Influence of Embankments with Parapets on the Cross-Wind Turbulence Intensity at the Contact Wire of Railway Overheads

Winds as an environmental factor can cause significant difficulties for the railway system operation. The railway overhead has been particularly vulnerable to cross-winds related problems, such as development of undamped oscillations due to galloping phenomenon. The installation of windbreaks to decrease the aerodynamic loads on the train can affect the loads on railway overheads triggering cable galloping. One essential parameter to indicate the influence of the parapet wake on the catenary contact wire is the turbulence intensity. In this paper the results of an experimental analysis of the turbulence intensity due to the presence of parapets carried out in a wind tunnel are reported. Embankments equipped with different parapets have been tested and turbulence intensity has been measured at both contact wire locations, windward and leeward. The relative influence of the parapets is measured through a reduced turbulence intensity, defined as the ratio between the turbulence intensity measured with parapet and the turbulence intensity in the case without any parapet on the embankment. In general the reduced turbulence intensity increases as the height of the parapet increases

Spanish researchers’ opinions, attitudes and practices towards open access publishing

The open access (OA) movement has exploded in the last few years. In 2016 we invited 1,896 researchers based in Spanish institutions to fill in a survey on their opinion, attitudes and practices towards OA. We analysed the 554 responses received from researchers in all fields of knowledge (29% response ratio). Most researchers are aware of OA outlets in their fields (86%) and believe OA is beneficial (76%). There isn’t a clear position on the quality of OA journals among Spain-based researchers and there are differences between disciplines. Almost 70% of researchers have published at least one OA article in the last 5 years. Half of them had to pay article processing charges (APCs) that were covered with research funds

A simplified approach to determine aerodynamic damping of railway overheads

The railway overhead (or catenary) is the system of cables responsible for providing electric current to the train. This system has been reported as wind-sensitive (Scanlon et al., 2000), and particularly to the occurrence of galloping phenomena. Galloping phenomena of the railway overhead consists of undamped cable oscillations triggered by aerodynamic forces acting on the contact wire. As is well known, aerodynamic loads on the contact wire depends on the incident flow mean velocity and the angle of attack. The presence of embankments or hills modifies both vertical velocities profiles and angles of attack of the flow (Paiva et al., 2009). The presence of these cross-wind related oscillations can interfere with the safe operation of the railway service (Johnson, 1996). Therefore a correct modelling of the phenomena is required to avoid these unwanted oscillations

Towards the Definition of Test Coverage Criteria for RESTful Web APIs

Web APIs following the REST architectural style (so-called RESTful Web APIs) have become the de-facto standard for software integration. As RESTful APIs gain momentum, so does the testing of them. However, there is a lack of mechanisms to assess the adequacy of testing approaches in this context, which makes it difficult to mea sure and compare the effectiveness of different testing techniques. In this work-in-progress paper, we take a step forward towards a framework for the assessment and comparison of testing approaches for RESTful Web APIs. To that end, we propose a preliminary catalogue of test coverage criteria. These criteria measure the adequacy of test suites based on the degree to which they exercise the different input and output elements of RESTful Web services. To the best of our knowledge, this is the first at tempt to measure the adequacy of testing approaches for RESTful Web APIs.Ministerio de Economía y Competitividad BELI (TIN2015-70560-R)Ministerio de Ciencia, Innovación y Universidades RTI2018-101204-B-C21 (HORATIO)Ministerio de Educación, Cultura y Deporte FPU17/0407

RESTest: automated black-box testing of RESTful web APIs

Testing RESTful APIs thoroughly is critical due to their key role in software integration. Existing tools for the automated generation of test cases in this domain have shown great promise, but their applicability is limited as they mostly rely on random inputs, i.e., fuzzing. In this paper, we present RESTest, an open source black box testing framework for RESTful web APIs. Based on the API specification, RESTest supports the generation of test cases using different testing techniques such as fuzzing and constraint-based testing, among others. RESTest is developed as a framework and can be easily extended with new test case generators and test writers for different programming languages. We evaluate the tool in two scenarios: offline and online testing. In the former, we show how RESTest can efficiently generate realistic test cases (test inputs and test oracles) that uncover bugs in real-world APIs. In the latter, we show RESTest’s capabilities as a continuous testing and monitoring framework. Demo video: https://youtu.be/1f_tjdkaCKo.Junta de Andalucía APOLO (US-1264651)Junta de Andalucía EKIPMENT-PLUS (P18-FR-2895)Ministerio de Ciencia, Innovación y Universidades RTI2018-101204-B-C21 (HORATIO)Ministerio de Educación, Cultura y Deporte FPU17/0407

Analyzing the Behavior of Cannabis Users during the COVID-19 Confinement in Spain

The impact of the COVID-19 pandemic on our lives is unquestionable, including in the area of substance consumption. This study aimed to evaluate the changes in the pattern of cannabis use during the Spanish COVID-19 lockdown and confinement, and to analyze the variations in the reported motives for cannabis use and withdrawal symptoms. A cross-sectional retrospective study was conducted between April and May 2020, using an instrument that included two time points. Time 1 collected retrospective information on the participants’ habits (N = 89; 73% male; mean age = 29.01) prior to confinement and Time 2 collected the same information during the confinement. Sociodemographic data were collected, as well as the frequency of substance use, cannabis use patterns, sources of cannabis, perceived availability of drugs and cannabis price, and the Marijuana Motives Measure questionnaire and the Cannabis Withdrawal Scale were used. Results showed a decrease in both cannabis use and consumption due to enhancement and social motives. All reported sources of cannabis experienced a reduction except for the Internet, which experienced a significant increase. There was a positive correlation between withdrawal symptoms and coping motives before and during the lockdown. These findings will allow professionals to better develop both prevention and intervention strategies

Tras la leche ¿nada eches? Trabajando con mezclas

El estudio de la materia y las mezclas suelen tratarse a través de actividades de lápiz y papel centrados en clasificarlas. Para mejorar su comprensión, en el presente trabajo, se estudiar al mismo tiempo las mezclas y las sustancias. Además, se intenta ubicarlas en la vida real mediante una propuesta de indagación de nutrición. Los resultados muestran que poder tocar y practicar diferentes mezclas a la par que se trabaja con el libro de texto, mejora su comprensión e identificación. Sin embargo, los estudiantes no están acostumbrados a generar hipótesis y extraer conclusiones, lo que dificulta mostrarles procesos de la vida real en los que están implicadas las mezclas

Demostración de la plataforma educativa eLab3D para el aprendizaje de la electrónica

eLab3D es un laboratorio remoto que permite a los usuarios la realización de experimentos reales online basados en el análisis y diseño de circuitos electrónicos. El laboratorio dispone como interfaz de un mundo virtual 3D, desarrollado en Opensim, en el que los usuarios interaccionan con réplicas virtuales de instrumentos, circuitos, componentes o cables, así como con sus compañeros y profesores a la hora de realizar las prácticas. eLab3D se ha diseñado para que todas las actividades que se desarrollen sean prácticamente análogas a las que se realizarían en un laboratorio presencial

Utilización del laboratorio remoto eLab3D en la enseñanza de la electrónica analógica

Este trabajo muestra el grado de adquisición de los objetivos de aprendizaje que pueden alcanzar los estudiantes en un laboratorio de electrónica mediante la utilización de eLab3D. Además se presentan los resultados obtenidos en una experiencia realizada con estudiantes de una titulación de grado de la Universidad Politécnica de Madrid en la que se ha evaluado la eficacia, a nivel de aprendizaje, al utilizar la plataforma eLab3D