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This paper aims to describe a methodology to optimize the trajectory of unconventional airship performing a high-altitude docking manoeuvre.

The trajectories are based upon Bezier curves whose control points positions are optimized through particle swarm optimization algorithm. A minimum energy strategy is implemented by considering the airship physical properties. The paper describes the mathematical model of the airships, the trajectories modelling through Bezier’s curves and the optimization framework. A series of test cases has been developed to evaluate the proposed methodology.

Results obtained show that the implemented procedure is able to optimize the airship trajectories and to support their in-flight docking; a strong influence of the wind speed and course on the trajectories planning is highlighted.

The wind speed considered in these simulations depends only on altitude, and gusts effect has been neglected.

The proposed model can support the study of unconventional airship trajectories and can be useful to evaluate best in-air docking strategies.

The paper addresses the problem of trajectory optimization for a class of new air vehicles with an heuristic approach.

In this study, a finite element model of a box-girder bridge along with the railway sub-track system is developed to predict the static behavior due to different combinations of the Indian railway system and free vibration responses resulting in different natural frequencies and their corresponding mode shapes.

The modeling and evaluation of the bridge and sub-track system were performed using non-closed form finite element method (FEM)-based ANSYS software.

From the analysis, the worst possible cases of deformation and stress due to different static load combinations were determined in the static analysis, while different natural frequencies were determined in the free vibrational analysis that can be used for further analysis because of the dynamic effect of the train vehicle.

The scope of the current investigation is confined to the structure's static and free vibration analysis. However, this study will help the designers obtain relevant information for further analysis of the dynamic behavior of the bridge model.

In static analysis, the maximum deformation of the bridge deck was found to be 10.70E-03m due to load combination 5, whereas the maximum natural frequency for free vibration analysis is found to be 4.7626 Hz.