84 research outputs found

    Preliminary and advanced structural design of a three-modal camber morphing wing flap for large civil aircraft applications

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    Researchers and engineers design modern aircraft wings to reach high levels of efficiency with the main outcome of weight saving and airplane lift-to-drag ratio increasing. Future commercial aircraft need to be mission-adaptive to improve their operational efficiency. Within the framework of Clean Sky 2 Airgreen 2 (REG-IADP) European research project, a novel multifunctional morphing flap technology was investigated to improve the aerodynamic performances of the next Turboprop regional aircraft (90 passengers) along its flight mission. The proposed true-scale device (5 meters span with a mean chord of 0.6 meters) is conceived to replace and enhance conventional Fowler flap with new functionalities. Three different functions were enabled: overall airfoil camber morphing up to +28 deg (mode 1), +/- 10 deg (upwards/downwards) deflections of the flap tip segment (mode 2), flap tip twist of +/- 5 deg along the outer flap span (mode 3). Morphing mode 1 is supposed to be activated during take-off and landing only to enhance aircraft high-lift performances and steeper initial climb and descent. Thanks to this function, more airfoil shapes are available at each flap setting and therefore a dramatic simplification of the flap deployment system may be implemented. Morphing modes 2 and 3 are enabled in cruise and off-design flight conditions to improve wing aerodynamic efficiency. The proposed structural concept consists of a multi-box arrangement activated by segmented ribs with embedded inner mechanisms to realize the transition from the baseline configuration to different target aero-shapes while withstanding the aerodynamic loads. Lightweight and compact actuating leverages driven by electromechanical motors were properly integrated to comply with demanding requirements for real aircraft implementation: minimum actuating torque, minimum number of motors, reduced weight, and available design space. The methodology for the design of the inner mechanisms is based on a building block approach where the instant centres analysis tool is used to preliminary select the locations of the hinges’ leverages. The structural layout of an Adaptive Twist composite Tab was considered as a promising concept to balance the conflicting requirements between load-carrying capability and shape adaptivity in morphing lightweight structures. Finally, the embedded system functionality of the actuation system coupled with the structural skeleton is fully investigated by means of detailed finite element simulations. Results of actuation system performances, and aeroelastic deformations considering limit aerodynamic loads demonstrate the potential of the proposed structural concepts to be energy efficient, and lightweight for real aircraft implementation

    Development of a long range wireless sensor platform

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    Wireless Sensor Networks have emerged as an exciting field in recent years. There have been numerous studies on how to improve and standardise different aspects of wireless sensor networks. This paper aims to develop a wireless sensor network suitable for environmental monitoring applications. More specifically this paper aims to address the limited communication range of the existing wireless sensor technology. In order to achieve the desired objectives, we have initially developed a hardware platform and then integrated the hardware with a long range RF radio module to achieve the goals. The system is further enhanced with mesh networking capabilities to increase the communication range and overall reliability of the network. The developed wireless sensor network is composed of sensors, microcontroller, RF radio module, antenna and expansion connectors for additional sensors and peripheral devices. The developed wireless sensor network has been rigorously tested under three different scenarios to ensure the correct operation of the mesh network, communication range and effect of environmental obstacles such as vegetation and trees. The developed wireless sensor network has been proven to be a suitable platform for environmental monitoring applications and the modular design has made it very easy to optimise it for different applications

    Integrating renewable energy resources into the smart grid: recent developments in information and communication technologies

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    Rising energy costs, losses in the present-day electricity grid, risks from nuclear power generation, and global environmental changes are motivating a transformation of the conventional ways of generating electricity. Globally, there is a desire to rely more on renewable energy resources (RERs) for electricity generation. RERs reduce green house gas emissions and may have economic benefits, e.g., through applying demand side management with dynamic pricing so as to shift loads from fossil fuel-based generators to RERs. The electricity grid is presently evolving towards an intelligent grid, the so-called smart grid (SG). One of the major goals of the future SG is to move towards 100% electricity generation from RERs, i.e., towards a 100% renewable grid. However, the disparate, intermittent, and typically widely geographically distributed nature of RERs complicates the integration of RERs into the SG. Moreover, individual RERs have generally lower capacity than conventional fossil-fuel plants, and these RERs are based on a wide spectrum of different technologies. In this article, we give an overview of recent efforts that aim to integrate RERs into the SG. We outline the integration of RERs into the SG along with their supporting communication networks. We also discuss ongoing projects that seek to integrate RERs into the SG around the globe. Finally, we outline future research directions on integrating RERs into the SG

    Técnicas de altas prestaciones aplicadas al diseño de infraestructuras ferroviarias complejas

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    In this work we will focus on overhead air switches design problem. The design of railway infrastructures is an important problem in the railway world, non-optimal designs cause limitations in the train speed and, most important, malfunctions and breakages. Most railway companies have regulations for the design of these elements. Those regulations have been defined by the experience, but, as far as we know, there are no computerized software tools that assist with the task of designing and testing optimal solutions for overhead switches. The aim of this thesis is the design, implementation, and evaluation of a simulator that that facilitates the exploration of all possible solutions space, looking for the set of optimal solutions in the shortest time and at the lowest possible cost. Simulators are frequently used in the world of rail infrastructure. Many of them only focus on simulated scenarios predefined by the users, analyzing the feasibility or otherwise of the proposed design. Throughout this thesis, we will propose a framework to design a complete simulator that be able to propose, simulate and evaluate multiple solutions. This framework is based on four pillars: compromise between simulation accuracy and complexity, automatic generation of possible solutions (automatic exploration of the solution space), consideration of all the actors involved in the design process (standards, additional restrictions, etc.), and finally, the expert’s knowledge and integration of optimization metrics. Once we defined the framework different deployment proposes are presented, one to be run in a single node, and one in a distributed system. In the first paradigm, one thread per CPU available in the system is launched. All the simulators are designed around this paradigm of parallelism. The second simulation approach will be designed to be deploy in a cluster with several nodes, MPI will be used for that purpose. Finally, after the implementation of each of the approaches, we will proceed to evaluate the performance of each of them, carrying out a comparison of time and cost. Two examples of real scenarios will be used.El diseño de agujas aéreas es un problema bastante complejo y critico dentro del proceso de diseño de sistemas ferroviarios. Un diseño no óptimo puede provocar limitaciones en el servicio, como menor velocidad de tránsito, y lo que es más importante, puede ser la causa principal de accidentes y averías. La mayoría de las compañías ferroviarias disponen de regulaciones para el diseño correcto de estas agujas aéreas. Todas estas regulaciones han sido definidas bajo décadas de experiencia, pero hasta donde sé, no existen aplicaciones software que ayuden en la tarea de diseñar y probar soluciones óptimas. Es en este punto donde se centra el objetivo de la tesis, el diseño, implementación y evaluación de un simulador capaz de explorar todo el posible espacio de soluciones buscando el conjunto de soluciones óptimas en el menor tiempo y con el menor coste posible. Los simuladores son utilizados frecuentemente en el mundo de la infraestructura ferroviaria. Muchos de ellos solo se centran en la simulación de escenarios preestablecidos por el usuario, analizando la viabilidad o no del diseño propuesto. A lo largo de esta tesis, se propondrá un framework que permita al simulador final ser capaz de proponer, simular y evaluar múltiples soluciones. El framework se basa en 4 pilares fundamentales, compromiso entre precisión en la simulación y la complejidad del simulador; generación automática de posibles soluciones (exploración automática del espacio de soluciones), consideración de todos los agentes que intervienen en el proceso de diseño (normativa, restricciones adicionales, etc.) y por último, el conocimiento del experto y la integración de métricas de optimización. Una vez definido el framework se presentaran varias opciones de implementación del simulador, en la primera de ellas se diseñará e implementara una versión con hilos pura. Se lanzara un hilo por cada CPU disponible en el sistema. Todo el simulador se diseñará en torno a este paradigma de paralelismo. En un segundo simulador, se aplicará un paradigma mucho más pensado para su despliegue en un cluster y no en un único nodo (como el paradigma inicial), para ello se empleara MPI. Con esta versión se podrá adaptar el simulador al cluster en el que se va a ejecutar. Por último, se va a emplear un paradigma basado en cloud computing. Para ello, según las necesidades del escenario a simular, se emplearán más o menos máquinas virtuales. Finalmente, tras la implementación de cada uno de los simuladores, se procederá a evaluar el rendimiento de cada uno de ellos, realizando para ello una comparativa de tiempo y coste. Se empleara para ello dos ejemplos de escenarios reales.Programa Oficial de Doctorado en Ciencia y Tecnología InformáticaPresidente: José Daniel García Sánchez.- Secretario: Antonio García Dopico.- Vocal: Juan Carlos Díaz Martí

    Desarrollo de solución SD-WAN basada en SDN

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    La forma de trabajar en Internet, tanto de usuarios como de empresas, ha cambiado en los últimos años. Se está pasando de un modelo basado en proveedores de datos que residían en partes localizadas de la red a otro en el cual cualquier punto de la red puede suponer un tráfico masivo de datos. Este cambio de modelo está obligando a que los operadores comiencen a plantear soluciones escalables que soporten las tendencias futuras de tráfico en Internet. Las empresas proveedoras de Internet están buscando un modelo lo suficientemente flexible que permita por un lado, asegurar sus negocios, y por otra, soportar cambios rápidos en las redes actuales y dar cabida a las necesidades de los usuarios de forma rápida y eficiente. Actualmente, las tecnologías disponibles están dejando de ser efectivas ya que son, en su mayoría, sistemas rígidos que no tienen la suficiente capacidad para soportar las exigencias futuras de los clientes. Aquí es donde entra en escena SDN, un nuevo paradigma que cambia completamente la forma de entender las redes. Hasta ahora el despliegue de las redes estaba, en su mayoría, basado en switches, que se encargaban de encaminar todo el tráfico a partir de su propia tecnología. Con SDN, sacamos el plano de control del hardware, obteniendo un mayor manejo del acceso a la red, manteniendo el plano de datos basado en la infraestructura del switch. Además, otro punto fuerte de SDN es su alta capacidad de virtualización. Así, el modelo basado en hardware deja de ser factible, ya que cada componente requiere una configuración individual, con el fin de afrontar cambios en la red. Este cambio de filosofía viene a solucionar el problema de flexibilidad existente actualmente ya que permite tener una visión global de la red desde un punto y gestionar la red desde él a través de algoritmos más inteligentes basados en software. En este proyecto se empleará SDN, en concreto el protocolo OpenFlow para el despliegue y desarrollo de una maqueta de red virtualizada con el fin de evaluar esta tecnología.Ingeniería en Tecnologías de Telecomunicació

    An ontology framework for developing platform-independent knowledge-based engineering systems in the aerospace industry

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    This paper presents the development of a novel knowledge-based engineering (KBE) framework for implementing platform-independent knowledge-enabled product design systems within the aerospace industry. The aim of the KBE framework is to strengthen the structure, reuse and portability of knowledge consumed within KBE systems in view of supporting the cost-effective and long-term preservation of knowledge within such systems. The proposed KBE framework uses an ontology-based approach for semantic knowledge management and adopts a model-driven architecture style from the software engineering discipline. Its phases are mainly (1) Capture knowledge required for KBE system; (2) Ontology model construct of KBE system; (3) Platform-independent model (PIM) technology selection and implementation and (4) Integration of PIM KBE knowledge with computer-aided design system. A rigorous methodology is employed which is comprised of five qualitative phases namely, requirement analysis for the KBE framework, identifying software and ontological engineering elements, integration of both elements, proof of concept prototype demonstrator and finally experts validation. A case study investigating four primitive three-dimensional geometry shapes is used to quantify the applicability of the KBE framework in the aerospace industry. Additionally, experts within the aerospace and software engineering sector validated the strengths/benefits and limitations of the KBE framework. The major benefits of the developed approach are in the reduction of man-hours required for developing KBE systems within the aerospace industry and the maintainability and abstraction of the knowledge required for developing KBE systems. This approach strengthens knowledge reuse and eliminates platform-specific approaches to developing KBE systems ensuring the preservation of KBE knowledge for the long term

    Delusions of success: Costs and demand of high-speed rail in Italy and Spain

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    Mismatches between forecasted and actual costs and traffic figures are common in transport investments, especially in large scale ones, and so are delusions of the future demand. High-speed rail projects are often among the worst practices for cost overruns and demand overestimation, even where traffic figures may tell a history of apparent success. In the paper, we analyse two significant cases of delusions of success, namely the Italian and Spanish HSR programmes. The Italian one shows excellent demand performances, but is among the continent's worst cases for construction costs. The Spanish one, recognised worldwide as one of the most successful outcomes of HS policy, is the one where potential demand estimations were systematically neglected, and the planned network appears largely out-of-scale compared to actual traffic. In both cases, the forecasts were not simply biased, as well-known literature on megaproject failures has clearly shown: Italian lines were deliberately designed to increase the cost, and the Spanish network was deliberately planned out-of-scale. By means of the two cases, the paper will show that the core of the problem does not lie in the wrong estimations, but in deliberate choices of overinvestment, overdesign and overqualit

    A cloudification methodology for multidimensional analysis: Implementation and application to a railway power simulator

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    Many scientific areas make extensive use of computer simulations to study complex real-world processes. These computations are typically very resource-intensive and present scalability issues as experiments get larger even in dedicated clusters, since these are limited by their own hardware resources. Cloud computing raises as an option to move forward into the ideal unlimited scalability by providing virtually infinite resources, yet applications must be adapted to this new paradigm. This process of converting and/or migrating an application and its data in order to make use of cloud computing is sometimes known as cloudifying the application. We propose a generalist cloudification method based in the MapReduce paradigm to migrate scientific simulations into the cloud to provide greater scalability. We analysed its viability by applying it to a real-world railway power consumption simulatior and running the resulting implementation on Hadoop YARN over Amazon EC2. Our tests show that the cloudified application is highly scalable and there is still a large margin to improve the theoretical model and its implementations, and also to extend it to a wider range of simulations. We also propose and evaluate a multidimensional analysis tool based on the cloudified application. It generates, executes and evaluates several experiments in parallel, for the same simulation kernel. The results we obtained indicate that out methodology is suitable for resource intensive simulations and multidimensional analysis, as it improves infrastructure’s utilization, efficiency and scalability when running many complex experiments.This work has been partially funded under the grant TIN2013-41350-P of the Spanish Ministry of Economics and Competitiveness, and the COST Action IC1305 "Network for Sustainable Ultrascale Computing Platforms" (NESUS)

    Precision Departure Release Capability (PDRC) Technology Description

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    After takeoff, aircraft must merge into en route (Center) airspace traffic flows which may be subject to constraints that create localized demand-capacity imbalances. When demand exceeds capacity, Traffic Management Coordinators (TMCs) often use tactical departure scheduling to manage the flow of departures into the constrained Center traffic flow. Tactical departure scheduling usually involves use of a Call for Release (CFR) procedure wherein the Tower must call the Center TMC to coordinate a release time prior to allowing the flight to depart. In present-day operations release times are computed by the Center Traffic Management Advisor (TMA) decision support tool based upon manual estimates of aircraft ready time verbally communicated from the Tower to the Center. The TMA-computed release is verbally communicated from the Center back to the Tower where it is relayed to the Local controller as a release window that is typically three minutes wide. The Local controller will manage the departure to meet the coordinated release time window. Manual ready time prediction and verbal release time coordination are labor intensive and prone to inaccuracy. Also, use of release time windows adds uncertainty to the tactical departure process. Analysis of more than one million flights from January 2011 indicates that a significant number of tactically scheduled aircraft missed their en route slot due to ready time prediction uncertainty. Uncertainty in ready time estimates may result in missed opportunities to merge into constrained en route flows and lead to lost throughput. Next Generation Air Transportation System (NextGen) plans call for development of Tower automation systems capable of computing surface trajectory-based ready time estimates. NASA has developed the Precision Departure Release Capability (PDRC) concept that uses this technology to improve tactical departure scheduling by automatically communicating surface trajectory-based ready time predictions to the Center scheduling tool. The PDRC concept also incorporates earlier NASA and FAA research into automation-assisted CFR coordination. The PDRC concept helps reduce uncertainty by automatically communicating coordinated release times with seconds-level precision enabling TMCs to work with target times rather than windows. NASA has developed a PDRC prototype system that integrates the Center's TMA system with a research prototype Tower decision support tool. A two-phase field evaluation was conducted at NASA's North Texas Research Station (NTX) in Dallas-Fort Worth. The field evaluation validated the PDRC concept and demonstrated reduced release time uncertainty while being used for tactical departure scheduling of more than 230 operational flights over 29 weeks of operations. This paper presents the Technology Description. Companion papers include the Final Report and a Concept of Operations

    Optimal design and numerical analysis of a morphing flap structure

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    Over the next few years the aviation industry will face the challenge to develop a new generation of air vehicles characterised by high aerodynamic efficiency and low environmental impact. The technologies currently available, however, are inadequate to meet the demanding performance requirements and to comply with the stringent regulations in terms of polluting emissions. An innovative and very promising solution is offered by airframe morphing technologies. Morphing wing structures, internally actuated and able to change their shape smoothly to adapt to different loading conditions, would be able to achieve near-optimal lift and drag profiles throughout all the different phases of the flight. This would enhance the aircraft aerodynamic performance and contribute to a significant reduction of the fuel consumption, polluting emissions and noise. The present study has been conducted as part of the European Commission founded Seventh Framework Program called \Smart High Lift Device for the Next Generation Wing" (SADE). The aim of this research is the development of an effective design of a morphing ap with flexible trailing edge for a commercial aircraft wing. The investigation focused on morphing concepts which are suitable for large transport aircraft and which can be effectively developed and become operational within the next 20 years. For these reasons, the morphing was limited to the high lift devices of the wing, while the conventional wing box structure was retained. Cont/d
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