Lava flow morphology at an erupting andesitic stratovolcano: a satellite perspective on El Reventador, Ecuador

Lava flows pose a significant hazard to infrastructure and property located close to volcanoes, and understanding how flows advance is necessary to manage volcanic hazard during eruptions. Compared to low-silica basaltic flows, flows of andesite composition are infrequently erupted and so relatively few studies of their characteristics and behaviour exist. We use El Reventador, Ecuador as a target to investigate andesitic lava flow properties during a 4.5 year period of extrusive eruption between February 2012 and August 2016. We use satellite radar to map the dimensions of 43 lava flows and look at variations in their emplacement behaviour over time. We find that flows descend the north and south flanks of El Reventador, and were mostly emplaced during durations shorter than the satellite repeat interval of 24 days.Flows ranged in length from 0.3 to 1.7 km, and the length of these flows decreased over the observation period. We measure a decrease in flow volume with time that is correlated with a long-term exponential decrease in eruption rate, and propose that this behaviour is caused by temporary magma storage in the conduit acting as a melt capacitor between the magma reservoir and the surface. We use the dimensions of the flow levees and widths to estimate the flow yield strengths, which were of the order of 10-100 kPa. We observe that some flows were diverted by topographic obstacles, and compare measurements of decreased channel width and increased flow thickness at the obstacles with observations from laboratory experiments. Radar observations, such as those presented here, could be used to map and measure properties of evolving lava flow fields at other remote or difficult to monitor volcanoes

Wall-Jet Turbulence and Mixing Control by Way of a Pulsed Inlet Velocity

Understanding wall-jet-induced turbulence and mixing is an important challenge in modern engineering, as drag reduction and mixing enhancement are attainable by modifying the flow development. Simulations are performed to investigate the effect on skin friction and flow mixing due to introducing controlled perturbations, at the initial shear layer of a planar wall-jet using jet inlet cyclic pulsing. The billow production by the Kelvin-Helmholtz instability, the instability that drives turbulence in a wall-jet, is modified by the excitation of the inlet velocity profile by a sine wave perturbation. Two types of wall-jet simulations are carried out, a two-dimensional compressible case at Rein = 5000 using the PyFR solver and a three-dimensional incompressible case at Rein = 6000 using the Nek5000 solver. The compressible wall-jet simulation indicates that the addition of a sine wave perturbation of 1% on the inlet velocity, at the initial shear layer, increases the wall-normal turbulence intensity at a Strouhal number (Sr) of 0.05 and reduces the turbulence intensity in all directions at a Sr of 0.25. The incompressible wall-jet simulations show that a perturbation of magnitude 40% of the inlet velocity at a low Sr number of 0.0048 damps turbulence and leads to skin friction reduction. The forced wall-jet experiences a repetitive re-laminarization process that delays transition as well as separation from the wall. A qualitative parametric analysis of the perturbation of the global behavior of the flow development on a plane wall-jet under forced velocity profiles is also presented. Cases at Sr = 0.0048 experience a reduction in the number of turbulent structures while becoming more stable, indicating potential drag reduction. Cases at Sr = 0.02 experience a frequent energy re-supply from the inlet that helps maintain large turbulent structures at further downstream locations, useful for mixing related applications

Characterization of the Japanese Management Technique 5S. Polytechnic Dining Room Case

This research aimed to characterize the Japanese 5S management technique, using a case study of the Polytechnic Dining Room, given that in this unit you can apply the 5S technique without any problem, and improve quality, productivity and competitiveness. Several elements were examined including the existence of work material, procedures for eliminating unnecessary materials, location of work materials, cleaning of work areas, standardization of processes, use of uniforms, and protective equipment, among others. Qualitative and quantitative approaches were used. A documentary research instrument was applied, using a Likert scale with ordinal variables. According to the results, those that obtained the highest rating of 7 were as follows: Seiris (classification) 25%, Seiton (Order) 36%, Seiso (Cleaning) 32%, Seiketsu (Standardization) 36%, and Shitsuke (Maintenance) 57%. Therefore, we conclude that in Shitsuke there was greater employee commitment, and Seiri obtained the lowest qualification. Keywords: 5S, quality improvement, productivity, competitiveness. Resumen Con la finalidad de conocer los elementos innecesarios, existencia de material de trabajo, procedimientos de eliminación de materiales innecesarios, ubicación de materiales de trabajo, limpieza de áreas de trabajo, estandarización de procesos, utilización de uniformes, equipo de protección entre otros, la presente investigación tienen el objetivo de caracterizar la técnica de gestión japonesa 5S, caso Comedor Politécnico, considerando que en esta dependencia puede aplicar sin ninguna problema la técnica 5S, mejorar la calidad, su productividad y competitividad; la investigación tiene un enfoque cualicuantitativo, con un método analítico sintético con un nivel de investigación exploratorio, descriptivo, se aplica un instrumento de investigación documental, de escala con variables ordinales, utilizando la escala Likert, método inductivo empírico de información primaria, en la cual se obtiene la siguientes conclusiones obteniendo la calificación más alta de 7, en lo referente Seiri (clasificación) 25%, Seiton ( Orden)36%, Seiso (Limpieza) 32%, Seiketsu (Estandarización) 36%, Shitsuke ( Mantenimiento) 57%, de esta manera de concluye que en Shitsuke donde existe mayor compromiso de los empleados, y en Seiri es la que menor calificación se obtiene. Palabras clave: 5S, mejora de la calidad, productividad, competitividad

The Liquefaction of Sand Lenses Due to Cyclic Loading

Many studies have been conducted on the effects of cyclic loading on homogeneous saturated deposits of sand, and to a lesser extent on silt and clay. In contrast, very little research has been performed on the effects of cyclic loading on saturated sand lenses located within clay masses. Sand lenses and thin discontinuous layers of loose sand are frequently encountered in saturated clay or silt deposits located in areas of the United States prone to earthquakes. Sand lenses are also frequently associated with hydraulic fill structures, which are known to perform poorly during earthquake loading. The liquefaction and failure of sand lenses has been identified as a major factor in the Turnagain Heights Landslide during the 1964 Alaska Earthquake and lateral spreading landslides in the 1906 San Francisco Earthquake, among others. A major obstacle to laboratory testing of sand lenses is the modeling of a sand lens or lenses within a clay deposit or block, and finding equipment that can subject the sample to cyclic loading. Until now, only theoretical analyses of sand lens failure have been performed, with the most promising method utilizing the principles of Linear Elastic Fracture Mechanics (LEFM) theory. This study developed a method of constructing one or more sand lenses within a block of clay and then applying a uniform cyclic loading with a shaking table. For clay blocks with a single sand lens and with two sand lenses, behavior was closely monitored during the cyclic loading to the point of failure. The results of the testing verified that the principles of the LEFM theory can be used to determine the mode of failure of a sand lens or lenses due to cyclic loading

Economic and Financial Situation of Furniture Removal Services (H4923.04) and Bridge and Viaduct Construction (F4210.32) Enterprises

The primary objective of this investigative work was to determine among the ISICs analyzed – the furniture removal services (H4923.04) and construction of bridges and viaducts (F4210.32), both of which maintain good operation and management – the ISIC that has better economic operation than the other. Bibliographic materials and calculations were studied, and a quantitative approach based on a deductive scheme was applied. Data were analyzed using the Microsoft Excel sheet. It was found that Ciiu 1: H4923.04 – FURNITURE MOVING SERVICES – has had a better economic standing in its operation compared to Ciiu 2 F4210.32 – CONSTRUCTION OF BRIDGES AND VIADUCTS – that presents values at 0 in its financial ratios, that is to say, its financial performance is not positive. The means obtained from each financial ratio were analyzed together with the coefficient of variation which showed that the data tend to be more dispersed in Ciiu 1: H4923.04 – FURNITURE MOVING SERVICES – since Ciiu 2 did not present data. Therefore, to conclude, it was possible to obtain the means of each of the ISICs in question in order to obtain a comparison between the two and to know the benefits they have obtained in the years 2018 and 2019. Keywords: ciiu, financial analysis, means, variation coefficient. Resumen El presente trabajo investigativo tuvo como objetivo principal determinar entre los CIIU analizados servicios de mudanzas de muebles (H4923.04) y construcción de puentes y viaductos (F4210.32) cual ha tenido una buena situación económica en su ejercicio con el fin de determinar que CIIU ha tenido mejores operaciones en su ejercicio, se utilizó para el desarrollo del trabajo materiales bibliográficos y materiales de calculo que nos sirvieron para realizar el estudio respectivo, el método de enfoque aplicado a esta investigación es cuantitativo, el método se basa en un esquema deductivo y lógico, después de haber tenido el marco metodológico se pasó al análisis de resultados realizados en Excel y obtuvimos que el Ciiu 1 :H4923.04 - SERVICIOS DE MUDANZAS DE MUEBLES ha tenido una mejor situación económica en su ejercicio en comparación al Ciiu 2 F4210.32 - CONSTRUCCIÓN DE PUENTES Y VIADUCTOS que presenta valores en 0 en sus ratios financieros es decir que su desenvolvimiento financiero no es positivo, en la discusión se analizaron las medias obtenidas de cada ratio financiero junto con el coeficiente de variación y nos mostró que los datos tienden a ser más dispersos en el Ciiu 1: H4923.04 - SERVICIOS DE MUDANZAS DE MUEBLES ya que en el ciiu 2 no presentan datos, como conclusión obtuvimos que se pudo llegar a conseguir las medias de cada uno de los CIIU en cuestión para así poder obtener una comparación entre ambos y conocer cuáles son los beneficios que han obtenido en los años 2018 y 2019. Palabras Clave: ciiu, análisis financiero, medias, coeficiente de variació

Financial Obligations of Dance Schools and Academies in Ecuador During the Period 2018–2019

This research aims at knowing the financial situation of the Ecuadorian dance schools and academies during the period 2018–2019. A descriptive and quantitative sectional study of the economic documents with the Id 3.1.1 of the population was carried out in the studied schools and academies. The respective documents that were needed for the analysis of the work were downloaded from the official website of SUPERCIAS. The formulas that were used to obtain their pertinent results and discussions were obtained from [8]. The research work began on December 10, 2020 and ended on December 30 of the same year. Results showed that only company 1 is capable of facing its short-term current liabilities and solving its indebtedness because it has been investing effectively in its assets. It was concluded that in ISIC P8542.03 - SCHOOLS AND ACADEMIES OF DANCE, the company that stands out the most and manages to solve its short-term obligations is the company CENTRO LUDICO ARTISTICO PIRQUETTE CLAP SA because it has a high leverage index. This means that whenever it invests in its assets, it obtains an excellent result, and in effect, it obtains good results in sales values. Keywords: indicators, management, solvency, liquidity, company, asset, data. Resumen Este artículo de investigación surge con el objetivo de conocer la situación financiera de las escuelas y academias de baile del Ecuador en el periodo 2018 al 2019. Se realizó un estudio seccional descriptivo y cuantitativo de los documentos económicos con el Id 3.1.1 de la población de estudio escuelas y academias de baile del Ecuador. Los documentos respectivos que se necesitó para el análisis del artículo se descargaron de la página oficial de la SUPERCIAS. Las fórmulas que se utilizaron para sacar sus pertinentes resultados y discusiones fueron obtenidas de [8]. En los resultados obtenidos, solo la empresa 1 está apta para hacer frente a sus pasivos corrientes a corto plazo y solventar sus endeudamientos debido a que ha estado invirtiendo de una manera efectiva en su activo. Se concluyó que en el CIIU P8542.03 - ESCUELAS Y ACADEMIAS DE BAILE la empresa que más resalta y consigue solventar sus obligaciones a corto plazo es la empresa CENTRO LUDICO ARTISTICO PIRQUETTE CLAP S.A debido a que tiene un índice alto en apalancamiento esto quiere decir que siempre que invierte en su patrimonio obtiene un excelente resultado en su activo, y por efecto obtiene buenos resultados en valores de ventas. Palabras Clave: indicadores, gestión, solvencia, liquidez, empresa, activo, datos

Prospective and Mental Change in Decision-Making in Critical Scenarios of Organizations (Review Article)

We understand from the study of neuroscience that our mind has the power to change according to the social and cultural context in which we operate. The purpose of this research was to present epistemological theory, its importance in influencing decision-making, and strategic approaches from the perspective of complexity and neuroscience. For this, an in-depth bibliographic review was carried out based on the epistemological point of view and critical reading of published articles. The results demonstrated considerations about the presence of multiple philosophical traditions in the scientific process; the role of leadership and neuroscience as the axis of knowledge and their value for decision-making; and how, based on the paradigmatic dialectic, a new mental model and innovative foresight are useful for understanding the structures that require new models of planning for the future where possible and desirable. Thus, we conclude that a change of mentality to a new philosophy of interpretation of reality is important for the complexity of the construction of the future. Keywords: neurosciences, quality, managerial skills, neuroliderazgo. Resumen Desde la neurociencia nuestra mente tiene el poder de cambiar de acuerdo al contexto social y cultural en la que nos desenvolvemos, para ello hay que darle al cerebro la importancia de algo nuevo. El artículo tiene como propósito presentar la teoría epistemológica, y su importancia para formar mentes y pensamientos positivos para la toma de decisiones, y mejorar los enfoques estratégicos desde la perspectiva de la complejidad y la neurociencia; para ello se realizó una revisión bibliográfica a profundidad basados en dos enfoques desde lo epistemológico y la lectura crítica de artículos publicados. Frente a tal escenario, se pretende exponer consideraciones acerca de la presencia de estas tres tradiciones filosóficas en la manera científica argumentado liderazgo y neurociencia como eje del conocimiento y sobre su valor para la toma de decisiones fundamentados en la dialéctica paradigmática hacia un nuevo modelo mental e innovador, la prospectiva es útil para comprender las estructuras que requieren nuevos modelos de planificación del futuro en lo posible y lo deseable. En el nivel académico esta la respuesta a la complejidad para la construcción del futuro, es importante un cambio de mentalidad que este sujeto a una nueva filosofía de interpretación de la realidad. Palabras claves: neurociencias, calidad, habilidades directivas, neuroliderazgo

Selection through female fitness helps to explain the maintenance of male flowers

Andromonoecy, the production of both male and hermaphrodite flowers in the same individual, is a widespread phenomenon that occurs in approximately 4,000 species distributed in 33 families. Hypotheses for the evolution of andromonoecy suggest that the production of intermediate proportions of staminate flowers may be favored by selection acting through female components of fitness. Here we used the andromonoecious herb Solanum carolinense to determine the pattern of selection on the production of staminate flowers. A multivariate analysis of selection indicates that selection through female fitness favors the production of staminate flowers in at least one population. We conclude that this counterintuitive benefit of staminate flowers on female fitness highlights the importance of considering female components of fitness in the evolution of andromonoecy, a reproductive system usually interpreted as a "male" strategy