In this study, the free vibration analysis of rotating and non-rotating fiber metal laminate (FML) beams, hybrid composite beams (HCB), and functionally graded beams (FGB) are investigated. FML beams are high-performance hybrid structures based on alternating stacked arrangements of fiber-reinforced plastic (FRP) plies and metal alloy layers. Hybrid composite beams are materials that are made by adding two different fibers. Functionally graded beams are new materials that are designed to achieve a functional performance with gradually variable properties in one or more directions. The effects of different metal alloys, composite fibers, and different aspect ratios and angular velocities on the free vibration analysis of FML beams are studied. The effects of different angular velocities and different aspect ratios of rotating and non-rotating hybrid composite beams are also investigated. Finally, the effects of different angular velocities and different material distributions, namely the power law, exponential distribution, and Mori Tanaka's scheme on the free vibration analysis of FGB, are also invesigated.

This paper deals with finding the optimum parameters of a damped dynamic vibration absorber (DVA) to control chatter in metal cutting systems. The performance of conventional damped DVA is compared with the proposed skyhook damper in which the damper of the absorber system is connected between the absorber mass and an inertial reference in the sky, referred to as a skyhook damper. The damped DVA is optimized by reducing the magnitude in the positive side and increasing it in the negative side of the real part of the frequency response function of the main system. The optimum frequency ratio and the damping ratio of the damped DVA for the undamped and damped main system are obtained using analytical solutions and a numerical optimisation technique, viz genetic algorithm, respectively. The performance of the proposed skyhook damper is marginally better than the conventional type of damped DVA in controlling the vibration of the main system. This is verified by analyzing both the proposed and conventional models using finite element method-based commercial software ANSYS.

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UltraWide Bandwidth (UWB) antenna with Deflected Ground Structure for wireless communication is presented in this paper. Our proposed antenna design is consisting of elliptical shape slot at patch and Quarter wave transmission line at the ground with multiband frequency operation in various wireless communications.An antenna is designed using FR4 substrate with permittivity value of 4.4 and thickness of 0.8 mm. The size of the antenna is 50 x 70 mm2presents a high gain of 4 dB with Ultra Wide Bandwidth. In proposed antenna quarter wave ground is imposed with Deflected Ground Structure to achieve overall size reduction. The ultra bandwidth antenna proposed in this paper operates at multiband frequencies centered at 3.0267 GHz, 6.1933 GHz, 9.1911 GHz, 12.1467 GHz, and 15.06 GHz with corresponding return loss of -24.0553 dB, -40.9292 dB, -20.7534 dB, -41.8718 dB, -30.1747 dB.