377 research outputs found
The transition of food consumption towards sustainable patterns based on environmental, economic and nutritional aspects
É máis urxente que nunca acadar un sistema alimentario sostible que sexa
respectuoso co medio ambiente, que ofreza seguridade e calidade alimentaria a toda a poboación mundial e, ao
mesmo tempo, sexa social e economicamente aceptable. Para iso, os cambios nos patróns alimentarios actuais
son unha das ferramentas máis poderosas e eficaces. A adhesión ás dietas tradicionais, baseadas principalmente
no consumo de produtos de orixe vexetal e o consumo limitado de produtos de orixe animal e ultra-procesados,
considérase como a pedra angular para acadar este obxectivo. AsÃ, esta tese ten como principal finalidade analizar
diferentes patróns de consumo de alimentos desde o punto de vista ambiental, nutricional e socioeconómico, e
propoñer as medidas axeitadas para lograr patróns dietéticos más sostibles. Ademais, o proceso de produción de
alimentos tamén se analiza en profundidade mediante a análise do ciclo de vida de produtos agro-alimentarios
relevantes
FenologÃa y crecimiento de Pinus uncinata y Pinus sylvestris en los Pirineos Centrales en el Periodo 1997-2000
Evaluation of separation strategies for unmanned aerial sytems
This paper analyzes loss of separation scenarios when an Unmanned Aircraft (UA) enters in conflict with a much faster airplane flying at the same altitude. Separation distances are analyzed in terms of minimum heading changes and reaction times. Results show that maneuvers need to be
performed well in advance if the (low-speed) UA is the aircraft that changes its heading. In some cases the time in which the UA and the intruder are in conflict could be too long, and may even involve multiple airliners flying over the same airway. Given
that standard separation strategies may have a negative impact on the UA mission, in this paper a set of pre-planned separation
maneuvers are proposed. These maneuvers aim to improve the situational awareness of both air traffic controller and UA pilotin-
command, but also to disrupt as less as possible the mission performed by the UA and to minimize the uncertainty in the reactions the UA may adopt autonomously if the link with the ground station is lost. Some preliminary real-time simulations are shown, using a UA ground station simulator linked to a air traffic control simulator.Peer ReviewedPostprint (author’s final draft
An Assessment for UAS Traffic Awareness Operations
Technology evolution in the field of Unmanned
Aircraft Systems (UAS) will affect the Air Traffic
Management (ATM) performance regarding
to new military and civil applications. UAS, as
new airspace users, will represent new challenges
and opportunities to design the ATM system of
the future. The goal of this future ATM network
is to keep intact (or improve) the network in terms
of security, safety, capacity and efficiency level.
On the other hand, most UAS are, at present, designed
for military purposes and very few civil
applications have been developed mainly because
the lack of a regulation basis concerning their certification,
airworthiness and operations. Therefore,
UAS operations have always been solutions
highly dependent on the mission to be accomplished
and on the scenario of flight. The generalized
development of UAS applications is still
limited by the absence of systems that support
the development of the actual operations. Moreover,
the systematic development of UAS missions
leads to many other operational risks that
need to be addressed. All this elements may delay,
increase the risk and cost in the implementation
of a new UAS application.Peer ReviewedPostprint (published version
Study of seawater biofiltration by measuring adenosine triphosphate (ATP) and turbidity
In the present study, we examined seawater biofiltration in terms of adenosine triphosphate (ATP) and turbidity. A pilot biofilter continuously fed with fresh seawater reduced both turbidity and biological activity measured by ATP. Experiments operated with an empty bed contact time (EBCT) of between 2 and 14 min resulted in cellular ATP removals of 32% to 60% and turbidity removals of 38% to 75%. Analysis of the water from backwashing the biofilter revealed that the first half of the biofilter concentrated around 80% of the active biomass and colloidal material that produces turbidity. By reducing the EBCT, the biological activity moved from the first part of the biofilter to the end. Balances of cellular ATP and turbidity between consecutive backwashings indicated that the biological activity generated in the biofilter represented more than 90% of the detached cellular ATP. In contrast, the trapped ATP was less than 10% of the overall cellular ATP detached during the backwashing process. Furthermore, the biological activity generated in the biofilter seemed to be more dependent on the elapsed time than the volume filtered. In contrast, the turbidity trapped in the biofilter was proportional to the volume filtered, although a slightly higher amount of turbidity was found in the backwashing water; this was probably due to attrition of the bed medium. Finally, no correlations were found between turbidity and ATP, indicating that the two parameters focus on different matter. This suggests that turbidity should not be used as an alternative to cellular concentration
La gimnástica o escuela de la juventud (1807) : primer libro de educación fÃsica escolar y génesis de un discurso pedagógico
A partir del primer libro que llegó a España de Educación FÃsica La gimnástica o escuela de la juventud (1807), traducción de la versión francesa realizada en 1803 por A. Amar Durivier y L. F. Jauffret, se presenta un análisis de contenido deconstructivo para reconocer el discurso ideológico sobre el que descansa. Para ello se usa una metodologÃa basada en el análisis crÃtico del discurso con el soporte de otros textos de la época, además de la revisión de diferentes estudios que articulan la construcción del contexto teórico. Al final del estudio se realiza un análisis crÃtico de los contenidos del libro comparándolos con los actuales de la Educación FÃsica. Todo indica que, tras el paso del tiempo, siguen prevaleciendo los mismos contenidos y que los modos de educación tampoco han cambiado tantoFrom the first book on Physical Education to arrive in Spain, La gimnástica o escuela de la juventud (1807), translated from the French version written in 1803 by A. Amar Durivier and L. F. Jauffret, this article presents an analsis of the deconstructive content in order to recognise the ideological discourse on which it rests. We use a methodology based on critical analysis of the discourse supported by other texts from the same period as werll as reviews of different studies articulating the construction of the theoretical context. At the end of the study there is a critical analysis of the content of the book with current books on Physical Education. Everything seems to indicate that over time the same content is still prevalent and that the educational methods have not changed substantially eithe
Entorno de simulación basado en agentes para A-CDM (Airport Collaborative Decision Making)
Due to the increased air traffic in Europe, airports have to handle traffic volumes near to its maximum capacity. This makes it mandatory to take measures to improve the efficiency and capacity of airports. To improve the capacity of airports, the different actors in them must communicate with each other in order to improve the way they manage the traffic. Airport Collaborative Decision Making (A-CDM) is based on information sharing. A better use of resources can be attained when the different stakeholders at airport operations share their more accurate and updated information. One of the main difficulties when dealing with this information sharing concept is the number of stakeholders involved and their different interest and behaviour: aircraft operators, ground handling companies, airport authority, air traffic control and the Central Flow Management Unit. It is paramount to quantify the benefit of an airport collaborative decision making strategy in order to involve all these different organisations. Simulations are required to analyse the overall system and its emerging behaviour. This project presents the development and initial testing of an agent-based framework, which allows this behavioural analysis to be done. The simulator explicitly represents the different stakeholders involved in the A-CDM and the interactions between them during the 16 milestones defined by EUROCONTROL on its A-CDM implementation manual, also different functionalities have been implemented to add realism to the simulations, such as the possibility to add delays and adverse conditions to the air traffic and to analyse the different results of the different simulations. This framework allows independent gradual development of local behaviours and optimisation, and a gradual increase on complexity and fidelity on the simulations
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