Assessment of the worthwhileness of efficient driving in railway systems with high-receptivity power supplies

Eco-driving is one of the most important strategies for significantly reducing the energy consumption of railways with low investments. It consists of designing a way of driving a train to fulfil a target running time, consuming the minimum amount of energy. Most eco-driving energy savings come from the substitution of some braking periods with coasting periods. Nowadays, modern trains can use regenerative braking to recover the kinetic energy during deceleration phases. Therefore, if the receptivity of the railway system to regenerate energy is high, a question arises: is it worth designing eco-driving speed profiles? This paper assesses the energy benefits that eco-driving can provide in different scenarios to answer this question. Eco-driving is obtained by means of a multi-objective particle swarm optimization algorithm, combined with a detailed train simulator, to obtain realistic results. Eco-driving speed profiles are compared with a standard driving that performs the same running time. Real data from Spanish high-speed lines have been used to analyze the results in two case studies. Stretches fed by 1 × 25 kV and 2 × 25 kV AC power supply systems have been considered, as they present high receptivity to regenerate energy. Furthermore, the variations of the two most important factors that affect the regenerative energy usage have been studied: train motors efficiency ratio and catenary resistance. Results indicate that the greater the catenary resistance, the more advantageous eco-driving is. Similarly, the lower the motor efficiency, the greater the energy savings provided by efficient driving. Despite the differences observed in energy savings, the main conclusion is that eco-driving always provides significant energy savings, even in the case of the most receptive power supply network. Therefore, this paper has demonstrated that efforts in improving regenerated energy usage must not neglect the role of eco-driving in railway efficiency

Quintessence and the Swampland: The Parametrically Controlled Regime of Moduli Space

We provide evidence that slow roll is not possible in any parametrically controlled regime of the moduli space of string theory. This is proven in full generality in the asymptotic limit of the moduli space of type II and heterotic Calabi-Yau compactifications for the dilaton and any number of Kähler moduli. Our results suggest that in order to build quintessence into string theory one must work in the interior of moduli space where numerical, even if not parametric, control could still be achieved

Results of the meteorological model WRF-ARW over Catalonia, using different parameterizations of convection and cloud microphysics

The meteorological model WRF-ARW (Weather Research and Forecasting - Advanced ResearchWRF) is a new generation model that has a worldwide growing community of users. In theframework of a project that studies the feasibility of implementing it operationally at the Mete-orological Service of Catalonia, a verification of the forecasts produced by the model in severalcases of precipitation observed over Catalonia has been carried out. Indeed, given the impor-tance of precipitation forecasts in this area, one of the main objectives was to study the sensitivityof the model in different configurations of its parameterizations of convection and cloud micro-physics. In this paper, we present the results of this verification for two domains, a 36-km gridsize and one of 12 km grid size, unidirectionally nested to the previous one. In the externaldomain, the evaluation was based on the analysis of the main statistical parameters (ME andRMSE) for temperature, relative humidity, geopotential and wind, and it has been determinedthat the combination using the Kain-Fritsch convective scheme with the WSM5 microphysicalscheme has provided the best results. Then, with this configuration set for the external domain,some forecasts at the nested domain have been done, by combining different convection andcloud microphysics schemes, leading to the conclusion that the most accurate configuration isthe one combining the convective parameterization of Kain-Fritsch and the Thompson micro-physics scheme

Goos-Hanchen shift of Cosine-Gaussian Schell-model beams with rectangular symmetry

In this contribution we study the relation between the second order intensity moments and the Goos-Hanchen shift for partially coherent totally polarized beams. The results are applied to a type of partially coherent beams, the Cosine-Gaussian Schell-model beams with rectangular symmetry

Improving QPF by blending techniques at the Meteorological Service of Catalonia

The current operational very short-term and short-term quantitative precipitation forecast (QPF) at the Meteorological Service of Catalonia (SMC) is made by three different methodologies: Advection of the radar reflectivity field (ADV), Identification, tracking and forecasting of convective structures (CST) and numerical weather prediction (NWP) models using observational data assimilation (radar, satellite, etc.). These precipitation forecasts have different characteristics, lead time and spatial resolutions. The objective of this study is to combine these methods in order to obtain a single and optimized QPF at each lead time. This combination (blending) of the radar forecast (ADV and CST) and precipitation forecast from NWP model is carried out by means of different methodologies according to the prediction horizon. Firstly, in order to take advantage of the rainfall location and intensity from radar observations, a phase correction technique is applied to the NWP output to derive an additional corrected forecast (MCO). To select the best precipitation estimation in the first and second hour (t+1 h and t+2 h), the information from radar advection (ADV) and the corrected outputs from the model (MCO) are mixed by using different weights, which vary dynamically, according to indexes that quantify the quality of these predictions. This procedure has the ability to integrate the skill of rainfall location and patterns that are given by the advection of radar reflectivity field with the capacity of generating new precipitation areas from the NWP models. From the third hour (t+3 h), as radar-based forecasting has generally low skills, only the quantitative precipitation forecast from model is used. This blending of different sources of prediction is verified for different types of episodes (convective, moderately convective and stratiform) to obtain a robust methodology for implementing it in an operational and dynamic wa

Aromatic, Sensory, and Fatty Acid Profiles of Arbequina Extra Virgin Olive Oils Produced Using Different Malaxation Conditions

The demand for high-quality extra virgin olive oil (EVOO) is growing due to its unique characteristics. The aroma and flavor of EVOO depend on its content of volatile organic compounds (VOCs), whose formation is affected by the olive variety and maturity index, and the oil production process. In this study, the sensory quality and VOC and fatty acid (FA) profiles were determined in Arbequina olive oils produced by applying different malaxation parameters (20, 25, and 30 °C, and 30 and 45 min). All the olive oils were classified as EVOO by a sensory panel, regardless of the production conditions. However, cold extraction at 20 °C resulted in more positive sensory attributes (complexity). The FA concentration increased significantly with the malaxation temperature, although the percentage profile remained unaltered. Finally, an OPLS-DA model was generated to identify the discriminating variables that separated the samples according to the malaxation temperature. In conclusion, the tested range of malaxation parameters appeared not to degrade the distinctive attributes/organoleptic profile of olive oil and could be applied to obtain an EVOO of high sensory quality, especially at 20 °C

Observed trends and changes in Extreme Climate Indices over the Pyrenees (1959-2015)

Póster presentado en: EMS Annual Meeting: European Conference for Applied Meteorology and Climatology celebrado del 9 al 13 de septiembre de 2017 en Copenhague, Dinamarca.CLIMPY (Characterisation of the evolution of climate and provision of information for adaptation in the Pyrenees) is a transboundary project that aims to perform a detailed analysis of recent trends in temperature, precipitation and snow cover in the Pyrenees, and their future projection. As a result, changes in the frequency, intensity, spatial extent, duration and timing of weather and climate extremes due to climate change are among the more relevant objectives.This project (EFA081/15) is under the umbrella of the Pyrenees Climate Change Observatory (OPCC-CTP), and it has a 65% funding by the European Regional Development Fund (FEDER) through the Interreg Programme V-A Spain-France-Andorra (POCTEFA 2014-2020)

Environmental variability in aquatic ecosystems: avenues for future multifactorial experiments

The relevance of considering environmental variability for understanding and predicting biological responses to environmental changes has resulted in a recent surge in variability-focused ecological research. However, integration of findings that emerge across studies and identification of remaining knowledge gaps in aquatic ecosystems remain critical. Here, we address these aspects by: (1) summarizing relevant terms of variability research including the components (characteristics) of variability and key interactions when considering multiple environmental factors; (2) identifying conceptual frameworks for understanding the consequences of environmental variability in single and multi-factorial scenarios; (3) highlighting challenges for bridging theoretical and experimental studies involving transitioning from simple to more complex scenarios; (4) proposing improved approaches to overcome current mismatches between theoretical predictions and experimental observations; and (5) providing a guide for designing integrated experiments across multiple scales, degrees of control, and complexity in light of their specific strengths and limitations

Beneficial effects of word final stress in segmenting a new language: evidence from ERPs

Background: How do listeners manage to recognize words in an unfamiliar language? The physical continuity of the signal, in which real silent pauses between words are lacking, makes it a difficult task. However, there are multiple cues that can be exploited to localize word boundaries and to segment the acoustic signal. In the present study, word-stress was manipulated with statistical information and placed in different syllables within trisyllabic nonsense words to explore the result of the combination of the cues in an online word segmentation task. Results: The behavioral results showed that words were segmented better when stress was placed on the final syllables than when it was placed on the middle or first syllable. The electrophysiological results showed an increase in the amplitude of the P2 component, which seemed to be sensitive to word-stress and its location within words. Conclusion: The results demonstrated that listeners can integrate specific prosodic and distributional cues when segmenting speech. An ERP component related to word-stress cues was identified: stressed syllables elicited larger amplitudes in the P2 component than unstressed ones