3,029 research outputs found

    Efficient Calculation of the Green's Functions for Multilayered Shielded Cavities with Right Isosceles-Triangular Cross-Section

    Get PDF
    An efficient calculation of the Green’s functions inside multilayered shielded cavities with right isosceles-triangular cross-section is presented. The method is entirely developed in the spatial domain, and it is based on image theory. The idea is to use the spatial-domain Green’s functions inside a multilayered shielded square box, in order to accurately obtain the Green’s functions for the right isosceles-triangular cavity. Image theory is then used to enforce the boundary conditions along the non-equal side of the triangle. It is shown that the new algorithm is very robust, with limited computational effort. Resonance frequencies and potential patterns of a triangular cavity have been calculated and compared with those obtained by other techniques, showing very good agreement. Finally, a transversal filter inside a multilayered triangular-shaped cavity is designed, manufactured and tested using the developed technique.This work was partially supported by the Spanish Ministry of Education and Science under Grant FPU-AP2006-015 and with the Project TEC2007-67630-C03-02

    Propuesta para la definición de los procesos de abastecimiento, producción y distribución de una cerveza artesanal en el municipio de Funza y sus alrededores

    Get PDF
    EmprendimientoEste proyecto de emprendimiento reúne los conocimientos de Ingeniería Industrial y los aplica para realizar un estudio de mercado que permita determinar los procesos de abastecimiento, producción y distribución de una cerveza artesanal en el municipio de Funza, ya que este sector tiene bajo consumo y hoy en día la cerveza artesanal está en auge en Bogotá. Con los resultados del estudio y la información recolectada por medio de encuestas, se logra obtener la demanda, marca, presentación, mercado objetivo y establecer el nivel de aceptación del lanzamiento de un producto artesanal llamado CACHARRA, el cual es una cerveza elaborada a base de Jengibre.INTRODUCCIÓN 1. GENERALIDADES 2. ANALISIS DE MERCADO 3. PUBLICIDAD 4. CANAL DE COMERCIALIZACIÓN Y DISTRIBUCIÓN 5. VIABILIDAD FINANCIERA 6. CONCLUSIONES 7. RECOMENDACIONES BIBLIOGRAFÍA ANEXOSPregradoIngeniero Industria

    On bubble clustering and energy spectra in pseudo-turbulence

    Full text link
    3D-Particle Tracking (3D-PTV) and Phase Sensitive Constant Temperature Anemometry in pseudo-turbulence--i.e., flow solely driven by rising bubbles-- were performed to investigate bubble clustering and to obtain the mean bubble rise velocity, distributions of bubble velocities, and energy spectra at dilute gas concentrations (α2.2\alpha \leq2.2%). To characterize the clustering the pair correlation function G(r,θ)G(r,\theta) was calculated. The deformable bubbles with equivalent bubble diameter db=45d_b=4-5 mm were found to cluster within a radial distance of a few bubble radii with a preferred vertical orientation. This vertical alignment was present at both small and large scales. For small distances also some horizontal clustering was found. The large number of data-points and the non intrusiveness of PTV allowed to obtain well-converged Probability Density Functions (PDFs) of the bubble velocity. The PDFs had a non-Gaussian form for all velocity components and intermittency effects could be observed. The energy spectrum of the liquid velocity fluctuations decayed with a power law of -3.2, different from the 5/3\approx -5/3 found for homogeneous isotropic turbulence, but close to the prediction -3 by \cite{lance} for pseudo-turbulence

    Photocatalytic Performance of Titanates with Formula MTiO3 (M= Fe, Ni, and Co) Synthesized by Solvo-Combustion Method

    Get PDF
    This work reports the synthesis of a variety of materials with an ilmenite-type structure MTiO3 formula, where M= Fe, Co, and Ni, these materials were synthesized by the method of solvo-combustion, a simple and rapid method. These materials were characterized by X-ray Diffraction (XRD), scanning electron microscopy (SEM), FT-IR spectroscopy, thermogravimetric analysis (TGA/DTA), surface area determination by the BET method and analysis of particle size. The photocatalytic activity was measured in the degradation reactions of Rhodamine B (rhB) and tetracycline (TC). The results show that the crystallinity and surface area are factors that influence significantly on the photocatalytic activity of the synthesized titanates. Keywords: Non-aqueous solution, Characterization, Titanates, solvo-combustion, organic pollutants, photocatalysi

    La ficción en la televisión generalista norteamericana y la representación de (nuevas) masculinidades

    Get PDF
    The text offers a tour through different representations of male characters in American generalist television that are beyond the classical representation of the male characters that were depicted as traditionally strong characters, courageous and machos. Considering how American television fiction has a maximum expan­sion –not only in the US but, also for its strong presence in all Western television, in Spain– we could see the impact that these representations can make in the public in order to build new identitarian points of referen­ce of the masculine, masculinity and virility.En el texto se hace un recorrido por diferentes representaciones de personajes masculinos en la televi­sión generalista norteamericana que se escapan a la representación clásica de los personajes masculi­nos que tradicionalmente eran representados como personajes fuertes, valerosos y machos. Teniendo en cuenta cómo la ficción televisiva norteamericana cuenta con una máxima expansión –no solamente en Estados Unidos sino también, por su gran presencia en todas las televisiones occidentales, en España– podríamos ver la repercusión que dichas representaciones pueden tener en los públicos en orden a cons­truir nuevos imaginarios y nuevas referencias identitarias de lo masculino, la masculinidad y la virilidad

    Machine learning quantum field theory with local probes

    Full text link
    We propose the use of machine learning techniques to address the problem of local measurements in quantum field theory. In particular we discuss how neural networks can efficiently process measurement outcomes from local probes to determine both local and non-local features of the quantum field. As toy examples we show: a) how a particle detector distinguishes boundary conditions imposed on the field without the need of signals propagating from them, and b) how detectors can determine the temperature of the quantum field without thermalizing with it. We discuss how the formalism proposed can be used for any kind of local measurement on a quantum field and, by extension, to local measurements of non-local features in many-body quantum systems.Comment: 9 pages (4 pages of appendices), 2 Figures, RevTeX 4.

    Genetic diversity and genetic structure of an endemic Mexican Dusky Rattlesnake (Crotalus triseriatus) in a highly modified agricultural landscape: implications for conservation

    Get PDF
    ArtículoIt is necessary to determine genetic diversity of fragmented populations in highly modified landscapes to understand how populations respond to land-use change. This information will help guide future conservation and management strategies. We conducted a population genetic study on an endemic Mexican Dusky Rattlesnake (Crotalus triseriatus) in a highly modified landscape near the Toluca metropolitan area, in order to provide crucial information for the conservation of this species. There was medium levels of genetic diversity, with a few alleles and genotypes. We identified three genetically differentiated clusters, likely as a result of different habitat cover type. We also found evidence of an ancestral genetic bottleneck and medium values of effective population size. Inbreeding coefficients were low and there was a moderate gene flow. Our results can be used as a basis for future research and C. triseriatus conservation efforts, particularly considering that the Trans-Mexican Volcanic Belt is heavily impacted by destructive land-use practices

    Multipactor effect in a parallel-plate waveguide partially filled with magnetized ferrite

    Get PDF
    The aim of this paper is the analysis of the multipactor effect in a parallel-plate waveguide when a ferrite slab, transversally magnetized by a static magnetic field parallel to the waveguide walls, is present. Employing an in-house developed code, numerical simulations are performed to predict the multipactor radio frequency voltage threshold in such a ferrite-loaded waveguide. Variations of the ferrite magnetization field strength and the ferrite slab height are analyzed. Effective electron trajectories are also shown for a better understanding of the breakdown phenomenon, finding different multipactor regimes

    Geometrical optimization of thermoforming continuous fibers reinforced thermoplastics with Finite Element Models: A case study

    Get PDF
    The manufacturing of thermoformed components of continuous fiber-reinforced thermoplastics (CFRTPs) relies on an optimization process owing to a demand for quality and the mechanical requirements. Geometrical optimization is typically based on trial-and-error processes, and delays due to the manufacturing of different prototypes increases the development cost of the final product. In this study, the mechanical behavior of a CFRTPs top mount damping component made of polyamide 6 (PA6) reinforced with long glass fibers (47% in volume) and installed in an automobile differential system was evaluated. This was achieved by developing ad hoc tooling for axial testing. The experimental results were used to validate those obtained using a finite element (FE) model based on the fabricated geometry and mechanical properties of the CFRTPs laminate. Furthermore, a complete mathematical procedure was implemented to address the lack of information on the mechanical moduli and Poisson's ratio in the material datasheet for the FE simulation. This method was based on a Halpin-Tsai model and classical lamination theory with a 3D expansion for out-of-plane mechanical property calculation, wherein Tsai's modulus was obtained for checking purposes. The obtained results were fitted with the test results to validate the developed FE model. In addition, this model was used to further optimize the component geometry. The implementation of in silico models based on FE techniques can be useful for accelerating the development of recyclable CFRTPs for large-scale production, allowing significant weight reduction and lower greenhouse emission without diminishing their reliability and safety throughout their useful life.The authors would like to acknowledge the support of CMP Automotive Group for collaboration in the experimental part and to IGESTEK for the information provided on the composites it manufactures
    corecore