bluuebunny/crossref_metadata_2025 huggingface dataset:
Improved tropospheric and stratospheric sulfur cycle in the aerosol-chemistry-climate model SOCOL-AERv2
Authors: Feinberg Aryeh , Sukhodolov Timofei , Luo Bei-Ping , Rozanov Eugene , Winkel Lenny H. E. , Peter Thomas , Stenke Andrea
Published: May 2019

Abstract. SOCOL-AERv1 was developed as an aerosol-chemistry-climate model to study the stratospheric sulfur cycle and its influence on climate and the ozone layer. It includes a sectional aerosol model that tracks the sulfate particle size distribution in 40 size bins, between 0.39 nm to 3.2 µm. Sheng et al. (2015) showed that SOCOL-AERv1 successfully matched observable quantities related to stratospheric aerosol, including a simulated stratospheric aerosol burden of 109 Gg of sulfur (S), very close to the satellite-derived estimate available in 2015, 112 Gg S. In the meantime, both the satellite retrieval and SOCOL-AER have undergone significant improvements. In producing SOCOL-AERv2 we have implemented several updates to the model: adding interactive deposition schemes, improving the sulfate mass and particle number conservation, and expanding the tropospheric chemistry scheme. We compare the two versions of the model with background stratospheric sulfate aerosol observations, stratospheric aerosol evolution after Pinatubo, and ground-based sulfur deposition networks. SOCOL-AERv2 shows similar levels of agreement as SOCOL-AERv1 with satellite-measured extinctions and in situ optical particle counter (OPC) balloon flights. Also, the volcanically quiescent total stratospheric aerosol burden simulated in SOCOL-AERv2, 160 Gg S, agrees very well with the new satellite estimate of 165 Gg S. However, SOCOL-AERv2 simulates too high cross-tropopause transport of tropospheric SO2 and/or sulfate aerosol, leading to an overestimation of lower stratospheric aerosol. Due to the current lack of upper tropospheric SO2 measurements and the neglect of organic aerosol in the model, the lower stratospheric bias of SOCOL-AERv2 was not further improved. Model performance under volcanically perturbed conditions has also undergone some changes, resulting in a slightly lower shorter volcanic aerosol lifetime after the Pinatubo eruption. With the improved deposition schemes of SOCOL-AERv2, simulated sulfur wet deposition fluxes are within a factor of 2 of measured deposition fluxes at 78 % of the measurement stations globally, an agreement which is on par with previous model intercomparison studies. Because of these improvements, SOCOL-AERv2 will be better suited to studying changes to atmospheric sulfur deposition due to variations in climate and emissions.
Wetropolis extreme rainfall and flood demonstrator: from
mathematical design to outreach and research
Authors: Bokhove Onno , Hicks Tiffany , Zweers Wout , Kent Tom
Published: May 2019

Abstract. Wetropolis is a transportable table-top demonstration model with extreme rainfall and flooding events. It is a conceptual model with random rainfall, river flow, a flood plain, an upland reservoir, a porous moor, representing the upper catchment and visualising groundwater flow, and a city which can flood following extreme rainfall. Its aim is to let the viewer experience extreme rainfall and flood events in a physical model on reduced spatial and temporal scales. In addition, it conveys concepts of flood storage and control, via manual intervention. To guide the building of an operational Wetropolis, we have explored its spatial and temporal dimensions first in a simplified mathematical design. We explain this mathematical model in detail since it was a crucial step in Wetropolis' design and it is of scientific interest from a hydrodynamic modelling perspective. The key novelty is the supply of rainfall every Wetropolis day (unit wd), varied temporally and spatially in terms of both the amount of rain and the rainfall location. The joint probabilities (rain amount times rain location) are determined daily as one 10 of 16 possible outcomes from two asymmetric Galton boards, in which steel balls fall down every wd, with the most extreme rainfall event involving 90 % rainfall on both moor and reservoir. This occurs with a probability of circa 3 % and – by design – can cause severe floods in the city. This randomised rainfall has a Wetropolis' return period of 6:06min, short enough to wait for but sufficiently extreme or long to get slightly irritated as a viewer. While Wetropolis should be experienced live, here we provide a photographic overview. To date, Wetropolis has been showcased to over 200 flood victims at workshops and 15 exhibitions on recent UK floods, as well as to flood practitioners and scientists at various workshops. To enhance Wetropolis' reach, we analyse and report here how both the general public and professionals interacted with Wetropolis. We conclude with a discussion on some ongoing design changes, including how people can experience natural flood management in a revised Wetropolis design, before highlighting how the Wetropolis experience can stimulate new approaches in hydrological modelling, flood mitigation and control in science, education and water management.
Reliable reference for the methane concentrations in Lake Kivu at
the beginning of industrial exploitation
Authors: Boehrer Bertram , von Tümpling Wolf , Mugisha Ange , Rogemont Christophe , Umutoni Augusta
Published: May 2019

Abstract. Dissolved methane in Lake Kivu (East Africa) represents a precious energy deposit for the neighbouring countries, but the high gas loads have also been conceived as a threat by the local population. This is especially the case when stratification in the lake is changed during the planned industrial exploitation. Both issues require accurate and reliable measurements of dissolved gases and temporal changes to take responsible action. Previous data fulfilled these requirements only unsatisfactorily. Prior to our measurements, there was considerable disagreement about prognosticated new formation of methane. We show how measurement accuracy could be significantly improved by implementing equipment, which was especially designed and modified for the complex gas conditions in Lake Kivu. From 150 m to 430 m depth, samples were taken to determine the amount of dissolved methane and dissolved carbon dioxide more reliably and more accurately. Beyond the provision of gas concentration profiles at the beginning of exploitation, this investigation should also provide methods to survey the further evolution of gases over time. The use of gas tight sampling bags produced highly reliable and accurate measurements. Our measurements confirmed the huge amount of stored methane, but they do clearly not support the current believe of a significant recharge beyond diffusive loss. Direct measurements with a custom-made gas pressure sensor indicated no imminent endangerment through limnic eruptions. A further survey of gas pressures, however, is mandatory to detect changing conditions. With sampling bags and gas pressure sensor, we introduced reliable and highly accurate measuring approaches for the survey of the further development of gas concentrations. This equipment only requires little effort for calibration, which can also be accomplished in remote areas of Africa.
Sandbag Replacement Systems – Stability, Functionality and
Handling
Authors: Lankenau Lena , Massolle Christopher , Koppe Bäbel , Krull Veronique
Published: May 2019

Abstract. The classic aid in operative flood defence is the sandbag. Over the past few decades, though, so-called sandbag replacement systems (SBRS) have also been available for flood fighting. Although the use of sandbags is time-consuming as well as highly intensive in terms of materials and personnel, so far SBRS are rarely used in Germany. However, owing to their functionality and their labour and time-saving characteristics, they can make an essential contribution to flood protection – and this all the more so in view of the expected consequences of climate change. In order to foster confidence in such systems, the Institute of Hydraulic Engineering at the Hochschule Bremen – City University of Applied Sciences (IWA) carried out a series of systematic tests of SBRS that focused on the functionality, stability and handling of the systems. The experience gained shows that SBRS have the potential to make flood defence more efficient than the use of sandbags alone. Since SBRS are technical systems whose functional capability must be proven before they can be used, it is recommended to introduce an official test and certification procedure.
Toward a coupled model to investigate wave-sea ice interactions in the Arctic marginal ice zone
Authors: Boutin Guillaume , Lique Camille , Ardhuin Fabrice , Rousset Clément , Talandier Claude , Accensi Mickael , Girard-Ardhuin Fanny
Published: May 2019

Abstract. The Arctic Marginal Ice Zone (MIZ), where strong interactions between sea ice, ocean and atmosphere are taking place, is expanding as the result of the on-going sea ice retreat. Yet, state-of-art models are not capturing the complexity of the varied processes occurring in the MIZ, and in particular the processes involved in the ocean-sea ice interactions. In the present study, a coupled sea ice - wave model is developed, in order to improve our understanding and model representation of those interactions. The coupling allows us to account for the wave radiative stress resulting from the wave attenuation by sea ice, and the sea ice lateral melt resulting from the wave-induced sea ice break-up. We found that, locally in the MIZ, the waves can affect the sea ice drift and melt, resulting in significant changes in sea ice concentration and thickness as well as sea surface temperature and salinity. Our results highlight the need to include the wave-sea ice processes in models aiming at forecasting sea ice conditions on short time scale, although the coupling between waves and sea ice would probably required to be investigated in a more complex system, allowing for interactions with the ocean and the atmosphere.
La macroeconomía kaleckiana: ¿una tradición de investigación?
Authors: Cárdenas del Rey Luis
Published: May 2019

En este trabajo se analiza si la macroeconomía kaleckiana puede ser considerada una tradición de pensamiento en el sentido dado por Larry Laudan (1978). Para ello se analiza la evolución del pensamiento teórico, mediante una revisión de la literatura teórica y empírica, partiendo desde la obra de Kalecki hasta los trabajos más recientes, pasando por los estudios de Steindl o Goodwin. Los autores han sido seleccionados por un método agrupador que consiste en identificar puntos comunes, en vez de diferencias. Además, se destacan los principales postulados y conceptos que son mayoritariamente compartidos dentro de esta tradición, y que constituyen un mapa conceptual de la cuestión. A continuación, se repasan y clasifican los estudios empíricos para determinar el objeto y resultados de las investigaciones aplicadas, esencialmente orientadas a establecer los regímenes de crecimiento en la mayoría de países. Ambas cuestiones, teoría y resultados, permiten concluir que se trata de una tradición de investigación en términos epistemológicos.
La primera guerra mundial y la conducta económica del Estado en el pensamiento militar en Argentina
Authors: Avellaneda Aldo
Published: May 2019

Los estudios sobre el pensamiento económico en América Latina no se han detenido en los cuadros militares como actores sociales relevantes a lo largo de casi todo el siglo XX. En este artículo trato de rastrear el surgimiento del interés y la preocupación por el comportamiento económico del Estado en las reflexiones militares. Identifico la Primera Guerra Mundial como una coyuntura crítica que introduce la pregunta por la economía y que viene de la mano de la convicción en el pensamiento militar de que en adelante las guerras serán industriales o no serán. Por medio de un repaso de diversas publicaciones militares —revistas, libros y memorias ministeriales— intento seguir el recorrido de las reflexiones, que parten del interés por la propia potencia militar, pero que rápidamente pasan a considerar la posibilidad y los beneficios de un Estado que apoye una planificación industrial.
The origin of money from the money-debt approach
Authors: Garzón Espinosa Eduardo
Published: May 2019

There are two fundamental approaches to the nature and origin of money that are incompatible with each other: money-commodity and money-debt. The first one has occupied a hegemonic position in the academy —and so outside it— throughout history. On the other hand, the money-debt approach was developed in response to the conventional view, although it currently occupies a marginal place in the academic sphere and is barely known beyond it. Despite its low popularity, the unorthodox outlook of money-debt is much more useful in order to understand the origin and nature of money; and represents a much more accurate analytical framework to monetary phenomena. In this paper a detailed review of the origin of money from this less-known approach is made in order to demonstrate its analytical superiority against the hegemonic approach that suffers from significant theoretical inconsistencies and a lack of empirical support.
An Empirical Study on Career Choices Among Undergraduates: A PLS-SEM Hierarchical Component Model (HCM) Approach
Authors: Wong Siew Chin , Lim Jia Ying , Lim Chui Seong , Hong Kay Tze
Published: May 2019

This study examines how undergraduates’ personality, parental and peer influences on their career choice. Partial Least Square, hierarchical component model (HCM) was used to measure the formative measurement model of personality construct and reflective measurement models of parent and peer influence constructs on career choices in the study. Data were collected from 218 of undergraduates from local private and public universities. Findings show that there are significant positive relationship between personality, parental and peer influences and career choices. Such insights are useful for HRD practitioners to develop relevant HRD interventions to assist individuals and organizations in career development. Limitations and suggestions for future research are also discussed.
Algunos consideraciones en torno al recurso agua en El Salvador
Authors: Badía Serra Eduardo
Published: May 2019

No es el objeto de este trabajo hacer una relación pormenorizada y detallada del recurso agua en el país.Tampoco se enfoca dicho recurso desde una completa, estricta y rigurosa visión técnica. Más bien, su sólo fin es proporcionar un panorama global de la situación, que sea comprensible al común de la población, y que permita ira sensibilizarnos ante la gravedad del problema.El Salvador se encuentra en una situación realmente crítica con relación a la disponibilidad y uso del agua. A ello se suma una escasa intención gubernamental en cuanto a preservar sus fuentes y racionalizar su uso.Y también la muy precaria capacidad técnica de los entes involucrados en ello para encontrar mejores alternativas de explotación, distribución y comercialización.
La función punitiva del derecho penal
Authors: Trejo Escobar Miguel Alberto
Published: May 2019

Estas breves líneas se refieren al análisis de la función punitiva del Derecho Penal, la cual aparece vinculada y depende de la función que se le asigne a las principales consecuencias jurídicas del hecho punible: penas Art. 44 CP y medidas de seguridad Art. 93 CP, medios más característicos de la intervención punitiva estatal; pero, el análisis es parcial, pues está limitado únicamente al examen de los aspectos básicos de la pena, tales como: el concepto, origen, justificación, naturaleza, sentidos, todo ello en concordancia con lo regulado en nuestro Ordenamiento Jurídico.El tema se caracteriza por una teorización de los puntos de vista filosóficos que consideran al Derecho Penal como un instrumento al servicio del valor justicia frente a los que lo entienden como un instrumento que debe servir prioritariamente al valor utilidad.
¿Ha entrado por fin El Salvador en una fase de alto crecimiento económico?
Authors: Acevedo Carlos
Published: May 2019

Ciertamente, la dinámica económica reciente contrasta con la desaceleración que la economía salvadoreña había venido mostrando desde mediados de los noventa y, particularmente, con la tasa de crecimiento promedio anual de 2% registrada durante 2000-2005.La pregunta obligada que surge frente a este fenómeno es si se trata simplemente de una fase pasajera del ciclo de negocios o si el mismo efectivamente refleja el posicionamiento del país en una trayectoria sostenida de alto crecimiento en el largo plazo.
Editorial No. 40
Authors: Editor El
Published: May 2019

Revista Entorno N°40 (2008)
Integración al centro histórico de San Salvador de los edificios contemporáneos de la Universidad Tecnológica
Authors: Porras Pineda José Luis
Published: May 2019

La investigación comienza girando al lector común de cómo los primeros habitantes de Centroamérica y parte de sus obras en urbanismo y arquitectura han dejado rasgos culturales que son importantes tomarlos en cuenta, al igual que los rasgos de la época colonial, para llegar a ubicarnos en el contexto de la problemática planteada por resolver.Así mismo, se explica cómo las fichas de recopilación de datos que se ocuparon en la investigación permitieron a su vez relacionar la sociedad y su cultura en el tiempo y Jugar de una manera general, propiciando y enriqueciendo su respuesta en un ámbito especial.
Se terminaron las recetas
Authors: Loucel José Mauricio
Published: May 2019

Es indudable que el mundo se encuentra en una crisis que seguramente afecta o afectará, tarde o temprano, a todos los pueblos de la Tierra. No podemos prever lo que vendrá a continuación, pero indudablemente todo es el producto de un sistema que se ha contradicho permanentemente en provecho de políticas excluyentes e injustas.Durante muchos años estuvimos sujetos a los consejos que los organismos internacionales nos propusieron e impusieron, con el beneplácito de aquellos para quienes era ventajoso aceptarlos e implantarlos, no importando si los mismos habían sido sujetos a un análisis exhaustivo.
Estamos en el peor y el mejor de los momentos
Authors: Fabián Roberto Rubio
Published: May 2019

Fue la mejor y la peor de las épocas, el siglo de la locura y la razón, de la fe y la incredulidad; fue un período de luz y de tinieblas, de esperanza y desesperación, en el cual se percibía el horizonte más espléndido y la noche más oscura." Así se expresaba Charles Dickens en su novela Historia de dos ciudades (1859).Novela que analiza y compara el momento histórico que vivían las dos grandes ciudades europeas en la época de la Revolución francesa: la aparentemente tranquila y pacífica Londres y la convulsionada y caótica París.Momento del mundo occidental en el que las coordenadas de la historia no eran ni simétricas ni absolutas, sino contradictorias y relativas.
Lineamientos para constituir un despacho de contaduría pública y auditoría
Authors: Melgar Oscar Armando , Moreno Carlos
Published: May 2019

La investigación versa sobre la necesidad de comprender la relevancia que cobra el hecho de conocer los diversos pasos para legalizar la constitución de un despacho de contaduría pública en El Salvador, sea como persona natural o jurídica, conocimiento clave para todo contador público que desee independizarse.Esto es un aspecto que fue demostrable en el trabajo de campo realizado. Además, se hace énfasis en cumplimientos de la normativa técnica como base para brindar un mejor servicio profesional. De igual forma el cumplimiento de la normativa legal y ética, ya que esto le agrega valor al cliente.En el estudio se hace un esbozo histórico para comprender la evolución que ha tenido la contaduría pública en El Salvador, observando cómo la contaduría pública ha evolucionado como una profesión liberal.El producto final es una guía de cumplimiento de obligaciones tributarias, mercantiles, provisionales y técnicas para la constitución de un despacho de contaduría pública y auditoría en El Salvador. En ella se expone con detalles los pasos por seguir y, además, desarrollamos un caso de aplicación práctica.
Percepción en competitividades lingüísticas en idioma inglés, caso deportados de Estados Unidos
Authors: Marroquín Jiménez Wilfredo , Cortez Guillermo
Published: May 2019

El estudio tiene como objetivo general evaluar la percepción de competitividades lingüísticas en el idioma inglés de deportados sin antecedentes penales de los Estados Unidos, en trece cabeceras departamentales, durante el mes de noviembre de 2008.Este se fundamenta en seis niveles de aprendizaje del Marco Común Europeo para las Lenguas, y está siendo adoptado por las instituciones educativas a escala mundial para evaluar el desarrollo de los aprendices de cualquier idioma; en este caso, el idioma inglés.El estudio evaluativo es de carácter deductivo hipotético. El tipo de estudio es de asociación, y se hace uso de técnicas multivariantes. La percepción de las competitividades lingüísticas en el idioma inglés es “bastante representativo” con un coeficiente de variabilidad del 18,81%. Los resultados son favorables.
Actitudes, dominio y uso de tecnologías de información y comunicación TIC
Authors: Orantes Luis Fernando
Published: May 2019

El objetivo del presente artículo es determinar las actitudes, dominio y uso de las Tecnologías de Información y Comunicación en los docentes de las universidades privadas de El Salvador.La muestra fue de 742 docentes, 487 (65,6%) hombres y 255 (34,4%) mujeres. Las variables mencionadas se comparan con el sexo, edad, nivel profesional, tiempo de ejercer la docencia y el tipo de contrato laboral.Los resultados descriptivos reflejaron que un 85% de la muestra tiene actitudes positivas hacia las TIC en educación y un 15% tiene actitudes de desconfianza; en cuanto al dominio, el 82% de la muestra indica las tecnologías como herramienta general y el 63,5% como herramienta en educación; en el uso, el 76,4% la define como herramienta general y el 41,9%, como herramienta en educación.En los resultados inferenciales se reflejó que el sexo, nivel profesional y tipo de contrato laboral no tienen diferencia significativa en ninguna de las variables.La Edad no presenta diferencias significativas en las actitudes, pero sí en el dominio y el uso. Adicionalmente se observa que existe diferencia significativa entre el tiempo de ejercer la docencia con el dominio y uso de las TIC.
Importancia de investigar sobre el pensamiento crítico y su desarrollo en la educación superior
Authors: Velásquez de Suárez Marta Judith , Figueroa Hugo Ernesto , Viera Merey Asunción
Published: May 2019

Desarrollar y difundir conocimiento de alto nivel académico constituye una de las aspiraciones fijadas en la misión de la Universidad Tecnológica de El Salvador; y consecuente con dicho propósito, quiere ser una institución reconocida por la calidad de su educación.Misión y visión engarzadas así en torno al tema de la educación y el conocimiento responden a una de las razones de ser, comúnmente aceptada, de este tipo de instituciones: formar profesionales críticos, de tal manera que puedan contribuir al crecimiento y a los cambios que requiera la sociedad.En sociedades donde la ignorancia y la injusticia van a galope tendido, no cabe duda de que formar personas críticas se vuelve una acción pedagógica de primer orden.Esto implica una constante revisión y transformación de la educación. Muy a menudo se escucha y se lee que una educación que fomenta la adaptación, la memorización y la repetición antes que el ejercicio del pensamiento crítico, más que formar, deforma y se vuelve nociva; sobre todo, porque educa para el consumo, la imitación, la pasividad y la complacencia.Ahora bien, si la mayoría de instituciones educativas pretende efectivamente formar profesionales críticos, resta averiguar, establecer o determinar cómo es que esa aspiración se va materializando o realizando en el proceso enseñanza aprendizaje, y si tales instituciones tienen claro en qué cosiste eso que se da en llamar "pensamiento crítico".
Orientación educativa especializada : orientación a la diversidad. Una oportunidad para la comunidad educativa
Authors: Mayorga Morena Lidia Azucena
Published: May 2019

El presente artículo analiza los fundamentos teóricos de la orientación para la atención a la diversidad y su vinculación posible con un contexto universitario local. Asimismo, hace referencia a su aplicación en otros países, como la experiencia española que ha puesto en práctica el modelo y estrategias para la atención diversificada. Se insiste que todo plan de orientación para la atención de la diversidad solo es posible, si se toman en cuenta las medidas ordinarias y extraordinarias de atención (en niveles primarios, medios y universitarios), aspectos que pueden ser expresados a través del currículo; de lo contrario las instituciones que quieran aplicarlo, no experimentarán los resultados esperados.
Experiencia académica de Licenciatura en Turismo de Universidad Autónoma del Estado de Hidalgo, México
Authors: Muñoz Chávez Juana Patricia , Hernández Ramírez Victoria , Pedraza Elba Mariana
Published: May 2019

Se realiza un análisis de trayectoria escolar a través de indicadores más significativos del programa educativo de la Licenciatura en Turismo de la Universidad Autónoma del Estado de Hidalgo. Se aplica una metodología propuesta por autores como Camarena (1985), Altamira (1997) y González (1998) para el cálculo de los indicadores de eficiencia terminal, eficiencia de egreso, tasa de promoción y tasa de deserción. Los resultados obtenidos reflejaron comportamiento de la trayectoria escolar experimentada en la licenciatura, que permite tomar medidas y estrategias enfocadas a disminuir las deficiencias detectadas.
Análisis de la seguridad pública en el 2010
Authors: Portillo Cuadra René
Published: May 2019

El Plan quinquenal 2010-2014 presentado por el Gobierno del presidente Mauricio Funes, sostiene que, desde el inicio de la posguerra, nuestro país ha registrado elevados niveles de violencia e inseguridad, y por esta razón ha sido considerado uno de los países más violentos de la región; sus tasas de homicidios superaban los 50 homicidios por cada cien mil habitantes. Estas cifras generan inseguridad en la ciudadanía y se convierten en uno de los principales problemas que enfrenta el país. El citado Plan quinquenal señala como principales líneas de acción, en materia de control y represión del delito, las que a continuación se describen: a) Combatir frontalmente la criminalidad en todas sus expresiones y, en especial, los delitos que más afectan a la ciudadanía; b) Reducir la impunidad mediante el fortalecimiento de las instituciones del sector justicia encargadas de la investigación de los hechos delictivos y a través de la mejora de la coordinación interinstitucional; c) Modernizar y profesionalizar la Policía Nacional Civil (PNC) en sus funciones de control y represión (gestión, disuasión, investigación criminal e inteligencia).
Epistemología, complejidad y competencias
Authors: Flores M. José Humberto
Published: May 2019

Para introducir los temas de la teoría del conocimiento, la epistemología, la ciencia, la verdad y la filosofía nos parecen sugerentes las palabras que escribía san Agustín en de Trinitate IX, 1) en el siglo IV de nuestra era: Busquemos como buscan los que aún no han encontrado, y encontremos como encuentran los que aún han de buscar, porque cuando el hombre ha terminado algo no ha hecho sino comenzar.
Redes académicas-científicas y cooperación internacional universitaria
Authors: Orantes Blanca Ruth
Published: May 2019

El mundo ha cambiado. No solo el académico, sino también el contexto, lo cual implica nuevas formas de relacionarse en que se deben unificar esfuerzos colaborativos e integrales.Gracias a la sociedad del conocimiento, que ha permitido a las redes nacer y crecer para bien de las instituciones de educación superior, el individualismo está siendo relegado por nuevas formas de comunicación y vinculación que ofrecen oportunidades de integración a escala nacional, regional e internacional.Las universidades no son ajenas a este fenómeno, y muchas ya hacen esfuerzos por integrarse a las redes académicas en sus distintas modalidades, como una opción para beneficiarse de la cooperación internacional.
Factores de expulsión-atracción y redes familiares, como motivadores de emigración en adolescentes de Metapán. Departamento de Santa Ana, El Salvador
Authors: Orantes Salazar Luis Fernando
Published: May 2019

En el presente artículo se explora la influencia que los factores de expulsión, de atracción y las redes familiares establecidas en Estados Unidos ejercen sobre el fenómeno migratorio de los adolescentes de Metapán. Pretende, asimismo, determinar la influencia de los factores sexo, nivel de inglés e ingresos familiares sobre el proceso de emigración. Para su materialización se realizó un estudio en 290 estudiantes de 9º grado de los centros escolares de la ciudad de Metapán, utilizando un muestreo probabilístico mediante encuesta. Los resultados encontrados concluyen que la mayor influencia en el deseo de emigrar son los factores de expulsión, especialmente el alto índice de delincuencia, las pocas probabilidades laborales y el costo de vida de El Salvador. Los factores de atracción presentaron resultados con menor influencia que los factores de expulsión en el deseo de emigrar, observándose que el aspecto económico y salarial son los atractivos más relevantes de Estados Unidos; y las redes familiares facilitan el proceso y reducen costos básicos de emigración. La variable sexo fue la única que presentó diferencias significativas en el deseo de emigrar y las variables nivel de inglés y nivel de ingresos familiares no tuvieron diferencias significativas en el deseo de emigrar.
Editorial No. 52
Authors: Editor El
Published: May 2019

Entorno, abril 2013, número 52: 5
Estructuras de planta circular prehispánicas en El Salvador
Authors: Morán Carmen Margarita
Published: May 2019

Algunos estudiosos de la cultura mesoamericana se refieren a las estructuras circulares y/o de planta circular de dicha región como anómalas, vinculándolas erróneamente al uso ceremonial relacionado con la deidad Quetzalcoatl; otra equivocación que usualmente se comete, es manifestar que este tipo de estructuras, casi inalterablemente, va a obedecer a la filiación tolteca o mexicana; asimismo son consideradas como indiscutibles marcadoras del período posclásico (9001525 d.C.). Ahora bien, partiendo de lo anterior, se realizó una investigación bibliográfica documental que permitió recolectar la mayor cantidad de datos posibles acerca de las estructuras de planta circular prehispánicas que hasta la fecha se han registrado en territorio salvadoreño, información con las cual se logró desmitificar las afirmaciones expuestas.
Socially-shared Metacognitive Regulation Episodes Between Undergraduate Engineering Students During a Collaborative Genre Analysis Task in an English for Academic Purposes Course
Authors: Seiradakis Emmanouela , Spantidakis Ιoannis
Published: May 2019

Recent findings suggest that genre-based tasks such as move analysis when underpinned by the theory of metacognition can familiarize undergraduate students with newly encountered academic genres such as the research article. However, there still is a limited understanding about how and when novices engage in socially shared metacognitive regulation processes (SSMR) during online collaborative genre analysis tasks. The purpose of this study was to identify when and how a small group of undergraduate engineering students engaged in SSMR processes during a collaborative online move analysis wiki task. Results suggest SSMR was frequently triggered when participants faced a task-related problem and manifested as an expression of doubt and conflicting ideas or when participants attempted to reach a consensus on seemingly difficult genre analysis aspects.
Ants’ Capability of Adding Numbers of Identical Elements
Authors: Cammaerts Marie-Claire , Cammaerts Roger
Published: May 2019

Knowing that the workers of the ant Myrmica sabuleti can distinguish different numbers of elements and have a basic notion of zero, we here examine if they can add two numbers of identical elements seen simultaneously. As soon as after three training days, the ants could respond significantly more to the sum of 1 + 1, 2 + 1, 3 + 1, and 3 + 2 elements than to the two initial numbers of elements seen during training and to the wrong sums 3, 4, 5 and 6 respectively. Their ability in giving the correct response seemed to somewhat decrease with increasing numbers to add. Twenty-four hours after the removal of the initial numbers presented during training, the ants no longer responded essentially to the correct sum of these numbers.
The Status Quo of College Students' Online Shopping Addiction and Its Coping Strategies
Authors: Zhang Jiahui , Bai Zhiqiang , Wei Jingxia , Yang Maolin , Fu Guifang
Published: May 2019

With the rapid development of science and technology, electronic payment platforms have become increasingly mature, and network consumption has become increasingly popular. As a special consumer group, more and more college students tend to become addicted to online shopping. This study examines the probability and difference of 183 college students' online shopping addiction, and puts forward the strategies to cope with it from four perspectives: individual, family, school and society. The results showed that 62.8% of college students were addicted to online shopping. There were significant gender differences in the sub-dimensions of excessive consumption, impaired function, truncation reaction and online shopping pleasure, and women scored higher than men. There are significant grade differences in the dimension of excessive consumption and functional impairment of online shopping addiction. The excessive consumption of freshmen is significantly higher than that of other grades. The scores of functional impairment dimension of freshmen and sophomores are significantly higher than that of other grades.
Teacher Perceptions of the New Mathematics and Science Curriculum: A Step Toward STEM Implementation in Saudi Arabia
Authors: Madani Rehaf A. , Forawi Sufian
Published: May 2019

STEM education has become one of the most rapidly growing sectors in educational reform globally. Whilst the program was successfully implemented in most countries, unfortunately the introduction in Saudi Arabia was not as successful due to a lack of clarity in the description of its meaning, purpose and framework of application. Although STEM is commonly recognized as a way of strengthening mathematics and science curricula, its exact implications are still unclear for any intervention or modification in any of the subjects related to science, mathematics, engineering and Technology, (STEM) implementation. In 2009, the Ministry of Education (MOE) introduced a new mathematics and science curriculum in a joint effort with Obeikan Research Development Company, as an adapted series of science and mathematics textbooks. The new adapted curricula attempt to make meaningful connection between student’s lives and their educational experiences through the implementation of new teaching practices which include student centred investigation strategies and problem-based learning.
THERMODYNAMIC ANALYSIS OF BEHAVIOUR IN A COMBINED CYCLES OPERATING WITH BIOGAS AND MUNICIPAL SOLID WASTE
Authors: GALLEGO A. , KUBO H. , GUTİERREZ-GOMEZ A. C. , BERECHE R. P. , NETO A. P. , ROCHA A. D.
Published: May 2019

The research and development of technologies using wastes have been advanced over the last decades. Along these lines, the use of biogas from landfills, and Municipal Solid Waste (MSW) as fuel has a relevant role in the context of energy generation and environmental protection. The use of MSW as fuel to produce energy has the advantage to abate the use of landfills, which are responsible for problems such as space loss and sanitation that large cities have to deal with. However, the MSW and biogas available in landfills have been used individually to generate power, or in systems where energy conversion is in development. Thus in this research the choosing of the technology that better fits in thermal conversion systems, using MSW and biogas, was carried out. The main technologies of thermal conversion of MSW, including gasification, pyrolysis, and incineration, were verified. Among the technologies above, incineration is the most and its present used in huge-sized facilities in the world. Regarding the most used technologies for thermal energy conversion of biogas, combustion in boilers, or engines and small turbines, can be addressed. Therefore, it is possible to verify that most of those systems can use many kinds of fuels; furthermore, there are many options to combine these technologies, for instance, using Combined Cycles. The present work aims to perform a thermodynamic analysis (energy and exergetic analyses) of a Combined Cycles composed of the internal combustion engine to burn biogas, and a gasification system of MSW combined with a system to burn syngas to produce steam and operate in a Rankine cycle. Because the MSW and biogas compositions are not singular over time, a thermodynamic analysis evaluating the influence was performed of this variation in the behavior of the power plant.
Effect of irreversibility and energy harvesting on entropy generation within a microscale heat sink
Authors: POURGHASEMİ Mahyar
Published: May 2019

In present work, the entropy generation minimization technique (EGM) is applied to study the performance of a microchannel heat sink combined with a new proposed parameter called irreversibility index and energy harvesting concept. Three different cases have been investigated using geometry of a microchanel heat sink selected from experimental work in the literature. The constraints considered in this study, are fixed channel height and maximum pressure drop. It has been observed that with fixed channel height constraint, while the aspect ratio changes from 1 to 10, the optimum operating condition fall in the range of Reynolds number equal to 2000 and aspectratio of 2.25. Moreover, the extra constrain on maximum pressure drop imposes a limitation on applicable aspect ratio range. The maximum aspect ratio of the channel for stable flow field in this case cannot be higher than 5 imposed by criteria of laminar flow regime. The obtained optimum values are Reynolds number of 1850 and aspect ratio of 2. Using a combined new defined irreversibility index and Energy Harvesting Concept (EHC), it has been shown that the optimum design values for industrial applications are not necessary ones obtained from EGM method and may shift to a new operating point based on the method considered for energy harvesting.
Asymptotic behavior for a class of delay differential equations with a forcing term
Authors: Liu Yuji
Published: May 2019

We study the asymptotic behavior of solutions of the following forced delay differential equation $$ x'(t)=-p(t)f(x(t-\tau))+r(t),\quad t\ge 0.  \eqno{(*)}$$ It is show that if $ f$ is increasing and $ |f(x)|\le |x|$ for all $ x\in R$, $ \lim_{t\to +\infty} {r(t)\over p(t)}=0$, $ \int_0^{+\infty} p(s)ds=+\infty$ and $ \limsup_{t\to+\infty} \int_{t-\tau}^t p(s)ds
On trapezoid and Gr"uss like integral inequalities
Authors: Pachpatte B. G.
Published: May 2019

In the present paper we establish some new integral inequalities similar to that of Trapezoid and Gr"uss inequalities by using a fairly elementary analysis.
Degree of approximation of conjugate of Lip $ \alpha$ class function by $ {K^\lambda}$-summability means of conjugate series of a Fourier series
Authors: Lal Shyam , Singh Gopal Krishna
Published: May 2019

In this paper the degree of approximation of conjugate of a function belonging to Lip $ \alpha$ class by $ K^\lambda$-summability means of conjugate series of its Fourier series has been determined.
Generalized sequence space ${F(X,r)}$
Authors: Ghosh D. , Srivastava P. D.
Published: May 2019

In this paper, we define and study vector valued sequence space $F(X,r)$. Few topological properties, inclusion relation, boundedness properties of subset are studied for this class.
On the Blaschke approach of ruled surface
Authors: Baky Rashad A. Abdel
Published: May 2019

In this paper using E. Study map and the Blaschke approach we studied a ruled surface as a curve on the dual unit sphere. The Blaschke approach proceeds by defining a sequence of ruled surfaces associated with the ruled surface. The relative positions of these surfaces and their distribution parameters characterize the local properties of the original surface. A necessary condition for a ruled surface to be closed is derived. Moreover, an example of application is investigated in detail.
A note on common fixed points by altering distances
Authors: Pant R. P. , Jha K. , Lohani A. B.
Published: May 2019

The purpose of this paper is to provide answer to an open problem due to Sastry et al. [1].
On common fixed points by altering distances between the points
Authors: Pant R. P. , Jha K. , Padaliya S.
Published: May 2019

The aim of the present paper is to obtain an answer to an open problem due to Sastry et al. [5] by using the relationship between the continuity and reciprocal continuity of mappings in the setting of control functions which alter distances.
New generalization of H. Alzer's inequality
Authors: Liu Zheng
Published: May 2019

A new generalization of H. Alzer's inequality is proved. This inequality generalizes both results in an article by N. Elezovic and J. Pecaric (J. Math. Anal. Appl. 223 (1998), 366--369) as well as an article by Feng Qi (J. Math. Anal. Appl. 240 (1999), 294--297). It is shown that this inequality is satisfied for a large class of increasing convex sequences.
Some uniformly starlike functions with varying arguments
Authors: Vijaya K. , Murugusundaramoorthy G.
Published: May 2019

In this paper two new subclasses of starlike functions that are analytic and normalized in the open unit disc with varying arguments is introduced. For functions in these classes we obtained coefficient bound, distortion results and the extreme points.
Stability of linear functional equations in Banach modules
Authors: Park Chun-Gil
Published: May 2019

We prove the Hyers-Ulam-Rassias stability of the linear functional equation in Banach modules over a unital Banach algebra.
Strongly starlike functions associated with the Dziok-Srivastava operator
Authors: Liu Jin-Lin
Published: May 2019

In terms of the Dziok-Srivastava operator, we introduce and study some new classes of strongly starlike functions. Certain properties of these subclasses are studied.
On the approximation of function belonging to weighted $ {(L^p, \xi(t))}$ class by almost matrix summability method of its Fourier series
Authors: Lal Shyam
Published: May 2019

In this paper, the degree of approximation of function belonging to weighted $ W(L^p$, $ \xi(t))$ class by almost matrix summability of its Fourier series has been determined. The main theorem improves all the previously known theorems in this line of work.
On new generalizations of Hilbert's inequalities
Authors: Lu Zhongxue
Published: May 2019

In this paper, some generalizations of Hilbert's inequalities are shown by introducing two real functions $ \phi(x)$ and $ \psi(x)$.
Plucked-keyboard instruments built in Flanders as based on the collection of the Muziekinstrumentenmuseum in Brussels
Authors: Stachowiak Monika
Published: May 2019

The article touches on the topic of keyboard-plucked instruments, which were made in one of the most significant European centres – Flanders. The Ruckers family working there created unique works serving as an inspiration for subsequent generations of instrument makers as well as modern makers of copies of historical instruments. The text is aimed at presenting the history of Flanders and instrument building in that region, and analysing selected exhibits from the Muziekinstrumentenmuseum in Brussels. The names of authors of numerous old instruments still need to be determined or confirmed, and a thorough study of connections between families of builders, their relations with other makers, and the ornaments placed on instruments, may facilitate the identification.
The article describes the history of the Guild of Saint Luke in Antwerp, uniting artists and instrument makers. The most recognised representatives of this group were the Ruckers and the Couchet families, and biographical sketches of their selected members are presented further along in the article. There is also a description of different instruments from that region, such as: harpsichord (Flűgel), virginal, spinet, muselar, de moeder met het kind and ottavino. The conclusion includes an analysis of selected items from the Belgian museum which come from the region of Flanders and were built by the Ruckers and Rouchet families. These exhibits are distinguished by their structure, external appearance and history. The descriptions and photos will allow readers to learn more about the presented material.
The text is addressed to people interested in the topic of the plucked-keyboard instrument making, as well as to harpsichordists who need to know about the origin of instruments. This kind of information is crucial for adjusting the right temperament, registers and articulation in a given piece. The knowledge about the types of historical keyboard instruments is equally important.
Piano concerto no. 1 by Andrzej Nikodemowicz – a hidden desire for freedom
Authors: Nidecka Ewa
Published: May 2019

Piano concerto no. 1 (1994) by Andrzej Nikodemowicz (1925-2017) is among seven piano concertos written by the composer. Its first version is the Violin concerto created in 1973. Because of the difficult violin part, the composer remade the composition for the piano. The first performance of the Piano concerto no. 1 took place in 1998 in Lviv.
While writing the piece, Andrzej Nikodemowicz was persecuted by the Soviet authorities in Lviv for his religious views, that is why the piece expresses his hidden desire for creative freedom. It remains close to expressionist tradition influenced by Scriabin and his idea of “unhindered power of artistic creation” and “apotheosis of the freedom of creative spirit” . The proof for the expressionist origin of Piano concerto no. 1 are the lack of melodic lines, significant dispersion of sound material, loosened rhythmic relationships, lack of tonal centralisation (full atonalism) and a special kind of musical material formation that places the tension layer on extremely different poles: from arhythmic, muffled, slowed, veiled and dreamlike, to a cascade of scattered tones and harmonies preferring sharp, extensive dissonances, passages which are maximally dense in terms of rhythm and divergent, leading to an explosion of drama. The shape of the piano part indicates a clear analogy to an expressionist character – alienated, contradicted and conflicted with the world, experiencing loneliness and suffering.
Piano concerto no. 1 by Andrzej Nikodemowicz was also influenced by other 20th century composers, such as B. Bartók and I. Stravinsky (new kind of expression manifested e.g. in impulsive rhythm) and W. Lutosławski (aleatorism).
„Land zurück !“ Arbeiter, Abwertung, AfD
Authors: Dörre Klaus
Published: May 2019

Der Beitrag beschäftigt sich mit rechtspopulistischen Orientierungen, wie sie unter gewerkschaftlich organisierten Arbeitern verbreitet sind. Anhand empirischer Studien beleuchtet er einen Modus kollektiver Abwertungen, der jenen Problemrohstoff erzeugt, den die radikale Rechte nutzt, um die soziale Frage mit eigenen Inhalten zu besetzen. Er rekonstruiert die Tiefengeschichte aktiver Gewerkschafter und Betriebsräte, die offen mit der Af D oder noch weiter rechtsstehenden Organisationen sympathisieren. Lohnabhängige im Osten empfinden sich häufig einer besonderen Klasse zugehörig, die durch kollektive Abwertung entsteht. Diese Abwertungslogik zu durchbrechen kann zum Ansatzpunkt gewerkschaftlicher Gegenstrategien werden.