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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

Estimation of radiated energy using the EGF technique: what should be the upper limit of integration in the frequency domain?

Shri Krishna Singh (2007)

The empirical Green's function (EGF) technique is frequently used to estimate the radiated seismic energy, ER, of an earthquake. An approximation of the moment-rate spectrum, M0(f), of the target earthquake is obtained from the ratio of the spectrum of the target earthquake to the spectrum of the EGF earthquake, and the radiated seismic energy is computed by integrating f2M0 2(f) over frequency f. The choice of the upper limit of integration, fu, is critical. In this note we show that the optimum choice of fu, for the ω2-source model is given by fu/fc1∼ fc2/fc1, where fc1 and fc2 are the corner frequencies of the target and the EGF earthquakes, respectively. This result provides a useful guide in the application of the EGF technique to obtain a reliable estimate of the radiated seismic energy.

Article

TERREMOTOS ANÁLISIS EMPÍRICO MÉTODO DE ESTIMACIÓN FUNCIÓN VERDE ANÁLISIS DE FIABILIDAD SISMICIDAD Earthquake Empirical analysis Estimation method Green function Reliability analysis Seismicity CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA CIENCIAS DE LA TIERRA Y DEL ESPACIO GEOFÍSICA SISMOLOGÍA Y PROSPECCIÓN SÍSMICA concept8601 Seismology

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

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

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

Submm/mm Galaxy Counterpart Identification Using a Characteristic Density Distribution

Itziar Aretxaga David Hughes (2013)

We present a new submm/mm galaxy counterpart identification technique whichbuilds on the use of Spitzer IRAC colors as discriminators between likely counter-parts and the general IRAC galaxy population. Using 102 radio- and SMA-confirmedcounterparts to AzTEC sources across three fields (GOODS-N, GOODS-S, and COSMOS), we develop a non-parametric IRAC color-color characteristic density distribution (CDD), which, when combined with positional uncertainty information vialikelihood ratios, allows us to rank all potential IRAC counterparts around SMGsand calculate the significance of each ranking via the reliability factor. We reportall robust and tentative radio counterparts to SMGs, the first such list available forAzTEC/COSMOS, as well as the highest ranked IRAC counterparts for all AzTECSMGs in these fields as determined by our technique. We demonstrate that the technique is free of radio bias and thus applicable regardless of radio detections. For observations made with a moderate beamsize (∼18′′), this technique identifies ∼85 percent of SMG counterparts. For much larger beamsizes (≳30′′), we report identificationrates of 33-49 per cent. Using simulations, we demonstrate that this technique is animprovement over using positional information alone for observations with facilities such as AzTEC on the LMT and SCUBA-2 on JCMT.

Article

Submillimetre: galaxies Radio continuum: galaxies Infrared: galaxies Galaxies: high redshift Techniques: photometric Methods: data analysis CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA ASTRONOMÍA Y ASTROFÍSICA RADIOASTRONOMÍA RADIOASTRONOMÍA

Disk Mass-to-Light ratio distribution from stellar population synthesis: Application to rotation curve decomposition of NGC 5278 (KPG 390 A).

ERIC EMMANUEL MARTINEZ GARCIA (2013)

In this work we extend the study on the mass distribution of the spiral galaxy NGC 5278, performing 1D and 2D (GALFIT) bulge-disk decomposition to determine which components constitute the baryonic mass in this galaxy. Our analysis does not detect any bulge, instead we find a bright source, probably related with the central AGN, and an exponential disk. We fix the stellar disk contribution to the rotation curve (RC) with broad band photometric observations and population synthesis models, to obtain the 2D mass distribution of the stellar disk. In particular, for NGC 5278, we find that the typical assumption of considering the mass-to-luminosity ratio (M/L) of the disk as constant along the galactocentric radius is not valid. We also extract a baryonic RC from the mass profile, to determine the inability of this baryonic RC (also taking into account ± 30% errors in the disk mass), to fit the entire RC. We perform the RC decomposition of NGC 5278 considering the determined baryonic RC and four types of dark matter (DM) halo: Hernquist, Burkert, Navarro, Frenk, & White and Einasto. Our results determine that Hernquist DM halo better models our observed RC in the case of disk mass Md = 5.6 × 10¹⁰ Mʘ and also with less 30% disk mass. In the case of more 30% disk mass the cored Einasto (n < 4) DM halo is the best fitting model.

Article

Galaxies: interactions (Cosmology:) dark matter Galaxies: kinematics and dynamics Methods: data analysis Techniques: interferometric Techniques: imaging spectroscopy CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA ASTRONOMÍA Y ASTROFÍSICA ASTRONOMÍA Y ASTROFÍSICA