Ji Hoon Lee

A nonlinear command and stability augmentation system is designed based on feedback linearization for a morphing aircraft in the presence of different variable-span configurations. A variable-span morphing aircraft model is obtained by modifying a conventional aircraft model. Feed-forward neural networks are trained to learn the inverse dynamics in various morphing configurations and flight conditions. An attitude orientation system is designed to stabilize the airframe and track the commanded a

A highly efficient phase-transfer catalytic aza-Michael addition of tert-butyl benzyloxycarbamate to a wide range of electron-deficient olefins is presented (90-99%).

We prove sharp interpolatory estimates between directional Haar projections and Riesz Transforms. We apply those to prove a conjecture of L. Tartar that arose within the theory of compensated compactness. To provide a frame of reference for the analytical estimates addressed in this paper we briefly review the core ideas of compensated compactness as developed by Murat and Tartar.

In this study a multi-level path planning system is proposed for indoor search and rescue operations. Requirements for the path planning system are derived based on the operational concept of the integrated indoor navigation system. Different aspects of various path planning algorithms are assessed, and their suitability to search and rescue operations in structured indoor environments is investigated. A five-step path planning system is proposed, which consists of map pre-processing, segment pa

Preserving the sharpness of edge structures is highly challenging to image interpolation. In this paper, we propose an edge-oriented two-step interpolation method that utilizes an edge training set. For edge interpolation, the LR edge map is converted into the HR edge map by using the training set. Then, an image is classified into smooth and edge regions using the HR edge map, and both regions are interpolated separately. For edge regions, adaptive edgeoriented interpolation is performed by usi

In this study, a sliding mode controller is designed for a longitudinal dynamic model of a span and sweep-varying morphing unmanned aerial vehicle. Changes in aerodynamic and dynamic characteristics of the morphing wing aircraft model are investigated. Controller is designed based on an input-output linearization scheme to accomplish regulation and command tracking of airspeed and altitude. Numerical simulation is performed, and the results show that nominal tracking performance of the proposed

<p style='text-indent:20px;'>In this paper, we prove the continuity of global attractors and the Gromov-Hausdorff stability of reaction diffusion equations with Robin boundary conditions under perturbations of the domain and equation if every equilibrium of the unperturbed equation is hyperbolic.

In this study, a novel framework for the flight control of a morphing unmanned aerial vehicle (UAV) based on linear parameter-varying (LPV) methods is proposed. A high-fidelity nonlinear model and LPV model of an asymmetric variable-span morphing UAV were obtained using the NASA generic transport model. The left and right wing span variation ratios were decomposed into symmetric and asymmetric morphing parameters, which were then used as the scheduling parameter and the control input, respective