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Radicals and Kothe’s Conjecture for Skew PBW Extensions

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Communications in Mathematics and Statistics 2021年第2期9卷 119-138页

作者： Armando Reyes Hector Suarez departamento de matematicas Universidad Nacional de ColombiaSede BogotaColombia escuela de Matemáticas y Estadística Universidad Pedagogica y Tecnológica de ColombiaSede TunjaColombia

The aim of this paper is to investigate different radicals(Wedderburn radical,lower nil radical,Levitzky radical,upper nil radical,the set of all nilpotent elements,the sum of all nil left ideals)of the noncommutative rings known as skew Poincare–Birkhoff–Witt *** characterize minimal prime ideals of these rings and prove that the Kothe’s conjecture holds for these ***,we establish the transfer of several ring-theoretical properties(reduced,symmetric,reversible,2-primal)from the coefficients ring of a skew PBW extension to the extension itself.

关键词： Armendariz rings Kothe’s conjecture Skew PBW extensions

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The _(ΛΛ)~4n system

Chinese Physics C 2017年第7期41卷 61-66页

作者： H.Garcilazo A.Valcarce J.Vijande escuela superior de ffsica y matematicas Instituto Politecnico Nacional Edificio 9 07738 Mexico D.F. Mexico departamento de ffsica Fundamental and IUFFyM Universidad de Salamanca E-37008 Salamanca Spain Unidad Mixta de Investigacion en Radioffsica e Instrumentacion Nuclear en Medicina (IRIMED) Instituto de Investigacion Sanitaria La Fe (IIS-La Fe)-Universitat de Valencia (UV) and IFIC (UV-CSIC) Valencia Spain

Using local central yukawa-type Malfliet-Tjon interactions reproducing the low-energy parameters and phase shifts of the nn system, and the latest updates of the nΛ and ΛΛ Nijmegen ESC08c potentials, we study the possible existence of a ^4 ΛΛn bound state. Our results indicate that the ^4 ΛΛn is unbound, being just above *** discuss the role played by the -1S0 nn repulsive term of the yukawa-type Malfliet-Tjon interaction.

关键词： baryon-baryon interactions few-body systems

Phase transitions in four-dimensional AdS black holes with a nonlinear electrodynamics source

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Communications in Theoretical Physics 2021年第12期73卷 119-128页

作者： Ramon Becar P A Gonzalez Joel Saavedra yerko Vasquez Bin Wang departamento de Ciencias matematicas y Fisicas Universidad Catolica de TemucoMontt 56Casilla 15-DTemucoChile Facultad de Ingenieria y Ciencias Universidad Diego PortalesAvenida Ejercito Libertador 441Casilla 298-VSantiagoChile Instituto de ffsica Pontificia Universidad Catolica de ValparaisoCasilla 4950ValparaisoChile departamento de ffsica Facultad de CienciasUniversidad de La SerenaAvenida Cistemas 1200La SerenaChile Center for Gravitation and Cosmology College of Physical Science and TechnologyYangzhou UniversityYangzhou 225009China

In this work we consider black hole solutions to Einstein’s theory coupled to a nonlinear powerlaw electromagnetic field with a fixed exponent *** study the extended phase space thermodynamics in canonical and grand canonical ensembles,where the varying cosmological constant plays the role of an effective thermodynamic *** examine thermodynamical phase transitions in such black holes and find that both first-and second-order phase transitions can occur in the canonical ensemble while,for the grand canonical ensemble,Hawking-Page and second-order phase transitions are allowed.

关键词： black hole thermodynamics nonlinear Maxwell

Alternative approaches for estimating missing climate data:application to monthly precipitation records in South- Central Chile

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Forest Ecosystems 2018年第4期5卷 390-399页

作者： Alonso Barrios Guillermo Trincado Rene Garreaud escuela de Graduados Facultad de Ctencias Forestales y Recursos Naturales Universidad Austral de ChileBox 567ValdiviaChile departamento de Ciencias Forestales Facuitad de Ingenieria ForestalUnlversidad del Tolima Box 6299 Ibague Colombia Instituto de Bosques y Sociedad Facultad de Ciencias Forestales y Recursos NaturalesUniversidad Austraide ChileBox 567 ValdiviaChile departamento de Geofistca Facultad de Ciencias Fisicas y MatematicasUniversidad de ChileSantiagoChile

Background: Over the last decades interest has grown on how climate change impacts forest resources. However,one of the main constraints is that meteorological stations are riddled with missing climatic data. This study compared five approaches for estimating monthly precipitation records: inverse distance weighting(IDW), a modification of IDW that includes elevation differences between target and neighboring stations(IDW_m), correlation coefficient weighting(CCW), multiple linear regression(MLR) and artificial neural networks(ANN).Methods: A complete series of monthly precipitation records(1995-2012) from twenty meteorological stations located in central Chile were used. Two target stations were selected and their neighboring stations, located within a radius of25 km(3 stations) and 50 km(9 stations), were identified. Cross-validation was used for evaluating the accuracy of the estimation approaches. The performance and predictive capability of the approaches were evaluated using the ratio of the root mean square error to the standard deviation of measured data(RSR), the percent bias(PBIAS), and the NashSutcliffe efficiency(NSE). For testing the main and interactive effects of the radius of influence and estimation approaches,a two-level factorial design considering the target station as the blocking factor was ***: ANN and MLR showed the best statistics for all the stations and radius of influence. However, these approaches were not significantly different with IDW_m. Inclusion of elevation differences into IDW significantly improved IDW_m estimates. In terms of precision, similar estimates were obtained when applying ANN, MLR or IDW_m, and the radius of influence had a significant influence on their estimates, we conclude that estimates based on nine neighboring stations located within a radius of 50 km are needed for completing missing monthly precipitation data in regions with complex ***: It is concluded that approaches based on ANN

关键词： Climatological data Cross-validation Artificial neural networks Multiple linear regression

GLOBAL SOLUTIONS TO A HyDRODyNAMIC MOdeL FOR SEMICONDUCTORS WITH VELOCITy RELAXATION

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Acta Mathematica Scientia 2023年第2期43卷 975-980页

作者：王先婷陆云光 Richard de la cruz 尤国桥 department of Mathematics Wuxi Institute of TechnologyWuxi 214121China School of Mathematics Hangzhou Normal UniversityHangzhou 311121China escuela de matematicas y Estadistica Universidad Pedagógica y Tecnológica de Colombia 999076Colombia School of Mathematics Nanjing Audit UniversityNanjing 210000China

In this paper,we apply the method given in the paper“Zero relaxation time limits to a hydrodynamic model of two carrier types for semiconductors”(Mathematische Annalen,2022,382:1031–1046)to study the Cauchy problem for a one dimensional inhomogeneous hydrodynamic model of two-carrier types for semiconductors with the velocity relaxation.

关键词： global L solution hydrodynamic model two-carrier types velocity relaxation

Symmetry in optics and photonics:a group theory approach

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Science Bulletin 2018年第4期63卷 244-251页

作者： B.M.Rodriguez-Lara Ramy EI-Ganainy Julio Guerrero Tecnologico de Monterrey.escuela de Ingenieria y Ciencias Monterrey 64849Mexico Instituto Nacional de Astrofisica Optica y Electr6nicaPueblaCP 72840Mexico department of Physics and Hexes Center for Quantum Phenomena Michigan Technological UniversityHoughton.MI 49931USA departamento de matematicas Facultad de Ciendas Experimentales y de la SaludCampus Las LagunillasUniversidad de Jaen23071JaenSpain departamento de Ingenierfa y Tecnologia de Computadores Facultad de lnformdticaCampus EspinardoUnivesidad de Murcia30100 MurciaSpain

Group theory(GT) provides a rigorous framework for studying symmetries in various disciplines in physics ranging from quantum field theories and the standard model to fluid mechanics and chaos theory. To date, the application of such a powerful tool in optical physics remains limited. Over the past few years however, several quantum-inspired symmetry principles(such as parity-time invariance and supersymmetry) have been introduced in optics and photonics for the first time. despite the intense activities in these new research directions, only few works utilized the power of group theory. Motivated by this status quo, here we present a brief overview of the application of GT in optics, deliberately choosing examples that illustrate the power of this tool in both continuous and discrete setups. We hope that this review will stimulate further research that exploits the full potential of GT for investigating various symmetry paradigms in optics, eventually leading to new photonic devices.

关键词： Group theoryHelmholtz equationDiscrete opticsParity-time (PT) symmetry

Relaxation Limit for Aw-Rascle System

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Journal of Partial Differential Equations 2014年第2期27卷 166-175页

作者： de LA CRUZ GUERRERO Richard A JUAJIBIOy Juan C RENDON Leonardo departamento de matematicas Universidad Nacional de Colombia Bogota D. C.Colombia. escuela de matematicas y Estadistica Universidad Pedagogica y Tecnologica deColombia Tunja Colombia.

We study the relaxation limit for the Aw-Rascle system of traffic flow. For this we apply the theory of invariant regions and the compensated compactness method to get global existence of Cauchy problem for a particular Aw-Rascle system with source, where the source is the relaxation term, and we show the convergence of this solutions to the equilibrium state.

关键词： Aw-Rascle system relaxation term compensated compactness invariant regions.

Synthesis of Hydrothermally Grown Zinc Oxide Nanowires

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Journal of Chemistry and Chemical Engineering 2012年第1期6卷 61-64页

作者： Concepcioen Mejia-Garcia Elvia Diaz-Valdes Gerardo Ortega-Cervantes Esteban Basurto-Cazares departamento de Fisica Escuela Superior de Fisica y Matematicas de Instituto Politecnico Nacional Unidad Adolfo Lopez MateosMexico D. F. 07738 Mexico

We report the synthesis ofZnO nanowires grown on glass by spin coating and using a commercial microwave oven. 10 mM solutions of zinc acetate dehydrate and 12propanol were spin coated on glass at 2000 rpm for 60 s. A seed layer was obtained after three layers of spin coating. Vertical ZnO nanowires were then grown by dipping the substrate in an equimolar solution of zinc nitrate hexahydrate and hexamethylenetetramine subsequently, films were heated with a commercially microwave oven at different power settings （140, 350 and 700 W）. The ZnO nanowires were characterized optically and morphologically. Scanning electron microscopy analysis showed that the size of ZnO nanowires was 50 nm in diameter and 500 nm in length. XRD patterns and IR spectra revealed the presence of Zn（OH）2 on the films, when low power in the microwave oven was utilized. The ZnO nanowires bandgap energy was obtained from optical transmission spectra.

关键词： ZnO nanowires Scanning Electron Microscopy X-Ray Diffraction IR optical transmission.

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评论：“边界振动的微腔中的二能级原子”

物理学报 2014年第6期63卷 445-445页

作者： A.Zuniga-Segundo H.Moya-Cessa Instituto Politecnico Nacional Escuela Superior de Fisicay Matematicas Edificio Unidad Profesional Adolfo Lopez Mateos 07738 M&#233 xico D.F. Mexico Instituto Nacional de Astrofisica Opticay Electronica Apartado postal 51y 216 72000 Puebla Pue. Mexico

在曲照军等的文章中作者声称他们能够解决腔场影响原子问题。在此我们显示出既然他们用于得到相互作用表象的哈密顿的变换不完备所以他们没有解决该问题。

关键词：二能级原子微腔振动边界评论相互作用子问题哈密顿