Mejoras en el estudio y predicción de los campos de viento locales, especialmente en entornos aeroportuarios, con importante afectación a la seguridad del tráfico aéreo = Improvements in the study and prediction of local wind fields, particularly in airport surroundings, with implication in air traffic safety

197 p.El viento es un elemento esencial en la climatología. La predicción y la medición de los campos de vientos son los dos aspectos clave en torno a los cuales pivota nuestro conocimiento de los mismos, la predicción de vientos se realiza fundamentalmente mediante técnicas de cálculo numérico, con un modelo númerico modificado se han realizado nuevos ensayos de validación, pasando posteriormente a la realización de las simulaciones globales para el entorno del Aeropuerto de Leó

Antes de Sevilla: Lorenzo Mercader (Mercadante) de Bretaña en Zaragoza (doc. 1446-1448). Transferencias e intercambios entre las Coronas de Aragón y Castilla a mediados del siglo XV

Hasta ahora, no disponíamos de ningún dato sobre la trayectoria profesional de Lorenzo Mercader de Bretaña antes de su llegada a Sevilla en 1454. En este artículo presentamos su firma con el escultor Fortaner de Usesques, suscrita en Zaragoza en 1446 y cancelada dos años más tarde; un periodo de tiempo en el que, además de poder participar en los compromisos asumidos por Usesques, el bretón tendrá ocasión de conocer los trabajos desarrollados por Isambart, Pedro Jalopa, Antoni Dalmau y otros maestros de procedencia valenciana en la catedral de la capital aragonesa. Su paso por la ciudad del Ebro permite inscribirle dentro de la dinámica protagonizada por aquellos profesionales que trabajaron en la Corona de Aragón antes de recalar en la catedral de Sevilla, iniciada por Isambart y continuada por Carlín, e incluso es posible que también por el propio Antoni Dalmau, probable autor del diseño para la fachada de los pies, en cuya decoración escultórica terminará trabajando Lorenzo Mercader. Up until now the career of Lorenzo Mercader of Bretagne remained unknown before his arrival in Seville in 1454. This article sheds some light on his life prior to that date by publishing an indenture that bound him to the sculptor Fortaner de Usesques. The indenture was signed in Saragossa in 1446 and cancelled two years later. During this period, the Breton would have the chance to take part in works carried out by Usesques, but also to know firsthand the works in the cathedral of Saragossa undertaken by Isambart, Pedro Jalopa, Antoni Dalmau, and other masters of Valencian origins. Lorenzo Mercader’s stay in the Aragonese capital allows us to insert him into the dynamic of artists who worked in the Crown of Aragon before heading to the cathedral of Seville. Among this group of artists we can name Isambart, the founder, and continuators such as Carlín and, maybe, Antoni Dalmau, who probably designed the west façade of the Andalusian cathedral, where Lorenzo Mercader ended up working on its sculptural decoration

Single-photon source over the terahertz regime

We present a proposal for a tunable source of single photons operating in the terahertz (THz) regime. This scheme transforms incident visible photons into quantum THz radiation by driving a single polar quantum emitter with an optical laser, with its permanent dipole enabling dressed THz transitions enhanced by the resonant coupling to a cavity. This mechanism offers optical tunability of properties such as the frequency of the emission or its quantum statistics (ranging from antibunching to entangled multi-photon states) by modifying the intensity and frequency of the drive. We show that the implementation of this proposal is feasible with state-of-the-art photonics technology.Comment: 18 pages, 14 figure

Mechanistic Insights into Alzheimer’s Disease Unveiled through the Investigation of Disturbances in Central Metabolites and Metabolic Pathways

Hydrophilic metabolites are closely involved in multiple primary metabolic pathways and, consequently, play an essential role in the onset and progression of multifactorial human disorders, such as Alzheimer's disease. This review article provides a comprehensive revision of the literature published on the use of mass spectrometry-based metabolomics platforms for approaching the central metabolome in Alzheimer's disease research, including direct mass spectrometry, gas chromatography-mass spectrometry, hydrophilic interaction liquid chromatography-mass spectrometry, and capillary electrophoresis-mass spectrometry. Overall, mounting evidence points to profound disturbances that affect a multitude of central metabolic pathways, such as the energy-related metabolism, the urea cycle, the homeostasis of amino acids, fatty acids and nucleotides, neurotransmission, and others

Stochastic optimization of high-altitude airship envelopes based on kriging method

[EN] High-altitude airships can be used to transport substantial payloads to the stratosphere and remain there over long periods of time. In this paper, an algorithm for the design of high-altitude airship envelopes, accounting for uncertainties, is developed and applied. The algorithm is based on the non-intrusive polynomial chaos expansion scheme, which is employed to build a stochastic kriging metamodel. Two uncertainties are examined and characterized: 1) the stratospheric wind fluctuations using reanalysis datasets and 2) the variability in the turbulence levels. The method results are discussed to address the relevancy of the uncertainties. It is found that the drag coefficient of stratospheric envelopes can vary by as much as 30 percent. As a case of study, an ideal stratospheric airship is considered, operating at an altitude of 20 km, at a latitude of 30cN and carrying a payload of 250 kg. The baseline design follows the shape of the ZHIYUAN-1 envelope and the cost function to be minimized is the average mission drag coefficient. Due to the new method, a significant reduction (4%) of the average drag of the aircraft is achieved.S

An analysis and enhanced proposal of atmospheric boundary layer wind modelling techniques for automation of air traffic management

Production and hosting by Elsevier[EN] The air traffic management automation imposes stringent requirements on the weather models, in such a way that they should be able to provide reliable short-time forecasts in digital formats in almost real time. The atmospheric boundary layer is one of the regions where aircraft operation and coordination are critical and therefore atmospheric model performance is also vital. This paper presents conventional and innovative techniques to improve the accuracy in the forecasting of winds in the lower atmospheric layer, proposing mechanisms to develop better models including deterministic and stochastic simulations. Accuracy is improved by optimizing the grid, assimilating observations in cycling simulations and managing a number of ensemble members. An operation-driven post-processing stage helps to incorporate detailed terrain definitions and real-time observations without re-running the model. The improvements are checked against mesoscale weather simulations at different scales and a dedicated flight campaign. The results show good performance of the model without sensitively increasing the required throughput.SIBoeing Research & Technology Europ

Atmospheric Boundary Layer Wind Profile Estimation Using Neural Networks Applied to Lidar Measurements

[EN] This paper introduces a new methodology for estimating the wind profile within the ABL (Atmospheric Boundary Layer) using a neural network and a single-point near-ground measurement. An important advantage of this solution when compared with others available in the literature is that it only requires near surface measurements for the prognosis once the neural network is trained. Another advantage is that it can be used to study the wind profile temporal evolution. This work uses data collected by a lidar sensor located at the Universidad de León (Spain). The neural network best configuration was determined using sensibility analyses. The result is a multilayer perceptron with three layers for each altitude: the input layer has six nodes for the last three measurements, the second has 128 nodes and the third consists of two nodes that provide u and v. The proposed method has better performance than traditional methods. The obtained wind profile information obtained is useful for multiple applications, such as preliminary calculations of the wind resource or CFD models.S

A 3D printed f5 Newtonian telescope: Development of a student project for outreach, education, and dissemination

An Engineering student´s Final Degree Project based on the design and manufacturing of a 3D printed telescope is presented. The project involves both optical, mechanical, and electronic design, the construction of the instrument, and the numerical and experimental analysis of the prototype. Furthermore, the project explores the possibilities offered by the current 3D printed technologies for the manufacturing of telescopes that may be used both for teaching and disseminating Astronomy and the basis on how to build such instruments. In this communication the current development of a student Final’s Degree Project, consisting of the design and construction of a 3D printed Newtonian telescope, is presented. Both the project and the learning experience are shown as an example of the possibilities of this kind of study at the final stages of the academic formation of engineers, and the possibilities for outreach, education and dissemination of both science and engineering are explored

Atmospheric Boundary Layer Wind Profile Estimation Using Neural Networks, Mesoscale Models, and LiDAR Measurements

[EN] This paper introduces a novel methodology that estimates the wind profile within the ABL by using a neural network along with predictions from a mesoscale model in conjunction with a single near-surface measurement. A major advantage of this solution compared to other solutions available in the literature is that it requires only near-surface measurements for prediction once the neural network has been trained. An additional advantage is the fact that it can be potentially used to explore the time evolution of the wind profile. Data collected by a LiDAR sensor located at the University of León (Spain) is used in the present research. The information obtained from the wind profile is valuable for multiple applications, such as preliminary calculations of the wind asset or CFD modeling.SIERDF A way of making Europ

Station-keeping HAPS mission through optimal sprint and drift trajectories

[EN] Due to the latest technological breakthroughs, High-Altitude Pseudo Satellites (HAPS) have recently become a feasible solution with great potential in the aerospace industry for Earth observation and communications, among other applications. Minimizing the energy consumption of these solar powered platforms is critical and, in the case of lighter than air vehicles, leads to smaller and more manageable platforms. When stratospheric airships perform a station-keeping mission, a certain displacement from the Earth surface reference point is usually admissible. This flexibility makes it possible to define an optimal control law for the airship that minimizes the energy required to fly in a 24-hour cycle, leading to a sprint and drift trajectory. This study analyzes the impact on the energy balance of the mission that stems from the changes in the allowed station-keeping radius. It also considers the effects of the daylight hours, the wind intensity, and the characteristics of the onboard energy system. The associated optimal control problems are rigorously solved numerically by means of a transcription method with regularization. The results define the optimal sprint and drift trajectories adapted to every scenario, providing the time evolution of the available power that controls the flight. The analysis indicates that following the optimal trajectory leads to weight savings in the energy system of about 5.4 kilograms per kilometer of the station-keeping radius. It entails that, for example, if a 20 kilometer radius is allowed, the energy required decreases more than 6% and the payload capacity increases about a 43% when compared to the fixed-point flight.SIPublicación en abierto financiada por el Consorcio de Bibliotecas Universitarias de Castilla y León (BUCLE), con cargo al Programa Operativo 2014ES16RFOP009 FEDER 2014-2020 DE CASTILLA Y LEÓN, Actuación:20007-CL - Apoyo Consorcio BUCL