Collaborative Engineering: An Airbus Case Study

AbstractThis document introduces the main concepts of Collaborative Engineering as a new methodology, procedures and tools to design and develop an aircraft, as Airbus Military is implementing.Airbus designs and industrializes aircrafts under Concurrent Engineering techniques since decades with success. The introduction of new PLM methodologies, procedures and tools, mainly in the industrialization areas, and the need to reduce time-to-market conducted Airbus Military to push the engineering teams to do things in a different way.Traditional Engineering works sequentially, Concurrent Engineering basically overlaps tasks between teams using maturity states and taking assuming risks. Collaborative Engineering promotes a single team to develop product, processes and resources from the conceptual phase to the start of the serial production. The deliverable of the team is an iDMU (industrial DMU), a complete definition and verification of the virtual manufacturing of the product

Implementation of the iDMU for an Aerostructure Industrialization in AIRBUS

AbstractAIRBUS Military has undertaken a project to implement the industrial Digital Mock-Up (iDMU) concept to support the industrialization process of a medium size aerostructure. Within the framework of a collaborative engineering strategy, such project is part of the efforts to deploy Digital Manufacturing as a key technology for the industrialization of aircrafts assembly lines. The project has confirmed the potential of the iDMU to improve the industrial design process in a collaborative engineering environment. This communication presents the main project objectives, the key methodological points, the main project achievements and the next additional developments to increase the scope and benefits of the iDMU concept

Separation and measurement of Pa, Th, and U isotopes in Marine sediments by microwave-assisted digestion and multiple collector inductively coupled plasma mass spectrometry

This manuscript describes a new protocol for determination of Pa/Th/U in marine sediments. It is based on microwave-assisted digestion and represents an important reduction of working time over conventional hot-plate digestion methods, and the use of HClO(4) is avoided. Although Th and U are completely dissolved with a first microwave step, around 40% of (231)Pa remains undissolved, and a short hot-plate step with reverse aqua regia is required to achieve total digestion and spike equilibration. Next, the method involves a separation of these elements and a further purification of the Pa fraction using Dowex AG1-X8 resin. Separation with Bio-Rad and Sigma-Aldrich resins was compared; although both perform similarly for Th and U, Pa yields are higher with Bio-Rad. Finally, samples are measured using a Nu instruments multiple collector inductively coupled plasma mass spectrometer (MC-ICPMS). Overall chemical yields range around 50% for Pa, 60% for Th, and 70% for U

Estrategias marinas: Evaluación inicial, buen estado ambiental y objetivos ambientales

El documento marco de las estrategias marinas es el marco general introductorio de los documentos que constituyen las primeras fases de las cinco estrategias marinas españolas. En el año 2012 el entonces Ministerio de Agricultura, Alimentación y Medio Ambiente preparó para cada una de las cinco demarcaciones marinas de España un documento de evaluación inicial, definición de buen estado ambiental y establecimiento de objetivos ambientales, que son las primeras fases en la elaboración de las estrategias marinas. A pesar de las particularidades de cada una de las demarcaciones marinas, existen elementos comunes a las estrategias marinas, que se han recogido en este documento marco.Versión del edito

On String Theory Duals of Lifshitz-like Fixed Points

We present type IIB supergravity solutions which are expected to be dual to certain Lifshitz-like fixed points with anisotropic scale invariance. They are expected to describe a class of D3-D7 systems and their finite temperature generalizations are straightforward. We show that there exist solutions that interpolate between these anisotropic solutions in the IR and the standard AdS5 solutions in the UV. This predicts anisotropic RG flows from familiar isotropic fixed points to anisotropic ones. In our case, these RG flows are triggered by a non-zero theta-angle in Yang-Mills theories that linearly depends on one of the spatial coordinates. We study the perturbations around these backgrounds and discuss the possibility of instability. We also holographically compute their thermal entropies, viscosities, and entanglement entropies.Comment: 47 pages, 4 figure

Laser-driven direct synthesis of carbon nanodots and application as sensitizers for visible-light photocatalysis

We present the first successful synthesis of monodisperse carbon nanodots (CNDs) with tunable photoluminescence (PL) carried out by laser pyrolysis of two common volatile organic precursors such as toluene and pyridine. Remarkably, the initial chemical composition of the precursor determines the formation of undoped or N-doped CNDs and their corresponding absorption response in the visible range (expanded for the latter). We demonstrate the control and versatility of this synthesis method to tune the final outcome and its potential to explore a great number of potential solvent candidates. Furthermore, we have successfully exploited these CNDs (both undoped and N-doped) as effective sensitizers of TiO2 nanoparticles in the visible-light driven photo-degradation of a cationic dye selected as model organic pollutant

Attention to Wi-Fi Diversity: Resource Management in WLANs with Heterogeneous APs

Many home networks integrate a small number (typically 2-4) of Wi-Fi Access Points (APs), with heterogeneous characteristics: different 802.11 variants, capabilities and security schemes. This paper proposes the consideration of these specific characteristics in order to improve the management of network resources. Three use cases are presented in order to showcase the potential benefits. By the use of a user-space AP, which works in coordination with a controller, the network is able to assign each connected station to the AP that best fits with its characteristics. The system also manages security, avoiding the need of adding specific elements for authentication, encryption or decryption. Extensions are proposed to an existing protocol that defines the communication between the AP and the controller, in order to communicate and store the specific characteristics of each AP and end device. This includes new association and handoff schemes that do not introduce any additional delay. The system has been implemented in a real environment, and a battery of tests has been run using three hardware platforms of different characteristics. The results show that handoffs between bands are possible, and estimate the processing delays, the Round-Trip Time and the handoff delay, which is small enough in order not to produce any significant disruption to the user (10-50 ms). Finally, the scenarios of interest have been replicated in a simulation environment, showing that significant benefits can be achieved if the specific characteristics of each AP and station are considered

Continental shelf zones influenced by the suspended matter flows coming from Cadiz Bay

Due to the diversity of environments and hydrodynamics in Cadiz Bay, it is of interest to study the dynamics of sedimentary exchange between the coastal zones and continental shelf. The most abundant clay minerals on the floor of the continental shelf and Cadiz Bay, and in the particulate matter in suspension, are: illite, smectite, kaolinite + chlorite, and the interstratified clay minerals illite-smectite. The average concentration of suspended matter is 6.5 mg/l, the lowest (1.37 mg/l) being found on the inner shelf and in the inner zones of the bay less affected by currents and surge. The highest values (14 mg/l) are found in the outer bay, consistent with the distribution of muddy facies on the sea floor. The flow paths have been established from the local variations in the mineralogical associations found at the sampling stations, and by means of the alignments of the lowest values of the factor loadings at those stations most affected by the flows. The mineralogical similarity of the components of the clay fraction is related to the mixing action undergone by the components of the suspended matter reaching the bay from various sources, probably produced by the continuous action of the tidal ebb currents flowing from the inner sectors of the bay towards the continental shelf.El estudio de la dinámica de intercambio sedimentario entre las zonas litorales y la plataforma continental es de gran interés en el caso de la bahía de Cádiz, debido a su diversidad de ambientes y situaciones hidrodinámicas. Los minerales de la arcilla más abundantes en los fondos de la plataforma y la bahía, y en la materia en suspensión, son ilita, esmectita, caolinita + clorita e interestratificados ilita-esmectita. La concentración de materia sólida en suspensión indica un contenido promedio de 6,5 mg/l, apareciendo los mínimos (1,37 mg/l) en la plataforma interna y en zonas internas de la bahía no afectadas por corrientes y oleaje. Los valores más altos se dan en la bahía externa (14 mg/l), de acuerdo con la distribución de facies fangosas en el fondo. Las trayectorias de los flujos salientes se han establecido a partir de las variaciones locales de las asociaciones mineralógicas en las diferentes estaciones de muestreo, alineándose los valores más bajos de los factores en las estaciones más afectadas por la acción de los flujos. La similitud mineralógica de los componentes de la fracción arcilla en todos los ambientes se debe a la mezcla de componentes de la materia en suspensión que, desde diferentes fuentes, llegan a la bahía, y es favorecida por la acción de la corriente de reflujo mareal desde el sector más interno de la bahía a la plataforma continental.Instituto Español de Oceanografí

Searching for biomarkers of aneurysmal disease

Comunicaciones a congreso