Briefing on meetings at & reports by the 65th & 66th United Nations General Assembly

Briefing on meetings at & reports by the 65th & 66th United Nations General AssemblyNo relevant differences are observed or identified after perusal of the space-related resolutions and documents issued by the UN System between 2010 and 2011. The most remarkable statements remain virtually unchanged in this time period. For instance, the UN GA recognizes the common interest of all mankind in the exploration and use of outer space for peaceful purposes, and reaffirms that these shall be carried out for the benefit and in the interest of all countries, irrespective of their degree of development. Also, the growing use of outer space increases the need for greater transparency and better information on the part of the international community. Again in 2011, the UN GA stated that it is deeply convinced of the important role that science and technology play in promoting sustained economic growth and sustainable development and that their use and applications in areas such as telemedicine, tele-education, disaster management, environmental protection and other EO applications, contribute to achieve the objectives in various aspects of economic, social and cultural development and welfare, particularly poverty eradication and mitigation of the consequences of disasters. It is necessary to continue to examine how space science and technology and their applications could contribute to achieve the UN MDG, since space tools are indispensable not only in areas linked to disasters, but also in climate change, food security, opportunities for education and global health. In 2011, 12 April was declared as the International Day of Human Space Flight to celebrate each year at the international level the beginning of the space era for mankind, reaffirming the important contribution of space science and technology in achieving sustainable development goals and increasing the well-being of States and peoples, as well as ensuring the realization of their aspiration to maintain outer space for peaceful purposes. We congratulate SGAC people working on the project YGNSS as their contribution [8] to the 2011 HLS AMR of the UN ECOSOC was accepted for distribution to all participants of the HLS in Geneva, July 2011. In this a written statement, the YNSS team informed the HLS AMR that SGAC “is focused on cultivating the next generation of space leaders and increasing awareness of the educational and societal benefits of space technology” and that “Within SGAC, the project YGNSS aims to present to youth the benefits of GNSS and how various such systems applications are able to benefit a nation’s economy and society”. Also, it is mentioned that “YGNSS has supported the educational outreach of GNSS applications”, that YGNSS has spread “the word that GNSS can be used for precision timing, agricultural and disaster management, and a wide variety of items that need accurate positioning, navigation, and timing”, that YGNSS has recommended “that the international community continue to foster the education of GNSS and the utilities of space technology”. Finally, the written statement informs that SGAC “is committed to providing a network for university students and young professionals in the international space sector to collaborate and contribute their international knowledge and skills to foster development”. As per the report from the IAF GEOSS Workshop, Space Sensors for Climate Monitoring [9], it is worth noting that satellite data are required to effectively monitor, characterize and predict changes in the Earth system, and particularly in the climate. Earth Observation (EO) satellites are essential as they provide the only realistic means to obtain the necessary global coverage. With well-calibrated measurements, e.g. using in situ data, space-based sensors will become a critical contribution to global observations for climate.Preprin

Estudio sobre emplazamiento de edificio túnel de viento en el Aeródromo de Empuriabrava

Estudio sobre emplazamiento de edificio túnel de viento en el Aeródromo de EmpuriabravaEstudio sobre emplazamiento de edificio túnel de viento en el Aeródromo de EmpuriabravaSkydair Empuriabrava SL tiene en proyecto la construcción de un edificio túnel de viento y construcciones auxiliares en el Aeródromo de Empuriabrava (Castelló d’Empúries, Alt Empordà). El proyecto prevé que dicho edificio y construcciones auxiliares estén ubicados en terrenos afectados por las servidumbres aeronáuticas del aeródromo, luego es imprescindible solicitar la autorización de la DGAC para su construcción. Tras un estudio aeronáutico, se ha determinado que tanto el edificio túnel de viento como sus construcciones auxiliares no invaden las superficies delimitadoras de obstáculos que aplican para el Aeródromo de Empuriabrava, en concordancia con la normativa y recomendaciones vigentes del Anexo 14 de OACI y el Decreto 584/1972, de 24 de febrero. En particular, el estudio ha permitido verificar que el edificio y construcciones auxiliares no sobresalen de las servidumbres aeronáuticas para dos supuestos: el escenario 1, en el que se considera que la clave de referencia OACI del Aeródromo de Empuriabrava es 1C, y el escenario 2, en el que las servidumbres que aplican se corresponden con las definidas por OACI para un aeródromo de número de clave 3. El estudio concluye por tanto que el edificio y construcciones auxiliares no constituyen obstáculos en ninguno de los dos escenarios. Mención aparte merece el caso del mástil para renovación de aire. En la fase presente (enero de 2008) del proyecto, falta por concretarse la altura del mástil para renovación de aire (una de las construcciones auxiliares del edificio). En el diseño final, se deberá imponer un límite adecuado en altura para el mástil con objeto de que el mismo no sobresalga, sobretodo, de la superficie de transición definida para el escenario 1, ni de la definida para el escenario 2, si ello fuera posible (atendiendo a los otros parámetros de diseño: los requerimientos de renovación de aire y de aislamiento acústico del edificio), puesto que es más restrictiva. Aun en el caso que el mástil no sobresalga de la superficie de transición 2, se recomienda señalizarlo por considerar que se trata de un punto elevado próximo a una servidumbre aeronáutica. Atendiendo a lo especificado por OACI en su Anexo 14, el mástil debería señalarse con bandas de color alternas (blanco y rojo), perpendiculares a la dimensión mayor del mástil, y tener un ancho igual a 1/7 de esta dimensión mayor. Las bandas de los extremos del mástil deberían ser del color más oscuro (el rojo). Por otro lado, el Aeródromo de Empuriabrava no está preparado para la operación de aeronaves por la noche, por lo que en ningún caso se considera necesario iluminar el mástil.Postprint (published version

Informe técnico de compatibilidad aeronáutica de una antena de telefonía en las inmediaciones del Aeropuerto de Sabadell

Informe técnico de compatibilidad aeronáutica de una antena de telefonía en las inmediaciones del Aeropuerto de SabadellInforme técnico de compatibilidad aeronáutica de una antena de telefonía en las inmediaciones del Aeropuerto de SabadellLa presencia de un aeródromo en las proximidades del municipio de Sabadell condiciona cualquier proyecto y edificación que supere cierta altura respecto a la elevación del propio aeropuerto. Esta restricción de alturas viene ligada a la presencia de un conjunto de servidumbres físicas definidas entorno al aeropuerto, cuya finalidad es asegurar un nivel mínimo de seguridad en la operación aérea de las aeronaves. Adicionalmente existen una serie de servidumbres operacionales y radioeléctricas que también deben respetarse, aunque por lo general son menos restrictivas que las servidumbres físicas (superficies limitadoras de obstáculos). Dada la orografía del terreno en los alrededores del Aeropuerto de Sabadell, las superficies limitadoras de obstáculos se proyectan sobre gran parte de la ciudad y de zonas urbanizadas cercanas. El terreno es ascendente hacia la parte septentrional (hacia el centro de Sabadell) y a mayor distancia, es descendente y posteriormente ascendente hacia ambos lados del aeropuerto (hacia las localidades de Bellaterra y Sabadell, respectivamente). Por ello es habitual que tanto el terreno como las edificaciones cercanas interaccionen con alguna de las superficies limitadoras de obstáculos del aeropuerto. La antena objeto del presente informe está instalada la calle Pin i Soler s/n, próxima a la carretera BV-1414 de la localidad de Bellaterra, en una parcela en la que también se encuentran emplazadas un conjunto de otras 3 antenas de características y alturas similares. El objetivo de este informe será tratar de demostrar que esta antena de telefonía no afecta a la seguridad de las operaciones ni a la propia actividad aérea del Aeropuerto de Sabadell.Postprint (published version

Certification of UN heliports for night operations

Certification of UN heliports for night operationsFor strategic reasons, it is very important to increase the number of heliports certified for UN helicopter operations, as this enhances the efficiency of the UN Peacekeeping Missions. For instance, increased availability of certified heliports over a wider area on the field would enable improvements of the management of UN resources and the air transport activities. In particular, for the case of casualty evacuation (CASEVAC) involving injured military or civilian personnel where a threat to life or limb exists, or medical evacuations (MEDEVAC) of patients, a wider network of heliports is paramount, because it enables much faster and painless transfers of personnel to the first available levels of medical care. Hence, the chances of saving the lives of injured or seriously ill persons increase significantly. In any case, the heliports must meet critical requirements so essentially it is guaranteed the safety of the operations.Peer ReviewedPreprin

Exercises for Infraestructura del transporte aéreo (ITA)

2011/201

Study on Mechanical Relaxations of 7075 (Al–Zn–Mg) and 2024 (Al–Cu–Mg) Alloys by Application of the Time-Temperature Superposition Principle

The viscoelastic response of commercial Al–Zn–Mg and Al–Cu–Mg alloys was measured with a dynamic-mechanical analyzer (DMA) as a function of the temperature (from 30 to 425ºC) and the loading frequency (from 0.01 to 150 Hz). The time-temperature superposition (TTS) principle has proven to be useful in studying mechanical relaxations and obtaining master curves for amorphous materials. In this work, the TTS principle is applied to the measured viscoelastic data (i.e., the storage and loss moduli) to obtain the corresponding master curves, and to analyze the mechanical relaxations responsible for the viscoelastic behavior of the studied alloys. For the storage modulus it was possible to identify a master curve for a low-temperature region (from room temperature to 150ºC) and, for the storage and loss moduli, another master curve for a high-temperature region (from 320 to 375ºC). These temperature regions are coincidental with the stable intervals where no phase transformations occur. The different temperature dependencies of the shift factors for the identified master curves, manifested by different values of the activation energy in the Arrhenius expressions for the shift factor, are due to the occurrence of microstructural changes and variations in the relaxation mechanisms between the mentioned temperature regions.Peer ReviewedPostprint (published version

The potential of the sea breeze for wind energy generation in peri-urban coastal areas using small wind turbines

This work investigates the potential of the sea breeze for wind energy generation with small wind turbines. For this purpose, we used wind data recorded in the Llobregat Delta (NE of the Iberian Peninsula) from 1993 to 2010 and turbine power curves obtained from QBlade, FAST and AeroDyn freeware tools, and from the manufacturer. The HP-600W turbine, with hub-height 8 m, would deliver 126 kWh in a year (53 kWh during the sea breeze period, i.e., March 1 to September 30, 10 to 19h LT), with average power of 14 W (27 W). The results for the entire year agree with data measured in situ in 2015, but it is not the case for the sea breeze period. Therefore, more research is necessary to validate completely the proposed approach, and to confirm the real potential of the sea breeze for micro-generation in a peri-urban coastal area like the one under study, where large wind farms are not feasible.Peer ReviewedPostprint (author's final draft

Development of a Low-Cost Weather Station to Measure in Situ Essential Climate Variables

A weather station is proposed especially designed for developing countries, and to meet the standards of the international scientific community making research on the earth system. The station would measure in situ several ECV (essential climate variables). These data may enable an agricultural breakthrough in countries lacking meteorological infrastructure, help in climate change monitoring, and facilitate diffusion of wind energy. A pre-feasibility analysis is presented. It appears interesting that the station is supplied by a social enterprise. A research to establish the best shelter design using computational fluid dynamics is also reported. The criterion is the accuracy with which the surface air temperature is reproduced inside the shelter. A design following recommendations by the WMO (World Meteorological Organization), a smaller design with identical geometry, and two alternative small designs are analyzed. All four designs are simulated in PVC, natural rubber and wood, with and without white paint coating. The smaller shelters perform better. The influence of the material, dimensions and design is smaller than that of the white paint. Shelters made of PVC or rubber, and/or in alternative designs, may be more interesting if other criteria are considered, like whether logistics, manufacturing, etc. are more sustainable, easier and/or cheaper.Peer ReviewedPostprint (published version

Compendium of procedures: tècniques experimentals en aerofísica (TEA)

2011/201

Modeling of the effect of temperature, frequency, and phase transformations on the viscoelastic properties of AA 7075-T6 and AA 2024-T3 Aluminum Alloys

The viscoelastic response of commercial aluminum alloys 7075-T6 and 2024-T3 as a function of temperature is presented. Experimental data are obtained with a dynamic-mechanical analyzer (DMA) at different loading frequencies and compared with the available transmission electron microscopy (TEM) and differential scanning calorimetry (DSC) data. The effect of successive microstructural transformations (particle precipitation and redissolution) is revealed. An ana- lytical model is developed, which fits the mechanical response up to 573 K (300 C). The model takes into account the concentration of Guinier-Preston Zones (GPZ) and metastable precipi- tates ( g ¢ in AA 7075-T6 and h ¢ /S ¢ in AA 2024-T3), allowing us to determine the kinetic parameters of these transformations. The activation energies were previously obtained by sev- eral authors from DSC measurements and other techniques, showing considerable dispersion. The presented data, obtained with a completely different technique, allow us to reduce the uncertainty on these data and show the potential of DMA measurements in the study of microstructural transformations.Peer ReviewedPostprint (published version