Advanced search


Knowledge area




17 results, page 1 of 2

Photon transport in binary photonic lattices

BLAS MANUEL RODRIGUEZ LARA Héctor Manuel Moya Cessa (2013)

We present a review on the mathematical methods used to theoretically study classical propagation and quantum transport in arrays of coupled photonic waveguides. We focus on analysing two types of binary photonic lattices where selfenergies or couplings are alternated. For didactic reasons, we split the analysis in classical propagation and quantum transport but all methods can be implemented, mutatis mutandis, in any given case. On the classical side, we use coupled mode theory and present an operator approach to Floquet-Bloch theory in order to study the propagation of a classical electromagnetic field in two particular infinite binary lattices. On the quantum side, we study the transport of photons in equivalent finite and infinite binary lattices by couple mode theory and linear algebra methods involving orthogonal polynomials. Curiously the dynamics of finite size binary lattices can be expressed as roots and functions of Fibonacci polynomials.

Article

Mathematical methods Electromagnetic field Binary lattices Photon transport CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA ÓPTICA ÓPTICA

Approximation for Transient of Nonlinear Circuits Using RHPM and BPES Methods

Luis Hernández Martínez (2013)

The microelectronics area constantly demands better and improved circuit simulation tools. Therefore, in this paper, rational homotopy perturbation method and Boubaker Polynomials Expansion Scheme are applied to a differential equation from a nonlinear circuit. Comparing the results obtained by both techniques revealed that they are effective and convenient.

Article

Nonlinear circuits RHPM BPES methods CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA ELECTRÓNICA ELECTRÓNICA

THE CHROMOSPHERIC SOLAR MILLIMETER-WAVE CAVITY ORIGINATES IN THE TEMPERATURE MINIMUM REGION

Victor De la Luz (2013)

We present a detailed theoretical analysis of the local radio emission at the lower part of the solar atmosphere. To accomplish this, we have used a numerical code to simulate the emission and transport of high-frequency electromagnetic waves from 2 GHz up to 10 THz. As initial conditions, we used VALC, SEL05, and C7 solar chromospheric models. In this way, the generated synthetic spectra allow us to study the local emission and absorption processes with high resolution in both altitude and frequency. Associated with the temperature minimum predicted by these models, we found that the local optical depth at millimeter wavelengths remains constant, producing an optically thin layer that is surrounded by two layers of high local emission. We callthis structure the Chromospheric Solar Millimeter-wave Cavity (CSMC). The temperature profile, which features temperature minimum layers and a subsequent temperature rise, produces the CSMC phenomenon. The CSMCshows the complexity of the relation between the theoretical temperature profile and the observed brightness temperature and may help us to understand the dispersion of the observed brightness temperature in the millimeter wavelength range.

Article

Methods: numerical Radiation mechanisms: thermal Radiative transfer Stars: chromospheres Sun: chromosphere Sun: radio radiation CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA ASTRONOMÍA Y ASTROFÍSICA ASTRONOMÍA Y ASTROFÍSICA

ON THE FATE OF THE MATTER REINSERTED WITHIN YOUNG NUCLEAR STELLAR CLUSTERS

GUILLERMO TENORIO TAGLE SERGIY SILICH (2013)

This paper presents a hydrodynamical model describing the evolution of the gas reinserted by stars within a rotating young nuclear star cluster (NSC). We explicitly consider the impact of the stellar component on the flow by means of a uniform insertion of mass and energy within the stellar cluster. The model includes the gravity force of the stellar component and a central supermassive black hole (SMBH), and accounts for the heating from the central source of radiation and the radiative cooling of the thermalized gas. By using a set of parameters typical for NSCs and SMBHs in Seyfert galaxies, our simulations show that a filamentary/clumpy structure is formed in the inner part of the cluster. This “torus” is Compton-thick and covers a large fraction of the sky (as seen from the SMBH).In the outer parts of the cluster a powerful wind is produced that inhibits the infall of matter from larger scales andthus the NSC–SMBH interplay occurs in isolation.

Article

Accretion, accretion disks Galaxies: active Galaxies: star clusters: general Hydrodynamics Methods: numerical CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA ASTRONOMÍA Y ASTROFÍSICA ASTRONOMÍA Y ASTROFÍSICA

Yield estimation of forage oat (Avena sativa L.) Chihuahua variety: ruler and plate methods.

SERGIO IBAN MENDOZA PEDROZA PERPETUO ALVAREZ VAZQUEZ ELISEO SOSA MONTES MARIA DE LOS ANGELES MALDONADO PERALTA JONATHAN RAUL GARAY MARTINEZ (2021)

Objetive: To analyze forage estimations with the direct method and the plant height.

Design/methodology/approach: The treatments were the plants age, assessed in a random block design. Simple linear

regressions were carried out and adjusted using the SPSS statistical software.

Article

Estimation methods plant height forage yield CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CIENCIAS AGRARIAS OTRAS ESPECIALIDADES AGRARIAS

Study of Thermal Properties on the Different Layers Composing a Commercial Ceramic Tile

JOSE DE JESUS AGUSTIN FLORES CUAUTLE GEMIMA LARA HERNANDEZ ALFREDO CRUZ OREA CESAR ADRIAN HERNANDEZ AGUILAR CARLOS OMAR GONZALEZ MORAN JOSE GUADALUPE MIRANDA HERNANDEZ OSCAR OSVALDO SANDOVAL GONZALEZ (2019)

In this study the thermal conductivity of a commercial ceramic is determined considering that this property is an essential factor on the building materials. This is the primary indicator of the material suitableness for energy transfer, considering that this kind of construction supplies has many applications as thermal insulations. In this sense, we consider that a commercial tile is usually composed of three layers: substrate, a so-called engine layer, and an enamel layer. Likewise, the thermal properties of the different layers were obtained individually by using two photothermal techniques on the ceramic material; the ceramic tile density was obtained using the Archimedes method. The calculated values show a wide range of thermal conductivity values for the different layers, ranging from1.3 to 4 W m¡1K¡1.

Article

Thermal properties ceramic tile photothermal methods BIOLOGÍA Y QUÍMICA

Artificial Intelligence Methods and Their Applications in Civil Engineering

GONZALO MARTINEZ BARRERA GENCEL OSMAN AHMET BEYCIOGLU serkan subasi NELLY MA DE LA PAZ GONZALEZ RIVAS (2015)

Simulation of material properties generally involves the development of a mathematical model derived from experimental data. In structural mechanics and construction materials contexts, recent experiments have reported that fuzzy logic (FL), artificial neural networks (ANNs), genetic algorithm (GA), and fuzzy genetic (FG) may offer a promising alternative. They are known as artificial intelligence (AI). In civil engineering, AI methods have been extensively used in the fields of civil engineering applications such as construction management, building materials, hydraulic, optimization, geotechnical and transportation engineering. Many studies have examined the applicability of AI methods to estimate concrete properties. This chapter described the principles of FL methods that can be taught to engineering students through MATLAB graphical user interface carried out in a postgraduate course on Applications of Artificial Intelligence in Engineering, discussed the application of Mamdani type in concrete technology and highlighted key studies related to the usability of FL in concrete technology.

Book part

Methods, Applications Civil Engineering Artificial intelligence INGENIERÍA Y TECNOLOGÍA