2 research outputs found

    Multidisciplinary design optimization of wing shape with nacelle and pylon

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    A Multidisciplinary Design Optimization (MDO) system for a wing with nacelle and pylon is developed. The present MDO system is based on the integration of Computational Fluid Dynamics (CFD) codes and NASTRAN based an aeroelastic-structural interface code. The Kriging model is employed to save the computational time of objective function evaluations in Multi-Objective Genetic Algorithm (MOGA). In the present multi-objective optimization, aerodynamic optimization is performed to minimize the drag and the shock wave strength at inboard of pylon, and structural optimization is performed to obtain the minimum wing weight with the constraints of flutter and strength. As a result of the optimization, several solutions improved in all objective function values compared with the baseline shape have been obtained. Furthermore, features of the design space have been investigated by data mining techniques using Self-Organizing Map (SOM) and ANalysis Of VAriance (ANOVA)

    Longitudinal and transverse exciton-spin relaxation in a single InAsP quantum dot embedded inside a standing InP nanowire using photoluminescence spectroscopy

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    We have investigated the optical properties of a single InAsP quantum dot embedded in a standing InP nanowire. Elongation of the transverse exciton-spin relaxation time of the exciton state with decreasing excitation power was observed by first-order photon correlation measurements. This behavior is well explained by the motional narrowing mechanism induced by Gaussian fluctuations of environmental charges in the nanowire. The longitudinal exciton-spin relaxation time is evaluated by the degree of the random polarization of emission originating from exciton states confined in a single-nanowire quantum dot by using Mueller calculus based on Stokes parameters representation. The reduction in the random polarization component with decreasing excitation power is caused by suppression of the exchange interaction of electron and hole due to an optically induced internal electric field by the dipoles at the wurtzite and zinc-blende heterointerfaces in the InP nanowireQN/Quantum NanoscienceApplied Science
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