5,022 research outputs found

    Flutter Prediction for Aircraft Conceptual Design

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    Flutter prediction is usually a knowledge-based analysis process that aims to reduce the cost of aeroelastic stability margin certification. However, early detection of flutter problems is beneficial in the development of unconventional aircraft. The recently developed automation tool ConceptFEA for structural sizing of aircraft concepts paves the way for rapid physics-based flutter prediction of aircraft concepts. A match-point iteration procedure using the p-k method is implemented for ConceptFEA with minimum user input requirements to generate flutter boundary points. A subsonic business jet concept and its high aspect-ratio wing variant are used to demonstrate how the newly developed flutter prediction capability can be used during aircraft conceptual design. Sized structures, flutter boundary curves, and flutter sensitivity analysis results are generated for these two concepts using ConceptFEA. The relevant equivalent plate theory is provided to show the quantitative relationships between a stiffened panel and its equivalent NASTRAN PSHELL panel. The rapid flutter prediction capability of ConceptFEA makes multidisciplinary collaborations between systems analysts and aeroelasticity experts feasible in practice

    On the modeling of neural cognition for social network applications

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    In this paper, we study neural cognition in social network. A stochastic model is introduced and shown to incorporate two well-known models in Pavlovian conditioning and social networks as special case, namely Rescorla-Wagner model and Friedkin-Johnsen model. The interpretation and comparison of these model are discussed. We consider two cases when the disturbance is independent identical distributed for all time and when the distribution of the random variable evolves according to a markov chain. We show that the systems for both cases are mean square stable and the expectation of the states converges to consensus.Comment: submitted to IEEE CCAT 201
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