsico-matemáticas de la universidad autónoma de Sinaloa Culiacán México

We make a number of observations on Conway surreal number theory which may be useful, for further developments, in both mathematics and theoretical physics. In particular, we argue that the concepts of surreal numbers and matroids can be linked. Moreover, we established a relation between the Gonshor approach on surreal numbers and tensors. We also comment about the possibility to connect surreal numbers with supersymmetry. In addition, we comment about possible relation between surreal numbers and fractal theory. Finally, we argue that the surreal structure may provide a different mathematical tool in the understanding of singularities in both high energy physics and gravitation.

关键词： Surreal Numbers Supersymmetry Cosmology

(4 + 4)-Dimensional Space-Time as a Dual Scenario for Quantum Gravity and Dark Matter

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Journal of Applied Mathematics and Physics 2022年第3期10卷 688-702页

作者： Brandon Mariano Martínez-Olivas Juan Antonio Nieto Andrés Sandoval-Rodríguez facultad de ciencias fsico-matemáticas de la universidad autónoma Culiacán Sinaloa México

In this work, we make a number of proposals to explain how a world of (4 + 4)-dimensions can be useful for a better understanding of both dark matter and quantum gravity. The key idea is to look for some advantage of considering self-dual invariants in (4 + 4)-dimensions rather than in a separate context of (1 + 3)-dimensions or (3 + 1)-dimensions. In fact, we show that by considering the duality concept in (4 + 4)-dimensions we may provide an alternative meaning of a framework for loop quantum gravity. Moreover, considering the Dirac equation in (4 + 4)-dimensions for a particle without electric charge and mass, we show that when it is projected into the (1 + 3) and (3 + 1)-worlds may describe a system with electric charge and mass. We also discuss the relation between the three physical scenarios;(4 + 4)-world, black-holes and dark matter.

关键词： (4 + 4)-Dimensions Dark Matter Quantum Gravity

A charged star with geometric Karmarkar condition

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Communications in Theoretical Physics 2023年第8期75卷 139-149页

作者： Gabino Estevez-delgado Joaquin Estevez-delgado Rafael Soto-Espitia Antonio Rendón Romero Jorge Mauricio Paulin-Fuentes facultad de Químico Farmacobiología de la universidad Michoacana de San Nicolás de Hidalgo facultad de ciencias Físico matemáticas de la universidad Michoacana de San Nicolás de Hidalgo Edificio BCiudad Universitaria facultad de Ingeniería Civil de la universidad Michoacana de San Nicolás de Hidalgo Edificio A Ciudad Universitaria facultad de Ingeniería Mecánica de la universidad Michoacana de San Nicolás de Hidalgo Edificio W Ciudad Universitaria División Académica de ciencias Básicas de la universidad Juárez autónoma de Tabasco

In this paper,we analyse an analytical solution of the Einstein–Maxwell field equations that considers matter with anisotropic pressures in a static and spherically symmetric *** report the manner in which we obtained the solution,which is by means of the Karmarkar *** the model,we assume a state equation that describes the interaction of matter from quarks P=(c^(2)ρ-4B_(g))/3 and we consider the presence of electric charge,which can generate that the radial and tangential pressures are not *** a graphic manner,we analyse the physical properties of the model,taking as the observational data those of mass 1M⊙and radius7.69 km which were reported for the star Her *** charge values are found between 5.57×10^(18)C≤Q≤1.31×10^(20)C and the interval of the Bag constant Bg∈[118.7,122.13]MeV/fm^(3).Also,we show the stability of the configuration by means of the static stability criteria of Harrison–Zeldovich–Novikov((?M)/?ρc>0),as well as in regards to infinitesimal radial adiabatic perturbation,since the adiabatic indexγ>3.3 which guarantees the stability of the solution.

关键词： general relativity exact solutions anisotropic fluid Karmarkar condition

Towards a Surreal Spin Theory: Surreal Superstrings?

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Journal of Applied Mathematics and Physics 2022年第12期10卷 3586-3600页

作者： Juan Antonio Nieto Jesús Adrián Félix-Algandar facultad de ciencias fsico-matemáticas de la universidad autónoma de Sinaloa Culiacán Sinaloa México

We propose a surreal spin theory. Our basic mathematical tools are the dyadic rational number which is one of the key mathematical notions in surreal number theory. We argue that from the perspective of such surreal numbers, bosons and fermions, and therefore supersymmetry, are mere particular cases of a very much larger dyadic spin structure which include -spin (semionics), -spin and in general -spin, with m odd integer and n a positive natural number. Finally, we conjecture that this development could imply the existence of a surreal superstring theory.

关键词： Higher Spin Theory Surreal Numbers Dyadic Rationals

New Mathematical Tools for the Study of the DNA Structure

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Journal of Applied Mathematics and Physics 2021年第8期9卷 1896-1903页

作者： Juan Antonio Nieto Constanza Celia Nieto-Marín Nayeli Nieto-Marín Itzel Nieto-Marín facultad de ciencias fsico-matemáticas de la universidad autónoma de Sinaloa Culiacán Sinaloa México

We propose a number of new mathematical tools for the study of the DNA structure. In particular, we establish a connection between the DNA molecule and the Grassmann-Plücker coordinates, which, in both in mathematics... 详细信息

关键词： DNA Structure (4 + 4)-Dimensions Grassmann-Plücker Relations

Photoluminescence characteristics of soft PZT 53/47 ceramic doped at A and/or B sites

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Journal of Advanced Ceramics 2018年第2期7卷 109-116页

作者： M.D.DURRUTHY-RODRíGUEZ J.J.GERVACIO-ARCINIEGA M.HERNáNdeZ-GARCíA J.M.YánEZ-LIMóN universidad Nacional Evangélica departamento de Física Aplicada Instituto de CibernéticaMatemáticay FísicaCITMA Catedrático CONACYT-facultad de ciencias Físico matemáticas Benemérita Universidad Autónoma de Puebla CINVESTAV-Unidad Querétaro del IPN Libramiento Norponiente 2000Fracc.Real de Juriquilla

This study presents the photoluminescence characteristics of the PZT 53/47 system doped at A and/or B sites, with Nb(PZTN), la(PLZT), and Nb–la(PLZTN) in the concentration range from 0.2 to 1.0 molar fraction. The intensity of the emission bands of the system PZTN is two orders higher than the intensity of the emission bands of the systems PLZT and PLZTN, and these emission bands are located at 1.73 eV(718 nm), 2.56 eV(485 nm), and 2.93 eV(424 nm). The origin of the luminescence in these systems is associated with lead and oxygen vacancies produced during the sintering process. The results from X-ray diffraction(XRD) show a mixture of rhombohedral and tetragonal phases. The system PZTN shows a higher tetragonal phase concentration, while PLZT and PLZTN systems show a higher rhombohedral phase concentration. The cell volume shows an increase with dopant concentration only in the case of the PLZTN system. The band gap energy shows a small variation in the PZTN and PLZTN cases around 3.0 eV, a close value to the band gap energy of the pure PZT 53/47 sample. The system PLZT shows an increasing behavior until 4.41 eV for the higher dopant concentration.

关键词： photoluminescence PZT ceramics band structure X-ray diffraction(XRD)