On the optimaL response of q-vortex

Wingtip vortices represent a hazard for the stability of the following airplane in airport highways. These flows have been usually modeled as swirling jets/wakes, which are known to be highly unstable and susceptible to breakdown at high Reynolds numbers for certain flow conditions, but different to the ones present in real flying airplanes. A very recent study based on Direct Numerical Simulations (DNS) shows that a large variety of helical responses can be excited and amplified when a harmonic inlet forcing is imposed. In this work, the optimal response of q-vortex (both axial vorticity and axial velocity can be modeled by a Gaussian profile) is studied by considering the time-harmonically forced problem with a certain frequency ω. We first reproduce Guo and Sun’s results for the Lamb-Oseen vortex (no axial flow) to validate our numerical code. In the axisymmetric case m = 0, the system response is the largest when the input frequency is null. The axial flow has a weak influence in the response for any axial velocity intensity. We also consider helical perturbations |m| = 1. These perturbations are excited through a resonance mechanism at moderate and large wavelengths as it is shown in Figure 1. In addition, Figure 2 shows that the frequency at which the optimal gain is obtained is not a continuous function of the axial wavenumber k. At smaller wavelengths, large response is excited by steady forcing. Regarding the axial flow, the unstable response is the largest when the axial velocity intensity, 1/q, is near to zero. For perturbations with higher azimuthal wavenumbers |m| > 1, the magnitudes of the response are smaller than those for helical modes. In order to establish an alternative validation, DNS has been carried out by using a pseudospectral Fourier formulation finding a very good agreement.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Interpretable Spectral Variational AutoEncoder (ISVAE) for time series clustering

The best encoding is the one that is interpretable in nature. In this work, we introduce a novel model that incorporates an interpretable bottleneck-termed the Filter Bank (FB)-at the outset of a Variational Autoencoder (VAE). This arrangement compels the VAE to attend on the most informative segments of the input signal, fostering the learning of a novel encoding ${f_0}$ which boasts enhanced interpretability and clusterability over traditional latent spaces. By deliberately constraining the VAE with this FB, we intentionally constrict its capacity to access broad input domain information, promoting the development of an encoding that is discernible, separable, and of reduced dimensionality. The evolutionary learning trajectory of ${f_0}$ further manifests as a dynamic hierarchical tree, offering profound insights into cluster similarities. Additionally, for handling intricate data configurations, we propose a tailored decoder structure that is symmetrically aligned with FB's architecture. Empirical evaluations highlight the superior efficacy of ISVAE, which compares favorably to state-of-the-art results in clustering metrics across real-world datasets

Diferencias entre discursos colectivos (verbales) e individuales (escritos) al hacer demostraciones en geometría: una explicación a partir del sistema de normas

Con el fin de involucrar a estudiantes de secundaria en un curso de geometría plana centrado en la práctica de demostrar, fue replicada una innovación que se ha venido desarrollando en un curso de nivel universitario y cuyos efectos han sido interpretados como exitosos. Uno de los resultados de dicha réplica constituye un hecho no esperado por parte del grupo investigativo y de los profesores del curso que participaron en la experiencia: no existe correspondencia entre las producciones verbales de los alumnos –cuando se involucran en la construcción colectiva de la demostración de una conjetura formulada por la clase producto de la solución de un problema– y las producciones autónomas que realizan al reportar por escrito la demostración previamente construida de manera colectiva. Esta situación problemática es explicada mediante un dispositivo analítico que articula constructos tales como situaciones instruccionales, contrato didáctico, normas sociomatemáticas y discurso reflexivo, a partir de los cuales se estudia la interacción en el aula y el rol del profesor en ella

Estructura y dinámica de argumentos analógicos, abductivos y deductivos: un curso de geometría del espacio como contexto de reflexión

Se describen procesos de argumentación con énfasis en los argumentos analógicos, surgidos cuando un grupo de estudiantes aborda un problema que puede ser resuelto tanto en la geometría plana como en la del espacio. Para ello, en el marco de una metodología cualitativa basada en la realidad del aula, se emplea el modelo de Toulmin para tipificar los argumentos producidos y se realiza un análisis ontosemiótico para describir la actividad matemática asociada. Los resultados permiten legitimar el uso de argumentos abductivos o analógicos en procesos de resolución de problemas (particularmente, de geometría del espacio) precisando la forma en que estos articulan y dinamizan diversos objetos (conceptos, procedimientos, proposiciones) presentes en el proceso. Además, permiten detallar las fases de una argumentación por analogía mediante las configuraciones de los dominios que involucra

Subcellular sorting of neuregulins controls the assembly of excitatory-inhibitory cortical circuits

The assembly of specific neuronal circuits relies on the expression of complementary molecular programs in presynaptic and postsynaptic neurons. In the cerebral cortex, the tyrosine kinase receptor ErbB4 is critical for the wiring of specific populations of GABAergic interneurons, in which it paradoxically regulates both the formation of inhibitory synapses as well as the development of excitatory synapses received by these cells. Here, we found that Nrg1 and Nrg3, two members of the neuregulin family of trophic factors, regulate the inhibitory outputs and excitatory inputs of interneurons in the mouse cerebral cortex, respectively. The differential role of Nrg1 and Nrg3 in this process is not due to their receptor-binding EGF-like domain, but rather to their distinctive subcellular localization within pyramidal cells. Our study reveals a novel strategy for the assembly of cortical circuits that involves the differential subcellular sorting of family-related synaptic proteins.Supported by grants from the Medical Research Council (MRC Programme Grant, MR/S010785/1) and European Union’s Horizon 2020 research and innovation programme under grant agreement (AIMS-2-TRIALS, 777394) to BR and OM, and Fondation Roger de Spoelberch to OM. DE-A was supported by a ‘la Caixa’ Foundation Graduate Fellowship

Actividad física y su relación con el sobrepeso y obesidad en docentes de la Universidad Nacional del Altiplano Puno 2017

The practice of physical activity today is necessary because of the multiple benefits it provides to the body. Teachers at the National University of the Altiplano for their different responsibilities and poor practice in healthy lifestyles are likely to develop overweight and obesity. The objective of the research was to know the level of physical activity and its relationship with overweight and obesity in teachers. The research used the scientific method, the type of research is basic, with a descriptive correlational design with a population of 950 teachers and a non-probabilistic sample of 316 teachers (178 men and 138 women), with an average age of 47.48 ± 9,92, the technique used was the observation and the instrument used the physical activity questionnaire and the application of anthropometric measurements (height and weight). Results 76.65% of teachers have a moderate level of physical activity, 63% low and 52.63% high; Likewise, 68.02% are located on the overweight scale, 42.86% with obesity and 12.50% normal, in the sex variable 62.32% of women are on the overweight scale, 76.40% of men on the overweight scale. In conclusion, there is a higher prevalence of overweight and obesity in male teachers, compared to women. It is necessary to implement comprehensive health intervention programs in teachers based on the practice of physical activity and healthy eating.La práctica de la actividad física en la actualidad se hace necesaria por los múltiples beneficios que brinda al organismo. Los docentes de la Universidad Nacional del Altiplano por sus diferentes responsabilidades y escasa práctica en estilos de vida saludables son propensos a desarrollar el sobrepeso y la obesidad. El objetivo de la investigación fue conocer el nivel de actividad física y su relación con el sobrepeso y obesidad en docentes. La investigación utilizó el método científico, el tipo de investigación es básica, con diseño descriptivo correlacional con una población de 950 docentes y con una muestra de tipo no probabilística de 316 docentes (178 varones y 138 mujeres), con promedio de edad de 47.48 ± 9,92, la técnica utilizada fue la observación y el instrumento utilizado el cuestionario de actividad física y la aplicación de las mediciones antropométricas (estatura y peso). Resultados el 76.65% de docentes tienen un nivel de actividad física moderado, el 63% bajo y el 52.63% alto; así mismo el 68.02% se ubican en la escala sobrepeso, el 42.86% con obesidad y el 12.50% normal, en la variable sexo el 62.32% de mujeres se ubican en la escala sobrepeso, el 76.40% de varones en la escala sobrepeso. En conclusión, existe mayor prevalencia de sobrepeso y obesidad en docentes varones, en comparación con las mujeres. Se hace necesario implementar programas de intervención de salud integral en los docentes con base a la práctica de actividad física y alimentación saludable

Mejoramiento De La Productividad En Una Industria Maderera Usando Incentivo Remunerativo

Se estudió el efecto en la productividad de la elaboración de blanks a partir de la implementación de un modelo de incentivo salarial del tipo Improshare, dirigido al personal de una empresa chilena de remanufacturado de maderera que produce molduras y marcos de puerta (ayudante, operador medio y operador máster), para lo cual se compararon dos periodos de tiempo, antes (19 meses) y después (21 meses) de la implementación de la política de incentivo. Los resultados mostraron diferencias estadísticamente significativas en la productividad lograda entre periodos que superó el 10%. Se midió el beneficio promedio de la remuneración de los trabajadores, que llegó a más del 10% y el ahorro de la empresa llegó al 4,6% de la unidad monetaria definida, sin que se haya visto afectada la tasa de accidentabilidad. Lo anterior refuerza lo señalado por diferentes autores que concuerdan que este tipo de herramientas contribuye a mejorar la productividad del proceso e incrementar el salario del trabajador. Su implementación como política salarial en la industria maderera, aporta significativamente a los desafíos de una organización por mantenerse competitiva, así como mejorar la remuneración del trabajador en base a una relación de beneficio mutuo con la empresa. AbstractWe studied the effect on productivity resulting in the blanks elaboration from the implementation of a salary incentive model of Improshare type for staff working group in a sawnwood mill company producer remanufacturing moldings and door frames (assistant, operator and operator master), for which two time periods were compared, before (19 months) and after (21 months) of incentive policy implementation. The results show statistically significant differences in the productivity between periods, of more than 10%. The average benefit of the workers compensation was measured, it reached more than 10% and the savings to the company reached 4,6% of defined monetary unit, without affecting the accident rate. This reinforces the point made by different authors that this kind of tool improves the productivity of the process and increases wages. Its implementation as compensation policy in the lumber industry contributes significantly to the challenges that an organization faces to remain competitive and improve workers compensation based on a mutually beneficial relationship with the company

The role of recent (1985-2014) patterns of land abandonment and environmental factors in the establishment and growth of secondary forests in the Iberian Peninsula

Farmland abandonment has been a widespread land-use change in the Iberian Peninsula since the second half of the 20th century, leading to the establishment of secondary forests across the region. In this study, we aimed to address changes in the recent (1985-2014) emergence patterns of these forests and examine how environmental factors affected their growth by considering differences in leaf-habit types. We used a combination of Landsat-derived land-cover maps and above-ground biomass (AGB) maps from the European Space Agency to assess the secondary forest establishment and growth, respectively, in the study region. We also obtained a set of topographic, climatic and landscape variables from diverse GIS layers and used them for determining changes over time in the environmental drivers of forest establishment and AGB using general linear models. The results highlight that secondary forest cover was still increasing in the Iberian Peninsula at a rate above the European average. Yet, they also indicate a directional change in the emergence of secondary forests towards lower and less steep regions with higher water availability (mean rainfall and SPEI) and less forest cover but are subjected to greater drought events. In addition, these environmental factors differentially affect the growth of forests with different leaf-habit types: i.e., needleleaf secondary forests being less favoured by high temperature and precipitation, and broad-leaf deciduous forests being most negatively affected by drought. Finally, these spatial patterns of forest emergence and the contrasting responses of forest leaf-habits to environmental factors explained the major development of broadleaf evergreen compared to broadleaf deciduous forests and, especially, needleleaf secondary forests. These results will improve the knowledge of forest dynamics that have occurred in the Iberian Peninsula in recent decades and provide an essential tool for understanding the potential effects of climate warming on secondary forest growth

The role of recent (1985-2014) patterns of land abandonment and environmental factors in the establishment and growth of secondary forests in the Iberian Peninsula

Farmland abandonment has been a widespread land-use change in the Iberian Peninsula since the second half of the 20th century, leading to the establishment of secondary forests across the region. In this study, we aimed to address changes in the recent (1985-2014) emergence patterns of these forests and examine how environmental factors affected their growth by considering differences in leaf-habit types. We used a combination of Landsat-derived land-cover maps and above-ground biomass (AGB) maps from the European Space Agency to assess the secondary forest establishment and growth, respectively, in the study region. We also obtained a set of topographic, climatic and landscape variables from diverse GIS layers and used them for determining changes over time in the environmental drivers of forest establishment and AGB using general linear models. The results highlight that secondary forest cover was still increasing in the Iberian Peninsula at a rate above the European average. Yet, they also indicate a directional change in the emergence of secondary forests towards lower and less steep regions with higher water availability (mean rainfall and SPEI) and less forest cover but are subjected to greater drought events. In addition, these environmental factors differentially affect the growth of forests with different leaf-habit types: i.e., needleleaf secondary forests being less favoured by high temperature and precipitation, and broad-leaf deciduous forests being most negatively affected by drought. Finally, these spatial patterns of forest emergence and the contrasting responses of forest leaf-habits to environmental factors explained the major development of broadleaf evergreen compared to broadleaf deciduous forests and, especially, needleleaf secondary forests. These results will improve the knowledge of forest dynamics that have occurred in the Iberian Peninsula in recent decades and provide an essential tool for understanding the potential effects of climate warming on secondary forest growth

The role of recent (1985-2014) patterns of land abandonment and environmental factors in the establishment and growth of secondary forests in the Iberian Peninsula

Farmland abandonment has been a widespread land-use change in the Iberian Peninsula since the second half of the 20th century, leading to the establishment of secondary forests across the region. In this study, we aimed to address changes in the recent (1985-2014) emergence patterns of these forests and examine how environmental factors affected their growth by considering differences in leaf-habit types. We used a combination of Landsat-derived land-cover maps and above-ground biomass (AGB) maps from the European Space Agency to assess the secondary forest establishment and growth, respectively, in the study region. We also obtained a set of topographic, climatic and landscape variables from diverse GIS layers and used them for determining changes over time in the environmental drivers of forest establishment and AGB using general linear models. The results highlight that secondary forest cover was still increasing in the Iberian Peninsula at a rate above the European average. Yet, they also indicate a directional change in the emergence of secondary forests towards lower and less steep regions with higher water availability (mean rainfall and SPEI) and less forest cover but are subjected to greater drought events. In addition, these environmental factors differentially affect the growth of forests with different leaf-habit types: i.e., needleleaf secondary forests being less favoured by high temperature and precipitation, and broad-leaf deciduous forests being most negatively affected by drought. Finally, these spatial patterns of forest emergence and the contrasting responses of forest leaf-habits to environmental factors explained the major development of broadleaf evergreen compared to broadleaf deciduous forests and, especially, needleleaf secondary forests. These results will improve the knowledge of forest dynamics that have occurred in the Iberian Peninsula in recent decades and provide an essential tool for understanding the potential effects of climate warming on secondary forest growth