Evaluating the Effectiveness of Shielding Material, Vehicle Shape and Astronaut Position for Deep Space Travel

Background: As future crewed, deep space missions are being planned, it is important to assess how spacecraft design can be used to minimize radiation exposure. Collectively with shielding material, vehicle shape and astronaut position must be used to protect astronauts from the two primary sources of space radiation: Galactic Cosmic Rays (GCRs) and Solar Particle Events (SPEs). Methods: The On-Line Tool for the Assessment of Radiation in Space (OLTARIS) version 4.1 analysis package is used to evaluate and analyze this detailed radiation field. Developed by the National Aeronautics and Space Administration\u27s (NASA) Langley Research Center, the tool enables engineering and research related space radiation calculations. Each configuration is evaluated in whole body effective dose equivalent (ED). This research evaluates 70 aerospace materials, 2 vehicle shapes and 3 astronaut positions. Results and Conclusions: The material analyses show that for metals, aluminum outperforms and therefore is the most feasible metal for deep space travel. But when evaluating all materials, polyethylene outperforms all feasible aerospace materials. The vehicle shape and astronaut position analyses show that moving a human phantom closer to a wall does significantly decrease the ED. This pattern is not dependent on material nor boundary condition, but the mean shielding thickness a source ray must travel through for the GCR boundary condition. For shielding thicknesses greater than 30 g/cm 2 for polyethylene and 100g/cm 2 for aluminum, the results suggest that having astronauts’ habitats and work areas located further from the center will help protect astronauts longer from deep space radiation.https://scholarscompass.vcu.edu/gradposters/1067/thumbnail.jp

An assessment of electric vehicles and vehicle to grid operations for residential microgrids

Electric Vehicles (EVs) are a rapidly growing technology which can lower greenhouse-gas emissions in the transport and energy sectors. The EV batteries can discharge the stored energy back to grid, also known as Vehicle-to-Grid (V2G) which can support the integration of variable distributed renewable generation. Previous research identified financial barriers to the implementation of V2G, however, recent advancements in battery technology present new opportunities to make V2G technology viable. Using the current and predicted EV technology trends, this paper evaluates the annual operation and benefits of EVs and V2G in a microgrid environment and demonstrates different modes of operation. Guided by the gaps identified in the literature, one of the main contributions of this research is to uncover the impact of EV charging scenarios on the V2G operations. Furthermore, the research reveals the interactions between V2G and variable renewable generation coupled with utility scale battery over yearlong simulations to assess seasonal characteristics of V2G operations, which was mostly unexplored to date. Simulation results indicate that the operation of V2G in an optimised microgrid environment improves the economic operation of the system and reduces the levelized cost of electricity by up to 5.7%. Additionally, V2G provides more benefit to grids with higher solar generation proportion The results suggest that the latest advancements in EV technology have improved the economic viability of V2G as well as its potential to improve grid efficiency through providing additional storage capacity and peak demand management

Can ammonium stress be positive for plant performance?

In this article, we propose a change of paradigm where ammonium nutrition may be considered not exclusively as an undesirable situation for plant performance, but as a way to provoke changes in plant metabolism that can be beneficial for crop quality and plant physiology. While some of the positive effects of ammonium referred here still require further evaluation, the cross-tolerance induction of NH+4 to certain subsequent stresses, notably salinity, is clear. However, the molecular actors governing these interactions are almost completely unknown, and future works will be essential in order to fully exploit the benefits of ammonium-based fertilizers.This work was funded by the Basque Government (IT-932-16) and the Spanish Ministry of Economy and Competitiveness (Grants BIO2017-84035-R and AGL2017-86293-P, both co-funded by FEDER)

Arquitecturas

Desde sus inicios, la representación arquitectónica ha sido una constante en la obra de Daniel Bilbao. Esos testimonios de la intervención del hombre en el entorno constituyen el motivo principal de sus cuadros, a veces desde un lenguaje cercano a la abstracción, como en sus Cartografías, y en otras desde la figuración, recreando ambientes industriales, ferroviarios o portuarios

Daniel Bilbao. Pinturas y collages

Siguiendo la herencia de la vanguardia en el empleo del collage como medio de expresión innovador, Daniel Bilbao hace gala de su conocimiento en esta práctica tan trascendental que marcó un antes y un después, de una buena dosis de creatividad, utilizando para ello formatos pequeños e iguales para todas sus composiciones lo cual le permite un trabajo más concentrado en su labor de recortar y pegar, obteniendo unos resultados de gran estima plástica y visual

Is plastidic glutamine synthetase essential for C-3 plants? A tale of photorespiratory mutants, ammonium tolerance and conifers

[EN] Agriculture faces the considerable challenge of having to adapt to a progressively changing climate (including the increase in CO2 levels and temperatures); environmental impact must be reduced while at the same time crop yields need to be maintained or increased to ensure food security. Under this scenario, increasing plants' nitrogen (N) use efficiency and minimizing the energy losses associated with photorespiration are two goals of crop breeding that are long sought after. The plastidic glutamine synthetase (GS2) enzyme stands at the crossroads of N assimilation and photorespiration, and is therefore a key candidate for the improvement of crop performance. The GS2 enzyme has long been considered essential for angiosperm survival under photorespiratory conditions. Surprisingly, in Arabidopsis GS2 is not essential for plant survival, and its absence confers tolerance towards ammonium stress, which is in conflict with the idea that NH4+ accumulation is one of the main causes of ammonium stress. Altogether, it appears that the 'textbook' view of this enzyme must be revisited, especially regarding the degree to which it is essential for plant growth under photorespiratory conditions, and the role of NH4+ assimilation during ammonium stress. In this article we open the debate on whether more or less GS2 is a desirable trait for plant productivity.This research was funded by the Basque Government (IT932-16), the Spanish State Research Agency (AEI) (PID2020-113385RB-I00 and RTI2018-093571-B-100 co-funded by FEDER, EU), Junta de Andalucia (P20_00036 PAIDI 2020/FEDER, UE) and the project US-1256179 grant from Junta de Andalucia, FEDER and Universidad de Sevilla

Undirected dependency parsing

Dependency parsers, which are widely used in natural language processing tasks, employ a representation of syntax in which the structure of sentences is expressed in the form of directed links (dependencies) between their words. In this article, we introduce a new approach to transition-based dependency parsing in which the parsing algorithm does not directly construct dependencies, but rather undirected links, which are then assigned a direction in a postprocessing step. We show that this alleviates error propagation, because undirected parsers do not need to observe the single-head constraint, resulting in better accuracy. Undirected parsers can be obtained by transforming existing directed transition-based parsers as long as they satisfy certain conditions. We apply this approach to obtain undirected variants of three different parsers (the Planar, 2-Planar, and Covington algorithms) and perform experiments on several data sets from the CoNLL-X shared tasks and on the Wall Street Journal portion of the Penn Treebank, showing that our approach is successful in reducing error propagation and produces improvements in parsing accuracy in most of the cases and achieving results competitive with state-of-the-art transition-based parsers.Xunta de Galicia | Ref. CN2012/008Xunta de Galicia | Ref. CN2012/317Xunta de Galicia | Ref. CN2012/319Ministerio de Ciencia e Innovación | Ref. TIN2010-18552-C03-01Ministerio de Ciencia e Innovación | Ref. TIN2010-18552-C03-0

¿Estuvo Colón en el Canadá?

"Yo navegué en el año de 1477, en el mes de febrero, 100 leguas más allá de la isla Tile (Ultra Tile o Thule) cuya parte sur está ubicada a setenta y tres grados de distancia del círculo equinoccial, y no sesenta y tres como alguien dijo, y no está dentro de la línea que delimita el poniente, como dijo Tolomeo, pero más lejos hacia occidente y desde esta isla, que es tan grande como Inglaterra, van los ingleses con sus mercaderías, especialmente aquellos de Bristol, y cuando yo estuve allí el mar no estaba helado, aunque había mareas tan altas que en algunos sitios subían y bajaban dos veces diariamente veintiseis brazas"

Artificial wood boards as new grounds of drawing and pictorial processes (Aglomerado, Contrachapado, DM, Tablex)

En contradicción con el auge que los nuevos elementos y técnicas adquieren dentro de las artes plásticas, existe una desinformación generalizada sobre la mayona de los mismos, que se traduce en el uso sin criterio racional y, por tanto, discutible capacidad para el aprovechamiento de todos los beneficios potenciales que en ellos se encuentran. El objetivo de esta investigación se centra en los tableros de madera artificial (compuestos por fibras y virutas de madera, aglutinados con resinas sintéticas) como nuevos soportes de la obra plástica desarrollando sobre ellos diversos procedimientos dibujísticos y pictóricos y diversas formas de preparación de la base, se obtienen resultados variados y se establecen relaciones soporte-técnica para poder obtener el máximo potencial expresivo en cada caso. Con esta investigación se intentan lograr dos objetivos: a.- Ayudar a los profesionales a saber seleccionar la capacidad del soporte de madera, en función del tipo de preparación y la técnica que se desarrollará sobre la superficie. b.- Obtener un trabajo experimental que sirva de guía para una mejor formación de los alumnos en las facultades de Bellas Artes. El término madera artificial El término Madera Artificial no aparece establecido oficiosamente en ninguna fuente de información de las que se han consultado durante la realización de este trabajo, ante este vacío léxico y a la vista de la investigación me permito plantear una definición: a toda aquella madera que extraída de una fuente natural, sufre una alteración de tipo químico y mecánico en su constitución definitiva.In contradiction with the increasing succes of the new materials and techniques within the plastic arts there is a general lack of information about most of them which has led to their utilization whitout rational criterions and a doubtful capability to takeadvantage of all the potential profits which can be found in them. The object of this research work is based on artificial wood boards (composed of wood flake and fibres joined together with synthetic resins) as the new resources for the plastic works. Developing over them different drawing and pictorial processes and different ways of setting the ground of the boards, it is possible to archieve assorted results as well as it establishes a relationship between support and technique that allows to obtain the maximun of the potential expression in each case. Two targets have been sought with this investigation:- Helping professionals to know how to choose the quality of the board, depending on the different ways of preparing it and the technique to developed on its surface. - Achieving an experimental product which may serve as a guide for the better formation of Fine Arts University pupils. The term Artificial wood The term AArtificial wood is not actually described in any of the information sources consulted during the realisation of this work. Because of this lexical absence and regarding the results of the work, I dare suggest a definition: AA11 wood previously extracted from a natural source suffers a chemical and mechanical transformation in its final composition