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In this paper, we described the Comprehensive AeroSpace Index (CASI), a financial index aimed at representing the economic performance of the aerospace industry. CASI is build upon a data set of approximately 20 years of daily close prices set, from January 1987 to June 2007, from a comprehensive sample of leading aerospace-related companies with stocks negotiated on the New York Exchange (NYSE) and on the over-the-counter (OTC) markets. We also introduced the sub-indices CASI-AERO, for aeronautical segment, and CASI-SAT, for satellite segment, and considered the relation between them. These three indices are compared to others aerospace indices and to more traditional general financial indices like DJIA, S&P500 and Nasdaq. Our results have shown that the CASI is an index that describes very well the aerospace sector behavior, since it is able to reflect the aeronautical segment comportment as well as the satellite one. Therefore, in this sense, it can be considered as a representative index of the aerospace sector. Moreover, the creation of two sub-indices, the CASI-AERO and the CASI-SAT, allows to elucidate capital movements within the aerospace sector, particularly those of speculative nature, like the dot.com bubble and crash of 1998–2001.  相似文献   
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Morphing wing structures are widely considered among the most promising technologies for the improvement of aerodynamic performances in large civil aircraft. The controlled adaptation of the wing shape to external operative conditions naturally enables the maximization of aircraft aerodynamic efficiency, with positive fallouts on the amount of fuel burned and pollutant emissions. The benefits brought by morphing wings at aircraft level are accompanied by the criticalities of the enabling technologies, mainly involving weight penalties, overconsumption of electrical power, and safety issues. The attempt to solve such criticalities passes through the development of novel design approaches, ensuring the consolidation of reliable structural solutions that are adequately mature for certification and in-flight operations. In this work, the development phases of a multimodal camber morphing wing flap, tailored for large civil aircraft applications, are outlined with specific reference to the activities addressed by the author in the framework of the Clean Sky program.The flap is morphed according to target shapes depending on aircraft flight conditions and defined to enhance high-lift performances during takeoff and landing, as well as wing aerodynamic efficiency during cruise. An innovative system based on finger-like robotic ribs driven by electromechanical actuators is proposed as morphing-enabling technology; the maturation process of the device is then traced from the proof of concept to the consolidation of a true-scale demonstrator for pre-flight ground validation tests. A step-by-step approach involving the design and testing of intermediate demonstrators is then carried out to show the compliance of the adaptive system with industrial standards and safety requirements. The technical issues encountered during the development of each intermediate demonstrator are critically analyzed, and justifications are provided for all the adopted engineering solutions. Finally, the layout of the true-scale demonstrator is presented, with emphasis on the architectural strengths, enabling the forthcoming validation in real operative conditions.  相似文献   
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