scholarly journals LOS HERMOSOS TONOS ROJIZOS DE LOS ATARDECERES

Kuxulkab ◽  
2018 ◽  
Vol 24 (49) ◽  
pp. 37
Author(s):  
Lilia María Gama Campillo ◽  
Eduardo Javier Moguel Ordóñez
Keyword(s):  
Rayleigh Scattering ◽  
El Paso ◽  
Visible Spectrum ◽  
Mie Scattering ◽  
Palabras Clave

Las tonalidades rojo-naranja, que observamos en el cielo al alba o en el ocaso, son fenómenos que de forma natural se presentan en la atmósfera y que las culturas ancestrales han podido asociar con mucho éxito a la ocurrencia de otros fenómenos meteorológicos. En la actualidad toda persona que disfruta al alba u ocaso de este fenómeno óptico, puede explicárselo conociendo un poco la composición de la atmósfera y los fenómenos de dispersión de Rayleigh y Efecto o Difusión de Mie Scatter. Sin embargo, dada la creciente actividad productiva del hombre y las emisiones a la atmósfera, es importante reconocer que los gases y partículas emitidas pueden modificar las propiedades ópticas del aire, originando o intensificando los tonos rojizos al amanecer o atardecer, e incluso obstruir casi por completo el paso de la luz solar y solo veríamos colores grisáceos en el cielo. Palabras clave: Contaminación; Dispersión de Rayleigh; Difusión de Mie; espectro visible. Keywords: Pollution; Rayleigh scattering; Mie scattering; Visible spectrum.

scholarly journals MESTRES DA REPORTAGEM: o livro que virou série em favor de estudantes e da sociedade

2019 ◽  
Vol 5 (4) ◽  
pp. 223-236
Author(s):  
Patrícia Sheila Monteiro Paixão Marcos
Keyword(s):  
Daily Life ◽  
El Paso ◽  
Sao Paulo ◽  
Educational Institutions ◽  
São Paulo ◽  
Book Series ◽  
Palabras Clave ◽  
Journalism Students

O artigo apresenta a trajetória da série “Mestres da Reportagem”, produzida por estudantes de Jornalismo de diferentes instituições de ensino do Brasil e jornalistas recém-formados. O projeto começou com um livro, lançado em 2012, vinculado a uma das disciplinas do curso de Jornalismo da extinta Faculdade do Povo, em São Paulo (FAPSP). Em 2015, a obra foi transformada em série, ampliando o leque de coautores. Os volumes da série trazem entrevistas com grandes nomes da reportagem brasileira, proporcionando à sociedade conhecer os bastidores de matérias emblemáticas, que ajudaram a transformar seu cotidiano e a revelar importantes personagens.   PALAVRAS-CHAVE: Mestres da reportagem; Jornalismo; reportagem; livro; série.      ABSTRACT The article reveals the trajectory of the series "Mestres da Reportagem", produced by journalism students from different educational institutions of Brazil and by newly graduated journalists. The project began with a book, launched in 2012, linked to one of the disciplines of the journalism course of the extinct Faculdade do Povo, in São Paulo (FAPSP). In 2015, the work was transformed into a series, expanding the range of co-authors. The volumes of the series bring interviews with big names of the brazilian journalism, providing society to know the backstage of emblematic reports, which helped transform their daily life and reveal important characters.   KEYWORDS: Mestres da reportagem; journalism; report; book; series.     RESUMEN El artículo revela la trayectoria de la serie "Mestres da Reportagem", producida por estudiantes de periodismo de diferentes instituciones educativas del Brasil y periodistas recién graduados. El proyecto comenzó con un libro, lanzado en 2012, vinculado a una de las disciplinas del curso de periodismo de la extinto Faculdade do Povo, en São Paulo (FAPSP). En 2015, el trabajo se transformó en una serie, ampliando la gama de co-autores. Los volúmenes de la serie traen entrevistas con grandes nombres del periodismo brasileño, proporcionando a la sociedad conocer el paso a paso de reportajes emblemáticas, que ayudó a transformar su vida cotidiana y revelar personajes importantes.   PALABRAS CLAVE: Mestres da reportagem; periodismo; reportaje; libro; serie.

scholarly journals Metodologías activas para el aprendizaje del instrumento de medición-micrómetro

2018 ◽  
Vol 3 (10.1) ◽  
pp. 1-16
Author(s):  
Darwin Gregorio Chele Sancan ◽  
Edgar Gustavo Vera Puebla
Keyword(s):  
El Paso ◽  
Palabras Clave ◽  
El Sistema

El presente estudio tiene como objetivo promover el uso de metodologías activas para el aprendizaje del instrumento de medición directa, micrómetro, a la vez que se aplica su principio de funcionamiento, tornillo-tuerca. Lo descrito en este trabajo puede ser empleado para el sistema métrico y el sistema inglés de unidades (0,01 mm y 0,001 pulgadas respectivamente), por medio de la ampliación de las escalas de graduación (las cuales estarán limitadas de acuerdo con el paso del elemento roscado que se utilice) tanto de la escala principal, grabadas en el cilindro exterior como la de la escala vernier, grabada en el tambor, cuya ampliación de las graduaciones dependerá del diámetro en la zona donde se las realice. También se realizó una breve introducción sobre Metrología, sistemas de medición y unidades de medida, así como del instrumento de medición utilizado en el presente estudio, además se expone una propuesta de cómo obtener la apreciación o resolución del instrumento de medición. Para alcanzar la validez de este estudio, y obtener un aprendizaje significativo y duradero, se empleó las siguientes metodologías activas de aprendizaje: el trabajo cooperativo, donde los estudiantes trabajan en conjunto para lograr un objetivo común y son responsables todos los que conforman el grupo, de que puedan aprender unos de otro, a la vez que desarrollan aptitudes propias de trabajo en grupo; el aprendizaje basado en problemas, donde se busca que el estudiante construya su conocimiento sobre problemas y casos de la vida real y el aprendizaje basado en proyectos, donde el estudiante desde sus inicios se enfrente a un aprendizaje activo por medio de proyectos de ingeniería simples, metodologías que permiten que el estudiante participe de manera activa y sea motivado en su proceso de formación como futuro profesional en ingeniería mediante una planificación adecuada de las actividades lúdicas en clases, guiados por el docente, con materiales significativos y conceptualmente de fácil comprensión. Para concretar el estudio, se procede a elaborar un proyecto de aplicación, el cual consiste en la elaboración de un elemento que represente la escala principal y la escala Vernier de un micrómetro en madera con sus respectivas graduaciones. Palabras clave: Aprendizaje; metodologías; metrología; micrómetro; sistema de unidades.

The Polarization Properties Research of Atmospheric Based on Actual Weather Conditions

2014 ◽  
Vol 556-562 ◽  
pp. 933-936
Author(s):  
Fei Zhang ◽  
Xiao Ping Du ◽  
Shen Wang
Keyword(s):  
Rayleigh Scattering ◽  
Weather Conditions ◽  
Mie Scattering ◽  
New Method ◽  
Degree Of Polarization ◽  
Scattering Angle ◽  
Polarization Characteristics ◽  
Simulation Results

A new method to calculate the polarization properties of the atmosphere by combining the Rayleigh scattering and Mie scattering is proposed in this paper. We inversed the values of the required data by experiment and simulated of the atmosphere polarization characteristics under the same conditions. The simulation results show that the proposed method can accurately describe the variation of the atmosphere polarization properties. Besides, the results show such variation: in the same weather conditions, the degree of polarization is gradually increased while scattering angle is gradually increased as 90°; in the same detect conditions, the degree of polarization decreases with the deteriorating weather conditions.

Design and Compiling of Laser Propagation Simulation Software in Atmospheric Environment

2012 ◽  
Vol 490-495 ◽  
pp. 2136-2140
Author(s):  
Tong Gang Zhao ◽  
Zhi Qiang Zhang
Keyword(s):  
Theoretical Model ◽  
Rayleigh Scattering ◽  
Hot Spot ◽  
Theoretical Models ◽  
Mie Scattering ◽  
Simulation System ◽  
Simulation Software ◽  
Atmospheric Environment ◽  
Laser Propagation ◽  
Atmospheric Propagation

As development of laser technology, the characteristic of laser atmospheric propagation is always hot spot in laser domain. Using theoretical models of laser atmospheric propagation, a simulation system is researched by implementing a scientific method of software development. This simulation system can simulate the radiate property of laser propagation in atmosphere, and demonstrate the course of laser propagation. This theoretical model of atmospheric propagation is based on Lambert-Beer law, combined with other classic theoretical model such as Rayleigh scattering and Mie scattering. Multiple scattering theories are used when simulating the laser propagation in smoke or fog. In calculation, the atmosphere is divided into layer. An appropriate model will be selected for calculation in each layer in order to enhance the stimulation precision. Lastly, the figure of light spot is drawn along with transmission space. Laser atmospheric propagation is demonstrated.

Radiative Properties for Fire Suppression Environments Using a Correlated-k Method

2005 ◽  
Author(s):  
William F. Godoy ◽  
Paul E. DesJardin
Keyword(s):  
Rayleigh Scattering ◽  
Fire Suppression ◽  
Mie Scattering ◽  
Distribution Functions ◽  
Radiative Properties ◽  
Cumulative Distribution ◽  
Participating Media ◽  
Property Evaluation ◽  
Highly Sensitive ◽  
Mie Scattering Theory

This study uses the correlated-k (c-k) and Mie scattering theory to evaluate absorption and scattering properties of participating media for fire suppression environments. In this approach the irregular spectral distribution of the radiative properties is reordered into cumulative distribution functions on a narrow band basis increasing the speed of property evaluation when compared to line-by-line calculations. The spectral properties are determined from the HITEMP database for carbon dioxide and water vapor, along with Mie and Rayleigh scattering theories for water droplets and soot particles, respectively. Results are presented for radiative heat transfer in a 1D domain for several mixtures and show that the attenuation of the radiation is highly sensitive to the water droplet size, mass loading and soot particle concentration.

scholarly journals Inter-Particle Effects with a Large Population in Acoustofluidics

Actuators ◽  
2020 ◽  
Vol 9 (4) ◽  
pp. 101
Author(s):  
Kun Jia ◽  
Yulong Wang ◽  
Liqiang Li ◽  
Jian Chen ◽  
Keji Yang
Keyword(s):  
Rayleigh Scattering ◽  
Acoustic Radiation ◽  
Large Population ◽  
Scattering Problem ◽  
Relative Size ◽  
Radiation Force ◽  
Mie Scattering ◽  
Separation Distance ◽  
High Concentration ◽  
Theoretical Understanding

The ultrasonic manipulation of cells and bioparticles in a large population is a maturing technology. There is an unmet demand for improved theoretical understanding of the particle–particle interactions at a high concentration. In this study, a semi-analytical method combining the Jacobi–Anger expansion and two-dimensional finite element solution of the scattering problem is proposed to calculate the acoustic radiation forces acting on massive compressible particles. Acoustic interactions on arrangements of up to several tens of particles are investigated. The particle radius ranges from the Rayleigh scattering limit (ka«1) to the Mie scattering region (ka≈1). The results show that the oscillatory spatial distribution of the secondary radiation force is related to the relative size of co-existing particles, not the absolute value (for particles with the same radius). In addition, the acoustic interaction is non-transmissible for a group of identical particles. For a large number of equidistant particles arranged along a line, the critical separation distance for the attraction force decreases as the number of particles increases, but eventually plateaus (for 16 particles). The range of attraction for the formed cluster is stabilized when the number of aggregated particles reaches a certain value.

Turbid Underwater Polarization Patterns Considering Multiple Mie Scattering of Suspended Particles

2020 ◽  
Vol 86 (12) ◽  
pp. 737-743
Author(s):  
Haoyuan Cheng ◽  
Jinkui Chu ◽  
Ran Zhang ◽  
Lianbiao Tian ◽  
Xinyuan Gui
Keyword(s):  
Rayleigh Scattering ◽  
Field Measurements ◽  
Distribution Patterns ◽  
Suspended Particles ◽  
Mie Scattering ◽  
Polarization Pattern ◽  
Polarization Distribution ◽  
Water Turbidity ◽  
Influence Of Water ◽  
Mie Scattering Theory

It is still unclear how water turbidity affects the underwater polarization pattern. Current simulations only consider single Rayleigh scattering of water molecules and ignore multiple Mie scattering of suspended particles. In this study, a method based on a combination of Monte Carlo numerical simulation and Mie scattering theory is used to establish a model of the turbid underwater polarization distribution. Stokes vector and Mueller matrix are used to simulate the underwater polarization patterns within Snell's window. The distribution patterns and dynamic changes of the simulation are consistent with field measurements. The maximum depth that the polarization pattern can be maintained is calculated for different water types. The influence of water turbidity on polarization patterns is discussed. This model provides a tool for researchers to quantitatively analyze the distribution of turbid underwater polarization. In addition, the study is valuable for remote sensing and marine surveillance.

A Mode-Resolved Continuum Mechanics Model of Acoustic Wave Scattering From Embedded Cylinders

2018 ◽  
Vol 141 (1) ◽  
Author(s):  
Vineet Unni ◽  
Joseph P. Feser
Keyword(s):  
Elastic Wave ◽  
Cross Section ◽  
Continuum Mechanics ◽  
Wave Scattering ◽  
Rayleigh Scattering ◽  
Mie Scattering ◽  
Scattering Cross Section ◽  
Density Contrast ◽  
Continuum Approximation ◽  
Scattering Cross

In this paper, we use continuum mechanics to develop an analytic treatment of elastic wave scattering from an embedded cylinder and show that a classic treatise on the subject contains important errors for oblique angles of incidence, which we correct. We also develop missing equations for the scattering cross section at oblique angles and study the sensitivity of the scattering cross section as a function of elastodynamic contrast mechanisms. We find that in the Mie scattering regime for oblique angles of incidence, both elastic and density contrast are important mechanisms by which scattering can be controlled, but that their effects can offset one another, similar to the theory of reflection at flat interfaces. In comparison, we find that in the Rayleigh scattering regime, elastic and density contrast are always complimentary toward increasing scattering cross section, but for sufficiently high density contrast, the scattering cross section for incident compressional and y-transverse modes is nearly independent of elastic contrast. The solution developed captures the scattering physics for all possible incident elastic wave orientations, polarizations, and wavelengths including the transition from Rayleigh to geometric scattering regimes, so long as the continuum approximation holds. The method could, for example, enable calculation of the thermal conductivity tensor from microscopic principles which requires knowledge of the scattering cross section spanning all possible incident elastic wave orientations and polarizations at thermally excited wavelengths.

scholarly journals Caracterización morfobatimétrica y estimación de sedimentos de la bahía interior de Puno, lago Titicaca, mediante tecnología SIG

2016 ◽  
Vol 18 (2) ◽  
Author(s):  
Alfredo Loza-Del-Carpio ◽  
César Gamarra-Peralta ◽  
Ninfa Condori-Aliaga
Keyword(s):  
Accumulation Rate ◽  
El Paso ◽  
Water Volume ◽  
Gis Technology ◽  
Technology Application ◽  
Sediment Volume ◽  
Palabras Clave ◽  
Lake Morphology ◽  
Sistemas De Informacion ◽  
Bathymetric Changes

<p>Los ecosistemas lénticos, tienden a sufrir cambios morfométricos y batimétricos con el paso del tiempo. Esta condición en la bahía interior de Puno, aún no ha sido detallada, por lo que el presente conllevó a su caracterización en los años 2010 y 2012, para compararla con la del año 1975,  además de estimar el volumen de sedimento acumulado en el lecho lacustre desde esa fecha. Para esto se digitalizaron las cartas batimétricas de 1975 y se hicieron levantamientos actuales mediante el uso de ecosonda y aplicación de tecnologías SIG; luego se trazaron isóbatas y construyeron mapas para comparar las variaciones. La estimación de sedimentos acumulados se realizó por diferencias de volumen de agua y cambios de profundidad entre los años mencionados. Los resultados refieren que las condiciones batimétricas han cambiado relativamente, manteniendo un fondo lacustre irregular, con profundidades máximas de 7.76 m para 1975, 7.07 m para 2010 y 7.19 para el 2012. Sus mayores áreas están ocupadas por profundidades menores a 1 m y los mayores volúmenes en las profundidades de 3 a 4 m. Los perfiles evidencian que la cubeta tiene un talud con mayor profundidad hacia la ciudad de Puno. El área para 1975 fue de 15.79 km<sup>2</sup> y para el 2012 de 15.9 km<sup>2</sup>; para el 2012 el volumen fue de 39 millones de m<sup>3</sup>, menor a 1975 que superó los 42 millones. El volumen de sedimentos acumulado desde 1975 hasta el año 2012 fue de 887352.02 m<sup>3</sup>, siendo la tasa de acumulación de 23982.48 m<sup>3</sup>/año y 4.1 mm/año.</p><p> </p><p><strong>Palabras clave: </strong>Isobatas, morfología lagos, perfiles de profundidad, Sistemas de Información Geográfica.</p><p>                                                    </p><p> </p><p align="center"><strong>Morphobathymetric characterization and sediments estimating of the Puno’s inner bay, Titicaca lake, by GIS technology</strong></p><p align="center"><strong>ABSTRACT</strong></p><p>Lentic ecosystems, suffers morphometric and bathymetric changes in the course of time. This condition at Puno's interior bay, has not yet been detailed, by which this research was orientated to its characterization in the years 2010 and 2012 to compare with 1975, in addition to estimate sediment volume accumulated in the water bed from that date. It digitalized bathymetric charts of 1975 and at present were done new charts by mean ecosound and GIS technology application to compare variations. Sediments accumulates volume was estimated by differences of water volume and in-depth changes between years mentioned. Results refer than bathymetric conditions have changed relatively, keeping an irregular profundity, maximum depths were 7.76 m for 1975, 7.07 m for 2010 and 7.19 by 2012. Largest areas are occupied by lower depths to 1 m and higher volumes in the depths of 3-4 m. Profiles evidence that the bucket has bigger inclination and depth toward Puno's city. 1975 area was 15.79 km<sup>2</sup> and for 2010 and 2012 was 15.9 km<sup>2</sup>; 2012 volume was 39 million m<sup>3</sup>, less than 1975 with more than 42 million. Sediment volume accumulated from 1975 until 2012 was 887352.02 m<sup>3</sup>, and accumulation rate of 23982.48 m<sup>3</sup>/year or 4.1 mm/year.</p><p> </p><p><strong>Key words: </strong>Isobaths, lake morphology, depth profiles, Geographic Information Systems.</p><p> </p>

scholarly journals Coherent Scattering of Ultraviolet Light by Avian Feather Barbs

The Auk ◽  
2003 ◽  
Vol 120 (1) ◽  
pp. 163-170 ◽  
Author(s):  
Richard O. Prum ◽  
Staffan Andersson ◽  
Rodolfo H. Torres
Keyword(s):  
Rayleigh Scattering ◽  
Power Spectra ◽  
Coherent Scattering ◽  
Mie Scattering ◽  
Two Dimensional ◽  
Structural Colors ◽  
Physical Mechanisms ◽  
Spatial Frequencies ◽  
Transmission Electron ◽  
Alternative Hypotheses

Abstract Ultraviolet (UV) structural colors of avian feathers are produced by the spongy medullary keratin of feather barbs, but various physical mechanisms have been hypothesized to produce those colors, including Rayleigh scattering, Mie scattering, and coherent scattering (i.e. constructive interference). We used two-dimensional Fourier analysis of transmission electron micrographs of the medullary keratin of UV-colored feather barbs of the Blue Whistling Thrush (Myiophonus caeruleus) (Turdidae) to test the alternative hypotheses for production of those UV structural hues. The two-dimensional Fourier power spectra of the tissue reveal a ring-like distribution of peak periodicity at intermediate spatial frequencies (∼0.078 nm −1), which documents that Myiophonus medullary keratin is substantially nanostructured and equivalently ordered in all directions. This nanoscale spatial order falsifies a basic assumption of both the Rayleigh scattering and Mie scattering. A predicted reflectance spectrum based on the Fourier power spectra matches hue of the measured reflectance spectra of the feathers (345 nm). These results demonstrate that the Myiophonus medullary keratin is ordered at the appropriately nanoscale to produce the observed UV hues by coherent scattering.

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